JPH02169882A - Sliding support seat type vane pump motor - Google Patents

Abstract

PURPOSE:To reduce the friction power and the leakage rate by pressing a vane coupled with a sliding support seat at its tip to the inner face of a cam ring freely rotatably coupled with a bearing on the outer periphery and bringing both sliding faces into face contact with each other. CONSTITUTION:A cam ring 5 is coupled with a bearing 7 on the outer periphery and made freely rotatably against a housing 6. A vane 3 coupled with a sliding support seat 4 at its tip is pressed to the inner face of the cam ring 5 via the support seat 4. The cam ring 5 and the support seat 4 are brought into wide face contact with each other. In this case, the cam ring 5 is swayed and rotated while kept in face contact with the support seat 4, thus no friction occurs, and the power loss by friction is reduced. The leakage loss can be reduced because of the face contact, and the volume efficiency is improved.

Description

DETAILED DESCRIPTION OF THE INVENTION (a) Field of Industrial Application This invention relates to vane line grooves for vane type hydraulic pumps and hydraulic motors.

(B) Prior Art The vanes of conventional vane pumps and vane motors have a sliding portion that is in line contact with the cam ring.

Since the cam ring is fixed to the housing, the sliding speed is extremely high.

(c) Problems to be Solved by the Invention If the sliding portion is in line contact and the sliding speed is high, it is inevitable that the wear rate will be high. Furthermore, if the cam ring is fixed to the housing, the frictional power associated with sliding is large, which results in loss of power, increases the temperature of the hydraulic oil, and significantly reduces efficiency. Furthermore, with line contact, it is theoretically difficult to keep the leakage rate of hydraulic oil low, and it is difficult to increase volumetric efficiency.

This invention aims to solve these problems.

(d) Means to solve the problem This invention will be explained as follows based on the drawings.

FIG. 1 shows a cross-sectional view of a pump incorporating the mechanism of the invention. When the rotor 2 with the vanes 3 fitted into the grooves on its outer periphery rotates in the direction of the solid arrow at a position eccentric from the rotation center of the cam ring 5, the space surrounded by the cam ring 5, the rotor 2, and the measuring plate 8 is The volume of each room partitioned by the vane 3 changes as the vane 3 rotates, creating a pumping action that sucks hydraulic oil through the suction port 9 and discharges it from the discharge port 10.

As shown in the cross section shown in FIG. 2, the cam ring 5 is in a floating state where it can freely rotate relative to the housing 6 by means of an inner race of a bearing 7 having wide flanges 5a on both sides.

Since the vane 3 rotates while being pressed against the inner surface of the cam ring 5 by centrifugal force during operation, the cam ring 5 also rotates in the same direction. In this case, sliding friction occurs at both contact portions by a distance corresponding to the eccentricity of the rotation center. The distance of friction corresponds to the distance of reciprocating the eccentric distance per rotation of the rotor 2, and is approximately 2 times the inner circumference length of the cam ring 5.
It becomes 0 to 1/30th. Therefore, even during high-speed operation, the relative friction speed between the tip of the vane 3 and the cam ring 5 is very slow. If the relative friction speed of the sliding part is small,
Even if the sliding seat 4 is fitted to the tip of the vane 3 and the contact portion is brought into surface contact, problems associated with friction will not occur. The outer contact portion 4a of the sliding seat 4 is made to have the same radius of curvature as the inner surface of the cam ring 5, and the contact surface 4b with the vane 3 is also made to match the curved surface of the tip of the vane 3. With this design, the contact surfaces 4a and 4b are always in surface contact no matter what position the vane 3 is in during rotation.

(e) If a rotational force is applied to the working rotor T1111 from the outside,
The vane 3 rotates while being pressed against the inner surface of the cam ring 5 by centrifugal force. In this case, the sliding seat 4 rotates while swinging so that surface contact is maintained between the cam ring 5 and the vane 3 in any position, so leakage of hydraulic oil from the contact surface can be minimized. . Since the contact surfaces are in surface contact, the contact stress at the contact portion is reduced, and wear is suppressed to the extent that it hardly becomes a problem. Due to the action of the bearing 7, the cam ring 5 rolls against the housing 6, causing friction, so that the loss of power due to friction is significantly reduced compared to the conventional linear contact type.

(f) Example The vane pump and vane motor basically have the same structure, but in the case of the vane motor, no centrifugal force acts on the vanes 3 at startup, so in order to maintain contact with the cam ring 5, as shown in Figure 4. A spring 11 that pushes out the vane 3 as shown in
It is necessary to provide

During operation, in contrast to the case of a pump, high-pressure oil is supplied from 10 as shown by the dashed arrow, rotates the rotor 2, and is discharged from 9. At this time, the effect of the sliding seat 4 provided at the tip of the vane 3 is exactly the same as in the case of a pump.

g) Effects of the invention The sliding seat 4 can exhibit its effects only when the cam ring 5 is structured to be able to rotate freely due to the bearing 7. When the cam ring 5 is fixed to the housing 6, 1
The habitual resistance increases and the presence of the sliding catch becomes harmful. Surface contact by the sliding seat 4 is clearly effective in reducing internal leakage loss and significantly increasing volumetric efficiency in both pumps and motors. Since the relative frictional speed between the vane 3 and the cam ring 5 via the sliding seat 4 is small, concerns about wear and the like are eliminated, and even if the maximum rotation speed is more than double that of the conventional fixed camry cag type, it is still practical. It was found that there was no effect on the results.

[Brief explanation of the drawing]

Figure 1 is a longitudinal cross-sectional view. FIG. 2 is a sectional view taken along the line A--A in FIG. 1. Figure 3 (a) is an external view of the vane with the sliding seat fitted. (b) is a detailed explanatory diagram of the vane and sliding catch. FIG. 4 is a functional explanatory diagram of the vane of the vane motor. Go, rotor shaft 2. Rotor 3. Vane 4, vane seat 4a, outer contact portion 4b of vane seat, inner contact surface of vane seat 5. Cam ring 5a, cam ring tsuba 6
．． Housing 7. Bearing 8. Side plate 9. Inlet 10. Discharge port 11, spring

Claims (1)

[Claims] (1) A vane fitted with a sliding seat at the tip is crimped onto the inner surface of the cam ring, which has a bearing fitted on its outer periphery so that it can rotate freely relative to the housing, and the sliding contact portion of the two is pressed against the inner surface of the cam ring, which can rotate freely relative to the housing. Vane type hydraulic pump and hydraulic motor that have surface contact through the seat.