JPS6314356A - Reel drive mode switching mechanism for video tape recorder - Google Patents

Abstract

PURPOSE:To prevent an irrational load from being exerted to a tape by moving a slide member so as to release momentarily the engagement between the idlers and reel disks, when stop motion is instructed while take-up/fast forwarding motion is advancing. CONSTITUTION:In instructing stopping from the fast feed/rewinding operation, the engagement between a notch projection 112 of the 2nd sub slider 101 and an engagement piece 113 of a 1st sub slider is released by a one-way clutch 117 and a 2nd sub slider 101 is moved momentarily in the right direction by a coil spring 104. Thus, a support shaft 150 is parted from the side ridge of the 1st sub slider 93, driven counter clockwise by the elastic force of the spring 149, the idler support plate 145 is moved in the direction of the ode slider 39, the engagement between the idler 144 and a gear disk 154 is released thereby releasing the fast forwarding/rewinding mode of reel drive momentarily. Thus, even if reel disks 16, 17 being driven at a high speed are stopped momentarily, the torque due to the moment of inertia of the capstan wheel is not delivered to the reel disks 16, 17 and no excess load is exerted onto the tape.

Description

[Detailed Description of the Invention] [Field of Industrial Application] This invention relates to a small home video tape recorder;
To be more specific, it relates to a mechanism that switches the drive mode of each reel so that the take-up reel rotates at a constant speed during recording/reproduction, and the supply or take-up reel rotates at high speed during one winding/fast forwarding. Background In video tape recorders, the recording/playback mode (
There are two modes: play mode (hereinafter referred to as play mode) and winding/fast-forward mode. Normally, in the play mode, a clutch mechanism is provided in the drive system to wind the tape at a constant speed, and in the single wind/fast forward mode, a mechanism is provided that directly connects the drive system and the reel disk to rotate at high speed. There is.

In other words, in a conventional video tape recorder, an idler roller that selectively engages with two reel disks, a play mode gear, and a winding/fast forward mode gear are coaxially provided via a clutch mechanism. , an intermediate rotating body that engages with the idler roller and transmits its rotation;
A mode switching gear that selectively engages with the play mode gear and the winding/fast forward mode gear, and a drive source that rotates the mode switching gear are provided. In the play mode, the mode switching gear moves up and down and meshes with the play mode gear, rotates the intermediate rotating body, and causes the idler to rotate the reel disk on the winding side. Winding/
When in fast-forward mode, the mode switching gear meshes with the gear for winding/fast-forward mode, rotates the intermediate rotating body, and the idler controls the reel disk on the supply side when in winding mode, and the winding when in fast-forward mode. When you perform a stop operation from 0 winding/fast-forwarding mode, which rotates the side reel disc, the brake operates and the reel disc stops instantly, but the mode switching gear changes from the winding/fast-forwarding mode gear to the play mode. The reel drive system is in play mode. Therefore, the fact that the reel drive is in play mode means that even if the capstan motor is stopped, due to the inertia of the capstan flywheel, etc.
Rotational force is applied to the reel disc on the side that the idler is in contact with. Therefore, there is a drawback that an extra load is placed on 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 to use a simple structure to stop the reel disk from rotating at high speed. To provide a reel drive mode switching mechanism in a video tape recorder that instantly stops a disk and prevents excessive load from being applied to the tape when stopping.

[Structure of the Invention] The reel drive mode switching mechanism of the video tape recorder of the present invention selectively engages a one-rotation drive source and a supply or take-up reel disk, and rotates these reels at a constant speed. a second idler member that selectively engages the idler member and the rotational drive source and the supply or take-up reel disk to rotate these reels at high speed;
an elastic member that elastically restricts the first and second idler members from engaging with either the supply or take-up reel disk at all times; a slider for releasing the restriction of at least one of the first and second idler members against the elastic force of the elastic member and transmitting the rotation of the drive source for one rotation to at least one of the supply or take-up reel disk; It has a moving member and means for moving the sliding member in conjunction with operations such as recording, playback, winding, and fast forwarding.

[Example] Hereinafter, an example of the present invention shown in the drawings will be described. The video tape recorder in this embodiment has six modes: fast forward, seven backward, stop, tape loading, pause, review, and play.
These modes are switched by a cam gear 1 shown in FIGS. 1 to 4, which has cam grooves on its upper and lower surfaces.

First, the drive mechanism of the cam gear 1 will be described. A power support plate 3 is provided on the lower surface of the base plate 2, and a DC motor 4 is attached to the power support plate 3. A first pulley 6 is attached to the drive shaft 5 of the motor 4, and a first endless belt 7 is stretched around the first pulley 6. This first endless belt 7 also has
The second pulley 8 has a larger diameter than the first pulley 6, and the second pulley 8 is attached to a rotating shaft 9 rotatably supported by the power support plate 3.

The rotating shaft 9 further includes a third pulley having a smaller diameter than the second pulley 8.
A pulley 11 is attached. A second endless belt 14 is stretched between the third pulley 11 and a fourth pulley 13 which is attached to a worm shaft 12 and which is rotatably supported by the power support plate 3 and has a larger diameter than the third pulley 11. A worm gear 15 is attached to the worm shaft 12,
This worm gear 15 meshes with a gear 87 provided on the outer periphery of the cam gear 1.

