JPH0535464Y2 - - Google Patents

Description

[Detailed Description of the Invention] (Field of Industrial Application) The present invention relates to a drive device for a reel stand for running a magnetic recording tape in a video tape recorder, etc. More specifically, the present invention relates to a drive device for a reel stand for running a magnetic recording tape in a video tape recorder, etc. The reel drive motor performs fast forwarding, rewinding, and rewinding playback (the tape runs in the opposite direction to the normal playback mode and at a higher speed than the tape speed in the playback mode; the same applies hereinafter). The present invention relates to a reel stand driving device.

(Conventional example) A conventional reel stand drive device has an oscillating idler mechanism connected to a reel drive motor between a take-up reel stand and a supply reel stand, and the rotation direction of the motor can be switched and the swing idler mechanism connected to the reel drive motor can be switched depending on the motor characteristics. It swings the idler and rotates the reel stand.

However, as mentioned above, in the conventional example that utilizes the characteristics of the reel drive motor, playback, fast-forward playback (for example, 7 times the speed of playback), rewind playback (for example, 7 times the speed of playback),
When the tape is running at double speed (in the opposite direction of playback), the tape is fed by the capstan at a constant speed depending on the mode. Therefore, the number of rotations of the reel, that is, the number of rotations of the reel drive motor, is determined by the winding diameter of the tape. Therefore, the tension of the tape at this time is determined by the characteristics of the reel drive motor, and it is necessary to stabilize the characteristics of the reel drive motor from low speed rotation during playback to high speed rotation during fast forward playback and rewind playback, and to adjust the tension appropriately. It is important to set the characteristics, but this was extremely difficult.

In particular, it is difficult to ensure motor characteristics during low-speed rotation, that is, during reproduction.

The present invention discloses a reel stand driving device that solves the above problem by rotationally driving a take-up reel stand by a capstan motor during playback.

(Means for solving the problem) The supply reel stand 2 is connected between the take-up reel stand 1 and the supply reel stand 2 during the rewind mode and the rewind playback mode.
An idler 42 is provided to rotate the take-up reel stand 1 in the fast-forward mode.

A support plate 61 is slidably provided near the take-up reel stand 1, and a rotation transmission member 6 that can come into contact with and separate from the take-up reel stand 1 by sliding the support plate 61 is provided on the support plate 61.

An intermediate transmission member 7 is provided between the capstan shaft 8 and the rotation transmission member 6 to transmit the rotation of the capstan shaft 8 to the rotation transmission member 6. The rotation transmitting member 6 on the support plate 61 is moved by sliding the support plate 61 by switching the mode, and in the playback mode and the fast forward playback mode.
A switching member 3 is provided for bringing the winding reel into contact with the take-up reel stand 1. From the capstan shaft 8 to the take-up reel stand 1
A slip mechanism 60 that slips when a high load is applied is incorporated into the rotation transmission system between the two.

(Operation and Effect) Due to the function of the switching member 3, during playback or fast-forward playback, stable rotational force of the capstan shaft 8 is transmitted to the take-up reel stand 1 via the intermediate transmission member 7 and the rotation transmission member 6, and the take-up reel is Since the stand 1 is rotationally driven, the reliability of low-speed rotation of the take-up reel stand 1 during playback can be improved.

(Embodiment) In FIG. 1, a take-up reel stand 1 is provided on the right side, and a supply reel stand 2 is provided on the left side.

The take-up reel stand 1 is formed into two stages, upper and lower, as shown in FIG. 7, and a tooth surface 11 is formed on the outer periphery of the upper stage.

