JP2007162662A - Pressurized fluid discharging device and pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump device reduced in rotating loss by preventing a frictional force from being increased by a seal. <P>SOLUTION: A vane pump comprises a pressure plate 17 disposed between a rotor 1 and a second side housing 6, a biasing means 18 biasing the pressure plate 17 to the rotor 1 side, and a pressurized fluid imparting means 20 guiding a discharge air into a cancel chamber 19 formed between the pressure plate 17 and the second side housing 6. The force in the side outer direction is generated in the pressure plate 17. The force in the side inner direction is generated in the pressure plate 17 by the high-pressure discharge pressure guided into the cancel chamber 19. Namely, the force in the side outer direction is canceled by the force in the side inner direction. By the cancel mechanism, the sealing performance can be secured even if a seal member is not strongly pressed against the rotor, and the rotating loss of the rotor 1 can be reduced. <P>COPYRIGHT: (C)2007,JPO&INPIT

Description

  The present invention relates to a pressurized fluid discharge device (for example, a pump device or a rotary engine) that discharges a pressurized fluid (high-pressure fluid) as the rotor rotates, and a pump that generates a suction negative pressure when the rotor rotates. More particularly, the present invention relates to a seal structure for a side surface of a rotor.

(Conventional technology)
As a conventional technique related to the seal structure of the side surface of the rotor, a technique disclosed in Patent Document 1 is known.
As shown in FIG. 4, Patent Document 1 is a technique related to the side seal of the rotor 1 in the vane pump. The ring-shaped seal member J1 is pressed against the outer peripheral edge of the rotor 1 by a spring J2, and the outer peripheral edge of the rotor 1 The first and second side housings 5 and 6 are sealed.

(Problems of conventional technology)
As the rotor 1 rotates, the pump device sucks the external fluid by changing the small space volume to the large space volume, pressurizes the sucked fluid by changing the large space volume to the small space volume, and discharges the fluid outside. Therefore, the internal pressure increases on the discharge side.
For this reason, even if a high discharge pressure acts on the discharge side, it is necessary to increase the urging force (spring force) of the spring J2 that presses the seal member J1 against the rotor 1 in order to ensure sealing performance.

However, when the seal member J1 is strongly pressed against the rotor 1, the friction between the rotor 1 and the seal member J1 increases, and the pump efficiency decreases.
In addition, since it is necessary to increase the driving force of the rotor 1, the driving device (for example, an electric motor) of the rotor 1 is increased in size to increase the size and cost.
Furthermore, since a large driving force is required for the rotor 1, energy consumption (for example, power consumption) of the driving device is increased.
JP 7-317679 A

  The present invention has been made in view of the above-described problems, and its object is to prevent an increase in frictional force even when a high pressure is applied on the discharge side, thereby enabling side sealing of the rotor, and rotation loss of the rotor. The present invention is to provide a pressurized fluid discharge device and a pump device that are small in size.

[Means of claim 1]
In the pressurized fluid discharge device employing the means of claim 1, the pressure plate is pressed against the rotor side by an urging means (spring or the like) to seal the side surface of the rotor and pressurized by the pressurized fluid applying means. A configuration is adopted in which the fluid is guided to a cancellation chamber formed between the pressure plate and the side housing.
Here, the high pressure between the rotor and the ring housing generates a force that pushes the pressure plate away from the rotor (a force outward in the side direction).
On the other hand, the pressure of the pressurized fluid guided to the cancellation chamber between the pressure plate and the side housing generates a force (force inward in the side direction) that presses the pressure plate toward the rotor.
Thus, in the technique of claim 1, the outward force in the side direction is canceled by the inward force in the side direction.
For this reason, even if a high pressure is applied to the discharge side, the sealing performance of the side surface of the rotor is increased without increasing the urging force of the urging means (spring, etc.) that urges the pressure plate that performs side sealing toward the rotor. Can be secured.
Even if a high pressure is applied to the discharge side, it is not necessary to increase the biasing force of the biasing means, so the friction of the rotor can be suppressed, and the rotor rotation loss (in the case of a pump device, pump efficiency loss, rotary In the case of an output device such as an engine, output loss) can be reduced.

