JPH0527727Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a forced rotation mechanism of a cam gear, and particularly to an improvement of a forced rotation mechanism of a cam gear in a power assist system.

[Conventional technology]

Generally, in a power assist system, a drive gear that transmits the rotation of the motor and a cam gear that has a cam are engaged when switching modes, but the engagement between the drive gear and cam gear is usually achieved by using a resilient force such as a spring. However, in order to further ensure smooth engagement, a cam gear forced rotation mechanism is used in which when the cam gear is unlocked, the cam gear is forcibly rotated by the action of the play arm and fed into the drive gear. It is being The forced rotation mechanism of this cam gear is shown in Figures 3 to 4.
What is shown in the figure is known. That is, FIG. 3 is a schematic plan view showing the main parts of a conventional forced rotation mechanism of a cam gear. In the figure, 1 has tooth parts 2, 2... formed on the outer periphery, and a cam (inclined part) 3 in a part. This is the formed cam gear. In addition, 4 in the figure is a play arm rotatably supported by a shaft 5 at approximately the center thereof,
One end of this play arm 4 is fixed to a pin 6a of a solenoid 6, and a round pin 7 that engages with a triangular stopper 8 protruding from the inner periphery of the cam gear 1 protrudes from the other end. It is set up. Here, in order to forcibly rotate the cam gear 1 described above and mesh it smoothly with the drive gear (not shown), the solenoid 6 is activated and the pin 6a is sucked in the direction of arrow A in the figure. The play arm 4 fixed to the pin 6a of the solenoid 6 is connected to the shaft 5.
The other end is swung in the direction of arrow B. Due to this rotational movement of the play arm 4, the round pin 7 protruding from the other end of the play arm 4 is removed from the stopper 8, and the arrow C shown in FIG.
The lock state is released by shifting in the direction, and at the same time it hits the inclined surface of the cam 3, and the cam 3
By pushing in the direction of arrow D, the cam gear 1 is forcibly rotated in the direction of arrow D.

[Problems to be solved by the invention] However, according to this conventional cam gear forced rotation mechanism, in order to obtain a sufficient driving force for the cam 3, that is, a force for rotating the cam gear 1 to a predetermined angle, Since the stroke of the solenoid 6 must be increased, the voltage applied to the solenoid 6 must be increased, which is disadvantageous in terms of power saving.

Therefore, the present invention was made by focusing on the problems of the conventional technology, and it solves the problems and saves power by eliminating the need to make the stroke of the solenoid particularly large. It is an object of the present invention to provide a forced rotation mechanism for a cam gear that can obtain a sufficient rotation angle of the cam gear with a simple mechanical structure without requiring any modification.

[Means for solving problems]

In order to achieve this purpose, the cam gear forced rotation mechanism according to the present invention has one end fixed to a solenoid pin, and the other end of the play arm, which is rotatably supported, engaged with a stopper of the cam gear. In the forced rotation mechanism of the cam gear, the mechanism includes a protruding pin that locks the cam gear and, when the lock is released, pushes a cam formed on the cam gear to forcibly rotate the cam gear. The pin is disposed near the center, and the pin has an elongated cross-sectional shape with one end that engages the stopper and the other end that presses the cam, and the pin is located near the center of rotation of the play arm. It is characterized in that the dimension from the center of rotation of the play arm to the other end of the pin is larger than the dimension from the one end.

[Effect]

As described above, the pin protruding from the play arm has an elongated cross-sectional shape with one end that engages with the stopper and the other end that presses the cam, and the dimension from the center of rotation of the play arm to the one end of the pin. Because the dimension from the center of rotation of the play arm to the other end of the pin is larger than that of the play arm, and the cam of the cam gear is placed closer to the center of the cam gear than the stopper, the part where the pin contacts the cam is larger than that of the round pin. Unlike the conventional case, the play arm is moved further outward from the rotation center of the play arm, so the movement is sufficient to give a sufficient rotation angle to the cam gear without particularly increasing the stroke of the solenoid or making any changes to the cam gear. You can get the amount.

〔Example〕

Next, an example of the implementation of the present invention will be described in detail with reference to FIGS. 1 and 2.