The cam gear 1 is rotatably supported on a shaft 88 of the power support plate 3.

Therefore, the rotation of the motor 4 is controlled from the first pulley 6 to the first
It is transmitted to the second pulley 8 via the endless belt 7, and the one-rotation shaft 9 rotates at a reduced speed. This deceleration rotation is caused by the third pulley 11. It is transmitted to the fourth pulley 13 via the second endless belt 14, causing the fourth pulley 13 to rotate at a further reduced speed. The rotation of the fourth pulley 13 causes the worm shaft 12 to rotate, and this rotation also causes the cam gear 1 to rotate. Rotation of the cam gear 1 controls various operating modes described below.

First, I will explain tape loading. The tape loading mechanism is controlled by a back cam groove 21 provided on the back surface of the cam gear 1 and extending from the center toward the outer periphery, as shown in FIG. The back cam groove 21 has a first portion 21p-q extending concentrically from its center, a second portion 21q''r that gradually widens from the first portion 21q toward the outer periphery, and a second portion 21q''r that extends concentrically from the center thereof. The third portion extends gradually from the portion 21r toward the outer periphery.
a portion 21r-s, and a fourth portion 21 extending from this third portion 21g so as to gradually expand further in the outer circumferential direction.
s to t and a fifth portion 21t=u extending concentrically from the fourth portion 21t are formed continuously and in a spiral shape.

The upper end of the lower guide pin 22 is loosely fitted into the back cam groove 21 of the cam gear 1. The lower end of this guide pin 22 is fixed to a partially toothed gear plate 23.

The partially toothed gear plate 23 is rotatably attached to the power support plate 3 at its rear end by a support pin 24 .

Rack teeth 25 are provided on the tip end surface of the partially toothed gear plate 23. This rack tooth 25 meshes with a tenth deng gear 26 , which in turn meshes with a twentieth deng gear 27 . The first and twentieth loading gears 26 and 27 are provided on the base plate 2, as shown in FIG. There is. Two guide grooves 29 are provided on the loading plate 28 so as to surround the rotary head, and a pole base 31 is attached to each groove 29 so as to be movable along these grooves 29. A loading post 10 for pulling out the tape is erected on these pole bases 31. These pole bases 31 include
An arm mechanism (not shown) linked to the first and 20th loading gears 26.27 pulls out the tape from the tape cassette in conjunction with the rotation of the loading gear 26.27, and rotates the outer circumference of the rotating head approximately 190 degrees. It is for wrapping around. Since a conventional arm mechanism can be used, a detailed explanation and drawings thereof will be omitted.

As described above, the first portions 21 p - q of the back cam groove 21 of the cam gear 1 are formed concentrically, so even if the cam gear 1 starts rotating, the upper guide pin 22 will not move from this first portion 21 . While positioned at p-q, the partially toothed gear plate 23 cannot pivot. When the cam gear 1 further rotates and the upper guide pin 22 is positioned at the second portion 21q-r, the upper guide pin 22 The partially toothed gear plate 23 rotates about the support pin 24 as a fulcrum, and the first and twentieth gears 26
．． 27 also rotates. As a result, the pole base 31 moves forward along the guide groove 29. As the pole base 31 moves forward, the upper guide pin 22
section 21r-s and the fourth section 21s"v. When the guide pin 22 reaches the fourth section 21v, the pole base 31 hits a stopper (not shown), and then the guide pin 22 moves to the fourth section 21s"v. When located at the fourth section 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.The fifth section 21t''u is located at the first section 21p-q.
Since the upper guide pin 22 does not move in the outer circumferential direction, the partially toothed gear plate 23 does not pivot even if the cam gear 1 rotates.

Transmission to other mechanical elements is performed by a front cam groove 32 extending spirally from the center toward the outer periphery on the surface of the cam gear 1, as shown in FIG. The front cam groove 32 extends concentrically from its center, and includes a first portion 32a=b for fast forwarding and rewinding, and a second portion 32b that gradually expands in the outer circumferential direction from this first portion 32b. -c, and a third stop extending concentrically from this second portion 32c.
A portion 32c''d, a fourth portion 32d-e extending from the third portion 32d so as to gradually expand in the outer circumferential direction, and a fifth portion 32e extending concentrically from the fourth portion 32e = f , sixth portions 32f to 32g linearly extending outward from this fifth portion 32f, and this sixth portion 32
A seventh portion 32 for the pose extends concentrically from g.
g-h, an eighth portion 32h-i extending from the seventh portion 32h so as to gradually expand in the outer circumferential direction, and a ninth portion for review extending concentrically from the eighth portion 321. a portion 32i=j, and a tenth portion 3 extending from this ninth portion 32j so as to gradually expand in the outer circumferential direction.
2j-k, extending concentrically from the tenth portion 32k, and ~1 to the eleventh portion 32 for play are formed continuously and spirally.

The lower end of the upper guide pin 33 is loosely fitted into the front cam groove 32 of the cam gear 1 . The upper end of this upper guide pin 33 projects onto the substrate 2 through a guide groove 34 provided in the substrate 2 so as to be located above the cam gear 1 and extend from the center to the outer circumference of the cam gear 1. ing. The upper end of the upper guide pin 33 is press-fitted into one end of the mode lever 35. The intermediate portion of the mode lever 35 is rotatable about a pivot pin 36 fixed to the base plate 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 into this long hole 37.

