JPH0628118B2 - Video tape recorder's reel drive mode switching mechanism - Google Patents

Description

The present invention relates to a small-sized home video tape recorder,
More particularly, it relates to a mechanism for switching the drive mode of each reel so that the take-up reel is rotated at a constant speed during recording / reproduction and the supply or the take-up reel is rotated at high speed during winding / fast-forwarding.

[Technical background of the invention] In a video tape recorder, there are two modes: a recording / playback mode (hereinafter referred to as a play mode) and a winding / fast-forward mode. Normally, in the play mode, the drive system is provided with a clutch mechanism for winding the tape at a constant speed, and in the winding / fast-forward mode, a mechanism for directly driving the drive system and the reel disk is provided for performing high-speed rotation. There is.

That is, in a conventional video tape recorder, an idler roller that selectively engages two reel disks, a play mode gear, and a take-up / fast-forward mode gear are coaxially provided via a clutch mechanism. , An intermediate rotating body that engages with the idler roller to transmit its rotation, a mode switching gear that selectively engages the play mode gear and the winding / fast-forward mode gear, and the mode switching gear that rotates And a drive source for driving. In the play mode, the mode switching gear moves up and down and meshes with the gear for the play mode to rotate the intermediate rotor and rotate the reel disk on the winding side by the idler. In the winding / fast-forward mode, the mode switching gear winds /
It meshes with the gear for the fast-forward mode and rotates the intermediate rotor to rotate the reel disk on the supply side in the winding mode and the reel disk on the winding side in the fast-forward mode by the idler. When the stop operation is performed from the take-up / fast-forward mode, the brake operates and the reel disc stops instantaneously, but the mode switching gear meshes with the gear for the take-up / fast-forward mode to the gear for the play mode, The drive system is in play mode. Therefore, when the reel drive is in the play mode, even if the capstan motor is stopped, due to inertia of the capstan flywheel and the like, a rotational force is applied to the reel disk on the side where the idler is in contact. Therefore, there is a drawback that an extra load is applied to the tape.

[Object of the Invention] An object of the present invention is to improve the drawbacks of the reel drive mechanism in the conventional video tape recorder as described above, and in the case of stopping the reel disk from a state in which the reel disk is rotated at a high speed with a simple structure, the reel is driven. (EN) Provided is a reel drive mode switching mechanism in a video tape recorder which stops the disk instantaneously and does not apply an excessive load to the tape when stopped.

[Structure of the Invention] A reel drive mode switching mechanism of a video tape recorder according to the present invention will be described with reference to the drawings. By selectively engaging a capstan motor with a supply or take-up reel disk (16, 17). , A first idler member (158) for rotating these reel disks (16, 17) at a constant speed, a capstan motor, and a supply or take-up reel disk (1
6 and 17) to selectively engage these reel discs (1
Second idler member (144) that rotates 6 and 17) at high speed
An elastic member (167) for elastically restricting the first and second idler members (158, 144) so that they are not always supplied or engaged with the take-up reel discs (16, 17); At least one of the first and second idler members (158, 144) is engaged with each part of the second idler member (158, 144) and resists the elastic force of the elastic member (167) when moved in the horizontal direction. A mode slider (39) for releasing one regulation and transmitting the rotation of the capstan motor to at least one of the supply or take-up reel disks (16, 17) and recording, reproduction,
Mode slider (39) interlocking with operations such as winding and fast-forwarding
And a mode slider (39) having means (1) for moving the
Is a cam surface (94, 95, 94) that controls the position of the first idler member (158) at a portion that engages with a part of the first idler member (158).
96) and a first sub-slider (93), and a part of the second idler member (158) supported slidably and movably in conjunction with the first sub-slider (93). A second sub-slider (101) having a cam surface for controlling the position of the second idler member (144) formed at the engaging portion, and driven by the mode slider moving means (1), It is characterized by further comprising a one-way clutch (117) for moving the second sub-slider (101) so as to release the engagement between the second idler member (144) and the supply or take-up reel disk (16, 17). It is a thing.

[Operation] With this configuration, when switching from the stopped state to the play action,
The mode slider (39) is moved by the first idler member (158) so as to rotate the take-up reel disk (17).
When switching to review operation, the mode slider (39)
Is supplied by the first idler member (158) to the reel disk (1
6) Move to rotate. During the fast forward operation, the mode slider (39) moves so that the second idler member (158) contacts the take-up reel disk (17), and during the rewinding operation, the mode slider (39) moves the second idler member (158). The member (158) is moved so as to abut the supply reel disc (16), and the disc is rotated at high speed. If a stop signal is given during the fast-forwarding or rewinding operation, the one-way clutch (117) is driven by the mode slider moving means (1), and the second idler member (144) and the supply or take-up reel disk (16, 17). ) Is disengaged from the second sub-slider (101). As a result, the reel drive fast-forward / rewind mode is instantly released. At this time, since the mode slider (39) is in the fast-forward / rewind position, the reel-driving play mode is still released. Therefore, the reel drive system becomes free,
Even if the high-speed rotating reel discs (16, 17) are stopped instantaneously, the rotation due to the inertia of the capstan wheel is not transmitted to the reel discs (16, 17) and the tape is not overloaded. .

[Embodiment] An embodiment of the present invention shown in the drawings will be described below. The video tape recorder in this embodiment has six mode switches: fast forward / rewind, stop, tape loading, pause, review, and play, and these mode switches are shown in FIGS. This is performed by the cam gear 1 having a cam groove on the lower surface.

