JPS60206915A - Valve gap automatic corrector - Google Patents

Abstract

PURPOSE:To enhance the reliability in operation of a valve gap automatic adjusting device with a hydraulic lash adjuster by incorporating such a construction that the leak oil from an oil sump as well as a high pressure chamber is returned surely to the oil sump, and by forming an oil return path capable of supplying an optimum amount of oil to the high pressure chamber at all times. CONSTITUTION:In this hydraulic lash adjuster a plunger 12 is fitted in the body 11 consisting of a bottomed hollow cylinder having a closed end at its top, and a resilient member 14 to energize said plunger 12 outward and a check valve 16 to open and close an oil hole 15 in the upper closed end are accommodated in the high pressure chamber 13 formed in the body 11 through said fitting of the plunger 12. Here sealing members 18a, 18b such as O-rings are fitted both in and on the body 11, and right over them circumferential grooves 21a, 21b are formed. The two grooves shall be in mutual communication, while one of them 21a is put in communication to an oil sump 3 formed in a locker arm through a spiral groove 11c provided at the periphery of the body 11 as well as a radially oriented groove 11d provided at the top of the body 11.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to an automatic valve gap correction device for an internal combustion engine, which includes a hydraulic lash adjuster that automatically corrects the valve gap using hydraulic pressure and elastic force of an elastic member.

It is extremely important to reduce the weight of the hydraulic lash adjuster in order to maintain good dynamic characteristics of the valve mechanism, especially when it is incorporated into an overhead cam type internal combustion engine. Efforts have been made to minimize the volumes of the high pressure chamber and oil reservoir chamber that store oil.

However, since oil leaks from the lash adjuster when the engine is stopped, there is a problem that when the engine is restarted, the amount of oil is insufficient and a large amount of air is sucked in, making it impossible for the lash adjuster to function satisfactorily.

The present invention aims to solve this problem.

It is an object of the present invention to provide a new valve gap automatic correction device that can prevent oil shortage by collecting leaked oil into an oil sump chamber when the oil is stopped. An automatic valve gap correction device using a hydraulic lash adjuster with a separate oil sump chamber will be described below with reference to the drawings.

In FIG. 1, the body 11 of the hydraulic lash adjuster 1
is a bottomed hollow cylindrical body having a closed end 11a at the upper part and an open end 1, lb at the lower part, and a plunger 12 is installed inside the hollow cylinder.
It has a portion 12a fitted therein and extending outwardly therefrom. The high pressure chamber 13 is formed between the closed end 11a of the body 11 and the plunger 12, and the elastic body 14 is located within the high pressure chamber 13 to urge the plunger 12 outward from the body 11. . An oil hole 15 for introducing oil from the outside is provided in the body closed end 11a.

Further, a check valve 16 and a check valve cage 17 for controlling the opening and closing of the oil hole 15 are provided in the high pressure chamber.

This hydraulic lash adjuster 1 has a lash adjuster support hole 21 provided in a rocker arm 2 as shown in FIG.
Adjacent to this, an oil reservoir chamber 3 is provided at the back of the upper part. A closed end 11a of the body 11 of the lash adjuster 1 is arranged to face the oil reservoir chamber 3 side. In this configuration, when the engine is stopped, oil in the oil reservoir chamber 3 leaks from the gap 21a between the body 11 and the support hole 21, as shown in FIG. The valve opens again,
When in the stopped state, the force of a valve spring (not shown) is acting on the plunger 12, so that the plunger 12 moves from its stopped position and retracts into the body 11. For that reason! Since the volume inside the E pressure chambers 1 and 3 is reduced, the oil in the chambers leaks from the gap 11c between the inner periphery of the body 11 and the outer periphery of the plunger 12. When the engine is restarted from this state, the plunger 12 will eventually return to the position at which it stopped, but since this oil removal leaks, if the amount of oil in the oil reservoir chamber 3 is insufficient, the oil mixed with air will be transferred to the oil reservoir chamber 3. This leads to suction into the high pressure chamber 13.

As a result, the pores in the high pressure chamber 13 that contain a large amount of air bubbles may suffer from an extreme decrease in rigidity, and may no longer be able to perform the function of normally operating the valve.

