JPH102285A - pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To prevent leakage of a delivery fluid from a connection part between a rear cover and a front body, when a load is applied to a pump and a pressure of the delivery fluid rises. SOLUTION: This pump 1 is constituted by providing a casing 2 formed by connecting a rear cover 4 to a front body 6 and a pump main unit 3 received inside this casing 2 so as to form a high pressure chamber 18 guiding a delivery fluid between the casing 2 and the pump main unit 3. Here, in an internal peripheral surface of either one or both the rear cover 4 appearing in the high pressure chamber 18 and the front body 6, a peripheral groove 23 along a connection part 10 between the rear cover 4 and the front body 6 is provided.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pump suitable for use in a power source such as a power steering device of an automobile.

[0002]

2. Description of the Related Art Conventionally, as a pump of this type, a casing formed by joining a rear cover and a front body is provided in a casing.
In some cases, a pump main body is housed, and a high-pressure chamber is formed between the casing and the pump main body, through which a discharge fluid from the pump main body is guided. In the pump, a seal member is provided at a joint portion between the rear cover and the front body to ensure the hermeticity in the casing. A similar structure is described in JP-A-56-92388.

[0003]

However, in the conventional example, when a load is applied to the actuator into which the discharge fluid discharged from the pump flows, the pressure of the discharge fluid in the high-pressure chamber increases, and the discharge pressure increases. The pressure of the fluid acts on the casing to open the joint between the rear cover and the pump housing. For this reason, the sealing performance of the joint between the rear cover and the front body is reduced, and the discharge fluid may leak from the joint between the rear cover and the front body.

The present invention has been made in view of the above-mentioned circumstances, and an object of the present invention is to prevent leakage of discharge fluid from a joint between a rear cover and a front body during high-speed rotation. It is to provide a pump.

[0005]

SUMMARY OF THE INVENTION Accordingly, the present invention comprises a casing in which a rear cover and a front body are joined, and a pump body accommodated in the casing, wherein a pump is provided between the casing and the pump body. In a pump having a high-pressure chamber into which a discharge fluid is guided, a circumferential groove is provided on an inner peripheral surface of one or both of a rear cover and a front body facing the high-pressure chamber, along a joint between the rear cover and the front body. It has a configuration.

Here, as the pump, various pumps such as a vane pump and a plunger pump can be adopted.

In the above configuration, when a load is applied to the actuator into which the discharge fluid discharged from the pump body flows, and the pressure of the discharge fluid in the high-pressure chamber rises, one of the rear cover and the front body or the front body depends on the pressure of the discharge fluid. The peripheral grooves formed on both inner peripheral surfaces are expanded, and the joint between the rear cover and the front body along the peripheral grooves is brought into close contact.

Therefore, when the pressure of the pump increases, the sealing performance of the joint between the rear cover and the front body is prevented from being reduced, and leakage of the discharge fluid from the joint between the rear cover and the front body can be prevented.

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings as embodiments applied to a vane pump.

FIG. 1 is a sectional view of a pump showing an embodiment of the present invention. In the figure, reference numeral 1 denotes a pump, and the pump 1 accommodates a pump body 3 inside a casing 2.

The casing 2 has a substantially bowl-shaped rear cover 4.
And a front body 6 having an annular recess 5 formed on one side.
Is formed so as to be joined to the peripheral edge portion 6a. A seal ring groove 8 is formed in a peripheral portion 6 a of the front body 6, and a seal ring 9 is mounted in the seal ring groove 8, and a joint 10 between the rear cover 4 and the front body 6 is formed.
Is sealed.

The pump body 3 rotatably accommodates a rotor 12 on which a plurality of vanes 11 are mounted so as to be able to protrude and retract in a substantially radial direction in a cam ring 13. It has a structure sandwiched by. And the cam ring 1
3. Pump chamber 16 between rotor 12 and adjacent vane 11
Is formed. The volume of the pump chamber 16 changes due to the rotation of the rotor 12, 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 cutout passage 17 is formed in the side plate 15 facing the discharge section, the cutout passage 17 being open in the radial direction and communicating with the annular concave portion 5 of the front body 6. , Into the annular concave portion 5 of the front body 6. The pump body 3 is formed to have a diameter smaller than the inner diameter of the rear cover 4. To form a high-pressure chamber 18 into which the discharge fluid is guided.

