Drive unit with its drive transmission system and connected operating heat cycles and functional configurations

Abstract

The invention relates to a heat engine (29), including a drive unit (1) provided with: a casing (2) delimiting therein an annular chamber (12), two triads of pistons (7a-7b-7c; 9a-9b-9c) rotatably housed in the casing of the annular cylinder (or toroidal cylinder), a three-shaft movement system (18) configured to transmit motion from and/or to the two triads of pistons; wherein the heat engine is configured so as to carry out a Rankine or Rankine-Hirn thermodynamic cycle, capable of producing electrical energy and heat; the same invention further relates to a pneumatic motor (61) including the aforesaid drive unit (1), configured so as to transform the compressed air at high pressure, contained in a tank, into mechanical energy.

Claims

1. A heat engine (29), configured so as to carry out a Rankine-Hirn heat cycle, comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of a thermal fluid in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a steam generator (30) disposed upstream of the drive unit (1) and in fluid communication, via the conduit (34), with a first inlet opening (15) of the drive unit (1), so as to supply a flow of saturated steam able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and to produce a first part of useful work; a steam superheater (36), interposed between a first discharge opening (16) of the drive unit (1) and second and third inlet openings (15, 15) thereof, in fluid communication, via the conduits (35, 36, 34, 34), so as to supply a flow of superheated steam able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and to produce a second part of useful work; an electric generator (G) connected to the primary shaft (17) of the drive unit (1), so as to receive mechanical energy and produce electrical energy; a condenser (31) disposed downstream of the drive unit (1) and in fluid communication, via the conduits (35, 35, 35), with a second and a third discharge opening (16, 16) of the drive unit (1), so as to receive a flow of spent steam and extract heat therefrom; a pump (32) in fluid communication, via the conduits (32, 32) with the steam generator (30).

2. A heat engine (29), configured so as to carry out a Rankine-Hirn heat cycle, comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of a thermal fluid in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a steam generator (30) disposed upstream of the drive unit (1) and in fluid communication, via the conduits (33, 34, 34), with first two inlet openings (15, 15) of the drive unit (1), so as to supply a flow of superheated steam able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and produce a first part of useful work; a steam superheater (36), interposed between first two discharge openings (16, 16) of the drive unit (1) and a third inlet opening (15) of thereof, in fluid communication, via the conduits (35, 35, 36, 34), so as to supply a flow of superheated steam able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and produce a second part of useful work; an electric generator (G) connected to the primary shaft (17) of the drive unit (1), so as to receive mechanical energy and produce electrical energy; a condenser (31) disposed downstream of the drive unit (1) and in fluid communication, via the conduit (35), with the discharge opening (16) of the drive unit (1), so as to receive a flow of spent steam and extract heat therefrom; a pump (32) in fluid communication, via the conduits (32, 32) with the steam generator (30).

3. A heat engine (29), configured so as to carry out a Rankine-Hirn heat cycle, comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of a thermal fluid in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a steam generator (30) disposed upstream of the drive unit (1) and in fluid communication, via the conduit (34), with a first inlet opening (15) of the drive unit (1), so as to supply a flow of saturated steam able to contribute to rotation of the rotors (4, 5) of the drive unit (1) and produce a first part of useful work; a first steam superheater (36), interposed between a first discharge opening (16) of the drive unit (1) and a second inlet opening (15) thereof, in fluid communication, via the conduits (35, 34), so as to supply a superheated flow of steam able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and produce a second part of useful work; a second steam superheater (37), interposed between a second discharge opening (16) of the drive unit (1) and a third inlet opening (15) thereof, in fluid communication, via the conduits (35, 34), so as to supply a superheated steam flow able to contribute to the rotation of the rotors (4, 5) of the drive unit (1) and produce a third part of useful work; an electric generator (G) connected to the primary shaft (17) of the drive unit (1), so as to receive mechanical energy and produce electrical energy; a condenser (31) disposed downstream of the drive unit (1) and in fluid communication, via the conduit (35), with a third discharge opening (16) of the drive unit (1), so as to receive a flow of spent steam and extract heat therefrom; a pump (32) in fluid communication, via the conduits (32, 32), with the steam generator (30).

4. A heat engine (29), configured so as to carry out a Rankine-Hirn heat cycle, comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of a thermal fluid in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a steam generator (30) disposed upstream of the drive unit (1) and in fluid communication, via the conduits (33, 34, 34, 34), with the inlet openings (15, 15, 15) of the drive unit (1), in order to supply thereto a flow of saturated steam able to rotate the rotors (4, 5) of the drive unit (1) and produce useful work; an electric generator (G) connected to the primary shaft (17) of the drive unit (1), so as to receive mechanical energy and produce electrical energy; a condenser (31) disposed downstream of the drive unit (1) and in fluid communication, via the conduits (35, 35, 35, 35), with the discharge openings (16, 16, 16) of the drive unit (1), so as to receive a flow of spent steam and extract heat therefrom; a pump (32) in fluid communication, via the conduits (32, 32), with the steam generator (30); wherein the heat engine (29) is equipped with a heating apparatus (300) comprising: a first superheater (71) interposed between the steam generator and an inlet opening (15) of the drive unit (1), by means of which superheated steam flows into a first expansion chamber of the drive unit (1); and/or a second superheater (72) interposed between a discharge opening (16) of the drive unit (1), from which steam is discharged at the end of expansion in the first chamber, and an inlet opening (15) of the drive unit (1), the second superheater being configured so as to receive spent steam expelled by the first expansion chamber and superheat it in such a way that the superheated steam flows, via the inlet opening (15), into the second expansion chamber of the drive unit (1); and/or a third superheater (73) interposed between a discharge opening (16) of the drive unit (1), from which steam is discharged at the end of expansion in a second chamber, and the inlet opening (15) of the drive unit (1), the second superheater being configured so as to receive the spent steam expelled by the second expansion chamber and superheat it, in such a way that the superheated steam flows, via the inlet opening (15) into a third expansion chamber of the drive unit (1); wherein the heat engine (29) comprises a regenerator (80), interposed between a discharge opening (16) of the drive unit (1), from which the spent steam is discharged at the end of expansion in the third expansion chamber, and the condenser (31), where the steam is condensed and transformed into a flow of water, thus recovering heat, the regenerator (80) being configured so as to receive the steam expelled from the drive unit (1) at the end of expansion in the third expansion chamber and exchange the residual heat of the steam with the flow of water downstream of the condenser (31), pumped under high pressure by the pump (32) back toward the steam generator (30) so as to lend continuity to the closed-circuit cycle; wherein the heating apparatus (300) comprises, operatively downstream of the first superheater, the second superheater and the third superheater (71, 72, 73), a fume temperature reducer (75), the reducer (75) being configured so as to extract heat from fumes produced by the heating apparatus and being interposed between the discharge opening (16) of the drive unit (1), from which the spent steam is discharged at the end of expansion in the third expansion chamber, and the regenerator (80), in which the steam exchanges its residual heat with the flow of condensed water directed toward the steam generator (30), the fume temperature reducer (75) being configured so as to receive, on an inlet side, the spent steam output by the drive unit (1), in order to exchange heat with the fumes of the heating apparatus (300), thereby raising the temperature of the steam, and deliver, from an outlet side, the heated steam directed to the regenerator (80).