[Means of claim 2]
A pressurized fluid discharge device that employs the means of claim 2 is a pump device that sucks and discharges fluid by volume fluctuation accompanying rotation of the rotor.
This can prevent a decrease in pump efficiency.
Further, since the rotation loss of the rotor can be reduced, the driving force of the rotor can be reduced, the rotor driving device (for example, an electric motor) can be reduced in size, and the physique of the pump device can be reduced. . In addition, the cost can be reduced by downsizing the rotor driving device (for example, an electric motor).
Furthermore, since the driving force of the rotor can be reduced, energy consumption (for example, power consumption) of the driving device (for example, electric motor) can be suppressed.

[Means of claim 3]
The pump device adopting the means of claim 3 covers one axial side surface of the pump chamber and is disposed between the rotor and the side housing, and is caused by the suction negative pressure generated in the pump chamber surrounded by the rotor and the ring housing. The side surface of the rotor is sealed by a flexible membrane member that is drawn toward the pump chamber.
The film-like member drawn to the pump chamber side ensures the sealing performance of the rotor side surface. That is, the sealing performance of the side surface of the rotor can be ensured without being affected by the discharge pressure of the rotor.
Thus, since there is no urging means for strongly pressing the seal member against the rotor on the discharge pressure side, it becomes possible to suppress the friction of the rotor and prevent the pump efficiency from being lowered.
Further, since the friction of the rotor is suppressed, the driving force of the rotor can be reduced. As a result, the rotor drive device (for example, an electric motor) can be reduced in size, and the size of the pump device can be reduced, and the cost can be reduced.
Furthermore, since the driving force of the rotor can be reduced, energy consumption (for example, power consumption) of the driving device (for example, electric motor) can be suppressed.

[Means of claim 4]
In the pump device employing the means of claim 4, the membrane member is disposed in a minute clearance between the rotor and the side housing.
As a result, even if the film member is separated from the rotor by discharge pressure on the discharge side, the gap between the film member and the rotor can be kept small, and the sealing performance of the side surface of the rotor can be kept high.

[Means of claim 5]
In the pump device adopting the means of claim 5, the membrane member is sandwiched and fixed between the axial direction of the ring housing and the side housing.
Thereby, the sealing performance between the ring housing and the side housing can be ensured by the membrane member.

[Means of claim 6]
A pump apparatus employing the means of claim 6 comprises pressurized fluid applying means for guiding the pressurized fluid to the clearance between the membrane member and the side housing.
As a result, the action of the film member separating from the rotor on the discharge side is suppressed, and the sealing performance of the side surface of the rotor can be improved.

  The pressurized fluid discharge device of the best mode 1 is suitable for use in pump devices (various pumps such as vane pumps and trochoid pumps) and side seals of rotary engines. The rotating rotor and the radial direction of the rotor A ring housing covering the rotor and a side housing covering the direction of the rotation axis of the rotor, and disposed between the rotor and the side housing, and a housing provided with a discharge passage for guiding pressurized fluid between the rotor and the ring housing to the outside. A pressure plate fitted to the inner wall surface of the ring housing and supported so as to be slidable in the axial direction; urging means for urging the pressure plate toward the rotor; and pressurized fluid between the pressure plate and the side housing. And a pressurized fluid applying means that leads to a cancellation chamber formed therebetween.

  The pump device (various pumps such as a vane pump and a trochoid pump) of the best mode 2 includes a rotating rotor, a ring housing that covers the radial direction of the rotor, and a side housing that covers the rotational axis direction of the rotor. A housing that generates suction negative pressure in the pump chamber surrounded by the cylinder, covers one axial side surface of the pump chamber, is sandwiched between the rotor and the side housing, and is drawn toward the pump chamber by the suction negative pressure A flexible membrane member.

