JP2525200Y2 - Shaft fixing mechanism - Google Patents

Description

[Detailed description of the invention]

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a shaft fixing mechanism for mounting a rotating body such as a gear or a cam on a rotating shaft.

[0002]

2. Description of the Related Art FIG. 4 is an exploded perspective view of a conventional gear shaft fixing mechanism disclosed in Japanese Utility Model Laid-Open Publication No. 1-60068. In the drawing, 1 is a rotating shaft, 2 is a stop pin inserted into a through hole 3 formed in the rotating shaft 1, and 4 is a predetermined pin extending from the through hole 3 around the rotating shaft 1 on the shaft end side of the rotating shaft 1. The circumferential groove 5 provided at the dimensional position is a gear, and has a central hole 5a into which the rotating shaft 1 is inserted and a concave groove 5b into the end face of the hub portion which crosses the central hole 5a and into which the stop pin 2 enters. Reference numeral 6 denotes an E-shaped stop ring, which is fitted in the circumferential groove 4 and has a rotating shaft 1 of the gear 5.
It is responsible for positioning and retaining.

[0003] In the conventional gear shaft fixing mechanism configured as described above, the assembling procedure is as follows. First, the stop pin 2 is softly pressed into the through hole 3, and the gear 5 is inserted into the rotary shaft 1.
The groove 5b and the stop pin 2 are brought into contact with each other, and the E-shaped stop ring 6 is fitted into the peripheral groove 4 to complete the process. And
During operation, the rotational force of the rotating shaft 1 is transmitted to the gear 5 from the groove 5 b via the stop pin 2.

[0004]

In the above-described gear shaft fixing mechanism, the fitting of the E-shaped stop ring 6 into the circumferential groove 4 must be inserted along the end face of the gear 5, making the operation difficult. Met. Further, since the stop pin 2 receives the impact at the time of starting the forward rotation and the reverse rotation of the gear 5, the soft press-fitting of the stop pin 2 is loosened and the stop pin 2 comes off . Also the gear
E-stop ring 6 must be removed when removing 5
However, there was a problem that removal was difficult .

[0005] This invention has been made to solve the above problems, to improve the assembly of the shaft fixing mechanism of the rotary member such as a gear or a cam, detachment of the stop pin 2 rather name also It is another object of the present invention to provide a gear shaft fixing mechanism that can be easily removed .

[0006]

A shaft fixing mechanism according to the present invention has a circumferential groove provided at a position of a predetermined size from a stop pin erected on a rotary shaft, and a hub end surface of one of the rotating members. A concave groove slightly longer than the provided stop pin, and the other hub of the rotating body is axially projected at the tip of an arm piece formed by dividing the other hub in the axial direction of the rotating shaft, and is urged in the axial direction. And a claw engaged with the circumferential groove.

[0007]

In the shaft fixing mechanism according to the present invention, the pawl engaged with the circumferential groove and urged in the axial direction holds the engagement between the concave groove and the stop pin, serves to prevent the rotating body from coming off, and is slightly smaller than the stop pin. The long end of the groove prevents the stop pin from falling off.

[0008]

[Embodiment 1] FIG. 1 is an exploded perspective view of a gear shaft fixing mechanism showing one embodiment of the present invention, and FIG. 2 is a sectional view of the shaft fixing mechanism. In the figure, reference numerals 1 to 4 are the same as those described in the above conventional example. 1a is a chamfer given to the shaft end face of the rotating shaft 1.
Recently, gears and cams are often made of synthetic resin in view of reduction of rotation noise and manufacturing cost. Reference numeral 7 denotes a rotating body formed of elastic synthetic resin (for example, polyacetal resin). The groove 7b into which the stop pin 2 is inserted into the end face of one hub 7a of the gear 7
Are provided, and both ends of the concave groove 7b are closed by the extension of the hub 7a serving as a wall. Reference numeral 7d denotes an arm piece obtained by dividing a part of the other hub 7c in the axial direction of the rotary shaft 1, and a claw 7e is provided at a tip end thereof in the axial direction of the rotary shaft 1. The dimensions of the claw 7e and the concave groove 7b are provided so as to match the dimensions of the stop pin 2 and the peripheral groove 4. The claw 7e is urged in the axial direction of the rotating shaft 1 by the elasticity of the arm piece 7d. 7f is the tip of the arm piece 7d, that is, the claw 7
e, extending further in the axial direction of the rotating shaft and projecting.
It is a projection for removal provided.

