JPS647475Y2 - - Google Patents

Description

[Detailed Description of the Invention] [Industrial Field of Application] The present invention relates to a mode switching mechanism for a tape recorder that uses the driving force of a motor to switch between various operation modes through the operation of a single solenoid.

[Prior art]

There are three basic operations for a tape recorder: recording/playback, fast forward, and rewind. There is a tape recorder in which such switching between operating modes can be carried out by a so-called feather touch by utilizing the operating force of a solenoid.

In such tape recorders, there are special solenoids for each mode, such as a solenoid that moves the head board to the recording/playback position, and a solenoid that controls the tape drive system that moves the drive gear that transmits the rotation of the motor to the supply reel stand and take-up reel stand, respectively. Modes are switched by using a plurality of solenoids and controlling each solenoid according to each operating mode. Therefore, since a plurality of solenoids for mode switching are required, the size is bulky, which hinders miniaturization, and also has drawbacks such as high cost and high current consumption. In order to solve the above-mentioned drawbacks, the present applicant has proposed a tape recorder that can be set to each mode with a single solenoid, but the drive arm may malfunction when changing from the recording/playback mode to the stop mode.

[Purpose of invention]

In view of the above-mentioned drawbacks, the present invention enables mode switching by switching the operating time of one solenoid to long or short, thereby reducing weight, size, cost, and power consumption. The purpose of the present invention is to propose a mode switching mechanism for a tape recorder that prevents malfunction by holding the drive arm with a control arm so as to skip over the fast forward mode when switching from the recording/playback mode to the stop mode.

(Structure of the invention) The present invention includes a solenoid, a trigger arm and a control arm whose swing is controlled by the solenoid, and a control arm which is rotationally controlled by the trigger arm and operates in the following modes: stop → recording/playback or rewind → fast forward → stop. The driving gear is connected to the take-up reel by an assist gear having a first cam that performs cyclic operation, a slide plate slid by the solenoid, and a second cam formed on the assist gear, or by the slide plate. and a swingable drive arm that connects the drive gear to the supply reel, and a short-time operation of the solenoid changes the recording/playback mode to a fast-forward mode, and a long-time operation of the solenoid changes the recording/playback mode to a stop mode. At the time of switching, the control arm and the drive arm engage to restrict the connection between the drive gear and the take-up reel, skipping the fast-forward mode and transitioning to the stop mode, and switching from the stop mode to the solenoid for a long time. In operation, the drive arm is swung by the slide plate to connect the drive gear with the supply reel and switch the mode to a rewind mode.

〔Example〕

Hereinafter, the present invention will be explained with reference to an illustrated embodiment. Figure 1 shows the mode switching mechanism of a tape recorder.
FIG. 2 is a plan view seen through, and both are in the stopped position. A pair of tongue-shaped portions 1a and 1b, which are formed by punching out downward from the substrate 1, each have a reel shaft 1.
0 and 11 are fixedly planted, and a tape supply reel stand 12 and a tape take-up reel stand 13 are rotatably inserted into each of these reel shafts 10 and 11.
A gear 14 is integrally formed on the supply reel stand 12, a small diameter gear 15 is integrally formed on the take-up reel stand 13, and a large diameter gear 16 is attached thereon via a friction mechanism. gear 1
5 includes a gear 17 rotatably supported on the substrate 1.
are always engaged. A flywheel 2 integrally having a capstan shaft 18 is rotatably supported on the board 1, and the capstan shaft 18 penetrates through the board 1 and projects above the board 1. The flywheel 2 has a circumferential groove, and is rotatably driven by a drive motor 20 via a belt 19 placed around the circumferential groove. The flywheel 2 has a small diameter gear 2a
and a pulley 2b, and a reel stand driving belt 21 is hung on the pulley 2b.