5. A heat engine (51), comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of a thermal fluid in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a cooler (43), in fluid communication, via a conduit (46), with a regenerator (42), and able to cool the thermal fluid in circulation, with or without heat recovery; a first section of the drive unit (1) in fluid communication with the cooler (43), via the conduit (43), where, following the movement away of two pistons (9c, 7c), the thermal fluid, passing through an inlet opening (15), is drawn into a chamber (13); a second section of the drive unit (1), where, following the nearing movement of the two pistons (7c, 9a), the thermal fluid previously taken in is compressed in a chamber (14) and then, on passing through a discharge opening (16), a conduit (44) and a check valve (44a), is conveyed into a compensating tank (44); the compensating tank (44), configured so as to accumulate the compressed thermal fluid in order to make it always and immediately available, via the conduits (44, 42) and a check valve (44b), for subsequent use thereof, in a continuous mode; a preheating serpentine (42a), in fluid communication, via the conduit (42) with a heating serpentine (41a), and having the purpose of preheating the thermal fluid in a pathway thereof towards a heater (41); the heater (41), configured so as to be able to superheat the thermal fluid circulating in the heating serpentine (41a) by using heat energy produced by a burner (40); the burner (40), capable of supplying heat energy to the heater (41); a third section of the drive unit (1), in fluid communication with the heating serpentine (41a), via conduits (41, 41, 41), and able to receive, via inlet openings (15, 15), the thermal fluid heated up to a high temperature under pressure in the heating serpentine (41a) in order then to expand the fluid in the chambers (13, 13), delimited respectively by the pistons (9a, 7a, 9b, 7b), in order to rotate the pistons in the direction of the arrows and produce useful work; a fourth section of the drive unit (1), in fluid communication with the regenerator (42), through the discharge openings (16, 16) and conduits (45, 45, 46), and in which, due to the reduction in volume of the two chambers (14, 14) determined by the nearing of the two pairs of pistons (7a, 9b, 7b, 9c), the spent thermal fluid is forcedly expelled towards the regenerator (42); the regenerator (42), in fluid communication with the drive unit (1), configured so as to acquire heat energy from the spent thermal fluid and use it to preheat, via the preheating serpentine (42a), the thermal fluid to be sent to the heating serpentine (41a).

6. The heat engine (51), according to claim 5, where the conduits (41, 41) for the thermal fluid and the conduits (45, 45) are provided with appropriate shut-off/regulating valves, manually or automatically controlled, in order to be able to intercept the heat flow of one or the other inlet opening (15, 15) and the corresponding discharge openings (16, 16) of the drive unit (1), or to divert the flow to one or the other of the two.

7. A heat engine (51), comprising: a drive unit (1) provided with a casing (2) delimiting therein an annular chamber (12) and having two inlet openings (15, 15) and two discharge openings (16, 16), the drive unit comprising a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has two pistons (7a, 7b; 9a, 9b) slidable in the annular chamber; a cooler (43), in fluid communication, via a conduit (46), with a regenerator (42), and able to cool thermal fluid in circulation, with or without heat recovery; a first section of the drive unit (1) in fluid communication with the cooler (43), via a conduit (43), where, following a movement away movement of the two pistons (9c, 7c) the thermal fluid, passing through an inlet opening (15), is drawn into a chamber (13); a second section of the drive unit (1), where, following the nearing movement of the two pistons (7b, 9a), the thermal fluid previously taken in is compressed in a chamber (14) and then, on passing through a first discharge opening (16), a conduit (44) and a check valve (44a), is conveyed into a compensating tank (44); the compensating tank (44), configured so as to accumulate compressed thermal fluid in order to make it always and immediately available, via conduits (44, 42) and a check valve (44b), for subsequent use thereof, in a continuous mode; a preheating serpentine (42a), in fluid communication, via a conduit (42), with a heating serpentine (41a), and having the purpose of preheating the thermal fluid in a pathway thereof towards a heater (41); the heater (41), configured so as to be able to superheat the thermal fluid circulating in the heating serpentine (41a) by using heat energy produced by a burner (40); the burner (40), capable of supplying heat energy to the heater (41); a third section of the drive unit (1), in fluid communication with the heating serpentine (41a), via a conduit (41), and able to receive, via a second inlet opening (15), the thermal fluid heated up to a high temperature under pressure in the heating serpentine (41a) in order then to expand the fluid in a chamber (13), delimited by the pistons (9a, 7a), in order to rotate the pistons and produce useful work; a fourth section of the drive unit (1), in fluid communication with the regenerator (42), through a second discharge opening (16) and a conduit (46), and in which, due to the reduction in volume of the chamber (14) determined by the nearing of the two pistons (7a, 7b), spent thermal fluid is forcedly expelled towards the regenerator (42); the regenerator (42), in fluid communication with the drive unit (1), configured so as to acquire heat energy from the spent thermal fluid and use it to preheat, via the preheating serpentine (42a), the thermal fluid to be sent to a heating serpentine (41a).

