JPH0331470Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention is applicable to the case where a spring holder of a spring for an intake valve or an exhaust valve of an internal combustion engine is removably fixed to a stem of the intake valve or exhaust valve. The present invention relates to an apparatus for manufacturing a valve holder used for this fixing.

[Problems with conventional technology]

Generally, in order to removably fix a spring holder of a spring for an intake valve or exhaust valve of an internal combustion engine to a stem of the intake valve or exhaust valve, first
It is well known that two semi-cylindrical valve sockets 1 are used, which are made by dividing a cylindrical sleeve into two on the left and right sides with the axis line in between, as shown in Figs. 1 has a protrusion 2 integrally formed on its inner circumferential surface that extends in a direction perpendicular to the axis of the valve holder 1, so that when the valve holder 1 is fitted onto a stem 3 of an intake valve or an exhaust valve, the ridge 2 , which is adapted to fit into and engage with the annular groove 4 in the stem 3, while its outer circumferential surface is formed into a thicker tapered surface toward the tip of the stem so that it can be fitted into the spring receiver. It is.

Japanese Utility Model Publication No. 52-12012 as a prior art regarding this valve cotter has chamfers on both ends of the protrusion 2 of the valve cotter 1, that is, on the portions of the ridge 2 located on the left and right divided end faces 5, 5 of the valve cotter 1. It is proposed that by providing the portions 6, 6, the protrusion 2 can be reliably and easily fitted into the annular groove 4 of the stem 3.

The present invention provides an apparatus that can inexpensively manufacture the valve socket 1 having the chamfered portions 6, 6 at both ends of the protrusion 2.

That is, this type of valve cotter uses a strip-shaped material as its raw material, and the cross-section of the strip-shaped material 11 has an irregular cross section that is trapezoidal to match the longitudinal cross-sectional shape of the valve cotter 1, as shown in FIG. At the same time, a protruding strip 12 corresponding to the protruding strip 2 in the valve holder 1 is integrally formed on one side of the strip material 11 so as to extend in the longitudinal direction of the strip material 11. It is manufactured by cutting a band-shaped material 11 with an irregular cross section to an appropriate length (L), press-molding it into a semicircular shape with the protruding strips 12 inside, and then cutting off the excess tabs. It is.

And valve cotter 1 manufactured in this way
When providing the chamfered portions 6, 6 at both ends of the protrusion 2, forming the chamfered portions 6, 6 by cutting one by one for each valve socket 1 requires a large amount of processing time. Since this is necessary, the cost is high, and by providing a projection on the inner mold during the press molding, the chamfered portions 6, 6 are formed on the protrusion 2 at the same time as the press molding. As a result, the shape of the inner mold becomes complicated, which makes the inner mold more likely to be chipped, and the durability of the inner mold decreases, which also increases costs.

The present invention provides chamfered portions at both ends of the protrusion in the valve cotter, and the chamfered portions are
The above-mentioned problem is solved by forming the material in a state before the press molding.

[Means for solving problems]

Therefore, the present invention provides a valve cotter manufacturing apparatus equipped with a press molding section for press-molding into a valve cotter a material piece of an appropriate length cut from a strip material with a protruding strip and irregular cross section that is transferred in the longitudinal direction. V-shaped notches are carved in the protruding strips of the strip material or material piece at intervals equal to the circumferential length of the valve cotter at the front side in the supply direction of the strip material to the press molding section. It is configured with a punch.

[Functions and effects of the idea]

In this way, before supplying the strip-like material with the irregular cross section with protruding stripes to the press molding section, V-shaped notches are made in the protruding strips of the strip-shaped material using a punch at intervals of the length in the circumferential direction of the valve socket. If this is carved, the strip material will be cut at the position of this V-shaped notch, so that chamfered portions will be automatically formed at both ends of the protrusion on the valve holder after press molding by the V-shaped notch. will be formed.

That is, in the present invention, the chamfered portions at both ends of the protruding ridges in the valve cotter are formed at the stage of forming a strip or a piece of material, so after the valve cotter is press-molded, both ends of the ridges are cut. By applying this, it is possible to omit the step of providing each chamfered portion, and the punch for carving the V-shaped notch in the protruding strip of the strip material or material piece can be used with the mold in the press molding section. The punch is a separate piece, which does not complicate the shape of the inner mold in the press molding part, and the punch is exclusively made of V.
Since it is only necessary to carve the shape notches, its durability is high.

Therefore, according to the present invention, it is possible to significantly reduce the cost of manufacturing a valve holder from a strip-shaped material, and the valve holder can be manufactured at a low cost.