First, the drive mechanism of the cam gear 1 will be described. The power support plate 3 is provided on the lower surface of the substrate 2, and the DC motor 4 is attached to the power support plate 3. A first pulley 6 is attached to a drive shaft 5 of the motor 4, and a first endless belt 7 is attached to the first pulley 6.
Is hung. The first endless belt 7 is also wound around a second pulley 8 having a larger diameter than the first pulley 6, and the second pulley 8 is attached to a rotary shaft 9 rotatably supported by the power support plate 3. Has been. Rotating shaft 9
In addition, the third pulley 11 having a smaller diameter than the second pulley 8
Is installed. This third pulley 11 and power support plate 3
Mounted on a worm shaft 12 rotatably supported on
A second endless belt 14 is wound around a fourth pulley 13 having a diameter larger than that of the pulley 11. A worm gear 15 is attached to the worm shaft 12, and the worm gear 15 meshes with a gear 87 provided on the outer circumference of the cam gear 1. The cam gear 1 is rotatably supported by the shaft 88 of the force support plate 3.

Therefore, the rotation of the motor 4 is changed from the first pulley 6 to the first pulley 6.
It is transmitted to the second pulley 8 via the endless belt 7, and the rotation shaft 9 is decelerated and rotated. This decelerated rotation further decelerates the fourth pulley 13 via the third pulley 11 and the second endless belt 14. The worm shaft 12 is rotated by the rotation of the fourth pulley 13, and the cam gear 1 is also rotated by this rotation. The rotation of the cam gear 1 controls various operation modes described below.

First, tape loading will be described. The tape loading mechanism is provided on the back surface of the cam gear 1 as shown in FIG. 4, and is controlled by a back cam groove 21 extending from the central portion toward the outer peripheral portion. The back cam groove 21 has a first portion 21p to q extending concentrically from the center thereof, a second portion 21q to r gradually expanding from the first portion 21q toward the outer periphery, and a second portion 21q to r. Third portion 21r-s extending so as to gradually expand from the portion 21r toward the outer periphery
And a fourth portion 21s to t extending from the third portion 21s so as to gradually spread in the outer peripheral direction, and a fifth portion 21t to u extending concentrically from the fourth portion 21t. It is continuously and spirally formed.

The upper end of the lower guide pin 22 is loosely fitted in the back cam groove 21 of the cam gear 1. The lower end of the guide pin 22 is fixed to the toothless gear plate 23. Missing tooth gear plate 23
Has a rear end rotatably attached to the power support plate 3 by a support pin 24. Rack teeth 25 are provided on the tip peripheral surface of the toothless gear plate 23. This rack tooth 25
It meshes with the first loading gear 26 and meshes with the first loading gear 26 or the second loading gear 27. The first and second loading gears 26 and 27 are provided on the substrate 2 as shown in FIG. 1, and are rotatably attached to the lower surface of a loading plate 28 to which a rotary head (not shown) and the like are attached. . The loading plate 28 is provided with two guide grooves 29 so as to surround the rotary head, and a pole base 31 is attached to each groove 29 so as to be movable along the grooves 29. A loading post 10 for pulling out the tape is provided upright on the pole base 31. An arm mechanism (not shown) linked to the first and second loading gears 26 and 27 interlocks with the rotation of the loading gears 26 and 27 on the pole base 31 to pull out the tape from the tape cassette and rotate the head. It is for winding the outer periphery of about 190 degrees. Since the conventional mechanism can be used for the arm mechanism,
The detailed description and drawings are omitted.

As described above, the first portion 21 of the back cam groove 21 of the cam gear 1
Since p to q are formed concentrically, even when the cam gear 1 starts to rotate, the upper guide pin 22 keeps the first portion 21p.
The tooth-chipped gear plate 23 cannot pivot while it is positioned at ~ q. The cam gear 1 rotates further and the upper guide pin 22
Are positioned on the second portions 21q to 21r, the upper guide pin 22 is moved in the outer peripheral direction, whereby the toothless gear plate 23 rotates about the support pin 24 as a fulcrum, and the first and second loading gears are rotated. 26 and 27 also rotate. As a result, the pole base 31 advances along the guide groove 29. To move the pole base 31 forward, the upper guide pin 22 moves the second portion 21q to
r, the third portion 21r-s and the fourth portion 21s-v while being located. When the guide pin 22 reaches the fourth portion 21v, the pole base 31 hits a stopper (not shown),
After that, when the guide pin 22 is positioned at the fourth portion 21t, the pole base 31 is locked to the stopper by the action of the coil spring in the loading gear, and is accurately positioned. Since the fifth portions 21t to u are concentrically formed like the first portions 21p to q, the upper guide pin 22 does not move in the outer peripheral direction, and even if the cam gear 1 rotates, the toothless gear plate. 23 does not pivot.

Transmission to other mechanical elements is carried out by a front cam groove 32 extending spirally from the central portion toward the outer peripheral portion on the surface of the cam gear 1 as shown in FIG. The front cam groove 32 extends concentrically from the center of the front cam groove 32, and has a first portion 32a-b for fast-forwarding / rewinding and a second portion 32b-that gradually extends from the first portion 32b in the outer peripheral direction. c and a third part 32c-d for stopping which extends concentrically from this second part 32c
And fourth portions 32d to e extending from the third portion 32d so as to gradually spread in the outer peripheral direction, and the fourth portion 32e.
Fifth portions 32e-f extending concentrically from the
A sixth portion 32f extending linearly outward from the portion 32f
g, a seventh portion 32g to h for concentrically extending from the sixth portion 32g, and an eighth portion 32h extending from the seventh portion 32h so as to gradually spread in the outer peripheral direction.
~ I, a ninth portion 32i-j for review concentrically extending from the eighth portion 32i, and the ninth portion 32i
The first extending from j to be gradually expanded in the outer circumferential direction
The 0th portion 32j to k and a tenth portion 32k to l extending concentrically from the tenth portion 32k are continuously and spirally formed.