8. A pneumatic motor, comprising: a drive unit (1) comprising: a casing (2) delimiting therein an annular chamber (12) and having inlet or discharge openings (15, 16, 15, 16, 15, 16) in fluid communication with conduits external to the annular chamber (12), in which each inlet or discharge opening (15, 16, 15, 16, 15, 16) is angularly spaced from adjacent inlet or discharge openings in order to define an expansion/compression pathway of compressed air in the annular chamber (12); a first rotor (4) and a second rotor (5) rotatably installed in the casing (2); wherein each of the two rotors (4, 5) has three pistons (7a, 7b, 7c; 9a, 9b, 9c) slidable in the annular chamber (12); wherein the pistons (7a, 7b, 7c) of one rotor (4) of the rotors (4, 5) are angularly alternated with the pistons (9a, 9b, 9c) of the other rotor (5); wherein angularly adjacent pistons (7a, 9a; 7b, 9b; 7c, 9c) delimit six variable-volume chambers (13, 13, 13; 14, 14, 14); a primary shaft (17) operatively connected to the first and second rotors (4, 5); a transmission (18) operatively interposed between the first and second rotors (4, 5) and the primary shaft (17) and configured so as to transform the rotary motion having a constant angular velocity of the primary shaft (17) into a rotary motion with respective first and second periodically variable angular velocities (?1, ?2) of the first and second rotors (4, 5) that are offset relative to each another; wherein the transmission (18) is configured so as to confer on the periodically variable angular velocity (?1, ?2) of each of the rotors (4, 5) six periods of variation for each complete revolution of the primary shaft (17), and wherein the drive unit (1) is used as a rotary volumetric expander; a compressed air tank (46) in direct fluid communication, via conduits (46, 46) and a manual or automatic shut-off/regulating valve (46a), with the drive unit (1) in order to supply high-pressure compressed air to the drive unit; a first section of the drive unit (1) which, via a first inlet opening (15), receives compressed air at a high pressure, which, because of the expansion thereof in a first chamber (13), delimited by the pistons (9a, 7a), rotates the latter producing a first part of work; a first heater (47) in direct fluid communication, via a conduit (47), with a first discharge opening (16) of the drive unit (1) in order to receive therethrough the compressed air which, as a result of the nearing of the two pistons (7a, 9b), is discharged from an expansion chamber (14) so as to be heated in the first heater (47) and then reintroduced into the drive unit (1) through a conduit (47) and the second inlet opening (15); a second section of the drive unit (1) which, through a second inlet opening (15), receives compressed air at medium pressure, which, because of the expansion thereof in a second chamber (13), delimited by pistons (9b, 7b), rotates the pistons (9b, 7b) in a direction of motion, producing a second part of work; a second heater (48) in direct fluid communication, via a conduit (48), with a second discharge opening (16) of the drive unit (1) in order to receive therethrough the compressed air which, as a result of the nearing of two pistons (7b, 9c), is discharged from the expansion chamber (14) so as to be heated in the second heater (48) and then reintroduced into the drive unit (1) through a conduit (48) and a third inlet opening (15); a third section of the drive unit (1) which, through the third inlet opening (15), receives compressed air at low pressure, which, because of the expansion thereof in a third chamber (13), delimited by pistons (9c, 7c), rotates the pistons (9c, 7c) in the direction of motion, producing a third part of work; a conduit (49) in communication with the third discharge opening (16) of the drive unit (1) in order to receive therethrough the compressed air which, as a result of the nearing of the two pistons (7c, 9a), is discharged from the expansion chamber (14) in order to be then discharged into a surrounding environment.

9. The pneumatic motor according to claim 8, comprising: a third heater (49) in direct fluid communication, via the conduit (49), with the third discharge opening (16) of the drive unit (1) in order to receive therethrough the compressed air, which, as a result of the nearing of the two pistons (7c, 9a), is discharged from the expansion chamber (14) so as to be heated in the third heater (49) and then reintroduced into an additional drive unit arranged in cascade with the drive unit (1).

Description

DESCRIPTION OF THE DRAWINGS

(1) The description will be set forth here below with reference to the appended drawings, provided only for illustrative purposes and thus non-limiting, in which:

(2) FIG. 1 shows a schematic front view of a drive unit according to the present invention;

(3) FIG. 2a illustrates a side sectional view of the central body of the drive unit in FIG. 1;

(4) FIG. 2b is a side sectional view of a variant of the central body of the drive unit in FIG. 1, with a section of the motion transmission system;

(5) FIG. 3 illustrates a front view of the train of three-lobe gears belonging to the motion transmission system;

(6) FIG. 4 illustrates a first diagram of a heat engine comprising the drive unit according to the present invention;

(7) FIG. 5 illustrates a second diagram of a heat engine comprising the drive unit according to the present invention;

(8) FIG. 6 illustrates a third diagram of a heat engine comprising the drive unit according to the present invention;

(9) FIG. 7 illustrates a fourth diagram of a heat engine comprising the drive unit according to the present invention;

(10) FIG. 8 illustrates a fifth diagram of a heat engine comprising the drive unit according to the present invention;

(11) FIG. 9 represents the pressure-volume diagram of a generic Stirling thermal cycle;

(12) FIG. 10 illustrates a diagram of a six-piston heat engine using the drive unit with the new pulsating heat cycle according to the present inventive idea;

(13) FIG. 11 illustrates a diagram of a four-piston heat engine using the new pulsating heat cycle according to the present inventive idea;

(14) FIG. 12 illustrates a diagram of a six-piston drive unit used as a pneumatic motor;

(15) FIG. 13 illustrates a further possible diagram of a heat engine comprising the drive unit according to the present invention;

(16) FIG. 14 illustrates a further possible diagram of a heat engine comprising the drive unit according to the present invention.

DETAILED DESCRIPTION OF THE DRIVE UNIT

(17) With reference to FIGS. 1, 2a, 2b, 1 denotes overall a drive unit, the main subject matter of the present inventive idea, used as an expander in closed-circuit heat cycles of the Rankine type operating with organic fluids, as an expander in closed-circuit heat cycles of the Rankine and Rankine-Hirn type, operating with steam, as a compressor/expander in open-circuit heat cycles of the Brayton type operating with hot air, as a compressor/expander in closed-circuit heat cycles of the Stirling type operating with hot air (in reality nitrogen, helium, hydrogen, etc.), or else directly utilizable as a hydraulic motor, pneumatic motor, pneumatic compressor, volumetric pump and in many other applications that can exploit the particular motor features thereof.

(18) The drive unit 1 comprises a casing 2 which internally delimits a seat 3.

(19) In the non-limiting embodiment illustrated, the casing 2 is formed by two half-parts 2a, 2b joined together.

(20) Housed in the seat 3 there is a first rotor 4 and a second rotor 5, which rotate around a same axis X-X.

(21) The first rotor 4 has a first cylindrical body 6 and three first elements 7a, 7b, 7c which extend radially from the first cylindrical body 6 and are rigidly connected or integral therewith.

(22) The second rotor 5 has a second cylindrical body 8 and three second elements 9a, 9b, 9c which extend radially from the second cylindrical body 8 and are rigidly connected or integral therewith.

(23) The elements 7a, 7b, 7c of the rotor 4 are angularly equidistant from one another, i.e. each element is spaced apart from the adjacent element by an angle ? of 120? (measured between the planes of symmetry of each element).

(24) The elements 9a, 9b, 9c of the rotor 5 are angularly equidistant from one another, i.e. each element is spaced apart from the adjacent element by an angle ? of 120? (measured between the planes of symmetry of each element).

(25) The first and second cylindrical bodies 6, 8 are set side by side on respective bases 10, 11 and are coaxial.

