JPS5823655B2 - Tape recorder drive mechanism - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a drive mechanism for a tape recorder, particularly a small cassette tape recorder such as a car stereo.

When the tape wound around a cassette is left unattended, the reel hub may rotate due to vibrations, causing the tape to become loose.

If the slack tape is loaded into a tape recorder and immediately fast-forwarded or rewound, the tape may become twisted or broken.

Therefore, before fast forwarding or rewinding, it is necessary to rotate the reel stand to remove slack in the tape.

Conventionally, this type of device rotates only one side of the reel stand, electrically detects when the slack in the tape is removed and the other reel stand begins to rotate, and when this rotation is detected, it enters the playback state. Therefore, it takes time to remove tape slack, and if a detection device that detects the rotation of the reel stand is also applied to a tape end detection device, it is necessary to install a special circuit to detect when the reel stand starts to rotate. Ta.

This invention was made in view of the problem of slanting, and its purpose is to provide a simple device that can quickly remove tape slack by rotating the reel stands relative to each other in the tape winding direction. To provide a drive mechanism for a tape recorder capable of detecting the end of the tape and quickly forwarding or rewinding the tape after removing tape slack.

Next, one embodiment of the structure will be described with reference to the drawings.

1 is a chassis, 2 is a motor attached to the chassis 1, 3 and 4 are first and second flywheels, and the lower ends of rotating shafts 3a and 4a are attached to a back plate 5 attached to the back of the chassis 1 The upper parts of the rotating shafts 3a and 4a are supported on resin bearing plates 6 and 7 attached to the chassis 1.

Note that the portions of the rotating shafts 3a, 4a that protrude upward from the bearing plates 6, 7 serve as capstans, and hence the rotating shafts 3a, 4a are hereinafter referred to as capstans.

Further, the bearing plates 6 and 7 have guide rods 6a, ?, which are fitted into guide holes of the cassette, respectively. a is integrally molded.

Reference numeral 8 denotes a pulley pivotally supported on a base plate for equipping a tape stop detection unit, which will be described later.
A belt 9 is wound around the boot IJ 2 b fitted on the rotating shaft 2 a of the belt 9 (see FIG. 2).

Therefore, when the motor 2 rotates, the first and second flywheels 3 and 4 and the pulley 8 are rotated.

Gears 3b and 4b are formed in the first and second flywheels 3 and 4, respectively.
b and the connecting gear 10a provided on the control levers 1o and ii.
, 11a, and the connecting gears 10a, 11a are meshed with each other.
a and the gears 12a, 13 of the first and second reel stands 12.13
a are meshed with each other.

Therefore, when the first and second flywheels rotate 3°4,
The first and second reel stands 12 and 13 each rotate in the direction of winding the tape.

The control levers 10 and 11 are approximately U-shaped, with one end 10b
.

11b is implanted in chassis 1 pin 1 a t 1
The other end control portions 10c and 11c, which are pivotally supported by b and are tensioned with a spring 11e, form a head 41 of a selection arm 41, which will be described later.
It corresponds to a.

The connecting gear 10a is located near the control units 10c and 11c.

11a is pivotally supported.

Therefore, when the control levers 10 and 11 are rotated about the pins Ia and lb, the connecting gears 10a and 11a are connected to the first and second reel stands.

The gears 12a and 13a of 12.13 move along the outer periphery of the gears 12a and 13a of
b, meshes with and separates from 4b.

Note that 10d and 11d are used when release levers 18 and 19, which will be described later, are rotated about pins Ia and 1b as fulcrums.

The control levers 10, 11 are engaged with each other, thereby moving the connecting gears 10a, 11a and the gear 3b.

This is an engagement piece for releasing the engagement with 4b.

14.15 is a release plunger attached to the back of the chassis 1, and a pin 14a is implanted in its suction rod;
15a protrudes from the top surface of the chassis 1 through a long hole.

Reference numerals 16 and 17 designate operating levers with the pins 14a and 15a pivotally supported at one end, and springs 18 and 1 between them and the chassis 1.
9 is installed.

Reference numerals 20 and 21 are release levers whose one end is pivotally supported by the operating lever 16 and the other end, and whose approximate center is the chassis 1 mentioned above.
It is pivotally supported by pins 1a and 'ib.

