JPH0729267Y2 - Vane pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION << Industrial Application Field >> The present invention relates to a vane pump having a flow rate adjusting valve in which the shape of a shoulder portion of a spool valve is improved.

<< Prior Art >> Generally, in a vane pump, a fluid flows into a working chamber between vanes that rotate integrally with a rotor according to the rotation of the rotor, and the fluid is added by the action of the vanes that are in sliding contact with the cam surface of the cam ring. Operates to press and expel.

This type of vane pump has, for example, as shown in FIG. 3, a housing main body 2 pivotally supporting a drive shaft 15 and a rear side plate 3 fixed to the housing main body 2.
A cam ring 5 accommodating the rotor 4 integral with the drive shaft 15 is arranged between them. The front and rear openings of the cam ring 5 are the rear side plate 3 and the front side plate 6.
Are closed by these, and these form the working chamber (not shown) between the vanes 7 adjacent to each other. In this working chamber, oil is made to flow into the working chamber from the suction passage 9 and is pressurized to form a discharge passage 11 via a flow rate adjusting valve 12.

In FIG. 4, the flow rate adjusting valve 12 is arranged on the upper part of the housing body 2 and has a step portion 2b provided in the spool hole 2a and a spool valve 1 slidably arranged in the spool hole 2a. The amount of oil is regulated by means of and the amount of oil within a predetermined amount is discharged to the discharge port 14, and for high-pressure oil exceeding this amount, the spool valve 1 opens the drain port 16 so that the suction lateral passage 13 side (see FIG. 3). ) Is adopted. As shown in FIG. 5, the surface of the spool valve 1 is coated with a hard alumite layer 1c.

<< Problems to be Solved by the Invention >> However, in the flow rate adjusting valve 12 in the above-mentioned conventional vane pump, the chamfered corner portion 2c formed in the step portion 2b of the spool hole 2a and the shoulder portion 1b of the spool valve 1 are provided. The drain start point 1a to be formed has an edge 1d generated when the chamfering is performed. (See FIG. 5) Therefore, when the spool valve 1 slides in the spool hole 2, the chamfered corner portion 2c and the edge 1d are caught. Therefore, the alumite layer 1c applied to the surface of the spool valve 1 is likely to be chipped, and there is a problem that the spool valve 1 and the spool hole 2 are worn.

The present invention has been made in view of such conventional problems, and an object of the present invention is to provide alumite applied to a spool valve even if the spool valve slides in a spool hole. It is an object of the present invention to provide a vane pump provided with a flow rate adjusting valve capable of preventing abnormal wear of a spool valve from being generated without chipping of layers.

<Means for Solving the Problems> To achieve the above object, the present invention has a flow rate adjusting valve disposed in a housing body, is provided inside the flow rate adjusting valve, and has a discharge passage from a pump and a pump. And a plurality of land portions slidably contacting the spool holes are formed, and the land portion on one end side of the land portion defines the discharge passage side and the drain passage side. A vane pump including the spool valve configured as described above, wherein a shoulder portion of the land portion on the one end side facing the discharge passage has an R shape, and a hard alumite layer is formed on the entire outer peripheral surface of the spool valve. It is characterized by being subjected to a surface treatment by.

<Operation> In the flow rate adjusting valve of the vane pump, the shoulder portion of the spool valve arranged in the flow rate adjusting valve has an R shape. Therefore, even if the spool valve slides in the spool hole, at the step provided in the spool hole,
The edge formed on the step does not get caught.

<< Embodiment >> An embodiment of the present invention will be described below with reference to FIGS. 1 and 2. FIG. 1 is a sectional view showing an embodiment of a flow rate adjusting valve in a vane pump according to the present invention.

As shown in FIG. 1, the flow rate adjusting valve 120 is attached to a housing body 20 of a vane pump (not shown). A spool hole 20a into which the spool valve 10 made of aluminum is fitted is formed in the housing body 20. A step portion 20b is provided at the center of the spool hole 20a, and a chamfered corner portion 20c is formed in the step portion 20b. Further, the spool valve 10 is formed with two land portions 21 and 22 in the axial direction, and the land portion 21 on one end side defines a primary pressure chamber 23 communicating with the discharge passage 140 and a drain passage 26. The land portion 22 on the other end side includes a drain passage 26 and the primary pressure chamber 23.
And a secondary pressure chamber 24 for slidingly adjusting the spool valve 10 are defined. The shoulder portion 10b of the spool valve 10 has an R-shape extending from the drain start point 10a to the tip 10e.
The entire outer peripheral surface of the spool valve 10 is surface-treated with a hard alumite layer 10c as shown in FIG. Next, the operation will be described. When the pump rotates at a high speed, the spool valve slides to the right in FIG. 1 and discharges discharge oil (not shown) from the discharge port 140 to the suction side inside the pump. When the hydraulic pressure outside the discharge connector 140a changes from low pressure to high pressure alternately, the spool valve 10 slides left and right in the spool hole 20a according to the change in pressure, and the discharge passage 140
And the drain 26 are appropriately opened to adjust the amount of hydraulic oil. At this time, the spool valve 10 slides smoothly without being caught by the chamfered corner portion 20c formed on the step portion 20b. Therefore, the hard alumite layer 10c applied to the spool valve 10 is not chipped from the spool valve 10, and abnormal wear due to sliding can be prevented.

<Effect of the Invention> As described above, the vane pump according to the present invention has the flow rate adjusting valve disposed in the housing body, is provided inside the flow rate adjusting valve, and has a discharge passage from the pump and a drain to the pump. A spool hole that opens to the passage and a plurality of land portions that are in sliding contact with the spool hole are formed, and the land portion on one end side of the land portion defines the discharge passage side and the drain passage side. And a shoulder portion of the land portion on the one end side facing the discharge passage, and a surface treatment with a hard alumite layer on the entire outer peripheral surface of the spool valve. Has been applied.

Therefore, even if the spool valve slides in the spool hole, the chamfered corner portion formed in the step portion does not get caught at the step portion provided in the spool hole, so that the hard anodized aluminum is not formed. It is possible to prevent the occurrence of abnormal wear due to sliding without chipping of the layer.

[Brief description of drawings]

FIG. 1 is a sectional view showing a flow control valve according to an embodiment of the present invention, FIG. 2 is an enlarged sectional view showing an essential part of the spool valve shown in FIG. 1, and FIG. 3 is a sectional view showing a conventional vane pump. Figure, 4th
FIG. 5 is a sectional view showing a spool valve of a conventional flow rate adjusting valve, and FIG. 5 is an enlarged sectional view of an essential part of the spool valve of FIG. 10 …… Spool valve, 10b …… Shoulder, 10c …… Hard alumite layer, 20 …… Housing body, 20a …… Spool hole, 20b
…… Step, 120 …… Flow control valve.

Claims (1)

[Scope of utility model registration request] 1. A spool hole having a flow rate adjusting valve disposed in a housing body, the spool hole being provided inside the flow rate adjusting valve, wherein a discharge passage from the pump and a drain passage to the pump are opened, and the spool. A vane pump comprising: a plurality of lands that are in sliding contact with a hole; and a spool valve configured to define the discharge passage side and the drain passage side by a land portion on one end side of the lands. A vane pump characterized in that a shoulder portion of the land portion on the one end side facing the discharge passage has an R shape, and the entire outer peripheral surface of the spool valve is surface-treated with a hard alumite layer.