KR100247295B1 - Video tape recorder - Google Patents

Abstract

The present invention is to provide a video tape recorder capable of relieving the relaxation to occur on the tape without using a dedicated motor when switching from the playback mode to the rewind playback mode. The tension coil spring 38 which connects between the supply side reel gears 32, and an arc to the supply side reel gear 32 before releasing the braking force of the supply side reel shaft 26 in preparation for switching from regeneration mode to rewind regeneration mode. It is provided with a relay gear which is connected to the supply side reel gear 32, and is provided with a relay gear which makes it move and engages, and a rotational force can be transmitted from the capstan motor to the supply side reel gear 32. By rotating the supply side reel gear 32 to the rewind side independently of the supply side reel shaft while resisting the elastic bearing force of the tension coil spring 38, and then the tension of the tape and braking of the supply side reel shaft 26 At the same time the supply side is released as soon rilchuk 26. rewinds the tape is rotated by receiving rotation as much as the urging force of the tension coil spring 38, the reel gear 32 are advancing in advance.

Description

Video tape recorder

1 is a schematic perspective view showing the inside of a video cassette tape recorder.

2 is a plan view showing an operating state of each part immediately after the cassette is loaded.

3 is a cross-sectional view showing a connection structure between a supply side reel shaft and a supply side reel gear.

4 is a cross-sectional view of a masonry provided on the lower surface of the reel disk of the supply side reel shaft.

5 is a perspective view showing a power transmission system to a mode switching device and each reel gear.

FIG. 6 is a plan view showing a state where the state of FIG.

FIG. 7 is a plan view showing the transition of the preparation step to the rewind regeneration mode in the state of FIG.

8 is a plan view showing the final phase of the preparation step in the rewind regeneration mode in the state of FIG.

* Explanation of symbols for the main parts of the drawings

26: supply side reel shaft 28: rewind side reel shaft

30: reel disk 32: supply side reel gear

38: tension coil spring (elastic support means) 56: brake band

58: tension arm 80: cam plate (moving member)

108: control link 113: gear plate

114: center gear 126: feed side relay gear

124: capstan motor

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a video tape recorder, and more particularly, to a video tape recorder having improved tape rewinding during rewind playback.

The video tape recorder has a rewind playback function to facilitate searching in the playback mode of the tape. Rewinding of the tape in this rewind regeneration mode is performed, for example, by rotating the supply side reel shaft to the rewind side by a dedicated motor. Alternatively, change the power transmission path so that the rotation of the capstan motor can be transmitted to the supply side reel shaft instead of the rewind side reel shaft, and then reverse the capstan motor, thereby returning the tape to the capstan and the pinch roller and simultaneously supplying the reel shaft to the supply shaft. It is rotating to the rewind side.

In this rewind regeneration mode, as well as the braking force of the band brake applied to the supply side reel shaft during the regeneration mode, the tension given by the tension arm to the tape headed to the head cylinder is released, respectively.

However, when the tension arm is returned to release the tension of the tape prior to switching from the rewind mode to the rewind mode, the running path becomes shorter than the length of the tape itself between the supply side reel shaft and the head cylinder, and the tape is relaxed. do. This loosening of the tape causes a poor winding of the tape to the head cylinder, that is, a poor adhesion of the tape to the magnetic head, thus disturbing the reproduced image and damaging stable rewinding.

Therefore, in a video tape recorder in which the supply side reel shaft is rotatable with a dedicated motor, the supply side reel shaft is rotated to the rewind side in conjunction with the retraction of the tension arm. In this case, however, it is not necessary to control the drive timing of the dedicated motor, but by adding the dedicated motor, the configuration of the electric circuit of the entire video tape recorder is complicated, and the cost is increased.