This pin 38 is provided upright on one end of a mode slider 39 extending in the frontage direction on the substrate 2.

The mode slider 39 has two guide holes 20 extending in the longitudinal direction at both ends thereof, and by fitting pins 30 erected on the substrate 2 into these guide holes 20, the mode slider 39 can be slidably attached to the substrate 2. The top nine is supported. In FIG. 1, the stopped state is shown, and the lower end of the upper guide pin 33 is located within the third portions 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 portions 32c to 32d to the second portions 32b to 32c. I will have to 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 7 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 portions 32c to 32d to the fourth portion.
The upper guide pin 33 moves to the portion 32d=e, and the upper guide pin 33 moves in the outer circumferential direction. This causes the mode lever 35 to rotate counterclockwise, and the mode slider 39 to move to the right.
The recording/playback mode (hereinafter referred to as play mode) is entered.

Next, to explain the case of the play mode, the cam gear 1 rotates from the stopped state shown in FIG. The lower end is the front cam groove 3
2, and moves from there to the 11th section 32 to -1. With this movement, the mode lever 35 rotates clockwise about the pivot pin 36. Then, move the mode slider 39 to the right in FIG. The upper end of the upper guide pin 33 projecting upwardly from the mode lever 35 is engaged with the upper side edge of a tension arm 42 in FIG. 43, it is rotatably supported by the substrate 2. A support lever 18 is also pivotally attached to the tension arm 42 and includes a tension band 1
9 is attached at one end. This tension band 1
The other end of the supply reel disk 9 is wound around the outer periphery of the supply reel disk 16 and then fixed to the substrate 2.

A coil spring 4 is attached to one end of the tension arm 42.
4 is attached at one end, and a tape guide post 45 is erected at the other end. coil spring 44
The other end is attached to the base plate 2 so that the tension arm 42 applies rotational force in a counterclockwise direction using a pin 43 as a fulcrum. Therefore, by 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 on the upper side edge of the tension arm 42. Thereafter, it rotates counterclockwise following the movement of the upper guide pin 33. By rotating the mode lever 35 in the counterclockwise direction, the tension band 19 is wound around the outer periphery of the supply reel disk 16 to obtain a predetermined pack tension, and the tape guide post 45 is positioned at a predetermined position in the pre-temporary position, and the tape to give a predetermined tension.

On the other hand, as 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 right. This pin 46 has a substantially middle portion
The first pinch roller lever 48 is loosely fitted into an elongated hole 49 provided at one end of a first pinch roller lever 48 which is rotatably supported by a pinch roller lever 7 . One end of each of two overlapping link plates 51 (only the upper link plate is shown in FIG. 1) is rotatably attached to the intermediate portion of the first pinch lawn lever 48. The two link plates 51 each have elongated holes 52 inside thereof, and pressure springs 53 are inserted into these elongated holes 52. One end of the upper link plate 51 is rotatably supported with respect to the first pinch roller lever 48 by a pin 54, and a long hole 55 is formed in the other end. A pin 57 erected on the lower surface of one end of the second pinch roller lever 56 is loosely fitted into the second elongated hole 55 . The lower end of the pin 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 a pin 54 is loosely fitted into this elongated hole.

The second pinch roller lever 56 has a pivot pin 5 located approximately in the middle.
8 is fixed and rotatably attached to a bearing (not shown) attached to the substrate 2. Pivot pin 58
The second pinch roller lever 56 rotates using the fulcrum as a fulcrum.

A pinch roller 5 is attached to the other end of the second pinch roller lever 56.
9 is rotatably supported. Therefore, the pinch roller 59 is always elastically pressed in the direction of the capstan shaft 61 by the pressing spring 53 of the link plate 51Fl, and as the mode slider λ9 moves to the right, the first pinch roller lever 48 rotates counterclockwise,
The ring plate 51 is pushed up in the L direction, whereby the second pinch roller 56 also rotates counterclockwise and the pinch roller 59 is pressed against the capstan shaft 61.

Next, the supply reel disk 16 and the take-up reel disk 17
The brake mechanism will be explained with reference to FIG. The supply reel disc 16 is provided with a main brake arm 152 and a sub brake arm 63.

Although not shown, the main brake arm 62 has a friction material made of rubber or synthetic resin with a high coefficient of friction attached to one end, and this friction material is attached to the reel disc 1.
A brake bar 64 that stops rotation by coming into pressure contact with the outer peripheral surface of the brake bar 64, and a connecting bar 65 whose one end is located approximately in the middle of the brake bar 64 and whose extending direction is orthogonal to the extending direction of the brake bar 64. It is integrally formed. At the intersection of the brake par 64 and the connecting bar 65, a pivot pin 67 whose lower end is fixed to the brake support plate 66 is pivotally attached. An engagement pin 68 is also provided upright on the brake par 64. The sub brake arm 63 is
A friction material such as felt is attached to one end (not shown), and this friction material is attached to the reel disk 16.
It stops rotation by pressing against the outer peripheral surface of the shaft, and is approximately U-shaped. The other end of the auxiliary 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 erected near the pivot pin 69, and one end of a coil spring 72 is attached. coil spring 7
The other end of 2 is attached to a locking hook 73 fixed to the brake support plate 66, and the auxiliary brake arm 63 is elastically pulled by a coil spring 72 so that the friction material comes into pressure contact with the outer peripheral surface of the reel disc 16. There is.

