JPS6232365Y2 - - Google Patents

Description

[Detailed Description of the Invention] This invention relates to a transmission force switching mechanism for a tape recorder that switches the transmission force in a responsive manner.

A conventional transmission force switching mechanism will be explained with reference to FIG. In this figure, 1 is a chassis, 2 and 3 are a supply reel and a take-up reel rotatably supported on the chassis 1, 4 is a pin provided on the chassis 1, and 5 is a switching lever with a long length. Holes 6, 7, and 8 are provided, a pin 4 is inserted into the elongated hole 6, a spring 9 is stretched between the pin 4 and the hole 8, and a switching lever 5 is provided.
is urged in the direction of the pin 4 and rotates around the pin 4. 10 is a shaft provided on the switching lever 5 on the opposite side from the elongated hole 6; 11 is an idler rotatably supported on the shaft 10; 12 is a rubber attached around the idler 11; 13 is the The motor is supported by the chassis 1 and is capable of forward and reverse rotation, and its shaft 14 is inserted into a long hole 7 to which a pulley 15 is fixed. The pulley 15 and the rubber 12 are always in contact with each other.

Next, the operation will be explained.

When a voltage is applied so that the motor 13 rotates in the direction of the arrow A, the pulley 15 rotates in the direction of the arrow A, the idler 11 rotates in the direction of the arrow C, and the supply reel 2 rotates in the direction of the arrow I. As a result, the magnetic tape is rewound onto the supply reel 2 side.

On the other hand, when a voltage is applied so that the motor 13 rotates in the direction of arrow B, the pulley 15 rotates in the direction of arrow B and the idler 11 rotates in the direction of arrow D, and they are switched by the frictional resistance between the pulley 15 and the rubber 12. lever 5 begins to rotate in the direction of arrow H. As a result, the switching lever 5 rotates around the pin 4, and the idler 11 advances to the position shown by the two-dot chain line to rotate the take-up reel 3 in the direction of arrow J.
Therefore, the magnetic tape is wound onto the take-up reel 3 side.

Furthermore, when voltage is applied again to rotate the motor 13 in the direction of arrow A, the idler 11 rotates in the direction of arrow C as described above, and the switching lever 5 is rotated in the direction of arrow G about the pin 4. to rotate the supply reel 2 in the direction of arrow I.

In addition to the above, there is also an example in which the switching lever 5 is rotated via a lever using the driving force of an operation button to switch the rotational force of the motor 13 without using the frictional resistance between the rubber 12 and the pulley 15.

In the transmission force switching mechanism as described above, there is a time lag in switching, and the operating force of the operation button becomes large. Also, even if the power to motor 13 is turned off, motor 1
Since the rotational force transmission path No. 3 is secured, the magnetic tape runs due to the inertia of the motor 13 or the idler 11, which has the disadvantage of causing malfunction in detecting the position of the magnetic tape.

This idea was developed in view of the above points, and the displacement of the idler supported by the switching lever that transmits the rotational force of the motor is obtained by applying voltage to the piezoelectric element engaged with the switching lever. The present invention provides a transmission force switching mechanism for a tape recorder. This invention will be explained below based on the drawings.

Figures 2a and 2b are a plan view and a partially cutaway side view showing an embodiment of this invention.

In this figure, 21 is a chassis, 22 is a motor supported by the chassis 21 and capable of forward and reverse rotation.
23 is a shaft of the motor 22, 24 is a drive gear fixed to the shaft 23, 25 is a bearing rotatably inserted into the boss of the drive gear 24, and 26 is a switching lever press-fitted into the bearing 25. , 27 is a slot provided on the switching lever 26, 28 is an E ring attached to prevent the bearing 25 from coming off the boss of the drive gear 24, and 29 is a slot provided on the switching lever 26 on the opposite side from the slot 27. provided axis, 3
0 and 31 are intermediate gears inserted into the shaft 29,
A leaf spring 32 and a felt 33 functioning as a limiter are inserted between the intermediate gear 30 and the intermediate gear 31, and the intermediate gear 31 meshes with the drive gear 24. 34 are the intermediate gears 30, 31, and the leaf spring 3.
2. E-ring attaching the felt 33 to the shaft 29; 35 is a piezoelectric element (e.g. bimorph);
Lead wires 36 and 37 are connected to one end and supported by a support stand 38, and the other end is connected to a switching lever 26.
It is engaged with the slot 27. Note that the intermediate gears 30 and 31, the leaf spring 32, and the felt 33 function as idlers. Further, the lead wire of the motor 22 is omitted.