Reference numeral 22 designates a lock plate that is pivotally supported by a pin 1c implanted in the chassis 1, and has an upright piece 22a formed corresponding to the other end abutting piece of the release levers 20, 21, and a head stand 24, which will be described later. A lock piece 22b is formed to be engaged with a roller 24c attached to the roller 24c.

Note that this lock plate 22 is always given a clockwise rotational force by a spring 23.

Reference numeral 24 has a guide groove 24a in which a pin 1d embedded in the chassis 1 is guided, and a pin 24b guided in the guide groove bored in the chassis 1. This makes the head stand move in parallel. A reproducing head 25 is attached.

Note that in the case of a tape recorder having a recording function, the playback head 25 is used as a recording head, or a recording head is separately provided and an erasing head is attached to the head stand 24.

Further, a roller 24c is provided at the tip of the head stand 24, and when the head stand 24 moves forward, the lock plate 24c
The second lock piece 22b is engaged with the second lock piece 22b.

26.27 is a pinch roller unit, and the support frame 26
a, 27a are implanted into the chassis 1 pin 1 e, 1
This support frame 26a is pivotally supported by f.

Pinch rollers 26b and 27b are rotatably attached to 27a, respectively, and rollers 26c and 27 extend downward.
c is attached, and the above-mentioned pin 1e.

Winding springs 26d and 27d are provided which are wound around 1f and whose ends are engaged with support frames 26a and 27a.

Note that one end of these coiled springs 26d and 27d is attached to the head stand 2.
24d of upright pieces formed at both ends of 4.

It corresponds to 24e.

Also, the roller 26c. 27c is a notch 24f formed in the head stand 24.

I'm facing 24g.

Reference numeral 26 denotes a selection plunger attached to the chassis 1, which serves to select the forward movement of the head stand and the running direction of the tape.

Reference numeral 29 is a lever for advancing the head stand which is pivotally supported by a pin 1g planted on the back surface of the chassis 1, and is formed in a substantially dogleg shape, and one end of which has a fork 29b that is connected to the pin 24b of the head stand 24. A pin 29a is implanted at the other end.

Reference numeral 30 designates a control plate having an engaging pawl 30a pivotally supported by the pin 29a, and a clockwise rotational force is constantly applied by a coil spring 31 provided on the pin 29a to the lever 29 for advancing the head base. Formed upright piece 29c
is in contact with.

A spring 32 is stretched between the other end of the forward lever 29 and the chassis 1, and applies a counterclockwise rotational force to the lever 29.

When the head stand 24 is retracted and the forward lever 29 is rotated counterclockwise, the control plate 30 has an engaging pawl 30a engaged with a pin 28a implanted in the selection plunger 28. Furthermore, when the head stand 24 is moving forward, it is retracted to a position away from the movement trajectory of the pin 28a.

33 is a rotary lever supported by a pin 1h implanted in the chassis 1, and one end is a selection plunger! It is pivotally supported by 28 pins 28a.

A rotating arm 34 is pivotally supported by a pin 11 implanted in the chassis 1, has a pin 34a implanted at one end, and extends to the back surface of the chassis 1.

Note that when the head stand 24 is retracted, the rotating arm 34 is moved by the upright pieces 24d and 24 provided on the spatula 1 stand 24.
It comes into contact with f and is in a horizontal state.

Reference numeral 35 designates a swinging lever in which a pin 34a of the swinging arm 34 is passed through an elongated hole 35a, and a pin 35b implanted at one end is pivotally supported by the other end of the swinging lever 33.

Further, the other end of this swing lever 35 has two engaging claws 35c.
, 35d are formed.

Reference numeral 36 designates a control arm that is pivotally supported by a pin 1j implanted in the chassis 1, one end of a spring wire 37 is wound around the implanted pin 36a, and the approximately middle portion passes through a hole in the upright piece 236b. The distal end thereof is inserted between two protrusions 34b formed on the rotating arm 34.

Further, the control arm 36 is implanted with engaging rods 36 c t 36 d extending to the back surface of the chassis 1, and when the head stand 24 is moving forward, the engaging claws 35 c and 35 d of the swing lever 35 are engaged. engaged alternately.

