JPH0110771Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a clutch mechanism suitable for use in a reel drive mechanism of a small-sized video tape recorder.

As a reel stand drive mechanism for a video tape recorder, one in which two reel stands are directly driven by a motor, and one in which the drive mechanism for the reel stands is displaced depending on the mode has been proposed, but in the case of the former The cost is high, and the latter has a complicated structure, which is an obstacle to miniaturization.

Therefore, in view of the above points, the present invention aims to realize a reel stand drive mechanism that can run the tape in both directions by simply changing the rotation direction of a single motor without displacing the drive mechanism. This paper proposes a clutch mechanism.

Hereinafter, a case in which the clutch mechanism of the present invention is applied to a reel stand drive mechanism will be described with reference to the drawings.

FIG. 1 is an exploded perspective view showing the lower part of the take-up reel stand 10. The lower part of the take-up reel stand 10 includes an annular felt 11 and a leaf spring 12 forming arcuate claws 12a, 12a. , an inclined protrusion 13a inside,
13a and a driven gear 13 having locking protrusions 13b, 13b are disposed, and these are pivotally supported by a shaft (not shown in FIG. 1) on the chassis. The feature of this embodiment lies in the clutch mechanism composed of a leaf spring 12 and a driven gear 13.

That is, the arcuate claw portion 12 of the leaf spring 12
a, 12a are formed to be inclined gradually downward in the counterclockwise direction, and the inclined protrusions 13a, 13a of the opposing driven gear 13 are inclined highly clockwise, and the inclined protrusions 13a, 13a are inclined counterclockwise. Locking protrusions 13b, 13b are formed on the direction side, that is, on the inclined lower end side of the inclined protrusions 13a, 13a.

Therefore, when the driven gear 13 rotates clockwise as schematically illustrated in FIG.
Since the tips of 2a and 12a are engaged with the locking protrusions 13b and 13b, the felt 11 attached to the leaf springs 12a and 12a does not come into pressure contact with the take-up reel stand 10, so that the rotational force of the driven gear 13 is reduced. It is not transmitted to the take-up reel stand 10, and the take-up reel stand 10 does not rotate in the direction of the arrow [see FIG. 2A].

On the other hand, when the driven gear 13 rotates counterclockwise, the arcuate pawls 12a, 12a are displaced upward along the inclinations of the inclined protrusions 13a, 13a, respectively, so that the felt 11 is moved onto the take-up reel. The driven gear 13 is pressed against the stand 10 and drives the take-up reel stand 10 [see FIG. 2B]. Therefore, in this embodiment, the driven gear 13 is
Only when rotating in the counterclockwise direction, the take-up reel stand 10 is felt-driven at a rotation speed of about 1/2 of the driven gear 13.

In this embodiment, a supply section is arranged opposite to the above-mentioned winding section. As shown in FIG.
A plate spring 22 and a driven gear 23 are arranged, and the claw part 22
a, 22a, the shapes of the inclined protrusions 23a, 23a, and the positions of the locking protrusions 23b, 23b are reversed from those of the winding portion described above. Therefore, this supply unit only moves in the supply reel stand 2 when driven clockwise.
0 clockwise at approximately 1/2 the speed of the driven gear 23.

Therefore, in this embodiment, as shown in FIG.
An intermediate gear 30 is meshed with both driven gears 13 and 23, and a drive gear 31 for fixing the motor shaft is also meshed with this intermediate gear 30.

Therefore, when the driving gear 31 rotates the intermediate gear 30 in the counterclockwise direction F as shown by the dotted line,
Both driven reel stands 10 and 20 rotate clockwise, the supply reel stand 10 is driven clockwise, and the tape is rewound to the supply side. In this case, what makes the tape running speed during recording and reproduction different from the tape running speed during fast forwarding is the drive voltage applied to the motor. On the other hand, when the intermediate gear 30 rotates in the clockwise direction R as shown by the solid line, the driven reel stands 10 and 20 both rotate counterclockwise, and the take-up reel stand 20 rotates counterclockwise. the tape is wound.

As mentioned above, by using the clutch mechanism of the present invention, it is possible not only to drive only the reel stand that should be driven by simply changing the rotation direction of the motor, but also to downsize the drive mechanism and reduce manufacturing costs. A possible reel stand drive mechanism can be obtained.

[Brief explanation of the drawing]

Each of the figures shows an embodiment of the present invention; FIG. 1 is an exploded perspective view of the winding section, FIGS. 2 A and B are explanatory views of the operation of the winding section, and FIG. 3 is an exploded perspective view of the supply section. , and FIG. 4 are illustrations for explaining the rotation direction of this embodiment. 10... Take-up reel stand, 20... Supply reel stand, 1
1, 21... Felt, 12, 22... Leaf spring, 12
a, 22a...claw portion, 13, 23...driven gear, 13
b, 23b...locking protrusion.

Claims (1)

[Claims for Utility Model Registration] It has an output rotating body and an arcuate claw portion that is gradually inclined downward in the circumferential direction, the upper surface of which can be pressed into contact with the lower surface of the output rotating body. A plate spring is provided, an inclined protrusion facing the arcuate claw part and inclined in the same direction as the inclination direction of the arcuate claw part, and a locking protrusion on the lower end side of the inclined protrusion. and an input rotating body disposed on the lower surface side of the leaf spring.