JP4643301B2 - Vane pump - Google Patents

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 2000-161249 A

  In the above prior art, a suction port is formed as a suction passage that is formed inside the housing and penetrates from the radially outer side to the center of the housing, and a low-pressure concave groove as a suction port that communicates with the suction passage. The 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, according to the present invention, a housing that includes a front housing and a rear housing that is coupled to the front housing and in which an accommodation portion is formed , and a drive shaft that is pivotally supported by the housing are provided. A rotor provided in the housing portion of the housing and driven to rotate by the drive shaft; a vane provided in a slot provided in the rotor so as to be movable in and out in a radial direction; and swinging in the housing portion of the housing A plurality of pump chambers provided on a surface facing the cam ring of the rear housing, and a cam ring formed in an annular shape and forming a plurality of pump chambers together with the rotor and vanes on an inner peripheral side. a suction port which volume is open in the region increases, the discharge side passageway which opens in the area of reducing the volume of the multiple pump chamber, said Li A suction passage provided in the housing, spaced apart in the rotational axis direction of the suction port and the drive shaft, and formed to extend in the radial direction with respect to the rotational shaft; provided on the outer peripheral side of the cam ring; The cam ring is configured to control the pressure of the first fluid pressure chamber or the second fluid pressure chamber by separating the outer peripheral space of the cam ring into a first fluid pressure chamber and a second fluid pressure chamber. At least one of a fluid control valve that changes the volume of the plurality of pump chambers and a starting end or a terminal end of the suction port and the suction passage. It is disposed between the suction port and the suction passage, and is formed between the suction port and the suction passage, and is connected between the suction port and the suction passage. With And the inner peripheral surface oil passage portion is constituted by the overlaid portion of Bei example, said oil passage, so that the circumferential width of the rotation axis is larger than the circumferential width of the suction passage And arranged so as to overlap the suction passage in the direction of the rotation axis .

  In the vane pump of the present invention, between the starting end portion of the suction port and the suction passage, between the built-up portion formed in a convex shape inside, and the built-up portion and the opening surface of the suction port And an oil passage formed. 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 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 working chamber 41 by the pin 27 and the seal member 28.

  A through hole 26a is provided on the second working 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 allows the cam ring 25 to be connected to the first fluid pressure. Energize to the 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.

[Overlaying part]
FIG. 3 is a view showing the structure of the rear housing 32 in which the suction port 32c is formed to taper from the suction passage 32d toward both ends. FIG. 3A is a surface view seen from the front housing 31 side. 3 (b) is a cross-sectional view taken along the line AA in FIG. 3 (a), and FIG. 3 (c) is a cross-sectional view taken along the line BB in FIG. 3 (a).

  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. Further, the suction port 32c and the insertion hole 32b on which the low pressure hydraulic pressure acts respectively have a larger area on the suction port 32c, so that the high pressure action surface 32h is tilted to the suction port side, and the low pressure action surface 32g and the high pressure action surface. There may be a deformation that causes a step between 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 this embodiment, the built-up portion 33 is provided in the suction port 32c. 4A is a cross-sectional view of the suction port 32c provided with the built-up portion 33, and FIG. 4B is a surface view of the rear housing 32 viewed from the front housing 31 side.

  In this embodiment, the rotor 21 and the vane 23 rotate clockwise while sliding on the surface of the rear housing 32 in FIG. The position of the suction port 32c where the pump chamber 24 begins to supply oil by the rotation of the rotor 21 and the vane 23 is defined as a start end portion 32k, and the position of the suction port 32c where the pump chamber 24 finishes supplying oil is defined as a termination portion 32l.

  As shown in FIG. 4, the built-up portion 33 is provided between the start end portion 32k and the end portion 32l of the suction port 32c and the suction passage 32d, and is provided in a convex shape inside the suction port 32c. In such a configuration, the flow area of the oil on the suction passage 32d side is reduced, but the opening area on the pump chamber side surface 32i side of the suction port 32c is secured to cover the suction side pump chamber 24. As a result, a decrease in the amount of oil supplied to the pump chamber 24 can be suppressed. In particular, in the case of the variable displacement vane pump as in the present embodiment, the intake amount decreases as the oil discharge pressure increases, so even if the oil supply amount decreases somewhat, the effect on the efficiency of the vane pump 1 is small.

  According to the configuration of the present embodiment, the built-up portion 33 is provided between the start end portion 32k and the end portion 32l of the suction port 32c and the suction passage 32d, and is provided in a convex shape inside the suction port 32c. Increase strength. 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.

  The build-up portion 33 may be provided only between one of the start end portion 32k and the suction passage 32d or between the end portion 32l and the suction passage 32d. The rotor 21 and the vane 23 move the pump chamber side surface 32i of the rear housing 32 from the start end portion 32k to the end end portion 32l. Accordingly, the oil supply flow path from the suction passage 32d to the pump chamber 24 is in the direction from the suction passage 32d to the end portion 32l. Therefore, as shown in FIG. 5, the build-up portion is provided between the start end portion 32k and the suction passage 32d. When 33 is provided, it is possible to further suppress a reduction in the efficiency of oil suction into the pump chamber 24.