A first embodiment in which the present invention is applied to a vane pump will be described with reference to FIG.
(Configuration of Example 1)
The vane pump shown in the first embodiment is used, for example, for checking the leakage of evaporated fuel in the canister or for sending evaporated fuel held in the canister to the intake pipe when the intake negative pressure is low.

The vane pump is an example of a pump device that sucks and discharges fluid (air in this embodiment) by a volume change accompanying the rotation of the rotor 1, and is also an example of a pressurized fluid discharge device.
The vane pump includes a housing that is fixed to a vehicle, a rotor 1 that rotates within the housing, a plurality of vanes 2 that are slidably supported in a radial direction of the rotor 1, and an electric motor (drive device) that rotationally drives the rotor 1. 3) and a side seal structure described later.

The housing includes a ring housing 4 that covers the radial direction of the rotor 1 and side housings (first and second side housings 5 and 6) that cover the rotation axis direction of the rotor 1. The ring housing 4 and the first and second side housings 5 and 6 may be separate from each other or may be partially integrated. Specifically, in the first embodiment, a housing including a cam housing in which a ring housing 4 and a first side housing 5 are integrally formed and a second side housing 6 is disclosed.
The cam housing (the ring housing 4 and the first side housing 5) and the second side housing 6 employ a structure in which the electric motor 3 is pressed against the motor flange 8 to which the electric motor 3 is fixed by a bolt 7 and is fixed in the axial direction. ing.

The ring housing 4 includes a cylindrical cam surface 12 that is eccentric with respect to the rotating shaft 11 of the electric motor 3.
The rotor 1 has a substantially cylindrical shape, is disposed inside the ring housing 4, and forms a substantially crescent-shaped pump chamber 13 formed by a double circular gap eccentric with the cam surface 12. The rotor 1 is fitted into the rotary shaft 11 of the electric motor 3 with a key groove or the like, and rotates integrally with the rotary shaft 11 of the electric motor 3. In addition, the rotor 1 is sealed with one axial direction {upper side in FIG. 1 (a)} being in sliding contact with the inner surface of the first side housing 5 and the other axial direction {lower side in FIG. 1 (a)}. The pressure plate 17 is slidably contacted and sealed. Further, as shown in FIG. 1B, the rotor 1 is formed with vane grooves 14 that hold the vanes 2 slidably in the radial direction at equal intervals in the circumferential direction.

  The plurality of vanes 2 are partition members having a substantially rectangular shape that divide the pump chamber 13 into a plurality of parts, are slidably supported in the vane grooves 14, and protrude in the radial direction by centrifugal force. The direction outer edge is in sliding contact with the cam surface 12. Thus, when the vane 2 is rotationally driven by the rotor 1, the space volume defined by the vane 2 is directed from one end side to the other end side (rotation direction side) of the pump chamber 13 having a substantially crescent shape. Increase → Decrease.

On the other hand, the housing is formed with a suction passage 15 that guides air to one end side of the pump chamber 13 (a space volume increase start portion).
Further, the housing is formed with a discharge passage 16 that guides pressurized air from the other end side of the pump chamber 13 (the end portion of the decrease in the space volume) to the outside.
As a result, when the electric motor 3 is energized and the rotating shaft 11 of the electric motor 3 rotates, the space volume defined by the vanes 2 increases → decreases. As the space volume partitioned by the vanes 2 increases, the space volume becomes negative pressure and air is sucked into the space volume from the suction passage 15. Subsequently, the space volume partitioned by the vanes 2 is reduced, so that the space volume is pressurized and the compressed air is discharged from the discharge passage 16 to the outside.