(26) The three first elements 7a, 7b, 7c of the first rotor 4 moreover extend along an axial direction and have a projecting portion disposed in a position that is radially external to the second cylindrical body 8 of the second rotor 5.

(27) The three second elements 9a, 9b, 9c of the second rotor 5 moreover extend along an axial direction and have a projecting portion disposed in a position that is radially external to the first cylindrical body 6 of the first rotor 4.

(28) The three first elements 7a, 7b, 7c are alternated with the three second elements 9a, 9b, 9c along the circumferential extension of the annular chamber 12.

(29) Each of the first and second elements 7a, 7b, 7c, 9a, 9b, 9c has, in a radial section (FIG. 1), a substantially trapezoidal profile which converges toward the rotation axis X-X and, in a axial section (FIG. 2a,2b), a substantially circular or rectangular profile.

(30) Each of the first and second elements 7a, 7b, 7c, 9a, 9b, 9c has an angular size, given purely by way of approximation and not by way of limitation, of about 38?.

(31) Peripheral surfaces that are radially external to the first and second cylindrical bodies 6, 8 delimit, together with an inner surface of the seat 3, an annular chamber 12.

(32) The annular chamber 12 is therefore divided into variable-volume rotating chambers 13, 13, 13, 14, 14, 14 by the first and second elements 7a, 7b, 7c, 9a, 9b, 9c. In particular, each variable-volume rotating chamber is delimited (besides by the surface radially internal to the casing 2 and the surface radially external to the cylindrical bodies 6, 8) by one of the first elements 7a, 7b, 7c and one of the second elements 9a, 9b, 9c.

(33) In the first FIG. 2a, each of the first and second elements 7a, 7b, 7c, 9a, 9b, 9c has, in an axial section thereof, a substantially circular profile and the annular chamber 12 likewise has a circular cross section defined as toroidal.

(34) In the variant in FIG. 2b, each of the first and second elements 7a, 7b, 7c, 9a, 9b, 9c has, in a axial section thereof, a rectangular (or square) profile and the annular chamber 12 likewise has a rectangular (or square) cross section.

(35) Between inner walls of the annular chamber 12 and each of the aforesaid first and second elements 7a, 7b, 7c, 9a, 9b, 9c there remains a gap such as to permit the rotational movement of the pistons 4, 5 and sliding of the elements 7a, 7b, 7c, 9a, 9b, 9c in the chamber 12 itself.

(36) The first and second elements 7a, 7b, 7c, 9a, 9b, 9c are the pistons of the drive unit 1 illustrated and the variable-volume rotating chambers 13, 13, 13, 14, 14, 14 are the chambers for the compression and/or expansion of the working fluid of the aforesaid drive unit 1.

(37) The inlet or discharge openings 15, 16, 15, 16, 15, 16 (of suitable size and shape) are fashioned in a wall radially external to the casing 2; they open into the annular chamber 12 and are in fluid communication with conduits external to the annular chamber 12, illustrated further below.

(38) Each inlet or discharge opening 15, 16, 15, 16, 15, 16 is angularly spaced in an appropriate way so as to adapt to the requirements of each different individual functional configuration of the drive unit 1.

(39) The drive unit 1 further comprises a primary shaft 17 parallel to and distanced from the rotation axis X-X and rotatably mounted on the casing 2 and a transmission 18 mechanically interposed between the primary shaft 17 and the rotors 4, 5.

(40) The transmission 18 comprises a first auxiliary shaft 19 onto which the first rotor 4 is keyed and a second auxiliary shaft 20 onto which the second rotor 5 is keyed. The first and second auxiliary shafts 19, 20 are coaxial with the rotation axis X-X. The second auxiliary shaft 20 is tubular and houses within it a portion of the first auxiliary shaft 19. The first auxiliary shaft 19 can rotate in the second auxiliary shaft 20 and the second auxiliary shaft 20 can rotate in the casing 2.

(41) A first three-lobe gear 23 is keyed onto the primary shaft 17. A second three-lobe gear 24 is keyed onto the primary shaft 17 next to the first. The second three-lobe gear 24 is mounted on the primary shaft 17 angularly offset relative to the first three-lobe gear 23 by an angle ? of 60?. The two three-lobe gears 23 and 24 rotate together jointly with the primary shaft 17.

(42) A third three-lobe gear 25 is keyed onto the first auxiliary shaft 19 (so as to rotate integrally therewith) and the teeth thereof precisely enmesh with the teeth of the first three-lobe gear 23.

(43) A fourth three-lobe gear 26 is keyed onto the second auxiliary shaft 20 (so as to rotate integrally therewith) and the teeth thereof precisely enmesh with the teeth of the second three-lobe gear 24.

(44) Each of the above-mentioned three-lobe gears 23, 24, 25, 26 has approximately the profile of an equilateral triangle with rounded vertices 27 and connecting portions 28, interposed between the vertices 27, which can be concave, flat or convex.

(45) Changing the shape of the vertices 27 and connecting portions 28 of the gears makes it possible to pre-establish the value of the angular periodic movement of the auxiliary shafts 19, 20 during their rotary motion.

(46) The structure of the transmission 18 is such that during a complete revolution of the primary shaft 17 the two rotors 4, 5 also carry out a complete revolution, but with periodically variable angular velocities, offset from each other, which induce the adjacent pistons 7a, 9a; 7b, 9b; 7c, 9c to move away and toward one another three times during a complete 360? revolution. Therefore, each of the six variable-volume chambers 13, 13, 13, 14, 14, 14 expands three times and contracts three times at each complete revolution of the primary shaft 17.

(47) In others words, pairs of adjacent pistons of the six pistons 7a, 7b, 7c; 9a, 9b, 9c are movable, during their rotation at a periodically variable angular velocity in the annular chamber 12, between a first position, in which the two faces of the adjacent pistons lie substantially next to each other, and a second position, in which the same faces are angularly spaced apart by the maximum allowed. Purely by way of example, in the first position the two faces of the adjacent pistons are angularly spaced apart by about 1?, whereas in the second position the two same faces are angularly spaced apart by about 81?.

(48) The six variable-volume chambers 13, 13, 13, 14, 14, 14 are made up of a first group of three chambers 13, 13, 13 and a second group of three chambers 14, 14, 14. When the three chambers 13, 13, 13 of the first group have the minimum volume (pistons next to each other at the minimum reciprocal distance) the other three chambers 14, 14, 14 (of the second group) have the maximum volume (pistons at the maximum reciprocal distance).

(49) Detailed Description of a First Application of the Drive Unit 1.

