JPS6346642Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a hydraulic valve gap adjustment device for an internal combustion engine.

[Conventional technology]

In internal combustion engines, via the Rotzker arm,
There is an end pivot type valve device that opens and closes intake and exhaust valves by transmitting the movement of a cam to the intake and exhaust valves.

In this valve arrangement, the use of fixed pivots to support rocker arms on opposite sides of the intake and exhaust valves requires setting and adjustment of the valve clearance. However, when a hydraulic valve gap adjustment device is used, there is no valve gap, so there is no need to adjust the valve gap during assembly or periodically.

Most hydraulic valve gap adjustment devices are vertical, but in internal combustion engines with horizontal cylinders, the shafts of the intake and exhaust valves and the valve gap adjustment devices are both horizontal.

A conventional horizontal valve gap adjustment device will be explained based on FIG. 1.

A cylinder 2 fixed to a cylinder head 1 of an internal combustion engine has a cylindrical hole-shaped reservoir 3 inside.
The pivot 4, which is formed with a cylindrical shape, and the plunger 5 are slidably fitted with their open ends abutting each other. The pivot 4 is prevented from coming off by a stopper 6 fixed to the open end of the cylinder 2.

The cylindrical portion of the pivot 4 is provided with an oil hole 11 extending outward and outward, leading to the reservoir 3, and annular holes are formed on the outer and inner surfaces of the cylinder 2 at locations corresponding to the oil holes 11. Oil road 7,
8 is provided, and the inner and outer oil passages 7, 8 are connected to the oil hole 9.
It is communicated with.

In this way, the pressure oil supplied to the oil passage 7 is sent into the reservoir 3 through the oil hole 9, oil passage 8, and oil hole 11.

End wall 2 of cylinder 2 and plunger 5
A check ball valve 13 is disposed in a high pressure chamber 12 formed between a and 5a. That is, the ball 16 of the check ball valve 13 is connected to the plunger 5.
The retainer 14 of the check ball valve 13 is in contact with the outer surface of the valve hole 18 at the center of the end wall 5a of the
The coil spring 15, whose one end is pressed against the end wall plate 2a of the cylinder 2, is pressed against the outer surface of the end wall 5a by the elasticity of the coil spring 15.

The ball 16 in the holding cylinder 14 having a small hole (not shown) is pushed into the valve hole 18 by the elasticity of the relief spring 17 housed in the holding cylinder 14.
It is in pressure contact with the

A spherical head 4a formed at the tip of the pivot 4
supports one end of the Rotzker arm 19,
The other end of the arm 19 is in pressure contact with a shaft end (not shown) of an intake/exhaust valve.

The rotation of the cam 21, which is in pressure contact with the rocker arm 19, opens and closes intake and exhaust valves (not shown).

When the pivot 4 is pushed by the load of the intake and exhaust valves, the oil pressure in the high pressure chamber 12 increases, a small amount of oil escapes through the small gap between the cylinder 2 and the plunger 5, and the pivot 4 Only a small amount enters into cylinder 2.

Conversely, when the load on the pivot 4 decreases, the force of the coil spring 15 pushes the plunger 5 and the pivot 4 outward.

At this time, the check ball valve 13 opens and the high pressure chamber 1
The oil corresponding to the reduced oil amount of 2 is transferred to the reservoir 3.
The high pressure chamber 12 is replenished through the valve hole 18.

Most of the oil escaping from the high pressure chamber 12 is returned to the reservoir 3, but some oil leaks to the outside. Oil equivalent to this is supplied from the oil passage 7.

[The problem that the idea attempts to solve]

When replenishing leaked oil as described above, a small amount of air bubbles may be mixed into the oil.

Since air is compressible, if air bubbles in the reservoir 3 enter the high pressure chamber 13, the following problems will occur.

When the load of the valve acts on the pivot 4, the plunger 5 also makes a large reciprocating movement (moves left and right in the figure) together with the pivot 4, and the end of the plunger 5 or the end of the check ball valve 13 touches the end wall of the cylinder 2. 5a, causing an impact noise or adversely affecting the reciprocating action of the intake and exhaust valves, which may cause the valve gap adjustment device to lose its original function.

In particular, in a valve gap adjustment device in which the cylinder 2 is horizontal, the reservoir 3 is long in the horizontal direction but short in the vertical direction, so there is no space for air bubbles in the oil to float up and escape. Air bubbles often enter the high pressure chamber 12 through the check ball valve 13.

