JPH0973683A - Magnetic tape recording and reproducing device - Google Patents

Abstract

PROBLEM TO BE SOLVED: To make the manufacturing cost of the device low and to eliminate its noise. SOLUTION: A planetary gear 25 is engaged with either a 1st gear 5 or a 2nd gear 8 in accordance with a rotating direction of a motor. A reproducing capstan and a reverse reproducing capstan are always rotated by rotating the motor. Either a take-up reel base or a suppy reel base is selected and is driven to rotate. According to a turning position of the 1st gear 5, an operation mode for selecting a rotating position of a magnetic head and its heightwise position, a reel base to be driven, a driving speed of the reel base and a pinch roller to be moved to its capstan, etc., is set up. By rotating the 2nd gear 8 by the planetary gear 25, the magnetic head and the pinch roller are moved into their setting positions. By rotating the motor when the planetary gear 25 is positioned at a toothless part 8a of the 2nd gear, the capstans and either of the reel bases are driven to travel a magnetic tape in the reproducing or rewinding direction.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic tape recording / reproducing apparatus, and more particularly to reproducing, fast-forwarding, reverse reproducing,
The present invention relates to a magnetic tape recording / reproducing apparatus capable of performing mode switching such as rewinding and tape running with one motor as a drive source.

[0002]

2. Description of the Related Art Conventionally, in a recording / reproducing apparatus for a magnetic tape such as a compact cassette, a so-called tape recorder, reproduction,
One motor and one solenoid are used to perform mode switching such as fast-forwarding, reverse reproduction, rewinding, and tape running. Since such a tape recorder uses an expensive solenoid, the manufacturing cost is high, and the solenoid has a problem that the operation noise is large and noise is generated.

In order to solve the above problems, the fairness 7-92
The tape player proposed in Japanese Patent Publication No. 14 is provided with a drive gear integrally with a capstan rotated by a motor, and has a planetary gear that orbits around the drive gear according to the rotation direction of the drive gear while always meshing with the drive gear. It is located on the swing arm. The planetary gear meshes with one of the reel gears to drive the reel stand on the winding side or the supply side to rotate. The mode switching is performed by the planet gear rotating the mode switching gear in the middle of the orbit of the planet gear.

In the tape player of the first embodiment, the cam provided on the mode switching gear moves up and down the head base to which the magnetic head and the pinch roller are attached. And
The play mode (playback state) is set when the magnetic head contacts the magnetic tape and the pinch roller is pressed against the capstan, and the FF mode (fast-forward state is set when the magnetic head is separated from the magnetic tape and the pinch roller is separated from the capstan. ) Or REW (rewinding state). Further, the review mode is set when the magnetic head is in slight contact with the magnetic tape and the pinch roller is away from the capstan.
As the tape player of the second embodiment, a reproducing magnetic head and a reverse reproducing magnetic head are provided on the head base, the magnetic head is brought into contact with the magnetic tape instead of the review mode of the first embodiment, and the pinch roller is used. It is shown that the cap is pressed into contact with the capstan for reverse playback mode.

[0005]

[Problems to be Solved by the Invention]
The tape player of the first embodiment shown in Japanese Patent Publication No. 214 can perform the reproducing mode because it has only one magnetic head fixed to the head base, but cannot set the reverse reproducing mode. The tape player of the second embodiment is capable of a reproduction mode and a reverse reproduction mode, but has two magnetic heads fixed to the head base. In this case, a microcassette is used as the cassette half. The center of the exposed portion of the magnetic tape of the microcassette is held by the pinch rollers, and the magnetic heads can be brought into contact with the portions on both sides of the pinch roller. In the cassette half of the compact cassette, the pinch roller holding portions are arranged on both sides of the portion that comes into contact with the magnetic head, and it is difficult for the magnetic tape to come into contact with the two magnetic heads. Therefore, the fairness 7-9
In the method disclosed in Japanese Patent No. 214, in which the mode is switched by changing the position of the head base, reproduction and reverse reproduction cannot be performed using the cassette half of the compact cassette. Further, since the transmission mechanism for transmitting the rotation from the motor to the reel base is not used, the rotation speed of the motor has to be changed between fast-forwarding and reproduction, and the motor drive circuit becomes expensive. .