A drive arm 3 is supported by a shaft 22 below the base plate 1 so as to be rotatable within a plane parallel to the base plate 1. A shaft 23 is fixedly attached to one arm of the drive arm 3 facing downward. A drive gear 24, friction felt, and pulley 25 are inserted into the shaft 23 and pressed from below by a coil spring, so that the rotational force of the pulley 25 is transmitted to the gear 24 by the friction between the gear 24 and the pulley 25. A cam portion 3a protruding obliquely is formed on the side of the other arm of the drive arm 3, and a bent raised portion 3b
is formed. The rising portion 3b is exposed on the substrate 1 through a window hole in the substrate 1 and protrudes toward a head substrate 4 described below. The drive arm 3 further has another arm 3c, the tip of which is formed with a downward bent portion 3d. The drive arm 3 further has another arm, the arm being formed with a bent portion 3e.

A bell crank-shaped play arm 5 is rotatably supported on the lower surface of the substrate 1 between the flywheel 2 and the take-up reel stand 13 in a plane parallel to the surface of the substrate 1. A small-diameter play gear 26 is rotatably supported above one end of the play arm 5. The play gear 26 is close to the side of the gear 16 of the take-up reel stand 13. The play gear 26 is located under the one arm end of the play arm 5.
A play pulley 27 is provided integrally with the shaft. A prismatic protrusion 5a is integrally formed on the upper surface side of the other arm end of the play arm 5. The protrusion 5a passes through an escape hole formed in the substrate 1, and is brought into contact with the regulating portion 4a of the head substrate 4.

When the play arm 5 is rotated clockwise in the figure, the play gear 26 can mesh with the gear 16 of the take-up reel stand 13;
As shown in the figure, when the projection 5a of the play arm 5 is in contact with the regulating portion 4a of the head board 4, the play gear 26 is separated from the gear 16. The belt 21 is hung on the pulley 25, and the belt 21 is connected to the pulley 25 and the flywheel 2.
A play pulley 27 is pressed from the outside between the pulley 2b and the pulley 2b.

Therefore, when the flywheel 2 is rotationally driven via the belt 19, the pulley 25 and the play pulley 27 are rotated via the pulley 2b and the belt 21.
is driven to rotate. Also, the play pulley 27 is pushed by the tension of the belt 21, and the play arm 5 is urged to rotate clockwise in the figure, but normally, as described above, the protrusion 5a is located at the restricting portion of the head board 4. 4a, rotation by the biasing force is restricted.

An assist gear 6 is attached to the shaft 28 on the bottom side of the board 1.
is rotatably supported. Assist gear 6
A gear 2a integral with the above-mentioned flywheel 2 is located adjacent to the side thereof. As shown in detail in FIG. 3, the assist gear 6 has toothless portions 6a and 6b. The upper surface side of the assist gear 6 is formed into a raised disk shape, and
An outer cam portion 6c and an inner cam portion 6d are formed on this disc-shaped raised portion. In the outer cam portion 6c, a portion of the outer periphery 6e of the disk-shaped raised portion is cut off so that the diameter thereof is gradually reduced. As shown in FIG. 1, a bent portion 3d of the drive arm 3 is located on the side of the outer cam portion 6c.
is located. The inner circumferential cam portion 6d has a linear shape with a smoothly continuous portion from the distal arc portion to the mesial arc portion, and a gentle valley-like portion 6f formed in the remaining portion and connecting the mesial arc portion and the distal arc portion. 6g portion
It has the following. On the underside of the assist gear 6, there are four protrusions 6 as regulating parts as shown in Fig. 3 and below.
h, 6i, 6j, and 6k are formed. Projection 6
h, 6j, and 6k are on the same circumference, and the protrusion 6i is closer to the inner circumference than the other protrusions. The assist gear 6 is configured to be rotated clockwise in the figure by the gear 2a, as will be described later.
The rear end portion of the protrusion 6i is formed obliquely from the outer diameter side toward the inner diameter side with respect to this rotation direction.

