Piston pump and motor

Abstract

A plunger pump or plunger motor includes a block accommodating a first cylindrical chamber and a plunger movable in this chamber and a drive shaft connected to this plunger, as well as a second cylindrical chamber and a control valve movable in this second cylindrical chamber. Holes O.sub.3 and O.sub.4 can alternately be brought into communication with the connection for the delivery pipe by the plunger and with a connecting hole for a pressure line. The control valve can establish a communication between the hole O.sub.2 and the connecting hole. The drive shaft is connected to a further plunger which is movable in a third cylindrical chamber in which there is a suction hole or delivery hole. The control valve can alternately establish a communication between the suction hole or delivery hole with a connecting hole for a suction pipe and the connecting hole for the pressure line.

Claims

1. A plunger pump or a plunger motor, comprising: a motor casing including a first cylindrical chamber; a plunger movable in the first cylindrical chamber and including a drive shaft attached to a first plunger side; and a valve, wherein a first plunger surface on the first plunger side is smaller than a second plunger surface on an opposite second plunger side, wherein a first hole and a second hole are provided in the motor casing at such a location that one of the first hole and the second hole is available on either side of the plunger in any position of the plunger, wherein the valve includes a valve casing including a second cylindrical chamber and a control valve movable in the second cylindrical chamber, wherein the valve establishes a communication between a first connecting hole for a delivery pipe and the second hole, wherein the valve casing includes a first further hole and a second further hole at such a location that one of the first further hole and the second further hole is available on either side of the control valve in any position of the control valve, wherein the motor casing includes a third hole and a fourth hole, wherein the third hole communicates with the first further hole in the valve casing and the fourth hole communicates with the second further hole in the valve casing, wherein the third hole and the fourth hole are alternatively connectable with the first connecting hole for the delivery pipe by the plunger, wherein the third hole and the fourth hole are alternatively brought into communication with an ambient atmosphere or with a second connecting hole for the delivery pipe by the plunger, wherein the motor casing further includes a fifth hole and a sixth hole which communicate with the ambient atmosphere or with the second connecting hole for the delivery pipe, and wherein the plunger alternatively establishes a communication between the third hole and the fourth hole and the fifth hole and the sixth hole.

2. A The plunger pump or plunger motor according to claim 1, wherein the delivery pipe feeds the plunger pump or the plunger motor.

3. A plunger pump or a plunger motor, comprising: a motor casing including a first cylindrical chamber; a plunger movable in the first cylindrical chamber and including a drive shaft attached to a first plunger side; and a valve, wherein a first plunger surface on the first plunger side is smaller than a second plunger surface on an opposite second plunger side, wherein a first hole and a second hole are provided in the motor casing at such a location that one of the first hole and the second hole is available on either side of the plunger in any position of the plunger, wherein the valve includes a valve casing including a second cylindrical chamber and a control valve movable in the second cylindrical chamber, wherein the valve establishes a communication between a first connecting hole for a delivery pipe and the second hole, wherein the valve casing includes a first further hole and a second further hole at such a location that one of the first further hole and the second further hole is available on either side of the control valve in any position of the control valve, wherein the motor casing includes a third hole and a fourth hole, wherein the third hole communicates with the first further hole in the valve casing and the fourth hole communicates with the second further hole in the valve casing, wherein the third hole and the fourth hole are alternatively connectable with the first connecting hole for the delivery pipe by the plunger, wherein the control valve establishes a communication between the second hole and the ambient atmosphere or a second connecting hole for the delivery pipe, wherein the control valve casing includes a third further hole which communicates with the ambient atmosphere or with the second connecting hole for the delivery pipe, and wherein the control valve establishes a communication between the second hole and the third further hole.

4. The plunger pump or plunger motor according to claim 3, wherein the delivery pipe feeds the plunger pump or the plunger motor.

5. A plunger pump or a plunger motor, comprising: a motor casing including a first cylindrical chamber; a plunger movable in the first cylindrical chamber and including a drive shaft attached to a first plunger side; and a valve, wherein a first plunger surface on the first plunger side is smaller than a second plunger surface on an opposite second plunger side, wherein a first hole and a second hole are provided in the motor casing at such a location that one of the first hole and the second hole is available on either side of the plunger in any position of the plunger, wherein the valve includes a valve casing including a second cylindrical chamber and a control valve movable in the second cylindrical chamber, wherein the valve establishes a communication between a first connecting hole for a delivery pipe and the second hole, wherein the valve casing includes a first further hole and a second further hole at such a location that one of the first further hole and the second further hole is available on either side of the control valve in any position of the control valve, wherein the motor casing includes a third hole and a fourth hole, wherein the third hole communicates with the first further hole in the valve casing and the fourth hole communicates with the second further hole in the valve casing, wherein the third hole and the fourth hole are alternatively connectable with the first connecting hole for the delivery pipe by the plunger, wherein a drive shaft is connected to a further plunger which is movable in a third cylindrical chamber which is located in a pump casing in which a suction hole and a delivery hole is present.

