Abstract
Provided is a dual venturi having: a tubular part; a body part, for opening/closing the flow of secondary air by rotating in the horizontal plane and vertical plane directions, the horizontal plane direction being the cross-sectional direction of the tubular part and the vertical plane direction being perpendicular to the horizontal plane; a central passageway, becoming the passageway for primary air; a damper part, and a damper part-side secondary gas outlet; a driving part, for rotationally driving the damper part in the horizontal and vertical planes; a gas inlet-side primary gas outlet connected openly to the damper part-side primary gas outlet; and a gas inlet for introducing gas into the tubular part via the damper part, which openly connects selectively to the damper part-side secondary gas outlet on the basis of the rotational position of the damper part, and for forming the rotational shaft of the damper part along with the rotational shaft of the driving part.
Claims
1. A dual venturi comprising, a tubular part, as a circular duct through which air and gas pass through, having a primary gas inlet; a damper part comprising: a body part located in the tubular part for opening/closing a secondary air flow by rotating in horizontal plane and vertical plane directions, the horizontal plane direction being a cross-sectional direction of the tubular part and the vertical plane direction being perpendicular to the horizontal plane, a cutout part which is a removed portion of the body part, becoming a primary gas passageway in an axial direction of the tubular part via a passageway formed together with an inner surface of the tubular part when the body part is placed in the horizontal plane direction, and a damper part-side secondary gas outlet; a driving part, connected to a left lateral surface of the damper part via a rotational shaft, for rotationally driving the damper part in the horizontal and vertical planes; and a secondary gas inlet for introducing a secondary gas into the tubular part via the damper part through a gas inlet-side secondary gas outlet, which connects selectively to the damper part-side secondary gas outlet on the basis of a rotational position of the damper part, wherein the secondary gas inlet is cylindrically shaped, and is inserted into a right lateral surface of the damper part, wherein a central axis of the rotational shaft is coaxial with a central axis of the secondary gas inlet such that the body part is rotated about the secondary gas inlet by the driving part, and wherein the primary gas inlet faces the cutout part when the body part is placed in the horizontal direction.
2. The dual venturi as claimed in claim 1, wherein the driving part comprises a synchronous motor, and wherein the rotational shaft of the driving part is a rotational shaft of the synchronous motor.
3. The dual venturi as claimed in claim 1, wherein the gas inlet-side secondary gas outlet is connected to the damper part-side secondary gas outlet when the body part is vertically positioned.
4. The dual venturi as claimed in claim 1, wherein the driving part comprises a limit switch indicating the vertical position and horizontal position of the damper part.
5. The dual venturi as claimed in claim 1, wherein the tubular part includes an upper portion, a central portion, and a bottom portion, and wherein the central portion has a relatively small diameter such that air passing through the central portion is accelerated and creates a relative vacuum through a venturi effect.
6. The dual venturi as claimed in claim 1, wherein the damper part-side secondary gas outlet is formed on an outer surface of the body part, such that the damper part-side secondary gas outlet faces upwardly when the damper part is rotated into the horizontal plane.
7. The dual venturi as claimed in claim 1, wherein the damper part-side secondary gas outlet is formed on an outer surface of the body part, such that the damper part-side secondary gas outlet faces both upwardly and downwardly when the damper part is rotated into the horizontal plane.
8. The dual venturi as claimed in claim 6, wherein only one gas inlet-side secondary gas outlet is formed on the gas inlet part, and wherein the damper part-side secondary gas outlet connects to the only one gas inlet side secondary gas outlet when the damper part is rotated into the vertical plane.
9. The dual venturi as claimed in claim 6, wherein two inlet-side secondary gas outlets are formed on the gas inlet part, and wherein the damper part-side secondary gas outlet connects to both of the two inlet-side secondary gas outlets when the damper part is rotated into the vertical plane.
Description
BRIEF DESCRIPTION OF THE DRAWINGS
(1) FIG. 1 is an exploded perspective view showing the dual venturi according to the first embodiment of the present invention.