A solenoid 7 having a plunger 7a is attached to the lower side of the base plate 1 as shown in FIG. A circumferential groove 7b is formed near the tip of the plunger 7a. A pin 8a formed at the end of one arm of a bell crank-shaped trigger arm 8 is provided in the circumferential groove 7b.
is engaged. Near pin 8a is the same pin 8a.
A pin 8b longer than the pin 8b is integrally formed.
protrudes from the upper surface of the substrate 1. A pin 8c is integrally formed at the other end of the trigger arm 8. The trigger arm 8 is biased to rotate clockwise by a spring 29, but the pin 8b hits the edge 1c of the relief hole of the base plate 1 in FIG. 2, so that the rotation due to the biasing force is restricted. The trigger arm 8 is activated by the plunger 7a when the solenoid 7 is energized.
When the pin 8c is attracted, the pin 8c rotates counterclockwise in FIG.
Moves to the inner circumference side of 6j and 6k, and solenoid 7
When demagnetized, the pin 8c rotates clockwise in FIG. 1 due to the elasticity of the spring 29, and the pin 8c advances onto the passage of the protrusion 6h or 6j, 6k of the assist gear 6. The operating time of the solenoid 7 is selectively switched between long-time operation and short-time operation according to the operating mode.

A head substrate 4 is provided on the upper surface side of the substrate 1 so as to be slidable in the front-rear direction in FIG. 2 by appropriate guide means. A pinch roller shaft 30 is fixed to the right end of the head substrate 4 in FIG. Biased lever 3 by pinch roller shaft 30
1 is rotatably supported in a plane parallel to the head substrate 4, and a pinch roller 32 is rotatably supported. The biasing lever 31 has a pin 34 at its free end and is biased by a spring 33 to rotate counterclockwise in FIG. Assist gear 6 is located at the corner between part 6g.
By holding the head board 4 at a predetermined rotational position, the rotation due to the biasing force is restricted, and the head board 4 is retreated to a stop position on the front side. In this state, the toothless portion 6a of the assist gear 6 is held at a position slightly spaced apart from the gear 2a of the flywheel 2. A coil spring 35 is applied between the biasing lever 31 and the head board 4, so that when the biasing lever 31 is moved, the head board 4 is temporarily moved together with the biasing lever 31. . A recording/reproducing head 36 and an erasing head 37 are attached to the head substrate 4 by appropriate means.

The head substrate 4 is formed with a downwardly bent portion 4b directed toward the drive arm 3. Bending part 4
b extends downward through the substrate 1, and normally comes into contact with the cam portion 3a of the drive arm 3 to hold the drive gear provided on the drive arm 3 and each reel stand in a non-coupled position. A slide plate 9 is attached to the left side of the head board 4 in FIG. 2 so as to be slidable in the left-right direction by appropriate guide means.

The slide plate 9 is biased by a spring 38 to move to the right in the figure, and the protrusion 9a abuts the pin 8b of the trigger arm 8, thereby restricting movement by the biasing force. A step 9b is formed on the left side edge of the slide plate 9. When the slide plate 9 is moved toward the front in FIG. 2 along with the head board 4 while being moved to the left in FIG. 2 against the force, the stepped portion 9b
When the slide plate 9 and the head substrate 4 come into contact with the protrusion 1d formed on the substrate 1, movement of the slide plate 9 and the head substrate 4 is restricted midway. A protrusion 9c is formed at one end of the slide plate 9 and extends toward the rising portion 3b of the drive arm 3. The tip of the protrusion 9c is obliquely cut to form a slope 9d. Projection 9
Normally, the virtual extension line of c is on the right side of the rising part 3b of the drive arm 3 in FIG.
When the slide plate 9 is moved to the left in FIG. 1 through the pin 8b, the slope 9d of the protrusion 9c faces the rising portion 3b of the drive arm 3, and the slide plate 9 moves forward together with the head board 4 in FIG. Then, the rising portion 3b of the drive arm 3 is raised by the slope 9d.
is pushed to the right in the diagram.

In FIG. 1, a control arm 39 is rotatably supported by a support shaft 40 on the front side of the plunger 7a, and is biased clockwise by a spring 41. The control arm 39 is formed with a claw portion 39a that controls the bending portion 3e of the drive arm 3 and a piece 39b that contacts the pin 8a of the trigger arm 8. When the solenoid 7 is activated, the claw portion 39a and the bent portion 3e are engaged.