The present invention aims to avoid the occurrence of such problems, and in order to prevent the amount of oil from decreasing in the oil sump chamber 3, the oil leaking from the oil sump chamber 3 and the high pressure chamber 13 is reliably drained into the oil sump. Return to chamber 3 to ensure the required amount of oil and always keep ia Ul oil in high pressure chamber 1.
The present invention aims to provide an automatic valve gap correction device having a new structure having an oil return path that can supply oil to the valve. 4 to 11 show embodiments of the present invention. Fourth
Figure (A).

(B) and (C) are provided with sealing materials such as O-rings 18a and 18b on the inner and outer shapes of the body 11, respectively,
In order to prevent oil leakage, circumferential grooves 21a and 21b are provided at positions directly above them, and these circumferential grooves on the inner and outer circumferences are communicated by oil holes, and a spiral groove 11c starting from the circumferential groove on the outer circumference is provided. A groove lid is provided on the top surface of the body.

5(A) and 5(B) show a case where the outer periphery of the body is formed into vertical grooves in the configuration shown in FIG. 4. Figure 6 (A), (B
), for example, the rubber boot 4 is inserted into the rocker arm support hole 21.
It is provided between the lower end 21b of the plunger 12 and the open end 12a of the plunger 12, and the leaked oil is collected here and collected by one or more spiral grooves 11c provided on the outer periphery of the body. A case where this groove is made into a vertical groove is shown in FIGS. 7(A) and 7(B). Also, FIG. 8(A).

(B) is similar to the configuration shown in FIGS. 6 and 7 above, and is provided with a boot 4 for catching oil leakage, and the leaked oil collected here is collected in the oil sump chamber 3 through the support hole 21. This is an example in which the vertical groove 5a is provided in the sleeve 5 that is fitted around the circumference 21a. Figure 9(A).

(I3) is an example in which the groove shape is a spiral groove 5b in the configuration of FIG. 8. In the above example, the boot 4 used can be easily attached to the support hole 21 and the plunger 12 by a method such as baking.

The detailed explanation so far has been based on a configuration in which the hydraulic lash adjuster is arranged adjacent to the oil sump chamber provided in the rocker arm, but depending on the method of use, the sump chamber may be provided separately. The structure may be integrated with the hydraulic lash adjuster.

FIGS. 10(A) and 10(B) show an example of a combined body in which an oil reservoir chamber member 3' provided separately is combined with a hydraulic lash adjuster 1, and in this configuration, as shown in FIGS. 4 to 9 above. The above embodiments can be applied as is. Note that this figure is an example corresponding to FIG. 7. 11(A) and 11(B) show a structure in which the oil reservoir chamber member 3' shown in FIG. 10 is integrated with the hydraulic lash adjuster 1 and the body 11, and in this structure, the oil reservoir chamber member 3' shown in FIG. The embodiment shown in FIG. 9 can be applied as is. Note that this figure is an example corresponding to FIG. 6.

In this way, the present invention provides a means for preventing oil leakage and a means for recovering leaked oil between the body and the plunger, thereby making it possible to secure the required amount of oil. By solving malfunctions in restarting the layer and at the same time making the oil reservoir chamber to the minimum necessary size, it has the great effect of contributing to the weight reduction of the valve train in combination with the rocker arm and hydraulic lash adjuster. I can do it. Incidentally, it has been found that the volume of the oil reservoir chamber of the lash adjuster of the present invention can be reduced to about 1/2 to 273 of the volume of the oil reservoir chamber of a conventional lash adjuster that is accompanied by oil leakage. The second feature of the device configuration is its versatility, which allows it to be widely used in lash adjuster configurations other than those described here (and its industrial effects are extremely large).