FIG. 1 is a plan view of a main part showing a forced rotation mechanism of a cam gear embodying the present invention, and numeral 10 in the figure indicates the cam gear. This cam gear 10 has teeth 11, 11... formed on its outer periphery, and a tapered surface 12 in some parts.
A cam 12 is formed, and a triangular stopper 13 is protruded from the inner periphery.

On the other hand, reference numeral 14 in the figure is a play arm whose one end is fixed to a solenoid pin (not shown) and rotatably supported by a shaft 15 at a substantially central position thereof.
On the other end (free end) side of the play arm 14, an elongated round pin 16 having an elongated cross section that engages with the stopper 13 of the cam gear 10 to lock the cam gear 10 is provided.

Here, when the cam gear 10 described above is engaged with the drive gear, when a solenoid (not shown) is activated to attract the solenoid pin, the play arm 14 is moved around the shaft 15 as a fulcrum because one end is fixed to the solenoid pin. It rotates and swings the other end (free end) in the direction of the arrow shown in FIG. Due to this rotation of the play arm 14, the long round pin 16 is smoothly removed from the stopper 13 because the stopper 13 is triangular, and the locked state of the cam gear 10 is released. At the same time as this lock is released, the elongated round pin 16 protruding from the play arm 14 is connected to the cam 12 formed on the cam gear 10.
Press the tapered surface 12a of the cam gear 10 forcibly.
Rotate. In addition, in the case of the present invention, the cam gear 10
The cam 12 is arranged closer to the center of the cam gear 10 than the stopper 13, and the long round pin 16 has one end that engages with the stopper 13 and the other end that presses the cam 12. Similarly, the distance from the rotation center of the play arm 14 to one end of the long round pin 16 is
Since the dimension to the other end of the play arm 14 is larger, when the play arm 14 rotates and the oblong pin 16 pushes the tapered surface 12a of the cam 12, it will be located at the center of rotation of the play arm 14. On the other hand, the outer part comes into contact with the tapered surface 12a of the cam 12,
Even if the stroke of the solenoid 6 is the same, a larger amount of movement can be obtained than when using a round pin.

[Effect of idea]

As described above, according to the forced rotation mechanism of the cam gear according to the present invention, the pin protruding from the play arm has an elongated cross-sectional shape having one end that engages with the stopper and the other end that presses the cam. The dimension from the center of rotation of the play arm to the other end of the pin is also larger than the dimension from the center of rotation of the arm to one end of the pin, and the cam of the cam gear is placed closer to the center of the cam gear than the stopper. ,
The position where the pin makes contact with the cam of the cam gear is further outward from the center of rotation of the play arm than a round pin, resulting in a larger amount of movement even if the solenoid stroke is the same. , it is possible to give a sufficient rotation angle to the cam gear by mechanical operation without making any changes to the structure of the cam gear.

[Brief explanation of the drawing]

Fig. 1 shows the main parts of the forced rotation mechanism of the cam gear according to the present invention, and is a schematic plan view showing the locked state of the cam gear, Fig. 2 is a schematic plan view showing the forced rotation state of the cam gear, and Fig. 3 is a conventional one. As an example, FIG. 4 is a schematic plan view showing the locked state of the cam gear, and FIG. 4 is a schematic plan view of the main part showing the movement of the pin protruding from the play arm. 6... Solenoid, 6a... Solenoid pin,
10... Cam gear, 12... Cam, 12a... Tapered surface, 13... Stopper, 14... Play arm, 15... Shaft, 16... Oblong pin.

Claims (1)

[Scope of utility model registration request] One end is fixed to a solenoid, and the other end of the play arm, which is rotatably supported, engages with a stopper of a cam gear to lock the cam gear, and when the lock is released, the cam formed on the cam gear is pushed. In a cam gear forced rotation mechanism in which a pin for forcibly rotating the cam gear is protruded, the cam of the cam gear is arranged closer to the center of the cam gear than the stopper, and the pin has one end that engages with the stopper. and the other end that presses the cam, and the distance from the rotation center of the play arm to the other end of the pin is smaller than the distance from the rotation center of the play arm to the one end of the pin. A cam gear forced rotation mechanism characterized by a large dimension up to the end.