(2) FIG. 2a shows a first embodiment of the present invention, that is a longitudinal sectional view of the dual venturi with the damper part in a closed state; and FIG. 2b is a longitudinal sectional view showing the dual venturi with the damper part in an open state.
(3) FIG. 3a, FIG. 3b and FIG. 3c show a first embodiment of the present invention, that is a diagram showing the damper part in the closed state. FIG. 3a is a perspective view of the dual venturi, FIG. 3b is a planar sectional view of the dual venturi and FIG. 3c is a sectional view showing the positional relationship between the gas inlet and the secondary gas outlets of the damper part.
(4) FIG. 4a, FIG. 4b and FIG. 4c show a first embodiment of the present invention, that is a diagram showing the damper in the open state. FIG. 4a is a perspective view of the dual venturi, FIG. 4b is a planar sectional view of the dual venturi and FIG. 4c is a sectional view showing the positional relationship between the gas inlet and the secondary gas outlets of the damper part.
(5) FIG. 5a and FIG. 5b show the positional relationship between gas inlet-side secondary gas outlet and the damper part at the limit switch of the driving part. FIG. 5a is a planar view of the limit switch and FIG. 5b is a lateral view of the limit switch.
(6) FIG. 6 is an exploded perspective view of the dual venturi according to the second embodiment of the present invention.
(7) FIG. 7a shows a second embodiment of the present invention, that is a longitudinal sectional view of the dual venturi with the damper in a closed state; and FIG. 7b is a longitudinal sectional view showing the dual venturi with the damper in a open state.
(8) FIG. 8a, FIG. 8b and FIG. 8c show a second embodiment of the present invention, that is a diagram showing the damper in the closed state. FIG. 8a is a perspective view of the dual venturi, FIG. 8b is a planar sectional view of the dual venturi and FIG. 8c is a sectional view showing the positional relationship between the secondary gas inlet and the secondary gas outlets of the damper part.
(9) FIG. 9a and FIG. 9b show a second embodiment of the present invention, that is a diagram showing the damper in the open state. FIG. 9a is a perspective view of the dual venturi, and FIG. 9b is a sectional view showing the positional relationship between the secondary gas inlet and the secondary gas outlets of the damper part.
(10) FIG. 10a and FIG. 10b show the positional relationship between the secondary gas inlet-side secondary gas outlet and the damper part at the limit switch of the driving part. FIG. 10a is a planar view of the limit switch and FIG. 10b is a lateral view of the limit switch.
(11) FIG. 11 is a drawing showing prior art.
DESCRIPTION OF THE PREFERRED EMBODIMENTS
(12) Hereinafter, the first embodiment of the present invention will be described with reference to the accompanying drawings.
(13) First, the overall structure of the dual venturi is explained with reference to FIG. 1, FIG. 2a and FIG. 2b. FIG. 1 is an exploded perspective view defining the dual venturi according to the first embodiment of the present invention, FIG. 2a shows a first embodiment of the present invention, that is a longitudinal sectional view of the dual venturi with the damper in a closed state, and FIG. 2b is a longitudinal sectional view showing the dual venturi with the damper in a open state, respectively.
(14) The dual venturi according to the present invention comprises a tubular part (40) as a passageway duct through which air passes through; a damper part (20) for opening/closing the secondary air passageway that is formed on the tubular part (40) and extends in the direction of the lower portion (43) to the upper portion (44) of the tubular part (40); a driving part (10) in which the rotational shaft (15) of the motor, that is inserted through the tubular part-side second hole (42) while being connected to the lateral surface of the damper part (40), is connected to the damper part-side first hole (23) to rotate the damper part (20); and a cylindrical gas inlet (30) inserted through the first hole (41) of the tubular part (40) and connected to the damper part-side second hole (27) (Refer to FIG. 3c) to provide primary gas and secondary gas through the damper part (20).
(15) As illustrated in FIG. 1, the tubular part (40) has a central diameter that is smaller than the diameter of both ends of the higher and lower portions, thus the central passageway is narrowly formed. This configuration can be more clearly understood from FIG. 2a and FIG. 2b. However, the shape of the tubular part (40) can be a cylindrical shape with equal upper and lower portions, and the present invention is not particularly limited to this shape.