38 is a torsion spring for selectively fixing the rotation of the control arm 360 in two positions.

A spring 39 is stretched between the swing lever 34 and the chassis 1 and pulls the lever 34 to the left.

40 is a slide lever in which a pin (not shown) implanted on the back surface of the yarn 1 is inserted into an elongated hole 40a and moves in parallel, and a groove 40b at one end of the slide lever is provided with an engagement provided in the control arm 36. The rod 36d is engaged.

This slide lever 40 has the above-mentioned pinch row.

The step portions 40c and 40d contact the rollers 26c and 27c of the RA units 26 and 27 to control the contact and separation with the capstans 3a and 4a, and the selection arm 410 which will be described later comes into contact with the rollers 41b and 4ic for selection. A stepped portion 40e that controls rotation of the arm 410.

40f is formed.

Reference numeral 41 denotes a substantially cross-shaped selection arm whose substantially center is pivotally supported by the pin 24b of the head stand 24 described above, and the head 41a of which is opposed to the control lever 10.11 described above.
Rollers 41' b t 41 c are provided at both ends located between 0c and 11c and extending in the lateral direction.

Reference numeral 42 designates a tape stop detection unit mounting plate, and on its lower surface are the above-mentioned pulley 8, a large gear 43 that meshes with the gear 8a formed on the pulley 8, and a small gear 43 formed integrally with the dog gear 43. A cam plate 44 having a gear 44a that meshes with the gear 43a provided on its outer periphery is pivotally supported.

A cam groove 44b is formed on the upper surface of this cam plate 44, which is the surface facing the mounting plate 42, and a cam base 44c is formed in the center.
is formed.

Also, on the bottom surface of the mounting plate 42 is the selection plunger 2 described above.
A switch 45 for energizing the switch 8 is attached, and a switch control lever 46 for controlling opening/closing of the switch 45 is pivotally supported.

One end of the lever 46 faces the switch 45, and the other end is pivotally supported by the end of the pin support lever 470.

An engaging pin 47a facing the cam groove 44b of the cam plate 44 is formed at the other end of the pin support lever 47, and its upper end passes through the guide groove 42a of the mounting plate 42.

48 is a guide rod 48a that is slidable in the guide groove 42a.
A guide pin 48b is pivotally supported in a small hole 42b of the mounting plate 42.

Further, a forked engagement piece 48c is formed on the detection arm 48, and an engagement pin 47a of the support lever 47 is engaged with this engagement piece 48c.

Reference numeral 49 is a detection lever having a hole 49a drilled in the center and pivotally supported by a pin 48d formed on the upper surface of the guide rod 48a of the detection arm 48, and elongated holes 49b at both ends thereof.

49c is worn.

And this long hole 49b. 49c includes the above-mentioned first and second
Reel stand 12゜130 Slip plate 12 provided on the bottom surface
b.

The protrusion 13b is engaged.

These slip plates 12b and 13b are the reel stands 12 and 1.
3 (the same applies to the first reel stand 12 side, so only the second reel stand 13 side will be explained with reference to FIG. 7), and the plate part 13f is fitted to the shaft part 13c of the third reel unit 13 (the same applies to the first reel stand 12 side, so only the second reel stand 13 side will be explained with reference to FIG. 7), and the plate part 13f is Pressed to the side.

Therefore, when no load is applied to the slip plate 13b, the slip plate 13b also rotates together with the reel stand 13, but when a load is applied to the slip plate 13b, it slips and stops rotating.

Note that the slip plate 12b. The protrusions 13b face the holes 42c and 42d of the mounting plate 42.

Reference numeral 50 is a track changeover switch whose contacts are switched in accordance with the rotation of the control arm 360 to switch the reproducing coil of the head 25, and 51 is a track changeover switch whose contacts are switched by the lever 29 for advancing the head stand when the head stand 24 advances. This is a switch that causes constant speed rotation, and vice versa when switched to high speed rotation.

The structure has been described above, and the operation will now be described.

When the cassette is not loaded, the head stand 24 is retracted, so the selection arm 41 is also retracted, and the control levers 10, 110 control section 10c.

11c is not displaced by the head 41a.

