JPH06146821A - Single constitutional hydraulic rush adjuster - Google Patents

Abstract

PURPOSE:To carry out the stable actuation of a rush adjuster by preventing an oil in the reservoir chamber of the rush adjuster used for the valve system mechanism of an engine from leaking outward during the long term stoppage of an engine. CONSTITUTION:A plunger part 3, a plunger cap part 2 and a separater part 14 are made of the same material as one piece seamless member. Since members around a reservoir chamber 15 therefore have no gap among them, an oil in the reservoir chamber 15 can be prevented from leaking outward during the long term stoppage of an engine.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a hydraulic lash adjuster. More specifically, the present invention relates to a hydraulic lash adjuster in which a plunger portion, a plunger cap portion, and a separator portion are formed as a single continuous structure mainly as a measure against oil spill.

Hereinafter, a hydraulic lash adjuster (hereinafter,
In the present specification, the general operation of "hydraulic type" is simply referred to as "rush adjuster"). In general internal combustion engines, it is necessary to provide a valve clearance in consideration of the difference between the expansion of the cylinder head and the expansion of the valve operating mechanism due to heat, but if this valve clearance is not appropriate, noise will be generated during engine operation. Or a loss of horsepower may occur due to blown raw gas. A lash adjuster is known as a means for solving such a problem. The lash adjuster always keeps the valve clearance at almost zero during operation of the valve mechanism, absorbs changes in expansion due to temperature, prevents noise and blowout of raw gas, and realizes stable operation of the valve mechanism. It is a thing.

In the valve operating mechanism, a cam shaft is arranged on the cylinder head, and an OHC type and a cam shaft for directly driving the intake / exhaust valve via a swing arm are provided in the cylinder block, and a push rod and a swing arm are provided. There is an OHV type that drives an intake / exhaust valve via the. Whether the OHC type or the OHV type, when the engine is operating, the lash adjuster and the intake / exhaust valve function integrally according to the rotation of the cam.

When the engine is stopped, the cam comes into contact with the cam surface at an arbitrary position on the upper surface of the lash adjuster directly or indirectly via the swing arm. Therefore, when the cam nose (protruding part of the cam surface) directly or indirectly contacts the upper surface of the lash adjuster, the urging force of the valve spring that urges the intake / exhaust valve to the closed position is relatively large. A pressure force mainly in the axial direction is constantly applied to the entire adjuster. Therefore, if this stopped state continues for a long time, the oil in the high pressure chamber gradually leaks from the gap between the main body of the lash adjuster and the plunger, and finally the high pressure chamber is in the most crushed state, that is, the volume of the high pressure chamber is the smallest. It becomes a state (so-called "bottoming out state").

Thereafter, when the engine is restarted, the volume of the high pressure chamber of the lash adjuster stopped at the cam nose position increases, the high pressure chamber becomes negative pressure, the check ball opens, and oil is sucked from the reservoir to the high pressure chamber. . When the pressure in the high-pressure chamber reaches a predetermined pressure (pressure during normal operation) again, the check valve closes. In this state, the lash adjuster will perform a normal expansion / contraction operation. Acting in this manner, the lash adjuster automatically adjusts to properly fill any gaps and properly seat the valve. As a result, noise generation can be eliminated. However, when the cam nose starts, air is suddenly sucked into the high pressure chamber from the reservoir chamber immediately after the start via the oil passage in the cylinder head, etc., and the high pressure chamber does not maintain rigidity, so-called "sponge state", and the cam It may not follow the displacement and may generate an abnormal noise. Further, when the engine is operating at a high speed, oil containing a large amount of air is easily sucked into the high pressure chamber. Therefore,
It is important to prevent the intake of air into the high pressure chamber. Therefore, in order to prevent oil containing a large amount of air from entering the high pressure chamber through the reservoir chamber, the plunger cap is provided with a separator separately.

