JPS6145293B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a tape recorder drive mechanism suitable for use in, for example, a microcassette tape recorder.

In recent years, there has been a demand for tape recorders that are small, lightweight, portable, and capable of recording and playing back for long periods of time, and in response to this demand, for example, microcassette tape recorders have been developed. In such a tape recorder intended for miniaturization, the drive mechanism for running the tape must be compact and configured to operate reliably. To this end, it is desirable to reduce the number of parts and to organically combine the few parts so that the tape can run at a constant speed and at high speed.

The present invention has been made based on the above-mentioned circumstances, and an object of the present invention is to provide an extremely good tape recorder drive mechanism that has a simple structure, operates reliably, and can sufficiently contribute to downsizing of the tape recorder.

Hereinafter, an embodiment in which the present invention is applied to a microcassette tape recorder will be described in detail with reference to the drawings. In FIGS. 1 and 2, 11 is a main chassis of a microcassette tape recorder, which is installed in a cabinet (not shown). A substantially rectangular through hole 111 through which a pair of reel stands 12 and 13 are inserted is formed substantially in the center of the main chassis 11. The reel stands 12 and 13 are, for example, the main chassis 1.
They are rotatably supported by supporting pieces (not shown) protruding from 1 with a slight frictional force. In addition, the above reel stand 1
2 and 13 are provided with gears 14 and 15 coaxially, and the reel stands 12 and 13 and the gears 14 and 15
It is designed to rotate as a unit.

Here, a tongue piece 112 that projects inward of the through hole 111 is formed at the lower part of the through hole 111 formed in the main chassis 11 in FIG. A center pulley 16 is rotatably supported on the back side. As shown in FIG. 2, the center pulley 16 has a coaxial gear 17 that rotates integrally with the center pulley 16. 19 was inserted loosely,
A fitting 21 is attached to one end of the rotary shaft 19 via a washer 20, and the other end of the rotary shaft 19 is fitted into a through hole 113 formed in the tongue 112. It is rotatably supported.

Further, on the upper surface side of the tongue piece 112 in FIG.
A substantially cylindrical protrusion 114 is formed. After this protrusion 114 is inserted through a through hole 221 formed at one end of the switching drive plate 22, the mounting ring 23 is fitted thereto to rotatably support the switching drive plate 22. Here, the rotation of the center pulley 16 and gear 17 and the rotation of the switching drive plate 22 can be performed completely independently. Further, at the other end of the switching drive plate 22, a gear 24 that meshes with the gear 17 is rotatably supported. This gear 24 has a rotating shaft 25 loosely inserted into a through hole 241 formed at its center of rotation.
A rotating shaft 25 with a fitting 26 attached to one end of the rotary shaft 25
The other end of the switching drive plate 22 is fitted into the through hole 222 formed at the other end of the switching drive plate 22.
It is rotatably supported by 2. and,
This gear 24 operates according to the rotation of the switching drive plate 22.
It can selectively mesh with the gears 14 and 15 of the reel stands 12 and 13. Further, in the process of shifting the meshing state from the gear 14 to the gear 15 or vice versa, the gear 24 is transferred to both the gears 1 and 1, although the details will be described later.
4 and 15 are in mesh with each other.

Here, in the upper part of the main chassis 11 in FIG.
is formed. Furthermore, the main chassis 11
A head chassis (not shown) is installed in parallel with the recording/reproducing head 29, the erasing head 30, and the pinch lever 32 for rotatably supporting the pinch roller 31. For example, this head chassis operates a recording/reproducing head 29 and an erasing head 30 of a micro tape cassette (not shown) mounted on reel stands 12 and 13 in conjunction with the operation of a playback operator 33 provided protruding from one side of the cabinet. At the same time, the pinch lever 35 is pressed so that the pinch roller 31 is in contact with the tape and the capstan 2 is moved.
8 is moved in the direction in which it is pressed.

Rotational force is transmitted to the center pulley 16 and flywheel 27 from a pulley 35 fitted on a rotating shaft 341 of a motor 34 via a belt 36.

On the other hand, a rewind operator 37, a fast forward operator 38, and a record operator 3 are arranged in parallel with the playback operator 33.
9 and a stop operator 40 are provided. Among these operators 33, 37 to 40, the playback and fast-forward operators 33, 38 are respectively provided with switches S ₁ and S ₂ which are turned on at the operation position and turned off at the non-operation position. In addition, the rewind operator 3
7 is provided with a switch _S3 that switches to different contacts in its operating position and non-operating position.

