JPH0244357Y2 - - Google Patents

Description

[Detailed description of the invention] (a) Industrial application field The present invention relates to a head board for a tape recorder, which is configured to move a head board with a magnetic head mounted on the top surface forward from a stop position to a playback position using motor power. This relates to a control device.

(b) Prior art In recent years, playback operations on tape recorders have been performed with light touch operations, and the forward movement of the head board from the stop position to the playback position, which requires a large amount of mechanical operation force, has been achieved using a rotating body rotated by a motor. Those that use power are becoming popular.

That is, generally, the rotating body is provided with a cam portion, and the cam portion moves the head board forward from the stop position to the playback position.
In order to rotate the rotating body, a gear having a toothless portion is formed on the outer periphery of the rotating body, and the gear of this rotating body is meshed with, for example, a gear provided coaxially with the flywheel.

In conventional devices, the gears of the rotating body are engaged with the gears of the flywheel using a mechanical trigger accompanying the regeneration operation, for example, by the force of a separately prepared spring. There was a concern that external vibrations applied to the tape recorder could cause the gears to mesh inadvertently.

(c) Purpose of the invention The purpose of this invention is to solve the problems of the conventional method.When there is no need to move the head board forward, the engagement lever attracted to the permanent magnet is used to prevent the rotating body from moving inadvertently. When moving the head board forward, the solenoid generates a magnetic force that cancels the attraction force of the permanent magnet, releases the attraction of the engagement lever, and engages the rotating body with the electric mechanism and the rotating body. This was taken into consideration.

(d) Structure of the Invention In order to achieve the above object, the present invention provides a magnetic head, a head substrate which is always urged in one direction by a spring, and a head substrate which resists the force of the spring. a rotating body having a cam portion that moves the head board in the other direction; an electric mechanism that selectively engages with the rotating body to apply rotational power; and a locking protrusion provided on the rotating body. An engagement lever that selectively engages at one end, and a solenoid having a permanent magnet that attracts an iron piece provided at the other end of the engagement lever, and when no current is flowing through the solenoid, the permanent magnet Therefore, by attracting the iron piece of the engagement lever, the engagement lever cuts off rotational transmission between the rotary body and the electric mechanism, and by passing current through the solenoid during regeneration operation, a magnetic force is generated that cancels the attraction force of the permanent magnet. The iron piece of the engagement lever is released from the attraction of the permanent magnet, and the rotating body and the electric mechanism are brought into a state of rotation transmission.

(e) Embodiment An embodiment of the tape recorder of the present invention shown in the drawings will be described below.

In FIG. 1 viewed from the bottom of the chassis, a flywheel 3 connected to a motor 1 via a belt 2 has a gear portion 3a that meshes with a gear portion 4a on the outer peripheral surface of a rotating body 4 , and this meshing is established. At this time, the rotating body 4 rotates counterclockwise due to the rotational force of the motor 1. In the stopped state shown in FIG. 1, the gear portion 3a faces the toothless portion 4b on the outer peripheral surface of the rotary body 4 , and no meshing is established, so the rotary body 4 rotates with the shaft 5 on the chassis as the rotation axis. do not.

The rotating body 4 is provided with a protrusion 8 that engages with a spring wire 7 fixed to a fixing pin 6 provided on the chassis, and the spring pressure of the spring wire 7 causes the rotating body 4 to move counterclockwise. rotational force is given. The locking protrusion 9 of the rotating body 4 engages with an engagement pin 10a provided at the tip of the engagement lever 10. The engagement lever 10 is rotatable about a shaft 11, and an iron piece 10b is provided at the other end opposite to the one end where the engagement pin 10a is provided, and the iron piece 10b is connected to a solenoid. It is designed to be attracted to a permanent magnet in 12.

Further, the engagement lever 10 is biased counterclockwise by a spring 13.

The engaging surface of the above-mentioned locking convex portion 9 with the engaging pin 10a is formed so that the rotational force applied by the spring wire 7 of the rotating body 4 acts to rotate the engaging lever 10 in a clockwise direction. and the engagement lever 10
The clockwise rotational force applied to spring 1
3, the shape is set to be larger than the counterclockwise rotational force acting on the engagement lever 10.

However, normally, the attraction force due to the permanent magnet of the solenoid 12 is larger than the difference between the rotational force due to the spring pressure of the spring 13 against the engagement lever 10 and the rotational force due to the engagement between the locking protrusion 9 and the engagement pin 10a. Since the engagement lever 10 is biased counterclockwise, the engagement pin 10a on the engagement lever 10
The locking convex portion 9 engages with the rotating body 4 to prevent rotation of the rotating body 4, and the gear portion 4a of the rotating body 4 is prevented from meshing with the gear portion 3a of the flywheel 3.

