JPH06212915A - Manufacture of valve lifter of engine - Google Patents

Abstract

PURPOSE:To provide a manufacturing process of a valve lifter of engine, by which the weight of the whole can be reduced without deteriorating the wear resistance. CONSTITUTION:In the manufacturing process of a valve lifter of engine, a lifter body 2 is molded by using a workpiece raw material made of an aluminum alloy compound material, a wear-resistant member 3 is arranged only in a place which corresponds to the contact face 2a of the lifter body 2 with a valve driving cam, and the workpiece raw material of the lifter body 2 and the wear-resistant member 3 are integrally bonded by solid phase-diffusion bonding to obtain a valve lifter 1.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for manufacturing a valve lifter for engine valve parts of two-wheeled vehicles, four-wheeled vehicles and the like.

[0002]

2. Description of the Related Art Normally, a valve lifter of an engine valve component of a two-wheeled vehicle, a four-wheeled vehicle, etc., is in direct sliding contact with a cam shaft rotating at a high speed, and therefore high wear resistance is required. For example, in an OHC (overhead camshaft) type valve operating mechanism as shown in FIG. 9, 51 is a cylinder block, 52 is a camshaft, 53 is a valve lifter, 5
4 is a valve, 55 is a valve retainer, 56 is a valve cotter, 57 is a valve spring, 58 is a spring seat, 59 is a stem seal, 60 is a valve guide, 61 is a valve seat, 62 is a combustion chamber, and the valve 54 is a camshaft. 52 is driven via a valve lifter 53. That is, as the camshaft 52 rotates, the valve 54 moves up and down, and the intake of the air-fuel mixture or the exhaust of the combustion gas is performed.

The valve lifter 53 has a camshaft 5
It plays a role of smoothly transmitting the force of 2 to the valve 54 along the vertical direction, and a thin disk-shaped shim is installed on the contact surface between the valve lifter 53 and the camshaft 52 for the purpose of adjusting the valve lift amount. It may be done. By the way, the valve lifter 53 is in contact with the top chill layer of the camshaft 52, which is approximately H _R C60 ± 4, and therefore, the wear resistance is required as described above. For example, a comparison with JIS SKD11 is required. In many cases, it is made of a hard material. On the other hand, since the valve lifter 53 normally repeats the reciprocating motion of up and down or left and right (a horizontally opposed engine), it is desirable that the valve lifter 53 be as light as possible.

[0004]

However, in the prior art, the wear resistance of the valve lifter 53 has been emphasized, and since the whole is manufactured using an iron-based material having a large mass, the weight reduction from the current state is achieved. Was difficult, and the weight reduction of the valve lifter 53 was not sufficient. Therefore, it is difficult to reduce the inertial force of the reciprocating motion of the valve lifter 53, and it has been impossible to achieve high engine output and low fuel consumption.

The present invention has been made in view of the above circumstances, and an object thereof is to provide a method of manufacturing an engine valve lifter capable of reducing the overall weight without impairing wear resistance. To do.

[0006]

In order to solve the above-mentioned problems of the prior art, in the present invention, a lifter body is molded using an aluminum alloy or an aluminum alloy composite material, and a valve driving cam of the lifter body is formed. A wear resistant member is arranged only at a portion corresponding to a contact surface with the valve lifter, and the lifter body and the wear resistant member are integrally bonded by solid phase diffusion bonding to obtain a valve lifter.

According to another aspect of the present invention, a valve lifter is obtained by molding a lifter body using an aluminum alloy or an aluminum alloy composite material, and aggregating composite particles on a contact surface of the lifter body with a valve driving cam. I am trying.

[0008]

In the engine valve lifter manufacturing method according to the present invention, the lifter body is made of an aluminum alloy or an aluminum alloy composite material, and a wear resistant member is provided only on the contact surface of the lifter body with the valve driving cam. Alternatively, since a cohesive layer of composite particles is formed on the contact surface, weight reduction can be achieved while imparting necessary wear resistance to the contact surface with the cam, and both weight reduction and wear resistance are achieved. An excellent quality valve lifter can be obtained.