Next, the operation of the above embodiment will be explained.

Recording and reproducing operation When the solenoid 7 is activated with a short pulse of electricity when the drive motor 20 is started or at the same time as the activation, the plunger 7a is attracted by the operation of the solenoid 7, and the trigger arm 8 resists the force via the pin 8a. and rotate counterclockwise to release pin 8.
c pushes the rear end of the protrusion 6i of the assist gear 6 to rotate the assist gear 6 slightly clockwise. This causes assist gear 6 to shift to gear 2a.
The assist gear 6 is rotated clockwise by the gear 2a. The solenoid 7 is demagnetized while the pin 34 is in the large diameter arc of the cam portion 6d, the trigger arm 8 returns to its original position, the pin 8c returns to the path of the protrusion 6j of the assist gear 6, and the slide plate 9 is released from the spring. I will restore him to his old position at 38. At this time, the control arm 39 is temporarily moved to the drive arm 3.
It comes to a position where it blocks the bent portion 3e, but returns to a position where it does not block as the solenoid 7 is demagnetized.

As the assist gear 6 rotates, the cam portion 6d of the assist gear 6, which the pin 34 of the biasing lever 31 comes into contact with, shifts from a large-diameter arc portion to a small-diameter arc portion, and the pin 34 is moved forward in FIG. 4.
Since the biasing lever 31 having the pin 34 is temporarily integrated with the head board 4 via the spring 35, the biasing lever 31 and the head board 4 move together as the pin 34 moves. Since the trigger arm 8 and slide plate 9 have also returned to their original positions due to the demagnetization of the solenoid 7, when the slide plate 9 moves forward together with the head board 4, the downward bent portion 4b
The restriction on the cam portion 3a of the drive arm 3 is released, and the drive arm 3 can be rotated clockwise by the tension of the belt 21, and the rotation of the assist gear 6 causes the bent portion 3d of the drive arm 3 to move toward the assist gear 6. Clockwise rotation of the drive arm 3 is also restricted by slidingly contacting the outer periphery 6e of the same radius of the disc-shaped protrusion other than the cam part 6c forming part, and the drive arm 3 has its drive gear 24 connected to the gear 14. It is held in a position where it does not mesh with the gear 17 or the gear 17. Due to the movement of the head board 4, the projection 5a of the play arm 5 is disengaged from the regulating part 4a of the head board 4, and the play arm 5 is rotated clockwise by the urging force based on the tension of the belt 21, and the play gear 26 is moved from the gear 16. Engage with each other. The play gear 26 is already rotationally driven via the flywheel 2, the pulley 2b, the belt 21, and the play pulley 27, and the play gear 2
6 rotates the gear 16 and the take-up reel stand 13, and the tape is wound onto the take-up reel. At the same time, the pinch roller 32 supported by the pinch roller shaft 30 of the head board 4 presses the tape (not shown) against the capstan shaft 18 and transports the tape at a constant speed, and the magnetic heads 36 and 37 slide against the tape. Recording and playback starts.

The assist gear 6 rotates until its protrusion 6j is locked by the pin 8c of the trigger arm 8. The fourth protrusion 6j is locked by the pin 8c.
In the state shown in FIG. 5, the gear 2a is located at the toothless portion 6b of the assist gear 6, and the assist gear 6 is not rotated. Further, at this time, the pin 34 of the biasing lever 31 is located in the valley portion 6f of the cam portion 6d of the assist gear 6, and the biasing lever 31 is slightly retreated from the most advanced position. but,
The amount of advancement of the biasing lever 31 is somewhat greater than the amount of advancement of the head board 4, and the pinch roller 32 contacts the capstan shaft 18 with appropriate pressure. is absorbed by spring 35. In this recording and reproducing state, the pin 34 pushes the trough portion 6f and the straight portion 6g of the cam portion 6d of the assist gear 6 due to the return force of the biasing lever 31 based on the stored force of the spring 33 and the head board 4. 6 in the clockwise direction in FIG.

