JPH029047Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a hydraulic valve gap adjustment device used in a horizontal or inclined position.

A conventional hydraulic valve gap adjustment device includes a cylinder body, a plunger disposed within the cylinder body and having a reservoir chamber inside, a high pressure chamber formed between the closed end of the cylinder body and the plunger, and the plunger. It is located inside a high pressure chamber and consists of a check valve installed on a plunger.

In such a conventional hydraulic valve gap adjustment device, more oil flows from the high pressure chamber through the gap between the cylinder body and the plunger than in the large gap area due to machining accuracy or deviation of the cylinder body or plunger. Because the flow rate is low in the small part, when used horizontally or tilted, air enters the high pressure chamber, and if the small part of the gap between the cylinder body and the plunger is located above, the air that accumulates above the high pressure chamber will flow into the high pressure chamber. There was a problem that the valve gap adjustment function was hindered because the valve did not come out.

This idea was made by focusing on these conventional problems, and includes providing a circumferential groove in the fitting portion of the cylinder body and the plunger, and an axial groove communicating with the circumferential groove from above the high pressure chamber. Accordingly, it is an object of the present invention to provide a hydraulic valve gap adjustment device that can quickly discharge air accumulated above a high pressure chamber to the outside of the high pressure chamber.

This invention will be explained below based on the drawings.

FIG. 1 is a diagram showing an embodiment of this invention. First, the construction will be explained. A cylinder body 1 is inserted into a cylinder head, and the cylinder body is positioned in the circumferential direction by a pin 19.

A plunger 3 and a plunger head 2 are slidably fitted into the inner periphery of the cylinder body, and the open end of the plunger and the open end of the plunger head contact each other to form a reservoir chamber 8 inside. The plunger has a ball 4, a relief spring 5,
A check valve consisting of a retainer 6 is provided, and a high pressure chamber 9 is formed between the plunger and the cylinder body. A return spring 7 is placed between the plunger and the cylinder body under an appropriate set load. The cylinder body is provided with an oil supply annular groove 13 and an oil supply hole 14, and the plunger head is provided with an oil supply annular groove 16 and an oil supply hole 15, through which the oil circuit 12 and the reservoir chamber 8 communicate with each other. is supplied to the reservoir chamber 8. An oil discharge port 18 is provided in a portion of the plunger head near the open end of the cylinder body, and a stopper 17 is attached to the cylinder body at the open end of the cylinder body to prevent the plunger head from slipping out.

A circumferential groove 11 is provided on the inner surface of the cylinder body near the high pressure chamber, and an axial groove 10 is provided on the inner circumference of the cylinder body adjacent to the upper part of the high pressure chamber.
This allows the circumferential groove 11 to communicate with the high pressure chamber 9 .

FIG. 2 shows an example of a device in which the plunger and the plunger head are integrated. In this example, the plunger 3 has a horizontal projection 17a provided on the stopper 17.
and the flat portion 2a of the plunger head 2 cooperating with the flat portion 2a of the plunger head 2. The circumferential groove 11 and the axial groove 10 are provided on the plunger side.

In the example shown in FIG. 3, the sleeve 20 is fitted and fixed to the cylinder body. Before fitting and fixing, the axial groove 10 and the circumferential groove 11 are machined in the sleeve 20 in a manner similar to that shown in FIG.

Next, the effect will be explained. Assuming that the reservoir chamber 8 and the high pressure chamber 9 are filled with oil, when the engine valve opens, the plunger 3 is pushed, and since the check valve is closed at this time, high pressure is generated in the high pressure chamber 9. At this time, the oil in the high pressure chamber 9 slightly leaks to the outside through the gap between the cylinder and the plunger, and the plunger is displaced by that amount.

When the engine valve closes, the plunger 3 is pushed back by the return spring 7, and when the high pressure chamber 9 becomes negative pressure, the check valve opens and the reservoir chamber 8
Oil flows into the high pressure chamber 9. If air enters the reservoir chamber at this time, the air will also enter the high pressure chamber through the check valve, which may impede the normal valve gap adjustment function.

The air entering the high pressure chamber 9 immediately gathers above the high pressure chamber 9. When the engine valve opens and pressure is generated in the high pressure chamber, the air along with oil flows into the axial groove 1.
0, it passes through the circumferential groove 11 and flows to the outside through the gap between the plunger and the cylinder.

According to the present invention, since the upper part of the high pressure chamber and the circumferential groove are communicated through the axial groove, the air accumulated above the high pressure chamber can be quickly discharged to the outside of the high pressure chamber.

[Brief explanation of the drawing]

FIG. 1 is a sectional view of a hydraulic valve gap adjustment device according to the present invention, and FIGS. 2 and 3 are sectional views of another example.
It is a figure similar to the figure. 3... Plunger, 9... High pressure chamber, 10... Axial groove, 11... Circumferential groove.

Claims (1)

[Scope of utility model registration request] A hollow plunger is slidably fitted into the cylinder body, a high pressure chamber is formed between the closed end of the cylinder body and the plunger, and the cylinder body is positioned circumferentially with respect to the cylinder head. A circumferential groove is provided on the inner circumference or the plunger, and the circumferential groove is communicated with the upper part of the high pressure chamber via an axial groove provided in the cylinder body adjacent to the upper part of the high pressure chamber. , Hydraulic valve gap adjustment device used in horizontal or inclined position.