JP2006250072A - Vane pump - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a vane pump suppressing deformation of a plane in a pump chamber side of a housing. <P>SOLUTION: This vane pump is provided with a drive shaft; a rotor rotated and driven by the drive shaft; a vane which is provided so as to freely appear in the diametrical direction in a slot provided in the rotor; a cam ring formed to have an annular shape and forming a plurality of pump chambers in the inner peripheral side together with the rotor and the vane; and the housing including a suction port opened in a region where the volume of the plurality of pump chambers is increased and having an arc cross section, a suction passage communicated with the suction port, and a discharge port opened in a region where the volume of the plurality of pump chambers is contracted. In part of the diametrical direction of the suction port, a bridge part connecting the diametrical inside part of the suction port with the outside part is provided. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention relates to a vane pump used for power steering and the like.

As this type of technology, in the vane pump, a cam ring that forms a plurality of pump chambers together with the rotor and the vane makes the pump discharge capacity variable by making the amount of eccentricity with the rotating shaft of the rotor variable. (For example, refer to Patent Document 1).
JP 2003-97453 A

  In the above prior art, a suction passage that is formed inside the housing and penetrates from the radially outer side of the housing to the central portion, and a suction port that communicates with the suction passage are formed. The suction port is formed in a substantially semicircular arc shape so as to cover the pump chamber on the suction side. The suction port is wide in the circumferential direction, narrow in the radial direction, and deep. Low pressure oil acts on the suction port on the pump chamber side surface of the housing radially outside and in the suction passage, but high pressure oil acts on the suction port on the pump chamber side surface of the housing in the radial direction. To do. Further, since low-pressure oil is acting on the suction passage, the housing radially inward of the suction port may not have sufficient strength against the oil pressure. Therefore, there is a step between the radially outer side and the inner side with respect to the suction port on the pump chamber side plane of the housing, and smooth rotation of the rotor and the vane is obstructed, which may cause a reduction in pump efficiency and noise. There was a problem.

  The present invention has been made paying attention to the above problems, and an object of the present invention is to provide a vane pump that suppresses deformation of the pump chamber side plane of the housing.

  In order to achieve the above object, in the present invention, a drive shaft, a rotor driven to rotate by the drive shaft, a vane provided in a slot provided in the rotor so as to be able to protrude and retract in a radial direction, and an annular shape are formed. A cam ring that forms a plurality of pump chambers together with the rotor and vanes on the inner peripheral side, a suction port that opens in a region where the volume of the plurality of pump chambers increases and has an arcuate cross section, and a suction port that communicates with the suction port A vane pump including a passage and a housing including a discharge port that opens to a region where the volume of the plurality of pump chambers is reduced. In a part of the suction port in the circumferential direction, a radially inner portion of the suction port; The bridge part which connects an outer part was provided.

  The vane pump of the present invention includes a bridge portion that connects a radially inner portion and an outer portion of the suction port at a portion in the circumferential direction of the suction port provided in the housing. Therefore, it is possible to suppress a deformation in the pump chamber side plane of the housing from causing a step between the radially inner side and the outer side with respect to the suction port, maintain good pump efficiency, and suppress noise generation.

  Hereinafter, the best mode for realizing the vane pump of the present invention will be described with reference to the drawings.

  First, the structure of the vane pump in a present Example is demonstrated.

  FIG. 1 is a partial sectional view in the axial direction of a variable displacement vane pump 1, and FIG. 2 is a radial sectional view of the vane pump 1.

  The vane pump 1 includes a drive shaft 20 that is rotationally driven by an engine, a rotor 21 that is coupled to the drive shaft 20 so as to rotate together with the drive shaft 20, and a vane 23 that is provided in a slot 22 formed in the rotor 21 so as to be able to project and retract in a radial direction. And a rotor 21 and a vane 23, a cam ring 25 that forms a plurality of pump chambers 24, an adapter ring 26 that houses the cam ring 25, and a pump housing 30 that houses these members. The vane pump 1 is not limited to a variable displacement type and may be a constant displacement type, and is not particularly limited.

  The pump housing 30 includes a front housing 31 and a rear housing 32.

  In the front housing 31, a side plate 50 is accommodated on the bottom side of an accommodation portion 31a that opens in a bottomed cylindrical shape. The rotor 21, the vane 23, the cam ring 25, the adapter ring 26 and the like are accommodated in close contact with the side plate 50. A through hole 31d is formed at the bottom of the housing portion 31a, and the drive shaft 20 is inserted therein.

