JPS6263057A - Cam surface lapping device - Google Patents

Abstract

PURPOSE:To provide the concentrated polishing action under the point or line contact condition by urging a projection arcuate urging body of a polishing table against a cam surface to lap the cam surface with the rotation of a cam shaft and the reciprocation of the polishing table. CONSTITUTION:A cam shaft 1 is supported by both centers and rotated by driving a spindle, while a slide table 11 is reciprocated. Then, since a polishing table 27 is pressed against a cam surface 2 of the cam shaft 1 by a spring 24, lapping is carried out by the composite motion of the circumferential motion of the cam surface 2 due to the rotation of the cam surface 2 and the widthwise motion of the polishing table 27 due to the lateral motion of the slide table 11. And since the polishing table 27 has a projection arcuate portion along an urging body 22, it makes point or line contact with the cam surface 2 to polish effectively projections remaining on the cam surface 2.

Description

Detailed Description of the Invention (Industrial Application Field) The present invention is a lapping device for finishing the cam surface of a camshaft of an internal combustion engine, and is a versatile device that is not limited by the size or shape of the cam. Regarding.

(Prior Art) Conventional camshaft lapping devices are specialized machines for Okawa production, and rely on manual work for prototypes, small-volume production models, and the like.

(Problems to be Solved by the Invention) The present invention aims to provide a device that can be used for prototypes and small-volume production products without being restricted by the size and shape of the cam, and can efficiently wrap a smooth cam surface. purpose.

(Means for Solving the Problems) The present invention provides a drive device that supports and rotates a camshaft, an enclosing table that is drive-guided to reciprocate on a base in the axial direction of the camshaft, and a sliding table that rotates while supporting a camshaft. A plurality of lever arms, one end of which is pivotally attached to the movable table and a convex arc-shaped pressing portion on which the abrasive member is held on the other end, are formed, and the surface of the convex arc-shaped portion of the lever arm The desired purpose is achieved by including an elastic member that presses the abrasive member against the cam surface.

(Function) The abrasive tape is pressed against the cam surface of the camshaft by a convex arc-shaped suppressor, and is wrapped by the rotation of the camshaft and the horizontal reciprocation of the abrasive tape. Since the abrasive tape has a convex arc shape, it contacts the protrusions on the cam surface in a point or line contact state, so that the abrasive action is concentrated and the protrusions are easily smoothed.

(Example) In the figure, (1) is a camshaft to be wrapped, and (2), (2)... are cam surfaces to be wrapped. The camshaft (1) has both ends centered (3), <4
), and is rotationally driven by a main shaft (5) integral with the center (3) and a locking tool (6). A gear (7) is fixed to the main shaft (5), and a gear (9) is pivotally supported on the base (8).
) to drive. A cam +10 is fixed to the gear (9),
A follower (2) integrated with the activity table at is driven to reciprocate the activity table ('1D) in the axial direction of the camshaft (1).

The sliding table aD is mounted on the base (8) with support rollers a
@, 6Φ..., holding rollers a9, (I5)..., guide rollers ne, tie..., and are supported so as to be able to reciprocate in the lateral direction. There are frames 071. at both left and right ends of the sliding table at. ■ is erected, a support shaft (19) is installed on this, a bearing ■ fixed to one end of the lever arm ■ is pivoted, and a convex arc-shaped pressing body is fixed to the other end of the lever arm ■. A rubber plate is glued to its outer surface.There is a compression spring [phase] between the middle lower surface of the lever arm ■ and the sliding table 0υ, which presses the lever arm ■ upward. ing.

A support shaft (2) equipped with a ratchet wheel (2) is detachably supported on the frame (17) and G8, and a ratchet (25a) is engaged with the ratchet wheel (2). An abrasive tape glue is fitted onto the support shaft (2), and rotation in the tape feeding direction (2) is prevented by a ratchet (25a). ■ is a tape guide, ■ is a clip, and these are used to stretch the tape ■ pulled out from the reel ■ onto the surface of the pressing body ■. A return spring is used to press the sliding base ('Ii) toward the cam (11) and return it to the cam 0C1 side.