The purpose of this invention is to send only the lower oil in the reservoir to the check valve side by placing a ring with a simple structure near the check valve hole in the horizontally arranged plunger. Therefore, it is an object of the present invention to provide a hydraulic valve gap adjustment device that prevents air bubbles from entering a high pressure chamber.

[Means for solving the problems]

In the present invention, a pivot and a plunger each having a cylindrical reservoir inside and having their open ends abutted against each other are loosely engaged in a cylinder facing in the horizontal direction, and at the head of the pivot, In a hydraulic valve gap adjustment device in which the base of the Rocker arm is supported and a check valve for the high pressure chamber formed between the end walls of the plunger and the cylinder is provided in a valve hole provided in the end wall of the plunger, the axis is parallel to the axis of the reservoir and has an upper inner circumference approximately the same height as the upper inner circumference of the valve hole, and near the valve hole,
A ring placed on the lower part of the inner periphery of the reservoir is fitted and suspended, and the ring is provided with a gap that allows the ring to roll on the inner periphery of the reservoir.
The retainer includes a support plate that supports the outer surface of the ring, and a suction hole is formed by the lower peripheral surface of the support plate and the lower inner peripheral surface of the ring.

〔Example〕

Hereinafter, the structure of the present invention will be explained with reference to the embodiments shown in FIGS. 2 to 7.

In FIG. 2, a ring-type suction device 25 is disposed near the through hole 18 for the check valve 13 in the end wall 5a of the plunger 5. As shown in FIG.

This ring type inhaler 25 includes a ring 26,
The ring 26 is composed of a retainer 27 (see FIG. 4) that holds the ring 26, and the upper part of the inner peripheral surface of the ring 26 is approximately at the same height as the upper edge of the valve hole 18.

As shown in FIGS. 3 and 4, the retainer 27 consists of a hollow shaft 28, a mounting flange 29 fixed to one end thereof, and a support plate 31 fixed to the other end. There is.

The hollow shaft 28 has one or more through holes 32.
However, a through hole 33 is formed in the center of each flange 29, and the reservoir 3 and the high pressure chamber 12 communicate with each other.

The ring 26 is fitted and suspended by the hollow shaft 28 , its lower surface abuts the lower inner circumference of the reservoir 3 , and one side thereof is supported by a support plate 31 .

The mounting plate 29 of the retainer 27 is in contact with the end wall 5a of the plunger 5 and is press-fitted into the inner periphery of the reservoir 3.

The lower inner circumferential surface of the ring 26 and the lower outer circumferential surface of the support plate 31 form an upward crescent-shaped suction hole 34 located at the lower part of the reservoir 3, as shown in FIG.

In the device configured in this manner, when the load of the valve train acts intermittently on the pivot 4, the plunger 5 reciprocates slightly in the left and right direction, and the check ball valve 13 opens and closes each time.

When the oil in the reservoir 3 is replenished into the high pressure chamber 12, only the oil in the lower part of the reservoir 3 is
As shown by the arrow 35, air bubbles in the reservoir 3 do not enter the high pressure chamber 12 because they are sucked into the suction hole 34.

From FIG. 5 onwards, another embodiment of the present invention is shown, and members having the same functions as those shown in the first embodiment are given the same reference numerals.

In FIG. 5, the ring 26 is disposed in the reservoir 3 with one side of the ring 26 in contact with the end wall 5a of the plunger 5, and its upper inner peripheral surface is
It is located at approximately the same height as the upper edge of the valve hole 18.

Outer surface of ring 26 (right side in FIG. 5)
is supported by a circular support plate 37 in the retainer 36.

A plurality of bases 37b of locking legs 37a facing in the axial direction of the plunger 5 are integrally provided around the support plate 37, and an outwardly bent piece provided at the free end of the locking legs 37a. 37c is removably locked in an annular groove 38 provided on the inner periphery of the plunger 5.

By forming the retainer 36 as described above and installing it inside the plunger 5, the ring 26
is similar to the device shown in FIG.
can roll on the inner circumferential surface of the

The lower inner circumferential surface of the ring 26 and the lower outer circumferential surface of the support plate 37 of the retainer 36 form an upward crescent-shaped suction hole 34, as shown in FIG. Oil only, arrow 35
As shown in , it can be supplied to the suction hole 34 .