The lower end of the upper guide pin 33 is loosely fitted in the front cam groove 32 of the cam gear 1. The upper end of the upper guide pin 33 is located above the cam gear 1 and protrudes onto the substrate 2 through a guide groove 34 provided in the substrate 2 so as to extend from the central portion of the cam gear 1 to the outer peripheral portion. ing. Upper guide pin
The upper end of 33 is pressed into one end of the mode lever 35.
The middle portion of the mode lever 35 is rotatable about a pivot pin 36 fixed to the substrate 2 as a fulcrum. A long hole 37 is formed at the other end of the mode lever 35, and a pin 38 is loosely fitted in the long hole 37. The pin 38 is erected on one end of a mode slider 39 extending in the front direction on the substrate 2.

The mode slider 39 has two guide holes 20 extending in the longitudinal direction at both ends thereof, and a pin 30 standing on the board 2 is fitted into the guide holes 20 so that the board 2 can slide freely. Supported above. FIG. 1 shows a stopped state, and the lower end of the upper guide pin 33 is located in the third portion 32c to 32d of the front cam groove 32. From this state, the cam gear 1 rotates clockwise, and the upper guide pin 33 moves from the third portion 32c-d to the second portion 32b-c, and along with this, the upper guide pin 33 moves in the inner circumferential direction. Will move. As a result, the mode lever 35 rotates clockwise, and the mode slider 39 interlocked with this moves to the left to enter the fast-forward / rewind mode.

On the other hand, when the cam gear 1 rotates counterclockwise from the stopped state, the upper guide pin 33 moves from the third portion 32c to d to the fourth portion.
32d-e, the upper guide pin 33 moves in the outer peripheral direction. As a result, the mode lever 35 rotates counterclockwise and the mode slider 39 moves to the right to enter the recording / reproducing mode (hereinafter referred to as the play mode).

Next, the case of the play mode will be described. When the cam gear 1 rotates from the stopped state in FIG. 1 and the back side cam groove 21 advances the pole base 31 to complete the tape loading, the upper guide pin 33 The lower end is located in the sixth portion 32f to 32g of the front cam groove 32, from which the eleventh portion 32f
Move to kl. Along with this movement, the mode lever
35 rotates clockwise around the pivot pin 36 as a fulcrum to move the mode slider 39 to the right in FIG. The upper end of the upper guide pin 33 protruding above the mode lever 35 is engaged with the upper side edge of the tension arm 42 in FIG. 1, and one end of the tension arm 42 is located near the pivot pin 36. It is rotatably supported on the substrate 2 by 43. A support lever 18 is also pivotally attached to the tension arm 42, and one end of a tension band 19 is attached to the support lever 18. The other end of the tension band 19 is wound around the outer circumference of the supply reel disc 16 and then fixed to the substrate 2. One end of the coil spring 44 is attached to one end of the tension arm 42, and a tape guide post 45 is provided upright at the other end. The other end of the coil spring 44 is attached to the substrate 2 so that the tension arm 42 gives a turning force counterclockwise with the pin 43 as a fulcrum. Therefore,
By the counterclockwise rotation of the mode lever 35, the tension arm 42 first rotates until the upper guide pin 33 comes into contact with the notch 40 formed in the upper side edge of the tension arm 42. After that, it follows the movement of the upper guide pin 33 and rotates counterclockwise. By rotating the mode lever 35 counterclockwise, the tension band 19 is supplied to the supply reel disc 16
The tape guide post 45 is wound around the outer periphery of the tape to obtain a predetermined back tension, and the tape guide post 45 is located at a predetermined position during play to apply a predetermined tension to the tape.

On the other hand, when the mode slider 39 moves to the right, the pin 46 erected on the upper surface of the right end of the mode slider 39 also moves to the left. The pin 46 is loosely fitted into a long hole 49 provided at one end of a first pinch roller lever 48 whose substantially middle portion is rotatably supported by a pin 47. At an intermediate portion of the first pinch roller lever 48, one ends of two superposed link plates 51 (only the upper link plate is shown in FIG. 1) are rotatably attached. Two link plates
Each of the 51 has an elongated hole 52 therein, and a pressing spring 53 is inserted into the elongated hole 52. Upper link board
One end of 51 is rotatably supported by the pin 54 with respect to the first pinch roller lever 48, and a slot 55 is formed at the other end. A pin 57, which is erected on the lower surface of one end of the second pinch roller lever 56, is loosely fitted in the elongated hole 55. pin
The lower end of 57 is rotatably attached to the other end of the lower link plate 51. An elongated hole (not shown) similar to the elongated hole 55 of the upper ring plate 51 is formed at one end of the lower link plate 51, and the pin 54 is loosely fitted into this elongated hole.

The second pinch roller lever 56 has a pivot pin 58 fixed to a substantially middle portion, and is rotatably attached to a bearing (not shown) attached to the substrate 2. The second pinch roller lever 56 rotates about the pivot pin 58. A pinch roller 59 is rotatably supported at the other end of the second pinch roller lever 56. Therefore, the pinch roller 59 is constantly elastically pressed toward the capstan shaft 61 by the pressing spring 53 in the link plate 51, and the mode slider 39
1st pinch roller lever 48
Rotates counterclockwise and pushes the ring plate 51 upwards,
As a result, the second pinch roller 56 also rotates counterclockwise and presses the pinch roller 59 against the capstan shaft 61.