[0009]

DESCRIPTION OF THE PREFERRED EMBODIMENTS The present invention will be described in detail below based on the illustrated embodiments.

1 to 5 show an embodiment of a method for manufacturing an engine valve lifter according to the present invention. In the figure, reference numeral 1 denotes a valve lifter obtained by the manufacturing method of the present embodiment. This valve lifter 1 is used in an OHC type valve operating mechanism, and the force of a valve driving cam shaft (not shown) is not shown along the vertical direction. Plays a role in transmitting to the valve. Therefore, as shown in FIGS. 1 and 2, the valve lifter 1 includes a lifter body 2 integrally molded in a bottomed cylindrical shape using an aluminum alloy or an aluminum alloy composite material, and a cam shaft (not shown) of the lifter body 2. And a contact surface 2a for contact with the wear resistant member 3 in the form of a thin disk.

The lifter body 2 and the wear resistant member 3 are also provided.
And are bonded by the solid phase diffusion bonding method. Intrinsic diffusion bonding referred to here is to provide a matrix of a composite material and an insert metal that does not adversely affect the composite state of the composite material between the surfaces to be joined of the metal material by combining with the matrix of the composite material and the metal material. At the same time, a pressure P and a temperature T are applied to these to diffuse them through the insert metal or into the joining member, thereby joining the two in a solid state. According to this joining method,
It becomes possible to join the members to be joined together more firmly and more reliably than by simply installing or brazing.

As shown in FIG. 4, the lifter main body 2 is made of, for example, a JIS AC8A alloy, a composite material (PRM) in which SiC particles having a diameter of 5 μm are added in an amount of 10 mass%.
It is formed by using a processing material 12 that is processed to have a size of 20 mm. The wear-resistant member 3 may be, for example, JIS
It is formed by processing the SKD 11 into φ12 × 1.5 mm. As the insert metal 4 described above, a pure Cu insert having a thickness of 50 μm is used.

Further, in the manufacturing method of this embodiment, as shown in FIG. 5, a vacuum container 5 whose inside is held in a vacuum atmosphere is used.
And a pair of pressurizing jigs 6 and 7 whose tip portions are disposed in the vacuum container 5 to press and sandwich the wear resistant member 3, the insert metal 4 and the processing material 12 at a predetermined pressure P, and the processing material. A heater 8 that heats 12 and the like to a predetermined temperature is used. The pressurizing jigs 6 and 7 press the processing material 12 and the like arranged between them from both sides, and are slidably arranged in the vacuum container 5 via the vacuum seals 9 and 10. On the other hand, the heater 8 is arranged around the tip of the pressurizing jigs 6 and 7 located inside the vacuum container 5, and is a work material 12 or the like sandwiched between the pressurizing jigs 6 and 7. Is arranged so as to cover.

According to the manufacturing method of this embodiment, the valve lifter 1
In order to manufacture, the work material 12 and the wear resistant member 3 of the lifter main body 2 are first processed into the above-mentioned dimensions, and the joint surface of the wear resistant member 3 is ground and finished with No. 1000 emery paper. The joint surface of the processing material 12 corresponding to the contact surface 2a with the cam shaft (not shown) of the main body 2 is finished to have a ten-point average roughness of 0.8 μm. Then, after degreasing these joint surfaces with hexane, the insert metal 4 having the above dimensions is sandwiched therebetween, and as shown in FIG. 4, the joint surface of the wear resistant member 3 is arranged downward and fitted onto the joint surface of the work material 12. Put in.

Next, the wear resistant member 3, the insert metal 4 and the work material 12 are placed between the pressing jigs 6 and 7 in the vacuum container 5, and the heater 8 is used in a vacuum atmosphere of about 0.1 Pa. While heating to a temperature of about 798 K, a pressure P of about 1 MPa is applied for about 3.6 ks by the pressing jigs 6 and 7 (see FIG. 5). Then, both the wear resistant member 3 and the work material 12 are joined and integrated with each other by solid phase diffusion joining, and Cu and A as shown in FIG.
A third layer A in which components of 1, Fe, and Si are mixed is formed. Further, an agglomerated layer B of SiC particles having a thickness of about 500 μm is formed at the boundary portion on the side of the processing material 12 made of a composite material.