[0006]

In the conventional lash adjuster having the above-mentioned function, for example, when the lash adjuster is mounted on the cylinder head, it becomes bottomed when the cam nose is stopped, and the amount of oil in the high pressure chamber is reduced. It is the smallest. In addition, the oil in the reservoir chamber gradually leaks to the outside through the contact surface between the plunger and the plunger cap, that is, the axial mating surface and the sliding surface between the plunger cap and the main body. Further, oil in the reservoir chamber leaks from between the plunger cap and the separator fitted into it, so if the lash adjuster is left stopped for a long time, the oil will escape to the outside of the lash adjuster through the oil inlet. . In this way, the oil level in the reservoir chamber of the lash adjuster may be considerably lowered during a long stoppage.

As a result, when the engine is restarted after being stopped for a long period of time, even if a separator is provided, air is likely to enter the reservoir chamber, and particularly in the lash adjuster that starts from the bottomed state. Air easily enters the high-pressure chamber, which may cause abnormal noise. When the cam nose starts after the oil has leaked from the lash adjuster to the outside as described above, air is rapidly sucked from the reservoir chamber into the high pressure chamber immediately after the start via the oil passage in the cylinder head etc. The rigidity cannot be maintained, so-called “sponge state” occurs, and it is considered that not only the cam displacement cannot be followed but abnormal noise is generated, but also the achievement of the function of adjusting the valve clearance is affected.

In order to solve the above-mentioned problems, for example, in Japanese Utility Model Laid-Open No. 2-14403, a plunger, a plunger cap, and a separator, which are separately configured, are welded to each other at positions where three members come into contact with each other. It is disclosed that they are connected to each other to prevent oil from leaking between the respective members. However, even if this structure is effective in preventing oil from leaking from the reservoir chamber, each member is required as a separate member and the work of welding them all around is required. There was a problem.

As described above, the conventional lash adjuster has poor workability as a countermeasure against oil spills and has many steps,
Therefore, cost reduction was difficult. From the above, the object of the present invention is to solve the above-mentioned problems of the conventional lash adjuster, to be manufactured with a simpler structure and at a lower cost than the conventional one, and to provide a reservoir for the lash adjuster during a long stoppage or the like. By preventing the oil in the room from leaking out from the body of the lash adjuster through the oil inlet, the oil level in the reservoir room is kept as high as possible, especially when restarting from the cam nose. ,
It is an object of the present invention to provide a lash adjuster capable of preventing intake of air into the lash adjuster, particularly, the high pressure chamber and suppressing generation of abnormal noise.

[0010]

In order to achieve the above-mentioned object, the hydraulic lash adjuster of the present invention is held in a cylinder head so that the rotational displacement of a cam can be transferred to an intake / exhaust valve without producing a valve clearance. A hydraulic lash adjuster for transmitting, a cup-shaped main body having an oil introduction port for introducing oil from the outside, a plunger portion axially slidably fitted in the main body, and an upper portion of the plunger portion. And a separator part that is axially slidably fitted in the main body, and a separator part that divides a space defined between the plunger part and the plunger cap part into two spaces communicating with each other. And the plunger portion, the plunger cap portion, and the separator portion are formed of the same material as a continuous, one-piece construction. It is characterized in that there.

Further, the method of manufacturing the hydraulic lash adjuster of the present invention is a hydraulic lash adjuster which is held in a cylinder head and transmits the rotational displacement of the cam to the intake and exhaust valves without producing a valve clearance. A plunger portion which is slidably fitted in a cup-shaped main body having an oil introduction port for introducing oil from the outside,
Two plunger caps, which are arranged above the plungers and are fitted in the main body so as to be slidable in the axial direction, and two spaces, which communicate with each other, between a space defined between the plungers and the plunger caps. In the method for manufacturing a hydraulic lash adjuster, which is composed of a separator portion that is divided into spaces, and in which the plunger portion, the plunger cap portion, and the separator portion are formed as a continuous single piece made of the same material, in the radial direction. Preparing a cylindrical member that is formed and has a partition wall that divides the interior into two spaces, and that has the first and second cylindrical portions sandwiching the partition wall; and providing the partition wall in the separator portion. Molding, and then molding the first cylindrical portion into the plunger cap portion, and forming a chamber between the second cylindrical portion and the main body. And be molded into the plunger section having a perforated partition wall for forming, it is characterized in that it consists of.