Next, the side seal structure that is a feature of the first embodiment will be described.
In the vane pump, one end side (upstream half) of the pump chamber 13 becomes negative pressure, and the other end side (downstream half) of the pump chamber 13 is pressurized. For this reason, when the pressurized air flows from the side (axial direction side) of the rotor 1 to the negative pressure side, the pump efficiency is lowered. Therefore, the vane pump according to the first embodiment employs the following technique as means for preventing air pressurized from the side (axial direction) of the rotor 1 from flowing to the negative pressure side.

The vane pump includes a pressure plate 17 that is disposed between the rotor 1 and the second side housing 6, is fitted to the cam surface 12 (inner wall surface) of the ring housing 4, and is slidably supported in the axial direction. .
A biasing means 18 for biasing the pressure plate 17 toward the rotor 1 side is provided.
A pressurized fluid applying means 20 is provided for guiding the discharged air to a cancellation chamber 19 formed between the pressure plate 17 and the second side housing 6.

  The pressure plate 17 is a plate material that substantially coincides with the cam surface 12, and is fitted to the cam surface 12 and supported so as to be slidable in the axial direction as described above. The sliding clearance between the pressure plate 17 and the cam surface 12 is set to be small so as to prevent seal leakage through the sliding clearance. The pressure plate 17 is, for example, a metal plate having a smooth sliding surface {upper surface in FIG. 1 (a)} of the rotor 1 and the vane 2, and an end portion of the rotating shaft 11 of the rotor 1 is rotatably inserted in a substantially central portion. A recessed portion is formed.

The biasing means 18 is a ring-shaped disc spring that is compressed between the second side housing 6 and the pressure plate 17, and presses the pressure plate 17 toward the rotor 1 by a restoring force. As a result, both sides of the rotor 1 and each vane 2 are sandwiched between the first side housing 5 and the pressure plate 17 and sealed.
The disc spring is an example for explaining the embodiment, and other springs or elastic members such as rubber may be used.
The pressurized fluid applying means 20 is a communication part that communicates the discharge passage 16 formed in the housing and the cancel chamber 19 formed between the pressure plate 17 and the second side housing 6.

(Effect of Example 1)
In the vane pump of the first embodiment, as described above, the pressure plate 17 is pressed against the rotor 1 side by the urging means 18 to seal both sides of the rotor 1 and the vane 2 and the compressed air discharged from the vane pump is supplied. A configuration is adopted in which the gas is guided to a cancel chamber 19 formed between the pressure plate 17 and the second side housing 6.
Here, due to the pressure pressurized on the other end side in the pump chamber 13, a force (force directed outward in the side direction) is generated on the pressure plate 17 away from the rotor 1.
On the other hand, in the vane pump of the first embodiment, the high-pressure discharge air guided to the cancellation chamber 19 between the pressure plate 17 and the second side housing 6 presses the pressure plate 17 toward the rotor 1 (inward in the side direction). Power).
As a result, the outward force in the side direction is canceled by the inward force in the side direction.

For this reason, even if a high pressure acts on the discharge side in the pump chamber 13, there is no need to increase the urging force of the urging means 18 that urges the pressure plate 17 that performs side sealing toward the rotor 1, and The urging force of the means 18 can be reduced to ensure the sealing performance of the side surface of the rotor 1.
Thus, even if a high pressure acts on the discharge side in the pump chamber 13, it is not necessary to increase the urging force of the urging means 18, so that the friction of the rotor 1 can be suppressed and the rotation loss of the rotor 1 is reduced. Can be reduced. That is, the pump efficiency of the vane pump can be increased as compared with the conventional one.
Further, since the rotation loss of the rotor 1 can be reduced, the driving force of the rotor 1 can be reduced, the electric motor 3 for rotating the rotor 1 can be reduced in size, and the physique of the vane pump can be reduced. Moreover, the cost of the vane pump can be reduced by downsizing the electric motor 3.
Furthermore, since the driving force of the rotor 1 can be reduced, the power consumption of the electric motor 3 can be suppressed.