Next, the brake mechanism for the supply reel disc 16 and the take-up reel disc 17 will be described with reference to FIG. The supply reel disc 16 is provided with a main brake arm 62 and a sub brake arm 63. The main brake arm 62 is
Although not shown at one end, a friction material having a high friction coefficient such as rubber or synthetic resin is attached, and the friction material presses against the outer peripheral surface of the reel disk 16 to stop rotation, and the brake bar 64 and the brake bar.
One end of the connecting bar 65 is located at a substantially intermediate portion of the 64, and the extending direction of the connecting bar 65 is orthogonal to the extending direction of the brake bar 64. At the intersection of the brake bar 64 and the connecting bar 65, the lower end is pivotally attached to a pivot pin 67 fixed to the brake support plate 66. An engagement pin 68 is also provided upright on the brake bar 64. Sub brake arm 63
Although not shown in the figure, a friction material such as felt is attached to one end of the reel disk.
It stops rotation by pressing against the outer peripheral surface of 16.
It is almost U-shaped. The other end of the sub brake arm 63 is pivotally attached to a pivot pin 69 whose lower end is fixed to the brake support plate 66. An engagement pin 71 is provided upright in the vicinity of the pivot pin 69, and one end of a coil spring 72 is attached. The other end of the coil spring 72 is
It is attached to a locking hook 73 fixed to the brake support plate 66, and the coil spring 72 causes the friction material to come into pressure contact with the outer peripheral surface of the reel disc 16 so that the auxiliary brake arm is provided.
63 is pulled elastically.

The brake mechanism of the take-up reel disc 17 is also composed of a main brake arm 74 and a sub-brake arm 75, similarly to the supply reel disc 16 side. Although not shown, the main brake arm 74 is provided with a friction material made of rubber or synthetic resin having a high friction coefficient, and a brake bar 76 that stops rotation by contacting the friction material with the outer peripheral surface of the reel disc 17 with pressure. , One end of which is located approximately in the middle of the brake bar 76, and the extending direction thereof is the brake bar 76.
Is integrally formed with the connecting bar 77 orthogonal to the extending direction of the. At the intersection of the brake bar 76 and the connecting bar 77,
A pivot pin 78, the lower end of which is fixed to the brake support plate 66, is pivotally attached. An engagement pin 79 is also provided upright on the brake bar 76. The sub brake arm 75, like the sub brake arm 63 on the supply reel disc 16 side,
Although not shown, a friction material such as felt is attached to one end and has a substantially L shape. The other end of the sub brake arm 75 is pivotally attached to a pivot pin 81 whose lower end is fixed to the brake support plate 66. An engaging pin 82 is provided upright at a corner of the sub brake arm 75, and one end of a coil spring 83 is attached to one end side. The other end of the coil spring 83 is attached to a locking hook 80 fixed to the brake support plate 66, and the coil spring 83 elastically moves the auxiliary brake arm 75 so that the friction material comes into pressure contact with the outer peripheral surface of the reel disc 17. Pulled to.
On the upper surface of the other end of the connecting bar 77, a pair of locking posts 84 and 85, which are spaced apart from each other, are formed.
The other end of the connecting bar 65 on the supply reel disk 16 side is loosely held between 84 and 85. A coil spring 86 is mounted between the other ends of the brake bars 64 and 76, which are opposed to the one ends to which the friction materials are mounted, and the coil springs 86 keep one end of the friction material side on each reel disk 16 at all times. , 17 are elastically pressed against the outer peripheral surface.

The engagement pins 68, 71, 79 project upward from the cutout portion 91 of the substrate 2, and the engagement pin 82 projects upward from the hole 92 of the substrate 2. The upper ends of these engaging pins 68, 71, 79, 82 are
As shown in FIG. 1, a mode slider 39 and a first sub-slider slidably mounted on the mode slider 39.
It is adapted to engage with the side edge of 93 and change its position. That is, on the side edge of the mode slider 39, the first notch 94 for the engagement pin 68, the second notch 95 for the engagement pin 71, and the third notch 96 for the engagement pin 82. And are formed. The first cutout portion 94 is located so as to face the engagement pin 68 when the mode slider 39 is in the stop mode as shown in FIG. 1, and in the other modes, this first cutout portion 94 is provided. It is formed to deviate from 94. Second
The cutout portion 95 is located so as to face the engagement pin 71 when the mode slider 39 is in the stop, tape loading, pause, and review modes, and in the other modes, this second cutout portion is formed. It is formed to deviate from 95. Similar to the second cutout portion 95, the third cutout portion 96 is located so as to face the engagement pin 82 when the mode slider 39 is in the stop, tape loading, pause, and review modes, and otherwise. In the mode (3), it is formed so as to be separated from the third cutout portion 96.

The upper end of the engagement pin 79 engages with the side edge of the first sub-slider 93 slidably mounted on the mode slider 39 to change its position. The first sub-slider 93 includes a guide protrusion 97 formed to protrude downward at a substantially central portion of a side edge facing the side edge on the engagement pin 79 side, and a mode lever.
The engaging pin 98 is provided on the side portion side facing the 35 side so as to project downward. The guide protrusion 97 is provided on the mode slider 39, and is loosely fitted in a long hole 99 extending in the moving direction of the mode slider 39.
Although not shown in the figure, the mode slider 39 is loosely fitted in the elongated hole extending in the same manner as the elongated hole 99, though not shown. First sub slider
A second sub-slider 101 having both ends formed in a substantially hook shape is attached to the lower surface of the end of 93 on the mode lever 35 side. One hook-shaped end portion 102 of the second sub-slider 101 is exposed from the end portion of the first sub-slider 93, and the other hook-shaped end portion thereof.
Reference numeral 103 projects from the side edge of the first sub-slider 93 as shown in FIG. The corner of the other hook-shaped end 103 is a pivot pin 1
It is rotatably supported by the first sub-slider 93 by 06. One end of a coil spring 104 is attached to the other hook-shaped end portion 103, and the coil spring 104 is
Also, the second sub-slider 93, 101 is always elastically biased toward the first pinch roller lever 48. A fourth cutout 105 for the engagement pin 79 is provided in the first sub-slider 93, and like the first cutout 94, the engagement pin 82 when the mode slider 39 is in the stop mode. It is located so as to face with, and in other modes, this 4th
It is formed so as to be separated from the cutout portion 105.

