JP2532022Y2 - Camshaft - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an improvement of a camshaft used as one of components of a transmission. The camshaft of the present invention is, for example, a generator, a lawn mower, a rice transplanter
Alternatively , it is used as one of the components of an engine such as a tractor .

[0002]

2. Description of the Related Art As shown in FIG. 11, a known camshaft a is formed by integrally forming a cam b and a shaft c.
A gear d, a key e, a flyweight f, a flyweight shaft g, a spring h, a spring pin i, and a decomp pin j, which are separate parts, are combined.

[0003]

However, the above-mentioned prior art has a problem that the number of parts is large because the total number of parts is eight, and the number of assembly steps is accordingly large. Also
This camshaft in which the cam b and the shaft c are integrally formed
a is generally formed by a metal such as steel or cast iron.
Therefore, there is a problem that the weight is heavy. I mentioned above
As described above, this kind of camshaft a is used for a rice transplanter or a tractor.
Used in engines of self-propelled agricultural machines such as
And therefore a little bit lighter
That directly contributes to the improvement of engine output.
Can be.

[0004]

SUMMARY OF THE INVENTION In view of the above, the present invention has been devised to solve the above-mentioned problems in the prior art, and in order to achieve this object, a cam and a shaft are integrated. Gear,
The spring hook and the flyweight stopper are integrally formed, and the gear is
Fly weight shaft insert for rotatably mounting the shaft
Form an inlet hole and open the fly weight shaft insertion hole.
A metal washer is integrated with the periphery of the mouth by insert molding
I decided to.

[0005]

According to the camshaft of the present invention having the above configuration, it is possible to reduce the number of parts from eight to five (camshaft, flyweight, flyweight shaft, spring and decomp pin) in the prior art. is there.

When integrally molding a plurality of parts with a resin in the prior art, the following points must be considered.

[0007]  Fly weight movement at a fixed position
Conventionally, the stopper function to stop the gear
A concave portion is formed on the surface, and the outer peripheral wall surface of the concave portion (the rim of the gear) is formed.
By contacting the fly weight with the inner peripheral surface of the part)
I've been going. However, in the case of molding with resin,
To improve the releasability of the molded product, the end face of the gear
It is not preferable to form a concave portion on the
Need to be formed into a convex shape. In view of this point, the present invention
In particular, a fly weight stopper is provided,
By contacting the fly weight with the light stopper
The fly weight was stopped.The cam and shaft are molded integrally with resin
Weight savings over metal camshafts.
Fly that can follow the fly weight
Flyway into which the weight shaft is rotatably inserted
For the periphery of the opening of the light shaft insertion hole,
Repeated stress is applied with the operation of the gate shaft
Therefore, it is necessary to secure sufficient strength here.
You. In view of this point, in the present invention, in particular, the entire camshaft is
After molding with resin, fly weight shaft
Insert washer with metal washer around the periphery of the insertion hole
A more integrated, mechanically large enough
I decided to secure the strength.

[0008]

BRIEF DESCRIPTION OF THE DRAWINGS FIG.

FIGS. 1 to 7 show an integral molded product formed of phenolic resin. The only exception is the opening of a fly weight shaft insertion hole 9 for rotatably mounting a fly weight shaft 12 described later.
A metal washer 10 is insert-molded at the (periphery of the opening) .

The camshaft shown in FIGS. 1 to 7 has the following configuration. That is, a required number (two in the figure) of the cams 2 and the gears 3 are integrally formed on the shaft 1, and the decompression pin insertion holes 4 are formed obliquely with respect to the center line. The end face 3a of the gear 3 is formed into a flat surface.
a, a spring hook 5 and a fly weight stopper 6 are integrally protruded, and a required number (two in the figure) of fly weight guides 7 are also integrally protruded. As shown in FIG. 6, the spring hook 5 is a projection provided with a disk-shaped flange 5a at the tip.
Hook one end of Fly weight stopper 6
As shown in FIG. The gear 3 has a substantially fan-shaped window hole 8 for preventing spring interference and a flyweight shaft insertion hole 9.

FIG. 8 to FIG. 10 show the molded article having the above structure.
The figure shows a fly weight 11, a fly weight shaft 12, a spring 13 and a decompression pin 14, which are separate parts.

Thus, the camshaft having the above configuration has the following operational effects.