On the other hand, in the video tape recorder which rotates the supply side reel shaft to the rewinding side by the capstan motor as described above, a dedicated motor is not used separately from the capstan motor, thereby simplifying the construction of the electric circuit system. Is also advantageous. However, because of the configuration, the supply side reel shaft cannot be rotated to the rewind side independently of the capstan, so that the tape is inevitably released at the time of switching to the rewind regeneration mode.

The present invention has been made in accordance with the above-described circumstances, and its object is to provide a simple configuration without using a dedicated motor when switching from the regeneration mode to the rewind mode, and independent of the capstan when the tension of the tape is released. The present invention provides a video tape recorder which rotates the supply reel shaft to the rewind side so that no loosening occurs in the tape.

The present invention is applied to a video tape recorder which does not use such a dedicated motor.

The video tape recorder of claim 1 which achieves the above object,

(1) tension means for applying a tension to the tape directed to the head cylinder during the regeneration mode of the tape and releasing the tension of the tape in the preparation step when switching from the regeneration mode to the rewind regeneration mode;

(2) a braking means for applying a predetermined braking force to the supply side reel shaft in the regeneration mode, but releasing the braking force in association with the release of the tension means;

(3) A power transmission path between the capstan motor and the supply side reel shaft in the preparation step, having a supply side reel gear coaxial with the supply side reel shaft and rotatable to engage with each other, and a relay gear rotatable under the rotational force of the capstan motor. It has a power transmission means for connecting. The relay gear is engaged with the supply side reel gear by rotating in the stationary state before the braking force of the supply side reel shaft is released.

In addition, the tape recorder,

(4) elastic support means for rotating and elastically supporting both of the supply side reel shaft and the supply side reel gear in opposite directions;

(5) When the supply-side reel gear and the relay gear are engaged, the supply-side reel gear is subjected to the braking force of the braking means by the relay gear against the rotational elastic support force of the elastic support means, and is prescribed to the rewinding side with respect to the supply-side reel shaft in the stopped state. Advance means are provided to rotate independently by the rotation angle of.

In particular, the advancing means is configured to impart an arc motion to the relay gear and collide with the supply side reel gear when the relay gear is engaged with the supply side reel gear as shown in claim 2.

The video tape recorder of claim 3 includes a movable member on the power transmission means for moving the rewinding regeneration mode from the regeneration mode position in accordance with the switching to the rewinding regeneration mode, wherein the advance means is rotatably supported in the vicinity of the movable member. And a link means for connecting the gear plate and the ging plate to the movable member, and the relay gear is provided at one end of the gear plate. The link means is configured to rotate the gear plate in association with this movement when the movable member moves from the regeneration mode position to the rewind regeneration position.

The video tape recorder of claim 4 is provided with a tension coil spring for connecting between the supply side reel shaft and the supply side reel gear as its elastic support means.

According to the video tape recorder of claim 1, when switching from the playback mode to the rewind playback mode, the relay gear is first moved to engage the relay gear with the supply side gear. Then, the gear end of the relay gear is engaged with the gear end of the supply side gear. By the engagement of these gears, the relay gear receives the braking force and rotates the supply side reel gear to the rewind side by a predetermined rotational angle with respect to the supply side reel shaft in a stationary state.

Thereafter, the tension of the tape by the tension means is released and in conjunction with this the braking force of the supply side reel shaft by the brake means is released. Then, the supply side reel shaft is rotated to the rewind side by receiving the elastic support force of the elastic support means and winds the loose portion of the tape.

In particular, according to the video tape recorder of claim 2, the relay gear is circularly moved to collide with the supply side reel gear, which is pushed toward the winding side of the supply side reel gear while being engaged with the supply side reel gear.

According to the video tape recorder of claim 3, when the movable member of the power transmission means moves from the regeneration mode position to the rewind regeneration mode position, the gear plate is rotated by the link means in association with the movable member, and the circular motion of the relay gear is performed. Is given.