The present invention has been made in view of the above points, and an object of the present invention is to reproduce a magnetic tape recording / reproducing apparatus using a cassette half of a compact cassette by using one motor as a drive source. It is an object of the present invention to provide a means for performing mode switching such as fast-forwarding, reverse reproduction, rewinding, and tape running. Another object of the present invention is to provide a magnetic tape recording / reproducing apparatus in which the above-mentioned mode switching and tape running can be performed only by rotating one motor forward and backward without setting at two rotation speeds.

[0007]

In a magnetic tape recording / reproducing apparatus of the present invention, a planetary gear that meshes with a sun gear to which the rotation of a motor is transmitted and can orbit around the sun gear is provided with a first gear or a toothless portion. The capstan and either reel base are driven by the rotation of the motor when the planetary gear is positioned at the toothless portion of the second gear by engaging with any of the second gears of the magnet. Play the tape in the play or rewind direction. Further, the head elevating plate is moved up and down by the cam, and the magnetic head mounting plate slidably attached to the chassis and biased by the spring is moved up and down by the head elevating plate through the spring. Further, the head mounting is provided with a switching plate having a cam for moving one of the pinch rollers in the capstan direction and an engaging portion for rotating the magnetic head rotatably mounted on the magnetic head mounting plate by 180 °. Slidably attached to the plate.

A cam for raising and lowering the head elevating plate and a first protrusion for moving the switching plate are integrally provided on the second gear, and rotation of the motor is performed on one reel table and the other reel table. And a cam for driving a mode setting plate for setting a position at which the head mounting plate is driven, and for switching the power switching mechanism for switching and transmitting between
A cam that drives a second lever that moves the first lever that transmits the movement of the protrusion to the switching plate between a position that engages with the first protrusion and a position that does not engage the first protrusion, and the head lifting plate. A cam for driving the head elevating plate and a toothless portion of the second gear locks a second protrusion integral with the second gear at a position corresponding to the planetary gear. A cam for rotating a third lever for preventing rotation between a position for locking the second protrusion and a position for not locking the second protrusion;
Rotate with the gear.

In the above structure, the operation mode of the magnetic tape recording / reproducing apparatus is set by the rotation of the first gear.
That is, either one of the reel bases or the other reel base is selected as the reel base driven by the motor, and the position of the head mounting plate is set via the mode setting plate.
Further, the second lever is moved to either a position where the first lever is engaged with the first protrusion or a position where the first lever is not engaged.
Further, the rotation of the first gear at this time causes the third lever to rotate, and the locking of the second protrusion is released. Then, the second gear rotates because the elastic force of the spring for urging the magnetic head mounting plate is applied to the cam, the magnetic head mounting plate moves, and the tooth portion of the second gear engages with the planetary gear. Come to the position to meet.

After setting the operation mode in this way,
When the motor is rotated in the reverse direction, the planet gear orbits and meshes with the second gear. Then, as the second gear rotates, the head elevating plate ascends and the magnetic head mounting plate moves to the position set by the mode setting plate. Also, depending on the position of the second lever, the switching plate is moved or not moved by the first lever. By such a switching plate, either one of the pinch rollers is moved in the capstan direction, and the detection / recording portion of the magnetic head comes to a position where it contacts the A-side track or B-side track of the magnetic tape. When the second gear is rotationally driven by the planetary gear, the elastic force of the spring for urging the magnetic head mounting plate receives the torque in the planetary gear driving direction, but the third lever locks the second protrusion. Therefore, the toothless portion stops at the position corresponding to the planetary gear. In this state, the first gear and the second gear are not rotated by the motor, and the magnetic tape is run. And the first
The magnetic tape recording / reproducing apparatus operates in the mode set by the gear.

