JP2010025013A - Camshaft device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a camshaft device which can reduce cost and weight while preventing the generation of center deviation in each shaft of a camshaft, and a phase shift in a circumferential direction. <P>SOLUTION: The device includes a camshaft 10, a plurality cam pieces 20 and a rolling bearing 31 arranged on an outer peripheral surface closer to one end of the camshaft 10. A shaft end component 16 is mounted at one end of the camshaft 10. The camshaft 10 is formed of a metal pipe material 110. A flange 11 is formed at one end of the camshaft 10 by the radially-outward plastic transformation of an end cylinder 111 over a prescribed length from an end surface of the metal pipe material 110. A knock pin 13 positioning and mounting the shaft end component 16 is driven into a predetermined position of the flange 11. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a camshaft device.

Conventionally, in a camshaft device, for example, as shown in FIG. 10, a plurality of cam pieces 220 are arranged in the axial direction of the camshaft 210, and the # 1 journal portion on the outer peripheral surface near one end of the camshaft 210. Are formed with a shaft portion 211 in which an annular oil groove 211a for constituting a sliding bearing is recessed in the outer peripheral surface, and flanges 212 and 213 which are positioned on both sides of the shaft portion 211 and receive a thrust load. ing.
The # 1 journal portion of the camshaft device is supported between the cylinder head 1 of the engine and the cam cap 2 fastened to the cylinder head 1.
Further, the # 1 journal portion receives a load from a shaft end component 216 such as a timing gear and a variable valve timing unit assembled to the shaft end of the camshaft 210.
For this reason, the outer diameter dimension of the shaft part 211 including the portion of the # 1 journal part is set substantially larger than the outer diameter dimension of the shaft part 210a in the region where the cam piece 220 of the cam shaft 210 is disposed. .
Further, in order to drive the knock pin 213 corresponding to the shaft end component 216 into the end surface of the shaft portion 211 including the portion of the # 1 journal portion, the end surface portion of the shaft portion 211 also has a required outer diameter and a large diameter. Must be formed.
For this reason, the camshaft 210 has a shaft portion 210a on which a plurality of cam pieces 220 are disposed and a shaft portion 211 that constitutes the # 1 journal portion, and both the shaft portions 210a, 210a, 211 is integrally connected by friction welding or the like.
A camshaft device having the above-described structure is disclosed in Patent Document 1, for example.
JP 2001-329885 A

By the way, in the camshaft device as shown in FIG. 10, after the shaft portion 210a on which the plurality of cam pieces 220 are disposed and the shaft portion 211 including the # 1 journal portion are individually formed, both the shafts are formed. The parts 210a and 211 must be joined together by friction welding or the like.
Furthermore, when the shaft portions 210a and 211 are coupled, a center shift between the shaft portions 210a and 211 and a phase shift in the circumferential direction may occur.

  SUMMARY OF THE INVENTION In view of the above problems, an object of the present invention is to prevent a center deviation of each shaft portion of a camshaft and a phase deviation in the circumferential direction, and to reduce the cost and weight. A shaft device is provided.

In order to achieve the above object, a camshaft device according to a first aspect of the present invention includes a camshaft, a plurality of cam pieces arranged in the axial direction of the outer peripheral surface of the camshaft, and an outer peripheral surface near one end of the camshaft. A camshaft device in which a shaft end component is attached to an end portion of the camshaft.
The camshaft is formed of a metal pipe material,
At one end of the camshaft, a flange is formed by plastically deforming an end tube portion extending in a radial direction from the end face of the metal pipe material outward in the radial direction,
A knock pin for positioning and attaching the shaft end component to a predetermined position of the flange is driven.

According to the above-described configuration, the shaft end parts (timing gear, variable valve timing unit, etc.) assembled to the shaft end of the camshaft by disposing the rolling bearing on the outer peripheral surface (# 1 journal portion) near one end of the camshaft. Can be received lighter than a plain bearing.
As a result, the outer diameter of the shaft portion of the camshaft where the plurality of cam pieces are disposed and the shaft portion constituting the # 1 journal portion can be set to the same size.
In addition, the end tube part extending over a predetermined length in the axial direction from the end face of the metal pipe material is plastically deformed radially outward to form a flange, and a knock pin corresponding to the shaft end part is driven into this flange, thereby The shaft end part can be positioned and attached without increasing the number of points.
As a result, it is possible to prevent the occurrence of a center shift and a phase shift in the circumferential direction between the shaft portion on which the plurality of cam pieces of the cam shaft are disposed and the shaft portion including the # 1 journal portion. Also, the effect is great in reducing cost and weight.

A camshaft device according to claim 2 is the camshaft device according to claim 1,
The end face of the flange is integrally formed with a fitting convex part into which the center hole of the shaft end part is fitted.

  According to the said structure, a shaft edge component can be stably attached to the same center by integrally forming a fitting convex part in the end surface of a flange.