The inhalation hole 34 of the ring-type inhalation device 25 is
3, 5, and 6, it is formed by the lower outer periphery of the support plate 31 or 37 and the lower inner periphery of the ring 26 whose axis is larger than the axis of the support plate 31 or 37. ing. Therefore, the suction hole 34 will necessarily be located at the bottom of the ring-type inhalation device.

The cylinder 2 or plunger 5 of the valve gap adjusting device may rotate little by little due to vibrations during operation of the valve train.

Therefore, even if a bubble prevention valve that simply has a hole at the bottom is installed in the plunger 5, the valve may be removed when the valve gap adjustment device is installed or by the above-mentioned rotation of the cylinder 2 and the plunger 5. There is a risk that the position of the hole may shift from the lowest position.
However, in the ring-type suction device 25 according to the present invention, as described above, the ring 26 can roll on the inner circumferential surface of the reservoir 3, so the suction hole 34 is always formed in the lower part of the reservoir 3, and the suction hole 34 is always formed in the lower part of the reservoir 3.
Air bubbles inside are prevented from entering the high pressure chamber 12.

[Effect of idea]

According to the present invention, a ring-type suction device with a simple structure consisting of a ring and its retainer is placed near the valve hole of the check valve, so that the oil in the reservoir is transferred from the bottom of the reservoir to the high-pressure chamber. to prevent air bubbles from entering the hyperbaric chamber from the reservoir.

[Brief explanation of the drawing]

Fig. 1 is a longitudinal sectional front view showing an example of a conventional hydraulic horizontal valve gap adjustment device, Fig. 2 is a longitudinal sectional front view showing an embodiment of the present invention, and Fig. 3 is A of Fig. 2.
4 is a perspective view of the retainer in FIGS. 2 and 3, FIG. 5 is a vertical sectional front view showing the main parts of another embodiment of the present invention, and FIG.
The figure is a side view similarly seen from the right side, and FIG. 7 is a perspective view of the retainer. 1...Cylinder head, 2...Cylinder,
2a... End wall, 3... Reservoir, 4... Pivot, 5... Plunger, 5a... End wall, 6...
Stopper, 7, 8... Oil passage, 9, 11... Oil hole, 12... High pressure chamber, 13... Check ball valve, 1
4... Holding tube, 15... Coil spring, 16... Ball, 17... Relief spring, 18... Valve hole, 1
9...Rotzker arm, 21...cam, 25...
Ring type suction device, 26... ring, 27... retainer, 28... hollow shaft, 29... flange,
31... Support plate, 32, 33... Through hole, 34...
Suction hole, 35...arrow, 36...retainer, 3
7... Support plate, 37a... Locking leg.

Claims (1)

[Claims for Utility Model Registration] (1) A pivot and a plunger having a cylindrical reservoir inside and having their open ends abutted against each other are loosely engaged in a cylinder facing in the horizontal direction, and A hydraulic valve that supports the base of the rocker arm at the head of the pivot, and has a check valve for the high pressure chamber formed between the plunger and each end wall of the cylinder in a valve hole provided in the end wall of the plunger. In the gap adjustment device, the axis is parallel to the axis of the reservoir,
and has an upper inner periphery that is approximately the same height as the upper inner periphery of the valve hole, and this ring is fitted and suspended in a ring placed on the lower inner periphery of the reservoir near the valve hole; a retainer having a support plate that supports the outer surface of the ring with a gap that allows the ring to roll on the inner circumference of the reservoir, and a lower circumferential surface of the support plate and a lower inner circumferential surface of the ring, A hydraulic valve gap adjustment device for an internal combustion engine, characterized in that a suction hole is formed. (2) A utility model characterized in that the retainer consists of a hollow shaft that fits and supports the ring, a mounting flange provided at one end of the hollow shaft, and a support plate for the ring also provided at the other end. A hydraulic valve gap adjustment device for an internal combustion engine according to registered claim (1). (3) A plurality of locking legs are provided protruding from the periphery of the support plate for the ring, and the tips of the locking legs are provided with a locking groove provided on the inner periphery of the plunger so that the locking legs can be freely engaged and detached. A hydraulic valve gap adjustment device for an internal combustion engine as set forth in claim (2) of the registered utility model, which is provided with a bent piece.