JPH056175U - Vane pump - Google Patents

Abstract

(57) [Abstract] [Purpose] To improve the wear resistance with the plate member that is in sliding contact with the rotation of the rotor. In a vane pump provided with plate members 10 and 17 that are in contact with both ends of a cam ring 6 in the axial direction, a surface 17a of at least one of the plate members 17 that is in contact with the cam ring is shot blasted.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 The present invention relates to a vane pump suitable for application to a hydraulic power source such as an automobile power steering device.

[0002]

[Prior Art]

 As is well known, this type of vane pump accommodates a rotor in which a plurality of vanes are mounted in a cam ring so as to be retractable in the radial direction, and both ends of the opening of the cam ring are closed by plate members. Is configured. Then, by rotationally driving the rotor, the pump chamber formed between the adjacent vanes is expanded and contracted, and the hydraulic oil guided from the suction hole is guided to the discharge hole via the pump chamber. Such a vane pump is disclosed, for example, in JP-A-59-113287.

[0003]

[Problems to be solved by the device]

 The rotor comes into sliding contact with the plate member as it rotates. Generally, the plate material is formed of cast iron, aluminum alloy, or the like having a hardness lower than that of the rotor, so that there is a problem that the sliding contact surface of the plate member, particularly the rotor, is easily worn.

[0004]

[Means for Solving the Problems]

 Therefore, the present invention is directed to a rotor that is rotationally driven by a rotating shaft, a plurality of vanes that are attached to the rotor so as to be retractable in the radial direction, a cam ring that accommodates the rotor to which the vanes are attached, and an axial direction of the cam ring. In a vane pump including plate members that are in contact with both ends, at least one of the plate members has a structure in which a surface of the plate member that is in contact with the cam ring is shot blasted.

[0005]

[Operation] Since the surface of the plate member that is in contact with the cam ring is subjected to shot blasting, the hardness of the processed surface becomes harder, and the processed surface becomes a rough surface, and minute oil pools are formed. When formed, the sliding contact surface is lubricated and wear resistance is improved.

[0006]

【Example】

 An embodiment of the present invention will be described below in detail with reference to the drawings.

FIG. 1 is a sectional view showing the overall structure of a vane pump to which an embodiment of the present invention is applied, and FIG. 2 is a front view of a cover plate.

In the figure, 1 is a housing, 2 is a drive shaft, and 3 and 4 are bearings and bushes which respectively support the drive shaft 2. An annular recess 5 having one end opened is formed in the housing 1, and a cam ring 6 is mounted in the annular recess 5. In the cam ring 6, a rotor 7 fitted to the drive shaft 2 by a spline is housed. A plurality of vanes 8 are attached to the rotor 7 so as to be retractable in the radial direction, and the tips of the vanes 8 are in sliding contact with the inner peripheral cam surface 6 a of the cam ring 6. A pump chamber 9 is formed by the cam ring 6, the rotor 7, and the two adjacent vanes 8. The pump chamber 9 has its volume changed by the rotation of the rotor 7, and a suction section is formed in a portion where the volume increases due to the change, and a discharge section is formed in a portion where the volume decreases.

A side plate 10 is attached to one side surface of the cam ring 6 in the annular recess 5, and the side plate 10 has a discharge port 11 and a discharge port 11 formed to face the discharge section of the pump chamber 9. A discharge passage 12 communicating with the discharge port 11 is provided, and the entire amount of discharge oil is guided to the high pressure chamber 13 via the discharge passage 12.

A flow control valve 15 is provided between a high pressure passage 14 guided from the high pressure chamber 13 and a low pressure passage communicating with a suction hole (not shown). The excess amount of the introduced discharge oil is recirculated to the low pressure passage 16, and the discharge amount discharged to the actuator from a discharge hole (not shown) communicating with the flow rate control valve 15 is controlled to a constant amount.

Reference numeral 17 denotes a rear cover. The rear cover 17 is attached to a housing 1 that accommodates each member such as the cam ring 6 and the rotor 7 by a mounting bolt (not shown), and an opening end of the housing 1 is attached to the outside of the cam ring 6. It is closed along with the sides. As shown in FIG. 2, the rear cover 17 has a suction passage 18 communicating with the low-pressure passage 16, two suction ports 19a and 19b opening toward the suction sections of the left and right pump chambers 9, and these two suction ports 19a and 19b. A branch passage 20 is formed to connect the suction ports 19a and 19b to the suction passage 18, respectively. Further, on the surface 17a of the rear cover 17 that is in contact with the cam ring 6, a concave annular discharge port 21a, 21b and an annular shape that supplies high pressure oil to the base ends of the vane slots provided in the rotor 7 are not formed in the circumferential direction. The groove 22 is formed. Further, the surface 17a of the rear cover 17 that is in contact with the cam ring 6 is shot blasted. Reference numeral 23 is a mounting bolt insertion hole, and the outer shape of the rear cover 17 is the same as that of the housing 1 in the mating surface with the housing 1.

Reference numeral 24 is a pulley connected to the drive shaft 2, 25 is a shaft seal, and 26 is a seal plate for sealing between the housing 1 and the rear cover 17.

According to such a configuration, the rotor 7 is rotationally driven via the pulley 24 and the drive shaft 2, whereby the pump chamber 9 formed between the adjacent vanes 8 expands and contracts, and hydraulic oil is not shown. It is introduced from the suction hole into the pump chamber 9 through the low pressure passage 16, the suction passage 18, the branch passage 20, and the suction ports 19a and 19b, and is further discharged into the high pressure chamber 13 through the discharge port 11 and the discharge passage 12. After that, the hydraulic oil in the high pressure chamber 13 is guided from the high pressure passage 14 to the flow rate control valve 15, and is guided to the discharge hole via the flow rate control valve 15.

Here, both ends of the rotor 7 are in sliding contact with the plate member, that is, the side plate 10 and the rear cover 17, and in particular, the surface 17 a of the rear cover 17 that is in contact with the cam ring 6 is subjected to shot blasting. The hardness of the sliding contact surface is hard, and the processed surface becomes a rough surface and a minute oil pool is formed to lubricate the sliding contact surface. Wearability is improved.

Although the surface 17a of the rear cover 17 on the side in contact with the cam ring 6 has been shot-blasted, the embodiment is not limited to this, and may be applied to the side plate 10 or the side plate 10. It may be applied to both 10 and the rear cover 17. Needless to say, the invention can be applied to various vane pumps as well as the vane pumps shown in the embodiments.

[0016]

[Effect of the device]

 As described in detail above, according to the present invention, in a vane pump including plate members respectively contacting both axial end portions of a cam ring, at least one of the plate members has a shot surface on the side in contact with the cam ring. By performing blasting, the hardness of the machined surface becomes harder, and the machined surface becomes a rough surface, forming a small oil sump and lubricating the sliding contact surface with the rotor. Wearability improves. Therefore, it becomes possible to easily obtain a vane pump having excellent durability, and it is possible to obtain a great effect in practical use.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a vane pump showing an embodiment of the present invention.

FIG. 2 is a front view of a cover plate.

[Explanation of symbols]

 2 Rotating shaft 6 Cam ring 7 Rotor 10 Side plate 17 Rear cover 17a Surface on the side that contacts the cam ring

Claims (1)

Claims for utility model registration 1. A rotor rotatably driven by a rotary shaft, a plurality of vanes mounted on the rotor so as to be retractable in a radial direction, and a cam ring for housing the rotor on which the vanes are mounted. In a vane pump provided with plate members respectively contacting both axial ends of the cam ring,
A vane pump, characterized in that at least one of the plate members has a surface on the side in contact with the cam ring that is shot blasted.