Therefore, the connecting gear 10a is the gear 3 of the first flywheel 3.
a and the gear 12a of the first reel stand 12, and the connecting gear 11a connects the gear 4a of the second flywheel 4 and the second
It is connected to the gear 13a of the reel stand 13a.

When a cassette (not shown) is loaded in this state, the motor 2 is energized by a power switch (not shown).

At this point, since the head stand 24 is retracted, the motor 2 is rotated at high speed in the direction of the arrow in FIG. 2 by the contact of the switch 51.

Therefore, both the first and second reel stands 12 and 13 are chi.

The tape is rotated in the winding direction, and if there is slack in the tape, this slack is removed.

Also, when the reel stand 12° 13 is rotated, the slip plate 12
b and 13b are also rotated in the same direction, so the detection lever 49
moves upward as shown in FIG.

When the guide rod 48a of the detection arm 48 moves within the guide groove 2a as the detection lever 49° moves, the detection arm 48 is rotated about the guide pin 48b, so that the engagement piece 48c is rotated to the right. displacement in the direction.

Since the engaging pin 47a of the support lever 47 is engaged with the displaced engaging piece 48c, the cam groove 4 of the cam plate 44
The lower end of the engagement pin 47a facing 4b is pressed against the inner circumferential wall of the cam groove 44b.

Therefore, even if the cam plate 44 is rotated by the pulley 8, the engagement pin 47a does not come into contact with the engagement portion 44d of the cam base 44c, and the engagement pin 47a maintains a state along the inner circumferential wall.

When the tape slack is removed, the rotation of the reel shafts 12c and 13c of the reel stand 12° 130 is stopped by the friction between the reel stands 12 and 13, so the slip plate 12b,
The rotational force of 13b disappears.

Note that the reel stands 12 and 13 are reel shaft portions 1-2c. 1
Since it is in a slip state at 3c, it continues to rotate.

On the other hand, since the cam plate 44 is constantly rotated by the pulley 8, the engagement pin 47a is moved toward the center by the inner circumferential wall of the cam groove 44b and maintained in that state.

Since the engaging portion 44d of the cam base 44c is located on the trajectory of the unmoved engaging pin 47a, the engaging pin 47a
a is pushed by the engaging portion 44d.

Therefore, the switch control lever 46 is rotated and the switch 4
Close 5.

Since this switch 45 is connected to the selection plunger 28, the plunger 28 is energized.

When the plunger 28 is energized and the suction rod is pulled, the pin 28a is engaged with the engaging pawl 30a of the control plate 30, so the control plate 30 is pulled and the head base advancement lever 29 is moved clockwise. is rotated.

Since the guide pin 24b of the head stand 24 is engaged with the bifurcated portion 29b of this lever 29, the head stand 24 moves forward, and the roller 24c provided at the tip engages with the lock piece 22b of the lock plate 22. be done.

Therefore, even after the selection plunger 28 is de-energized and the suction rod returns, the head stand 24 is fixed at the forward position.

Note that when the head base advancement lever 29 is rotated, the control plate 30 is rotated toward the upright piece 29c by the coiled spring 31, so the engaging claw 30a leaves the trajectory of the pin 28a of the plunger 28.

Therefore, when the head stand 24 is moving forward, the plunger 2
Even if the pin 28a is energized again, the pin 28a and the engaging claw 30a will not be engaged with each other.

On the other hand, when the head stand 24 moves forward, the pinch roller unit 2
When the rollers 26c, 27c of 6, 27 are disengaged from the notches 24f, 24g of the head stand 24, the coiled spring 26d is released from the middle of its forward movement.

Each pinch roller unit 26.27d is pushed by the upright pieces 24d, 24e.
27 is rotated by spring force toward the capstans 3a and 4a.

Here, if the slide lever 40 is moving to the right as shown in FIGS. 5 and 10, the pinch roller unit 260
Since the roller 26c contacts the stepped portion 40c of the slide lever 40 and the roller 41b of the selection arm 41 contacts the stepped portion 40e, rotation of the pinch roller unit 260 is stopped midway, and the pinch roller 26b contacts the capstan 3a. Never.