Further, the method of manufacturing the hydraulic lash adjuster of the present invention is a hydraulic lash adjuster which is held in the cylinder head and transmits the rotational displacement of the cam to the intake and exhaust valves without producing a valve clearance. A plunger portion which is slidably fitted in a cup-shaped main body having an oil introduction port for introducing oil from the outside,
Two plunger caps, which are arranged above the plungers and are fitted in the main body so as to be slidable in the axial direction, and two spaces, which communicate with each other, between a space defined between the plungers and the plunger caps. In a method for manufacturing a hydraulic lash adjuster, which is composed of a separator portion that is divided into spaces, the plunger portion, the plunger cap portion, and the separator portion are formed as a continuous single piece made of the same material, wherein Providing a cylindrical member having a partition wall for defining a chamber between the main body and the main body, and reducing the diameter of a substantially intermediate portion in the axial direction of the cylindrical member, and forming the reduced diameter portion as a separator portion. At the same time, by forming the separator portion, the cylindrical member is provided with a portion opposite to the partition wall on the same side as the first cylindrical portion and the partition wall. And it is divided into second cylindrical portion,
The first cylindrical portion is formed on the plunger cap portion, and the second cylindrical portion is the plunger portion having a perforated partition wall.

Further, the method of manufacturing the hydraulic lash adjuster of the present invention is a hydraulic lash adjuster which is held in the cylinder head and transmits the rotational displacement of the cam to the intake and exhaust valves without producing a valve clearance. A plunger portion which is slidably fitted in a cup-shaped main body having an oil introduction port for introducing oil from the outside,
Two plunger caps, which are arranged above the plungers and are fitted in the main body so as to be slidable in the axial direction, and two spaces, which communicate with each other, between a space defined between the plungers and the plunger caps. In a method of manufacturing a hydraulic lash adjuster, which is composed of a separator portion divided into spaces, and in which the plunger portion, the plunger cap portion and the separator portion are formed as a continuous single piece made of the same material, on one side. Preparing a cylindrical member that is a single member formed in the plunger cap, reducing the diameter of an approximately middle portion in the axial direction of the cylindrical member inward, and forming the reduced diameter portion as a separator portion; The other side of the cylindrical member is the plunger portion having a perforated partition wall for forming a chamber between the cylindrical member and the main body; It is characterized by comprising.

[0014]

With the above-described structure, the gap between the plunger portion and the plunger cap portion and the gap between the plunger cap portion and the separator portion even when the engine is operating or when the engine is stopped (when left for a long time). It is possible to prevent the oil in the reservoir chamber from leaking to the outside from the oil introduction port of the main body via the.

[0015]

Preferred embodiments of the present invention will be described in detail below with reference to the accompanying drawings. In the drawings, the same parts are designated by the same reference numerals. FIG. 1 is an axial sectional view showing a first embodiment in which the present invention is applied to an end pivot type lash adjuster. Rush adjuster 10
A substantially cylindrical cup-shaped main body that opens upward, that is, the main body 1, a substantially cylindrical plunger portion 3 slidably fitted in the main body 1, and the plunger portion 3 so as to be continuous and seamless. And a plunger cap 2 that fits into the body 1 above the plunger 3.

The plunger cap portion 2 is provided with an oil ejection port 2a at its tip and is held by a cap retainer 4 so as not to come off from the main body 1. The plunger cap portion 2 includes a small-diameter portion 2b provided with an oil ejection port 2a and a large-diameter cylindrical portion 2c continuous with the small-diameter portion 2b.
And consists of.