For example, in the play mode, the recording / reproducing portion of the magnetic head is in contact with the track on the surface A of the magnetic tape, and the pinch roller corresponding to the capstan for feeding the tape in the reproducing direction moves in the capstan direction. Has been made. The head mounting plate is largely moved in the direction of the magnetic tape, and the pinch roller is pressed against the capstan to bring the magnetic head into contact with the magnetic tape. The power switching mechanism is in a state of transmitting the rotation of the motor to one reel stand. In this state, when the motor rotates in the direction in which the planetary gear orbits in the second gear direction, the magnetic tape is sent by the capstan for sending in the reproducing direction and wound on one reel stand. Then, the track on the A side of the magnetic tape is recorded or reproduced.

In the reverse reproduction mode, the magnetic tape is sent by a capstan which is sent in the reverse reproduction direction and wound on the other reel stand. Then, the track on the B side of the magnetic tape is recorded or reproduced. That is, the pinch roller is pressed against the capstan sent in the reverse reproduction direction, the recording / reproducing portion of the magnetic head is in contact with the track on the surface B of the magnetic tape, and the rotation of the motor is transmitted to the supply reel stand.

In the fast forward and rewind modes, the head mounting plate is moved to a position where the pinch roller does not contact the capstan. In this case, if a speed change mechanism is provided, the tape can be fed or rewound at high speed with the number of rotations of the motor being the same as in the reproducing state.

[0014]

DESCRIPTION OF THE PREFERRED EMBODIMENTS An example of a magnetic tape recording / reproducing apparatus to which the present invention is applied will be described with reference to the drawings. FIG. 1 is an exploded perspective view of the magnetic tape recording / reproducing apparatus as seen from the front side of the chassis 1, and FIG. 2 is an exploded perspective view as seen from the back side of the chassis 1. The connection relationship is shown in lower case letters through both figures. Moreover, each X, Y, Z has shown the same direction.

A cassette is mounted on the surface of the chassis 1 shown in FIG. 1, but positioning pins for mounting are not shown. A reel stand 36a that winds the tape at the time of playing the B side and a reel stand 36b that takes up the tape at the time of playing the A side sandwiches the coil springs 35a and 35b, respectively.
It is attached to 4a and 34b while being prevented from rotating. The reel gears 34a and 34b are rotatably supported by shafts 1a and 1b provided upright on the chassis 1, respectively.

The magnetic head mounting plate 37 is supported by the chassis 1 so as to be slidable in the vertical direction, and is biased downward by a torsion coil spring 43 (not shown in FIG. 1) shown in FIG. . A head unit 48 is fastened to the magnetic head mounting plate 37. Head unit 48
A magnetic head 48a is attached via a rotary table 48b so as to be rotatable 180 ° about a vertical axis. Turntable 48
A gear 48c is fixed to the rotation shaft of b, and the gear 48c meshes with a gear 48d rotatably supported by the head unit 48. The gear 48d is biased by a torsion coil spring 48f. The recording detection unit and the writing unit of the magnetic head 48a are rotated by 180 ° to come into contact with the A side track or the B side track of the magnetic tape.

The switching plate 38 is supported by the magnetic head mounting plate 37 so as to be movable in the horizontal direction. The bent piece 38a of the switching plate 38 contacts the protrusion 48e of the gear 48d to rotate the magnetic head 48a. Further, the cam grooves 38b and 38c of the switching plate 38 rotate the pinch roller bases 46 and 46. That is, the pinch roller base 46 (see FIG.
(Only one of which is shown in the figure, but a symmetrical shape is provided on the left and right) is rotatably supported by shafts 1c and 1d that are erected on the chassis 1, and each is rotated by a pinch roller 46a. Supports freely. Also torsion coil spring 4
One end of 7 is engaged with the pinch roller base 46, respectively. The other ends of the torsion coil springs 47, 47 are engaged with the cam grooves 38b and 38c of the switching plate 38, respectively.
When the switching plate 38 moves to the left in FIG. 1, the right pinch roller base 46 is rotated in the direction of the capstan 30a shown in FIG. 2, and when the switching plate 4 moves to the right, the left pinch roller base 46 is moved. Is rotated in the direction of the capstan 31a.