(16) The damper part (20) comprises an overall donut-shaped body part (29), which has a central passageway (21) formed in the central thereof, and a damper part-side secondary gas outlet (22) having three slot-type holes, through which secondary gas is discharged, is formed on the upper surface of the body part. The body part (29) corresponding thereto can also have a secondary gas outlet. That is, it is seen in FIG. 2a that the damper part-side secondary gas outlet (22) formed on the upper surface of the damper part (20) is also formed on the corresponding lower portion. The number of the slot-type holes can be suitably selected according to need, and its shape can also be varied.
(17) Further, the central passageway (21) of the damper part (20) is the passageway through which the primary air passes through at closed state. As a first embodiment of the present invention, it is seen that it is a venturi shape similar to the tubular part (40) shape that is the passageway for the secondary air. As shown in FIG. 2a and FIG. 2b, the central passageway (21) of the damper part (20) has a damper part-side primary gas outlet (24) through which primary gas is discharged.
(18) The gas inlet (30) is cylindrically shaped, and is connected to the damper part-side second hole (27) via insertion through the tubular part-side first hole (41). Here, the gas inlet (30) does not rotate but the damper part (20) can, thus the gas inlet (30) also functions as a stationary shaft to rotate the damper part (20) together with the rotational shaft (15).
(19) The damper part-side opening of the gas inlet (30) forms the gas inlet-side primary gas outlet (33) and maintains an open connection to the damper part-side primary gas outlet (24) at all times.
(20) A gas inlet-side secondary gas outlet (32) having an identical shape to the damper part-side secondary gas outlet (22) is formed on the circumference of the area near the damper part-side of the gas inlet (30). The gas inlet part-side secondary gas outlet (32) is also symmetrically shaped and can form outlets on both sides of the pipe or form an outlet only on one side. FIG. 2a illustrates a closed state of the damper part (20), that is the state in which the upper and lower passageways of the tubular part (40) are blocked and only the central passageway (21) of the damper part (20) is used as the primary air passageway of the tubular part (40). In other words, the state in which the damper part (20) is placed in the cross-sectional direction, that is the horizontal plane of the tubular part (40), only the gas inlet-side primary gas outlet (33) is open towards the damper part-side primary gas outlet (24), and the gas inlet part-side secondary gas outlet (32) is closed.
(21) FIG. 2b illustrates opened state of the damper part (20), that is the state in which the upper and lower passageways of the tubular part (40) are open, thus most of the horizontal plane passageway in the cross-sectional direction of the tubular part (40) is substantially used as the air passageway, the so-called secondary air passing state. Here, the damper part (20) is placed in the vertical plane that is perpendicular to the horizontal plane, and the gas inlet-side primary gas outlet (33) as well as the gas inlet-side secondary gas outlet (32) are both open towards the damper part-side secondary gas outlet (22). As a result, all functions of the first step distribution and second step distribution can be executed.
(22) Hereafter, operation of the dual venturi according to the first embodiment of the present invention will be described in detail with reference to FIG. 3a to FIG. 5b. Parts not thoroughly explained in the above detailed description will be explained through the additional configuration.
(23) First, FIG. 3a, FIG. 3b and FIG. 3c show a first embodiment of the present invention, that is a diagram showing the closed state of the damper (20). FIG. 3a is a perspective view of the dual venturi, FIG. 3b is a planar sectional view of the dual venturi and FIG. 3c is a sectional view showing the positional relationship between the gas inlet and the secondary gas outlets of the damper part.