Further, the selection arm 41 is rotated counterclockwise to
a contacts the control portion 10c of the control lever 100 and moves it, so that the connection gear 10a and the gear 3 of the first flywheel 3
Remove the mesh with b.

On the other hand, since the roller 27c on the side of the pinch roller unit 27 is located away from the stepped portion 40d of the slide lever 40, rotation of the pinch roller unit 270 is not prevented, and therefore the pinch roller 27b is pressed against the capstan 4a.

Further, since the head 41a of the selection arm 41 and the control portion 11c of the control lever 110 do not come into contact with each other, the gear 4b of the second flywheel 4 and the second reel stand 13 are connected to each other by the connecting gear 11a.
continues to be connected to gear 13a.

Further, since the head stand advancement lever 29 switches the switch 51, the motor 2 rotates at a constant speed.

As a result, the head 25 comes into contact with the tape, the second reel stand 13 begins to rotate in the direction of winding the tape, and the tape is pinched between the capstan 4a and the pinch roller 27b, thus starting reproduction.

Next, a case will be described in which the playback progresses and the tape reaches its end.

If the tape is now wound on the second reel stand 13 side,
The slip plate 13b of the second reel stand 13 applies a clockwise turning force to the detection lever 49, and the slip plate 12b of the first reel stand 12 also applies a clockwise turning force.

Therefore, the detection arm 48 is rotated clockwise, and the engagement pin 47a of the pin support lever 47 is moved into the cam groove 44b of the cam plate 44.
It maintains a state along the inner circumferential wall of the cam base 44c and is not engaged with the engaging portion 44d of the cam base 44c.

Now the running of the tape has stopped and the first and second reel stands 12
, 130 reel shafts 12c, 13c are stopped, the switch 45 is closed and the selection switch is closed in the same manner as when the reel stands 12, 130 reel shafts 12c, 13c are stopped after removing the tape slack described above. The plunger 28 is energized.

When the plunger 28 is energized and the suction rod is pulled, the rotating lever 33 is rotated clockwise.

Note that since the head stand 24 of the control plate 30 is moving forward, the engaging claw 30a is retracted from the locus of the pin 28a, so the head stand advancement lever 29 is not rotated.

Here, the slide lever 40 is moving to the right, and the control arm 36 with the engaging rod 36d engaged with the groove 40b of the slide lever 40 is rotated counterclockwise. The movable arm 34 is rotated clockwise.

The swing lever 35, in which the pin 34a of the swing arm 34 is inserted into the elongated hole 35a, is rotated clockwise, and the engagement claw 35d is engaged with the engagement rod 36d of the control arm 36.

Therefore, when the rotation lever 33 is rotated clockwise and the swing lever 35 is pulled, the control arm 36 is rotated clockwise.

As a result, the slide lever 40 moves to the left as shown in FIG. 11, the roller 27d of the pinch roller unit 27 rides on the stepped portion 40d, and the roller 41c of the selection arm 41 rides on the stepped portion 40f.

Therefore, the pinch roller 27b is separated from the capstan 4a, and the control portion 11c of the control lever 11 is moved away from the selection arm 41.
is rotated clockwise and pushed by the head 41a, the connecting gear 11a is separated from the gear 4b of the second flywheel 4, and the rotational force to the second reel stand 13 is eliminated.

On the other hand, the roller 26d of the pinch roller unit 26
0c, the pinch roller 26b is pressed against the capstan 3a, and since the head 41a of the selection arm 41 is separated from the control part 10c of the control lever 10, the connecting gear 10a is connected to the gear 3b of the first flywheel 3 and the gear 3b of the first flywheel 3. It is connected to the gear 12a of the limp base 12.

This causes the tape to start running in the opposite direction, and the rotation of the control arm 360 switches the contacts of the switch 50 to switch the head 250 channel, so that tracks in the opposite direction are reproduced.

By the way, in the above state, the control arm 36 is rotated clockwise and the rotation arm 34 is rotated counterclockwise by the spring wire 37, so the swing lever 35 is rotated counterclockwise. Thus, the engaging claw 35c is held in a state where it can be engaged with the engaging rod 36c of the control arm 36.