6. The plunger pump or plunger motor according to claim 5, wherein the control valve alternatively brings the suction hole or the delivery hole into communication with a third connecting hole for a suction pipe and a second connecting hole for the delivery pipe.

7. The plunger pump or plunger motor according to claim 6, wherein the valve casing is provided with a fourth further hole which communicates with the suction hole or delivery hole, as well as a fifth further hole which communicates with the third connecting hole for the suction pipe.

8. The plunger pump or plunger motor according to claim 6, wherein the third further hole communicates with the second connecting hole for the delivery pipe.

9. The plunger pump or plunger motor according to claim 5, wherein the plunger and the further plunger are attached at each other.

10. The plunger pump or plunger motor according to claim 5, wherein the delivery pipe feeds the plunger pump or the plunger motor.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

(1) The invention will be described in more detail based on embodiments of the plunger pump or plunger motor according to the invention while reference is made to the appended drawing figures, wherein:

(2) FIG. 1 illustrates a first embodiment of the plunger pump or plunger motor according to the invention arranged as a plunger pump at the end of the suction stroke;

(3) FIG. 2 illustrates the situation shown in FIG. 1 with a switched-over control valve;

(4) FIG. 3 illustrates the plunger pump or plunger motor at an end of a delivery stroke;

(5) FIG. 4 illustrates the situation shown in FIG. 3 with a switched-over control valve; and

(6) FIG. 5 illustrates a second embodiment of the plunger pump or plunger motor according to the invention arranged as a plunger motor.

DETAILED DESCRIPTION OF THE INVENTION

(7) FIGS. 1 to 4 illustrate a first embodiment of the plunger pump or plunger motor according to the invention arranged as a plunger pump shown in different stages of the pumping process. The plunger pump or plunger motor includes a motor casing 1A which accommodates a first cylindrical chamber 7 and a plunger 2 movable in this chamber. At a first side A of the plunger 2 a drive shaft 19 is attached, as a result of which the plunger surface on this first side A is smaller than on an opposite, second side B.

(8) The motor casing 1A is provided with a first hole O.sub.1 and a second hole O.sub.2 at such a location that in any position of the plunger 2 one hole is available on either side of the plunger.

(9) The plunger pump or plunger motor further includes a valve which has a valve casing 1B which accommodates a second cylindrical chamber 7B and a control valve 3 movable in this chamber. This control valve can provide that a first connecting hole 6 for a delivery pipe which communicates with the second hole O.sub.2.

(10) The valve casing 1B is provided with a first further hole F.sub.1 and a second further hole F.sub.2. These further holes are located at such a spot that in any position of the control valve 3 one further hole is available on either side of the control valve. The motor casing 1A is further provided with a third and a fourth hole O.sub.3 and O.sub.4. The third hole O.sub.3 communicates with the first further hole F.sub.1 in the valve casing, and the fourth hole O.sub.4 communicates with the second further hole F.sub.2 in the valve casing. The third and fourth holes O.sub.3 and O.sub.4 can be alternatively brought into communication with the first connecting hole 6 for the delivery pipe by the plunger 2.

(11) The first connecting hole 6 for the delivery pipe is in permanent communication with the first hole O.sub.1. The third and fourth holes O.sub.3 and O.sub.4 can be alternatively brought into communication with a second connecting hole 5 for the delivery pipe by the plunger 2.

(12) The motor casing 1A is further provided with a fifth and a sixth hole O.sub.5 and O.sub.6 which communicate with the second connecting hole 5 for the delivery pipe. The third and the fourth hole O.sub.3 and O.sub.4 can be alternatively brought into communication with the fifth and sixth hole O.sub.5 and O.sub.6 respectively by the plunger 2. The control valve 3 can establish a communication between the second hole O.sub.2 and the second connecting hole 5 for the delivery pipe.

(13) The valve casing 1B is provided with a third further hole F.sub.3 which communicates with the second connecting hole 5 for the delivery pipe. The drive shaft 19 is connected to a further plunger 2a which is movable in a third cylindrical chamber 8 which is accommodated in a pump casing 1C in which a suction or delivery hole 9 is present.

(14) The control valve 3 can alternatively establish a communication between the suction hole or delivery hole 9 and a third connecting hole 4 for a suction pipe and the second connecting hole 5 for a delivery pipe. The valve casing 1B is provided with a fourth further hole F.sub.4 which communicates with the suction hole or delivery hole 9, as well as a fifth further hole F.sub.6 which communicates with the third connecting hole 4 for the suction pipe. The third further hole F.sub.3 communicates with the second connecting hole 5 for the delivery pipe.