At a predetermined position of the plunger portion 3, there is a wall portion 3a which partitions the inside of the main body 1 into two spaces and is provided with an orifice 5, and between the wall portion 3a and the bottom portion of the main body 1,
A high pressure chamber 11 is defined. In the high pressure chamber 11, the check ball 6 seated on the orifice 5 and the check ball 6
Retainer spring 8 for urging the valve to seat on orifice 5, check ball 6 and retainer spring 8
And a plunger spring 9 that abuts the retainer 7 against the wall portion 3a and biases the plunger portion 3 toward the plunger cap portion 2 side.

A reservoir chamber 15 is defined between the wall portion 3a of the plunger portion 3 and the plunger cap portion 2 on the side opposite to the high pressure chamber 11. Therefore, the check ball 6 opens and closes the orifice 5 in accordance with the pressure difference between the high pressure chamber 11 and the reservoir chamber 15, so that the reservoir chamber 1 is placed in the high pressure chamber 11.
Introduce a predetermined amount of oil from 5. Plunger cap part 2
A through hole 13 is provided in the large-diameter cylindrical portion 2c fitted in the main body 1. Therefore, oil such as engine oil introduced from the oil passage 29 provided in the cylinder head shown in FIG.
Through the annular groove 12 engraved on the inner peripheral surface of the main body 1,
First, it enters the plunger cap portion 2 and then is introduced into the reservoir chamber 15.

On the inner peripheral portion of the large-diameter cylindrical portion 2c of the plunger cap portion 2, a separator portion 14 is formed continuously with the plunger cap portion 2 without a seam. The separator portion 14 has a truncated cone shape whose diameter is reduced as a whole toward the oil ejection port 2 a, and the oil supplied from the outside introduced into the reservoir chamber 15 through the oil introduction port 1 a and the through hole 13 is supplied. Is quickly oriented to the oil ejection port 2a. Since the separator portion 14 is provided in the plunger cap portion 2, the oil mixed in with a large amount of air introduced into the lash adjuster 10 from the outside does not come into contact with the separator portion 14.
Oriented upward along the outer peripheral shape of the. This prevents oil containing a large amount of air from entering the reservoir chamber 15 defined between the separator portion 14 and the plunger portion 3, and the air containing oil is removed from the high pressure chamber as the lash adjuster 10 operates. I try not to get in.

As can be clearly seen from FIG. 1, the plunger portion 3, the plunger cap portion 2 and the separator portion 1 are provided.
4 is formed as a continuous member (one component). In particular, it is preferable that the three parts are molded as a single part from the same material so that they are seamless. In the first embodiment, since the plunger portion 3, the plunger cap portion 2 and the separator portion 14 are formed as a continuous member (one component), a gap between the plunger portion and the plunger cap portion and the plunger portion are formed. Since there is no gap between the cap portion and the separator portion, it is possible to prevent the oil in the reservoir chamber from leaking to the outside from the oil introduction port of the main body.

FIG. 2 is a sectional view showing a lash adjuster 50 according to the second embodiment of the present invention. Similar to the first embodiment, the plunger portion 3, the plunger cap portion 2 and the separator portion 14 are formed as a continuous member (one component). In particular, it is preferable that the three parts are molded as a single part from the same material so that they are seamless. The difference from the first embodiment is that the conical portion of the separator portion 14 extends axially longer. In the first embodiment, the opening of the separator portion 14 is located at a level almost close to the position of the through hole 13 of the plunger cap portion 2. However, in the second embodiment,
Hole 14a provided at the top of the conical portion of the separator portion 14
Is considerably axially separated from the position of the through hole 13,
That is, it extends to a position close to the oil ejection port 2a. For this reason, the oil that has entered the plunger cap portion 2 from the through hole 13 circulates around the outer periphery of the conical portion of the separator portion 14 before entering the reservoir chamber 15 because the hole 14a of the separator portion 14 is located at a high place. After that, head toward the oil ejection port 2a. Therefore, in the process, the mixed air in the introduced oil is separated from the oil and easily escapes upward. As a result, oil containing little air enters the reservoir chamber 15,
Air can be more effectively prevented from entering the high-pressure chamber 11 while the lash adjuster 50 is operating.