The oscillating idler mechanism 42 installed between the take-up reel stand 1 and the supply reel stand 2 was developed in 1987-
As disclosed in No. 17651, idler 42
is rotatably supported by a shaft 44 protruding from an idler holding plate 43 as shown in FIG. axis 4
A ring 45 is fitted to the upper end of the idler 4, and the idler 42 is urged downward by a repulsion spring 46 interposed between the ring 45 and the idler 42.
A suitable friction force is applied between the idler 42 and the idler holding plate 43 via a friction member 47 such as felt fixed to the lower surface of the idler 42. As shown in FIG. 5, the idler holding plate 43 has a substantially circular main portion and a protruding portion 4 protruding from the main portion.
3a, a guide protrusion 43b is formed on the lower surface of the protrusion 43a, and retaining guide pieces 43c are formed on both sides of the circular main body, and a hole 43d is formed in the center of the main body. ing. The guide protrusion 43b has a guide groove 49 formed in the width direction of the receiving plate 48 on the chassis.
The guide pieces 43c and 43 are fitted in to prevent them from coming off.
c is inserted into a bifurcated hole 48a formed in the receiving plate 48, and then bent toward the back surface of the receiving plate 48, and serves to prevent removal in a direction perpendicular to the surface of the receiving plate 48.

A boss 4 is installed around the hole 43d of the idler holding plate 43.
3e is formed, and the boss 43e is connected to the hole 4 of the receiving plate 48.
8a so as to be slidable.

A motor 40 is attached to the lower surface of the receiving plate 48,
An idler 42 is in contact with the rotating shaft 41 of the motor 40,
The idler 42 is connected to the rotating shaft 4 by a weak spring 46a.
It is biased towards the 1st side.

The idler 42 is located at approximately the same height as the lower outer peripheral surfaces of the two reel stands 1 and 2, and when the motor rotation shaft 41 rotates clockwise in FIG.
Due to the frictional force of the rotating shaft 41, the idler 42 is displaced toward the take-up reel stand 1 on the right side and comes into contact with the reel stand 1.

When the motor rotation shaft 41 rotates counterclockwise, the idler 42 moves to the left supply reel stand 2, contrary to the above.
be in contact with

In the drawing, a capstan shaft 8 is disposed above the take-up reel stand 1, and the shaft 8 is directly connected to a dedicated motor (not shown), and a gear 81 is fitted and fixed thereto.
A rotation transmission member 6 is disposed between the take-up reel stand 1 and the capstan shaft 8 so as to be able to come into contact with and separate from the take-up reel stand 1, and an intermediate transmission member 7 that transmits the rotation of the capstan shaft 8 to the transmission member 6 is provided. It is deployed.

The rotation transmission member 6 has a shaft 62 protruding from a support plate 61 disposed so as to be movable toward and away from the take-up reel base 1.
A large gear 63 and a small gear 62 are rotatably fitted on the shaft 62 via a friction member 67 such as felt, and both gears 63, 62 are held in place by a spring (not shown).
2 are biased in a direction toward each other, and a slip mechanism 60 is incorporated in which, when a high load is applied, the small gear 62 rotates freely and the rotation is not transmitted to the large gear 63.

The support plate 61 is urged toward the take-up reel stand 1 and the intermediate transmission member 7 by a spring 65.

The intermediate transmission member 7 has a large gear surface 72 and a small gear surface 73.
It is composed of a gear body 71 formed coaxially with the gear body 71 and an idler gear 74 that can mesh with the pinion surface 73 of the gear body 71 and can mesh with the pinion 64 of the rotation transmission member 6.

A pinch roller lever 5 having a pinch roller 51 at its tip is rotatably disposed on the chassis so that the pinch roller 51 faces the capstan shaft 8.

The actuating piece 52 is connected to the pivot part of the pinch roller lever 5.
The operating piece 52 is actuated by the switching member 3 to swing the pinch roller lever 5 and bring the pinch roller 51 into contact with and away from the capstan 8.

The switching member 3 is a plate-shaped member that is slidably disposed below the take-up reel stand 1 and the supply reel stand 2 in FIG. The left end is the slide drive device 3
It is connected to 1.

The slide drive device 31 has a spiral groove 33 that gradually moves away from the rotation center on a rotary plate 32 connected to a motor (not shown), and a switching member 3 is inserted into the groove 33.
A protruding shaft 34 protruding from is fitted in a swingable manner.

A mode detection switch plate 9 is disposed close to the transition path of the switching member 3, and the switch plate includes a playback and fast forward playback position switch 91, a rewind playback position switch 92, and a fast forward and rewind playback position switch in the direction of movement of the switching member 3. Position switch 93, stop position switch 94
is in place.