(50) With reference to FIGS. 1 and 4, the heat engine 29 is configured so as to function with a Rankine heat cycle, which uses deionized, dimineralized and degassed water as the thermal fluid, but could also use any other fluid suited to the purpose.

(51) This solution has the following particularities: the generator 30 transforms the water into saturated steam (at the pre-established pressure/temperature); the steam, travelling through the conveying conduits 33, 34, 34, 34 and passing through the three inlet openings 15, 15, 15, flows into in the drive unit 1 (or volumetric expander) and enters the three corresponding expansion chambers 13, 13, 13; in the expansion chambers 13, 13, 13, the steam can expand, causing the pistons to rotate and producing useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a low pressure/temperature) through the three discharge openings 16, 16, 16 and the associated conveying conduits 35, 35, 35, 35 and conveyed toward the condenser 31, where it is condensed and transformed into water (recovering heat that is useful for any purpose); the condensate water travels in the conveying conduit 32 and, via the pump 32 and after passing through the conduit 32, it is pumped (at a high pressure) back into the generator 30, thus assuring the continuity of the closed-circuit cycle.

(52) In this configuration there is a perfect thermodynamic and kinematic balancing of all moving parts, so that the volumetric expander can also operate at a very high speed, without vibrations or noise.

(53) Detailed Description of a Second Application of the Drive Unit 1.

(54) With reference to FIGS. 1 and 5, the heat engine 29 is configured so as to function with a Rankine-Him heat cycle, which uses deionized, dimineralized and degassed water as the thermal fluid, but could also use any other fluid suited to the purpose.

(55) This solution has the following particularities: the generator 30 transforms the water into saturated steam (at the pre-established pressure/temperature); the steam flows via the conveying conduit 33 into the superheater 36 and while travelling therethrough undergoes superheating (at a constant pressure) and then, via suitable conveying conduits 36, 34, 34, 34 and on passing through the three inlet openings 15, 15, 15, it flows into the drive unit 1 (or volumetric expander) and enters the three corresponding expansion chambers 13, 13, 13; in the expansion chambers 13, 13, 13, the steam can expand, causing the pistons to rotate and producing useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a low pressure/temperature) through the three discharge openings 16, 16, 16 and the associated conveying conduits 35, 35, 35, 35 and conveyed toward the condenser 31, where it is condensed and transformed into water (recovering heat that is useful for any purpose); the condensate water flows through the conveying conduit 32 and, via the pump 32 and after passing through the conduit 32, it is pumped (at a high pressure) back into the generator 30, thus assuring the continuity of the closed-circuit cycle.

(56) In this configuration there is a perfect thermodynamic and kinematic balancing of all moving parts, so that the volumetric expander can also operate at a very high speed, without vibrations or noise.

(57) Detailed Description of a Third Application of the Drive Unit 1.

(58) With reference to FIGS. 1 and 6, the heat engine 29 is configured so as to function with a Rankine-Hirn heat cycle, which uses deionized, dimineralized and degassed water as the thermal fluid.

(59) This solution has the following particularities: the generator 30 transforms the water into saturated steam (at the pre-established pressure/temperature); the steam flows via the conveying conduit 34 and passes through the inlet opening 15 into the drive unit 1 (or volumetric expander) and enters the corresponding first expansion chamber 13; in the expansion chamber 13, the steam can expand, causing the pistons to rotate and producing a part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion in the first chamber 13, the spent steam is expelled (at a medium pressure/temperature) through the discharge opening 16 and the associated conveying conduit 35 and conveyed toward the superheater 36 in which it is superheated (at a constant pressure) and then, via suitable conveying conduits 36, 34, 34 and the corresponding inlet openings 15 and 15, it enters the corresponding second and third expansion chamber 13 and 13; in the expansion chambers 13 and 13, the steam can expand, causing the pistons to rotate and producing another part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a low pressure/temperature) through the two discharge openings 16,16 and the associated conveying conduits 35, 35, 35 and conveyed toward the condenser 31, where it is condensed and transformed into water (recovering heat usable for any purpose); the condensate water travels through the conveying conduit 32 and, via the pump 32 and after passing through the conduit 32, it is pumped (at a high pressure) back into the generator 30, thus assuring the continuity of the closed-circuit cycle.
Detailed Description of a Fourth Application of the Drive Unit 1.

(60) With reference to FIGS. 1 and 7, the heat engine 29 is configured so as to function with a Rankine-Hirn heat cycle, which uses deionized, dimineralized and degassed water as the thermal fluid.

(61) This solution has the following particularities: the generator 30 transforms the water into saturated steam (at the pre-established pressure/temperature); the steam flows via the conveying conduits 33, 34, 34 and passes through the inlet openings 15,15 into the drive unit 1 (or volumetric expander) and enters the corresponding first and second expansion chambers 13,13; in the expansion chambers 13 and 13, the steam can expand, causing the pistons to rotate and producing a part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled through the discharge openings 16,16 and the associated conveying conduits 35, 35, 36 (at a medium pressure/temperature) and conveyed toward the superheater 36, in which it is superheated (at a constant pressure) and then, via the conveying conduit 34 and the corresponding inlet opening 15, conveyed into the corresponding third expansion chamber 13; in the expansion chamber 13, the steam can expand, causing the pistons to rotate and producing another part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a low pressure/temperature) through the discharge opening 16 and the associated conveying conduit 35 and conveyed toward the condenser 31, where it is condensed and transformed into water (recovering heat usable for any purpose); the condensate water travels through the conveying conduit 32 and, via the pump 32 and after passing through the conduit 32, it is pumped (at a high pressure) back into the generator 30, thus assuring the continuity of the closed-circuit cycle.
Detailed Description of a Fifth Application of the Drive Unit 1.

(62) With reference to FIGS. 1 and 8, the heat engine 29 is configured so as to function with a Rankine-Hirn heat cycle with double superheating, which uses deionized, dimineralized and degassed water as the thermal fluid.