(24) As shown in the perspective view of FIG. 3a, when the damper part (20) is closed, the positional relationship between the tubular part (40) and the damper part (20) is equal to when the damper part (20) blocks the entire upper and lower air passageways of the tubular part (40), and only the central passageway (21) of the damper part (20) substantially becomes the air passageway (primary air passageway) of the tubular part (40). In other words, the damper part (20) is placed in the horizontal plane in the cross-sectional direction of the tubular part (40), and at this time, as shown in FIG. 3b, only the gas inlet-side primary gas outlet (33) is connected to the damper part-side primary gas outlet (24) so that primary gas (51) flows through the central passageway (21), and the gas inlet-side secondary gas outlet (32) is blocked by the wall of the damper part-side second hole (27) and thus closed, as shown in FIG. 3c. That is, a small quantity of relatively low level primary air and primary gas flow through the tubular part in the closed state.
(25) FIG. 4a, FIG. 4b and FIG. 4c show a first embodiment of the present invention, that is a diagram showing the open state of the damper. FIG. 4a is a perspective view of the dual venturi, FIG. 4b is a planar sectional view of the dual venturi and FIG. 4c is a sectional view showing the positional relationship between the gas inlet and the secondary gas outlets of the damper part.
(26) As shown by the perspective view of FIG. 4a, when the damper part (20) is opened, the positional relationship between the tubular part (40) and the damper part (20) is equal to when the damper part (20) substantially opens the entire upper and lower air passageways of the tubular part (40), thereby the entire passageway becomes the air passageway (secondary air passageway). In other words, the damper part (20) is placed upright perpendicularly to the horizontal plane in the closed state, that is the vertical plane to the cross-sectional direction of the tubular part (40). At this time, as shown in FIG. 4b, the gas inlet-side primary gas outlet (33) is connected to the damper part-side primary gas outlet (24), so that the primary gas (51) flows through and also the gas inlet-side secondary gas outlet (32) is opened to let the secondary gas (52) flow out.
(27) Referring to FIG. 4c, the gas inlet-side secondary gas outlet (32) and the damper part-side secondary gas outlet (22) formed on the wall of the damper part-side second hole (27) correspond to each other and thereby are connected.
(28) In this embodiment, the gas inlet-side secondary gas outlet (32) is formed only on one part of the circumference diameter such that only one lateral surface (for instance, the upper direction-side surface of the upper and lower directions of the tubular part (40)) of the damper part (20) releases secondary gas (52). However, for instance, the gas inlet-side secondary gas outlet (32) can be installed on the opposite side (that is, 180) of the cylindrical gas inlet (30) wall circumference to release secondary gas in the upper and lower directions of the damper part (20).
(29) In this embodiment, the damper part-side primary gas outlet (24) has a cross-sectional area that is set smaller than the opening of the gas inlet (30) side primary gas outlet (33), and the mutual opening ratio thereof can be suitably determined as necessary.
(30) FIG. 5a and FIG. 5b show the positional relationship between the gas inlet-side secondary gas outlet and the damper part at the limit switch of the driving part. FIG. 5a is a planar view of the limit switch and FIG. 5b is a lateral view of the limit switch, respectively.
(31) In the limit switch (11) shown in FIG. 5a, reference signs 11a and 11b show the position points of the damper part-side secondary gas outlet, 11c and 11d respectively show the position points of the gas inlet-side secondary gas outlet, 11g shows the damper part-side positional probe, and 11h shows the gas inlet-side positional probe, respectively. One of the damper part-side secondary gas outlet position points (11a)(11b) is positioned at the damper part-side positional probe (11g), and in the same manner if one of the gas inlet-side secondary gas outlet position points (11c)(11d) corresponds to the gas inlet-side positional probe (11h), secondary air and secondary gas are blocked, as shown in FIG. 3c. That is, it shows the state in which the damper part (20) is at the horizontal plane position.
(32) Further, on the contrary, if one of the gas inlet-side secondary gas outlet position points (11c)(11d) corresponds to the damper part-side positional probe (11g), and at the same time one of the damper part-side secondary gas outlet position points (11a)(11b) is positioned at the gas inlet-side positional probe (11h), the secondary air and secondary gas are open to flow through the tubular part (40), as shown in FIG. 4. That is, this shows the state in which the damper part (20) is vertically positioned.