The capstan 30a shown in FIG. 2 is integrated with the flywheel 30, and the boss 1e fixed to the chassis 1 is inserted through the capstan 30a to project on the chassis surface and rotatably supported. Similarly, the capstan 31a is integrated with the flywheel 31, and the boss 1f fixed to the chassis 1 is inserted through the capstan 31a to project from the chassis surface and rotatably supported. A belt (not shown) is stretched between the flywheels 30 and 31 and a pulley 32 of a motor 33 fixed to the chassis 1. The flywheels 30 and 31 are rotated in opposite directions by a motor 33. The capstan 30a is used for reproduction,
The capstan 31a is used for reverse reproduction.

A first gear 5 is rotatably supported on a shaft 1g provided upright on the rear surface of the chassis 1 shown in FIG.
A second gear 8 having a toothless portion 8a is rotatably supported on a shaft 1h provided upright on the back surface of the chassis 1. A planetary gear 25 can be meshed with these gears. The planetary gear 25 is rotatably supported by a shaft erected on the swing arm 24, and is always connected to the small gear (sun gear) of the two-stage gear 26 supported coaxially with the swing arm 24 (shaft 1j). I'm in mesh. The large gear of the two-stage gear 26 meshes with the gear 27, and the gear 27 meshes with the gear 28, the gear 28, a pulley 29 that is not rotated, and a belt (not shown) between the pulley 32 of the motor 33. The rotation of the motor 33 is always transmitted to the two-stage gear 26 (sun gear). Due to the frictional force, the planetary gear 25 rotates together with the swing arm 24 in the rotation direction of the sun gear, and meshes with the large gear of the first gear 5 shown in FIG. 5 or with the second gear 8 shown in FIG. It is in a suitable state.

The speed change cam 7 provided with the gear 6 and the gear 7a is rotatably supported by a shaft standing on the rear surface of the chassis 1. The gear 6 meshes with the small gear of the first gear 5 and the gear 7 a, and the shift cam 7 rotates at the same rotational speed as the first gear 5.

The shape of the first gear 5 is shown in FIG. FIG. 3A is a side sectional view, and FIGS. 3B and 3C.
And (d) are AA and BB in FIG. 3A, respectively.
It is a CC sectional view. The first gear 5 has a cam 5
a, 5b and 5c are formed. The reference numeral attached to each cam indicates each mode of the position where each contact, which will be described later, contacts. 4A and 4B show the shape of the speed change cam 7. Reference numerals attached to the respective positions of the cam indicate the same modes as those in FIG. 4C and 4D show the shape of the second gear 8. As shown in the figure, the second gear 8 has a toothless portion 8a,
Protrusions 8b and 8c and a cam 8d are provided.

The head lifting plate 4 is provided on the back surface of the chassis 1 so as to be movable in the vertical direction. A tension coil spring 40 is hung between the bent piece 4 a of the head elevating plate 4 protruding toward the front side of the chassis and the magnetic head mounting plate 37. The bent piece 4b of the head lift plate 4 contacts the cam 8d of the second gear 8. The spring pressing lever 3 is a head lifting plate 4
Movably in the left-right direction. One of the bending pieces 3a and 3b provided on the spring pressing lever 3 presses one end of a torsion coil spring 18 attached to an arm 15 described later. The mode setting plate 2 is provided on the back surface of the chassis 1 so as to be movable in the left-right direction, and is biased by a tension coil spring 39 arranged on the front side of the chassis 1. That is, the bent piece 2c of the mode setting plate 2 is the first gear 5
Is pressed against the cam 5a. A shaft 2a provided upright on the mode setting plate 2 is inserted through a vertical groove 3c of a spring pressing lever 3. The groove 2b of the mode setting plate 2 is provided with the magnetic head mounting plate 37.
It comes into contact with the bent piece 37a and regulates the position of the magnetic head mounting plate 37.

The arm 15 is rotatably supported by a shaft 1k standing on the rear surface of the chassis 1 via a boss 15a. A shaft 15c erected on the arm 15 rotatably supports a gear 16. The shaft 17 rotatably supported by the boss 15b of the arm 15 has a gear 17 and a two-stage gear 2.
0 is attached. The gear 16 and the gear 17 mesh with each other. The bending piece 3a or 3b of the mode setting plate 3 pushes one end of the torsion coil spring 18 to attach the torsion coil spring 18 attached to the arm 15 to tilt the arm 15 so that the gear 16 meshes with the reel gear 34a or the gear 17 forms the reel gear 34b. Mesh with each other.