A second embodiment will be described with reference to FIG. In the following embodiments, the same reference numerals as those in the first embodiment denote the same functional objects.
In the first embodiment, a technique for reducing the rotation loss of the rotor 1 by guiding high-pressure discharge air to the cancel chamber 19 and canceling the outward force in the side direction by the inward force in the side direction is shown. It was.
On the other hand, in the second embodiment, it is possible to reduce the rotation loss of the rotor 1 by adopting the following technique.

In the vane pump, as shown in the first embodiment, the intake negative pressure is generated in the increased portion of the space volume partitioned by the vane 2.
The vane pump covers one axial side surface of the pump chamber 13 {the surface on the second side housing 6 side: the lower surface in FIG. 2A} and is sandwiched between the rotor 1 and the second side housing 6. A flexible film-like member 21 that is arranged and drawn to the pump chamber 13 side by negative suction pressure is provided.
The membrane member 21 is disposed in a minute clearance between the rotor 1 and each vane 2 and the second side housing 6.
The membrane member 21 is sandwiched and fixed between the ring housing 4 and the second side housing 6 in the axial direction.
The film-like member 21 in Example 2 is a flexible film having excellent wear resistance and low sliding resistance, such as a polyester resin film or a tetrafluoroethylene resin film. As shown in FIG. 3, the ring housing 4 and the second side housing 6 are sandwiched and fixed.

(Effect of Example 2)
In the vane pump of the second embodiment, when the rotor 1 rotates, an intake negative pressure is generated in an increased portion of the space volume defined by the vane 2. Then, the membranous member 21 sandwiched between the ring housing 4 and the second side housing 6 is drawn toward the pump chamber 13 by the suction negative pressure, and the side surface of the rotor 1 is sealed.
Thus, the sealing performance of the side surfaces of the rotor 1 and the vane 2 is ensured by the film-like member 21 drawn to the pump chamber 13 side. That is, the sealing performance of the side surface of the rotor 1 is ensured without being affected by the discharge pressure of the rotor 1.

As described above, the vane pump according to the second embodiment does not include an urging unit that strongly presses the seal member against the rotor 1 on the discharge pressure side. Therefore, friction of the rotor 1 can be suppressed and rotation loss of the rotor 1 can be reduced. . That is, the pump efficiency of the vane pump can be increased as compared with the conventional one.
Moreover, since the rotation loss of the rotor 1 can be reduced as in the first embodiment, the driving force of the rotor 1 can be reduced, the electric motor 3 for driving the rotor 1 to rotate can be reduced in size, and the physique of the vane pump. Can be reduced. Moreover, the cost of the vane pump can be reduced by downsizing the electric motor 3.
Furthermore, since the driving force of the rotor 1 can be reduced, the power consumption of the electric motor 3 can be suppressed.

On the other hand, in the second embodiment, as described above, since the film-like member 21 is disposed in the minute clearance between the rotor 1 and the second side housing 6, the film-like member 21 is disposed on the discharge side of the pump chamber 13. Even if it moves to the side away from 1, the gap between the membrane member 21 and the rotor 1 is small, and the sealing performance on the side surfaces of the rotor 1 and the vane 2 can be kept high.
Further, since the film member 21 is sandwiched between the ring housing 4 and the second side housing 6 in the axial direction, the film member 21 seals between the ring housing 4 and the second side housing 6. Can also be secured.

(Modification of Example 2)
The vane pump of the second embodiment shows an example in which the pressurized high-pressure air is not guided to the clearance between the membrane-like member 21 and the second side housing 6, but the pressurized high-pressure air in the pump chamber 13 is filmed. The pressurized fluid applying means may be provided so as to guide to the clearance between the shaped member 21 and the second side housing 6.
In this way, by introducing the high-pressure air to the clearance between the membrane member 21 and the second side housing 6, the discharge side (the reduced portion of the space volume defined by the vane 2: the other end side of the pump chamber 13). In this case, the action of separating the film-like member 21 from the rotor 1 is suppressed, and the sealing performance of the side surfaces of the rotor 1 and the vane 2 can be improved.