Therefore, when the playback is finished again and the stop of tape running is detected by the same operation as described above and the selection plunger 28 is energized, the swing lever 35 rotates the control arm 36 counterclockwise and moves the slide lever 40. Pull it to the right, so
The above-mentioned initial state is reached and playback in the original direction is started.

If you want to change the playback channel during playback, close the switch using a replay button (not shown), energize the selection plunger 28, and switch the playback channel in the opposite direction in the same way as the above-mentioned operation after detecting the end of the tape. Playback becomes possible.

Next, a case will be described in which rewinding is performed during playback shown in FIG. 10, that is, during playback when the tape is being wound rightward.

When you press the rewind button (not shown) and close the switch,
The release plunger 15 is energized and its suction rod is pulled.

As a result, the operating lever 17 is pulled against the spring force of the spring 19, and the release lever 21 is rotated counterclockwise.
The tip of the spring 2
It rotates counterclockwise against the spring force of 3.

Therefore, the lock piece 22b and the roller 24c of the head stand 24 are unlocked, and the head stand moves backward by the force of the spring 32 via the lever 29 for advancing the head stand.

Further, since the release lever 21 is rotated counterclockwise, the engagement piece 11d of the control lever 11 is engaged with the release lever 21 and rotated, and the connecting gear Ila is separated from the gear 4b of the second flywheel 4, and the engagement piece 11d of the control lever 11 is engaged with and rotated. The 2-reel stand 13 becomes free.

On the other hand, the control portion 10c of the control lever 100 is no longer restricted by the head 41a of the selection arm 41 that retreats as the head stand 24 retreats, so it returns to its original position by the spring force of the spring 11e. The gear 3b of the first flywheel 3 and the drawer 12a of the first reel stand 12 are connected.

Further, the head stand 24 is moved backward, the head stand advance lever 29 switches the switch 51, and the motor 2 rotates at high speed.

Therefore, the first reel stand 12 rotates at high speed and winds up the tape.

When the rewinding of the tape is completed and the end of the tape is reached, the switch 45 is closed by an operation similar to the operation after detecting the end of the tape described above, and the selection plunger 28 is energized, and the release plunger 15 is de-energized. Then, the head stand 24 advances again to perform reproduction, but at this time, reproduction is performed in the direction that was being performed before rewinding.

This allows the rotating arm 34 to move when the head stand 24 is retracted.
The upright pieces 24d and 24f keep the swing lever 35 in a horizontal state, and the engaging claws 35 c t 35 d
This is because the control arm 36 is prevented from engaging with either of the engaging rods 36c, 36d.

Further, when returning to playback during rewinding, the power to the release plunger 15 is cut off by operating a replay button (not shown) or the like.

As a result, the operating lever 17 is returned by the spring 19 and the release lever 21 is returned, so that the control lever 11
returns to its original position.

Therefore, the connecting gear 11a is the gear 4 of the second flywheel 4.
b and the gear 13a of the second reel stand 13 are connected, so
The second reel stand 13 rotates in the opposite direction to the first reel stand 12, and if there is slack in the tape, the slack is removed.

When the slack is removed, the head stand 24 moves forward by the same operation as when loading the tape, and reproduction in the reproduction direction before rewinding is performed.

Next, a case will be described in which fast forwarding is performed during playback, that is, during playback when the tape is being wound in the right direction.

When you press the fast forward button (not shown) and close the switch,
After the release plunger 14 is energized and the entire tape is wound in the same way as when rewinding is performed during playback, the first and second reel stands 12 and 13 are moved in the tape winding direction. , and playback starts in the fast forward direction.

However, since the tape is all wound in the fast forward direction, actual playback is not performed and the tape is stopped.

Thereupon, the tape end detection operation is performed, the switch 45 is closed, and the selection plunger 28 is energized, so that the playback progresses and the tape end is reached and playback is performed in the opposite direction by the same operation as described above. Reproduction is started in the reverse direction.

Next, to explain ejecting the cassette, when the eject lever (not shown) is operated, the lock plate 22 is first rotated counterclockwise by the eject lever.

After unlocking the head stand 24, the cassette is ejected and the power is turned off, ending the entire operation.

In the above embodiment, the power switch is turned on when the cassette is loaded.
The power switch can also be set separately and manually.

