JP2536053Y2 - Worm gear device for card feed - Google Patents

Description

[Detailed description of the invention] [Industrial application field] The invention is used in the technical field of a card feeder or a printing machine that sends various cards using a small motor, and specifically, The present invention relates to an improvement in a worm gear device that reduces the rotation of a small motor and transmits the rotation to a card feed roller.

[Conventional technology]

FIGS. 4 and 5 show a conventional worm gear device for feeding a card. In the drawings, reference numeral 1 denotes a worm fixed (press-fitted or bonded) to a rotating shaft Ma of a small motor M; The worm wheel and the card feed roller attached to the roller rotation shaft 2 orthogonal to the rotation axis Ma of the motor M
When the worm 1 rotates, the worm wheel 3 meshing with the worm 1 rotates to rotate the roller rotating shaft 2 at a reduced speed. Therefore, the card feed roller 4 attached to the roller rotating shaft 2 rotates in conjunction with The structure is such that the card T inserted between the pressing roller 5 and the pressing roller 5 is fed.

[Problems to be solved by the invention]

According to the worm gear device described above, the card T is determined in advance by transmitting the rotation of the motor M to the card feed roller 4 side to feed the card, while stopping the power supply to the motor M at a certain timing. Stop in position,
The printing stage or the like can be determined. However, if the card T is forcibly pushed between the card feed roller 4 and the pressing roller, the rotation amount after the power supply to the motor M is stopped varies. And the card T cannot be stopped at a predetermined position.

That is, at the time of normal card feeding, when the power supply to the motor M is stopped, the motor M rotates by a fixed amount due to the inertia force, and during the rotation by the inertia from the card feed roller 4 side as shown by an arrow X in FIG. since the thrust load F ₁ acting as a reaction force for rotating the roller 4 in the direction is applied, the normal braking characteristics, is a mechanism which determined by the thrust friction of the motor M within the bearing caused by the thrust load F ₁ I have.

However, as shown in FIG.
Insert the card T during which when pushed in the direction of force arrows Y the is thrust load F ₂ is generated from the card feed roller 4 side in the opposite direction shown in the arrows Z, F ₁ -F ₂
Therefore, the thrust frictional force of the internal bearing of the motor M decreases, and becomes zero when F ₁ = F _{2. In} this state, the rotation amount of the motor M after the power supply is stopped becomes unnecessarily large. There was a problem that the stop position of T was greatly shifted.

When the above-mentioned thrust load becomes F ₁ <F ₂ , the direction of receiving the thrust inside the motor M is reversed, so that the effect of reducing the braking effect is exerted. since F ₂ will increase more strongly when the pushing force of the card T is strong, the variation of the braking effect, i.e., it has become to facilitate the dispersion of the printing position, when the printing machine, the card T There is a problem that printing cannot be performed in a predetermined printing step.

Therefore, the technical problem of the present invention is to determine the card in advance so that the rotation amount of the card feed roller after the power supply to the motor does not become unnecessarily large even when the card is forcibly pushed between the feed rollers. It is an object of the present invention to provide a worm gear device for feeding a card which can stop at a set position.

[Means for solving the problem]

The measures taken in the present invention to solve the above technical problems are as follows.

A worm and a worm gear that mesh with each other are mounted on each rotating shaft of the motor and the card feed roller that intersect at right angles,
When the motor rotates, the card feeding roller is decelerated and rotated by the engagement of the worm and the worm gear, and the card feeding device configured to feed the card inserted between the card feeding roller and the pressing roller. ) The worm is mounted so as to be movable in the axial direction with respect to the rotation axis of the motor.

(2) Between the motor and the worm, the worm is constantly pressed in the direction of the tip of the rotating shaft by receiving the resilient force of the spring, and the tip surface is placed on the receiving plate provided on the axis of the rotating shaft. Provide a worm push that can be pressed against the receiving plate.

[Action]

 The above means works as follows.

The element (1) moves the worm, which meshes with the worm wheel and transmits the rotation of the motor to the card feed roller while reducing the speed, freely in either the direction of the motor or the tip side of the rotating shaft. Make it possible.

The element (2) presses the worm in the direction of the tip of the rotating shaft by the spring force of the spring, that is, in the direction of the thrust load generated when the card is forcibly pushed, and pushes the tip surface. Because it is constantly pressed against the receiving plate provided on the axis of the rotating shaft, during normal card feeding, the natural frictional force of the motor bearing and the spring elasticity against the inertial rotation of the motor after the power supply is stopped. Since the frictional force between the worm and the receiving plate, which is generated by the force (the remaining load obtained by subtracting the thrust load on the worm generated by the reaction force of the card feed roller minus the worm), acts as a brake, the card feed is maintained at a constant rate. Allows to stop at a position. When the card was forcibly pushed between the rollers during card feeding, the spring force was added to the thrust load generated when the card was forcibly pushed against the receiving plate against the worm. Because a strong brake is applied and the braking force can be increased more than during normal card feeding, the motor rotation after stopping the power supply is stopped at a fixed position, and the card feeding is performed regardless of the card pushing force. Can be stopped at a fixed position.

Note that there is a difference in the braking force between the normal card feeding and the case where the card is forcibly pushed in, as described above. Therefore, there is a strict difference in the card feeding stop position. In this case, it is possible to stop the card feed without a considerable error and to perform printing in a generally stable position.

