JP2710851B2 - Bucket-type tapet of engine and method of manufacturing the same - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Application Field) The present invention relates to an intake valve or an exhaust valve for transmitting the operation of a cam portion provided on a camshaft constituting a valve operating mechanism of an engine to an intake valve or an exhaust valve. The present invention relates to a bucket type tappet for an engine arranged at an end of an exhaust valve and a method of manufacturing the same.

(Prior Art) In a valve operating mechanism of an engine, when an operation of a cam portion provided on a camshaft is transmitted to an intake valve or an exhaust valve, a cam portion provided on the camshaft and an end of the intake valve or the exhaust valve. And a bucket type tappet incorporating an adjuster portion having an automatic adjustment mechanism for a valve gap in a combustion chamber of an engine is known between them. The bucket type tappet is provided on a camshaft. And a cylindrical portion having an outer peripheral surface with which the cam portion slides and a cylindrical portion having one end engaged with the disk-shaped portion. A guide provided on the cylinder head of the engine with an adjuster portion slidable with respect to the end of the intake valve or the exhaust valve disposed therein. And is reciprocated with the intake valve or the exhaust valve.

In a bucket-shaped member constituting such a bucket-type tappet, it is required that a disc-shaped portion having an outer surface with which a cam portion provided on a camshaft slides has excellent wear resistance. In addition, it is required to reduce the weight in order to reduce the inertial mass in the reciprocating motion accompanying the intake valve or the exhaust valve. Therefore, of the disc-shaped portion and the cylindrical portion constituting the bucket-shaped member, the disc-shaped portion is formed of a wear-resistant alloy material, and the outer peripheral surface is brought into contact with the inner surface of the guide hole in the cylinder head. It has been proposed that the cylindrical portion be formed of a light alloy material, for example, an aluminum alloy material for the purpose of weight reduction. However, in a bucket type tappet in which the cylindrical portion constituting the bucket-shaped member is formed of an aluminum alloy material, when the cylinder head is formed of an aluminum alloy material, the guide hole of the cylinder head is formed. The surface of the aluminum alloy material forming the cylindrical portion of the bucket-shaped member is brought into sliding contact with the surface of the aluminum alloy material forming the inner surface portion, and thus a state of sliding contact between the aluminum alloy materials is brought about. Therefore, there is a problem that seizure of the tubular portion of the bucket-shaped member is easily caused.

Therefore, in order to cope with such a problem, for example, in JP-A-62-63105, the disk-shaped portion and the cylindrical portion constituting the bucket-shaped member are made of a wear-resistant metal material and a light-weight material, respectively. In addition to being formed of an alloy material, the peripheral end surface of the disc-shaped portion and the outer peripheral surface of the cylindrical portion are covered with an iron-based metal plating layer formed by plating an iron-based metal. A bucket type tappet is disclosed, and in such a bucket type tappet, even when the cylinder head is used in an engine formed of an aluminum alloy material, an aluminum alloy material forming an inner surface portion of a guide hole in the cylinder head is used. The surface of the iron-based metal plating layer covering the peripheral end surface of the disc-shaped portion and the outer peripheral surface of the cylindrical portion of the bucket-shaped member is brought into sliding contact with the surface. Thus, a situation in which the tubular portion of the bucket-shaped member is seized is avoided.

(Problems to be Solved by the Invention) However, in the bucket type tappet, a cylindrical portion constituting the bucket-shaped member is formed of a light alloy material for the purpose of weight reduction, and an inner surface of a guide hole in a cylinder head. In order to avoid seizure due to sliding contact with the part, when the outer surface is to be covered with an iron-based metal plating layer, at the time of manufacture, a bucket including a cylindrical portion formed of a light alloy material The step of plating an iron-based metal on the surface of the shaped member is required, and the production process becomes complicated and the number of man-hours is increased, resulting in a disadvantage that the production cost is significantly increased.

In view of the above, the present invention is configured to include a bucket-shaped member including a disc-shaped portion and a tubular portion formed of a light metal material engaged with the disc-shaped portion, and the tubular portion of the bucket-shaped member is formed of a light metal material. Despite the fact that the cylinder head is used for an engine made of a light alloy material such as an aluminum alloy material and the cylinder head is arranged in a reciprocating manner in the guide hole of the cylinder head, A bucket-type tappet of an engine, in which a tubular portion of the tubular member is prevented from seizing, and which does not lead to a complicated manufacturing process and an increase in the number of manufacturing steps, and whose manufacturing cost is relatively low, , And a method for producing the same.