In addition, in order to remove tape slack, the first and second reel stands 1
2 and 13 in the winding direction, detecting that the tape slack has been removed and the rotation of the reel shaft portions 12c and 13c has stopped, the selection plunger 28 is energized to perform playback. This may be done by energizing the selection plunger 28 for a certain period of time after loading the tape (or by detecting the tension of the tape).

Further, in the above embodiment, the connecting gear 10a is used from the beginning.

Gears 3b and 4b of the first and second flywheels 3 and 4 and gears 12a and 13a of the first and second reel stands are connected by 11a.
Although shown as being connected to each other, it is also possible to connect them after the cassette is loaded.

In the above embodiment, when the reel stands 12 and 13 are rotated in the tape winding direction and the slack of the tape is removed,
In other words, the tape is under tension.

- Reel shaft portion 12c rotated by reel stands 12, 13;
, 13c to the reel stands 12, 13 and the reel shaft portion 12c,
It was stopped by a 7-reaction material such as felt installed between the tape 13c and Be careful not to wind up on one reel stand side (
Unless a friction material is provided (this state has the highest torque difference), it is not possible to detect tape stop and proceed to the next operation.

However, if a certain amount of friction is applied between the two, an unreasonable force will be applied to the tape at the end of the tape, and the tape may be cut.

Therefore, a normal amount of friction is applied between the reel stand and the reel shaft, and each reel stand is fed from the winding rotation direction only when removing tape slack.

It is conceivable that when the reel tries to rotate in the rotational direction, a stopper engages with the reel shaft of the reel stand and prevents the reel from rotating.

Specific examples thereof will be explained below with reference to FIGS. 13 to 15.

52 and 53 are located approximately at the center 52a of the chassis 1;

53a is an abbreviated ratchet plate to which is pivotally attached, one of which is the plate portion 12f of the reel stands 12, 13.

The plate portion 12f is located on the lower surface of the plate portion 13f and on the upper surface thereof.
, 13f, and a ratchet 52b corresponding to the engaging protrusions 12g and 13g formed on the lower surface.

53b is formed.

Note that the ratchet 52b. 53b is an engagement protrusion 12g when the reel stands 12, 13 rotate in the tape winding direction;
13g but is not engaged, and the reel stand 12,1
3 rotates in the tape supply direction, the engagement protrusion 12g
, 13g are engaged with the ratchets 52 b t s 3 b, and the plate portions 12 f of the reel stands 12 and 13.

It has a shape that prevents rotation of 13f.

Also, at the other end of the ratchet plate 52, 53 is an engaging pin 52c.
, 53c are formed, and the engagement pins 52c, 53c are formed.
A spring 54 is tensioned to apply a force such that the two are directed outward from each other.

Additionally, ratchet plates 52, 5 provided by springs 54
30 rotational force is regulated by stopper pieces 10e and 11e formed on the control levers 10 and 11.

Further, the engaging pins 52c, 53c enter the head stand 24 corresponding to the above-described engaging pins 52c, 53c, and in the latter half of the forward movement of the head stand 24, the ratchet plate 52.
A guide groove 24h for rotating the ratchet 53 and retracting the ratchets 52b and 53b from the trajectory of the engagement protrusions 12g and 13g.
, 24 i are formed.

Next, to explain the operation, in FIG. 13, when the head stand 24 is retracted and the reel stands 12 and 13 are rotated in the tape winding direction, the ratchet 52b
, 53b is the engagement protrusion 12g.

Since it is located on the rotational trajectory of 13g, the ratchet 52
b, 53b and the engaging protrusions 12gt13g are in contact with each other, but due to their shape, the ratchet plates 52 and 53 are in contact with the spring 54.
The ratchets 52b, 53b are rotated against the spring force of
moves from the trajectory of the engaging protrusions 12g and 13g.

Therefore, the plate portions 12f and 13f of the reel stand 12.degree. 13 continue to rotate (see the side of the reel stand 13 in FIG. 3).

Next, the slack in the tape is removed, and for example, if the amount of winding on the reel stand 13 side is small, the tape is removed from the reel stand 13.
Since it moves to the side, the reel stand 12 side becomes the supply side.