The operation of these brake mechanisms will be described. When stopped, as shown in FIG. 1, the engaging pins 68, 71, 79, 82 respectively have first, second, third and fourth notches 94, 95, 96. ,Ten
It is relative to 5. Since one end of each of the main brake arms 62 and 74 is elastically pulled by the coil spring 104, the brake lever 64 of the main brake arm 62 has a pivot pin.
Counterclockwise with 67 as a fulcrum, and brake bar 76 of main brake arm 74 rotates clockwise with a pivot pin 78 as a fulcrum. By this rotation, the friction material on the other ends of the brake bars 64, 76 is supplied and wound on the reel disc 16,
It contacts the outer peripheral surface of 17, and the main brake is turned on. on the other hand,
In the auxiliary brake arms 63 and 75, the coil springs 72 and 83 rotate counterclockwise about the pivot pins 69 and 81, respectively, so that the felt material contacts the outer peripheral surfaces of the supply and take-up reel disks 16 and 17. The second brake is turned on.

When the motor 4 is driven and the cam gear 1 is rotated in order to shift to the tape loading operation from the stop time, the upper guide pin 33 causes the upper guide pin 33 to move from the third portion 32c to the fourth portion 32 of the front cam groove 32.
It will move to d ~ e. As a result, the mode lever 35 rotates counterclockwise, and the mode slider 39 moves to the right in FIG. The pivot pin 68 rides on the side edge of the mode slider 39 from the left side of the first cutout portion 94, and rotates the brake bar 64 clockwise against the elastic force of the coil spring 86. As a result, the friction material at the other end of the brake bar 64 separates from the outer peripheral surface of the supply reel disc 16 and the main brake is turned off. Meanwhile, the brake bar 64
The rotation of the brake bar is transmitted from the connecting bar 65 to the connecting bar 77 of the main brake arm 74 via the locking posts 84, 85.
Rotate 76 counterclockwise. As a result, the main brake on the take-up reel disc 17 side is also turned off. On the sub-brake side, the engagement pins 71 and 82 still have the second and third notches.
Since it is opposite to 95 and 96, it is in the ON state. The cam gear 1 continues to rotate until the pole base 31 reaches a predetermined position for tape loading, but the fifth position of the front cam groove 32
Since the portions 32e to 32f are formed concentrically, the upper guide pin 33 does not move.

When the cam gear 1 further rotates to move from the tape loading operation to the playing operation, the upper guide pin 33 moves from the sixth portion 32f to g of the front cam groove 32 to the final first portion 32k.
The mode lever 35 further rotates in the counterclockwise direction. Therefore, the mode slider 39 moves further to the right in FIG. 1, and the pivot pin 71 of the auxiliary brake arm 63 on the supply reel disc 16 side rides on the side edge of the mode slider 39 from the left side of the second cutout portion 95. The auxiliary brake arm 63 is rotated clockwise against the elastic force of the coil spring 72. Similarly, the pivot pin 82 of the auxiliary brake arm 75 on the take-up reel disc 17 side is also the third pin.
The sub-brake arm 75 is rotated counterclockwise against the elastic force of the coil spring 83 by riding on the side end of the mode slider 39 from the left side of the cutout portion 96. As a result, the felt material at the other end of each of the auxiliary brake arms 63 and 75 is separated from the outer peripheral surfaces of the supply and take-up reel disks 16 and 17, and the auxiliary brake is also turned off.

When the motor 4 is rotated in the reverse direction to shift from the play operation to the review and pause operation, the cam gear 1 also rotates in the reverse direction,
The mode lever 35 rotates clockwise, and the mode slider 39
Moves to the left. As a result, the engagement pins 71, 82
And the side edge of the mode slider 39 are released, the engaging pins 71 and 82 face the second and third cutout portions 95 and 96, and the auxiliary brake arms 63 and 75 rotate counterclockwise, respectively. Then, the felt material at each of the other ends is pressed against the outer peripheral surfaces of the supply and take-up reel disks 16 and 17 by the elastic force of the coil springs 72 and 83, and only the sub brake is turned off.

When shifting from the stop operation to the fast-forward / rewind operation, the motor 4 is reversely rotated and the cam gear 1 is also reversely rotated. As a result, the upper guide pin 33 moves from the third portion 32c-d of the front cam groove 32 to the first portion 32a-b. Therefore, the mode lever 35 rotates clockwise, and the mode slider 39 moves further leftward from the state shown in FIG. As a result, the engaging pin 79 of the main brake arm 74 on the take-up reel disc 17 side rides up from the right side of the fourth cutout portion 105 of the first sub-slider 93 to the side edge of the first sub-slider 93, and the coil spring 86. The main brake arm 74 is rotated counterclockwise against the elastic force of. As a result, the friction material of the brake bar 76 separates from the outer peripheral surface of the take-up reel disc 17, and the main brake is turned off. The rotation of the main brake arm 74 is transmitted from the connecting bar 77 to the connecting bar 65 of the main brake arm 64 on the supply reel disc 16 side via the locking posts 84 and 85, and the connecting bar 65 rotates clockwise. . As a result, the main brake on the supply reel disc 16 side is also turned off. On the other hand, the engagement pins 71 and 79 are the second pins of the mode slider 39.
E and the mode slider from the right side of the third notch 95, 96
The auxiliary brake arms 63 and 75 rotate clockwise against the elastic force of the coil springs 72 and 83, respectively, and the felt material is supplied to and wound on the reel disc 1.
The auxiliary brake is turned off as it moves away from the outer peripheral surface of 6 and 17.