That is, first, the number of parts can be reduced from eight in the above-described conventional technology to five, and the number of assembly steps can be reduced accordingly. It is also advantageous in terms of cost. Further, the fly weight stopper 6 is provided, and the fly weight 11 is stopped by bringing the fly weight 11 into contact with the fly weight stopper 6, so that the end face 3a of the gear 3 is flat even though Accurate operation of the flyweight 11 can be ensured. In addition, cam 2, shaft 1, gear 3, spur
Ring hook 5 and fly weight stopper 6 are made of resin.
Metal camshaft
Weight can be reduced. Therefore the above
So that the camshaft is
When used in self-propelled agricultural machinery engines,
Engine output can be improved by weight reduction
You. Furthermore, after molding the entire camshaft with resin
Metal on the periphery of the opening of the flyweight shaft insertion hole 9
Washer 10 made by insert molding
In here, enough strength can be secured
You. Therefore, although the overall camshaft is lightweight,
Where necessary, a high quality camera with sufficient mechanical strength
A shaft can be provided. Also when assembling
Fly weight shaft insertion hole 9
The shaft 12 is inserted and the tip of the shaft 12 is closed.
In case of squeezing, the opponent is metal washer 1 instead of resin.
Caulking should be performed with relatively strong pressure to reach zero.
And as a result, there is no wobble in the swaged structure
It can be solid.

[0014]

[Effects of the Invention] The present invention has the following effects. That is, first, the cam and the resin of the camshaft which is integrally molded shaft, gears, springs hook and flyweights stopper to decide to integrally molded, parts
The number of parts can be reduced as compared with the related art, and accordingly, the number of assembly steps can be reduced. It is also advantageous in terms of cost. In addition, a fly weight stopper is provided, and the fly weight is stopped by bringing the fly weight into contact with the fly weight stopper. Can be secured. Also, cam,
Shafts, gears, spring hooks and flyweights
Because the topper was molded integrally with resin,
The weight can be reduced more than the camshaft. did
As a result, the camshaft is
Used as one of the components of the engine of a self-propelled agricultural machine
The engine output by increasing the weight of parts.
Can be up. Furthermore, the entire camshaft is made of resin
Around the opening of the flyweight shaft insertion hole
Metal washer was integrated into the part by insert molding
In order to secure enough strength here
You. Therefore, although the overall camshaft is lightweight,
Where necessary, a high quality camera with sufficient mechanical strength
A shaft can be provided. Also when assembling
To the flyweight shaft insertion hole
When caulking the tip of this shaft by inserting the shaft
In addition, the opponent is not a resin but a metal washer
In addition, caulking can be performed with relatively high pressure.
As a result, the caulking structure is firm and stable
It can be.

[Brief description of the drawings]

FIG. 1 is a partially cutaway front view of a camshaft according to an embodiment of the present invention.

FIG. 2 is a left side view of the camshaft.

FIG. 3 is a sectional view taken along line AA in FIG. 1;

FIG. 4 is a sectional view taken along line BB in FIG. 1;

FIG. 5 is a sectional view taken along line CC in FIG. 2;

FIG. 6 is a sectional view taken along line DD in FIG. 3;

FIG. 7 is a sectional view taken along line EE in FIG. 3;

FIG. 8 is a front view showing a state where another part is assembled to the camshaft.

9 is a sectional view taken along line FF in FIG.

FIG. 10 is a sectional view taken along line GG in FIG. 9;

FIG. 11 is an exploded perspective view of a camshaft according to a conventional example.

[Explanation of symbols]

 Reference Signs List 1 shaft 2 cam 3 gear 3a end face 4 decomp pin insertion hole 5 spring hook 5a flange 6 fly weight stopper 7 fly weight guide 8 spring interference prevention window hole 9 fly weight shaft insertion hole 10 washer 11 fly weight 12 fly weight shaft 13 spring 14 Decomp pin

Claims (1)

(57) [Scope of request for utility model registration] A gear (3), a spring hook (5) and a flyweight stopper (6) are integrally formed on a resin camshaft in which a cam (2) and a shaft (1) are integrally formed . A flyweight shaft (12) is attached to the gear (3).
Rotatable flyweight shaft insertion hole
(9) is formed, and the periphery of the opening of the flyweight shaft insertion hole (9) is formed.
And metal washer (10) integrated by insert molding
Camshaft, characterized in that ized.