A shaft 1m erected on the rear surface of the chassis 1 is inserted through the holes of the speed change lever 13 and the arm 15 to support the speed change gear 21 rotatably and axially movably.
3 is rotatably supported. Transmission gear 21 and pulley 2
Reference numeral 3 denotes a rotation stop, and a coil spring 22 fitted between them presses the transmission gear 21 against the transmission lever 13. The speed change lever 13 is axially movably supported by a shaft 1n provided upright on the rear surface of the chassis 1.
a is in contact with the speed change cam 7, and is moved in the axial direction by the speed change cam 7. The large gear of the transmission gear 21 is the two-stage gear 20.
The small gear of the transmission gear 21 can mesh with the large gear of the two-stage gear 20. A belt (not shown) is hung between the pulley 23 and the pulley 32 of the motor 33.
Is always transmitted. As shown in FIGS. 13 and 14, the rotation of the pulley 23 is changed in speed by the rotation position of the speed change cam 7 and transmitted to the gear 17. FIG. 14A shows a reproduction or reverse reproduction state. At this time, the gear 17
Is driven to rotate at a low speed. Further, FIG. 14B shows a fast-forward or rewind state. At this time, the gear 17 is rotationally driven at high speed.

The first lever 9, the second lever 10 and the third lever 11 are rotatably supported by shafts provided upright on the rear surface of the chassis 1, respectively. The first lever 9 is biased counterclockwise by the tension coil spring 14, and the third lever 11 is biased clockwise by the torsion coil spring 12. The second lever 10 is a torsion coil spring 41 shown in FIG.
It is urged counterclockwise by. (Torsion coil spring 41
Are not shown in FIG. ) End 9 of the first lever 9
a is engageable with the arcuate convex portion 8b of the second gear 8, the end portion 9b of the first lever 9 contacts the end portion 10b of the second lever 10, and the end portion 9b of the second lever 10 The end 10a is in contact with the cam 5c of the first gear. The end portion 9b of the first lever 9 is erected on the switching plate 38, and can engage with a shaft 38d protruding on the back surface side of the chassis 1. The end 11a of the third lever 11 is in contact with the cam 5b of the first gear, and the end 11b of the third lever 11 is in contact with the protrusion 8c of the second gear 8. .

The position of the mode setting plate 2 is detected by the micro switch 45 and the photo interrupter 44 shown in FIG. (Micro switch 45 and photo interrupter 44
Are not shown in FIG. That is, the mode setting plate 2 operates the micro switch 45 at the home position. Further, after that, the photo interrupter 44 detects the holes 2d, 2d ... Of the mode setting plate 2 so that the position of the mode setting plate 2 is detected.

Next, the operation of the magnetic tape recording / reproducing apparatus will be described with reference to FIGS. By rotating the motor 33 in the normal direction, the planetary gear 25 is moved to the first position as shown in FIG.
The reproduction mode is set when the first gear 5 is engaged with the gear 5 and the first gear 5 is rotated in the clockwise direction to bring the code F into a position corresponding to the mode setting plate 2. At this time, as shown in FIG. 11A, the deep portion of the groove 2b of the mode setting plate 2 corresponds to the bent piece 37a of the magnetic head mounting plate 37. Also,
As shown in FIG. 12A, the spring pressing lever 3 is at a position where the bent piece 3 a is engaged with one end of the torsion coil spring 18. Further, the third lever 11 is rotated in the clockwise direction so that the end portion 11b locks the protrusion 8c of the second gear 8. Further, the first lever 9 is rotated counterclockwise by the clockwise rotation of the second lever 10, and the end portion 9a of the first lever and the protrusion 8b of the second gear 8 are It is in a position where it does not engage. Further, the shift cam 7 is in a state of driving the gear 17 at a low speed as shown in FIGS. 13 and 14 (a).