The assembling procedure of the gear shaft fixing mechanism constructed as described above will be described. First, the stop pin 2 is softly press-fitted into the through hole 3, the gear 7 is inserted into the rotary shaft 1 from the hub 7a side, and the concave groove is formed. The gear 7 is pushed in at a position where the stop pin 2 coincides with the stop pin 7b. At this time, the tip of the claw 7e hits the end face of the rotating shaft 1, but when the gear 7 is further pushed in, the claw 7e climbs the slope of the chamfer 1a.
Engages with the circumferential groove 4 to prevent the gear 7 from coming off. Further, dropping of the stop pin 2 due to loosening of the soft press-fit of the stop pin 2 due to the impact at the time of starting the forward rotation or the reverse rotation of the gear 7 is prevented by the both end walls of the concave groove 7b. Next, how to remove the gear
Then, the protrusion 7f is pulled up, so that the claw 7e is
b, and pull out the gear 7 from the rotating shaft 1.

Embodiment 2 FIG. FIG. 3 shows a gear shaft fixing mechanism using a cam instead of the gear 7 in the shaft fixing mechanism. In the figure, 1-4, 7a
7e are the same as those described in the first embodiment. Reference numeral 8 denotes a cam as a rotating body. In this configuration, by engaging the stop pin 2 with the concave groove 7b, the rotational phase angles of the rotating shaft 1 and the cam 8 can be surely matched.

In the above description, the stop pin 2 inserted through the through hole 3 formed in the rotary shaft 1 has been described.
The same effect can be obtained even when the hole 3 is a blind hole and the stop pin 2 is only one side.

[0012]

According to the present invention, as described above, the peripheral groove provided at a position of a predetermined size from the stop pin erected on the rotating shaft and the hub end face of one of the rotating members are provided. A concave groove slightly longer than the stop pin, an arm piece formed by dividing the other hub of the rotated body in the axial direction of the rotation shaft, and an arm piece protruding in the axial direction at the tip of this arm piece.
And a pawl which is biased in the axial direction engages in the circumferential groove, this
Along the tip of the claw, it extends in the axial direction and
By providing the removal projection , it is possible to connect the rotating body to the rotating shaft by a simple operation of pushing and inserting the same , and therefore , the mounting of the rotating body to the rotating shaft is easy, and the assemblability is improved.
Falling off of the stop pins rather than name, at the same time, the claw of the arm piece tip
Since the projection for removal has been further extended to the tip of
It can be easily removed using the projection, and the above mounting operation
Combined with ease of attachment and detachment.
It has a loose effect.

[Brief description of the drawings]

FIG. 1 is an exploded perspective view of a gear shaft fixing mechanism showing one embodiment of the present invention.

FIG. 2 is a sectional view of the shaft fixing mechanism according to the embodiment of the present invention;

FIG. 3 is an exploded perspective view of a shaft fixing mechanism according to another embodiment of the present invention.

FIG. 4 is an exploded perspective view of a conventional gear shaft fixing mechanism.

[Explanation of symbols]

DESCRIPTION OF SYMBOLS 1 Rotation shaft 2 Stop pin 4 Peripheral groove 7 Gear 7b Depressed groove 7c Hub 7d Arm piece 7e Claw 7f Projection 8 Cam

Claims (1)

(57) [Scope of request for utility model registration] 1. A shaft fixing mechanism for mounting a rotating body such as a gear or a cam on a rotating shaft, a stop pin erected on the rotating shaft, and provided on a periphery of the rotating shaft at a position of a predetermined dimension from the stop pin. A rotated body having a center hole inserted into the rotary shaft, a groove provided on one end face of one of the hubs and slightly longer than the stop pin, and the other hub of the rotated body. An arm piece having elasticity formed by dividing a part in the axial direction of the rotating shaft, and a tip end of the arm piece is provided so as to protrude in the axial direction of the rotating shaft.
The claw engaging with the circumferential groove and the claw at the tip of the arm piece
Extend further in the axial direction of the rotating shaft and project
A shaft fixing mechanism comprising a detachable projection .