JPH02220247A - Braking mechanism - Google Patents

Abstract

PURPOSE:To stabilize the running of a tape and to perform a program searching at high speed by switching the energizing force applied to a preload brake for fast forwarding and use it also as a tension brake for reverse play. CONSTITUTION:The weak energizing force of only a preload spring 4 is applied to a brake 2 in the fast forwarding position, and the tape is run at high speed, and in this state, the existence of the head of a sound recording part of the tape is detected. When a program is approximately searched as the result, a cam gear 6 is rotated counterclockwise and moved to the reverse play position. In this position, a part 3b to be controlled of a switching arm 3 pressed to an engaging roll 6b of the cam gear 6 in the fast forwarding position is released, and the switching arm 3 is energized counterclockwise by the energizing force of a tension spring 5, and the brake 2 is pressed by a pressing part 3c. In this case, the strong energizing force as the sum of energizing forces of the preload spring 4 and the tension spring 5 is applied to the brake 2 to apply the sufficient back tension to the tape.

Description

[Detailed Description of the Invention] [Industrial Application Field] The present invention relates to a magnetic recording/reproducing device using a tape as a recording medium, and particularly relates to a brake mechanism for applying a load to a rotating reel base. Related.

[Prior Art] In a magnetic recording/reproducing device using tape as a recording medium,
In order to keep the tape in contact with the head with constant pressure during play and to ensure stable tape running, it is necessary to prevent excessive force from being applied to the tape or from loosening it. For this purpose, a tension brake is provided near the reel base to apply an appropriate load to the reel base on the supply side and apply back tension to the tape during play.

In addition, when winding quickly, the reel base on the take-up side rotates at high speed, so the rotational moment applied to the reel base on the supply side through the tape also increases.
If the resistance to rotation of the reel base on the supply side is small, the reel base on the supply side will run faster than necessary, and the amount of tape fed will be greater than the amount of tape taken up by the reel base on the take-up side, causing the tape to become slack. , which may interfere with subsequent tape operations. In order to prevent such problems, a preload brake is installed near the reel base, which applies an appropriate load to the reel base on the supply side during fast winding to reduce the amount of rotation of the reel base on the supply side. is controlled.

By the way, one of such magnetic recording and reproducing devices is D.
Conventionally, in AT, tape play is performed only in one direction of travel (hereinafter referred to as forward play), so in this forward play, only the reel base on the supply side (hereinafter referred to as reverse side reel base) A tension brake is provided and configured to apply pack tension. As a tension brake for such a reverse side reel base, a band brake is usually used that tightens or loosens the outer circumference of the reel base using a band placed around the reel base. It is configured to add pack tension.

Furthermore, in DAT, since fast winding is performed in both running directions, preload brakes are provided on both reel bases. As such a preload brake, a type of brake that presses the pad against the reel base is used, and specifically, a 2.5gc brake is used.
It is configured to apply pack tension of about m.

As mentioned above, conventional DATs were configured to have a tension brake only on the reverse reel base to apply pack tension, but recently, with the development of high-speed cue search technology, the normal In addition to forward play, there is a need for tape play in the opposite running direction for cueing (hereinafter referred to as reverse play), and in this reverse play as well, the reel base (hereinafter referred to as forward side), which is the supply side, has become necessary. It is required to apply a load to the reel base (referred to as the reel base) and apply pack tension to the tape.

That is, in the high-speed cue search, the head of the audio recording section is detected by running at a speed 150 to 200 times faster than normal forward play, and after roughly cueing,
2. Normal forward play run to remove tape that has gone too far.
This is to search for the head by running it in reverse play at about 5x speed and to accurately locate the head. In reverse play to perform accurate cueing, extremely stable tape running is required, so the pinch roller is pressed against the capstan in the same way as in forward play, and the reel base on the supply side (forward side Apply a load similar to forward play to the reel base) and apply a load of 8 to 12 to the tape.
gcm of pack tension is required.

In response to such a request, a simple idea would be to provide the forward side reel base with a tension brake with the same configuration as the reverse side reel base, but a pinch roller would be installed around the forward side reel base. In most cases, the movement path and drive gear mechanism are installed in the space cup, so if a new tension brake is installed, additional brake release members may be required. It is inevitable that the equipment will become larger and more complex.

[Problems to be Solved by the Invention] The present invention has been proposed to solve the problems of the prior art as described above, and its purpose is to apply sufficient pack tension to the tape during reverse play and to maintain stability. To provide a compact and simple brake mechanism that enables high-precision, high-speed cue searching by running the tape in a controlled manner, and also contributes to the miniaturization and simplification of an apparatus. .

[Means for Solving the Problems] The brake mechanism according to the present invention focuses on the preload brake, which is an existing configuration, in the forward side reel base, and makes it possible to switch the biasing force applied to the preload brake, thereby converting this brake into a tension brake. It is also used as a.

