JPH0756714B2 - Control device for arm rotation mechanism - Google Patents

Description

Description: TECHNICAL FIELD OF THE INVENTION The present invention relates to an arm rotation mechanism control device, and for example, control of an arm rotation mechanism used for torque transmission in audio equipment, video tape recorders, control equipment and the like. Regarding the device.

[Technical background of the invention]

Conventionally, many means have been used to rotate the arm in accordance with the rotation of the gear due to the frictional force between the gear provided on the swing arm and the arm. In particular, as in the case of reel driving of a tape recorder, it is often adopted in a mechanism portion that switches between reel driving on the supply side and the reel side.

[Problems of background technology]

However, in the conventional arm rotation mechanism, when the arm rotates and the gear provided on this arm meshes with the gear on the driven side, if the rotation speed of the gear on the driving side is high, the tooth tips of the gears are A collision occurs. For this reason, an accident may occur in which the gears do not mesh, and there is a problem in terms of reliability of power transmission.

In order to solve this problem, the frictional force between the drive-side gear and the arm may be increased or the rotational speed of the gear may be decreased. However, under the present circumstances, there is a strong tendency to reduce the size and weight of equipment, and a power transmission mechanism is required to rotate a small motor at high speed and to reduce the loss of driving force due to frictional force. Therefore, there is a problem that the solution by the above means conflicts with this requirement.

[Object of the Invention]

The present invention has been made in view of the above points, and it is an object of the present invention to provide a control device for an arm rotation mechanism that is capable of highly reliable power transmission using a small and lightweight device.

[Outline of Invention]

According to the present invention, a second gear that meshes with the first gear is rotatably supported on an arm that is rotatably supported coaxially with the first gear on the driving side, and the arm rotates. By using an arm rotating device configured to selectively engage the second gear with a plurality of third gears on the driven side,
By controlling the terminal voltage of the motor that drives the first gear when the arm rotates, to a range in which the second gear does not rotate, the intended purpose is achieved.

Example of Invention

An embodiment of a control device for an arm rotating mechanism according to the present invention will be described below with reference to the drawings.

FIG. 1 is an exploded perspective view showing the structure of an arm rotating device used in an embodiment of the present invention. A belt 4 is provided between the motor pulley 2 and the pulley 3 which are fixed to the rotating shaft of the DC motor 1. The pulley 3 is rotatably supported coaxially with the rotation fulcrum of the arm 5, and the first gear 6 is fixedly provided integrally with and coaxially with the pulley 3. A shaft 7 is planted on the arm 5, and a friction member 8 is attached to the shaft 7.
The second gear 9 is rotatably supported via. The second gear 9 is meshed with the first gear 6,
Further, the spring 10 urges it in the thrust direction, and the friction member 8 applies a frictional force in the rotational direction.
The second gear 9 is configured to be able to mesh with a plurality of, for example, two third gears 11 and 12 on the driven side by the rotation of the arm 5.

2 and 3 are plan views showing the operation of the arm rotating mechanism described above.

In FIG. 2, when the motor pulley 2 rotates in the arrow A ₁ direction, the pulley 3 rotates in the arrow B ₁ direction via the belt 4. The first gear 6 integrated with the pulley 3 also rotates in the direction of the arrow B ₁ and the second gear 6 meshes with the first gear 6.
Gear 9 rotates in the direction of arrow C ₁ . At this time, the arm 5 rotates in the arrow X direction by the frictional force of the friction member 8 urged by the spring 10 via the second gear 9. As a result, the second gear 9 meshes with the third gear 11, and the third gear 11 rotates in the direction of arrow D.

In FIG. 3, when the motor pulley 2 reverses and rotates in the direction of the arrow A ₂ , the first gear 6 and the second gear 6 are rotated as in the case of FIG.
The gear 9, arm 5, and third gear 12 are indicated by arrows.
Rotate in the directions of B ₂ , C ₂ , Y and E.

As described above, the second gear 8 selectively meshes with the third gear 11 or 12 by the rotation of the arm 5. At this time, as shown in FIG. 4, the applied voltage V to the motor 1 is set to v only during the time T ₁ required for the rotation of the arm 5, and the applied voltage v is set to the following expression. V ₂ ≦ v ≦ V ₃ Here V _2, V _3, as shown in FIG. 5, V ₂ is the arm 5 the voltage required to start a rotation, V ₃ a second which received the frictional force This is the voltage required for the gear 9 to start rotating. The fifth
In the figure, V ₀ is the starting voltage of the motor 1 when there is no load, V ₁ is the voltage required to rotate the pulley 3 via the belt 4,
B is a normal voltage when rotating the third gear 11 or 13.

As described above, while the arm 5 is rotating, the second gear 9 remains stationary and meshes with the third gear 11 or 12.
Therefore, unlike the conventional case shown in FIG. 7, the voltage B is applied to the motor 1 even when the arm 5 is rotating, and the second gear 9 does not rotate. As a result, the second gear 9 is the third gear.
When meshing with 11 or 12, these gears 9, 11, 12
A complete meshing is easily performed without being repelled by the collision of the tip circles.

FIG. 6 shows another embodiment of the present invention, in which the voltage applied to the motor 1 is continuously increased and the voltage is not changed while the arm 5 is rotating.
This is an example in which it is set between V ₂ and V ₃ , and it has the same effect as the above-mentioned embodiment.

In the embodiment described above, the rotation of the second gear is directly transmitted to the driven third gear, but the driven side is not limited to the gear, and for example, as well known. In some tape recorder reel stands, etc., a drum or roller having rubber on the outer periphery is configured to receive a rotational force. In that case, a rubber roller is coaxially arranged on the second gear. The rotation force may be transmitted to the driven rotating body by this roller. Even in the rotation transmission mechanism using a rubber roller, when the rotation arm rotates, the roller provided therein rotates,
When the driven roller is brought into contact with the driven roller, phenomena such as flipping may occur, and by applying the present invention, it is possible to suppress the occurrence of these phenomena and perform good operation.

〔The invention's effect〕

As described above, according to the present invention, since the second gear provided on the arm is controlled so as not to rotate during the arm rotation of the arm rotation mechanism, the rotation of the second gear is switched and transmitted to the driven side. When the gears rotate, problems such as collision of the tip circles of the gears and repulsion of the rollers do not occur, and highly reliable power transmission can be performed with a small and lightweight device.

[Brief description of drawings]

1 is an exploded perspective view showing the structure of an arm rotating mechanism used in an embodiment of the present invention, FIGS. 2 and 3 are plan views showing the operation of the arm rotating mechanism shown in FIG. 1, and FIG. 5 and 5 are graphs showing changes in motor applied voltage according to an embodiment of the present invention, FIG. 6 is a graph showing changes in motor applied voltage according to another embodiment of the present invention, and FIG. 7 is a conventional method. 6 is a graph showing a change in motor applied voltage due to 1 ... motor, 5 ... arm, 6 ... first gear 8 ... friction member, 9 ... second gear 11,12 ... third gear

Claims (1)

[Claims] 1. A first gear driven by a motor provided on a driving side, an arm rotatably supported coaxially with the first gear, and rotatably supported on the arm. A second gear that constantly meshes with the first gear; and a second gear that is provided between the second gear and the arm and that rotates the second gear together with the arm according to the rotation direction of the first gear. The friction member, a plurality of driven rotating bodies that are provided on the driven side and are selectively transmitted by the rotation of the second gear, and the supply voltage of the motor when the arm rotates. A control device for an arm rotation mechanism, comprising: a control means for setting a range in which the second gear does not rotate.