(63) This solution has the following particularities: the generator 30 transforms the water into saturated steam (at the pre-established pressure/temperature); the steam flows via the conveying conduit 34 and passes through the inlet opening 15 into the drive unit 1 (or volumetric expander) and enters the corresponding first expansion chamber 13; in the expansion chamber 13, the steam can expand, causing the pistons to rotate and producing a part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a medium pressure/temperature) through the discharge opening 16 and the associated conveying conduit 35 and conveyed toward the superheater 36, in which it is superheated (at a constant pressure) and then, via the conveying conduit 34 and the corresponding inlet opening 15, conveyed into the corresponding second expansion chamber 13; in the expansion chamber 13, the steam can expand, causing the pistons to rotate and producing another part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a medium pressure/temperature) through the discharge opening 16 and the associated conveying conduit 35 and conveyed toward the superheater 37 in which it is superheated (at a constant pressure) and then, via the conveying conduit 34 and the corresponding inlet opening 15, conveyed into the corresponding third expansion chamber 13; in the expansion chamber 13, the steam can expand, causing the pistons to rotate and producing another part of useful work (which, in this specific case, is used by the generator G to produce electricity); at the end of expansion, the spent steam is expelled (at a low pressure/temperature) through the discharge opening 16 and the associated conveying conduit 35 and conveyed toward the condenser 31, where it is condensed and transformed into water (recovering heat usable for any purpose); the condensate water travels through the conveying conduit 32 and, via the pump 32 and after passing through the conduit 32, it is pumped (at a high pressure) back into the generator 30, thus assuring the continuity of the closed-circuit cycle.

(64) FIG. 13 illustrates a further possible layout of a heat engine according to the present invention. This layout is similar to the one shown in the diagrams of FIGS. 4-8, the difference being that the elements making up the heat engine are reconfigured in such a way as to enable the production of saturated steam and superheating of steam to be managed through a single apparatus.

(65) As shown by way of example in the diagram of FIG. 13, the heat engine 29 can be provided with a heating apparatus 300 (or burner) comprising: the aforesaid steam generator 30, disposed upstream of the drive unit and configured so as to transform the water into saturated steam to be supplied to the drive unit in order to rotate the rotors; a first superheater 71 (corresponding to the superheater 36 in FIG. 5) interposed between the steam generator and the inlet opening 15 of the drive unit, via which the superheated steam flows into the first expansion chamber of the drive unit; a second superheater 72 (corresponding to the superheater 36 in FIG. 8) interposed between the discharge opening 16 of the drive unit, from which steam is output at the end of expansion in the first chamber, and the inlet opening 15 of the drive unit; the second superheater is configured so as to receive the spent steam (at a medium pressure/temperature) expelled by the first expansion chamber and superheated (at a constant pressure), in such a way that the superheated steam flows via the inlet opening 15 into the second expansion chamber of the drive unit; a third superheater 73 (corresponding to the superheater 37 in FIG. 8) interposed between the discharge opening 16 of the drive unit, from which steam is output at the end of expansion in the second chamber, and the inlet opening 15 of the drive unit; the second superheater is configured so as to receive the spent steam (at a medium pressure/temperature) expelled by the second expansion chamber and superheated (at a constant pressure), in such a way that the superheated steam flows via the inlet opening 15 into the third expansion chamber of the drive unit.

(66) The heating apparatus 300 (or burner) is configured so as to manage both the generation of steam and the various superheating steps present in the heat engine. To this end the heating apparatus has a vertical structure, in which, from bottom to top, the steam generator 30, the first superheater 71, the second superheater 72 and the third superheater 73 are located.

(67) The heating apparatus 300 comprises suitable conveying conduits which connect the inlet and discharge openings of the drive unit to the superheaters present in the heating apparatus.

(68) The heat engine in FIG. 13 is configured so as to function with a Rankine-Hirn heat cycle with triple superheating, which uses deionized, dimineralized and degassed water as the thermal fluid.

(69) FIG. 14 illustrates a further possible layout of a heat engine according to the present invention. This layout is similar to the one shown in the diagram of FIG. 13, with the addition of a fume temperature reducer 75 and regenerator 80.

(70) In this embodiment, the heat engine comprises a regenerator 80, interposed between the discharge opening 16 of the drive unit, from which the spent steam is expelled (at a low pressure/temperature) at the end of expansion in the third chamber, and the condenser 31, where the steam is condensed and transformed into water, thus recovering heat.

(71) The regenerator 80 is configured so as to receive the steam expelled from the drive unit at the end of expansion in the third chamber, and exchange the residual heat from the steam with the flow of water downstream of the condenser 31, pumped (at a high pressure) by the pump 32 back toward the generator 30, thereby assuring the continuity of the closed-circuit cycle.

(72) According to the embodiment in FIG. 14, the heating apparatus 300 (or burner) comprises, operatively downstream of the superheaters 71, 72 and 73, a fume temperature reducer 75: this reducer is configured so as to extract heat from the fumes produced by the heating apparatus, thus recovering it. The reducer 75 is interposed between the discharge opening 16 of the drive unit, from which the spent steam is expelled (at a low pressure/temperature) at the end of expansion in the third chamber, and the regenerator 80, in which the steam exchanges its residual heat with the flow of condensate water directed back to the generator 30, where the cycle starts again. Essentially, the fume temperature reducer 75 receives as input the spent steam output by the drive unit, exchanges heat with the fumes of the burner, thereby increasing the temperature of the steam, and outputs the heated steam directed to the regenerator 80. In this manner, the steam output by the drive unit arrives at the regenerator 80 with a higher temperature, thanks to the exchange of heat that takes place in the reducer 75, where the steam recovers heat thanks to the fumes.

(73) Detailed Description of a Sixth Application of the Drive Unit 1.

(74) With reference to FIG. 10, in order to describe the functions of the new pulsating heat cycle according to the present inventive idea, it is necessary to start off by noting that in the drive unit 1, in each of the six periodically variable-volume chambers 13, 13, 13, 14, 14, 14 (each delimited by the two pistons adjacent to each other and rotating inside the annular cylinder), the diversified intake, compression, expansion and expulsion functions are performed periodically.

(75) For the sake of simplicity, in the following description, the path followed by the thermal fluid in the different sections of the heat engine 51 will be explained as if a single complete heat cycle were involved. In reality, for each revolution angle of 60? of the drive shaft (with a total revolution angle of 360?) no fewer than six complete heat cycles are carried out.

(76) Every heat cycle, in its complete form (apart from start-up), is carried out continuously in the following phases of thermodynamic variation of the fluid: intake of the cooled fluid, compression of the fluid taken in, accumulation of the compressed fluid, preheating of the compressed fluid, superheating of the compressed-preheated fluid, expansion of the superheated fluid (and corresponding production of useful work), expulsion of the spent fluid, recovery of heat energy from the spent fluid and cooling of the spent fluid (with possible recovery of heat for different uses), as described below.

(77) With reference to FIGS. 2b,10, in an application of the drive unit 1 (with six pistons), illustrated purely by way of non-limiting example, the heat engine 51 according to the present inventive idea is configured so as to operate with the new pulsating heat cycle using any thermal fluid suited to the purpose (for example: air, nitrogen, helium, hydrogen, etc).