When the motor 33 is rotated in the reverse direction in this state, the planet gear 25 comes into mesh with the second gear 8 as shown in FIG. 10, and the second gear 8 is rotated counterclockwise. The cam 8d of the second gear raises the head lift plate 4. Immediately before the protrusion 8c of the second gear is locked to the end portion 11b of the lever 11, the planet gear 25 comes to correspond to the toothless portion 8a, and the pressure of the head elevating plate 4 causes the second gear to reverse. Although it rotates by receiving the torque in the clockwise direction, when the projection 8c is locked to the end portion 11b of the lever 11, the second gear stops. The motor 33 continues to rotate, but the planetary gear 25
Corresponds to the toothless portion 8a, so the second gear does not rotate. This state is a reproduction state. At this time, FIG.
As shown in (b), the bent piece 37a of the magnetic head mounting plate 37 is inserted into one deep portion of the groove 2b so that the magnetic head comes into contact with the magnetic tape. Further, the switching plate 38 is located at the left side when viewed from the front side of the chassis 1, the pinch roller is pressed against the capstan 30a for feeding the magnetic tape in the A-side reproducing direction, and the magnetic head 48a is on the A-side of the magnetic tape. Detect the signal. Further, as shown in FIG. 12B, the arm 15 rotates counterclockwise when viewed from the rear surface of the chassis 1, the gear 16 meshes with the reel gear 34b, and the take-up reel stand 36b moves in the tape take-up direction. Is rotated. In this way, the side A of the magnetic tape is reproduced.

The mode setting is first set by the forward rotation of the motor 33.
This is done by rotating the gear 5 of the magnetic head, but during the mode switching, the third lever 11 is rotated counterclockwise as shown in FIG. 9, the end 11b is disengaged from the projection 8c, and the magnetic head mounting plate is released. The elastic force of the spring biasing 37 applies a torque to rotate the second gear 8 counterclockwise, so that the second gear 8 rotates to the position shown in FIG.

FIG. 6 shows a state in which the reverse reproduction mode is set by the rotation of the motor 33. At this time, the mode setting plate 2 moves to the right from the position shown in FIG. 11A, and the deep portion on the left side of the groove 2b corresponds to the bent piece 37a of the magnetic head mounting plate 37. Further, the spring pressing lever 3 moves to the right from the position shown in FIG. 12A, and the bending piece 3b is in a position where it engages with the other end of the torsion coil spring 18. Further, the third lever 11 is rotated in the clockwise direction so that the end portion 11b locks the protrusion 8c of the second gear 8. Further, the first lever 9 is rotated clockwise by the counterclockwise rotation of the second lever 10, and the end portion 9a of the first lever and the protrusion 8b of the second gear 8 are It is in the engaged position. Further, the shift cam 7 is in a state of driving the gear 17 at a low speed as shown in FIG.

When the motor 33 is rotated in the reverse direction in this state, as shown in FIG. 7, the planet gear 25 meshes with the second gear and the second gear 8 is rotated counterclockwise. The cam 8d of the second gear raises the head lift plate 4. Further, the protrusion 8b rotates the first lever 9 in the clockwise direction, and the switching plate 38 is moved to the right when viewed from the front side of the chassis 1. Immediately before the protrusion 8c of the second gear is locked to the end 11b of the lever 11 as shown in FIG. 8, the planetary gear 25 comes to correspond to the toothless portion 8a, and the pressure of the head lifting plate 4 causes The second gear rotates by receiving counterclockwise torque, but when the protrusion 8c is locked to the end 11b of the lever 11, the second gear stops. The motor 33 continues to rotate, but the second gear does not rotate because the planetary gear 25 corresponds to the toothless portion 8a. This state is the reverse reproduction state. At this time, the bent piece 3 of the magnetic head mounting plate 37
7a enters the other deep portion of the groove 2b and the magnetic head comes into contact with the magnetic tape. Further, the shaft 38d of the switching plate 38 is inserted in the recess on the right side of the hole 1p of the chassis 1 as viewed from the front side, and the capstan 31 for sending the magnetic tape in the B-plane reproducing direction.
The pinch roller is pressed against a, and the magnetic head 48a
Is rotated so as to detect the signal on the B side of the magnetic tape. Further, the arm 15 rotates clockwise when viewed from the rear surface of the chassis 1, the gear 17 meshes with the reel gear 34a, and the supply reel stand 36a rotates in the tape winding direction. In this way, the B side of the magnetic tape is reproduced.