Here, the motor 34 is controlled by a motor control circuit shown in FIG. ₃ which is interlocked with the on/off and switching of the switches _S1 to S3. That is, in FIG. 3, 41 is a battery housed in the cabinet of the microcassette tape recorder. The negative end of this battery 41 is grounded, and the positive end is connected to the recording/reproducing amplifier 42 and the above switch.
Grounded through _S1 . In addition, the battery 41
The positive end of is the first fixed contact of switch _S3 above.
_S31 and a fourth fixed contact _S34 . Furthermore, the second fixed contact of the switch _S3
S ₃₂ is grounded, and the third fixed contact S ₃₃ is grounded via the switch S ₂ , and the governor circuit 4
3 to the connection point between the recording/reproducing amplifier 42 and the switch _S1 . Common contacts S ₃₅ and S ₃₆ of the switch S ₃ are connected to both power supply terminals of the motor 34, respectively.

Note that the switch S ₃ has its common contacts S ₃₅ ,
Movable pieces S _{37 and} S ₃₈ are in constant contact with S 36, respectively.
are connected to the first and third fixed contacts S ₃₁ and S ₃₃ , respectively, when the rewind operator 37 is not operated,
When the rewind operator 37 is operated, it is switched to be connected to the second and fourth fixed contacts S ₃₂ and S ₃₄ , respectively.

The operation of the tape recorder drive mechanism configured as described above will be described below. First, when the fast-forward operator 38 is operated, the switch S ₂ is turned on, the switch S ₁ is turned off, and the movable pieces S ₃₇ and S ₃₈ of the switch S ₃ are connected to the first and third fixed contacts S ₃₁ and S ₃₃ Switch to each side. Then, of the two power supplies of the motor 34, the power supply end connected to the common contact S ₃₅ of the switch S ₃ becomes the positive side, and the other power supply end becomes the negative side, so the motor 34 moves in the positive direction (see Figure 1). Rotates at high speed in the direction of middle arrow A). Therefore, the center pulley 16 and the gear 17 are also rotationally driven in the same direction, and the gear 24 that meshes with the gear 17 rotates in the direction of arrow B as shown in FIG.

At this time, as shown in FIG.
is in a position where the gear 24 meshes with the gear 15 of the reel stand 13, the gear 15 is in the position indicated by the arrow C in the figure.
rotated in the direction

By the way, as mentioned earlier, the reel stand 12,1
3 is rotatably supported by the main chassis 11 with some frictional force. Therefore, when the gear 24 meshes with the gear 15 and rotates in the direction of the arrow B in FIG. 4, a rotational biasing force in the direction of the arrow D in the figure is applied to the switching drive plate 22. That is, gear 24 rotates gear 1 by its own rotation.
The meshing state with 5 is maintained. Therefore, the reel stand 13 is rotated in the same direction as the gear 15, and the tape is rapidly fed.

Next, when the playback operator 33 is operated, the switch _S1 is turned on and the switch _S2 is turned off in conjunction with this operation, and the movable pieces _{S37 and S33} of the switch S3 are moved to the first and third positions. They are held on the fixed contacts S ₃₁ and S ₃₃ sides, respectively. Then, the motor 34 is controlled by the governor circuit 43 and rotates in the same direction as the fast forwarding (direction of arrow A in FIG. 1) and at a lower rotational speed than during the fast forwarding.

At this time as well, the switching drive plate 2
2 is biased in the direction of meshing the gear 24 with the gear 15, and the tape runs at a constant speed. At this time, the recording/reproducing head 29 and the erasing head 30 come into contact with the tape, and the pinch roller 31 pinches the tape and presses against the capstan 28, so that the tape is played back. At the same time, the battery 41 is connected to the recording/reproducing amplifier 42.
The tape reproduction signal is amplified and reproduced by a speaker (not shown) or the like.

Note that in the recording state in which both the recording operator 39 and the playback operator 33 are operated, the operation can be explained in the same way as the above-mentioned playback state, except that a signal from a microphone (not shown) or the like is transmitted to the recording amplifier. The only difference is that recording is performed on the tape by the recording head 29 via 42.

Also, when the rewind operator 37 is operated, the movable pieces S ₃₇ and S ₃₈ of the switch S ₃ connect to the second and fourth fixed contacts.
Switches to the S ₃₂ and S ₃₄ sides, and both switches S ₁ and S ₂ are turned off. Then, of the two power supply terminals of the motor 34, the one connected to the common contact _S35 of the switch _S3 becomes the negative side, and the other power supply terminal becomes the positive side. Therefore, the motor 34 rotates at high speed in the opposite direction (direction of arrow E in FIG. 1). Then, the center pulley 16 and gear 17 are driven to rotate in the same direction,
The gear 24 meshing with the gear 17 rotates in the direction of arrow F as shown in FIG.