As shown in Figure 2, move the camshaft (1) to the center (3), (
4) and drives the main shaft (5)', the locking tool (6)
) rotates the camshaft (1), and at the same time the gear (
7) and (9), the cam 00 rotates and pushes the follower (121) of the sliding table at, and the slope of the cam and the return spring ■
By 1! ! ! Make the table reciprocate for the first time. At this time, since the abrasive tape is pressed against the cam surface (2) of the camshaft (1) by the spring [phase], the circumferential movement of the cam surface due to the rotation of the cam surface (2) and the sliding Lapping is performed by a combined movement of the horizontal movement of the moving table (In) and the widthwise movement of the abrasive tape (■). Therefore, it makes point contact or line contact with the cam surface (2), and has an excellent polishing effect on the protrusions left on the cam surface.

This polishing action will be explained with reference to FIGS. 4 and 5.

FIG. 4 shows the present invention. In contrast to the linear protrusions (2) and (2) remaining at intervals on the cam surface (2), as shown in (a) of the same figure, the abrasive tape has an arcuate shape. Therefore, only one of them (■) is brought into line contact and polished, and as the camshaft rotates, the protrusion ω also begins to come into contact, but the protrusion (■) gradually moves away, and then only the protrusion (■) is polished. , the cam surface (
2) is a gentle surface. On the flat parts of the cam surface (2) other than the projections such as ■ and ■, the abrasive tape is in surface contact due to the interaction between the elasticity of the rubber plate ■ on the outer surface of the pressing body ■ and the flat parts. As a result, the abrasive action decreases, but
When contacting one of the protrusions, for example, ■, the protrusion rides on the protrusion (■) and forms a line contact, the contact pressure increases, the amount of polishing increases, and the protrusion is quickly smoothed.

On the other hand, if the pressing body has a flat or concave surface, as shown in FIG.
As shown in a), the polishing tape contacts two protrusions (1) and (2), and actually contacts many protrusions, resulting in a state close to surface contact, and the abrasive action is small and smoothing is difficult. For example, in FIG. 5, since the protrusions (1) and (2) do not come into contact with the opposing surfaces, serrated protrusions are left as shown in FIG. 5(b). Therefore, when using such a cam surface,
This results in faster wear of the cam follower.

By providing as many units as the number of cam surfaces (2) of the camshaft, each consisting of a lever arm (2), an abrasive tape (2), etc., the lapping work can be completed in one set. When the abrasive tape has deteriorated, remove the ratchet (25a) from the ratchet foil ■, pull out the abrasive tape from the reel, and with the new abrasive surface in the working position, attach the tip to the tip of the cutting machine clip ■ to the tip of the lever arm. Fix it, take up the slack in the tape, and attach the ratchet foil ■ and ratchet (25
Engage a) and move on to the next wrapping operation. Even if the size and shape of the cam surface to be wrapped differ, the above-mentioned effect does not change, so it can be used with many types of camshafts and is versatile.

(Effects of the Invention) In the present invention, since the working surface of the abrasive tape has a convex arc shape, it exerts a strong abrasive action on the protrusions left on the cam surface in a point or line contact state. It has a high ability to polish and smooth protrusions.The polishing effect is the same even if the size and shape of the cam is different, so it is versatile.

[Brief explanation of the drawing]

Fig. 1 is a front view showing the main parts of the embodiment of the present invention, Fig. 2 is a plan view, Fig. 3 is a side view showing the relationship between the base and the sliding table, and Figs. 4 and 5 are the polishing action. FIG. (1)...Camshaft■...Lever arm■...Pushing body■...Abrasive tape old Z6 )

Claims (1)

[Claims] A driving device that supports and rotates the camshaft, a sliding table that is drive-guided to reciprocate in the axial direction of the camshaft on a base, one end of which is pivotally attached to the sliding table, and the other A plurality of lever arms each having a convex arc-shaped pressing portion on the surface of which the abrasive member is held, and an elastic member that presses the abrasive member on the surface of the convex arc-shaped portion of the lever arm against the cam surface. A cam surface wrapping device featuring: