JPH0439431Y2 - - Google Patents

Description

[Detailed explanation of the idea] <Industrial application field> The present invention relates to a vane pump.

<Conventional technology> Conventionally, a vane pump rotatably supports a rotating shaft in a pump housing via a bearing metal, a rotor that holds a vane at one end of the rotating shaft, a seal member at the other end, and a sealing member provided on the inner periphery of the bearing metal. By forming an oil groove on the surface of the pump housing that allows pressure oil from the rotor to leak to the seal member side, and forming a relief passage in the pump housing that allows this leaked pressure oil to escape from the seal member side to the low pressure side, there is a gap between the bearing metal and the rotating shaft. The rotating shaft is lubricated by leaking pressure oil.

<Problem that the invention aims to solve> However, with the above-mentioned configuration, sufficient pressure oil is not generated at low rotation speeds such as when starting the pump, and pressure oil does not leak from the rotor side to the seal side. There is a problem that the bearing metal and rotating shaft cannot be lubricated.

<Means for solving the problem> The present invention has been made to solve the above-mentioned problem, and includes forming an annular oil sump groove approximately in the center of the inner circumferential surface of the bearing metal, and forming an annular oil sump groove in the upper part of the oil sump groove. A communication hole is provided in the pump housing to communicate with the relief passage.

<Function> At low rotations, oil is supplied from the communication hole to the oil sump groove by its own weight, so that the oil stored in this oil sump groove is sent out to the oil groove and returned to the bypass passage via the relief passage. Lubrication is performed between the bearing metal and the rotating shaft.

<Examples> Examples of the present invention will be described below based on the drawings. In FIG. 1, reference numeral 10 denotes a pump housing, and a hollow chamber 11 with a bottom is formed in this pump housing 10, and this hollow chamber 11 is open at one end of the pump housing 10. An end cover 12 that closes the opening of the pump housing 10 is fitted to one end of the pump housing 10, and is prevented from falling off by a snap spring 13. pump housing 10
and an end cover 12.
Inside there is a cam ring 14 and a ring-shaped side plate 15 that is in contact with one side of the cam ring 14.
A disc-shaped side plate 16 that is in contact with the other side of the cam ring 14 is housed therein, and the inner periphery of one side plate 15 is fitted into the central boss portion of the pump housing 10 . A wave washer 1 is installed between the side plate 16 and the end cover 12.
The cam ring 14 and the pair of side plates 15 and 16 are brought into contact with each other by the repulsive force of the wave washer 17. The cam ring 14 and the pair of side plates 15 and 16 are phased by positioning pins supported between the pump housing 10 and the end cover 12.

A substantially elliptical cam surface 20 is formed on the inner periphery of the cam ring 14, and a rotor 22 in which a plurality of vanes 21 that are in sliding contact with the cam surface 20 are fitted so as to be slidable in the radial direction is housed within the cam ring 14. ing. The rotor 22 is splined to one end of a rotating shaft 24, and this rotating shaft 24 is connected to the pump housing 1.
It is rotatably supported by a bearing metal 23 that is fitted into the bearing hole 0, and a spiral oil groove 36 is formed on the inner peripheral surface of the bearing metal 23. An annular oil sump groove 39 is formed approximately in the center.

With the above configuration, the cam surface 2 of the cam ring 14
A plurality of pump chambers partitioned by vanes 21 are formed between the rotor 22 and the outer peripheral surface of the rotor 22, and the volume of each pump chamber changes as the rotor 22 rotates. On each side of the pair of side plates 15, 16 that are in contact with the rotor 22, suction ports 25, 26 are provided corresponding to the pump chambers that perform the expansion process, and discharge ports 2 are provided that correspond to the pump chambers that perform the compression process.
7 and 28 are formed, respectively. The suction ports 25 and 26 are opened to an annular groove 29 recessed in the hollow chamber 11 so as to surround the cam ring 14, and this annular groove 29 communicates with a bypass passage 34 through which pressure fluid is bypassed by a flow rate regulating valve 35. and communicates with the reservoir 32. Bypass path 3
Plug 31 having a curved concave portion at the end of 4
is inserted to form a bent portion that directs the bypass flow toward the outer circumferential surface of the cam ring. An inclined surface that is perpendicular to the flow of the bypass flow is formed at a portion on the outer periphery of the cam ring that faces this bent portion.
The discharge ports 27 and 28 are opened to a discharge chamber 30 formed on the back side of the side plate 15, and this discharge chamber 30 is communicated with a valve hole of a flow rate regulating valve via a passage (not shown). The pump housing 10 also has an oil reservoir 40 and a bypass passage 34 defined by the outer end of the bearing metal 23 and the seal member 18.
A relief passage 37 that communicates with the oil sump groove 39 and a communication hole 38 that communicates from the bypass passage 34 side of the relief passage 37 to the upper part of the oil sump groove 39 are formed.

In the above configuration, when the rotary shaft 24 is driven by the engine, the rotor 22 rotates, thereby causing the working fluid to flow from the suction passage to the suction port 2.
5, 26, and discharge fluid is drawn into the pump chamber via the pump chamber through the discharge ports 27, 26.
28 into a pressure chamber, and from this pressure chamber, it is sent to a power steering device or the like via an unillustrated discharge passage.

Normally, pressure oil leaking from the pump chamber passes through the gap between the rotor 22 and the side plates 15 and 16, the oil groove 36, and the relief passage 37 to the bypass passage 3.
Returned to 4. The rotating shaft 24 and the bearing metal 23 are lubricated by the pressure oil passing through the oil groove 36, and when the engine speed is low, the pressure oil does not leak from the pump chamber, so the oil flows from the communication hole 38 to the oil sump groove 39 due to its own weight. The oil is sent from this oil sump groove 39 to the seal 18 side by the spiral action of the oil groove 36, and is returned to the bypass passage 34 via the relief passage 37, and is Lubrication takes place.

<Effects of the invention> The above configuration has the advantage that the bearing metal and the rotating shaft can be sufficiently lubricated even when the rotational speed of the pump is low.

[Brief explanation of drawings]

FIG. 1 is a sectional view of the vane pump of the present invention. 10... Pump housing, 12... End cover, 14... Cam ring, 15, 16... Side plate, 21... Vane, 22... Rotor,
25, 26...Suction port, 27, 28...Discharge port, 36...Oil groove, 37...Escape passage, 3
8...Communication hole, 39...Oil sump groove.

Claims (1)

[Scope of utility model registration request] A rotor rotatably supports a rotating shaft via a bearing metal of the pump housing, a rotor holds a vane at one end of the rotating shaft, a sealing member is provided at the other end, and the sealing member seals pressure oil of the rotor to the inner peripheral surface of the bearing metal. In a vane pump in which an oil groove is formed to allow side leakage, and a relief passage is formed in the pump housing to allow the leaked pressure oil to escape from the sealing member side to the low pressure side, an annular oil reservoir is provided approximately in the center of the inner circumferential surface of the bearing metal. A vane pump characterized in that a groove is formed in the pump housing, and a communication hole is provided in the pump housing to communicate from the upper part of the oil sump groove to the relief passage.