  Next, the best mode for carrying out the present invention will be described with reference to examples.

Example 1
A first embodiment of the present invention will be described with reference to FIGS.
1 is a longitudinal sectional view showing a camshaft device according to Embodiment 1 of the present invention. FIG. 2 is a longitudinal sectional view showing a metal pipe material forming the camshaft. FIG. 3 is a longitudinal sectional view showing an initial state in which the end tube portion at one end of the metal pipe material is plastically deformed radially outward. FIG. 4 is a longitudinal sectional view showing an intermediate state in which the end tube portion of the metal pipe material is plastically deformed radially outward. FIG. 5 is a longitudinal sectional view showing a state in which the flange is formed by the end tube portion of the metal pipe material. FIG. 6 is a longitudinal sectional view showing a state in which a fitting convex portion is formed on the end face of the flange body. FIG. 7 is an explanatory view showing a state in which the rolling bearing is assembled to the shaft portion corresponding to the # 1 journal portion of the camshaft.

As shown in FIGS. 1 and 2, the camshaft device includes a camshaft 10, a plurality of cam pieces 20, a rolling bearing 31 corresponding to the # 1 journal portion, and a rolling bearing 41 corresponding to other journal portions. It is configured with.
A rolling bearing 31 (double-row angular contact ball bearing in FIG. 1) 31 corresponding to the # 1 journal portion is an outer ring 32, an inner ring 33, and a double-row rolling element disposed between these inner and outer rings (see FIG. 1). Ball) 34.
That is, the rolling bearing 31 is press-fitted in the inner ring 33 to a predetermined position on the outer peripheral surface near one end of the camshaft 10, and is recessed at positions corresponding to both end surfaces of the inner ring 33 on the outer peripheral surface near one end of the camshaft 10. By fitting retaining rings 37 and 38 such as C-rings in the annular grooves 25 and 26, the inner ring 33 of the rolling bearing 31 is fixed so as not to move in the axial direction.
Further, a flange 11 into which a knock pin 13 for positioning and attaching a shaft end component 16 such as a timing gear or a variable valve timing unit is formed at one end of the camshaft 10.

As shown in FIG. 1, on one side end surface of the flange 11 of the camshaft 10, a fitting convex portion 14 is fitted to which the center hole 17 of the shaft end component 16 is fitted. An internal thread 6 is formed with a predetermined thread depth from the center of the end face.
A center hole 17 of the shaft end component 16 and a pin hole portion 18 formed in communication with a part of the outer periphery of the center hole 17 are formed on the fitting convex portion 14 and the knock pin 13 of the flange 11 of the camshaft 10. After the insertion, the fastening bolt 5 is screwed into the female screw 6 through the flange 11 of the camshaft 10 and tightened, whereby the shaft end component 16 is attached to the flange 11 of the camshaft 10.

The camshaft 10 is formed by the metal pipe material 110 having the following processing steps.
First, as shown in FIG. 2, a metal pipe material 110 having required outer diameter dimensions, wall thickness dimensions, and length dimensions is prepared.
Next, as shown in FIGS. 3 to 5, the end tube portion 111 extending in a predetermined length in the axial direction from the end surface of the metal pipe material 110 is expanded radially outward by plastic working such as ironing and is plastically deformed. .
As a result, the disk-shaped flange 11 is formed in the end tube portion 111 of the metal pipe material 110.

Thereafter, as shown in FIG. 6, an annular fitting convex portion 14 is formed on the same center on the end surface of the flange 11 (left side surface as viewed in FIG. 6) by pressing or cutting.
A female thread 6 is formed through the flange 11 at the end of the inner peripheral surface of the metal pipe material 110.
Further, a knock pin hole 12 is formed in a predetermined position of the flange 11 by drilling with a drill or the like, and the knock pin 13 is driven into the knock pin hole 12 to constitute the camshaft 10.

As shown in FIG. 7, in order to assemble the rolling bearing 31 at a position corresponding to the # 1 journal portion of the camshaft 10, the annular grooves 25 are formed at positions corresponding to both end faces of the inner ring 33 on the outer peripheral surface near one end of the camshaft 10. 26 are recessed.
Then, with a retaining ring 37 such as a C-ring fitted in one annular groove 25 on the flange 11 side, press-fit from the tip side of the camshaft 10 to a position where the inner ring 33 of the rolling bearing 31 contacts the retaining ring 37. Is done. Then, a retaining ring 38 such as a C-ring is fitted into the other annular groove 26, whereby the rolling bearing 31 is fastened to a position corresponding to the # 1 journal portion of the camshaft 10 so as not to move in the axial direction.
Further, as shown in FIG. 1, a camshaft device is configured by assembling a plurality of cam pieces 20 and rolling bearings 41 corresponding to other journal portions in the axial direction of the outer peripheral surface of the camshaft 10. The
As is well known, the camshaft device is installed in the arc recess of the cylinder head 1 in the # 1 journal portion and other journal portions, and is pressed by a cam cap 2 that is fastened to the cylinder head 1 by a bolt (FIG. 1). reference).