  The drive shaft 20 is driven to rotate by connecting a driving force input portion 20a at one end of the drive shaft 20 to an output shaft of the engine. The drive shaft 20 is inserted into the insertion hole 32b of the rear housing 32 through the bearing 52, the oil seal 51, the metal bearing 56, the side plate 50, the rotor 21, and the metal bearing 53 in this order from the driving force input portion 20a side. Part 20b is inserted. The drive shaft 20 is rotatably supported via a bearing 52 and metal bearings 53 and 56. The drive shaft 20 and the rotor 21 are spline-coupled, and the rotor 21 rotates together with the drive shaft 20.

  A plurality of slots 22 are formed radially on the rotor 21, and vanes 23 are inserted into the slots 22 so as to be able to project and retract in the radial direction. Pressure oil is supplied to the back pressure chamber 22a at the radially inner end of the slot 22 to press the vane 23 radially outward.

  The cam ring 25 is formed in a substantially circular ring shape, and houses the rotor 21 and the vane 23 therein. The rotor 21 rotates while the inner periphery of the cam ring 25 and the tip of each vane 23 are in sliding contact. Since the cam ring 25 is provided eccentrically with respect to the rotation axis of the rotor 21, the pump chamber 24 formed by the rotor 21, the vane 23 and the cam ring 25 increases and decreases in volume by the rotation of the rotor 21 and performs pump operation. .

  The cam ring 25 is accommodated in an adapter ring 26 formed in a substantially circular ring shape having a larger diameter than the cam ring 25, and the cam ring 25 and the adapter ring 26 are engaged by a pin 27. The cam ring 25 can swing around the pin 27 and can change the amount of eccentricity with respect to the rotation axis of the rotor 21. The capacity of the pump chamber 24 can be changed along with the change in the amount of eccentricity.

  A seal member 28 is provided on the inner peripheral side of the adapter ring 26 and on the substantially opposite side of the position of the pin 27 in the radial direction. The seal member 28 is in close contact with the outer peripheral surface of the cam ring 25 while allowing the cam ring 25 to swing. A space formed by the outer peripheral surface of the cam ring 25 and the inner peripheral surface of the adapter ring 26 is divided into a first fluid pressure chamber 40 and a second fluid pressure chamber 41 by the pin 27 and the seal member 28.

  A through-hole 26a is provided on the second fluid pressure chamber 41 side of the adapter ring 26, and a spring 58 locked to the locking member 57 is inserted on the pump housing 30 side. The spring 58 moves the cam ring 25 through the first fluid. Energize toward the pressure chamber 40 side.

  The discharge hydraulic pressure of the vane pump 1 acts on the first fluid pressure chamber 40 and the second fluid pressure chamber 41. The fluid operating valve 60 supplies pressure oil to the second fluid pressure chamber 41 when the discharge oil pressure is low, and gradually supplies pressure oil to the first fluid pressure chamber 40 side as the discharge oil pressure increases.

  When the discharge pressure rises, the supply of pressure oil to the first fluid pressure chamber 40 increases, and the cam ring 26 is pressed and moves to the second fluid pressure chamber 41 side. When the cam ring 26 moves to the second fluid pressure chamber 41 side, the volume of the pump chamber 24 in the suction stroke decreases, and the volume of the pump chamber 24 in the discharge stroke increases, so that the discharge pressure of the vane pump 1 decreases.

  When the discharge pressure decreases, the supply of pressure oil to the first fluid pressure chamber 40 decreases, and the cam ring 26 is pressed and moves to the first fluid pressure chamber 40 side. When the cam ring 26 moves to the first fluid pressure chamber 40 side, the volume of the pump chamber 24 in the suction stroke increases and the volume of the pump chamber 24 in the discharge stroke decreases, so that the discharge pressure of the vane pump 1 increases.

  With this action, when the rotational speed of the vane pump 1 rises to a certain level, the subsequent discharge pressure is kept constant.

  In the side plate 50, a suction side passage 50a and a discharge port 50b penetrating the side plate 50 are formed. The suction side passage 50a and the discharge port 50b are formed in a substantially semicircular arc shape so as to cover the pump chambers 24 on the suction side and the discharge side. The suction side passage 50 a communicates with a lubricating oil supply passage 31 c formed at the bottom of the housing portion 31 a of the front housing 31 and supplies lubricating oil to the metal bearing 56. The discharge port 50 b communicates with a high pressure chamber 31 b formed at the bottom of the housing portion 31 a of the front housing 31, and the high pressure chamber 31 b communicates with the discharge port 54.