Therefore, since the engaging protrusion 12g comes into contact with the ratchet 52b and is engaged due to its shape, a force is applied to rotate the ratchet plate 52 clockwise. Since the rotation is prevented, as a result, the rotation of the plate portion 12f of the reel stand 12 is prevented (see the side of the reel stand 12 in FIG. 1.3).

As a result, the above-mentioned tape end detection device is activated and a transition is made to the playback state.

When the playback state is entered, the head stand 24 moves forward as shown in FIG. 14, so the engaging pins 52c and 53c of the ratchet plates 52 and 53 move into the guide groove 24h.

24i and this guide groove 24h.

Since the tips of the ratchet plates 24i form circular arcs that match the rotation loci of the ratchet plates 52 and 530, the ratchet plates 52 and 53 are rotated against the spring force of the spring 54, respectively, in the latter half of the forward movement of the head stand 24.

Therefore, the ratchets 52b and 53b are the engagement protrusions 12g.

Since it retreats from the trajectory of 13g, the engagement between the two disappears.

Of course, during this regeneration, one of the control levers 10 and 11 (the control lever 11 side in the figure) is selected by the aforementioned selection arm 4.
1, but the rotation is caused by the ratchet plate 53.
It will not be disturbed by.

Next, to fast forward or rewind in Figure 13,
It is necessary to prevent engagement between one of the ratchets and the engagement protrusion.

For example, when the tape is wound to the right, when the control lever 11 is rotated by the selection arm 41, the stopper piece 11e moves back as shown in FIG. 15, and the contact with the ratchet plate 53 is released. Therefore, the ratchet plate 53
is rotated by the spring force of the spring 54, so that the ratchet 53b is retracted from the trajectory of the engagement protrusion 13g.

As a result, the rotation of the reel stand 13 in the supply direction is not inhibited and the tape is wound up.

Further, since the winding in the opposite direction is similar, a description thereof will be omitted.

As described above, the present invention connects the first and second reel stands and the driving means in advance through the connecting means, and when tape slack occurs after loading the tape, the slack is immediately removed and fast forwarding is performed. Alternatively, when a rewinding operation is performed, the connection between one of the connecting means and the reel stand is released, and the tape is fast-forwarded or rewinded.

[Brief explanation of drawings]

Fig. 1 is a plan view of the entire tape recorder, Fig. 2 is a perspective plan view seen from the chassis, Fig. 3 is an exploded perspective view, Fig. 4 is a plan view of the head stand 1 driving part showing the playing state, Fig. 5 ，
Figure 6 is a plan view of the part that changes the running direction of the tape when the head is in an advanced state, Figure 7 is a central vertical sectional view of the reel stand, Figures 8 and 9 are perspective plan views of the tape end detection part, and Figure 10 is the left side. Fig. 11 is a plan view of the right direction playback state, Fig. 12 is a plan view of the state of fast forwarding to the left, and Figs. 13 to 15 are plan views of the tape being prevented from moving after tape slack has been removed. FIG. 1...Chassis, 2...Motor, 3,
4...First and second flywheels, io, il
...Control lever, 12, 13...1st
, second reel stand, 14°15... release plunger, 16, 17... operation lever, 20, 21
...Release lever, 22...Lock plate, 24...Head stand, 26, 27...
... Pinch roller unit, 28 ... Selection plunger, 29 ... Head stand advancement lever, 3
0... Control plate, 33... Rotating lever, 34... Rotating arm, 35...
Swing lever, 36...Control arm, 40...
...Slide lever, 41...Selection arm,
42... Unit mounting plate, 43... Large gear, 44... Cam plate, 45, 50, 51...
... Switch, 46 ... Switch control lever, 47 ... Pin support lever, 48 ...
...Detection arm, 49...Detection lever, 52,
53...Ratchet plate.

Claims (1)

[Claims] 1. A driving means that starts rotating when a cassette is loaded and the power is turned on, and the driving means and the first and second reel stands are connected in advance, and both of the reel stands are moved by the operation of the driving means. A drive mechanism for a tape recorder comprising a coupling means for rotating in the tape winding direction, and a coupling release means for fast forwarding or rewinding the tape by separating one of the coupling means from the drive means by operating a plunger or lever. .