The brake mechanism of the take-up reel disk 17 also includes a main brake arm 74 and a sub-brake arm 75, similar to the brake mechanism on the supply reel disk 16 side. Although not shown, the main brake arm 74 has a friction material made of rubber or synthetic resin with a high friction coefficient attached to one end thereof, and this friction material comes into pressure contact with the outer peripheral surface of the reel disc 17 to stop the rotation. , a connecting bar 77 whose one end is located approximately in the mountainous area of the brake par 76 and whose extending direction is orthogonal to the extending direction of the brake par 76.
are integrally formed. At the intersection of the brake par 76 and the connecting bar 77, a pivot pin 78 whose lower end is fixed to the brake support plate 66 is pivotally attached. Brake par 76 again. An engagement pin 79 is provided upright. The auxiliary brake arm 75, like the auxiliary brake arm 63 on the side of the supply reel disc 16, has a friction material such as felt attached to one end (not shown), and has an abbreviated shape. The other end of the auxiliary brake arm 75 is pivotally attached to a pivot pin 81 whose lower end is fixed to the brake support plate 66 . An engagement 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. 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. It is pulling to A pair of locking posts 84.85 are formed on the upper surface of the other end of the connecting bar 77, and the locking posts 84.85 are spaced apart from each other. The other end is loosely clamped. A coil spring 8 is installed between one end of each of the brake pars 64 and 76 to which the friction material is attached and the opposite end.
6 is attached, and this coil spring 86 keeps one end on the friction material side always connected to each reel disk 1.
6. It is configured to be elastically pressed against the outer peripheral surface of 17.

The engagement pins 68, 71, 79 protrude upward from the notch 91 of the substrate 2, and the engagement pin 82 protrudes from the hole 92 of the substrate 2.
It protrudes upward from. These engagement pins 6h71, 7
9. The upper end of 82 slides (s!
It is adapted to change its position by aligning with the side edge of the first sub-slider 93 placed thereon. That is, the side edge of the mode slider 39 has a first notch 94 for the engagement pin 68, a second notch 95 for the engagement pin 71, and a second notch 95 for the engagement pin 82. 3 notches 96 are formed. The first notch 94 is positioned to face the engagement pin 68 when the mode slider 39 is in the stop mode as shown in FIG. 94. The second cutout portion 95 is located opposite the engagement pin 71 when the mode slider 39 is in the stop, tape loading, pause, and review modes;
In other modes, it is formed so as to be removed from the second notch 95. The third notch 96 is the second
Similar to the notch 95, the mode slider 39 is stopped.

It is formed to be located opposite the engagement pin 82 when in tape loading, pause, and review modes, and to be removed from the third notch 96 in other modes.

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. 1st sub slider 9
3 is a guide protrusion 97 formed so as to protrude downward at approximately the center of the side edge opposite to the side edge on the engagement pin 79 side;
It has an engagement pin 98 provided so as to protrude downward on the side opposite to the mode lever 35 side. The guide protrusion 97 is provided on the mode slider 39 and is loosely fitted into a long hole 99 extending in the direction of movement of the motes and rider 39. Similarly, an engaging pin 98 is also provided on the mode slider 39, although not shown. It is loosely fitted into an elongated hole that extends similarly to the elongated hole 99. On the lower surface of the end of the first sub-slider 93 on the mode lever 35 side, there is a second sub-slider 93 formed in a substantially hook shape at both ends.
A sub-slider 101 is attached. One hook-shaped end 102 of the second sub-slider 101 is exposed from the end of the first sub-slider 93, and the other hook-shaped end 103
protrudes from the side edge of the first sub-slider 93 as shown in FIG. A corner of the other hook-shaped end 103 is rotatably supported by the first sub-slider 93 by a pivot pin 106. One end of a coil spring 104 is attached to the other hook-shaped end 103, and this coil spring 104 always elastically deflects the first and second sub-sliders 93, 101 in the direction of the first pinch roller lever 48. It is something to do. Fourth notch 1 for engagement pin 79
05 is provided on this first sub-slider 93, and similarly to the first notch 94, it is located so as to face the engagement pin 82 when the mode slider 39 is in the stop mode, and in other modes. It is formed so as to be removed from this fourth notch 105 when .

To explain the operation of these brake mechanisms, when stopped, as shown in FIG. 2nd) Third and fourth notches 94.
It is opposite to 95.96.105. Since each end of the main brake arm 62, 74 is elastically pulled by the coil spring 104, the brake pad 64 of the main brake arm 62 is rotated counterclockwise about the pivot pin 67, and the main brake arm 74 is The brake pars 76 each rotate clockwise about the pivot pin 78 as a fulcrum. Due to this rotation, the friction material at the other end of the brake par 64, 76 comes into contact with the outer peripheral surface of the supply and take-up reel disk 16, 17, and the main brake is turned on. On the other hand, the auxiliary brake arms 63.75 are rotated counterclockwise about pivot pins 69.81 by coil springs 72.83, respectively, and the felt material is applied to the outer peripheral surfaces of the supply and take-up reel disks 16.17. The secondary brake is turned on.