Fast Forward Operation To switch from recording/reproduction to fast forward, the solenoid 7 is operated for a short period of time to perform the fast forward operation in the recording/reproduction state. The activation of the solenoid 7 causes the trigger arm 8 to rotate counterclockwise, and the pin 8c moves from the passage of the protrusion 6j toward the center of the assist gear 6 and is disengaged. The assist gear 6 has a spring 33 that returns the head board 4.
The assist gear 6 rotates based on the biasing force, engages with the gear 2a, and disengages after a certain period of time, and the pin 34 pushes the trough portion 6f and the straight portion 6g of the cam portion 6d, thereby rotating clockwise. However, as shown in Figure 6, the trigger arm 8
The pin 8c locks the protrusion 6k and prevents the assist gear 6 from rotating. Assist gear 6 during this time
As the head board 4 rotates, the head board 4 moves backward to some extent, but the head board 4 is at an intermediate position with the pinch roller 32 separated from the capstan shaft 18 by some extent. Gear 2a does not yet mesh with assist gear 6. The bent portion 3d of the drive arm 3 faces the cam portion 6c of the assist gear 6, and the drive arm 3 is in a state where it can rotate clockwise.

At this point, the bent portion 4b of the head board 4 has escaped from the cam portion 3a of the drive arm 3 to the front in the figure, so the drive arm 3 rotates clockwise based on the tension of the belt 21, and the drive gear 24 gear 17
Engage with each other. The rotational force of the drive gear 24 driven via the belt 21 and pulley 25 is transmitted to the take-up reel stand 13 via the gear 17 and the gear 15, and the take-up reel stand 13 is driven to rotate at high speed to roll the tape. Fast forwarding is performed.

The queue mode can be set by reproducing the signal detected by the magnetic head 36 simultaneously with fast forwarding of the tape.

At this time, the control arm 39 temporarily comes to a position where it blocks the bending portion 3e of the drive arm 3, but the solenoid 7
Returns to the unblocked position by demagnetization.

If the fast-forward operation is to be performed immediately from the stop position, the control circuit is used to enter the fast-forward operation state after a short period of time has elapsed from the recording/reproducing mode.

Rewinding operation To enter the rewinding mode, the solenoid 7 is operated for a long time in the above-mentioned stop position. The long-term operation of the solenoid 7 causes the trigger arm 8 to rotate, and its pin 8c pushes the protrusion 6i of the assist gear 6, causing the assist gear 6 to rotate slightly and mesh with the gear 2a. As a result, the assist gear 6 is rotationally driven by the gear 2a as described above, and the head board 4 starts moving forward. Due to the continuous operation of the solenoid 7, the slide plate 9 remains moved to the left through the pin 8b, and the slope 9d of the protrusion 9c of the slide plate 9 moves to a position facing the rising portion 3b of the drive arm 3, and the head When the slide plate 9 moves together with the substrate 4, the slope 9d of the slide plate 9 pushes the rising portion 3b of the drive arm 3, causing the drive arm 3 to rotate counterclockwise and the drive gear 24 to mesh with the gear 14.
The tape is rotated at high speed on the supply reel stand 12 through the drive gear 24 and gear 14, and the tape is rewound onto the supply reel at high speed. While the head board 4 is moving forward,
The step portion 9b of the slide plate 9 hits the protrusion 1d, and the head substrate 4 is prevented from moving forward at an intermediate position before the recording/reproducing position, thereby preventing an unnatural situation in which the recording/reproducing position is reached before entering the rewind mode. The protrusion 6j of the assist gear 6 is the pin 8c of the trigger arm 8.
The gear 2a is locked by the assist gear 6 and stops rotating, and the gear 2a faces the toothless portion 6b of the assist gear 6, so that the gear 2a does not mesh with the assist gear 6.

Incidentally, by reproducing the signal detected by the head 36 in the rewind mode, the review mode can be set.