According to the video tape recorder of claim 4, when the supply side gear is rotated to the winding side independently with respect to the supply side reel gear shaft, the tension coil spring connecting the supply side reel shaft and the supply side gear is extended. Then, the braking force is released and at the same time, the supply side reel shaft receives the elastic support force and is rotated to the rewinding side with the contraction of the tension coil spring.

Referring to FIG. 1, the internal structure of a video tape recorder is schematically illustrated. The video tape recorder has a main chassis 2 arranged in a chassis (not shown), and a cassette loading device 4 is disposed on the front portion of the main chassis 2. The cassette loading apparatus 4 has a cassette holder 6 which is open toward the front of the video tape recorder, and the cassette can be inserted and detached through the cassette holder 6. The cassette inserted into the cassette holder 6 is drawn inward, then lowered toward the main chassis 2 and positioned at the loading position.

The inner part of the main chassis 2 has a head cylinder 8 having a magnetic head, a capstan 10, a pinch roller 12 cooperating with the capstan 10, and a part of the mode switching device 14, Braking motors 16, which are driving sources thereof, are disposed respectively.

1 shows an erasing head 18 disposed between the cassette and the head cylinder 8 as seen from the winding-travel direction of the tape in the loaded cassette, and between the head cylinder 8 and the cassette. An audio control head 20 is shown. 2, the guide rollers 22 which guide the running of the tape are also shown. Also, the double dashed line in the second diagram shows the outline of the loaded cassette (C).

2 shows a supply side reel shaft 26 and a winding side reel shaft 28 mounted in the reel holes of the loaded cassette C. As shown in FIG. These reel shafts 26, 28 protrude in the loading device 4 from the main chassis 2. In addition, the main chassis 2 is omitted in the second drawing.

The supply side reel shaft 26 has the reel disk 30 integrally under it. The supply side reel gear 32 is arranged coaxially under the reel disk 30 as shown in FIG. The supply side reel shaft 26 and the supply side reel gear 32 are rotatably supported by the gear shaft 34 provided in the main chassis 2, and engage and rotate as described later.

The reel disk 30 and the supply side reel gear 32 are connected to each other by a tension coil spring 38. As can be seen in FIG. 3, one end of the tension coil spring 38 is connected to the pin 40 protruding from the lower surface of the disk 30, and the other end of the tension coil spring 38 protrudes from the upper surface of the supply side reel gear 32. Is connected to (42).

More specifically, the tension coil spring 38 extends inside the arc-shaped spring storage chamber 44 secured between the reel disk 30 and the supply side reel gear 32. In addition, the spring storage chamber 44 is composed of a protrusion 46 protruding from the bottom surface of the reel disk 30 to form a downward arc-shaped groove portion and an upward arc-shaped groove portion formed on the upper surface of the supply side reel gear 32. It is.

As can be seen in FIG. 4, the pin 42 on the supply side reel gear 32 side is fitted into the arc groove 50 formed at the upper end thereof in the protrusion 46, and is inserted into the arc groove 50. As shown in FIG. It can be moved along. In the state shown in FIG. 4, the pin 42 is located in the one end of the arc groove 50, ie, the clockwise end. In this case, the tension coil spring 38 supports both the supply side reel shaft 30 and the supply side reel gear 32 in a rotational elasticity opposite to each other. The reel disk 30 rotates integrally with the supply side reel gear 32 by engaging the pin 42 on the supply side reel gear 32 side with the end of the arc groove 50.

Moreover, unlike the supply side reel shaft 26, the winding side reel shaft 28 forms the reel disk 52 integrally in the lower part.

The brake band 56 is rotated on the reel disk 30 of the supply side reel shaft 26 on its right half circumferential surface. One end of the brake band 56 is fixed to the pin 57 provided in the main chassis 2 and the other end thereof is connected to the tension arm 58 via the pin 60.