(33) Referring to FIG. 5b, a synchronous motor is used as the motor (13) included in the driving part (10) and the rotational shaft (15) of the direct motor (13) can be connected to the damper part-side first hole (23). Thus, components necessary for the AC motor in the prior art such as a wire, or return spring can be removed, allowing the dual venturi of the present invention to be more simplified compared to the prior art.
(34) Hereafter, the second embodiment of the present invention will be described in detail with reference to FIG. 6 to FIG. 10b. Configurations substantially identical to the first embodiment are indicated with the same reference signs.
(35) First, the second embodiment showing the overall structure of the dual venturi according to the present invention will be described in detail with reference to FIG. 6, FIG. 7a and FIG. 7b. FIG. 6 is an exploded perspective view defining the dual venturi according to the second embodiment of the present invention, FIG. 7a shows a second embodiment of the present invention, that is a longitudinal sectional view of the dual venturi with the damper in a closed state, and FIG. 7b is a longitudinal sectional view showing the dual venturi with the damper in an open state, respectively.
(36) The dual venturi according to the present invention comprises, a tubular part (40), that is a passageway duct through which air passes through, having a primary gas inlet (45) at the center of the lateral wall; a damper part (20) for opening/closing the secondary air passageway that is formed on the tubular part (40) and extends in the direction from the lower portion (43) to the upper portion (44) of the tubular part (40); a driving part (10) connected to the lateral surface of the damper part (40), with the rotational shaft (15) of the motor, that is inserted through the tubular part-side second hole (42), being connected to the damper part-side first hole (23) to rotate the damper part (20); and a cylindrical secondary gas inlet (60) inserted through the first hole (41) of the tubular part (40) and connected to the damper part-side second hole (27) (Refer to FIG. 8c) to provide secondary gas through the damper part (20).
(37) As shown in FIG. 6, the tubular part (40) has a central diameter that is smaller than the diameter of both ends of the upper and lower portions, thus the central passageway is narrowly formed. This configuration can be more clearly understood from FIG. 7a and FIG. 7b. However, the shape of the tubular part (40) can be a cylindrical shape with equal upper and lower portions, and the present invention is not particularly limited to this shape.
(38) The damper part (20) comprises a body part (29) having an overall disk shape with a portion of it removed, and a cutout part (26) that is formed by the removed portion of the body part circumference, in which the upper surface of the body part (29) has a damper part-side secondary gas outlet (22) having four slot-type holes through which secondary gas flows out. The body part (29) corresponding thereto can also have a secondary gas outlet (22). That is, it is also seen on the lower portion corresponding to the secondary gas outlet (22). Further, four slot-type holes are shown, but its number can be suitably selected according to need and its shape can also be varied.
(39) At the closed state, the cutout part (26) of the damper part (20) forms the passageway for the primary air to move through together with the internal-side wall of the tubular part (40). It may also be venturi-shaped, similar to the shape of the tubular part (40) which forms the second air passageway in the second embodiment of the present invention. As shown in FIG. 7a and FIG. 7b, the end part of the secondary gas inlet (60) in contact with the damper side (20) is also closed by the sealing hole (28) of the damper part.
(40) The secondary gas inlet (60) is cylindrically shaped, and is connected to the damper part-side second hole (27) (Refer to FIG. 8c) via insertion through the tubular part-side first hole (41). Here, the secondary gas inlet (60) does not rotate but the damper part (20) can, thus the secondary gas inlet (60) also functions as a stationary shaft to rotate the damper part (20) together with the rotational shaft (15) of the motor. The damper part-side opening of the secondary gas inlet (60) is also closed by the sealing hole (28) as mentioned above, and a secondary gas inlet-side secondary gas outlet (32)) having an identical shape to the damper part-side secondary gas outlet (22) is formed on the circumference of the area near the damper part-side of the secondary gas inlet (60). The secondary gas inlet-side secondary gas outlet (32) is also symmetrically shaped and can form outlets on both sides of the pipe or form an outlet only on one side. FIG. 7a illustrates a closed state of the damper part (20), that is the state in which the upper and lower passageways of the tubular part (40) are closed and only the cutout part (26) of the damper part (20) is used as the primary air passageway of the tubular part (40). In other words, it is the state in which the damper part (20) is placed in the cross-sectional direction, that is the horizontal plane of the tubular part (40), only the primary gas inlet (45) is open towards the inner wall of the tubular part (40) (it maintains an open state at all times), and the secondary gas inlet-side secondary gas outlet (32) is closed.