At the time of shifting from the fast forward / rewind operation to the play operation, the supply and take-up reel disks 16 and 17 are rotating at high speed, and it is necessary to stop them instantaneously. Therefore, this embodiment has a mechanism as shown in detail in FIGS. 6 and 7. The hook member 102 on one side of the second sub-slider 101 is provided with a protruding member 111 protruding downward. A notch protrusion 112 is provided at the other end of the hook-shaped end 102 facing the protrusion member 111. This cutout protrusion 1
When stopped, 12 engages with an engaging piece 113 that protrudes upward at the side edge of the mode slider 39 that faces the cutout side. The engagement piece 113 also functions as a stopper for the rotation of the second sub slider 101 by the coil spring 104.
A pair of clutch pulleys 114, 115 and the clutch pulleys 114, 115 are provided on the rotating shaft 9 of the second and third pulleys 8, 11.
A one-way clutch 117 having a coil spring 116 fitted coaxially between them is attached. The clutch pulley 115 is provided with an engaging piece 118 protruding outward. With the coil spring 116, the one-way clutch 117 rotates the clutch pulley 114 in the same direction when the rotary shaft 9 rotates counterclockwise in FIG. 7, but when it rotates clockwise as indicated by the arrow, Clutch pulley 11
5 is designed to idle, and such a one-way clutch 117 is widely used in various fields.

With this one-way clutch 117, the mode slider 39
Even if the first sub-slider 93 moves leftward with the leftward movement of the first sub-slider, and the projection member 111 of the second sub-slider 101 engages with the engaging piece 118 of the clutch pulley 115, the clutch pulley 115 The rotation shaft 9 continues to rotate.

When shifting from the fast forward / rewind operation to the stop position, the motor 4 rotates in the reverse direction and the rotary shaft 9 rotates in the clockwise direction. As a result, the one-way clutch 117 is also reversed, and the engaging piece 118 of the clutch pulley 115 is pushed up above the projecting member 111 of the second sub-slider 101 as shown by the arrow in FIG. In FIG. 7, the projecting member 111 moves in the direction of the arrow. As described above, since the second sub-slider 101 is rotatably attached to the first sub-slider 93 by the pivot pin 106,
Rotate clockwise about the pivot pin 106. As a result, the engagement between the notch protrusion 112 and the engagement piece 113 is released, and the coil spring 104 causes the second sub-slider 101 to instantaneously move to the right. The rightward movement of the second sub-slider 101 is stopped by the guide protrusion 97 engaging with the edge of a long hole (not shown) provided in the substrate 2. At this time, the engagement pin 79 is instantly separated from the right end of the fourth cutout portion 105, the main brake on the take-up reel disc 17 side is turned on, and the main brake on the supply reel disc 16 side is also turned on to rotate at high speed. The two reel disks 16 and 17 that are running stop instantly.

Next, the review operation will be explained.
The support pins 122 are rotatably supported on the substrate 2 by the support pins 122. An engagement pin 123 is planted on the lower surface of one end of the review bar 121, and the engagement pin 123 is positioned so as to engage with the tip of the first pinch roller lever 48 when the first pinch roller lever 48 is rotated counterclockwise. is doing. Review bar
The spring 124 always elastically shifts counterclockwise by a spring 124, and elastically shifts a review post 125, which is planted on the upper surface of the other end facing the engaging pin 123, toward the capstan 61. . Therefore, as the mode slider 39 moves to the right, the elastic force of the spring 124 is resisted by the counterclockwise rotation of the first pinch roller lever 48 in the tape loading, pausing, reviewing, and playing operations. It rotates clockwise and operates.

Next, regarding the reel drive mechanism, the fifth, eighth, ninth and tenth
It will be described with reference to the drawings. Reel driving teeth 131, 132 are provided on the outer circumferences of the supply reel disc 16 and the reel disc 17, respectively. The teeth 131 are fast-moving / fast-moving attached to a support shaft 133 planted in the brake support plate 66. It is meshed with the outer peripheral teeth 135 of the rewinding disk 134. On the fast forward / rewind disc 134, the outer peripheral teeth 13 are placed through the clutch 136.
A gear 137 for reverse reproduction and review, which has a diameter smaller than 5, is provided coaxially. The teeth 132 are meshed with outer peripheral teeth 141 of a fast-forward / rewind disk 139 rotatably mounted on a support shaft 138 which is parallel to and spaced from the support shaft 133 and is embedded in the brake support plate 66. Fast forward / rewind disc 13
The outer peripheral teeth 135, 141 of 4, 139 are arranged so as not to mesh with each other. Similarly, a play gear 143 having a diameter smaller than that of the outer peripheral teeth 141 is coaxially provided on the fast-forward / rewind disk 138 via a clutch 142. As shown in FIGS. 8 and 10, two fast-forward / rewind disks 134,138.
An idler roller 144 made of a material having a high friction coefficient such as rubber is located between them. The idler roller 144 is rotatably attached to a support shaft 140 provided upright in the center of a substantially cross-shaped idler support plate 145. Support shaft 146
Protrudes downward from an elongated hole 130 formed in the brake support plate 66, and is elastically displaced upward in FIG. 10 by a coil spring (not shown). An engagement pin 146 is integrally provided at an end of the idler support plate 145 on the mode slider 39 side so as to project upward.
The engaging pin 146 is engaged with one end of a fast-forward / rewind lever 147 which is formed in a substantially inverted shape. Fast forward /
The other end of the rewind lever 147 is pivotally attached to a support shaft 148 provided upright on the brake support plate 66, and one end of the fast forward / rewind lever 147 is attached to a coil (not shown) by a spring 149. The spring is pressed against the mode slider 39 against the elastic force of the spring. Locking pin 150 is provided in the middle of the fast forward / rewind lever 147.
Is erected. The locking pin 150 is engageable with the inclined side 152 formed at the boundary between the fifth cutout portion 151 and the fourth cutout portion 105 provided at the substantially center of the first sub slider 93. .