(Means for Solving the Problems) In order to achieve the above-mentioned object, a bucket type tappet of an engine according to the present invention has a surface portion with which a cam portion of an engine valve mechanism slides, and has a rear surface portion. A bucket-shaped member including a disc-shaped portion provided with a joining portion and a cylindrical portion formed in a cylindrical shape from a light metal material and having one end engaged with an engaging portion provided in the disc-shaped portion. And an annular member formed of an iron-based metal material and surrounding an outer peripheral surface of the bucket-shaped member, wherein the annular member and one end of a cylindrical portion of the bucket-shaped member are engaged with the disk. It is caulked and connected to the engaging part provided in the shape part.

Further, the method of manufacturing a bucket type tappet for an engine according to the present invention relates to a method for manufacturing a valve portion of an engine having a front surface portion with which a cam portion slides and having an engagement portion provided on a rear surface side. At the joint, one end of a cylindrical portion formed into a cylindrical shape with a light metal material is engaged to form a bucket-shaped member, and the outer peripheral surface of the bucket-shaped member is formed by an annular member formed of an iron-based metal material. Encircling, caulking is performed on one end of the cylindrical portion of the annular member and the bucket-shaped member and the engaging portion provided on the disk-shaped portion engaged with the cylindrical member, and thereafter, the machine is applied to the outer peripheral surface of the annular member. The bucket type tappet is obtained by performing a grinding process.

(Operation) In the bucket type tappet of the engine according to the present invention configured as described above, the bucket-shaped member has a cylindrical portion formed of a light metal material, thereby reducing the overall weight. And the inertial mass in reciprocating with the intake valve or the exhaust valve is reduced.
An outer peripheral surface of the bucket-shaped member is surrounded by an annular member formed of an iron-based metal material, and the annular member and one end of the cylindrical portion of the bucket-shaped member are provided on a disk-shaped portion engaged with the annular member. The cylinder head is used in an engine made of a light metal material such as an aluminum alloy material, and reciprocates in a guide hole in the cylinder head. In the case of disposing the bucket-shaped member, the situation where the tubular portion of the bucket-shaped member is seized is avoided, and the coupling strength between the disk-shaped portion and the tubular portion forming the bucket-shaped member is increased. Moreover, the manufacturing process is not complicated and the number of manufacturing steps is not increased, so that the manufacturing cost is not increased.

Further, according to the method of manufacturing the bucket type tappet of the engine according to the present invention as described above, the bucket type tappet of the engine according to the present invention can be easily obtained with a relatively small number of manufacturing steps.

(Example) FIG. 2 shows an example of a bucket type tappet of an engine according to the present invention, together with a valve train of an engine to which the tappet is applied.

In FIG. 2, for example, a valve mechanism for driving a valve member 5 which is disposed on the intake side in a cylinder head 4 formed between an aluminum alloy material and disposed between a cylinder block 2 and a head cover 3. Is shown, a combustion chamber 9 is formed above a piston 8 disposed in a cylinder 7 of the engine 1, and the combustion chamber 9 is provided in a cylinder head 4. Intake port
The downstream open end 10a in 10 is connected. The downstream opening end 10a of the intake port 10 is opened and closed by a valve member 5 which reciprocates according to the rotation of a cam portion 17 provided on a cam shaft 16 positioned above the cylinder head 4. As a result, a state of communicating with the combustion chamber 9 or a state of being cut off from the combustion chamber 9 is taken.

The valve member 5 is a guide member disposed on the cylinder head 4.
At the upper end of the stem portion 5a which reciprocates within 13, a spring cap 15 is provided, one end of which is pressed against a coil spring 14 arranged around the stem portion 5a. In FIG. 15, a hydraulic lash adjuster 20 is incorporated, and the rotation of a cam portion 17 provided on a cam shaft 16 reciprocates via a bucket type tappet 25 which is an example of a bucket type tappet of the engine according to the present invention. And transmitted to the valve member 5
There is a state in which the coil spring 14 is pressed down while compressing it, and a state in which the coil spring 14 is pushed up in accordance with the extension of the coil spring 14.

The bucket type tappet 25 reciprocates in the guide hole 18 provided in the cylinder head 4 along with the valve member 5, and is formed of a wear-resistant metal material as shown in FIG. A main body 26 having a surface portion 26A with which a cam portion 17 provided on 16 is in sliding contact, and an annular body having an outer diameter smaller than the outer diameter of the main body 26 to form a back surface of the main body 26 Protruding from the portion 26B, and an annular groove 2
A disk-shaped portion 28 having an engaging portion 27 provided with 7a, and a light metal material, for example, an aluminum alloy material, are formed in a cylindrical shape as a whole, and have a cylindrical upper half portion 29A and a cylindrical lower half portion. Part 29B is provided, and the cylindrical upper half body part 2 forming one end thereof is provided.
A bucket member 30 having an upper end portion 9A and a cylindrical portion 29 engaged with an engaging portion 27 of a disc-shaped portion 28.
It is comprised including. A support portion 31 is provided inside the cylindrical portion 29 forming the bucket member 30 and provided with a cylindrical portion 31a that protrudes from the inner surface of the cylindrical portion 29 and supports the hydraulic lash adjuster 20. ing.