The switching member 3 is provided with a protrusion 35 for operating each of the switches 91-94.

When each mode selection switch (none of which is shown) on the mode selection panel is pressed, the drive device 31 is activated, and when the protrusion 35 of the switching member 3 matches the mode detection switches 91 to 94 corresponding to the selected mode, the drive device is activated. 31 The switching member 3 therefore stops.

The operating piece 52 of the pinch roller lever 5 and the switching member 3 are connected by a spring 36, and the pinch roller lever 5 connects the pinch roller 51 to the capstan shaft 8.
It is urged in the direction of pressing to the side.

Further, the switching member 3 is provided with a pressing piece 37 that comes into contact with the operating piece 52 of the pinch roller lever 5 when the switching member 3 slides, and swings the pinch roller 51 away from the capstan shaft 8.

The pressing piece 37 of the embodiment is formed by screwing an adjustment screw 37a onto a support piece 37b bent on the switching member 3, and can adjust the swing timing of the pinch roller lever 5 with respect to the sliding of the switching member 3.

A lever 6 whose substantially central portion is rotatably supported by a chassis between the switching member 3 and a support plate 61 that pivotally supports the rotation transmitting member 6 in the vicinity of the take-up reel stand 1.
6 is provided, one end 66a of the lever 66 abuts on a contact piece 60 protruding from the support plate 61, and the other end 66
b projects into the transition path of the protrusion 39 formed on the switching member 3. Next, the operation of the reel stand driving device will be explained for each mode.

[Playback mode/Fast forward playback mode]

As shown in FIG. 1, the idler 42 is in a neutral position where it is not in contact with either the take-up reel stand 1 or the supply reel stand 2 (the reason why this state can be maintained will be described later).

The switching member 3 is located at the rightmost position, and the switching member 3
Pinch roller lever 5 connected by 3 springs to
is urged toward the capstan 8 by the spring 36, and presses the tape (not shown) hooked on the pinch roller 51 against the capstan shaft 8.

The support plate 61 that pivots the rotation transmission member 6 is supported by the spring 6
5, the small gear 64 of the rotation transmission member 6 is biased toward the idle gear 74 of the intermediate transmission member 7, and the large gear 63 is biased toward the tooth surface 11 of the take-up reel base 1.
mesh with.

Therefore, the rotation of the capstan shaft 8 is transmitted to the take-up reel stand 1 via the intermediate transmission member 7 and the rotation transmission member 6, rotationally driving the reel stand 1, and the supply reel stand 2, cylinder (not shown), and capstan. The tape is wound up through the shaft 8 and played back.

During fast-forward reproduction, the capstan shaft 8 rotates at high speed, and therefore the take-up reel stand 1 also rotates at high speed. The capstan shaft 8 rotates at a constant speed according to the mode, and the rotation of the take-up reel stand 1 changes depending on the tape winding diameter, but the rotation transmission path from the capstan shaft 8 to the take-up reel stand 1 Since the slip mechanism 60 is provided, the tape can be wound with a constant torque even if the rotation speed of the reel stand changes depending on the tape winding diameter.

[Rewinding and reproducing] As shown in FIG. The switching member 3 remains stationary. At this time, the tension spring 36 connecting the pinch roller lever 5 and the switching member 3 is shortened by the amount of movement of the switching member 3, and the spring force is somewhat weakened, but the tape is pressed against the capstan shaft 8 by the pinch roller 51. maintain the condition.

Due to the movement of the switching member 3, the protrusion 39 of the member
hits the lever 66 that drives the support plate 61 and rotates the lever 66 slightly clockwise in FIG.
This causes the support plate 61 to slide in the direction away from the take-up reel stand 1.

The rotation transmission member 6 on the support plate 61 is disengaged from the idle gear 74 and the take-up reel stand 1, and the rotation of the capstan shaft 8 is not transmitted to the take-up reel stand 1.

On the other hand, the motor 40 of the oscillating idler 42 rotates, and the motor shaft 41 in contact with the idler 42 rotates counterclockwise.

