JPH08297888A - Pinch roller assembly of tape recorder - Google Patents

Abstract

PURPOSE: To incline a rotation part within a predetermined range instead of a simple structure by a method wherein a plastic journal bearing etc., is provided in place of a ball bearing. CONSTITUTION: A pinch roller assembly 30 is provided on a support arm 27, comprising a support shaft 21 of the assembly, a plastic journal bearing of sliding bearing means 22, a cushion member 23, and cylindrical rotation parts 24, 25, 26. The sliding bearing means 22 are rotatably supported with respect to the support shaft 21 having a small diameter part 21a and a large diameter part 21b different from each other, and comes into sliding contact with each other. Further, the sliding bearing means 22 have a groove 28 along the outer circumferential face, and the cushion member 23 of much softer rubber than the roller 24 of high elastic rubber is engaged with this groove 28, and the cylindrical rotation parts 24, 25, 26 can be inclined with respect to the support shaft 21.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pinch roller for a tape recorder, and more particularly to a pinch roller assembly provided to press a running tape against a capstan shaft to stabilize the running of the tape.

[0002]

2. Description of the Related Art A conventional tape recorder has a pinch roller assembly on a deck for running the tape in a more stable state. In such a pinch roller assembly, normally, the running tape is pressed so as to be pressed against the capstan shaft so that the running tape has a constant speed and tension.

FIG. 1 is a schematic plan view showing a deck 10 of a conventional tape recorder. The tape T runs from the supply reel 1 provided on the deck 10 to the take-up reel 2 via the erasing head 3, the rotary head drum 4, and the capstan shaft 5.

The pinch roller 6 is constructed so as to be movable in the direction of the arrow, and is located away from the capstan shaft 5 when the tape T is fast forwarded or rewound.
When the tape recorder is in the reproduction or recording mode, the running tape T is pressed toward the capstan shaft 5 as shown in the figure. As a result, the tape T runs with a predetermined tension by the rotation and frictional force of the capstan shaft 5 driven by a capstan motor (not shown) and the pinch roller 6 whose outer peripheral surface is made of an elastic body such as rubber. Therefore, the running tape T can always be brought into contact with the head drum in a stable state.

On the other hand, in order for the pinch roller 6 and the capstan shaft 5 to function normally as described above, the outer peripheral surface of the pinch roller 6 and the capstan shaft 5 contact each other with a uniform force in the vertical direction. This is very important. However, due to elastic deformation of the capstan shaft 5 and the pinch roller 6, or manufacturing and assembling errors of the shaft, it is difficult to make the capstan shaft 5 and the pinch roller 6 parallel to each other. A state where the outer peripheral surface of 6 partially contacts is generated. In this case, the tape T interposed between the two members 5 and 6 deviates from the original running height and rises or descends, or the surface is damaged, resulting in an unsatisfactory result. There is.

In order to prevent such partial contact, the conventional pinch roller assembly generally uses a ball bearing between the rotating portion of the pinch roller and the support shaft. FIG. 2 shows a conventional pinch roller assembly 20 having a ball bearing structure 11 and a capstan shaft 5.
And are shown. Due to the structure of the ball bearing structure 11, the ball 11b is provided between the inner ring 11a and the ball 11b.
And a gap (not shown) between the outer ring 11c and
As a result, the rotating portion 13 of the pinch roller can be inclined at a predetermined angle α'with respect to the axial direction. Therefore, even when the pinch roller shaft 12 and the capstan shaft 5 are not parallel to each other, the rotation part 13 of the pinch roller is tilted at a predetermined angle, so that the capstan shaft and the outer peripheral surface of the pinch roller are appropriately arranged. And can be evenly contacted.
However, the ball bearing used in such a method has a drawback that the cost is high and the pinch roller is a small-sized component, and therefore it is very difficult to manufacture.

As another method for preventing the above-mentioned partial contact, Japanese Utility Model Publication No. 1-1.
No. 74731 shows a pinch roller structure in which an annular bearing is interposed between a rotating portion of the pinch roller and a support shaft. In addition, Japanese Utility Model Publication No. Hei 1-177437.
No. 1-17743 discloses a structure in which a spherical projecting portion made of a magnetic material is interposed between a rotating portion and a support shaft.
No. 6 shows a pinch roller structure having a support shaft having a groove having a semicircular cross section on the outer peripheral surface, and a cylindrical rotating portion having a protrusion fitted on the groove formed on the inner peripheral surface. However, it is not only very difficult to process the annular bearing, the spherical projection, the groove having a semicircular cross section, etc., which are adopted by the above-mentioned conventional pinch rollers, etc. Due to its structure, it is not easy to assemble by interposing the above-mentioned members inside.

[0008]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned conventional problems, and its rotating portion can be tilted within a predetermined range, and the structure is simple and the production cost is low. It is an object of the present invention to provide a less expensive pinch roller assembly for a tape recorder.