(41) FIG. 7b illustrates the opened state of the damper part (20), that is the state in which the upper and lower passageways of the tubular part (40) are open, thus most of the horizontal plane passageway in the cross-sectional direction of the tubular part (40) is substantially used as the air passageway, the so-called secondary air passing state. Here, the damper part (20) is placed in the vertical plane that is perpendicular to horizontal plane, and the primary gas inlet (45) as well as the secondary gas inlet-side secondary gas outlet (32) are both open towards the damper part-side secondary gas outlet (22). As a result, all functions of the first step distribution and second step distribution can be executed.
(42) Next, operation of the dual venturi according to the second embodiment of the present invention will be described in detail with reference to FIG. 8a to FIG. 9b. Parts not thoroughly explained in the above detailed description will be explained through the additional configuration.
(43) First, FIG. 8a, FIG. 8b and FIG. 8c show a second embodiment of the present invention, that is a diagram showing the damper (20) in the closed state. FIG. 8a is a perspective view of the dual venturi, FIG. 8b is a planar sectional view of the dual venturi and FIG. 8c is a sectional view showing the positional relationship between the secondary gas inlet and the secondary gas outlets of the damper part.
(44) As shown in the perspective view of FIG. 8a, when the damper part (20) is closed, the positional relationship between the tubular part (40) and the damper part (20) is the state in which the upper and lower passageways of the tubular part (40) are closed by the damper part (20), and only the cutout part (26) of the damper part (20) and the arc shaped cross-sectional area formed by the interior wall of the tubular part are substantially used as the air passageway (first air passageway) of the tubular part (40). In other words, the state in which the damper part (20) is placed in the cross-sectional direction, that is the horizontal plane of the tubular part (40). Here, as shown in FIG. 8b, only the primary gas inlet part (45) is open towards the tubular part (40) (always at the opened state), thereby the primary gas flows through the tubular part (40) and the secondary gas inlet-side secondary gas outlet (32) is blocked by the damper part-side second hole (27) wall and closed, as shown in FIG. 8c. That is, during the closed state, a small amount of relatively low level primary air and primary gas flow through the tubular part. In this embodiment, the cutout part (45) and the primary gas inlet (45) face each other at the closed state of the damper part (20).
(45) FIG. 9a and FIG. 9b show a second embodiment of the present invention, that is a diagram showing the open state of the damper. FIG. 9a is a perspective view of the dual venturi and FIG. 9b is a sectional view showing the positional relationship between the secondary gas inlet and the secondary gas outlets of the damper part.
(46) As shown in the perspective view of FIG. 9a, when the damper part (20) is opened, the positional relationship between the tubular part (40) and the damper part (20) is the state in which the upper and lower passageways of the tubular part (40) are opened substantially by the damper part (20), thus the entire passageway becomes the air passageway (secondary air passageway). That is, the damper part (20) is placed perpendicularly to the horizontal plane at the closed state, in other words perpendicularly to the cross-sectional direction of the tubular part (40). Here, as shown in FIG. 9a, the primary gas (51) flows through the primary gas inlet (45) and the secondary gas inlet-side secondary gas outlet (32) is also opened to let the secondary gas flow out.
(47) Referring to FIG. 9b, the secondary gas inlet-side secondary gas outlet (32) and the damper part-side secondary gas outlet (22) formed on the damper part-side second hole (27) correspond to each other and are therefore connected.
(48) In this embodiment, the secondary gas inlet-side secondary gas outlet (32) is only formed on one side via the circumference diameter such that only one lateral surface (for instance, the upper direction-side surface of the upper and lower directions of the tubular part (40)) of the damper part (20) releases secondary gas. However, for instance, the secondary gas inlet-side secondary gas outlet (32) can also be installed on the opposite side (that is, 180) of the cylindrical secondary gas inlet (60) wall circumference, to release secondary gas in the upper and lower directions of the damper part (20).