The bucket member 30 includes an annular member 33 formed of an iron-based metal material and a cylindrical upper half body portion 29A of the cylindrical member 29 and the peripheral end surface of the disk-shaped portion 28 forming the outer peripheral surface of the bucket member 30. Are fitted so as to surround the outer peripheral surface portion.
The upper end portion of the annular member 33, and the engagement portion between the upper end portion of the cylindrical upper half portion 29A of the tubular member 29 and the annular groove 27a of the disc-shaped portion 28 are subjected to caulking, As a result, the engagement portion 27 provided on the disc-shaped portion 28 and one end of the tubular portion 29 are firmly connected. The outer peripheral surface of the annular member 33 has been subjected to mechanical grinding throughout.

The cylindrical upper half part 29A and the cylindrical lower half part 2 in the cylindrical part 29
9B, a through hole 29a is provided, and the bucket member 3
0 is disposed in a guide hole 18 provided in the cylinder head 4, as shown in FIG.
The lubricating oil from the oil passage 35 provided in the portion where the guide hole 18 is formed is supplied to the inside of the tubular upper half portion 29A in the tubular portion 29 through the through hole 29a.

The hydraulic lash adjuster 20 supported by the support portion 31 provided inside the cylindrical portion 29 forming the bucket member 30 includes a cylindrical upper half body portion in the cylindrical portion 29.
An oil storage unit 21 in which lubricating oil supplied to the inside of 29A is introduced through an oil introduction passage 36 provided in a back surface portion 26B of the disc-shaped portion 28, and a variable volume chamber 22 between the oil storage unit 21 A sliding portion 23 formed therein, and an oil adjusting mechanism 24 disposed in the variable volume chamber 22 for selectively communicating the variable volume chamber 22 and the oil storage section 21 with each other.
As shown in the figure, the end face 23a of the sliding portion 23 is
And applies a pressing force to the valve member 5.

In the bucket type tappet 25 configured as described above, the disc-shaped portion 28 and the cylindrical portion 29 forming the bucket member 30 are formed of a wear-resistant metal material and a light metal material, respectively. This suppresses abrasion of the cam portion 17 provided on the camshaft 16 due to sliding contact and reduces the overall weight. Further, the engaging portion 27 provided on the disc-shaped portion 28 and the cylindrical portion One end of 29 is an annular member 33
And firmly joined by caulking.

Further, the cylindrical upper half portion 29A of the cylindrical portion 29 forming the bucket member 30 is affected by the vibration caused by the sliding contact of the cam portion 17 provided on the camshaft 16 with the disc-shaped portion 28, and the cylinder It is a part that is easily brought into contact with the inner surface of the guide hole 18 provided in the head 4,
An annular member 33 made of an iron-based metal material is fitted on the peripheral end surface of the disk-shaped portion 28 and the outer peripheral surface of the cylindrical upper half body portion 29A in the cylindrical portion 29. A situation in which the cylindrical upper half portion 29A of the cylindrical portion 29 is in direct sliding contact with the inner surface of the guide hole 18 of the cylinder head 4 to cause wear and seizure is avoided. Further, the annular member 33
The guide hole in the cylinder head 4 is formed by performing mechanical grinding on the entire outer peripheral surface and correcting the distortion generated when the caulking is performed.
The sliding characteristics within 18 are considered to be good.

The bucket type tappet 25 which is an example of the bucket type tappet of the engine according to the present invention configured as described above is used.
Is manufactured as follows.

First, as shown in FIG. 3A, a cylindrical portion 29 formed of a light metal material is engaged with an engagement portion 27 provided with an annular groove 27a in a disk-shaped portion 28 formed of a wear-resistant metal material. By engaging the upper end of the cylindrical upper half 29A,
The bucket member 30 is formed. Next, an annular member 33 formed of an iron-based metal material is formed on the peripheral end surface of the disc-shaped portion 28 forming the bucket member 30 and the outer peripheral surface of the cylindrical upper half portion 29A in the cylindrical portion 29, for example. , By press-fitting, as shown in FIG. 3B, the upper end of the annular member 33,
And an annular groove 27a provided in the engaging portion 27 of the disc-shaped portion 28
Then, a portion of the cylindrical portion 29 that engages with the upper end of the cylindrical upper half body portion 29A is subjected to caulking by a roller 38 that is brought into contact with the outer peripheral surface of the annular member 33. By such caulking, the inner surface of the upper end portion of the cylindrical upper half portion 29A in the cylindrical portion 29 is deformed, enters the annular groove 27a provided in the engaging portion 27 of the disk-shaped portion 28, and 33, one end of the cylindrical portion 29, and the engaging portion 27 provided on the disc-shaped portion 28 are firmly connected.