  Further, a back pressure supply path 50c for supplying high pressure oil pressure to the back pressure chamber 22a of the rotor 21 is formed in an arc shape on the side plate 50 so as to cover the back pressure chamber 22a on the suction side and the discharge side, respectively.

  The insertion portion 32 a of the rear housing 32 is inserted into the receiving portion 31 a of the front housing 31 and is in close contact with the rotor 21 and the cam ring 25. In the rear housing 32, a suction port 32c and a discharge side passage 32e are formed in a substantially semicircular arc shape so as to cover the pump chamber on the suction side. The suction port 32 c communicates with the suction port 55 via a suction passage 32 d formed in the rear housing 32. The suction passage 32d communicates with a lubricating oil passage 32j connected to the insertion hole 32b, and the lubricating oil is supplied to the metal bearing 53 through the lubricating oil passage 32j. The discharge-side passage 32e supplies lubricating oil between the pump chamber-side surface 32i that contacts the pump chamber 24 of the rear housing 32 and the rotor 21 and the vane 23 via the lubricating oil passage 32m. The rear housing 32 is formed with a back pressure supply passage 32f for supplying high pressure oil to the back pressure chamber 22a of the rotor 21 in an arc shape so as to cover the back pressure chamber 22a on the suction side and the discharge side, respectively. The rear housing 32 and the side plate 50 described above correspond to a holding member of the present invention.

[Bridge of suction port]
3 is a view showing the structure of the rear housing 32, FIG. 3 (a) is a view seen from the front housing 31 side, FIG. 3 (b) is a cross-sectional view taken along the line AA in FIG. c) is a BB cross-sectional view in FIG.

  A suction port 32c is provided in a circular arc shape so as to cover the pump chamber 24 on the suction side from the pump chamber side surface 32i contacting the pump chamber 24 of the rear housing 32 to the oil suction passage 32d provided in the rear housing 32. ing.

  On the pump chamber side surface 32i of the rear housing 32, low-pressure oil acts in the low-pressure acting surface 32g, the suction passage 32d, and the lubricating oil passage 32j radially outside the suction port 32c. On the other hand, high-pressure oil acts on the high-pressure acting surface 32h on the radially inner side with respect to the suction port 32c. Therefore, the high pressure acting surface 32h is pressed toward the suction passage 32d and the lubricating oil passage 32j, and the front housing 31 side surface of the rear housing 32 is deformed to cause a step between the low pressure acting surface 32g and the high pressure acting surface 32h. May happen. In addition, the suction port 32c and the insertion hole 32b on which the low pressure hydraulic pressure acts respectively have the suction port 32c having a larger area, or the drive shaft 20 falls, causing the high pressure action surface 32h to fall on the suction port side, Deformation may occur in which a step is generated between the low pressure acting surface 32g and the high pressure acting surface 32h. Thereby, since smooth rotation of the rotor 21 and the vane 23 is inhibited, there is a possibility that the efficiency of the pump is reduced or noise is generated.

  Therefore, in the present embodiment, the bridge portion 33 that connects the radially inner side and the outer side of the suction port 32c is provided. 4 is a cross-sectional view of the suction port 32c provided with the bridge portion 33, and the rear housing 32 viewed from the front housing 31 side. As shown in FIG. 4, the bridge portion 33 takes into consideration the reinforcement to the force acting from the high pressure acting surface 32 h toward the suction passage 32 d and the rectifying effect of the oil flow from the suction passage 32 d to the pump chamber 24. The suction port is formed in a flat shape that is narrow in the circumferential direction and deep in the depth direction, that is, in an elongated flat shape toward the direction in which oil is supplied from the suction passage 32d to the pump chamber 24.

  Further, when the tip 33a of the bridge portion 33 is at the same height as the pump chamber side surface 32i of the rear housing 32, the oil flow is stopped by the bridge portion 33, and the rotation of the vane 23 is caused by the shearing force of the oil. Stop it. Therefore, a clearance C is provided between the tip portion 33a and the pump chamber side surface 32i so that oil can flow between the vane 23 and the bridge portion 33.