When the motor 4 is driven and the cam gear 1 is rotated in order to shift from a stopped state to a cheap loading operation, the upper guide pin 33 moves from the third portion 32c = d of the front cam groove 32 to the fourth portion 32d''e. As a result, the mode lever 35 rotates counterclockwise, and the mode slider 39 moves rightward in FIG. slider 3
9 and rotates the brake par 64 clockwise against the elastic force of the coil spring 86. As a result, the friction material at the other end of the brake par 64 separates from the outer peripheral surface of the supply reel disk 16, and the main brake is turned off. On the other hand, the rotation of the brake par 64 is controlled by the connecting bar 6.
5 to the connecting bar 77 of the main brake arm 74 via the locking posts 84 and 85, causing the brake bar 76 to rotate counterclockwise. As a result, the main brake on the take-up reel disc 17 side is also turned off. The secondary brake side is in the on state because the engagement pin 71.82 still faces the second and third notches 95.96. The cam gear 1 continues to rotate until the pole base 31 reaches a predetermined position for tape loading, but since the fifth portion 32e''f of the cam groove 32 is formed concentrically, the upper guide pin 33 It never moves.

When the cam gear 1 further rotates to move from this tape loading operation to a play operation, the upper guide pin 33 moves from the sixth portion 32f-g of the front cam groove 32 to the final first portion 32 in the direction -Q. Along with this, the mode lever 35 further rotates counterclockwise. Therefore, the mode slider 39 further moves to the right in FIG. and rotate the auxiliary brake arm 63 clockwise against the elastic force of the coil spring 72. Similarly, the pivot pin 82 of the sub brake arm 75 on the side of the first take-up reel disc 17 rides on the side end of the mode slider 39 from the left side of the third notch 96, and resists the elastic force of the coil spring 83 to Rotate the brake arm 75 counterclockwise. As a result, the sub brake arm 6
The felt material at each other end of 3.75 is separated from the outer circumferential surface of the supply and take-up reel discs 16,17, and the auxiliary brake is also turned off.

When the motor 4 is rotated in the reverse direction in order to transition 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 leftward.

As a result, the engagement pins 71, 82 and mode slider 39
are disengaged from the side edges of the brake arm, these engagement pins 71.82 are opposed to the second and third notches 95.96, and the secondary brake arms 63.75 are rotated counterclockwise, respectively. The felt material at each other end is pressed against the outer peripheral surface of the supply and take-up reel disk 16, 17 by the elastic force of the coil spring 72) 83, and only the auxiliary brake is turned off.

When moving from a stop operation to a fast forward 7 rewind operation, the motor 4 is reversed and the cam gear 1 is also reversed.

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 take-up reel disk 17
The engagement pin 79 of the side main brake arm 74 rides on the side edge of the first sub-slider 93 from the right side of the fourth notch 105 of the first sub-slider 93, and resists the elastic force of the coil spring 86. Rotate the main brake arm 74 counterclockwise. As a result, the friction material of the brake bar 76 separates from the outer peripheral surface of the take-up reel disk 17, and the main brake is turned off. The rotation of the main brake arm 74 is transmitted from the connection bar 77 via the locking posts 84.85 to the connection bar 65 of the main brake arm 64 on the supply reel disc 16 side, and this connection 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 71.79 ride on the side edges of the mode slider 39 from the right side of the second and third notches 95.96 of the mode slider 39, and resist the elastic force of the coil springs 72.83. auxiliary brake arm 6
3.75 are rotated clockwise, the felt material is separated from the outer peripheral surfaces of the supply and take-up reel discs 16 and 17, and the auxiliary brake is also turned off.

When transitioning from the fast forward 7 rewind operation to the play operation, the supply and take-up reel disks 16, 17 are rotating at high speed and must be stopped instantaneously. Therefore, this embodiment has a mechanism as shown in detail in FIGS. 6 and 7. One hook-shaped end 102 of the second sub-slider 101 is provided with a protruding member 111 that projects downward. This protruding member 111 of the hooked end 102
A notch protrusion 112 is provided at the other end facing the other end. The notch protrusion 112 engages with an engaging piece 113 that protrudes upward from the side edge of the mode slider 39 opposite to the notch portion side when the mode slider 39 is stopped. This 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 1 are attached to the rotating shafts 9 of the second and third pulleys 8 and 11.
14 and 115, and a one-way clutch 117 having a coil spring 116 coaxially fitted between the clutch pulleys 114 and 115.

The clutch pulley 115 has an engaging piece 118 that projects outward.
is provided. The one-way clutch 117 is operated by a coil spring 116, so that when the rotary shaft 9 rotates counterclockwise in FIG. 7, the clutch pulley 114 also rotates in the same direction, but when it rotates clockwise as shown by the arrow, The clutch pulley 115 is designed to idle, and such a one-way clutch 117 is widely used in various fields.

Due to this one-way clutch 117, the first sub-slider 93 moves to the left as the mode slider 39 moves to the left, and the protruding member 111 of the second sub-slider 101 engages with the engagement piece 118 of the clutch pulley 115. Even when engaged, only the clutch pulley 115 stops, and the rotating shaft 9 continues to rotate.