After that, the wear resistant member 3 and the processed material 1
2 is sufficiently cooled and taken out from the vacuum container 5, and the valve lifter 1 is machined into a bottomed cylindrical shape as shown in FIGS. 1 and 2 to finish, and a lifter body 2 molded from an aluminum alloy composite material is obtained. A valve lifter 1 including a wear resistant member 3 bonded only to a contact surface 2a of the lifter body 2 with a cam shaft (not shown) is obtained.

In the manufacturing method of this embodiment, the lifter main body 2 which constitutes the majority of the valve lifter 1 is molded from the processing material 12 of aluminum alloy composite material, and the lifter main body 2 and the cam shaft (not shown) are formed. Since the valve lifter 1 is manufactured by integrally joining the wear resistant material 3 only to the contact surface 2a, it is possible to manufacture a component that is approximately 50% lighter than the conventional product, and the weight of the valve lifter 1 can be reduced. In addition, due to the existence of the wear resistant member 3 joined to a necessary portion, wear resistance similar to that of the valve lifter made entirely of iron material can be obtained. Moreover, since the lifter main body 2 and the wear resistant member 3 of the present embodiment are joined by solid phase diffusion joining, both of them can be joined securely and the integrated valve lifter 1 can be manufactured. .

6 to 8 show another embodiment of the method of manufacturing the valve lifter for the engine according to another embodiment of the present invention. In the figure, 21 is a valve lifter obtained by the manufacturing method of the present embodiment. This valve lifter 21 is also used in an OHC type valve operating mechanism and plays the same role as the above-mentioned invention. Further, the valve lifter 21 includes a lifter body 22 integrally formed in a bottomed cylindrical shape using an aluminum alloy or an aluminum alloy composite material, and a contact surface 22 between the lifter body 22 and a valve driving cam shaft (not shown).
It is composed of an aggregate layer 23 of composite particles (SiC particles) formed in a.

The lifter body 22 is, for example, JIS A
10 mass of SiC particles with a diameter of 5 μm on C8A alloy
%, The composite material (PRM) is processed into a φ25 × 20 mm processed material 32. Moreover, as the insert metal 24, pure C having a thickness of 50 μm is used.
u inserts are used.

In the manufacturing method of this embodiment, as shown in FIG. 7, the same vacuum container 5, a pair of pressurizing jigs 6, 7, a heater 8 and vacuum seals 9, 10 as in the above-described invention are used. Further, the carbon table 25 on which the processing material 32 is installed is used. The carbon base 25 is provided on the pressing jig 7 located below the processing material 32 and the insert metal 24.
It is designed to be installed on top of.

The valve lifter 2 is manufactured by the manufacturing method of this embodiment.
In order to manufacture 1, first, the processing material 3 of the lifter main body 22
2 is processed into the above-mentioned size, and the surface of the lifter main body 22 that becomes the contact surface 22a with the cam shaft (not shown) is ground and finished with No. 700 emery paper. Then, the bonding surface of the processing material 32 is faced downward, and the insert metal 24 having the above-mentioned dimensions is sandwiched therebetween and placed on the carbon table 25 in the vacuum container 5.

Next, the processing material 32 and the insert metal 24 are heated in a heater 8 in a vacuum atmosphere of about 0.1 Pa.
Is heated to a temperature of about 798 K and a pressure P of about 1 MPa is applied for about 3.6 ks by the pressing jigs 6 and 7 (see FIG. 7). Then, the agglomeration layer 23 of SiC particles having a thickness of about 500 μm is formed at the contact portion of the processing material 32 made of the Al composite material with the carbon base 25, as shown in FIG. The insert metal 24 was absorbed in the composite matrix of the work material 32.

After that, the work material 32 is sufficiently cooled and taken out from the vacuum container 5, and the valve lifter 21 is worked into a bottomed cylindrical shape as shown in FIG. A valve lifter 21 including a lifter main body 22 and an agglomeration layer 23 formed on a contact surface 22a of the lifter main body 22 with a cam shaft (not shown) is obtained.