  According to the configuration of the present embodiment, the bridge portion 33 that connects the inside and the outside in the radial direction of the suction port 32c is provided to increase the strength of the suction port 32c. Therefore, the high pressure acting surface 32h can secure the strength to withstand the pressing force toward the suction passage 32d and the lubricating oil passage 32j. As a result, it is possible to suppress deformation that causes a step between the low pressure acting surface 32g and the high pressure acting surface 32h on the pump chamber side surface 32i of the rear housing 32.

[Effect of Example 1]
(1) A bridge portion 33 that connects the radially inner side and the outer side of the suction port 32c formed in an arc shape is provided to increase the strength of the suction port 32c. Therefore, the high pressure acting surface 32h of the rear housing 32 can secure the strength to withstand the pressing force toward the suction passage 32d and the lubricating oil passage 32j. As a result, it is possible to suppress deformation that causes a step between the low pressure acting surface 32g and the high pressure acting surface 32h on the pump chamber side surface 32i of the rear housing 32. Therefore, since the smooth rotation of the rotor 21 and the vane 23 is hindered, the efficiency of the vane pump 1 and the generation of noise can be reduced (corresponding to claim 1).

  (2) A bridge portion 33 that connects the radially inner side and the outer side of the suction port 32c formed in a substantially semicircular arc shape is provided to increase the strength of the suction port 32c. Therefore, the high pressure acting surface 32h of the rear housing 32 can secure the strength to withstand the pressing force toward the suction passage 32d and the lubricating oil passage 32j. As a result, it is possible to suppress deformation that causes a step between the low pressure acting surface 32g and the high pressure acting surface 32h on the pump chamber side surface 32i of the rear housing 32. Therefore, since the smooth rotation of the rotor 21 and the vane 23 is hindered, the efficiency of the vane pump 1 and the generation of noise can be reduced (corresponding to claim 2).

[Other embodiments]
Although the best mode for carrying out the present invention has been described based on the first embodiment, the specific configuration of the present invention is not limited to each embodiment and does not depart from the gist of the present invention. Any changes in the design of the range are included in the present invention.

  For example, when the rotor 21 of the vane pump 1 rotates clockwise as viewed from the side plate 50 side, the bridge portion 33 may be tilted in the rotation direction of the rotor 21 as shown in FIG. With this shape, oil can be supplied along the rotation direction of the rotor 21, and the efficiency of the vane pump 1 can be increased.

  Further, as shown in FIG. 6, when the suction passage 32d side of the suction port 32c is narrow, the width of the bridge portion 33 on the suction passage 32d side may be reduced in order to secure the flow path area. With this shape, the bridge portion 33 can be provided while ensuring the flow passage area of the suction port 32c.

  Further, as shown in FIG. 7, a plurality of bridge portions 33 may be provided. When a plurality of bridge portions 33 are provided, the respective bridge portions 33 are provided to be inclined along the oil flow path from the suction passage 32d. With this structure, the strength of the rear housing 32 around the suction port 32c can be sufficiently obtained even when the cross-sectional area of the suction port 32c is large.

  Further, as shown in FIGS. 8 and 9, two or three independent suction ports 32c are provided by one or two bridge portions 33 without providing a clearance between the bridge portion 33 and the pump chamber side surface 32i. It is good as one port.

  Further, as shown in FIG. 10, the two bridge portions 33 may be provided in parallel instead of being inclined.

  Further, technical ideas other than the claims that can be grasped from the above embodiments will be described below together with the effects thereof.

(A) In the vane pump according to claim 1 or 2,
The vane pump is characterized in that the bridge portion has a narrow width with respect to the circumferential direction of the suction port and is deep with respect to the depth direction.

  The high pressure acting surface 32h of the rear housing 32 can ensure the strength to withstand the pressing force toward the suction passage 32d and the lubricating oil passage 32j. As a result, it is possible to suppress deformation that causes a step between the low pressure acting surface 32g and the high pressure acting surface 32h on the pump chamber side surface 32i of the rear housing 32. Therefore, since smooth rotation of the rotor 21 and the vane 23 is inhibited, the efficiency reduction and noise generation of the vane pump 1 can be reduced.

  Further, since the oil rectifying effect by the bridge portion 33 can be obtained, the oil can be efficiently supplied to the pump chamber 24.

(B) In the vane pump according to claim 1 or claim 2 or (a) above,
The vane pump is characterized in that a gap is provided between the bridge portion and the vane sliding surface of the housing.