The idler 42 moves toward the supply reel stand 2 due to the rotational frictional force with the motor shaft 41, contacts the reel stand 2, and transmits the rotation of the motor shaft 41. As a result, the tape is played back while being rewound onto the supply reel stand 2.

[Rewind mode/Fast forward mode]

As shown in FIG. 3, the switching member 3 further moves to the left from the rewinding and reproducing state. In this state, the pressing piece 37 of the switching member 3 presses the operating piece 52 of the pinch roller lever 5 to rotate the pinch roller lever 5 slightly clockwise, thereby separating the pinch roller 51 and hence the tape from the capstan shaft 8. The rotation transmission member 6 is in a position where it does not engage with the take-up reel stand 1.

As long as the oscillating idler 42 is in contact with the supply reel stand 1, it transmits the high-speed rotation of the motor shaft 41 in the counterclockwise direction to the reel stand 2, thereby performing rewinding.

In the fast-forward mode, the motor shaft 41 rotates clockwise, and the idler 42 moves to the right to come into contact with the take-up reel stand 1 and drive the reel stand 1 to rotate at high speed.

[Stop mode]

As shown in Fig. 4, the switching member 3 moves to the rightmost end, and the pinch roller lever 5 rotates significantly clockwise to move the pinch roller 51 far away from the capstan shaft 8, which prevents the unloading and loading tape from being pulled out. I'm trying not to.

The reason why the oscillating idler 42 can maintain a neutral state when it is separated from both the take-up reel stand 1 and the supply reel stand 2 as shown in FIG. 1 is because the idler 42 is in contact with either one of the reel stands. Taking FIG. 1 as an example, when the reel stand rotates counterclockwise from the state where the idler 42 is in contact with the supply reel stand 2, the idler 42 is slightly bounced away from reel stand 2.

Although the idler 4 is constantly urged toward one of the reel stands by a weak spring 46a having a snap action action, the idler 42 is mounted on a holding plate 43 via a friction plate 47. Therefore, once it is separated from the reel stand, the friction plate acts as a resistance and does not return to its original position naturally, and as the motor rotation shaft 41 rotates, the shaft 41
The reel is displaced in the direction of rotation and touches the reel stand.

[Brief explanation of the drawing]

FIG. 1 is a plan view of the reel stand drive device in the playback/fast-forward playback mode, FIG. 2 is a plan view of the rewind playback mode shown above, and FIG. 3 is a plan view of the rewind/fast-forward mode shown above. Fig. 4 is a plan view of the main part in the same stop mode as above, Fig. 5 is a perspective view of the holding plate, Fig. 6 is a sectional view of the oscillating idler structure, and Fig. 7 is the engagement of the rotation transmission member and the intermediate transmission member. It is a side view of a state. 3...Switching member, 6...Rotation transmission member, 7...
Intermediate transmission member, 8...capstan shaft.

Claims (1)

[Scope of utility model registration request] A reel drive motor 40 is connected and disposed between the take-up reel stand 1 and the supply reel stand 2, and in the rewind mode and rewind playback mode (the tape is moved in the reverse direction at a higher speed than the tape speed in the normal playback mode). an idler 42 that rotates the supply reel stand 2 (running) and rotates the take-up reel stand 1 in the fast-forward mode;
The support plate 61 is freely rotatably disposed on a support plate 61 that is slidably provided near the take-up reel stand 1.
a rotating member 6 that can come into contact with and separate from the take-up reel stand 1 by sliding; and an intermediate transmitting member 7 disposed between the capstan shaft 8 and the rotation transmitting member 6 and transmitting the rotation of the capstan shaft 8 to the rotation transmitting member 6. and a switching member 3 that is connected to the drive device 31 and moves by mode switching to slide the support plate 61 and bring the rotation transmission member 6 on the support plate 61 into contact with the take-up reel stand 1 in the playback mode and fast forward playback mode. and,
A reel stand drive device comprising a slip mechanism 60 that is incorporated into a rotation transmission system between the capstan shaft 8 and the take-up reel stand 1 and slips when a high load is applied.