The tension arm 58 is disposed on the left side of the supply side reel shaft 26 as shown in FIG. The base end of the tension arm 58 is rotatably supported by the main chassis 2 via the support shaft 62, and the other end thereof extends toward the head cylinder 8 described above. The pin 60 protrudes upward from the upper surface of the tension arm 58 beyond the main chassis 2.

The main end of the main chassis 2 and the tension arm 58 are connected to each other by a tension coil spring 64. This tension coil spring 64 is rotationally elastically supported in the direction of separating the tension arm 58 counterclockwise, that is, the direction away from the supply side reel shaft 26, as shown in FIG. On the other hand, the tip portion of the tension arm 58 is bent to the left side as seen in FIG. 2, and the tension pin 66 protrudes upward from the tip end thereof.

An interlocking plate 68 is disposed between the tension arm 58 and the supply side reel shaft 26. The interlocking plate 68 is located below the tension arm 58. The interlocking plate 68 is rotatably supported by the main chassis 2 via a support shaft 70 positioned between the support shaft 62 and the supply side reel shaft 26 of the tension arm 58. The interlocking plate 68 has a pair of arms, and these arms extend in a substantially V-shape opposite to the tension arm 58. Among these arms, one arm located on the tension arm 58 side becomes the first box 69.

The tension arm 58 and the interlocking plate 68 are interlocked with each other to enable rotational movement. More specifically, the projection 72 protrudes downward from the outer edge on the left side of the tension arm 58. The interlocking plate 68, that is, the engaging mechanism 74 of the first arm 69 is in contact with the protrusion 72 from the inside. The engagement mechanism 74 is formed integrally with the proximal end of the first arm 69.

In the state of FIG. 2, the first arm 69 of the interlocking plate 68 is in a free state, whereby the tension plate 58 is rotated counterclockwise by receiving the elastic support force of the tension coil spring 64. have. According to the rotational movement of the tension plate 58, the tension arm 58, the projection 72 pushes up the engagement mechanism 74 of the first arm 69, and rotates the interlocking plate 68 clockwise. I'm exercising. Therefore, the other end of the second arm 76 of the interlocking plate 68 is positioned near the supply side reel shaft 26. In this state, the tip of the second arm 76 is located near the supply side reel shaft 26. In this state, the tip of the second arm 76 faces the winding side reel shaft 28, and the pin 78 protrudes upward from the tip.

In addition, a cam plate 80 as a movable member is disposed on the main chassis 2. The cam plate 80 is located above the interlocking plate 68. The cam plate 80 has a rectangular shape extending along a line connecting the supply side reel shaft 26 and the winding side reel shaft 28, and is freely supported in the longitudinal direction with respect to the lower surface of the main chassis 2.

The lower surface of the cam plate 8 is formed with a trapezoidal cam 82 cooperating with the pin 78 of the second arm 76 described above. The surface of the trapezoidal cam 82 toward the second arm 76 side is an inclined cam surface.

In FIG. 2, the rack 84 is formed in the right edge of the cam plate 80 by the side edge of the capstan 10 side. The pinion 86 meshed with the rack 84 is rotatably supported by the main chassis 2 freely. In addition, the rack plate 88 meshes with the pinion 86. The rack plate 88 extends the side of the capstan 10 toward the mode switching device 14 described above on the cam plate 80 side as shown in FIG. 5 and moves freely to the main chassis 2. Supported.

The control motor 16 of the mode switching device 14 is disposed on the motor mounting table 90 located above the main chassis 2. The worm 92 is provided on the output shaft of the control motor 16. In addition, the motor mounting stand 90 of FIG. 5 is shown by the dashed-dotted line, and the part of the main chassis 2 is shown by the dashed-dotted line.

The worm 92 of the control motor 16 is engaged with the upper worm gear 96 of the two-stage worm gear 94. The two-stage worm gear 94 has a central portion and a lower end thereof rotatably supported by the motor mounting table 90 and the main chassis 2.