A drive shaft 19 is attached to the rotor 12 so as to penetrate therethrough. The drive shaft 19 is supported in a through hole 6 b formed in the front body 6 via a bearing member 20. A pulley (not shown) is attached to an end of the drive shaft 19.

The front body 6 has a suction passage (not shown) communicating the pump chamber 16 in the suction section with an oil storage tank (not shown), and a discharge passage 21 communicating with an actuator (not shown) of the power steering device. , This discharge passage 2
A communication path 22 for communicating the pressure chamber 1 with the high-pressure chamber 18 is formed.

A circumferential groove 23 having a wedge-shaped cross section is formed on the inner peripheral surface of the rear cover 4 facing the high-pressure chamber 18.
And the front body 6 along the joint 10.

Reference numeral 24 denotes a seal member for sealing between the drive shaft 19 and the through hole 6b, and reference numeral 25 denotes a seal ring provided between the rear cover 4 and the side plate 14. High pressure chamber 18 and through gap 26
Is divided between

In the pump 1, when the drive shaft 19 is rotated, the rotor 12 of the pump body 3 is driven to rotate. As the rotor 12 rotates, the pump chamber 18 of the pump body 3 expands its capacity in the suction section, and the transfer fluid is sucked into the pump chamber 18 from the oil storage tank (not shown) through the suction passage. When the rotor 12 further rotates, the pump chamber 18 reduces its volume in the discharge section, and the transfer fluid (discharge fluid) is discharged from inside the pump chamber 18. The transfer fluid discharged from the pump chamber 18 is once guided to the high-pressure chamber 18 through the notch passage 17,
The high-pressure chamber 18 flows through the communication passage 22 and the discharge passage 21 and is discharged to an actuator of a power steering device (not shown).

In the pump 1, when a load is applied to the actuator into which the discharge fluid discharged from the pump body 3 flows, and the pressure of the transfer fluid in the high-pressure chamber 18 increases, as shown in FIG. The pressure of the transfer fluid acts on the peripheral groove 23 formed on the inner peripheral surface of the peripheral groove 4 as shown by an arrow P, so that the inside of the peripheral groove 23 is enlarged.
For this reason, the joint 10 between the rear cover 4 and the front body 6 along the circumferential groove 23 is brought into close contact.

Therefore, it is possible to prevent the sealing performance of the joint portion 10 between the rear cover 4 and the front body 6 from deteriorating when the pressure of the pump 1 rises, and to prevent the transfer fluid from leaking from the joint portion 10 between the rear cover 4 and the front body 6. Can be prevented.

Although the embodiment has been described with reference to the drawings, the specific configuration is not limited to this embodiment and can be changed without departing from the spirit of the invention.
For example, the circumferential groove 23 may be formed on the inner peripheral surface of the front body 6 along the joint 10 between the rear cover 4 and the front body 6, or the inner peripheral surface of the rear cover 4 and the inner peripheral surface of the front body 6. It may be formed in both. Although the embodiment in which the pump body 3 is a vane pump has been described, various pumps such as a plunger pump and a piston pump can be adopted as the pump body.

[0021]

As described above in detail, according to the pump of the present invention, it is possible to prevent the sealing performance of the joint between the rear cover and the front body from being lowered when the pressure of the pump body rises, and to prevent the rear cover and the front Leakage of the discharged fluid from the joint of the body can be prevented.

[Brief description of the drawings]

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

FIG. 2 is an enlarged sectional view of a main part of FIG.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pump 2 Casing 3 Pump body 4 Rear cover 6 Front body 10 Joint part 18 High-pressure chamber 23 Peripheral groove

Claims (1)

[Claims] 1. A high-pressure chamber, comprising: a casing formed by joining a rear cover and a front body together; and a pump body accommodated in the casing, wherein a high-pressure chamber into which a discharge fluid is guided is provided between the casing and the pump body. In the formed pump, a peripheral groove is provided on an inner peripheral surface of one or both of the rear cover and the front body facing the high-pressure chamber, along a joint portion between the rear cover and the front body.