In the camshaft device according to the first embodiment configured as described above, the rolling bearing 31 is disposed in the # 1 journal portion on the outer peripheral surface near the one end of the camshaft 10, so that the camshaft 10 is assembled to the flange 11 of the camshaft 10. The load from the shaft end component 16 can be easily received compared with the conventional sliding bearing.
Thus, the outer diameter of the shaft portion of the camshaft 10 where the plurality of cam pieces 20 are disposed and the shaft portion constituting the # 1 journal portion can be set to the same size.
As shown in FIGS. 2 to 5, the flange 11 is formed by plastically deforming the end tube portion 111 extending from the end face of the metal pipe material 110 in the axial direction outward in the radial direction. Further, by driving the knock pin 13 corresponding to the shaft end part 16, the number of parts is not increased.
As a result, it is possible to prevent the center deviation between the shaft portion of the camshaft 10 where the plurality of cam pieces 20 are disposed and the shaft portion including the # 1 journal portion and the occurrence of a phase shift in the circumferential direction. It is also effective in reducing cost and weight.

  Further, in the first embodiment, the annular end projection 16 corresponding to the center hole 17 of the shaft end component 16 is integrally formed on the end surface of the flange 11 of the camshaft 10 so that the shaft end component 16 is the same. Can be attached to the center stably.

In addition, this invention is not limited to the said Example 1 and 2, In the range which does not deviate from the summary of this invention, it can implement with a various form.
For example, as shown in FIGS. 8 and 9, the end tube portion of the metal pipe member 110a constituting the camshaft 10a is plastically processed into a large-diameter disk shape as compared with the first embodiment, and the large-diameter portion. After forming 111b, the large-diameter portion 111b is plastically deformed into a cylindrical shape by drawing to form the cylindrical portion 111c, and then, as shown in FIG. 9, the tip portion 111d of the cylindrical portion 111c is bent to form a flange. 111a may be formed.
In this case, the apparent thickness dimension t of the flange 111a can be made larger than the thickness dimension of the metal pipe material 110.
However, since it may be difficult to form a fitting projection on the end surface of the flange 111a, the flange 111a is formed with a knock pin hole into which the knock pin 13a is driven, and the shaft end component is prevented from rotating. A pin hole into which an interlocking pin 19a for connecting so as to be able to transmit torque is formed.

It is a longitudinal cross-sectional view which shows the camshaft apparatus which concerns on Example 1 of this invention. It is a longitudinal cross-sectional view which similarly shows the metal pipe material which forms a cam shaft. It is a longitudinal cross-sectional view which shows the initial state in which the end cylinder part of the end of a metal pipe material is similarly plastically deformed radially outward. Similarly, it is a longitudinal cross-sectional view showing an intermediate state in which the end tube portion of the metal pipe material is plastically deformed radially outward. It is a longitudinal cross-sectional view which shows the state in which the flange was similarly formed by the end cylinder part of a metal pipe material. It is a longitudinal cross-sectional view which shows the state by which the fitting convex part was similarly formed in the end surface of a flange body. It is explanatory drawing which shows the state by which a rolling bearing is similarly assembled | attached to the axial part corresponding to the # 1 journal part of a camshaft. In another embodiment of the present invention, the end tube portion of the metal pipe material constituting the camshaft is plastically deformed into a disk shape by plastic working, and is then plastically deformed into a cylindrical shape by drawing. It is a longitudinal cross-sectional view shown. It is a longitudinal cross-sectional view which shows the state which bent the front-end | tip part of the cylindrical plastic deformation part of a metal pipe material similarly, and formed the flange. It is a longitudinal cross-sectional view which shows the conventional camshaft apparatus.

Explanation of symbols

DESCRIPTION OF SYMBOLS 10 Camshaft 11 Flange 12 Knock pin hole 13 Knock pin 16 Shaft end part 31 Rolling bearing 32 Outer ring 33 Inner ring 34 Rolling element 110 Metal pipe material 111a Flange

Claims (2)

A camshaft, a plurality of cam pieces arranged in the axial direction of the outer peripheral surface of the camshaft, and a rolling bearing arranged on an outer peripheral surface near one end of the camshaft, and an end-of-shaft component is provided at an end of the camshaft. A camshaft device to be attached,
The camshaft is formed of a metal pipe material,
At one end of the camshaft, a flange is formed by plastically deforming an end tube portion extending in a radial direction from the end face of the metal pipe material outward in the radial direction,
A camshaft bearing device, wherein a knock pin for positioning and attaching the shaft end component to a predetermined position of the flange is driven. The camshaft device according to claim 1,
A camshaft device characterized in that a fitting convex portion into which a center hole of a shaft end component is fitted is integrally formed on an end surface of the flange.

Images