The lower worm gear 98 of the two-stage worm gear 94 meshes with the large-diameter gear 102 of the two-stage gear 100. The two-stage gear 100 is supported by the main chassis 2 in a freely rotating manner with its large-diameter gear 102 upward. The small-diameter gear 104 of the second gear 100 is located at the same level as the rack plate 88 below the main chassis 2 and is engaged with the rack plate 88.

Therefore, when the control motor 16 rotates, the rotation is converted into the reciprocating motion of the rack plate 88 through the two-stage worm gear 94 and the two-stage gear 100. And again this reciprocating motion is converted to the rotation of the pinion 86, and then converted to the reciprocating motion of the cam plate 80. That is, the cam plate 80 may reciprocate by the control motor 16.

In addition, the rotational force of the large-diameter gear 102 in the second gear 100 is transmitted to the disconnection mechanism of the pinch roller 12 with respect to the capstan 10 described above and the tape loading mechanism (not shown) described below. It is used as the power to operate the instruments respectively.

A portion 36 of the tape loading mechanism is directed toward the interlocking plate 68 described above on the large-diameter gear 102 side. At the end portion of the tape loading mechanism extending to the interlocking plate 68 side, an abutting surface cooperating with the pin 71 (see Fig. 2) at the tip of the first arm 69 is formed.

Guide grooves 106 are formed on the upper surface of the cap plate 80. The guide groove 106 extends in the longitudinal direction of the cam plate 80 while being bent in accordance with a predetermined bending pattern.

On the other hand, the control link 108 is disposed above the cam plate 80. The control link 108 is composed of a pair of link arms forming an L shape. The control link 108 is freely supported on each side of the main chassis 2 through the support shaft 109. One of the link arms 110 is connected to the winding side reel shaft 28 along the cam plate 80. Moreover, the pin 111 protrudes downward at the tip of the link arm 11. The lower end of the pin 111 is fitted freely in the guide groove 106 of the cam plate 80.

The link arm 112 on the other side of the control link 108 extends beyond the cam plate in the direction intersecting the longitudinal direction of the cam plate 80. And the gear plate 113 is connected to the front end of the link arm 112 through the pin connector (115). The gear plate 113 is located between the supply side reel shaft 26 and the winding side reel shaft 28 described above, and the center thereof is freely installed on the gear shaft 114. The gear shaft 114 is located on the bisector of the line connecting the supply side reel shaft 26 and the winding side reel shaft 28 and is supported by the main chassis 2.

The gear shaft 114 is provided with a smaller center gear 116 and a larger diameter power transmission pulley 118 than the supply side reel gear 32, respectively. Between these center gear 116 and a power transmission pulley, a friction transmission mechanism for setting a tape winding torque is provided. The center mechanism 116 is located between the gear plate 113 and the main chassis 2 and the power transmission pulley 118 is located on the lower surface side of the main chassis 2. The power transmission pulley 118 is connected to the output pulley 122 having a smaller diameter than the power transmission pulley 118 via the endless driving belt 120.

A reduction mechanism is formed by the outer diameter difference between the supply side reel gear 32, the center gear 116, the power transmission pulley 118, and the output pulley 122.

At the left end of the gear plate 113, the supply side relay gear 126 is provided freely for rotation. At the right end of the gear plate 113, a winding side relay gear 128 is provided freely for rotation. These relay gears 126 and 128 are always engaged with the center gear 116 apart from each other in the radial direction of the center gear 116, and are arranged at the same level as the supply side and the wound side reel gears 32 and 54 described above.

In addition, although the cam plate 80 and the cam groove 106 differ in the shape in FIG. 2 and FIG. 5, this is for convenience at the time of drawing drawing, and these actual shapes are more accurate in the case of FIG. Do. Next, the operation of the above-described video tape recorder will be described.

When the cassette C is inserted into the cassette holder 6, the cassette loading mechanism 4 is positioned at its loading position as indicated by the dashed dashed line in the second middle through the cassette holder 6.