Also in the second embodiment, the plunger portion 3,
Since the plunger cap portion 2 and the separator portion 14 are formed as a continuous member (one component), a gap between the plunger portion and the plunger cap portion and a gap between the plunger cap portion and the separator portion are formed. Since there is no oil, it is possible to prevent the oil in the reservoir chamber from leaking to the outside from the oil introduction port of the main body. Figure 4
FIG. 4 is a sectional view of the lash adjuster 10 of the first embodiment when it is actually incorporated in a cylinder head of an engine. The cylinder head shown in FIG. 4 is a V-type engine, and therefore is inclined. The lash adjuster 10 is shown in FIG. 4 in a “bottomed state” in which the high pressure chamber 11 is most crushed. Further, it goes without saying that the lash adjuster according to another embodiment of the present invention can be incorporated.

As can be clearly seen from FIG. 4, if the oil inlet 1a is at a low position, a considerable amount of oil will leak from the lash adjuster 10 that is tilted and assembled in the cylinder head until the engine starts. It is expected that it will end up. The lash adjuster 10 is fitted in a substantially cylindrical pocket 28 provided in the cylinder head 30. The pocket 28 is provided with an oil passage 29 through which engine oil or the like is introduced. Oil such as engine oil is introduced from the oil introduction port 1a through the oil passage 29. The tip of the plunger cap 2 is in contact with one end of the swing arm 20. A cam 21 rotatably supported by a rotating shaft 23 is rotatably in contact with a surface 20b of the swing arm 20. In FIG. 4, the cam nose 22 of the cam 21 is shown in contact with the surface 20b and stopped. Since the through hole 20a is provided at one end of the swing arm 20 that abuts on the plunger cap portion 2 so as to face the oil jet port 2a, the engine oil that has passed through the lash adjuster 10 penetrates the oil jet port 2a and the oil jet port 2a. The sliding surface between the cam surface and the surface 20b is lubricated through the hole 20a.

The other end of the swing arm 20 is engaged with one end of an intake / exhaust valve 24. The intake / exhaust valve 24 is biased by a valve spring 25 in a direction to close the intake / exhaust port 27. As already mentioned, FIG. 4 shows the cam nose 2
2 shows the state immediately after the lash adjuster 10 is assembled to the cylinder head 30 in a so-called “at the time of stopping the cam nose” in which 2 is in contact with the swing arm 20. In this state, when the engine is started, the lash adjuster 10 rapidly expands and sucks the oil having a high aeration rate from the oil passage 29 through the oil introduction port 1a. If the oil level in the reservoir chamber 15 is particularly low, a large amount of this oil will be introduced. However, in each of the embodiments of the present invention, since the plunger portion 3, the plunger cap portion 2 and the separator portion 14 are formed as a continuous one-piece (one-piece) member, a space between the plunger portion and the plunger cap portion is formed. And the gap between the plunger cap portion and the separator portion are not present, so that the oil in the reservoir chamber can be prevented from leaking to the outside from the oil introduction port 1a of the main body 1 through these gaps. As a result, the oil level in the reservoir chamber 15 is always kept at a high position in combination with the provision of the separator portion 14, so that the reservoir chamber 15 always contains a sufficient amount of oil. Therefore, the air does not enter from the outside, and it is possible to prevent the air from being sucked into the high pressure chamber 11.