A third embodiment will be described with reference to FIG.
In the second embodiment, the example in which the film-like member 21 is sandwiched and fixed between the axial directions of the ring housing 4 and the second side housing 6 has been described.
On the other hand, the film-like member 21 of the third embodiment is a hard member (for example, a thin stainless steel plate) having a shape obtained by thinning the pressure plate 17 shown in the first embodiment. That is, the film-like member 21 of the third embodiment is a thin plate material that substantially coincides with the cam surface 12 and is fitted to the cam surface 12 and supported so as to be slidable in the axial direction.
Even in the case of the film-like member 21 that is fitted to the cam surface 12 and supported so as to be slidable in the axial direction as in the third embodiment, the same operational effects as in the second embodiment can be obtained.

[Modification]
In the above-described embodiment, an example in which the present invention is applied to the vane pump used to check the leakage of evaporated fuel in the canister or to feed the evaporated fuel held in the canister to the intake pipe when the intake negative pressure is low is shown. The present invention may be applied to a vane pump used for other purposes.
In the above embodiment, an example in which the present invention is applied to a vane pump that sucks and discharges air has been shown. It may be applied.
In the above embodiment, the example in which the present invention is applied to the vane pump has been described. However, the present invention may be applied to all pump devices including a rotor that rotates in the housing.

It is sectional drawing in alignment with the axial direction of a vane pump, and sectional drawing which looked at the vane pump from the axial direction (Example 1). It is sectional drawing in alignment with the axial direction of a vane pump, and principal part sectional drawing of a vane pump (Example 2). (Example 3) which is sectional drawing in alignment with the axial direction of a vane pump. It is sectional drawing in alignment with the axial direction of a vane pump, and sectional drawing which looked at the vane pump from the axial direction (conventional example).

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Rotor 2 Vane 3 Electric motor 4 Ring housing 5 1st side housing 6 2nd side housing 12 Cam surface (inner wall surface of ring housing)
13 Pump chamber 16 Discharge passage 17 Pressure plate 18 Biasing means 19 Cancel chamber 20 Pressurized fluid applying means 21 Film member

Claims (6)

A rotating rotor;
A ring housing covering the radial direction of the rotor, a housing including a side housing covering the rotation axis direction of the rotor, and a housing provided with a discharge passage for guiding pressurized fluid between the rotor and the ring housing to the outside;
A pressure plate that is disposed between the rotor and the side housing and is fitted to an inner wall surface of the ring housing and is slidably supported in the axial direction;
A biasing means for biasing the pressure plate toward the rotor;
A pressurized fluid applying means for guiding the pressurized fluid to a cancellation chamber formed between the pressure plate and the side housing;
A pressurized fluid ejection device comprising: The pressurized fluid ejection device according to claim 1,
The pressurized fluid discharge device is a pump device that sucks and discharges fluid by a volume change accompanying rotation of the rotor. A rotating rotor;
A ring housing covering the radial direction of the rotor, a side housing covering the rotational axis direction of the rotor, and a housing in which a suction negative pressure is generated in a pump chamber surrounded by the rotor and the ring housing;
A flexible membrane-like member that covers one axial side surface of the pump chamber, is disposed between the rotor and the side housing, and is drawn to the pump chamber side by the suction negative pressure;
A pump device comprising: The pump device according to claim 3,
The pump apparatus according to claim 1, wherein the membrane member is disposed in a minute clearance between the rotor and the side housing. The pump device according to claim 3 or claim 4,
The pump apparatus according to claim 1, wherein the membrane member is sandwiched and fixed between axial directions of the ring housing and the side housing. In the pump apparatus in any one of Claims 3-5,
The pump device includes a pressurized fluid applying unit that guides pressurized fluid to a clearance between the membrane member and the side housing.

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