Upon completion of the loading of the cassette C, the control motor 16 of the mode switching device 14 is rotated in one direction. As described above, the cam plate 80 moves to the ready position shown in FIG. 2 through the rack plate 88 and the pinion 86 as the control motor 16 rotates.

On the other hand, the rotation of the control motor 16 is converted to the movement of the tape loading mechanism through the large-diameter gear 102 of the second gear 100 as described above. By the operation of the tape loading mechanism, the tape T of the cassette C is drawn out so as to continue along the traveling path defined by the guide roller 22, the erasing head 18, the audio control head 20, and the like. It is wound around the cylinder 8. In addition, only the loading guide 13 of the tape loading mechanism is shown in FIG.

When the tape loading mechanism is moved, part of the loading mechanism 36 escapes from the pin 71 of the first arm 69 in the interlocking plate 68, and the interlocking plate 68 is made free. Thereby, the tension arm 58 receives the elastic support force of the tension coil spring 64, and rotates it counterclockwise to the rotational movement position shown in FIG. The tension arm 58 imparts a predetermined tension to the tape T drawn out from the cassette C via the pin 66 at its distal end. In addition, as described above, in conjunction with the counterclockwise rotation of the tension arm 58, the interlocking plate 68 rotates clockwise and is retained in the position shown in FIG.

On the other hand, when the tension arm 58 rotates in the counterclockwise direction, the braid band 56 is wound around the reel disk 30 of the supply side reel shaft 26 to be in close contact with the reel disk 30, that is, the supply side reel shaft ( 26) gives a predetermined braking force.

When the cam plate 80 is in the ready position, the control link 108, that is, the pin 111 of the link arm 110, is located at the center position of the guide groove 106 in the cam plate 80, The control link 108 is held in the position shown in FIG. In this case, the link arm 112 of the control link 108 is located on the line connecting the support shaft 109 and the gear shaft 114 of the gear plate 113. As a result, the gear plate 113 is positioned at the neutral position. In this neutral position, the left and right relay gears 126 and 128 of the gear plate 113 are separated from the corresponding reel gears 32 and 54, respectively.

Upon receiving the instruction to switch to the regeneration mode in the state of FIG. 2, the control motor 16 rotates again in one direction. Then, as the tape loading mechanism moves, the pinch roller 12 is moved from the position of the dashed line in the second middle to the position of the solid line, and the tape T of the cassette C between the capstan 10 and the pinch roller 12 is moved. ) Is clamped. The cam plate 80 is then moved leftward from the ready position shown in FIG. 2 to the regeneration mode position shown in FIG. As the cam plate 80 moves, the pin 111 of the control link 108 moves relative to the guide groove 106 of the cam plate 80. Here, the pin 111 of the control link 108 in the regeneration mode position is displaced toward the winding side reel shaft 28 as compared with the case in the ready position. The displacement of the pin 111 causes the control link 108 to rotate clockwise about its support shaft 109.

The clockwise rotation of the control link 108 rotates the gear plate 113 counterclockwise through the pin tie connector 115. As a result, the winding side relay gear 128 of the gear plate 113 meshes with the winding side reel gear 54. In this case, the power transmission path from the capstan motor 124 to the winding side reel gear 54 is connected.

In this state, when the capstan motor 124 is rotated in one direction, the rotation is transmitted to the power transmission pulley 118 to the drive belt 120 and this rotation is transmitted to the center gear 116 through the friction transmission mechanism. The rotation of the center gear 116 is transmitted to the winding side reel gear 54 through the winding side relay gear 128, and rotates the winding side reel shaft to the tape winding side. Therefore, the tape T passing through the head cylinder 8 is wound on the winding side reel shaft 28 side, and the regeneration mode is executed.