(78) The heat engine 51 is started up in the following manner: the burner 40 is activated and, via the heater 41, heats the thermal fluid contained in the serpentine 41a up to a preset minimum temperature; when the thermal fluid contained in the serpentine 41a has reached the preset minimum temperature, the primary shaft 17 and the whole transmission system which moves the six pistons 7a, 7b, 7c, 9a, 9b, 9c are made to start rotating by a specific starter (not represented in the figure, but which could also be the same electric generator connected to the primary shaft 17 of the drive unit 1), thereby creating the preliminary condition for initiating the cycle; at this point the burner 40 is activated and, via the heater 41, heats the thermal fluid contained in the serpentine 41a up to a preset maximum temperature, thereby creating the conditions for the start-up and normal, continuous operation of the heat engine 51.

(79) With reference to FIG. 10, in the position in which the pistons are located, the following main phases can be identified:

(80) Phase of Intake of the Cooled Thermal Fluid.

(81) On leaving the cooler 43, the thermal fluid travels through the conduit 43 and after passing through the intake opening 15, is drawn into the chamber 13 as result of the movement away of the two pistons 9c-7c.

(82) Phase of Compression of the Thermal Fluid Taken in.

(83) As the two pistons 7c-9a move nearer, the thermal fluid (taken in during the previous cycle) is compressed and the temperature thereof increases.

(84) Phase of Accumulation of the Compressed Thermal Fluid.

(85) The compressed fluid, after passing through the discharge opening 16, the conduit 44 and the check valve 44a, is conveyed into the compensating tank 44, where it remains available for immediate use in the subsequent phases.

(86) Phase of Preheating of the Compressed Thermal Fluid.

(87) When, as a result of the input of the heated thermal fluid into the chambers 13-13, the pressure of the thermal fluid circulating in the serpentine 41a falls below that of the compensating tank 44, the fluid, after passing through the check valve 44b, flows through the conduit 44 and, whilst travelling through the entire serpentine 42a in the section 42-42, acquires heat energy from the regenerator 42 until arriving at the heating serpentine 41a.

(88) The heat engine 51 can comprise, in addition or as an alternative to the check valve 44b, a check valve 44c, interposed between the outlet 42 of the serpentine 42a and the inlet of the heating serpentine 41a.

(89) Phase of Superheating of the Compressed-Preheated Thermal Fluid.

(90) The burner 40 (fed with any type of fuel) supplies heat energy to the heater 41 (which, instead of the burner 40, can also use other heat sources: solar energy, residual energy from industrial processes, etc.), so that on passing through the entire serpentine 41a, the compressed-preheated thermal fluid undergoes a rapid increase in temperature and pressure.

(91) Phase of Expansion of the Superheated Thermal Fluid.

(92) When the pistons 7a-7b, rotating in the annular cylinder in the direction of motion indicated by the arrows, open the inlet openings 15-15 (thus also performing a valve function), the superheated thermal fluid, after travelling through the conduits 41-41-41, enters the expansion chambers 13 and 13, in which it can expand, causing the pistons to rotate and producing useful work (which may be used to produce electricity or for any other purpose).

(93) Phase of Expulsion of the Spent Thermal Fluid.

(94) As the pistons 7a-9b and 7b-9c move nearer, the chambers 14 and 14 are reduced in volume and the spent thermal fluid (already expanded in the previous cycle), after passing through the two discharge openings 16-16 and through the conduits 45-45-46, is expelled from the drive unit 1 toward the regenerator 42.

(95) Phase of Recovery of Heat Energy from the Spent Thermal Fluid.

(96) The spent thermal fluid expelled from the drive unit 1, while passing through the regenerator 42, transfers thereto part of the heat energy still possessed and thus undergoes a first cooling.

(97) Phase of Cooling of the Spent Fluid.

(98) The thermal fluid leaving the regenerator 42 travels through the conduit 46 and, while passing through the cooler 43, transfers thereto another part of heat energy (which can also be recovered and used for any useful purpose) and then undergoes a second cooling, thus ending up in ideal conditions for the continuity of the cycle.

(99) Detailed Description of the Use of the New Pulsating Heat Cycle with an Already Known Drive Unit 1 (with Four Pistons).

(100) With reference to FIG. 11, in order to describe the functions of the new pulsating heat cycle according to the present inventive idea, it is necessary to start off by noting that in the drive unit 1, in each of the four periodically variable-volume chambers 13, 13, 14, 14 (each delimited by the two pistons adjacent to each other and rotating inside the annular cylinder), the diversified intake, compression, expansion and expulsion functions are performed periodically.

(101) For the sake of simplicity, in the following description, the path followed by the thermal fluid in the different sections of the heat engine 51 will be explained as if a single complete heat cycle were involved. In reality, for each revolution angle of 90? of the drive shaft (with a total revolution angle of 360?) four complete heat cycles are carried out.

(102) Every heat cycle, in its complete form (apart from start-up), is carried out continuously in the following phases of thermodynamic variation of the fluid: intake of the cooled fluid, compression of the fluid taken in, accumulation of the compressed fluid, preheating of the compressed fluid, superheating of the compressed-preheated fluid, expansion of the superheated fluid (and corresponding production of useful work), expulsion of the spent fluid, recovery of heat energy from the spent fluid and cooling of the spent fluid (with possible recovery of heat for different uses), as described below.

(103) With reference to FIGS. 2b,11, in an application of the drive unit 1 (with four pistons), illustrated purely by way of non-limiting example, the heat engine 51 according to the present inventive idea is configured so as to operate with the new pulsating heat cycle using any thermal fluid suited to the purpose (for example: air, nitrogen, helium, hydrogen, etc).

(104) The heat engine 51 is started up in the following manner: the burner 40 is activated and, via the heater 41, heats the thermal fluid contained in the serpentine 41a up to a preset minimum temperature; when the thermal fluid contained in the serpentine 41a has reached the preset minimum temperature, the primary shaft 17 and the whole transmission system which moves the six pistons 7a, 7b, 7c, 9a, 9b, 9c are made to start rotating by a specific starter (not represented in the figure, but which could also be the same electric generator connected to the primary shaft 17 of the drive unit 1), thereby creating the preliminary condition for initiating up the cycle; at this point the burner 40 is activated and, via the heater 41, heats the thermal fluid contained in the serpentine 41a up to a preset maximum temperature, thereby creating the conditions for the start-up and normal, continuous operation of the heat engine 51.

(105) With reference to FIG. 11, in the position in which the pistons are located, the following main phases can be identified:

(106) Phase of Intake of the Cooled Thermal Fluid.

(107) On leaving the cooler 43, the thermal fluid travels through the conduit 43 and after passing through the intake opening 15, is drawn into the chamber 13 as result of the moving away of the two pistons 9b-7b.