That is, the present invention includes a reel base, a rotatably provided brake that presses against the reel base, and a first biasing means that biases the brake in a direction that presses the brake against the reel base.
a second urging means having a larger urging force than the first urging means and urging the brake in a direction to press the brake against the reel base; The present invention is characterized by comprising urging force switching means for separating the urging means from the brake, and control means for controlling the position of the urging force switching means according to the mode.

[Operation] In the present invention having the above configuration, during reverse play, the urging force of the second urging means or the first urging force is applied to the second urging means.
By applying a large biasing force to the biasing force of the biasing means, it is possible to press the brake against the reel base and apply sufficient pack tension to the tape. Therefore, stable tape running is possible, and highly accurate, high-speed cue searching becomes possible.

In addition, during fast winding, the control means rotates the urging force switching means, disconnects the second urging means, presses the brake against the reel base only by the small urging force of the first urging means, and presses the brake against the reel base. can perform stable high-speed rotation.

Furthermore, the brake mechanism of the present invention serves both as a preload brake during early winding and as a tension brake during reverse play, and a second urging means and urging force switching means are added to the configuration around the conventional preload brake. It is a small and simple mechanism that can be easily configured by simply adding it. Also,
It can be easily installed using the empty space of the conventional device configuration, and does not require a large new installation space, contributing to the miniaturization and simplification of the device.

[Example] An example of the brake mechanism according to the present invention will be specifically described below with reference to the drawings.

As shown in FIGS. 1 to 4, the brake mechanism of this embodiment includes a reel base 1, a brake 2, a switching arm (biasing force switching means) 3, a preload spring (first biasing means) 4, and a tension spring. Spring (second biasing means) 5,
It has a cam gear (control means) 6 and a brake release member 7, and the brake 2, the switching arm 3, and the brake release member 7 are rotatably provided on shafts 2a, 3a, and 7a, respectively.

That is, the brake 2 has a shaft 2a at one end,
A pad 2b that presses against the reel base l is provided at the outlet end of the rotation opening, and an engagement pin 2c that engages with the switching arm 3 is provided at the center thereof. The switching arm 3 has a shaft 3a in the center, a controlled portion 3b controlled by the cam gear 6 is provided at one end, and a suppressing portion 3c that presses the engagement pin 2C of the brake 2 is provided at the other end. is provided. Furthermore, near the axis 3a of this switching arm 3,
One end of the preload spring 4 and the tension spring 5 are each locked.

The other end of the preload spring 4 is locked to the brake 2, thereby urging the brake 2 in a direction (clockwise in the figure) to press the brake 2 into contact with the reel base 1. Further, the tension brake 5 has a larger biasing force than the preload spring 4, and its other end is locked to a fixing pin 8 fixed to the chassis of the device. The tension spring 5 biases the switching arm 3 counterclockwise in the figure, thereby indirectly applying the brake 2 to the reel base 1 via the engagement pin 2C of the pressing portion 3cs brake 2 of the switching arm 3. It is biased in the direction of pressure contact.

On the other hand, the cam gear 6 is driven by a drive motor (not shown) and moves from a stop position as shown in FIG. 1 to a forward play position as shown in FIG. 2, a fast winding position as shown in FIG. 3, a reverse play position as shown in FIG. The mode is rotated sequentially in a counterclockwise direction depending on the mode, and is held at a predetermined mode position. This cam gear 6 includes a cam 6a that controls other members (not shown), a switching arm 3, and a brake release member 7.
The engagement roller 6b rotates the switching arm 3 clockwise in the figure in the fast winding position shown in FIG. When the brake 2 is released from being suppressed by the biasing force and is in the forward play position as shown in FIG. 2, the brake release member 7 is rotated clockwise in the figure to release the brake 2.

Further, the brake release member 7 has a shaft 7a at the center, and has arms on three sides from this shaft. A controlled portion 7b controlled by the cam gear 6 is provided at the tip of one arm, and an engagement protrusion 7C that engages with the brake 2 is provided at the center of the other arm. The brake release member 7 is biased counterclockwise in the drawing by a spring (not shown), and assumes the initial position as shown in FIG. 1 when no other external force is applied.

The operation of this embodiment will be explained below.

■Storage position → Forward play position (Fig. 1 → 2nd
(Figure) First, in the stop position as shown in Figure 1, the switching arm 3 and the brake release member 7 are not controlled by the cam gear 6, so the biasing force of the tension spring 5 causes the switching arm 3 to move in the opposite direction as shown in the figure. biased clockwise,
The brake 2 is in pressure contact with the reel base 1 via the engagement pin 2C of the pressing portion 3cs brake 2 of the switching arm 3. In this case, the pressure contact force of the brake 2 is the sum of the biasing forces of the tension spring 5 and the preload spring 4.

When a play operation command is issued from the stop position shown in FIG. 1 and the drive motor starts, the cam gear 6 rotates counterclockwise and moves to the forward play position shown in FIG. 2, and the cam gear 6 is engaged. The roller 6b presses the controlled portion 7b of the brake release member 7 clockwise in the figure. As a result, the brake release member 7 rotates clockwise in the figure, and the engaging protrusion 7c rotates the brake 2 counterclockwise in the figure, thereby releasing the brake 2.

