JPH07311999A - Reel brake - Google Patents

Abstract

PURPOSE:To guarantee brake damping capacity and at the same time use a brake properly for a long time. CONSTITUTION:Two posts 52 and 53 which are aligned side by side with a space in peripheral direction are provided around a reel stand 36 and retention pieces 54 and 55 for enabling a brake shoe holder 48 to be placed are provided at the posts 52 and 53. Therefore, the inclination of the brake shoe holder 49 can be suppressed for the plane in diameter direction of the reel stand 36 by the retention pieces 54 and 55, thus preventing a brake shoe holder 48 from being inclined greatly and fully adhering the brake shoes 51 and 52 to a brake drum 37 when damping with a brake. Also, the contact of the brake shoes 51 and 52 to the brake drum 37 can be prevented when the reel stand 36 rotates to suppress wear.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reel brake device suitable for application to a magnetic recording / reproducing device such as a video tape recorder.

[0002]

2. Description of the Related Art Recently, video tape recorders (hereinafter referred to as
It is called "VTR". The magnetic recording / reproducing apparatus such as), etc. has been remarkably widespread, and the VTR has become familiar with it.

Conventionally, as this type of VTR, one provided with a tape loading device as shown in FIG. 4, for example, has been adopted.

This will be described in brief with reference to FIG. 1. In FIG. 1, the reference numeral 1 indicates a lead (not shown) provided in the tape traveling system R for guiding the magnetic tape T on the outer peripheral surface of the drum. The head drums 2 and 3 that are provided are movably provided on the tape supply side and the tape winding side of the head drum 1, and the magnetic tape T in the tape cassette 4 is pressed against the leads (not shown) to the drum outer peripheral surface. Inclination guides 2a and 3a for winding and vertical guides 2b,
3 is a two guide assembly with 3b.

Reference numeral 5 is a tape cleaner, 6 is a capstan, 7 is a pinch roller, 8 is a full erase head, and 9 is a full erase head.
Is a channel erase head, 10 is an audio recording / reproducing head, 11 is a control confidence head, 12 is a tape pull-out guide on the supply side, 13 is a tape pull-out guide on the winding side, 14 is a tension detector, and 15 and 16 are tapes on the feed side. Tape guides 17 to 19 are winding side tape guides, 20 is a supply side reel, 21 is a winding side reel, and 22 is a rotary head.

Reference numeral 23 indicates the head rotation direction of the head drum 1, 24 indicates the tape running direction during recording / reproducing and fast-forwarding, and 25 indicates the tape running direction during rewinding.

In addition, arrows a to d in the figure show movement trajectories of the guide assemblies 2 and 3 and the tape pull-out guides 11 and 12 at the time of tape loading.

In addition, the VTR has a brake drum (not shown) on its outer peripheral surface, and a reel stand (not shown) on which the reels 20 and 21 can be placed when the tape cassette is mounted, and these reel stands. A reel brake device (not shown) having a reel brake (not shown) for braking / releasing (not shown) is built in.

Of these, the reel brake of the reel brake device is provided with a brake shoe holder composed of a rotating member for holding a brake shoe that can be pressed into contact with the outer peripheral surface of the brake drum.

The tape loading of the tape loading device constructed as described above is performed by moving the guide assemblies 2, 3 and the tape pull-out guides 12, 13 from the cassette mounting position to the drum side.

That is, the guide assembly 2 on the supply side and the guide assembly 3 on the winding side, which move in opposite directions with the head drum 1 interposed therebetween, pull out the magnetic tape T in the tape cassette 4 to cause the head drum 1 to move. Wrap it around the outer surface in a spiral shape.

Further, the tape pull-out guide 12 on the supply side
The tape pull-out guide 13 on the take-up side is a head group such as the capstan 6, the full erase head 8, the tape guides 15 and 16 on the supply side, and the tape guide 17 on the take-up side.
Wrap around ~ 19.

In the recording / reproducing mode, the pinch roller 7 presses the magnetic tape T against the capstan 6 and
When the reel 21 on the winding side is rotationally driven to wind up the magnetic tape T, recording / reproduction is performed by the rotary head 22 of the head drum 1.

On the other hand, in order to brake the reel stand by the reel brake device, the brake shoe is brought into pressure contact with the outer peripheral surface of the drum of the brake drum, and in order to release the brake of the reel stand, the brake shoe is attached to the outer peripheral surface of the drum of the brake drum. It is performed by separating from.

By the way, in this type of VTR, an FG ring for detecting the number of revolutions may be integrated with the reel base due to the restriction of the internal space.
Often the G ring is also used as the brake drum.

[0016]

However, the conventional VT
The reel brake device of R does not have a function of positioning the brake shoe holder, so that the brake shoe holder may tilt excessively with respect to the radial plane of the reel stand.

That is, the brake shoe holder is held at the pivotal fulcrum, but the component assembly accuracy at this pivotal fulcrum is set to a relatively low component assembly accuracy because it is necessary to reduce the assembly cost. Because it is.