When moving from the fast forward 7 rewind operation to the stop position, the motor 4 rotates in the reverse direction and the rotating shaft 9 rotates clockwise. As a result, the one-way clutch 117 is also reversely rotated, and the engagement piece 118 of the clutch pulley 115 is pushed up above the protruding member 111 of the second sub-slider 101 as shown by the arrow in FIG. In FIG. 7, the projection member 111 moves in the direction of the arrow. As mentioned above, the second sub-slider 101 is
Since it is rotatably attached to the first sub-slider 93 by the pivot pin 106, it rotates clockwise about the pivot pin 106 as a fulcrum. As a result, the engagement between the notch protrusion 112 and the engagement piece 113 is released, and the second sub-slider 101 is instantly moved to the right by the coil spring 104.

The rightward movement of the second sub-slider 101 is stopped when the guide protrusion 97 engages with the edge of an elongated hole (not shown) provided in the substrate 2. At this time, the engagement pin 79 instantly separates from the right end of the fourth notch 105, the main brake on the take-up reel disk 17 side is turned on, and the main brake on the supply reel disk 16 side is also turned on, causing the rotation to occur at high speed. The two reel discs 16 and 17 that are running stop instantly.

Next, the review operation will be described. The reviewer 121 is rotatably supported on the substrate 2 by support pins 122 at intervals. An engagement pin 123 is implanted on the lower surface of one end of the reviewer 121, and this engagement pin 123 is positioned so as to engage with the tip of the first pinch roller lever 48 when it rotates counterclockwise. are doing. The reviewer 121 is always elastically deflected counterclockwise by a spring 124, and elastically deflects the review post 125 implanted on the upper surface of the other end facing the engagement pin 123 toward the capstan 61. ing. Therefore, as the mode slider 39 moves to the right, the first pinch roller lever 48 rotates counterclockwise to resist the elastic force of the spring 124 during tape loading, pause, review, and play operations. It will rotate clockwise and operate.

Next, regarding the reel drive mechanism, Sections 5.8.9 and 10.
This will be explained using figures. Each outer periphery of the supply reel disk 16 and the take-up reel disk 17 has teeth 1 for driving the reel.
31 and 132 are provided, and the teeth 131 are meshed with outer peripheral teeth 135 of a fast forward seven rewind disk 134 rotatably attached to a support shaft 133 implanted in the brake support plate 66. A reverse playback/review gear 137 having a smaller diameter than the outer teeth 135 is coaxially provided on the fast-forward 7-rewind disk 134 via a clutch 136 . The teeth 132 mesh with outer peripheral teeth 141 of a fast-forward seven-rewind disk 139 rotatably attached to a support shaft 138 implanted in the brake support plate 66 parallel to and spaced apart from the support shaft 133. The outer peripheral teeth 135, 141 of the fast forwarding 7 rewinding discs 134, 139 are arranged so as not to mesh with each other. Fast forward 7 Rewind disc 1
Similarly, the outer tooth 14 is connected to the outer tooth 38 via the clutch 142.
A play gear 143 having a diameter smaller than 1 is coaxially provided. As shown in Fig. 8゜10, the two fast forwards 7
An idler roller 144 made of a material with a high coefficient of friction, such as rubber, is located between the unwinding disks 134 and 138.

The idler roller 144 is rotatably attached to a support shaft 140 erected at the center of a substantially cross-shaped idler support plate 145. The support shaft 146 projects downward from a long hole 130 provided in the brake support plate 66.
By a coil spring (not shown).

In FIG. 10 it has been elastically deflected upwards.

An engagement pin 146 is integrally provided at the end of the idler support plate 145 on the mode slider 39 side so as to project upward. This engagement pin 146 is engaged with one end of a fast-forward seven rewind lever 147 formed in a substantially reversed shape. The other end of the fast-forwarding 7 rewinding lever 147 is pivotally attached to a support shaft 148 erected on the brake support plate 66, and a spring 149 is used to move the fast-forwarding 7
One end of the rewinding lever 147 presses the engagement pin 146 toward the mode slider 39 against the elastic force of a coil spring (not shown). A locking pin 150 is provided upright in the middle of the fast forwarding 7 rewinding lever 147. This locking pin 150 is connected to a fifth notch 151 and a fourth notch 1 provided approximately in the center of the first sub-slider 93.
It is possible to engage with an inclined side 152 formed at the boundary of 05.

The idler roller 144 can also selectively engage with the lower outer periphery of a gear disc 154 attached to a support shaft 153 that is rotatably erected on the brake support plate 66. gear disc 154
A gear portion 155 having a smaller diameter is integrally formed. Support shaft 153 extending below the brake support plate 66
A pulley 15 is connected to the lower end of the
6 is installed.