The above will be briefly described with reference to FIG. 3 using the oil level 1 in the reservoir chamber 15. FIG. 3 is drawn in a tilted state assuming that the lash adjuster 10 is used in a cylinder head of a V-type engine. However, the inclination angle is exaggerated to some extent. The oil surface 1 in the horizontal direction is at the level of the open end of the hole 14a of the separator portion 14. Since the plunger part 2, the plunger cap part 3 and the separator part 14 are formed as one unit, there is no gap between them and the oil in the reservoir chamber 15 passes through the oil introduction port 1a through these gaps. There is no danger of leaking to the outside through. Conventionally, even in this state, the oil in the reservoir chamber 15 may leak to the outside through the gap between the plunger and the plunger cap and the gap between the separator and the plunger cap. Next, a method of manufacturing the lash adjuster of the third embodiment of the present invention will be described with reference to FIGS.

First, a cylindrical member 100 shown in FIG. 5 having both ends opened and having a single cylindrical portion 102 and a second cylindrical portion 103 is prepared. Inside the cylindrical member 100 and between the first cylindrical portion 102 and the second cylindrical portion 103,
Partition wall 101 for partitioning the inside of the cylindrical member 100 into two spaces
Is provided at a predetermined position in the axial direction. Cylindrical member 100
Is formed by forging or cutting. Subsequently, a hole 14a penetrating in the axial direction in the partition wall 101 is opened and processed into a tapered shape to form a separator portion 14. The state is shown in FIG. After that, the plunger cap part 2,
The plunger portion 3 and the wall portion 3a of the high pressure chamber 11 are formed by drawing. Further, the oil ejection port 2a and the orifice 5 are also formed. This state is shown in FIG. The wall portion 3a extends from the reservoir chamber 15 toward the outside in the axial direction.
It has a tapered conical slope with a slightly reduced diameter. Wall 3
An orifice 5 that communicates with the reservoir chamber 15 and the high-pressure chamber 11 (not shown in FIGS. 5-7) is axially penetrated through a. The orifice 5 includes an annular flange 3b extending axially outward from the wall 3a. A check ball 6 (not shown in FIGS. 5 to 7) located in the high pressure chamber 11 is seated on one end portion of the annular flange 3b in the axial direction according to the pressure difference.

A through hole 13 for introducing oil into the plunger portion 3 and the plunger cap portion 2 is provided by a press or a drill. FIG. 8 shows a state in which the lash adjuster 60 of the third embodiment is incorporated in the cylinder head. Except for the fact that the wall portion 3a is inclined, and the shape of the end portion of the retainer 7 that contacts the wall portion 3a and the length of the retainer spring 8 are different, the lash adjusters 10 and 50 described above are basically the same. There is almost no difference in structure. According to this embodiment, the plunger portion 2, the plunger cap portion 3 and the separator portion 1
Since there is one unit 4, there is no gap between the respective parts, and there is no fear that the oil in the reservoir chamber 15 will leak to the outside through the hole 14a, the through hole 13 and the oil introduction port 1a.

FIGS. 9 and 10 are sectional views of a lash adjuster according to a fourth embodiment of the present invention, which is a method of manufacturing the lash adjuster. Similar to the third embodiment described above, as shown in FIG. 9, first, both ends are opened, and the first cylindrical portion 1
A cylindrical member 110 composed of 12 and the second cylindrical portion 113 is prepared. Inside the cylindrical member 110, the cylindrical member 110
A partition wall 111 that partitions the inside of the container into two spaces is provided at a predetermined position in the axial direction. The cylindrical member 110 is formed by forging or cutting. Unlike the third embodiment, the partition wall 111 is provided near one end of the cylindrical member 110. This is the partition wall 11 in this embodiment.
This is because 1 is molded as the wall portion 3a between the reservoir chamber 15 and the high pressure chamber 11 (not shown in FIGS. 9 and 10).

First, the orifice 5 is opened in the partition wall 111,
After forming the wall portion 3a, the plunger cap portion 2, the plunger portion 3 and the separator portion 14 are formed by forging or the like. In this embodiment, the separator part 1
4 is molded by squeezing (reducing) inward in the radial direction. Therefore, the separator portion 14 has a constricted shape as illustrated. Through hole 1 for introducing oil into the plunger portion 3 and the plunger cap portion 2
3 is provided in the upper neck portion. According to this embodiment,
Since the plunger part 2, the plunger cap part 3 and the separator part 14 are formed as one unit, there is no gap between the parts, so that the oil in the reservoir chamber 15 passes through the hole 14a, the through hole 13 and the oil introduction port 1a. There is no danger of leaking to the outside.