As a result, there is a problem that the brake shoe does not sufficiently come into close contact with the brake drum at the time of brake braking, and the braking ability cannot be guaranteed.

Further, excessive tilting of the brake shoe holder with respect to the radial plane of the reel stand makes it easier for the shoe end of the brake shoe to come into contact with the brake drum when the reel stand rotates, and the brake shoe wears. There was a problem that it could not function as a brake for a long time.

The present invention has been made in view of the above circumstances, and provides a reel brake device which can guarantee the braking ability and can function as a brake for a long period of time. .

[0021]

In the reel brake device according to the present invention, two columns are provided around the reel base and are arranged in parallel with each other at intervals in the circumferential direction, and a brake shoe holder can be mounted on each column. The holding piece is provided.

[0022]

In the present invention, the two holding pieces prevent the brake shoe holder from tilting with respect to the radial plane of the reel stand.

[0023]

Embodiments of the present invention will be described in detail below with reference to embodiments shown in the drawings.

FIGS. 1A and 1B are plan views showing a brake braking state and a brake braking released state of the reel brake device according to the present invention, and FIG. 2 is a holding of a brake shoe holder of the reel brake device according to the present invention. FIG. 3 is a side view showing a contact state with one piece, and FIG. 3 is a sectional view showing a positional relationship among the reel brake device, the reel stand and the tape cassette in the present invention.

In the figure, reference numeral 31 denotes a cassette housing having an opening 31a for inserting a reel stand, which is formed by a rectangular box composed of two upper and lower halves 32 and 33 fitted to each other. There is.

Reference numeral 34 designates two tape reels, each of which is arranged in parallel with each other in the left-right direction at a predetermined interval (only one is shown).
The reel hub 34a, which has the recess 35 for inserting the reel base, and on which the magnetic tape T can be wound, and the reel hubs 34
It is composed of an upper reel flange 34b and a lower reel flange 34c, which are provided at the upper and lower ends of a and face each other, and are rotatably provided in the cassette housing 1.

Reference numeral 36 denotes two reel stands (only one is shown) which are arranged in parallel in the left-right direction at a predetermined interval.
When the tape cassette is attached to the reel base block 3 that can be fitted into the recess 35 by being inserted through the opening 31a.
6a and a reel base flange 36b integrally provided on the reel base block 36a and having a brake drum 37 on its outer peripheral surface, and are rotatably mounted on a VTR chassis 38.

Reference numeral 39 denotes a first brake arm having a substantially L-shape in plan view, which is a cylindrical body 40 for vertically inserting a pin and a parallel body provided integrally with the cylindrical body 40 at a predetermined interval in the longitudinal direction. A long arm piece 41 having a plurality of spring locking holes 41a and 41b, and a long arm piece 41 which is continuously provided at one end of the long arm piece 41 and projects in a direction perpendicular to the parallel direction of the spring locking holes 41a and 41b. It is composed of a short arm piece 42, and the arm corner portion has a pivot pin 43 on the chassis 38.
It is rotatably provided via.

A rotating force in the braking direction is applied to the first brake arm 39 by the first tension coil spring 44, and a rotating force in the braking release direction is applied by an electromagnetic solenoid (not shown). .

The long arm piece 4 of the both spring locking holes 41a and 41b of the first brake arm 39 is used.
One end of the first tension coil spring 44 is locked in the spring locking hole 41a near the tip of the first coil spring 1.

Reference numeral 45 denotes a second brake arm having an I-shape in plan view, and an arm intermediate portion is rotatably provided at a tip end portion of the short arm piece 42 via a pivot support pin 46, and one end of one end of the arm is provided. A through hole 47 having a plurality of spring locking grooves 47a corresponding to the spring locking holes 41b on the central portion side of the long arm piece 41 among the spring locking holes 41a and 41b is provided in the portion.

Reference numeral 48 is a second tension coil spring for applying a turning force to the second brake arm 45 in the braking direction, and each spring end has the spring locking groove 47.
a and the spring locking hole 41b.

Reference numeral 49 denotes a brake shoe holder for holding a shoe, which comprises a holder base portion 49a having a substantially triangular shape in plan view and a shoe holding portion 49b having a U-shaped cross section.
The pivot pin 5 is provided at the other end of the brake arm 45.
It is provided rotatably through 0.

Two brake shoes 51 and 52 are arranged in parallel with each other at a predetermined interval in the circumferential direction. The two brake shoes are mounted on the shoe holding portion 49b of the brake shoe holder 49, and the brake is provided at the end portion on the reel stand side. An arc surface 5 that can be pressed into contact with the outer peripheral surface 37a of the drum 37
1a and 52a are formed.

Reference numerals 53 and 54 denote two columns, which are arranged in parallel with each other in the circumferential direction at intervals, and are erected around the reel base 36 and fixed to the upper surface of the chassis 38.

55 and 56 are the shoe holding portions 49b.
Are provided at the lower ends of the columns 53 and 54 and extend in the radial direction of the reel stand 36 and can guide the brake shoe holder 49. Is configured.