The idler roller 144 also includes a gear disc 1 mounted on a support shaft 153 that is rotatably erected on the brake support plate 66.
A gear portion 155 having a diameter smaller than that of the gear disc 154 is integrally formed on the upper portion of the gear disc 154 so as to be selectively engageable with the outer periphery of the lower portion of the gear disc 54. Brake support plate 6
A pulley 156 is attached to the lower end of a support shaft 153 extending below 6 via a gear mechanism (not shown), and this pulley 156 is connected to a capstan motor (not shown) for tape drive. The endless belt 157 that has been cut is hung. Reverse reproduction with gear 155, review gear 137, pre-
An idler gear 158 is provided so as to selectively mesh with one of the gears 141. This idler gear 158
As shown in FIG. 9, is attached to a pivot plate 159 by a support shaft 161 so as to be rotatable. One end of the pivot shaft 159 is pivotally attached by a pin 163 which is provided upright on the lower surface of an idler gear support plate 162 provided so as to cover the idler roller 144. A sliding plate 164 is slidably interposed between the lower surface of the idler gear support plate 162 and the upper surface of the pivot plate 159. This sliding plate 164 has a notch 1 at its center.
65 (FIG. 5) is formed, and the pin 161 projects into this notch 165. An engaging pin 166 projecting downward is integrally provided at an end of the sliding plate 164 on the mode slider 39 side, and one end of a coil spring 167 is attached. The other end of the coil spring 167 is attached to the idler gear support plate 162, and the sliding plate 164 is constantly pulled toward the mode slider 39. A long hole 169 provided at one end of a pivot lever 168 is loosely fitted in the engagement pin 166.
An intermediate portion of the pivot lever 168 is pivotally attached to the idler gear support plate 162 by a pin 171. Pivoting lever 167
An engaging pin 172 extends downward on the lower surface of the end portion on the mode slider 39 side. The engagement pin 172 is a sixth cutout portion 17 provided at the side edge of the mode slider 39 at the substantially central portion thereof.
It is relative to 3. Therefore, when the engaging pin 172 is pushed upward in FIG. 9, the pivot lever 168 pivots about the pin 171 as a fulcrum, and pushes up the sliding plate 164 against the elastic force of the coil spring 167. Engagement pin of notch 165 of sliding plate 164
The side facing 166 is inclined toward the center, and the apex holds the pin 161 in the center.
Reference numeral 174 in FIG. 5 is a guide protrusion for guiding the sliding of the sliding plate 164.

The operation of the reel drive mechanism described above will be described. When the stopped state shown in the drawing is switched to the play operation, the mode slider 39 moves to the right and pushes the ride-on engagement pin 172 from the left end of the sixth cutout portion 173 to the side edge of the mode slider 39. As a result, the sliding plate 164 is also pushed up, the pivot plate 159 can freely pivot, and the idler gear 158 also becomes free. The idler gear 158 of the pivot plate 159 is a gear disc.
Since the pulley 156 meshes with the gear portion 155 of 154 and rotates clockwise in FIG. 5 during play, the idler gear 158 causes the play gear 143 of the fast forward / rewind disc 139 to rotate.
And fast-forward / rewind disk 139 is rotated. Since the outer peripheral teeth 141 of the fast-forward / rewind disk 139 mesh with the teeth 132 of the take-up reel disk 17, this rotation is transmitted to the take-up reel disk 17.

During the review operation, the pulley 156 rotates counterclockwise in FIG. 5, so that the idler gear 158 reversely reproduces the fast-forward / rewind disc 134, meshes with the review gear 137, and rotates the fast-forward / rewind disc 134. Let Since the outer peripheral teeth 135 of the fast forward / rewind disk 134 mesh with the teeth 131 of the take-up reel disk 16, this rotation is transmitted to the take-up reel disk 16 and causes the tape to run in the opposite direction.

During these two operations, the fast-forward / rewind lever 147 is rotated counterclockwise by the spring 149 because the locking pin 150 of the fast-forward / rewind lever 147 is located away from the inclined side 152 of the first sub-slider 93, and the idler plate 145 is rotated. To the mode slider 39 side. As a result, the idler roller 144 is located at the neutral position and does not engage with the fast-forward / rewind discs 134, 139 or the gear disc 154.

In the case of fast-forward operation, the mode slider 39 moves to the left, and the engagement pin 172 causes the sixth cutout portion 173 of the mode slider 39.
The drive lever 168 is rotated by the coil spring 167, and the sliding plate 164 moves toward the mode slider 39.
As a result, the idler gear 158 is reversely reproduced and the review gear 1
37, the play gear 141 or the gear portion 155 is located at a neutral position where it does not mesh. As the mode slider 39 moves to the left, the first sub-slider 93 moves to the left,
The locking pin 150 of the fast forward / rewind lever 147 rides up from the inclined side 152 of the first sub slider 93 to the side edge. Therefore,
The fast forward / rewind lever 147 rotates clockwise against the elastic force of the spring 149, and the engagement between the tip of the fast forward / rewind lever 147 and the pin 146 of the idler plate 145 is released. This allows the idler plate 145
Is in a free state, and the idler roller 144 contacts the peripheral edge of the gear disk 154 by a spring (not shown). When the pulley 156 rotates clockwise in this state, the idler roller 144 causes the fast-forward / rewind disc 1 to rotate.
It abuts 39 and rotates this disk 139. Disc 1
The rotation of 39 is transmitted to the floor plan disk 17 through the outer peripheral teeth 141, and the tape is wound at a higher speed than during play.

In the case of the rewinding operation, the pulley 156 rotates counterclockwise in the same arrangement as the above-described fast-forwarding operation. As a result, the idler plate 145 is tilted toward the fast-forward / rewind disc 134 via the idler roller 144, and the idler roller 144 abuts on the fast-forward / rewind disc 134 to rotate the disc 134. The rotation of the disk 134 is transmitted to the supply reel disk 16 via the outer peripheral teeth 135, and the tape is rewound at high speed.