Stopping Operation To switch from the recording/playback mode, fast forward mode or rewind mode to the stop mode, the solenoid 7 may be operated for a continuous long period of time. In recording playback or rewinding mode, pin 3 of biasing lever 31
4 is a valley-shaped portion 6 of the cam portion 6d of the assist gear 6
f, and the pin 34 of the biasing lever 31 is biased in the backward direction by the biasing force of the spring 33, so this biasing force biases the assist gear 6 in the clockwise direction. There is. Therefore,
In this state, the pin 8c of the trigger arm 8 is moved to the protrusion 6 of the assist gear 6 by the operation of the solenoid 7.
j, when the assist gear 6 escapes from the protrusion 6k in fast forwarding, the assist gear 6 rotates clockwise, and the assist gear 6, the head board 4, and each component are brought to the stop position as shown in FIGS. 1 and 2. The recording/playback and fast-forwarding or rewinding operations stop.

At this time, especially when returning from the recording/playback mode shown in FIG. 5 to the stop position shown in FIG. Bending part 4
Since the drive gear 24 provided on the drive arm 3 cannot be held in a position where it is not connected to the respective reel stands, the drive arm 3 has a protrusion 9c on the right side of the rising part 3b, so the clock Although it is possible that the driving gear 24 and the gear 17 may be engaged with each other by rotating under the tension of the belt 21 in the direction shown in FIG. Therefore, meshing between the drive gear 24 and the gear 17 is prevented.
When the head board returns further, the cam portion 3 of the drive arm 3
The movement of the drive arm 3 is caused by the downward bending portion 4b.
will be blocked. The operation of solenoid 7 is maintained until this point.

[Effect of idea]

Since the present invention is constructed as described above, by selectively switching the operation time of one solenoid between long-time operation and short-time operation, the position of the head board can be changed to a stop position, a recording/reproducing position, or an intermediate position between these positions. In addition, since the slide plate is slid by a solenoid and controls the drive arm, it is possible to switch between three operating modes, including recording/playback mode, fast forward mode, and rewind mode, with the actuation force of a single solenoid. It is possible to do so,
Compared to conventional tape recorders that switch modes using actuation force, it is lighter, more compact, and less expensive. It also saves power and can be used with dry batteries. Built-in, when switching from recording/playback mode to stop mode due to long-term operation of the solenoid,
To provide a mode switching mechanism for a tape recorder, in which a control arm engages with a drive arm, so that the drive gear does not engage with the gear on the fast forward side when stopped from a recording/reproduction mode, and the tape is not unnecessarily fed, resulting in excellent practical effects. I can do it.

[Brief explanation of drawings]

The drawings show one embodiment of the present invention; FIG. 1 is a plan view of the tape recorder in the stopped state, looking through the board, FIG. 2 is a plan view of the tape recorder in the stopped state, and FIG. FIG. 4 is a plan view of the assist gear when it is stopped, FIG. 4 is a plan view of the assist gear during recording and reproduction, FIG. FIG. 6 is an explanatory diagram of operation in a fast forward state. 3... Drive arm, 4... Head board, 6...
Assist gear, 7... Solenoid, 8... Trigger arm, 9... Slide plate, 12... Supply reel, 13... Take-up reel, 24... Drive gear, 39... Control arm.

Claims (1)

[Scope of utility model registration request] It has a solenoid, a trigger arm and a control arm whose swing is controlled by the solenoid, and a first cam which is rotationally controlled by the trigger arm and which cyclically performs each mode of stop → recording/playback or rewind → fast forward → stop. An assist gear, a slide plate slid by the solenoid, and a second cam formed on the assist gear connect the drive gear to a take-up reel, or the slide plate connects the drive gear to a supply reel. Equipped with a swingable drive arm,
When the solenoid is activated for a short time to switch from the recording/playback mode to the fast forward mode, and when the solenoid is activated for a long time to switch from the recording/playback mode to the stop mode, the control arm and the drive arm are engaged and the drive gear is switched. and the take-up reel, and skips the fast-forward mode and shifts to the stop mode, and from the stop mode, the solenoid is operated for a long time to swing the drive arm by the slide plate, and the drive gear is moved to the stop mode. A mode switching mechanism for a tape recorder, characterized in that the mode switching mechanism is connected to a supply reel to switch the mode to a rewind mode.