As described above, the technical problems described above can be solved by the above means, and the problems of the conventional technology can be solved.

〔Example〕

Hereinafter, a preferred embodiment of the worm gear device for card feeding according to the present invention will be described in detail with reference to the accompanying drawings.

FIG. 1 is a side view showing an entire structure of a card feeding worm gear device according to the present invention, and FIG. 2 is a side sectional view showing the whole of the present invention in an exploded manner. A worm attached to the rotating shaft Ma of the motor M, and a feather key Mb is formed in the longitudinal direction (axial direction) of the circumferential surface of the rotating shaft Ma as shown in the enlarged sectional views of FIGS. A key groove 1b, which fits into the feather key Mb, is formed in the mounting hole 1a of the worm 1 into which the worm 1 is fitted, and the worm 1 rotates integrally with the rotation axis Ma. It is a mechanism that can slide freely in the direction. The feather key Mb may be formed on the worm 1 side, and the key groove Mb may be provided on the rotating shaft Ma side of the motor M. On the other hand, 2 is a rotating shaft for rollers, 3 is a worm wheel, 4
Is a card feed roller, and 5 is a pressing roller mounted on a shaft 6. These are the same members as those shown in the conventional apparatus described with reference to FIGS.

Next, 10 is a rotation axis Ma between the worm 1 and the motor M.
The numeral 10a denotes a key for preventing the worm push 10 from engaging with the stopper groove of the stopper R.

Numeral 11 is interposed between the worm push 10 and the motor M, and resiliently pushes the worm push 10 so that the worm 1 mounted on the rotary shaft Ma is moved to the tip side of the rotary shaft Ma, that is, the card T. Is pressed in the thrust load direction (left direction in the drawing) generated when the forcibly pushed in, and the tip surface of the worm 1 is constantly pressed against the receiving plate 13 provided on the axis of the rotating shaft Ma of the motor M as shown in FIG. Reference numeral 10b denotes a spring to be brought into contact with the front end pressing surface of the worm push 10, and 12 denotes a spacer interposed between the worm push 10 and the rear end surface of the worm 1.

The elastic force of the spring 11 is slightly larger than the thrust load (F _{1 in} FIG. 4) acting rightward in the drawing by the worm 1 when the card T is sent. Designed to press.

Since the worm gear device for card feeding according to the present invention has the configuration as described above, during normal card feeding, the frictional force generated in the bearing portion of the motor rotating shaft Ma with respect to the inertial rotation of the motor M after the power supply is stopped. And the frictional force generated on the worm 1 and the receiving plate 13 by the resilience of the spring 11 is applied as a braking force. Can be stopped.

When the card T is forcibly pushed between the rollers 4 and 5, the worm push 10 repelled by the spring 11 always presses the tip surface of the worm 1 against the receiving plate 13. In FIG. 1, the resilient force of the spring 11 is added to the thrust load in the left direction (the direction of the arrow Z in FIG. 5) to strongly act on the worm 1. Since the brake is applied more strongly and the rotation of the motor M after the power supply is stopped can be stopped at a fixed position, the card T can be stopped at a predetermined position.

〔effect〕

As described above, according to the card feeding worm gear device of the present invention, even if the card is forcibly pushed between the rollers, the elastic force of the spring is added to the thrust load generated by this forcible pushing, and the worm Because the brake is applied more powerfully than usual, it is possible to prevent the card from being pushed in
Since the rotation of the motor can be stopped in almost the same state as when the card is inserted with a normal force, the card feeding can be stopped at a predetermined position together with the stop of the power supply.

Therefore, when the present invention is used as a card feeding device of a printing machine, it can exhibit an advantage that printing can be performed at a generally determined printing step position regardless of the degree of insertion of a card insertion force, Combined with the fact that the configuration is simple and the implementation is easy, it is very suitable to be applied to various printing office equipment such as a time clock.

[Brief description of the drawings]

FIG. 1 is a side view showing the entire structure of the card feeding worm gear device according to the present invention in partial cross section, FIG. 2 is a side sectional view showing the entire structure exploded, and FIG. 3 is a worm with respect to a rotating shaft. FIG. 4 is a partial cross-sectional side view of a conventional example, and FIG. 5 is a partial cross-sectional side view of a conventional example showing a state when a card is pushed in. It is. 1 is a worm, M is a motor, Ma is a rotation axis, 2 is a roller rotation axis, 3 is a worm wheel, 4 is a card feed roller, 5 is a pressing roller, 10 is a worm push, 11 is a spring, 13 is a receiving plate, T is a card.

Claims (1)

(57) [Scope of request for utility model registration] A worm and a worm gear meshing with each other are mounted on respective rotating shafts of a motor and a card feed roller that intersect at right angles. When the motor rotates, the card feed roller is decelerated and rotated by the engagement of the worm and the worm gear. In a card feeder configured to feed a card inserted between a card feed roller and a pressing roller, the worm is mounted movably in an axial direction with respect to a rotation axis of a motor, and Between the worm and the worm, the worm is constantly pressed in the direction of the tip of the rotating shaft by receiving the spring force of the spring, so that the tip surface can be pressed against the receiving plate provided on the axis of the rotating shaft. A worm gear device for feeding a card, comprising a worm push configured as described above.