During the regeneration mode, the braking force is applied to the supply side reel shaft 26 by the brake band 56, and the tension is applied to the tape T by the tension arm 58. Therefore, the regeneration can be performed satisfactorily without relaxation in the tape T supplied from the cassette C to the head cylinder 8.

The rotation of the capstan motor 124 is stopped upon receiving the instruction to switch to the rewind regeneration mode in the above-described regeneration mode. And the control motor 16 is rotated again in one direction. The rotation of the control motor 16 causes the cam plate 80 to move back to the left as shown in FIG. 7, and the trapezoidal cam 82 moves to the second arm 76 in the interlocking plate 68. The position immediately before the pin 78 is reached. As the cam plate 80 moves, the pin 111 of the control link 108 moves relative to the cam groove 106 of the cam plate 80 again, and the control link 108 has a shape of the cam groove 106. Along the counterclockwise rotation. This rotational movement rotates the gear plate 113 clockwise. As a result, the winding-side relay gear 128 is separated from the reel gear 54, and the supply-side relay gear 126 meshes with the supply-side reel gear 32.

At this time, the power transmission path from the capstan motor 124 to the supply side relay gear 126 is in a connected state. Since the load of the capstan motor 124 which is stopped is applied to the supply side relay gear 126 through the reduction mechanism, free rotation of the supply side relay gear 126 is regulated.

When the feed side relay gear 126 is engaged with the feed side reel gear 32, the gear end of the feed side relay gear 126 draws an arc of the arc of the reel gear 32 by rotating the gear plate 113. Crash at the end. At this time, since the free rotation of the supply-side relay gear 126 is restricted, the reel gear 26 is pushed counterclockwise more in the rewind side, that is, in FIG. At this time, since the braking force by the brake band 56 is given to the supply side reel shaft 26, the supply side reel shaft 26 is stopped. As a result, only the reel gear 32 overcomes the elastic bearing force of the tension coil spring 38 and rotates independently of the supply side reel shaft 26.

When the rotation of the reel gear 32 is seen in FIG. 4, the pin 42 of the reel gear 32 has a circular arc groove on the reel shaft 26 side as much as the range R of the position of the two-dot chain line at the position of the solid line. 50) I move inside.

Thereafter, even if the cam plate 80 is moved further to the left, the control link 108, that is, the gear plate 113 is maintained in its rotational position as can be in the shape of the cam groove 106 of the cam plate 80. . However, as shown in FIG. 8, the second arm 76 of the interlocking plate 68 rotates counterclockwise as its pin 78 rises to the inclined cam surface of the trapezoidal cam 82. As shown in FIG.

In this way, when the linkage arm 76 rotates counterclockwise, the engagement mechanism 74 of the linkage plate 68 presses the projection 72 of the tension arm 58. As a result, the tension arm 58 is returned slightly in the clockwise direction in conjunction with the rotational movement of the second arm 76 and starts to release the tension of the tape T. FIG.

On the other hand, as the tension arm 58 returns, the braking force of the supply side reel shaft 26 by the brake band 56 also rapidly decreases. Here, when the elastic bearing force of the tension coil spring 38 connecting the reel shaft 26 and the reel gear 28 with respect to the braking force is won, the elastic bearing force is received and the reel shaft 26 rotates independently of the reel gear 28. It rotates counterclockwise more than the rewind side, that is, in FIG. In this case, as shown in Fig. 4, the pin 40 on the reel shaft 26 side moves in the direction of the arrow.

Therefore, as the tension arm 58 is returned, the tension arm 58 is rotated from the position shown by the double-dotted dashed line in the eighth degree to the position of the solid line, so that even if the running path of the tape T is shortened, the shortening of the running path is performed. Since the supply side reel shaft 26 rotates to the rewinding side to rewind the tape T, the tape T does not loosen on the outer circumferential surface of the head cylinder 8.