When the play button is operated from such a stopped state,
When the solenoid 12 is energized by passing a pulse current, a magnetic force is generated in the solenoid 12 in the opposite direction to the attraction force between the permanent magnet and the iron piece 10b, and the attraction force of the permanent magnet is canceled out. As a result, the rotational force exerted on the engagement lever 10 due to the engagement between the engagement convex portion 9 of the rotating body 4 and the engagement pin 10a of the engagement lever 10 overcomes the rotational force exerted by the spring 13 and forces the engagement pin 10a out. The matching lever 10 rotates clockwise, and the rotating body 4 rotates counterclockwise. The gear portion 4a of the rotating body 4 meshes with the gear portion 3a of the flywheel 3, and the rotating body 4 is further rotated counterclockwise by the motor power applied through the gear portion 3a. (See FIGS. 2 and 3) Then, the engagement lever 10 goes through the state shown in FIG. 3, and then the iron piece 10b is attracted to the permanent magnet again as shown in FIG. 4b faces the gear portion 3a of the flywheel 3, and when the rotating body 4 stops rotating, the engagement pin 10a is engaged with the locking convex portion 9.

In FIG. 5 viewed from the top of the chassis, the head board 16 that interlocks the pinch roller 15 equipped with the magnetic head 14 is movable in the front-back direction within the dimensions regulated by the guide shafts 17, 17. It is always urged backward by the tensile force of the spring 18. A control pin 16a is installed on the lower surface of the head board 16, and the control pin 16a cooperates with a cam portion 19 provided on the rotating body 4 .

Therefore, as the rotating body 4 rotates counterclockwise as described above, the head base plate 16 resists the tensile force of the spring 18 due to the engagement relationship between the cam portion 19 and the control pin 16a, and moves to the fifth position. It moves forward from the stop position shown in the figure and reaches the playback position shown in FIG.

The present invention is provided with a locking lever 21 having a suction iron piece 21a that is suctioned by a solenoid 20 in order to hold the head board 16 that has moved forward in this manner in its forward position. The locking lever 2
1 is rotatably provided around a shaft 22, and is biased counterclockwise by a spring 23. The locking lever 21 is provided with a locking pin 21b, and the locking pin 21b is configured to cooperate with a dogleg-shaped side edge 16b formed on the head board 16.

The relationship between the locking pin 21b and the dogleg-shaped side edge 16b is such that when the head board 16 is at the stop position shown in FIG. 5, the lock lever 21 is rotated clockwise against the spring 23, and the lock A gap is inevitably created between the adsorption iron piece 21a of the lock lever 21 and the end face of the iron core of the solenoid 20, and the head board 16 moves forward as shown in FIG. 6 to the regeneration position. When the locking lever 21 reaches the position, the adsorption iron piece 21a of the locking lever 21 comes into close contact with the end face of the iron core of the solenoid 20.

In other words, this invention takes advantage of the property of an adsorption type solenoid: ``When the iron piece and the iron core of the solenoid are in close contact, the adsorption force is strong, but if there is even a slight gap between them, the adsorption force decreases rapidly.'' Therefore, there is no need to consider the timing of energization of the solenoid 20, and therefore, when the head board 16 moves forward from the stop position to the regeneration position, the solenoid 20
Even if the solenoid 20 is energized, the attraction force of the solenoid 20 does not act as a load on the movement of the head board 16, and when the head board 16 reaches the regeneration position, the locking lever 21 which is attracted to the iron core of the solenoid 20 The head board 16 can be held by the locking pin 21b.

(f) Effects of the invention Since the invention is constructed as described above, when the head board is moved forward from the stop position to the playback position using the rotational power of the motor, the engagement lever that is attracted to the permanent magnet is first moved. When moving the head board forward, all that is required is to generate a magnetic force in the solenoid to cancel the attraction force of the permanent magnet and release the attraction of the engagement lever. This makes it possible to operate the head board with a motor.

[Brief explanation of the drawing]

The figures show the device of the present invention;
5 and 4 are plan views in different states as seen from the bottom surface of the chassis, and FIGS. 5 and 6 are plan views in different states as seen from the top surface of the chassis. DESCRIPTION OF SYMBOLS 1... Motor, 3a... Gear part of flywheel, 4 ... Rotating body, 4a... Gear part, 4b... Missing tooth part, 7... Spring wire, 9... Locking convex part, 10... Engagement lever, 10a...Engagement pin,
10b... Iron piece, 12... Solenoid, 13... Spring.

Claims (1)

[Scope of utility model registration request] A rotating body having a head substrate provided with a magnetic head and always urged in one direction by a spring, and a cam portion that engages with the head substrate and moves the head substrate in the other direction against the force of the spring. , an electric mechanism that selectively engages with the rotating body to apply rotational power; and an engagement lever that has one end selectively engaged with a locking protrusion provided on the rotating body;
and a solenoid having a permanent magnet that attracts an iron piece provided at the other end of the engagement lever, and when no current is flowing through the solenoid, the permanent magnet attracts the iron piece of the engagement lever and causes the engagement lever to engage. The engagement lever cuts off the rotational transmission between the rotary body and the electric mechanism, and during regeneration operation, current is passed through the solenoid to generate a magnetic force that cancels out the attraction force of the permanent magnet, thereby removing the iron piece of the engagement lever from the attraction of the permanent magnet. 1. A head board control device for a tape recorder, characterized in that the rotating body and the electric mechanism are configured to bring the rotating body into a rotation transmission state.