(15) The motor casing 1A, the valve casing 1B and the pump casing 1C are constituted by a single block 1 in which the first, the second and the third cylindrical chambers 7, 7B and 8 are located. The block 1 is provided with three connecting holes 4, 5 and 6 to which the suction pipe, the delivery pipe and the pressure pipe can be connected. In the block 1 channels 12, 13, 16 and 17 are provided which connect the holes O.sub.1, O.sub.2, O.sub.3, O.sub.4, O.sub.5 and O.sub.6 and further holes F.sub.1, F.sub.2, F.sub.3 and F.sub.4 to each other and to the three connecting holes. The plunger 2 and the further plunger 2a constitute a whole.

(16) The plunger pump or plunger motor includes no more than two moving parts, that is to say, the plunger 2 with attached to it the further plunger 2a, and the control valve 3. The plunger 2 with the further plunger 2a attached to it is constituted by two parts, on the left there is the pumping part 2a and 2b and on the right there is the motor part 2c and 2d. The plunger and the control valve are coupled hydraulically, thus complex mechanisms and mechanisms subject to wear are absent.

(17) The ratio of pump diameter to motor diameter determines the lift of the pump and/or the number of strokes, thus the pump flow rate. The higher the difference in pressure over the motor with equal pump lift, the higher the pump flow rate.

(18) The feed of the motor takes place through the first connecting hole 6 by means of a medium that has a higher pressure than the pump pressure. This may be liquid, gas or a two phase mixture.

(19) The operation of the plunger pump or plunger motor will be further described with reference to the FIGS. 1 to 4. In FIG. 1 the position of the control valve 3 and plunger 2 is shown substantially at the end of the suction stroke at the moment where the control valve 3 is going to be changed over and the slot 2b in plunger 2 starts to open the channel 12 so that a connection is created between channel 12 and channel 13 so that the pressure on the left hand side of the control valve 3 will decrease rapidly to the pump delivery pressure prevailing in the second connecting hole 5 for the delivery pipe.

(20) A little later the high pressure that prevails in the cylindrical chamber 7 (this chamber forms a hydropneumatic compression spring) comes through channel 16 to the right hand side of the control valve 3 and will switch the latter over in a rapid manner. FIG. 2 shows the situation in switched-over position.

(21) Even before the motor side of the plunger 2 has reached its end position, there is already the higher pressure in channel 16 and the plunger will commence the delivery stroke. In the left hand position there is a constant higher pressure on the motor part of the plunger 2 through slot 3d in the control valve and the plunger 2 will push away the liquid in the cylindrical chamber 8 (this is the pump chamber) through the connecting hole 5 for the delivery pipe. By the end of the delivery stroke, see FIG. 3, the plunger 2 is decelerated because the plunger is to push away the liquid in chamber 11 through a narrow channel 10. If the plunger 2 passes the third hole O.sub.3 of channel 12, high-pressure medium will flow through the connecting hole 6 in the cylindrical chamber 7 (the compression spring) to the left hand side of the control valve 3. On the right hand side of the control valve 3 the pressure can be lowered through channel 15, slot 2d, channel 17 to the connection 5 for the delivery pipe.

(22) The control valve 3 changes over (cf. FIG. 4) and will discharge the motor of the pressure by opening up the channel 16 through slot 3c and channel 13 to the connecting hole 5 for the delivery pipe where the pump delivery pressure prevails. The pressure in the cylindrical chamber 7 (compression spring) will now push the plunger 2 to the right and thus draw liquid into the cylindrical chamber 8 (pump chamber) through the connecting hole 4.

(23) Disc 3a functions as a change-over cock so as to have the liquid flow correctly during the suction stroke and delivery stroke. The discs 3b are used for balancing of pressure. For equalizing the chambers around these discs, the valve has a bore 3e.

(24) FIG. 5 illustrates a second embodiment of the plunger pump or plunger motor according to the invention, arranged as a plunger motor this time. All parts similar to those of the first embodiment or having a similar function to those of the first embodiment are referred to by like reference numerals. In this embodiment the pump section is lacking and the drive shaft 19 extends to beyond the block 1. This drive shaft is driven by the plunger 2 and can in its turn drive a shaft for example via a slotted link mechanism. Furthermore, the third and fourth holes O.sub.3 and O.sub.4 can alternately be brought into communication with the ambient atmosphere 18 in lieu of with a connecting hole for a delivery pipe.

(25) Though the invention has been described in the foregoing with reference to the drawings, it is appreciated that the invention is not by any manner or means restricted to the embodiment shown in the drawings. The invention also extends to all embodiments deviating from the embodiment shown in the drawings within the spirit and scope defined by the appended claims.