Here, as mentioned above, since the reel stands 12 and 13 are rotatably supported with some frictional force against the main chassis 11, the gear 24 is
Rotating in the direction means gear 2 relative to gear 15.
4 is an escape. Therefore, a rotational biasing force in the direction of arrow G is applied to the switching drive plate 22 to try to separate the gear 24 from the gear 15.

By the way, before the gear 24 is completely separated from the gear 15, it meshes with the gear 14 of the reel stand 12.
That is, the gear 24 is in a state where it meshes with the gears 15 and 14. Then, gear 2
The rotation in the direction of arrow F in 4 causes the gear 14 to bite, so when the gears 24 and 14 mesh, the gear 24 is pulled in the direction to completely mesh with the gear 14, as shown in FIG. It can be done. Thereafter, the gear 24 is kept in mesh with the gear 14 by its own rotation, and the gear 14 is rotated in the direction of arrow H. Therefore, the reel stand 12 is rotated in the same direction as the gear 14, and the tape is rewound.

Furthermore, the operation in which the gear 24 shifts from the gear 14 to the gear 15 when switching from the rewinding state to the fast forwarding state can be explained in the same manner as described above.

Therefore, according to the configuration of the above embodiment, the playback, fast forwarding, and rewinding operators 33, 38, 3
The rotation speed and rotation direction of the motor 34 are switched in conjunction with each operation of the motor 34.
The switching drive plate 22 is rotated and biased to the position shown in FIGS. 4 and 6 by the own rotational force of the gear 24 to which the rotational force is transmitted, and the tape is run. This structure requires only a small number of parts, and can contribute to making the tape recorder more compact as a whole. Further, since the gear 24 is kept in mesh with the gear 14 or 15 by its own rotation, the tape running is prevented from being interrupted due to the gear 24 inadvertently coming off from the gears 14 or 15 while the tape is running. and reliable operation can be obtained.

Furthermore, since the direction of rotation of the motor 34 is changed to perform fast forwarding and rewinding, even if the tape is directly switched from fast forwarding to rewinding or vice versa (direct change), excessive load is not applied to the tape, especially for micro It is suitable for use in tapes whose mechanical strength is not very high, such as tape cassettes.

It should be noted that the present invention is not limited to the above-mentioned embodiments, and can be implemented with various modifications without departing from the gist thereof.

Therefore, as described in detail above, according to the present invention, it is possible to provide an extremely good tape recorder drive mechanism that operates reliably with a simple configuration and can sufficiently contribute to downsizing of tape recorders.

[Brief explanation of the drawing]

1 and 2 are a top view and an exploded perspective view of essential parts showing an embodiment of a tape recorder drive mechanism according to the present invention, respectively, and FIG. 3 is a circuit configuration diagram showing a motor control circuit of the same embodiment. , and FIGS. 4 to 6 are explanatory diagrams of the operation of the same embodiment, respectively. 11... Main chassis, 12, 13... Reel stand, 14, 15... Gear, 16... Center pulley,
17... Gear, 18... Through hole, 19... Rotating shaft, 20...
Washer, 21... Mounting tool, 22... Switching drive plate, 2
3...Mounting cylinder, 24...Gear, 25...Rotating shaft, 2
6... Attachment, 27... Flywheel, 28... Capstan, 29... Recording/playback head, 30... Erasing head, 31... Pinch roller, 32... Pinch lever,
33... Regeneration operator, 34... Motor, 35... Pulley, 36... Belt, 37... Rewinding operator, 38...
Fast forward operator, 39...Record operator, 40...Stop operator, 41...Battery, 42...Recording amplifier, 43...Governor circuit.

Claims (1)

[Claims] 1 A motor control circuit that causes the motor to rotate at a constant speed in the forward direction, rotate at high speed in the forward direction, and rotate at high speed in the reverse direction in conjunction with the operations of the tape constant speed feed, fast forward, and rewind operators, and a pair of first and second gears that rotate, a rotating body to which the rotational force of the motor is transmitted, and a third gear that is connected to the rotating body so that rotational force can be transmitted at all times. The third
a switching drive member that selectively meshes the gear with the first gear or the second gear, and in the process of shifting the third gear from the first gear to the second gear or vice versa, A drive mechanism for a tape recorder, characterized in that a third gear is in mesh with the first and second gears.