[0009]

SUMMARY OF THE INVENTION An object of the present invention is to provide a tape recorder having a support shaft which is provided on a support arm and has a step-shaped portion in the middle thereof, and a support shaft which is rotatable to the step-shaped portion. A sliding bearing means located at, and a cushion member fixed to the outer peripheral surface of the sliding bearing means,
A pair of cylindrical bushing members for fixing the cushion member, a sleeve closely fixed to the outer peripheral surface of the cushion member, and a cylindrical rubber closely contacted to the outer peripheral surface of the sleeve. This is accomplished by providing a pinch roller assembly.

Further, according to the present invention, as one embodiment, the sliding bearing means is a plastic journal bearing.

As another embodiment, the present invention is characterized in that the sliding bearing means is a metal sliding bearing.

[0012]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT A preferred embodiment of a pinch roller assembly for a tape recorder according to the present invention will be described in more detail with reference to the drawings.

FIG. 3 is a side sectional view showing an embodiment of the pinch roller assembly according to the present invention. The pinch roller assembly 30 according to the present invention is roughly composed of a support shaft 21, a sliding bearing means 22, a cushion member 23, and cylindrical rotating portions 24, 25, 26 of the assembly. The cylindrical rotating parts 24, 25, and 26 are a pair of rollers 24 made of a highly elastic material such as rubber, a metal sleeve 25 press-fitted inside the roller 24, and a pair of cushion members 23 for fixing positions. Bushing members 26a and 26b are included.

Support shaft 21 provided on support arm 27
Is composed of a small diameter portion 21a and a large diameter portion 21b having different diameters. The stepped portion, which is the boundary between these two parts, serves as a support surface for the sliding bearing means 22.

The sliding bearing means 22 is rotatably supported by the stepped portion with respect to the support shaft 21, and the sliding bearing means 22 and the support shaft 21 slidably contact each other. The sliding bearing means 22 is preferably a plastic journal bearing manufactured by injection molding plastic with a bearing structure.

On the other hand, the sliding bearing means 22 has a groove 28 along its outer peripheral surface, and a cushion member 23 is fitted in the groove 28. The cushion member 23 allows the cylindrical rotating portions 24, 25 and 26 to be inclined with respect to the support shaft 21, and it is preferable to use rubber that is softer than the roller 24.

In order to prevent the sliding bearing means 22 from vertically shifting along the support shaft 21, the fixed cap 2
It is also possible to press-fit and fix 9 to the upper end of the small diameter portion 21a.

FIG. 4 shows a second embodiment of the present invention in which a metal sliding bearing is used as the sliding bearing means 31. The metal sliding bearing has an advantage that, when lubricating oil is used, an oil film formed between the metal sliding bearing and the support shaft 32 facilitates the rotation of the cylindrical rotating portions 24, 25, and 26 with respect to the support shaft 32.

[0019]

According to the pinch roller assembly of the present invention as described above, a plastic journal bearing or a metal sliding bearing injection-molded from synthetic resin can be used without using an expensive ball bearing.
There is an advantage that the pinch roller can be rotatably supported by the pinch roller support shaft and the unit price can be reduced.

In the pinch roller assembly of the present invention, the cushion member used for preventing partial contact between the capstan shaft and the cylindrical rotating portion of the pinch roller is manufactured according to a standard such as size at the time of manufacture. Since it does not require high accuracy, it is easy to process, and the simple structure makes the pinch roller assembly work easier.

[Brief description of drawings]

FIG. 1 is a schematic plan view showing a deck of a tape recorder.

FIG. 2 is a side sectional view showing a capstan shaft and a pinch roller assembly of a conventional tape recorder.

FIG. 3 is a first embodiment of a pinch roller assembly of a tape recorder according to the present invention.

FIG. 4 is a second embodiment of the pinch roller assembly of the tape recorder according to the present invention.

[Explanation of symbols]

 1 Supply reel 3 Erasing head 4 Rotating head drum 5 Capstan shaft 2 Take-up reel 6 Pinch roller 10 Deck T 11 Ball bearing structure 11a Inner ring 11b Ball 11c Outer ring 12 Pinch roller shaft 13 Pinch roller rotating part 20 Conventional pinch roller Assembly 21 Support shaft 21a Small diameter part of the support shaft 21b Large diameter part of the support shaft 21 Sliding bearing means 23 Cushion member 24 Roller 25 Metal material sleeve 26a Bushing member 26b Bushing member 27 Support arm 28 Groove 29 Fixed cap 30 Pinch roller assembly according to the present invention T tape α'predetermined angle with respect to axial direction

Claims (3)

[Claims] 1. In a tape recorder, a support shaft provided on a support arm and having a step-shaped portion in the middle, a slide bearing means rotatably positioned in the step-shaped portion of the support shaft, and the slide bearing. A cushion member fixed to the outer peripheral surface of the means, a pair of cylindrical bushing members for fixing the cushion member, a sleeve closely fixed to the outer peripheral surface of the cushion member, and a close contact to the outer peripheral surface of the sleeve. And a cylindrical rubber. 2. The pinch roller assembly of the tape recorder according to claim 1, wherein the sliding bearing means is a plastic journal bearing. 3. The pinch roller assembly of the tape recorder according to claim 1, wherein the sliding bearing means is a metal sliding bearing.