JPS6242150Y2 - - Google Patents

Description

[Detailed Description of the Invention] <Industrial Application Field> The present invention relates to a pump, and particularly to a pump having an improved structure of an end cover that is fitted into a housing hole of a pump housing.

<Prior Art> In general, a structure in which the opening of a storage hole of a pump is closed by an end cover as shown in FIGS. 1 and 2 is employed.

In such a closed structure, when the pump is operated under high load, the fluid pressure acting on the left side of the end cover 2 is large, and the end cover 2 is deformed as shown in FIG. A protrusion occurs in the gap l between the end cover 1 and the end cover 2.

When the pump is subsequently switched to a no-load state, the fluid pressure acting on the left side of the end cover 2 decreases, and the end cover 2, which had been significantly deformed up until then, returns to its normal position as shown in Fig. 1, with the result that the O-ring 20 protruding into the gap 1 becomes pinched between the housing 1 and the end cover 2. This pinching phenomenon of the O-ring 20 occurs every time the load state of the pump changes, shortening the life of the O-ring 20 and even causing the O-ring 20 to break, resulting in oil leakage.

<Purpose of the invention> The present invention was made to solve these conventional problems, and its purpose is to prevent the elastic deformation of the outer part of the end cover and prevent the O-ring from getting caught. This is to prevent oil leakage due to O-ring damage.

<Structure of the invention> The present invention has been made to achieve the above object, and includes forming an annular thin-walled part in the end cover, and forming a ring-shaped part on the inside of the outer part formed on the outside of the annular thin-walled part. The structural feature is that the inner part is configured to be independently deformable.

<Example> Hereinafter, an example of the present invention will be described based on the drawings. In FIG. 3, reference numeral 1 denotes a housing, and the opening of the housing hole 1a thereof is fluid-tightly closed by an end cover 2 which is secured by a snap spring 3.

A pair of parallel side plates 4 and 5 are fitted in a housing 1 closed by the end cover 2 in a fluid-tight manner, and a cam ring 6 is interposed between the side plates 4 and 5 in a sandwich state. A rotor 7 having a plurality of vanes (not shown) inscribed in the cam ring 6 is interposed between the side plates 4 and 5 located inside the cam ring 6 in a sandwich state. The end cover 2 and the side plate 4 facing it
A pressure chamber 8 is formed in between, and this pressure chamber 8
is communicated with the inside of the cam ring 6 via a discharge port 9a formed in the side plate 4, and is connected to the rotor 7.
The discharge hydraulic pressure generated by the rotation of the body acts on the pressure chamber 8, and a spring 10 is interposed between the end cover 2 and the side plate 4, so that the spring pressure of this spring 10 and the discharge fluid pressure are interposed between the end cover 2 and the side plate 4. Due to the cooperative action of both side plates 4, 5
The cam ring 6 and rotor 7 are clamped between them.

Further, the discharge port 9b formed in the side plate 5 is communicated with a discharge chamber 11 provided in the housing 1, and this discharge chamber 11 is connected to the housing 1.
It communicates with a discharge port 12 provided in the. A suction chamber 13 is formed in the housing 1 facing the outer periphery of the cam ring 6, and this suction chamber 13 is connected to suction ports 14a and 1 formed in the side plates 4 and 5.
It communicates with the inside of the cam ring 6 via 4b.

15 is a pump drive shaft, and this drive shaft 15 is rotatably supported via a metal bearing 17 in a shaft hole 16 formed in the housing 1 so as to coincide with the axis of the rotor 7, and one end of the drive shaft 15 is rotatably supported through a metal bearing 17. It passes through the side plate 5 and is connected to the axis of the rotor 7 by serration.

As shown in FIG. 4, the end cover 2 has an annular thin wall portion 2 that can be elastically deformed in the pump center axis direction.
a is formed at a position closer to the center axis of the pump than the contact point P with the snap spring 3. The end cover 2 is divided into an outer part 2b that is fitted and supported in the storage hole 1a and an inner part 2c by the annular thin wall part 2a, and the inner part 2c is deformed independently with respect to the outer part 2b. configured to be possible. Note that 20 is an O-ring attached to the outer circumferential groove 2e of the end plate 2 to prevent oil leakage from the fitting portion between the end cover 2 and the housing 1.

In the pump that employs the end cover 2 having the above configuration, when the fluid pressure acting on the end cover 2 increases, the inner part 2c is elastically deformed as shown in FIG. Since the elastic deformation of the inner part 2c of the lever is not transmitted, the housing 1 and the end cover 2
It is possible to prevent the gap l between the two from increasing, and the O-ring 20 will not be caught in the gap l.

<Effects of the Invention> As described above, according to the pump of the present invention, an annular thin-walled portion is formed in the end cover, and the end cover is fitted into the storage hole and supported by the outer portion, and the outer portion is Since the end cover is divided into an independently deformable inner part, only the inner part can be elastically deformed in response to the fluid pressure acting on the end cover, and elastic deformation of the outer part can be prevented. This has the advantage that damage caused by the O-ring being pinched can be prevented.

[Brief explanation of the drawing]

1 and 2 are enlarged sectional views of the main parts of the end cover of a conventional pump, FIG. 3 is a sectional view showing the overall configuration of the pump of the present invention, and FIGS. 4 and 5
The figure is an enlarged cross-sectional view of the main parts of the end cover of the pump of the present invention. Explanation of symbols, 1...Housing, 1a...Storage hole, 2...End cover, 2a...Annular thin wall part,
2b...outer part, 2c...inner part, 3...snat spring.

Claims (1)

[Scope of utility model registration request] A pump in which an end cover is fitted into a housing hole of a housing containing pump components such as a rotor and a side plate while being secured by a snap spring, and a pressure chamber is formed between the end cover and the side plate, The end cover is formed with an annular thin wall portion that is elastically deformable in the pump center axis direction at a position closer to the pump center axis than the point of contact with the snap spring, and this annular thin wall portion allows the end cover to fit into the storage hole with an O-ring. A pump characterized in that it is divided into an outer part that is fitted and supported through the outer part, and an inner part that can be deformed independently with respect to the outer part.