[Brief explanation of the drawing]

Figures 1 to 3 are sectional views for explaining the conventional example, and Figures 4 to 1.
FIG. 1 is a sectional view, side view, etc. showing an embodiment of the present invention. The symbols in the drawings indicate the following members, respectively. 1: Body 2: Rocker arm 3: Oil reservoir chamber 4: Boot 5: Sleeve 1'': Body 12: Plunger 13: High pressure chamber 14: Elastic body 15: Oil hole 16: Check valve 17: Check valve cage 18: O-ring 21: Support hole patent applicant 1 forged valve OIFI Co., Ltd.? 2 figures, 3 figures (C) (A) (B) +5 figures (A) (B) Fang figures 6? 8 Figure (A) (B) Figure 5F9 (A) (B)

Claims (1)

[Claims] 1. A bottomed hollow cylindrical body having an oil hole at the bottom;
a plunger that is slidably fitted into the body to form a high pressure chamber between the inner surface of the first bottom portion; and a plunger that is provided within the high pressure chamber to space the plunger toward the open end of the body. A hydraulic lash adjuster is provided, which includes an elastic body for urging, a check valve that is also provided in the high pressure chamber and controls the opening and closing of the oil hole, and a check valve cage that holds the check valve, and the body is connected to the support hole of the rocker arm. In a device in which the outer end of the plunger is supported through an oil reservoir chamber and the outer end of the plunger is brought into contact with the valve head, falling through the gap between the support hole and the outer circumferential surface of the body and the gap between the inner circumferential surface of the body and the plunger. 1. An automatic valve gap correction device characterized in that an oil sealing member is provided, and an oil return path communicating with the oil reservoir chamber is provided in a gap between the support hole and the outer peripheral surface of the body r. 2. A circumferential groove provided on the inner and outer peripheries of the body as an oil return path communicating with the sealing member and the oil reservoir chamber; one or more spiral grooves starting from the circumferential grooves on the outer periphery; An oil hole that communicates the inner and outer circumferential circumferences)1ζ, and a groove at the top of the body that communicates the spiral groove with the oil reservoir chamber, and a position of the body closer to the opening end than the inner and outer circumferential grooves. The automatic valve gap correction device according to claim 1, characterized in that O-rings are provided on the inner and outer peripheries of the valve gap. 3. A circumferential groove provided on the inner and outer peripheries of the body as an oil return path communicating with the sealing member and the oil reservoir chamber, one or more vertical grooves starting from the circumferential hole on the outer periphery; An oil hole that communicates the circumferential grooves on the inner and outer peripheries and a groove on the top of the body that communicates the vertical groove with the oil reservoir chamber are provided, and an inner groove is provided in the body at a position closer to the opening end than the circumferential grooves on the inner and outer peripheries. The automatic valve gap correction device according to claim 1, characterized in that an O-ring is provided on the periphery and the outer periphery. 4. One or more spiral grooves (1η) provided on the outer periphery of the body from the open end to the closed end as an oil return path communicating with the seal member and the oil sump chamber, and communicating the spiral groove with the oil sump chamber. A groove is provided at the top of the body, and a boot-shaped seal member is provided that connects the entire circumference of the opening end of the plunger and the entire circumference of the opening end of the support hole. automatic valve gap correction device. 5. One or more vertical grooves provided on the outer circumferential surface of the body from the open end to the closed end as an oil return path communicating with the sealing member and the oil sump chamber, and the vertical grooves communicate with the oil sump chamber. Claim 1, characterized in that a groove is provided at the top of the body, and a boot-shaped sealing member is provided that connects the entire circumference of the open end of the plunger and the entire circumference of the open end of the support hole. automatic valve gap correction device. 6. A patent characterized in that the body has no grooves on its outer periphery, and a sleeve having one or more longitudinal grooves on its inner periphery over its entire length is fitted between the body and the support hole. An automatic valve gap correction device according to claim 1. 7. The body has no grooves on its outer periphery, and a sleeve having one or more spiral grooves along its entire length on its inner periphery is fitted between the body and the support hole. An automatic valve gap correction device according to claim 1. 8. The valve gap automatic according to claim 1, wherein a combined body is formed by combining the body and an oil reservoir provided separately, and the combined body is fitted into the support hole. correction device. 9. The automatic valve gap correction device according to claim 1, wherein an oil reservoir is formed integrally with the body, and the integrated body and oil reservoir are fitted into the support hole.