Next, the operation will be explained with reference to FIGS. 3 to 5. In these figures, 39 and 41 are a supply reel and a take-up reel, and gears 40 and 41 are arranged around each of them.
42 are provided.

When no voltage is applied to the motor 22 and the piezoelectric element 35, that is, in a stationary state in which the intermediate gear 30 and the gears 40, 42 are completely separated as shown in FIG.
When a voltage is applied to drive the intermediate gears 30 and 31 in the direction of arrow E, intermediate gears 30 and 31 rotate in the direction of arrow C. Furthermore, as the piezoelectric element 35 is distorted in the direction of arrow E, the switching lever 26 rotates in the direction of arrow G.
Then, since the intermediate gear 30 and the gear 40 mesh with each other, the supply reel 39 is moved by the arrow I by the motor 22.
direction, and the magnetic tape is rewound to the supply reel 39 side. This state is shown in FIG.

When the voltage that maintains the state shown in FIG. 4 is removed from the motor 22 and piezoelectric element 35, the motor 22 stops rotating and the distortion of the piezoelectric element 35 is removed, returning to the state shown in FIG. 3. Note that as soon as the voltage is removed, the distortion of the piezoelectric element 35 is removed, so the intermediate gear 30 immediately separates from the gear 40.

Further, when a voltage is applied so that the motor 22 is driven in the direction of arrow B and the piezoelectric element 35 is driven in the direction of arrow F in FIG. 3, the intermediate gears 31 and 30 are rotated in the direction of arrow D. Further, as the piezoelectric element 35 is distorted in the direction of arrow F, the switching lever 26 rotates in the direction of arrow H. Then, since the intermediate gear 30 and the gear 42 mesh with each other, the take-up reel 41 is rotated in the direction of arrow J by the motor 22, and the magnetic tape is wound onto the take-up reel 41 side. This state is shown in FIG.

When the voltage that maintains the state shown in FIG. 5 is removed from the motor 22 and piezoelectric element 35, the state shown in FIG. 3 is restored as described above.

As explained in FIGS. 3 to 5 above, the rotation direction of the motor 22 can be smoothly switched by changing the polarity of the voltage applied to the piezoelectric element 35, and the voltage can also be varied. Therefore, the pressing force, the pressing angle, the backlash, etc. between the intermediate gear 30 and the gear 40 or 42 can be set appropriately.

In the above embodiment, a motor 22 that rotates forward and backward is used, but a motor that rotates in one direction may be used and a gear switching mechanism may be used. In addition, intermediate gear 30 and gear 4
In order to quickly disengage the piezoelectric element 35 from the piezoelectric element 35 or the gear 42, a voltage opposite in polarity to the polarity that was used to press the two may be applied to the piezoelectric element 35 for a short period of time. Further, although the rotational force transmission path of the motor 22 is configured by meshing gears, a configuration other than gears, for example, a friction wheel may also be used.

As explained above, the transmission force switching mechanism of the tape recorder of this invention is configured to apply voltage to a piezoelectric element that engages a switching lever that supports an idler to switch the rotational force of the motor to the supply reel or the take-up reel. Therefore, the responsiveness of switching the transmission force becomes smooth and engagement and disengagement can be performed quickly. In addition, the configuration is simple and the idler cuts well, so
Malfunctions in magnetic tape position detection can be prevented. Furthermore, since the switching lever is displaced by a piezoelectric element, the operation button only needs to function to turn on and off the power, which has the advantage of making the operation button softer.

[Brief explanation of the drawing]

Figure 1 is a plan view of a conventional transmission force switching mechanism;
Figures a and b are a plan view and a partially cutaway side view showing an embodiment of this invention, and Figures 3 to 5 are explanatory diagrams of the operation. In the figure, 22 is a motor, 24 is a drive gear, 25 is a bearing, 26 is a switching lever, 27 is a slot, 3
0, 31 is an intermediate gear, 35 is a piezoelectric element, 36, 3
7 is a lead wire, 38 is a support stand, 39 is a supply reel, and 41 is a take-up reel.

Claims (1)

[Scope of utility model registration request] The rotational force of the motor is transmitted to the supply reel or the take-up reel via an idler supported by a switching lever, and by switching the direction of rotation of the switching lever, either the supply reel or the take-up reel is transferred. In a mechanism configured to drive one side, a piezoelectric element has one end fixed and the other end engaged with the switching lever, and a voltage application that displaces the piezoelectric element and switches the rotation direction of the switching lever. A transmission force switching mechanism for a tape recorder, characterized by comprising means.