  Due to the gap between the tip of the bridge and the sliding surface of the vane, oil can flow between the vane and the bridge portion, and a reduction in oil suction efficiency can be suppressed.

(C) In the vane pump according to claim 1 or claim 2 or (a),
The vane pump according to claim 1, wherein the suction port side distal end side of the bridge portion is provided so as to be inclined toward the vane moving direction.

  The bridge is inclined along the oil flow from the suction passage inclined toward the traveling direction of the vane to the suction port, so that the oil flow in the suction port is made smoother and the suction efficiency is improved. The decrease can be suppressed.

(D) In the vane pump according to claim 1 or claim 2 or (a) above,
A vane pump, wherein the bridge portion is formed so as to widen from the suction passage side proximal end side toward the suction port side distal end side.

  Even when the flow passage area on the suction passage side of the suction port cannot be secured sufficiently, the width of the suction passage side base end portion of the bridge portion is reduced, so that the flow passage area of the suction port can be secured.

(E) In the vane pump according to claim 1 or claim 2 or (a) above,
A plurality of the bridge portions are provided in the circumferential direction.

  Even when the width of the suction port is large, the strength of the housing around the suction port can be ensured by providing a plurality of bridge portions.

It is an axial direction fragmentary sectional view of a variable capacity type vane pump. It is a variable capacity type vane pump radial direction sectional view. It is a figure which shows the structure of the rear housing which does not provide the bridge | bridging part in the suction port. It is sectional drawing of an inhalation port. It is sectional drawing of the suction port at the time of tilting a bridge part in the rotation direction of a rotor. It is sectional drawing of the suction port at the time of reducing the width | variety by the side of the suction passage of a bridge part. It is sectional drawing of the suction port at the time of providing a some bridge | bridging part. It is sectional drawing of the suction port when not providing a clearance between a bridge | bridging part and the pump chamber side surface. It is a case where no clearance is provided between the bridge portion and the pump chamber side surface, and is a cross-sectional view of the suction port when a plurality of bridge portions are provided. FIG. 6 is a cross-sectional view of the suction port when a clearance is not provided between the bridge portion and the pump chamber side surface and a plurality of bridge portions are provided in parallel.

Explanation of symbols

1 vane pump 20 drive shaft 21 rotor 22 slot 23 vane 24 pump chamber 25 cam ring 28 seal member 30 pump housing 31 front housing 32 rear housing 32c suction port 32d suction passage 32e discharge port 33 bridge portion 40 first fluid pressure chamber 41 second fluid Pressure chamber 50 Side plate

Claims (2)

A drive shaft;
A rotor driven to rotate by the drive shaft;
A vane provided in a slot provided in the rotor so as to freely protrude and retract in a radial direction;
A cam ring which is formed in an annular shape and forms a plurality of pump chambers together with the rotor and vane on the inner peripheral side;
A suction port having an arcuate cross section that opens to a region where the volumes of the plurality of pump chambers increase, a suction passage that communicates with the suction port, and a discharge port that opens to a region where the volumes of the plurality of pump chambers decrease A housing with
Vane pump with
A vane pump having a bridge portion connecting a radially inner portion and an outer portion of the suction port at a part in a circumferential direction of the suction port. A housing;
A drive shaft pivotally supported by the housing;
A rotor provided in the housing and driven to rotate by the drive shaft;
A vane provided in a slot provided in the rotor so as to freely protrude and retract in a radial direction;
A cam ring that is swingably provided in the housing, is formed in an annular shape, and forms a plurality of pump chambers together with the rotor and vanes on the inner peripheral side;
A suction port that is provided on both sides of the cam ring in the axial direction and that opens to at least one side thereof in an area where the volume of the plurality of pump chambers increases; and a discharge port that opens in an area where the volume of the plurality of pump chambers decreases. A holding member comprising:
A seal member provided on the outer peripheral side of the cam ring and separating the outer peripheral side space of the cam ring into a first fluid pressure chamber and a second fluid pressure chamber;
A fluid control valve that swings the cam ring and changes the volumes of the plurality of pump chambers by controlling the pressure of the first fluid pressure chamber or the second fluid pressure chamber;
Vane pump with
A vane pump having a bridge portion connecting a radially inner portion and an outer portion of the suction port at a part in a circumferential direction of the suction port.

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