(108) Phase of Compression of the Thermal Fluid Taken in.

(109) As the two pistons 7b-9a move nearer, the thermal fluid (taken in during the previous cycle) is compressed and the temperature thereof increases.

(110) Phase of Accumulation of the Compressed Thermal Fluid.

(111) The compressed fluid, after passing through the discharge opening 16, the conduit 44 and the check valve 44a, is conveyed into the compensating tank 44, where it remains available for immediate use in the subsequent phases.

(112) Phase of Preheating of the Compressed Thermal Fluid.

(113) When, as a result of the input of the heated thermal fluid into the chamber 13, the pressure of the thermal fluid circulating in the serpentine 41a falls below that of the compensating tank 44, the fluid, after passing through the check valve 44b, flows through the conduit 44 and, whilst travelling through the entire serpentine 42a in the section 42-42, acquires heat energy from the regenerator 42 until arriving at the heating serpentine 41a.

(114) The heat engine 51 can comprise, in addition or as an alternative to the check valve 44b, a check valve 44c, interposed between the outlet 42 of the serpentine 42a and the inlet of the heating serpentine 41a.

(115) Phase of Superheating of the Compressed-Preheated Thermal Fluid.

(116) The burner 40 (fed with any type of fuel) supplies heat energy to heater 41 (which, instead of the burner 40, can also use other heat sources: solar energy, residual energy from industrial processes, etc.), so that on passing through the entire serpentine 41a, the compressed-preheated thermal fluid undergoes a rapid increase in temperature and pressure.

(117) Phase of Expansion of the Superheated Thermal Fluid.

(118) When the piston 7a, rotating in the annular cylinder in the direction of motion indicated by the arrows, opens the inlet opening 15 (thus also performing a valve function) the superheated thermal fluid, after travelling through the conduits 41, enters the expansion chamber 13, in which it can expand, causing the pistons to rotate and producing useful work (which may be used to produce electricity or for any other purpose).

(119) Phase of Expulsion of the Spent Thermal Fluid.

(120) As the pistons 7a-9b move nearer, the chamber 14 is reduced in volume and the spent thermal fluid (already expanded in the previous cycle), after passing through the discharge opening 16 and through the conduit 46, is expelled from the drive unit 1 toward the regenerator 42.

(121) Phase of Recovery of Heat Energy from the Spent Thermal Fluid.

(122) The spent thermal fluid, expelled from the drive unit 1, while passing through the regenerator 42, transfers thereto part of the heat energy still possessed and thus undergoes a first cooling.

(123) Phase of Cooling of the Spent Fluid.

(124) The thermal fluid leaving the regenerator 42, travels through the conduit 46 and, while passing through the cooler 43, transfers thereto another part of heat energy (which can also be recovered and used per any useful purpose) and then undergoes a second cooling, thus ending up in ideal conditions for the continuity of the cycle.

(125) Detailed Description of a New Pneumatic Motor (with Six Pistons).

(126) With reference to FIGS. 2b and 12, the pneumatic motor 61, according to the present inventive idea, is configured so as to employ a drive unit 1 which, as a working fluid, uses compressed air.

(127) Start-Up

(128) When it is desired to start up the engine, the primary shaft 17 of the drive unit 1 and the whole transmission system which moves the six pistons 7a, 7b, 7c, 9a, 9b, 9c are made to start rotating by a specific starter (not represented in the figure) and the valve 46a (manual or motorized) is simultaneously opened. upon the rotation of the pistons 7a, 7b, 7c; 9a, 9b, 9c, the conditions of normal operation are established.

(129) The engine cycle substantially takes place, in a continuous manner, in the following main phases:

(130) Phase of Introduction-Expansion of the Compressed Air in the First Section.

(131) The very high-pressure compressed air contained in the tank 46, after passing through the conduits 46,46 (with the valve 46a open) and through the inlet opening 15, enters the first expansion chamber 13 of the drive unit 1 where, with the movement of the pistons 9a-7a, it can expand to produce a part of useful work.

(132) Phase of Expulsion of the Compressed Air from the First Section.

(133) The compressed air, which has already transferred a part of pressure in the previous cycle, forced also by the nearing of the two pistons 7a-9b and reduction in the volume of the chamber 14, passes through the discharge opening 16, leaves the drive unit 1 and, via the conduit 47, arrives at the first heater 47.

(134) Phase of First Heating of the Compressed Air.

(135) Continuing in its path, the compressed air coming from the first section passes through a first heater 47, in which it undergoes a temperature increase, and then, passing through the conduit 47 and through the inlet opening 15, it is reintroduced into the second expansion chamber 13 of the drive unit 1 where, with the movement of the pistons 9b-7b, it can expand to produce another part of useful work.

(136) Phase of Expulsion of the Compressed Air from the Second Section.

(137) The compressed air, which has already transferred a part of pressure in the previous cycle, forced also by the nearing of the two pistons 7b-9c and reduction in the volume of the chamber 14, passes through the discharge opening 16, leaves the drive unit 1 and, via the conduit 48, arrives at the second heater 48.

(138) Phase of Second Heating of the Compressed Air.

(139) Continuing in its path, the compressed air coming from the second section passes through the second heater 48 and then, passing through the conduit 48 and through the inlet opening 15, it is reintroduced into the third expansion chamber 13 of the drive unit 1 where, with the movement of the pistons 9c-7c, it can expand to produce another part of useful work.

(140) Alternative 1_Phase of Expulsion of the Compressed Air from the Third Section, without Cycle Continuity.

(141) The compressed air, which has already transferred a part of pressure in the previous cycle, forced also by the nearing of the two pistons 7c-9a and reduction in the volume of the chamber 14, passes through the discharge opening 16 and leaves the drive unit 1, where the conduit 49 ends and the spent compressed air is released into the surrounding atmosphere.

(142) Alternative 2_Phase of Expulsion of the Compressed Air from the Third Section, Maintaining Cycle Continuity with Other Drive Units Operating in a Cascade Mode.

(143) The compressed air, which has already transferred a part of pressure in the previous cycle, forced also by the nearing of the two pistons 7c-9a and reduction in the volume of the chamber 14, passes through the discharge opening 16, leaves the drive unit 1 and, via the conduit 49, arrives at the third heater 49.

(144) Phase of Third Heating of the Compressed Air.

(145) If the use of a second drive unit 1, operating in a cascade mode is provided for, the compressed air coming from the third section, continuing in its path, passes through the third heater 49 and then, on travelling through the conduit 49, can be reintroduced into the first expansion chamber of a second drive unit 1 (operating with the first in cascade fashion), continuing the expansion-heating cycles for an additional three stages and if necessary also repeating with other additional drive units 1.