〔Example〕

Hereinafter, an embodiment of the present invention will be described with reference to the drawings. In the drawings, reference numeral 20 denotes a press molding part, and the press molding part 20 includes an outer mold 20a having a semicircular recess on the lower surface, and a An inner mold 20b that fits into a semicircular recess, and cutters 2 located on both left and right sides of the lower surface of the inner mold 20b.
0c and 20d, these outer molds 2
When 0a moves downward toward the inner mold 20b,
Both cutters 20c and 20d are configured to move inward, respectively.

A band-shaped material 11 having an irregular cross section and having a protruding strip 12 integrally formed on one side is placed in the press molding section 20.
When feeding intermittently at intervals of a length (L) that is longer than the length () in the circumferential direction of the valve cutter 1 by an appropriate dimension, the cutter mechanism 21 cuts a length (L) of material from the strip material 11. Piece 1
1a is cut, and this material piece 11a is inserted into the outer mold 20a and the inner mold 20 in the press molding section 20.
b, and by the downward movement of the outer mold 20a, press molding is performed as shown in FIG. 6, and then,
By each of the cutters 20c and 20d moving inward, the extra tabs 11a' and 11a' protruding from the outer mold 20a are cut off as shown in FIG. 7 to form the valve cutter 1.

A pair of upper and lower headers 22 and 23 that move toward each other with the strip material 11 in between is disposed at the front side of the press molding section 20 in the supply direction of the strip material 11. 22,
23, the protruding strips 12 on the strip material 11
Two punches 24 each having a protrusion 25 with a V-shaped cross section extending in a direction perpendicular to the longitudinal direction of the strip material 11 are attached to the upper surface of the header 23 on the side opposite to the header 23 . the interval,
The dimension is set to be equal to the length (l) of the valve socket 1 in the circumferential direction.

Then, when both the headers 22 and 23 move toward the protruding strip 12 on the strip material 11,
V-shaped notches 26 are formed by the V-shaped protrusions 25 on both punches 24, 24 at intervals equal to the circumferential length () of the valve socket 1.

Therefore, by setting the center of this V-shaped notch 26 to be located at the cutting position by the cutter cutters 20c and 20d during press molding in the press molding section 20, the protrusion on the valve cutter 1 after press molding is removed. Chamfered portions 4, 4 by the V-shaped notch 26 are automatically formed on both ends of the cylindrical portion 2.

In the above embodiment, the V-shaped notches 26 were carved in the protruding strips 12 of the strip material 11, but the V-shaped notches 26 were carved on the protruding strips 12 after cutting from the strip material 11. Piece 11a
It is also possible to engrave it at the stage of .

In addition, when attaching both punches 24 for carving the V-shaped notch 26 to the header 23 with bolts 27, the bolt holes 28 in both punches 24 are replaced with long holes extending in the longitudinal direction of the strip material 11. If configured as shown in FIG.
It can be easily set to be located at the cutting position according to 0d.

[Brief explanation of the drawing]

Fig. 1 is a perspective view of the valve socket and stem, Fig. 2 is a cross-sectional view taken from the side in Fig. 1, Fig. 3 is a cross-sectional view taken from the side shown in Fig. 1, and Fig. 4 is a perspective view of the band-shaped material.
Fig. 5 is a diagram showing an embodiment of the present invention, Fig. 6 and Fig. 7 are diagrams showing the operating state of press molding, Fig. 8 is a perspective view of the band-shaped material in the present invention, and Fig. 9 is a diagram in the present invention. FIG. 10 is a cross-sectional view of the punch for forming a V-shaped notch, and FIG. 10 is a plan view of FIG. 9. DESCRIPTION OF SYMBOLS 1... Valve cotter, 2... Projection, 3... Stem, 6... Chamfered part, 11... Band-shaped material with irregular cross section, 12... Projection, 20... Press molded part, 2
2, 23...Hetsuda, 24...Punch, 25...
V-shaped protrusion, 26...V-shaped notch.

Claims (1)

[Scope of utility model registration request] In a valve cotter manufacturing apparatus, which is equipped with a press molding section for press-molding a material piece of an appropriate length cut from a strip material having an irregular cross section with protrusions that is transferred in the longitudinal direction into a valve cotter, A punch is provided on the front side of the strip-shaped material in the supply direction, and the punch is configured to carve V-shaped notches on the protruding strips of the strip-shaped material or piece of material at intervals equal to the circumferential length of the valve cotter. A manufacturing device for valve combs for internal combustion engines.