Finally, with reference to FIGS. 11 and 12, a method of manufacturing the lash adjuster showing the fifth embodiment of the present invention will be described. In this embodiment, different from the above-mentioned third and fourth embodiments, the cylindrical member 120 is formed by forging, cutting or the like, and is provided with a plunger cap portion 2 having an oil ejection port 2a at its tip from the beginning. Further, no partition wall is provided in the middle of the inside of the cylindrical member 120. First, the cylindrical member 120 is prepared, and processing such as drawing is applied to the cylindrical member 120 to form the separator portion 14.
And the wall portion 3a of the high pressure chamber 11 (not shown in FIGS. 11 and 12) is molded. In this embodiment, the separator portion 14 is formed by squeezing inward in the radial direction.
Therefore, the separator portion 14 has a constricted shape as illustrated. A through hole 13 for introducing oil into the plunger portion 3 and the plunger cap portion 2 is provided in the upper neck portion.

According to the present embodiment, since the plunger portion 2, the plunger cap portion 3 and the separator portion 14 are formed as one unit, there is no gap between the respective portions, so that the oil in the reservoir chamber 15 is filled with the holes 14a, There is no risk of leakage to the outside through the through hole 13 and the oil introduction port 1a. As is apparent from the above description, the fourth and fifth embodiments have an advantage that it is not necessary to newly drill the hole 14a of the separator portion 14. In each of the embodiments of the present invention, the lash adjuster of the type in which the oil passing through the inside is discharged from the oil ejection port to lubricate the lubricated surface of the cam has been described, but the present invention is applicable to lash adjusters other than such a type. It goes without saying that it can be applied.

[0032]

According to the lash adjuster of the present invention described above, the following effects can be obtained. Plunger part 2, plunger cap part 3 and separator part 14
Since there is only one unit, there is no gap between each part. Therefore, there is no possibility that the oil in the reservoir chamber 15 leaks to the outside of the lash adjuster through the gap. Also, no welding process is required. Therefore, the oil level in the reservoir chamber can always be kept high, and the maximum amount of oil can always be retained in the reservoir chamber. Therefore, it is possible to prevent external air from entering the high-pressure chamber when the engine is started. In particular, in the case of long-term stoppage in the case of being arranged at an inclination, it is possible to leak a considerable amount of oil in the conventional case, which is more effective. For this reason, it is possible to provide a lash adjuster that maintains stable rigidity in the high-pressure chamber and has stable operation.

[Brief description of drawings]

FIG. 1 is a vertical sectional view showing a first embodiment of a lash adjuster of the present invention.

FIG. 2 is a vertical sectional view showing a second embodiment of the lash adjuster of the present invention.

FIG. 3 is a vertical cross-sectional view showing the state of the oil level in the reservoir chamber when the lash adjuster of the first embodiment is arranged so as to be inclined with respect to the cylinder head.

FIG. 4 is a sectional view of the cylinder head shown with the lash adjuster of the first embodiment incorporated.

FIG. 5 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the third embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the third embodiment of the present invention.

FIG. 7 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the third embodiment of the present invention.

FIG. 8 is a longitudinal sectional view showing an assembled state of the lash adjuster of the third embodiment.

FIG. 9 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the fourth embodiment of the present invention.

FIG. 10 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the fourth embodiment of the present invention.

FIG. 11 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the fifth embodiment of the present invention.

FIG. 12 is a cross-sectional view showing the method of manufacturing the plunger cap portion, the plunger portion and the separator portion of the lash adjuster of the fifth embodiment of the present invention.