Reference numeral 57 is a spring locking hole provided in the chassis 38 for locking the other end of the first tension coil spring 44.

In the reel brake device thus constructed, in order to brake the rotating reel stand 36, the circular arc surfaces 51a and 52a of the brake shoes 51 and 52 are pressed into contact with the drum outer peripheral surface 37a of the brake drum 37. It is carried out by

At this time, the first tension coil spring 44
The first brake arm 39 is pivotally supported by the pivot pin 4
3 is rotated counterclockwise as shown in FIG.
Following the rotation of the first brake arm 39,
The brake arm 45 is displaced in a direction of approaching the reel stand 36, and the displacement of the second brake arm 45 causes the brake shoe holder 49 to be guided and held on the holding pieces 55 and 56, while the drum outer peripheral surface 37a of the brake drum 37 is being held.
Displace in the circumferential direction and the radial direction.

On the other hand, to release the braking of the reel base 36,
This is performed by separating the arcuate surfaces 51a, 52a of the brake shoes 51, 52 from the drum outer peripheral surface 37a of the brake drum 37.

At this time, the first brake arm 39 resists the repulsive force of the first tension coil spring 44 by the driving force of the electromagnetic solenoid (not shown), and the pivot pin 43 serves as the center as shown in FIG. The second brake arm 45 is rotated in the clockwise direction as shown, and is displaced in the direction in which the second brake arm 45 is separated from the reel base 36 following the rotation operation of the first brake arm 39. The displacement of the second brake arm 45 causes the brake shoe to move. While the holder 49 is guided and held on the holding pieces 55 and 56, the holder 49 is displaced in the circumferential direction and the radial direction away from the drum outer peripheral surface 37a of the brake drum 37.

Therefore, in this embodiment, since the two holding pieces 55 and 56 can suppress the tilting of the brake shoe holder 49 with respect to the radial plane of the reel stand 36, the brake shoe holder 49 can be replaced as in the conventional case. The brake shoes 51 and 52 can be sufficiently brought into close contact with the drum outer peripheral surface 37a of the brake drum 37 without being largely tilted.

Further, in this embodiment, the holding pieces 54,
Since the tilt of the brake shoe holder 49 with respect to the radial plane of the reel stand 36 can be suppressed by 55, contact of the brake shoes 51, 52 with the brake drum 37 can be prevented when the reel stand 36 rotates. The wear of the brake shoes 51, 52 can be suppressed.

Further, in the present embodiment, the wear of the brake shoes 51, 52 can be suppressed, and the degree of freedom in selecting the material of the brake shoes 51, 52 can be increased, so that the material cost can be reduced.

Besides, in the present embodiment, the holding pieces 54,
Since the tilting of the brake shoe holder 49 can be suppressed by 55, the assembling accuracy of the parts can be relaxed, so that the assembling cost can be reduced.

In the present embodiment, the example applied to the VTR is shown, but the present invention is not limited to this, and can be applied to other magnetic recording / reproducing devices as in the embodiment. .

[0047]

As described above, according to the present invention, two columns, each of which is arranged in parallel with each other at intervals in the circumferential direction, are provided around the reel stand, and the brake shoe holder can be mounted on each of these columns. Since the piece is provided, the holding piece suppresses the tilting of the brake shoe holder with respect to the radial plane of the reel stand.

Therefore, unlike the conventional case, the brake shoe holder does not largely tilt, so that the brake shoe can be sufficiently brought into close contact with the brake drum, and the braking ability can be guaranteed.

Further, since the tilting of the brake shoe holder with respect to the radial plane of the reel stand can be suppressed by the holding piece, it is possible to prevent the brake shoe from contacting the brake drum when the reel stand rotates. Wear can be suppressed, and it can function as a brake for a long period of time.

[Brief description of drawings]

1A and 1B are plan views showing a brake braking state and a brake braking released state of a reel brake device according to the present invention.

FIG. 2 is a side view showing a contact state between the brake shoe holder and the holding piece of the reel brake device according to the present invention.

FIG. 3 is a cross-sectional view showing a positional relationship among a reel brake device, a reel stand and a tape cassette according to the present invention.

FIG. 4 is a plan view showing a tape running system of the video tape recorder.

[Explanation of symbols]

 31 ... Cassette housing 34 ... Tape reel 36 ... Reel stand 37 ... Brake drum 37a ... Drum outer peripheral surface 38 ... Chassis 39 ... First brake arm 45 ... Second brake arm 49 ... Brake shoe holder 51, 52 ... Brake shoe 51a, 52a ... Arc surface 53, 54 ... Struts 55, 56 ... Holding piece T ... Magnetic tape

Claims (2)

[Claims] 1. A reel brake device comprising a brake shoe holder that holds a brake shoe that is rotatably supported at a radial position on a reel stand and is capable of pressing contact with a brake drum. Providing two columns that are parallel to each other at intervals in the circumferential direction,
A reel brake device characterized in that a holding piece capable of mounting the brake shoe holder is provided on each of these columns. 2. A reel brake device, wherein the holding piece is constituted by a guide piece extending in a radial direction of the reel stand.