This pulley 156 has an endless belt 15 connected to a capstan motor (not shown) for driving the tape.
It is multiplied by 7. Gear section 155 and reverse playback/review gear 137. An idler gear 158 is provided to selectively mesh with either one of the play gears 141. This idler gear 158, as shown in FIG.
It is rotatably attached to the pivot plate 159 by a support shaft 161. This pivot plate 159 is pivotally attached at one end by a pin 163 erected on the lower surface of an idler gear support plate 162 provided 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. A notch 165 (FIG. 5) is formed in the center of this sliding plate 164.
The pin 161 protrudes into the interior of the pin 65 . An engagement pin 166 projecting downward is integrally provided at the end of the sliding plate 164 on the mode slider 39 side, and one end of a coil spring 167 is attached. One end of this coil spring 167 is attached. The other end of this coil spring 167 is attached to the idler gear support plate 162 and constantly pulls the sliding plate 164 toward the mode slide 39 side. An elongated hole 169 provided at one end of a pivot lever 168 is loosely fitted into 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.

An engagement pin 172 extends downward on the lower surface of the end of the pivot lever 167 on the mode slider 39 side.

This engagement pin 172 faces a sixth notch 173 provided on the side edge of the mode slider 39 at a substantially central portion.

Therefore, when the engagement pin 172 is pressed upward in FIG. 9, the pivot lever 168 pivots about the pin 171 and pushes up the sliding plate 164 against the elastic force of the coil spring 167. The side of the notch 165 of the sliding plate 164 that faces the engagement pin 166 is inclined toward the center, and the pin 161 is held at the center at its apex. Reference numeral 174 in FIG. 5 is a guide protrusion that guides the sliding movement of the sliding plate 164.

The operation of the reel drive mechanism described above will be explained. When switching from the illustrated stop state to the play operation, the mode slider 39 moves to the right, and the engagement pin 172 runs onto the side edge of the mode slider 39 from the left end into the sixth notch 173.
Push up. As a result, the sliding plate 164 is also pushed up,
The pivot plate 159 is now free to pivot, and the idler gear 158 is also free. The idler gear 158 of the pivot plate 159 meshes with the gear portion 155 of the gear disc 154, and the pulley 156 rotates clockwise in FIG.
It meshes with the play gear 143 of the rewind disc 139 to rotate the fast forward/rewind disc 139. Since the outer teeth 141 of the fast-forwarding 7 rewinding 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.
7 and rotates this fast forward 7 rewind disk 134. Outer tooth 135 of fast forward 7 rewind disk 134
is meshed with the teeth 131 of the take-up reel disk 16, so this rotation is transmitted to the take-up reel disk 16, causing the tape to run in the opposite direction.

During these two operations, the fast forward 7 rewind lever 147
Since the locking pin 150 is located away from the inclined side 152 of the first sub-slider 93, it is rotated counterclockwise by the spring 149 to pull the idler plate 145 toward the mode slider 39. As a result, the idler roller 144 is located at the neutral position, and the fast forwarding 7 rewinding disk 1
34.139 or the gear disc 154.

In the case of fast forward operation, the mode slider 39 moves to the left, the engagement pin 172 faces the sixth notch 173 of the mode slider 39, and the pivot lever 168 rotates and slides due to the coil spring 167. The plate 164 moves toward the mode slider 39 side. As a result, the idler gear 158 performs reverse regeneration and the review gear 137. It is located at a neutral position where it does not mesh with either play gear 141 or gear portion 155. As the mode slider 39 moves to the left, the first sub-slider 93 moves to the left, and the locking pin 150 of the fast-forward 7 rewind lever 147 moves to the first sub-slider 93.
from the inclined side 152 to the side edge. Therefore, the fast forwarding 7 rewinding lever 147 rotates clockwise against the elastic force of the spring 149, and its tip and idler plate 145
is disengaged from pin 146. As a result, the idler plate 145 becomes free, and a spring (not shown) moves the idler roller 144 to the gear disc 1.
It comes into contact with the periphery of 54. In this state, when the pulley 156 rotates clockwise, the idler roller 144 comes into contact with this fast-forward 7-rewind disk 139, and this disk 13
Rotate 9. The rotation of the disk 139 is caused by the outer tooth 141.
The tape is transmitted to the winding disk 17 via the winder, and the tape is wound at a higher speed than the pre-winding speed.

In the case of a rewind operation, the pulley 156 rotates counterclockwise in the same arrangement as the fast forward operation described above. As a result, the idler plate 145 is tilted toward the fast-forward 7-rewind disc 134 via the idler roller 144, and the idler roller 144 comes into contact with this fast-forward 7-rewind disc 134.
This disk 134 is rotated.

The rotation of the disk 134 is transmitted to the supply reel disk 16 via the outer teeth 135, and the tape is rewound at high speed.

If the stop operation is performed from this fast forward 7 rewind operation.

As described above, the one-way clutch 117 disengages the notch protrusion 112 of the second sub-slider 101 from the engagement piece 113 of the first sub-slider 93, and the coil spring 104 instantly moves the second sub-slider 101 to the right. move in the direction. Therefore, the support shaft 150 moves away from the side edge of the first sub-slider 93 and rotates counterclockwise by the elastic force of the spring 149, thereby moving the idler support plate 145 in the direction of the mode slider 39. As a result, the engagement between the idler 144 and the gear disc 154 is released,
Instantly, the reel drive fast forward 7 rewind mode is canceled. At this time, since the mode slider 39 is at the fast forward 7 rewind position, the reel drive play mode also remains cancelled.

Therefore, the reel drive system is in a free state, and even if the high-speed rotating reel disk 16.17 is stopped instantaneously, the rotation due to the inertia of the capstan wheel is not transmitted to the reel disk 16.17, causing unnecessary damage to the tape. It does not impose any heavy load.