[Effect of Example 1]
(1) The build-up portion 33 is provided between the start end portion 32k of the suction port 32c and the suction passage 32d, and is provided in a convex shape inside the suction port 32c 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 vanes 23 is not inhibited, Ru can be suppressed the occurrence of reduced efficiency and noise of the vane pump 1.

(2) In the suction port 32c formed in a substantially semicircular arc shape, the build-up portion 33 is provided between the start end portion 32k of the suction port 32c and the suction passage 32d and protrudes inside the suction port 32c. It 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 vanes 23 is not inhibited, Ru can be suppressed the occurrence of reduced efficiency and noise of the vane pump 1.

[Other Examples]
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, as shown in FIG. 6, a plurality of steps 33a may be provided between the built-up portion 33, the start end portion 32k, and the end portion 32l. Since the plurality of steps 33a smooth the shape change from the built-up portion 33 to the start end portion 32k and the end end portion 32l, the oil flow in the suction port 32c becomes smooth, and the efficiency of sucking oil into the pump chamber 24 is improved. Can be suppressed.

  Moreover, as shown in FIG. 7, you may provide the taper part 33b which formed between the build-up part 33, the start end part 32k, and the termination | terminus part 32l in the taper shape. The tapered portion 33b makes the shape change from the build-up portion 33 to the start end portion 32k and the end end portion 32l smooth, so that the flow of oil in the suction port 32c becomes smooth, and the efficiency of oil suction into the pump chamber 24 is improved. The decrease can be suppressed.

[Reference example]
In Reference Example 1 shown in FIG. 8, provided with a suction passage 32d on the starting end 32k side it is formed so as to widen toward the suction port 32c to the end portion 32l. The rotor 21 and the vane 23 move the pump chamber side surface 32i of the rear housing 32 from the start end portion 32k to the end end portion 32l. Therefore, the oil supply passage from the suction passage 32d to the pump chamber 24 is in the direction from the suction passage 32d to the end portion 32l. Since the suction port 32c is formed along the oil supply flow path, the flow of oil in the suction port 32c becomes smooth, and a decrease in the efficiency of sucking oil into the pump chamber 24 can be suppressed.

Further, in Reference Example 2 of FIG. 9 , the build-up portion 33 is provided between the suction passage 32d and the start end portion 32k, and the circumferential position between the build-up portion 33 and the suction passage 32d is partially overlapped. It is . With this configuration, it is possible to ensure the strength of the rear housing 32 around the suction port 32c that overlaps the suction passage 32d having a low strength in the circumferential position. It should be noted that the space between the suction passage 32d and the end portion 32l may be tapered as shown in FIG. 9, or may be formed with a plurality of steps as shown in FIG.

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 build-up part. It is sectional drawing of the suction port which provided the build-up part, and the surface view of a rear housing. FIG. 4 is a cross-sectional view of a suction port provided with a built-up portion between a suction passage and a start end, and a surface view of a rear housing. FIG. 6 is a cross-sectional view of a suction port provided with a plurality of steps in the build-up portion, and a surface view of the rear housing. It is sectional drawing of the suction port which made the build-up part tapered, and the surface view of a rear housing. FIG. 4 is a cross-sectional view of a suction port formed by providing a suction passage at the start end and widening the suction port toward the end portion 32l, and a surface view of the rear housing. FIG. 4 is a cross-sectional view of a suction port provided with a built-up portion between a suction passage and a starting end portion so that circumferential positions of the built-up portion and the suction passage partially overlap, and a front view of a rear housing. . FIG. 10 is a cross-sectional view of a suction port provided with a step between the suction passage and the end portion of FIG. 9 and a surface view of a rear housing.

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 operation Chamber 50 Side plate

Claims (1)

A housing including a front housing and a rear housing coupled to the front housing, the housing portion being formed therein ;
A drive shaft pivotally supported by the housing;
Provided within accommodated portion of the housing, a rotor that is rotated 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 with swingably mounted in the accommodated portion of the housing is formed in an annular shape to form a plurality of pump chambers together with the rotor and the vanes on the inner peripheral side,
A suction port provided on a surface of the rear housing facing the cam ring and opening in a region where the volumes of the plurality of pump chambers increase; a discharge side passage opening in a region where the volumes of the plurality of pump chambers decrease;
A suction passage provided in the rear housing, spaced apart in the rotational axis direction of the suction port and the drive shaft, and formed to extend in the radial direction with respect to the rotational shaft;
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 ;
At least one is provided on one, is arranged between the suction passage and the suction port in the rotation axis direction, formed in a convex shape on the inside between the suction passage and the starting end or terminal end of the pre-Symbol intake port The built-up part,
An oil passage that is provided between the suction port and the suction passage, communicates the suction port and the suction passage, and a part of an inner peripheral surface is constituted by the build-up portion ;
With
The oil passage is formed so that a circumferential width around the rotation shaft is larger than a circumferential width of the suction passage, and is arranged so as to overlap the suction passage in the rotation shaft direction. And vane pump.

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