■Forward play 4 position → High speed cue search (Fig. 2 →
(Fig. 3→Fig. 4) When a high-speed cue search command is issued at the forward play position shown in Fig. 2, the cam gear 6 further rotates counterclockwise, resulting in fast winding as shown in Fig. 3. move to position,
The engagement roller 6b of the cam gear 6 releases the pressure on the controlled portion 7b of the brake release member 7, and instead presses the controlled portion 3b of the switching arm 3 clockwise in the figure. As a result, the brake release member 7 returns to its initial position by the biasing force of a spring (not shown), and the brake 2 becomes free.

Further, the switching arm 3 rotates clockwise in the figure due to the pressure of the engagement roller 6b, and the engagement protrusion 7c of the switching arm 3 separates from the brake 2. Therefore, the brake 2 is operated only by the biasing force of the preload spring 4. Press it against the reel base 1.

At such a fast winding position, high-speed running is performed at a speed 150 to 200 times faster than normal forward play running.

In this case, since a small biasing force of only the preload spring 4 is applied to the brake 2, stable high-speed running can be performed. Then, while the tape is running at high speed in this manner, a detection mechanism (not shown) detects the presence of the beginning of the audio recording section of the tape.

As a result, when the approximate cueing is performed, the cam gear 6 further rotates counterclockwise and moves to the reverse play position as shown in FIG. 4. In this position, the controlled portion 3b of the switching arm 3, which was pressed by the engagement roller 6b of the cam gear 6 in the fast winding position, is released from the suppression, so that the switching arm 3 is It is biased in the middle counterclockwise direction and presses the brake 2 by its suppressing portion 3C. In this case, the brake 2 includes a preload spring 4 and a tension spring 5.
A large biasing force is added, which is the sum of the biasing forces of both.

At such a reverse play position, reverse play running is performed at a speed 2.5 times faster than normal forward play running. In this case, a large biasing force is applied to the brake 2, which is the sum of the biasing forces of the preload spring 4 and the tension spring 5. Therefore, sufficient pack tension can be applied to the tape, making it possible to perform stable play running. It is possible to find the beginning of the tape that has gone too far during the previous high-speed run and perform accurate cueing.

Furthermore, since the brake mechanism of this embodiment serves both as a preload brake for fast winding and as a tension brake for reverse play, the number of parts is small and the structure is excellent in compactness and simplification. That is, this embodiment uses the existing preload brake mechanism configuration of the brake 2, preload spring 4, cam gear 6, and brake release member 7 as is, and simply adds the tension spring 5 and the switching arm 3. It can be configured as follows. In this case, as can be seen from the drawings, the switching arm 3 may be provided overlapping the brake 2, and the tension spring 5 can also be easily installed by utilizing the empty space. Therefore, compared to the case where a dedicated tension brake is newly provided, the structure can be made smaller and simpler with fewer parts, which can greatly contribute to making the entire device smaller and simpler.

It should be noted that the present invention is not limited to the above-mentioned embodiments. For example, the present invention may be configured such that only the biasing force of the tension spring is applied to the brake during reverse play, that is, either of the first and second biasing means may be used. A configuration in which only one of the two members is selected to switch the biasing force is also possible, and the shape of each member can be freely selected.

[Effects of the Invention] As explained above, according to the present invention, by making it possible to switch the biasing force applied to the brake and using this brake as both a preload brake and a tension brake, sufficient pack tension can be applied to the tape during reverse play. With the addition of
Furthermore, it is possible to provide a compact and simple brake mechanism that contributes to the miniaturization and simplification of the device.

[Brief explanation of the drawing]

1 to 4 are plan views showing one embodiment of the brake mechanism according to the present invention, in which FIG. 1 is in a stopped state, FIG. 2 is in a forward play state, FIG. 3 is in a fast winding state, and FIG. 4 is in a fast winding state. indicates the reverse play state. 1... Reel base, 2... Brake, 2a, 3a
. 7a... Shaft, 2b... Pad, 2c... Engagement pin, 3... Switching arm, 3b... Controlled part, 3c...
- Pressing part, 4... Preload spring, 5... Tension spring, 6... Cam gear, 6a... Cam, 6b... Engagement roller, 7... Brake release member, 7b... Controlled part, 7c... Engaging protrusion, 8...
Fixed pin.

Claims (1)

[Scope of Claims] A reel base, a rotatably provided brake that presses against the reel base, and a first brake that biases the brake in a direction that presses the brake against the reel base.
a second biasing means having a larger biasing force than the first biasing means and biasing the brake in a direction to press the brake against the reel base; A brake mechanism comprising: urging force switching means that separates the second urging means from the brake by operation; and control means that controls the position of the urging force switching means according to a mode.