When the fast forward / rewind operation is stopped, the one-way clutch 117 causes the notch projection 112 of the second sub-slider 101 and the engaging piece 11 of the first sub-slider 93 as described above.
The engagement with 3 is released, and the coil spring 104 causes the second sub-slider 101 to instantaneously move to the right. Therefore, the support shaft 150 separates from the side edge of the first sub-slider 93 and rotates counterclockwise by the elastic force of the spring 149 to move the idler support plate 145 toward the mode slider 39. As a result, the engagement between the idler 144 and the gear disc 154 is released, and the reel drive fast-forward / rewind mode is instantly released. At this time, since the mode slider 39 is in the fast-forward / rewind position, the reel-driving play mode also remains released. Therefore, the reel drive system is in a free state, and even if the reel disks 16 and 17 that rotate at high speed are stopped instantaneously, the rotation due to inertia of the capstan wheel is not transmitted to the reel disks 16 and 17, and the tape is redundant. It does not impose a heavy load.

The operating states of the main components in the various operations described above are summarized together with the movement of the cam gear 1 as shown in FIG. In the reel drive in the main brake arm 62 and the fast-forward / rewind mode, the portion indicated by the dotted line shows the instantaneous operation by the operation of the second sub-slider 101 described above.

[Advantages of the Invention] As described above, the reel drive mode switching mechanism of the video tape recorder of the present invention selectively engages the rotation drive source and the supply or take-up reel disk to drive these reels at a constant speed. A first idler member that rotates and a second idler member that selectively engages the rotational drive source and the supply or take-up reel disk to rotate these reels at high speed are provided, and the first and the first idler members are provided. Two
The idler member is elastically regulated by an elastic member so as not to be engaged with either the constant supply or the take-up reel disk. Further, each part of the first and second idler members engages with a sliding member movably supported in the horizontal direction, and the position of this sliding member resists the elastic force of the elastic member to cause the first The regulation of either or both of the second idler member and the second idler member is released. Therefore, when the stop operation is instructed from the winding / fast-forwarding operation, the engagement between the two idlers and the reel disk can be instantly released by moving the sliding member. No unreasonable load is applied. Further, the two idlers have a simple structure in which they are normally restricted by the elastic force of the elastic member so as not to engage with either the supply reel or the take-up reel disk, but they are made to respond immediately to the movement of the sliding member. You can and never malfunction.

[Brief description of drawings]

FIG. 1 is a plan view showing a main part of an embodiment of the present invention, FIG. 2 is a plan view showing a cam gear driving unit, FIG. 3 is a plan view showing a surface of a cam gear, and FIG. 4 is a cam gear. FIG. 5 is a plan view showing the back surface of FIG. 5, FIG. 5 is a plan view showing a reel drive mechanism, FIG. 6 is a plan view showing an engaging portion between a one-way clutch and a second sub-slider, and FIG. 7 is a side view of FIG. , FIG. 8 is a side view schematically showing a reel drive system, and FIG. 9 is a plan view showing a back surface of an idler support plate in a reel drive switching section.
FIG. 10 is a plan view showing the reel drive switching unit with the idler support plate removed, and FIG. 11 is a timing chart showing the relationship between the cam gear and the switching timing of various operations. In the drawings, 1 is a cam gear, 32 is a front cam groove, 33 is an upper guide pin, 35 is a mode lever, 39 is a mode slider,
93 is a first sub-slider, 101 is a second sub-slider, 144 is an idler roller, 145 is an idler plate, 147 is a fast forward / rewind lever, 150 is a locking pin, 151 and 173 are notches, 158 is an idler gear, 159 is a pivot plate, 168 is a pivot lever, and 172 is an engagement pin.

Claims (4)

[Claims] 1. A reel drive mode switching mechanism of a video tape recorder for switching a tape at a constant speed during a recording / reproducing operation and at a high speed during a winding / fast-forwarding operation, in a reel drive mode switching mechanism. Alternatively, a first idler member that selectively engages the take-up reel disks to rotate these reel disks at the constant speed, selectively engages the capstan motor and the supply or take-up reel disk. In combination, the second idler member for rotating these reels at high speed and the elasticity for elastically restricting the first and second idler members so as not to always engage with either the supply or take-up reel disk. Member and the first
And a part of the second idler member, and when moving in the horizontal direction, the restriction of at least one of the first and second idler members is released against the elastic force of the elastic member, and the capstan motor A mode slider for transmitting the rotation of the disk to at least one of the supply or take-up reel disk, and means for moving the mode slider in conjunction with operations such as the recording, reproducing, winding, and fast-forwarding. The mode slider includes a first sub-slider having a cam surface for controlling a position of the first idler member formed in a portion engaging with a part of the first idler member, and the first sub-slider.
A second surface, which is slidably supported on the sub-slider and movably in conjunction therewith, and a cam surface for controlling the position of the second idler member is formed in a portion that engages with a portion of the second idler member. A one-way clutch configured by a sub-slider and driven by the mode slider moving means to move the second idler member and the supply or take-up reel disk to disengage the second sub-slider. A reel drive mode switching mechanism for a video tape recorder, further comprising: 2. The method according to claim 1, wherein
The idler member has a first idler and a first idler support plate that rotatably supports the first idler, and the second idler member is positioned below and opposite the first idler member, A second idler and a second idler support plate that rotatably supports the second idler,
A reel drive mode switching mechanism for a video tape recorder in which a part of each of the first and second idler support plates is engaged with the mode slider. 3. The method according to claim 1, wherein
The sub-slider engages with a shift member that elastically shifts the second sub-slider in one moving direction, and engages with the first sub-slider when the second sub-slider moves in the other direction. A lock member that locks the second sub-slider so that the second sub-slider also moves against the deviation member. By releasing the lock member, the second sub-slider supplies or winds the second idler member. A reel drive mode switching mechanism for a video tape recorder that is positioned so that it does not engage any of the take-up reel discs. 4. The first aspect according to claim 1
A reel drive mode switching mechanism for a video tape recorder in which the idler is an idler gear having teeth formed on its outer peripheral edge, and the second idler is composed of an idler roller whose outer peripheral edge is made of a material having a high friction coefficient.