(49) In this embodiment, the primary gas inlet (45) is configured to face the cutout part (26) of the damper part (20), but the angle or the top and bottom heights can be varied to not face the cutout part.
(50) FIG. 10a and FIG. 10b show the positional relationship between the secondary gas outlet of the secondary gas inlet and the damper part at the limit switch of the driving part, according to the second embodiment of the present invention. FIG. 10a is a planar view of the limit switch and FIG. 10b is a lateral view of the limit switch, respectively.
(51) In the limit switch (11) shown in FIG. 10a, reference signs 211a and 211b show the position points of the damper part-side secondary gas outlets, 211c and 211d respectively show the position points of the secondary gas inlet-side secondary gas outlets, 211g shows the damper part-side positional probe, and 211h shows the gas inlet-side positional probe, respectively. One of the damper part-side secondary gas outlet position points (211a)(211b) is positioned at the damper part-side positional probe (211g), and in the same manner if one of the secondary gas inlet-side secondary gas outlet position points (211c)(211d) corresponds to the secondary gas inlet-side positional probe (211h), secondary air and secondary gas are blocked, as shown in FIG. 8c. That is, it shows the state in which the damper part (20) is at the horizontal position.
(52) Further, on the contrary, if one of the secondary gas inlet-side secondary gas outlet position points (211c)(211d) corresponds to the damper part-side positional probe (211g), and at the same time one of the damper part-side secondary gas outlet position points (211a)(211b) is positioned at the secondary gas inlet-side positional probe (211h), the secondary air and secondary gas are opened to flow through the tubular part (40), as shown in FIG. 9b. That is, this shows the state in which the damper part (20) is vertically positioned.
(53) Referring to FIG. 10b, a synchronous motor is used as the motor (13) included in the driving part (10) and the rotational shaft (15) of the direct motor (13) can be connected to the damper part-side first hole (23). Thus, components necessary for the AC motor in the prior art such as a wire, or return spring can be removed, allowing the dual venturi of the present invention to be more simplified compared to the prior art.
(54) The above description defines a preferred embodiment of the present invention but is not limited thereto, and various modifications and other similar embodiments are possible by the skilled person in the art. For instance, the combination of the limit switch sets the secondary gas open state as when the damper part-side probe and the secondary gas inlet-side probe positions are against each secondary gas outlet positions. However, the opposite setting may be used as long as practically identical results are indicated. Further, the position of the primary gas inlet is set to face the cutout part of the damper part in the above embodiment, however, this may be varied according to the rotation angle and top and bottom positions of the tubular part. Thus, various modifications and embodiments that can be clearly expected are also within the scope of the present invention.
REFERENCE SIGNS
(55) 10: Driving Part, 11: Limit Switch, 11a: Damper Part-Side Secondary Gas Outlet Position Point 11b: Damper Part-Side Secondary Gas Outlet Position Point, 11c: Gas Inlet-Side Secondary Gas Outlet Position Point, 11d: Gas Inlet-Side Secondary Gas Outlet Position Point, 11g: Damper Part-Side Positional Probe, 11h: Gas Inlet-Side Positional Probe, 15: Rotational Shaft of the Motor, 20: Damper Part, 21: Central Passageway, 22: Damper Part-Side Secondary Gas Outlet, 23: Damper Part-Side First Hole, 24: Damper Part-Side Primary Gas Outlet, 26: Cutout Part, 27: Damper Part-Side Second Hole, 28: Damper Part-Side Sealing Hole, 29: Body Part, 30: Gas Inlet Part, 32: Gas Inlet-Side Secondary Gas Outlet, 33: Gas Inlet-Side Primary Gas Outlet, 40: Tubular Part, 41: Tubular Part-Side First Hole, 42: Tubular Part-Side Second Hole, 45: Primary Gas Inlet, 51: Primary Gas, 52: Secondary Gas, 60: Secondary Gas Inlet