In the manufacturing method of the present embodiment, the lifter main body 22 which constitutes the majority of the valve lifter 21 is formed of the aluminum alloy composite material 32, and the lifter main body 22 and the cam shaft (not shown) are formed. Contact surface 22a
Since the valve lifter 21 is manufactured by forming the SiC particle agglomeration layer 23 in the above, the weight of the valve lifter 21 can be reduced in the same manner as the above-mentioned invention, and the SiC particle agglomeration layer 23 formed at a necessary position can be formed. Due to its existence, it is possible to obtain almost the same wear resistance as a valve lifter made entirely of an iron material.

The embodiment of the present invention has been described above.
The present invention is not limited to the embodiments described above, and various modifications can be made based on the technical idea of the present invention. For example, it goes without saying that conditions such as temperature and pressure in the above-described embodiments can be appropriately selected according to the size and shape of the valve lifters 1 and 21 to be manufactured.

[0026]

As described above, in the method of manufacturing the engine valve lifter according to the present invention, the lifter body is molded using an aluminum alloy or an aluminum alloy composite material, and the contact surface of the lifter body with the valve driving cam is formed. Since the wear resistant member is arranged only at the corresponding position and the lifter body and the wear resistant member are integrally bonded by solid phase diffusion bonding to obtain the valve lifter, the lifter body and the wear resistant member are It is possible to manufacture a highly reliable valve lifter in which the valve member is securely joined to the elastic member, and it is possible to reduce the weight of the valve lifter without impairing wear resistance. Therefore, if the valve lifter manufactured by the manufacturing method of the present invention is used in an engine, the inertial force of the reciprocating motion of the valve can be reduced, and the engine can have high output and low fuel consumption.

Further, in another method of manufacturing a valve lifter for an engine according to the present invention, a lifter body is molded using an aluminum alloy or an aluminum alloy composite material, and composite particles are provided on a contact surface of the lifter body with a valve driving cam. Since the valve lifter was obtained by aggregating
It is possible to manufacture a high-quality valve lifter that has both a lightweight structure and wear resistance with a simple structure.

[Brief description of drawings]

FIG. 1 is a perspective view showing a valve lifter manufactured by a manufacturing method according to an embodiment of the present invention.

FIG. 2 is a sectional view showing the valve lifter.

FIG. 3 is a micrograph showing a microstructure in the vicinity of a joint between a work material of a lifter main body which constitutes the valve lifter and a wear resistant member.

FIG. 4 is a perspective view showing a state before the wear resistant member is joined to the material for working the lifter body.

FIG. 5 is a conceptual diagram showing a processing material and a wear resistant member of a lifter body arranged between pressurizing jigs in a vacuum container used in the above manufacturing method.

FIG. 6 is a cross-sectional view showing a valve lifter manufactured by a manufacturing method according to another embodiment of the present invention.

FIG. 7 is a conceptual diagram showing a processing material of a lifter body arranged between pressing jigs in a vacuum container used in the above manufacturing method.

FIG. 8 is a cross-sectional view showing a processing material of the lifter body on which an agglomerated layer of SiC particles is formed.

FIG. 9 is a sectional view showing an OHC type valve mechanism.

[Explanation of symbols]

 1, 21 Valve lifter 2, 22 Lifter body 2a, 22a Contact surface 3 Wear resistant member 4, 24 Insert metal 5 Vacuum container 6, 7 Pressurizing jig 8 Heater 9, 10 Vacuum seal 12, 32 Processing material 23 Aggregation layer 25 Carbon stand

Claims (2)

[Claims] 1. A lifter body is molded using an aluminum alloy or an aluminum alloy composite material, and a wear resistant member is disposed only at a portion corresponding to a contact surface of the lifter body with a valve driving cam. A method of manufacturing a valve lifter for an engine, wherein the valve lifter is obtained by integrally bonding the wear resistant member and the wear resistant member by solid phase diffusion bonding. 2. A valve lifter is obtained by molding a lifter main body using an aluminum alloy or an aluminum alloy composite material, and agglomerating composite particles on a contact surface of the lifter main body with a valve driving cam. And a method for manufacturing an engine valve lifter.