When setting the fast-forward mode, the motor 3
By normal rotation of No. 3, the sign FF of the cam 5a is set to the position corresponding to the mode setting plate 2 as shown in FIG. 11 (c). At this time, the spring pressing lever 3 is moved to the position shown in FIG.
It moves to the left from the position shown in (a), but the bent piece 3a
Is in a position to engage the torsion coil spring 18. Motor 3
When 3 is reversed, the magnetic head is raised, but FIG.
As shown in (d), the bent piece 37a of the magnetic head mounting plate 37 is inserted into the shallow portion of the groove 2b so that the magnetic head comes into light contact with the magnetic tape. At this time, the pinch roller does not contact the capstan. The arm 15 rotates counterclockwise as shown in FIG. 12D, and the gear 16 moves to the reel gear 34b.
One of the reel bases 36b that meshes with is rotated in the tape winding direction. Further, the shift cam 7 is in a state of rotating the gear 17 at a high speed. Further, the magnetic head 48a is at a position for detecting a signal on the A side of the magnetic tape. In this way, the A-side track of the magnetic tape is sent at high speed in the reproducing direction. The search can be performed by making the magnetic head detect the presence or absence of a signal.

Codes RE (F), FF (R) of the cam 5a,
By setting RE (R) at a position corresponding to the mode setting plate 2, it is possible to set each mode. In the RE (F) mode, the magnetic head 48a is in a position to detect the signal on the A side of the magnetic tape, the pinch roller is away from the capstan, and the magnetic tape is wound at high speed by the other reel stand 36a. . In the FF (R) mode, the magnetic head 48a is at a position for detecting a signal on the B side of the magnetic tape, the pinch roller is away from the capstan, and the magnetic tape is wound at high speed by the other reel stand 36a. . In the RE (R) mode, the magnetic head 48a is at a position for detecting a signal on the B side of the magnetic tape, the pinch roller is away from the capstan, and the magnetic tape is wound at high speed by the reel stand 36b. .

FIG. 16 shows a modification of the above embodiment. In this example, instead of detecting the hole 2d by the photo interrupter 44, the first gear 5 is provided with reflecting plates 5d, 5d, ... Corresponding to each mode, and the reflecting plate 5d is detected by a photo reflector. The setting status of each mode is detected. If the width of one of the reflectors 5d is made wider than the other, so that the position of the home position is detected based on the difference in detection time, the micro switch 45 in the previous embodiment becomes unnecessary.

[0035]

According to the magnetic tape recording / reproducing apparatus of the present invention, in a magnetic tape recording / reproducing apparatus using a cassette half of a compact cassette, reproduction and fast-forwarding are performed by using one motor as a drive source without using a solenoid.
Since mode switching such as reverse reproduction and rewinding and tape running are performed, no noise is generated and the manufacturing cost is reduced. Also, since the motor can be fast-forwarded and reproduced at a constant speed, the motor drive circuit becomes simple.

[Brief description of drawings]

FIG. 1 is an exploded perspective view showing a front side portion of a chassis of a magnetic tape recording / reproducing apparatus to which the present invention is applied.

FIG. 2 is an exploded perspective view showing a back side portion of a chassis of the magnetic tape recording / reproducing apparatus.

FIG. 3 is a sectional view showing components of the magnetic tape recording / reproducing apparatus.

FIG. 4 is a plan view and a sectional view showing components of the magnetic tape recording / reproducing apparatus.

FIG. 5 is a rear view showing a part of the magnetic tape recording / reproducing apparatus as seen through.

6 is a diagram showing another state of the portion shown in FIG.

7 is a diagram showing still another state of the portion shown in FIG.

FIG. 8 is a diagram showing still another state of the portion shown in FIG.

9 is a diagram showing still another state of the portion shown in FIG.

10 is a diagram showing still another state of the portion shown in FIG.