[Explanation of symbols for main parts]

 1 …………… Main unit 2 …………… Plunger cap 3 …………… Plunger 14 ……… Separator 15 …………… Reservoir chamber 10, 50 …………… Rush adjuster

Claims (4)

[Claims] 1. A hydraulic lash adjuster which is held in a cylinder head and transmits a rotational displacement of a cam to an intake / exhaust valve without producing a valve clearance, and has an oil introduction port for introducing oil from the outside. A cup-shaped main body, a plunger portion fitted in the main body so as to be slidable in the axial direction, and a plunger cap portion arranged above the plunger portion and fitted in the main body so as to be slidable in the axial direction, A separator part that divides a space defined between the plunger part and the plunger cap part into two spaces communicating with each other, and the plunger part, the plunger cap part, and the separator part are made of the same material to form a joint. A hydraulic lash adjuster that is characterized by being formed as a continuous single piece without. 2. A hydraulic lash adjuster held in a cylinder head for transmitting rotational displacement of a cam to an intake / exhaust valve without producing a valve clearance,
A plunger portion axially slidably fitted in a cup-shaped body having an oil introduction port for introducing oil from the outside, and axially slidably fitted in the body disposed above the plunger portion. And a separator part for dividing a space defined between the plunger part and the plunger cap part into two spaces communicating with each other. The plunger part, the plunger cap part, and In the method for manufacturing a hydraulic lash adjuster in which the separator portion is formed as a continuous single piece made of the same material, there is a partition wall formed in the radial direction and partitioning the inside into two spaces, and the partition wall is sandwiched. And preparing a cylindrical member that is a single member including the first and second cylindrical portions, and forming the partition wall into the separator portion, Forming the first cylindrical portion into the plunger cap portion and forming the second cylindrical portion into the plunger portion having a perforated partition wall for defining a chamber between the first cylindrical portion and the main body. And a hydraulic lash adjuster manufacturing method. 3. A hydraulic lash adjuster held in a cylinder head for transmitting rotational displacement of a cam to an intake / exhaust valve without producing a valve clearance,
A plunger portion axially slidably fitted in a cup-shaped body having an oil introduction port for introducing oil from the outside, and axially slidably fitted in the body disposed above the plunger portion. And a separator part for dividing a space defined between the plunger part and the plunger cap part into two spaces communicating with each other. The plunger part, the plunger cap part, and In the method for manufacturing a hydraulic lash adjuster in which the separator portion is formed as a continuous single piece made of the same material, a cylindrical member having a partition wall for defining a chamber between the separator portion and the main body is provided. At the same time as the preparation and the step of reducing the diameter of substantially the intermediate portion of the cylindrical member in the axial direction and forming the reduced diameter portion as the separator portion, A cylindrical portion to divide the cylindrical member into a first cylindrical portion on the side opposite to the partition wall and a second cylindrical portion on the same side portion as the partition wall, and the first cylindrical portion on the plunger cap portion. And forming the second cylindrical portion as the plunger portion having a perforated partition wall, and a manufacturing method of the hydraulic lash adjuster. 4. A hydraulic lash adjuster which is held in a cylinder head and transmits rotational displacement of a cam to an intake / exhaust valve without producing a valve clearance,
A plunger portion axially slidably fitted in a cup-shaped body having an oil introduction port for introducing oil from the outside, and axially slidably fitted in the body disposed above the plunger portion. And a separator part for dividing a space defined between the plunger part and the plunger cap part into two spaces communicating with each other. The plunger part, the plunger cap part, and In the method of manufacturing a hydraulic lash adjuster in which the separator portion is formed of the same material as a continuous one piece structure, a cylindrical member that is one piece formed in the plunger cap portion on one side is prepared, Reducing the diameter of an approximately middle portion of the cylindrical member in the axial direction to the inside, and forming the reduced diameter portion as a separator portion; Method for producing a hydraulic lash adjuster, characterized in that it consists and, to the plunger portion with a perforated partition wall for forming a chamber between the other side of the body of the wood.