Subsequently, when the capstan motor 124 is reversely rotated and the rewind regeneration mode is executed in the preparation step, the rotational force is transmitted from the supply relay gear 126 to the reel gear 32, and the reel gear 32 is supplied to the supply side reel shaft ( 26) and rotates to the rewind side. At the same time, the capstan 10 also reverses. Therefore, the tape T is returned from the capstan 10 and the pinch roller 12, and the tape T is rewound stably by the rotation of the supply side reel shaft 26 while being in good contact with the outer circumferential surface of the head cylinder 8. As a result, the rewinding reproduction can be performed without causing the image to be disturbed due to the relaxation of the tape T. FIG.

In the above-described embodiment, although the tension coil spring 38 is used as the elastic support means, a twist coil spring may be used instead of the tension coil spring.

As described above, according to the video tape recorder of claim 1, when the tape is released from the playback mode to the rewind playback mode, the tension of the tape is released and the supply side reel shaft is rotated to the rewind side without using a dedicated motor. Do not. Therefore, even when the rewind playback mode is shifted, the tape can be rewound while being in close contact with the head cylinder, and the rewind playback can be stably performed.

According to the video tape recorder of claim 2, the supply side reel gear can be rotated independently with respect to the supply reel shaft while resisting the elastic support means simply by giving the circular motion to the relay gear of the power transmission means. Therefore, while the tension release of the tape and the braking force of the supply side reel shaft are released, the supply side reel shaft is rotated to the rewinding side, and the relaxation of the tape is certainly prevented.

Further, according to the video tape recorder of claim 3, the circular motion of the relay gear is simply realized by the gear plate and the link means which only rotates the gear plate in accordance with the operation mode. According to the video tape recorder of claim 4, the elastic support means can be realized simply by connecting between the supply side reel shaft and the supply side reel gear with a tension coil spring.

Claims (4)

In the preparation means at the time of switching from the tape playback mode to the rewind playback mode, the rotational force of the capstan motor 124 can be transmitted to the supply side reel shaft 26, and then the supply side reel shaft is reversed by reversing the rotation direction of the capstan motor. A video tape recorder which rotates to a rewind side of a tape and switches from said playback mode to a rewind playback mode, wherein Tension means (58, 64) for tensioning the tape directed to the head cylinder (8) during the regeneration mode and releasing the tension in the preparation step; A braking means 56 which gives a predetermined braking force to the supply side reel shaft in the regeneration mode and releases the braking force in association with the release of tension of the tension means in the preparation step; A feed side reel gear 32 and a relay gear 126 rotatable under the rotational force of the capstan motor, the feed side reel shaft 32 being coaxial with the supply side reel shaft and rotatably engaged with a predetermined angle with respect to the reel shaft. A power transmission means (80) for engaging the relay gear in the rotational stopped state with the supply side reel gear before releasing the braking force of the shaft; Elastic support means (38) for rotationally supporting the supply side reel shaft and the supply side reel gear in opposite directions; When the supply side reel gear and the relay gear mesh with each other, the supply gear reel gear receives the braking force of the braking means with respect to the supply side reel shaft which is stopped by the brake gear against the rotational elastic support force of the elastic support means. And an advancing means (108,113) for independently rotating said predetermined amount of rotation on said rewinding side. The method of claim 1, And said advancing means imparts an arc motion to said relay gear and makes it collide with said supply side reel gear when engaging said relay gear with said supply side reel gear. The method of claim 2, The power transmission means includes a movable member 80 that moves from the regeneration mode position to the position of the rewind regeneration mode according to the switching to the rewind regeneration mode, wherein the advance means are freely supported by the rotational movement in the vicinity of the movable member. And a gear plate 113 having the relay gear at one end, and link means 108 for rotating the gear plate in association with the movement when the movable member moves from the regeneration mode position to the rewind regeneration mode position. Video tape recorder, characterized in that. The video tape recorder according to claim 1, wherein said elastic support means includes a tension coil spring (38) connecting between said supply side reel shaft and said supply side reel side gear.