JPH0559033U - Cam - Google Patents

Abstract

(57) [Summary] [Object] An object of the present invention is to provide a structure in which the weight of the cam piece can be reduced in the assembly type cam, thereby further promoting the weight reduction of the entire camshaft. To get a cam. According to the present invention, in a structure of a cam piece 3 which is integrated by being assembled with a cam shaft 2, a surface (A) contacting a driven member and a range (radial direction from this surface to the cam shaft) ( It is characterized in that the thickness along the axial direction of the camshaft 2 is different between B) and.

Description

[Detailed description of the device]

[0001]

[Industrial applications]

 BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a cam, and more particularly, to a structure of an assembled cam.

[0002]

[Prior Art]

 A cam used in an automobile engine is a cast product in which a cam piece for setting a cam profile and a shaft are integrated.

By the way, in recent years, the cam piece and the cam shaft described above are separately configured for the purpose of simplifying the mold manufacturing in the casting process according to the specifications and further reducing the weight of the cam shaft. Assembled cams have been proposed in which a cam piece is cast or joined to the shaft to be attached later.

[0004]

[Problems to be solved by the device]

 However, in the above-mentioned cam, the cam piece integrated with the cam shaft is simply divided while keeping the shape of the cam piece in the structure so far, so that the weight of the cam piece itself should be reduced. However, the overall weight of the camshaft was not sufficiently reduced.

Therefore, in view of the above-mentioned problems in the conventional assembling type cam, the object of the present invention is to realize the weight reduction of the cam piece, thereby further promoting the weight reduction of the entire camshaft. To get a cam with.

[0006]

[Means for Solving the Problems]

 In order to achieve this object, the present invention has a structure in which a cam piece is integrated by being assembled to a cam shaft, and has a surface that comes into contact with a driven member and a range from this surface to the cam shaft in the radial direction. Is characterized in that the thickness of the camshaft along the axial direction is changed.

Further, the present invention is characterized in that the thickness in the range along the radial direction up to the cam shaft is set smaller than the thickness of the surface contacting the driven member.

[0008]

[Action]

 According to the present invention, it is possible to reduce the weight while ensuring the area in contact with the driven member.

[0009]

【Example】

 1 and 2, the details of the embodiment of the present invention will be described below. FIG. 1 is a cross-sectional view as seen from a direction crossing the axial direction of the camshaft. In FIG. 1, the cam 1 is composed of a camshaft 2 and a cam piece 3. In the case of this embodiment, the cam piece 3 is processed with a cam profile capable of setting a predetermined cam lift by sintering, and the thickness of the cam shaft 2 along the axial direction is as follows. It is set. That is, as shown in FIG. 2, the outer peripheral surface of the cam piece 3 that contacts a driven member such as a tappet or a cam follower (A) is different from the thickness (B) in the range from this surface to the cam shaft 2. ) Is specified thinly. The thickness (A) of the surface contacting the driven member described above is set for the purpose of ensuring an area where the strength obtained from the contact pressure with the driven member can be set, and The thickness (B) in the range up to the camshaft 2 is set for the purpose of reducing the weight while ensuring the longitudinal elastic modulus for the strength required for the surface contacting the driven member. Has been done.

Further, for example, serrations are formed on the inner peripheral surface of the cam piece 3, and serrations are formed by engaging a screw formed at a cam piece mounting position on the cam shaft 2 side with the serrations. The cam piece 3 is crimped and joined to the cam shaft 2 by crushing the screw.

Since the present embodiment has the above-described structure, for example, the camshaft 2 is manufactured by casting and prepared in an assembly line, and the campiece 3 is attached to the camshaft 2. The cam piece 3, which is manufactured by sintering separately from the cam shaft 2, is prepared in an assembling line, and is pushed into a screw portion formed on the cam shaft 2 in the assembling line to cause serration of the inner peripheral surface. The serrations and threads of the screw that are generated when meshing with the screw are crushed together, and are crimped and fixed in that position.

According to the present embodiment, the camshaft and the cam piece are formed separately, and the cam piece is manufactured by sintering. Therefore, the shape of the cam piece can be changed according to the specifications of the cam. In addition, it is possible to make the camshafts common in this case, and this makes it possible to change the manufacturing of the casting mold for the camshaft in accordance with changes in specifications. Since it can be avoided, the manufacturing cost can be reduced.

In the above-described embodiment, the thickness of each part of the cam piece 2 is reduced in the range up to the cam shaft with respect to the surface that contacts the driven member. It is also possible to set the relationship of.

[0014]

[Effect of the device]

 As described above, according to the present invention, in the cam piece assembled to the camshaft, if the thickness along the axial direction of the camshaft is different between the surface contacting the driven member and the range from this surface to the camshaft. By reducing the thickness of the camshaft, it is possible to reduce the weight of the cam piece, which in turn makes it possible to reduce the weight of the camshaft as a whole. .

[Brief description of drawings]

FIG. 1 is a cross-sectional view of an axial cross section of a cam shaft for explaining the overall structure of a cam according to an embodiment of the present invention.

FIG. 2 is a cross-sectional view in the direction indicated by the reference line in FIG.

[Explanation of symbols]

1 cam 2 camshaft 3 cam piece A thickness of outer circumference of cam piece B thickness of outer circumference of cam piece from camshaft to camshaft

Claims (2)

[Scope of utility model registration request] 1. A structure of a cam piece integrated by being assembled to a cam shaft, wherein a surface contacting a driven member and a range extending from this surface to the cam shaft in a radial direction are arranged in the axial direction of the cam shaft. A cam featuring different thicknesses along it. 2. The cam according to claim 1, wherein a thickness of a surface contacting the driven member is set to be thin in a range along a radial direction up to the cam shaft.