FIG. 11 is a rear view showing a part of the magnetic tape recording / reproducing apparatus.

FIG. 12 is a rear view showing a portion of the magnetic tape recording / reproducing apparatus.

FIG. 13 is a rear view showing a portion of the magnetic tape recording / reproducing apparatus.

FIG. 14 is a side sectional view of a portion shown in FIG.

FIG. 15 is an exploded perspective view showing a part of the magnetic tape recording / reproducing apparatus.

FIG. 16 is a rear view showing components in a modified example of the magnetic tape recording / reproducing apparatus.

[Explanation of symbols]

1 chassis, 1a, 1b, 1c, 1d axes, 1e, 1
f boss, 1g, 1h1j axis, 1m, 1n axis, 1p
Hole 2 mode setting plate, 2a axis, 2b groove, 2c bent piece, 2d hole 3 spring pressing lever, 3a, 3b bent piece, 3c vertical groove 4 head lift plate, 4a, 4b bent piece 5 first gear 5a, 5b, 5c cam, 5d reflector 6 gear 7 gear change cam 8 second gear, 8a toothless portion, 8b, 8c protrusion, 8
d cam 9 first lever, 9a, 9b end portion 10 second lever, 10a, 10b end portion 11 third lever, 11a, 11b end portion 12 torsion coil spring 13 speed change lever, 13a tongue piece 14 tension coil spring 15 arm , 15a, 15b Boss, 15c Shaft 16, 17 Gear 18 Torsion coil spring 19 Shaft 20 Two-step gear 21 Speed change gear 22 Coil spring 23 Pulley 24 Swing arm 25 Planetary gear 26 Two-step gear 27 Gear 28 Gear 29 Pulley 30 Flywheel, 30a Capstan 31 Flywheel, 31a Capstan 32 Pulley 33 Motor 34a, 34b Reel gear 35a, 35b Coil spring 36a, 36b Reel stand 37 Magnetic head mounting plate, 37a Bending piece 38 Switching plate, 38a Bending piece, 38b, 38c
Cam groove, 38d Shaft 39, 40 Tension coil spring 41, 42, 43 Torsion coil spring 44 Photo interrupter 45 Micro switch 46 Pinch roller base, 46a Pinch roller 47 Torsion coil spring 48 Head unit, 48a Magnetic head, 48b
Turntable, 48c gear, 48d gear, 48e shaft, 48f torsion coil spring

Claims (2)

[Claims] 1. A planetary gear capable of orbiting around a sun gear, which meshes with a sun gear to which rotation of a motor is transmitted, is engaged with either a first gear or a second gear having a toothless portion to form a planetary gear. The rotation of the motor when the gear is located at the toothless portion of the second gear drives the capstan and one of the reel bases to run the magnetic tape in the reproducing or rewinding direction and slide it on the chassis. A magnetic head mounting plate that is movably mounted and biased by a spring is moved up and down by a head lifting plate via a spring, and one of the pinch rollers is moved in the capstan direction. 1 magnetic head attached freely
A switching plate having an engaging portion for rotating by 80 ° is slidably attached to the head mounting plate, and a cam for moving the head lifting plate up and down and a first projection for moving the switching plate are provided for the second. A mode setting plate provided integrally with the gear to switch a power switching mechanism for transmitting the rotation of the motor by switching between one reel stand and the other reel stand and setting a position at which the head mounting plate is driven. A cam for driving and a first for transmitting the movement of the first protrusion to the switching plate
A cam that drives a second lever that moves the lever between a position that engages the first protrusion and a position that does not engage the first protrusion, and a cam that drives the head lift plate raises the head lift plate and The third lever that locks the second protrusion integral with the second gear and blocks the rotation of the second gear is provided at the second lever at a position where the toothless portion of the second gear corresponds to the planetary gear. A magnetic tape recording / reproducing apparatus configured to rotate a cam that rotates between a position where a protrusion is locked and a position where the protrusion is not locked by the first gear. 2. A magnetic tape recording / reproducing apparatus according to claim 1, wherein a gear changing mechanism for transmitting the rotation of the motor to the capstan and one of the reel stands by gears is driven by the first gear.