Subsequently, the entire outer peripheral surface portion of the annular member 33 is subjected to mechanical grinding using a grindstone 39 as shown in FIG. 3C to form the bucket member 30 having a smooth outer peripheral surface. Thus, a bucket type tappet 25 is obtained.

In this manner, the outer peripheral surface of the bucket member 30 formed by the disc-shaped portion 28 and the cylindrical portion 29 is crimped by fitting the annular member 33 formed of an iron-based metal material, A bucket member formed by firmly connecting the disk-shaped portion 28 and the cylindrical portion 29 by a relatively simple process of merely performing mechanical grinding on the outer peripheral surface of the annular member 33.
It is possible to obtain a bucket-type tappet 25 in which an annular member 33 formed of an iron-based metal material having good sliding characteristics with respect to the guide hole 18 provided in the cylinder head 4 is provided on the outer peripheral surface of the cylinder head 4. it can.

In the above-described example, the annular member 33 is fitted to the outer peripheral surface of the bucket member 30 by press fitting, but instead of such a member, an iron-based metal material formed by forging is used. May be obtained by being wound around the outer peripheral surface of the bucket member 30.Also, the belt-shaped member may be disposed on the outer peripheral surface of the bucket member 30 by casting using an iron-based metal material. It may be assumed. Further, the annular member 33 may surround not only the cylindrical upper half portion 29A but also the cylindrical lower half portion 29B in the cylindrical portion 29.

(Effects of the Invention) As is clear from the above description, in the bucket type tappet of the engine according to the present invention, the bucket-shaped portion formed of the disc-shaped portion and the cylindrical portion formed of a light metal material engaged with the disc-shaped portion. The bucket-shaped member has a cylindrical portion formed of a light metal material, so that the overall weight is reduced, and the bucket-shaped member reciprocates with the intake valve or the exhaust valve. The inertial mass is reduced. Further, the outer peripheral surface of the bucket-shaped member is surrounded by an annular member formed of an iron-based metal material, and the annular member and one end of the cylindrical portion of the bucket-shaped member are provided on a disc-shaped portion engaged with the annular member. The cylinder head is used in an engine made of a light metal material such as an aluminum alloy material, and reciprocates in a guide hole in the cylinder head. When being distributed by
A situation in which the tubular portion of the bucket-like member is seized is avoided, and the coupling strength between the disc-like portion and the tubular portion forming the bucket-like member is increased, and the manufacturing process is complicated. Therefore, it is possible to obtain the semiconductor device at a relatively low manufacturing cost without causing an increase in the number of manufacturing processes.

Further, according to the method of manufacturing the bucket type tappet of the engine according to the present invention, the bucket type tappet of the engine according to the present invention as described above can be easily manufactured with relatively simple steps and relatively small man-hours. Obtainable.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an example of a bucket type tappet of an engine according to the present invention, and FIG. 2 is a schematic sectional view showing an example of a bucket type tappet of an engine according to the present invention together with a valve train of an engine to which the tappet is applied. FIGS. 3A to 3C are views for explaining the manufacturing process of the example shown in FIG. In the figure, 1 is an engine, 4 is a cylinder head, 5 is a valve member, 16 is a cam shaft, 17 is a cam portion, 18 is a guide hole, 25
Is a bucket type tappet, 28 is a disk-shaped portion, 29 is a cylindrical portion, 30 is a bucket member, and 33 is an annular member.

Claims (2)

(57) [Claims] 1. A disc-shaped portion having a front surface portion with which a cam portion in a valve train mechanism of an engine comes into sliding contact with an engagement portion on a back surface side, and a cylindrical shape made of a light metal material, one end of which is formed. A bucket-shaped member having a cylindrical portion whose portion is engaged with an engagement portion provided on the disc-shaped portion, and an annular member formed of an iron-based metal material and surrounding an outer peripheral surface of the bucket-shaped member And the annular member and one end of the cylindrical portion of the bucket-shaped member are caulked to an engaging portion provided on the disc-shaped portion engaging with the one end. A bucket type tappet of an engine characterized by the following. 2. An engaging portion of a disc-shaped portion having a front surface portion with which a cam portion in an engine valve operating mechanism slides and having an engaging portion provided on a back surface side is formed into a cylindrical shape by a light metal material. One end of the formed cylindrical portion is engaged to form a bucket-shaped member, and the outer peripheral surface of the bucket-shaped member is surrounded by an annular member made of an iron-based metal material. When one end of the cylindrical portion of the member is engaged with the one end, a caulking process is performed on the engaging portion provided on the disc-shaped portion, and thereafter, a mechanical grinding process is performed on an outer peripheral surface portion of the annular member. And obtaining a bucket-type tappet by applying the above method.