The operating states of the main components in the various operations described above, together with the movement of the cam gear 1, are summarized as shown in FIG. 11. In addition, in the main brake arm 62 and the reel drive in the fast forward 7 rewind mode, the portion indicated by the dotted line indicates the instantaneous operation due to the operation of the second sub-slider 101 described above.

[Effects of the Invention] As described above, the reel drive mode switching mechanism of the videotape recorder of the present invention selectively engages the rotational drive source with the supply or take-up reel disc, and runs these reels at a constant speed. A first idler member for rotating, a second idler member for selectively engaging a rotational drive source and a supply or take-up reel disk to rotate these reels at high speed; Second
The idler member is elastically restrained by an elastic member so as not to engage with either the supply or take-up reel disk at all times. Further, each portion of the first and second idler members engages a sliding member movably supported on the horizontal crystal, and the position of the sliding member causes the first and second idler members to resist the elastic force of the elastic member. Either or both of the first and second idler members are released. Therefore, when a stop operation is instructed from a winding/fast-forwarding operation, by moving the sliding member, the engagement between the two idlers and the reel disk can be instantly disengaged, allowing the tape to No unreasonable load will be applied. Furthermore, the two idlers have a simple structure in which they are normally restricted from engaging with either the supply or take-up reel disk by the elastic force of the elastic member, but they respond immediately to the movement of the sliding member. and will not malfunction.

[Brief explanation of drawings]

Fig. 1 is a plan view showing essential parts in an embodiment of the present invention, Fig. 2 is a plan view showing the cam gear drive section, Fig. 3 is a plan view showing the surface of the cam gear, and Fig. 4 is a plan view showing the cam gear. FIG. 5 is a plan view showing the back side of the reel drive mechanism.
The figure is a plan view showing the engagement portion between the one-way clutch and the second sub-slider, Figure 7 is a side view of Figure 6, Figure 8 is a side view schematically showing the reel drive system, and Figure 9 is a side view of the reel. FIG. 10 is a plan view showing the back side of the idler support plate in the drive switching section, FIG. 10 is a plan view showing the reel drive switching section with the idler support plate removed, and FIG. 11 shows the relationship between the cam gear and the switching timing of various operations. FIG. In the drawing, 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 the idler plate, 147 is the fast forward 7 rewind lever, 150 is the locking pin,
151.173 is a notch, 158 is an idler gear, 1
59 is a pivot plate, 168 is a pivot lever, and 172 is an engagement pin. Patent Applicant: Fujitsu General Co., Ltd. Representative Patent Attorney: Takuya Ohara Figure 2 Figure 6 Figure 7 Figure 3 Figure 4 Figure 5 Figure 8

Claims (6)

[Claims] (1) In the reel drive mode switching mechanism of a video tape recorder, which switches the tape to run at a constant speed during recording/playback operations and to run the tape at high speed during winding/fast-forwarding operations, the rotating drive source and the supply or winding a first idler member that selectively engages a take-up reel disk to rotate these reels at the constant speed; and a first idler member that selectively engages the rotational drive source and the supply or take-up reel disk; , a second idler member for rotating the reels at the high speed; and an elastic member for elastically restricting the first and second idler members from engaging with either the supply or take-up reel disk at any time; engages a portion of each of the first and second idler members, and when moved in the horizontal direction, releases the restriction of at least one of the first and second idler members against the elastic force of the elastic member; A sliding member for transmitting the rotation of the rotational drive source to at least one of the supply or take-up reel disk, and means for moving the sliding member in conjunction with the recording, reproducing, winding, fast forwarding, etc. operations. A reel drive mode switching mechanism for a video tape recorder having a reel drive mode switching mechanism. (2) In claim 1, the sliding member has a cam surface formed in a portion that engages with a portion of each of the first and second idler members, and this cam surface forms a portion of the sliding member that engages a portion of the first and second idler members. A reel drive mode switching mechanism for a video tape recorder that controls the positions of first and second idler members. (3) In claim 1, the sliding member is slidable on and interlocks with a first sliding member that controls the position of the first idler member. and a second sliding member movably supported by the reel drive mode switching mechanism for a video tape recorder, the second sliding member controlling the position of the second idler member. (4) In claim 1, the first idler member includes a first idler and a first idler support plate that rotatably supports the first idler, and the second idler member includes the first idler member. The first idler member has a second idler and a second idler support plate that rotatably supports the second idler and is located below and opposite to the first idler member, and includes a second idler support plate that rotatably supports the second idler. A reel drive mode switching mechanism for a videotape recorder, each portion of which is engaged with the sliding member. (5) In claim 3, the second sliding member includes a deflecting member that elastically shifts the second sliding member in one direction of movement; a locking member that engages with the first sliding member when moving in the other direction and locks the second sliding member so that it also moves against the deflection member; A reel drive mode switching mechanism for a videotape recorder, upon release of which said second sliding member positions said second idler member so as not to engage either said supply or take-up reel disk. (6) In claim 1, the first idler is an idler gear having teeth formed on its outer periphery, and the second idler is composed of an idler roller whose outer periphery is made of a material with a high coefficient of friction. A reel drive mode switching mechanism for a video tape recorder.