JPS6336520Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION (Industrial Field of Application) The present invention relates to a guide roller for transporting a strip of material such as a magnetic tape used, for example, in a video tape recorder.

(Prior Art) In devices that use magnetic tape, such as video tape recorders, one or more guide rollers are used to guide the magnetic tape to be played back or recorded to a head or to a cassette. It is provided.

By the way, unlike drive rollers such as pinch rollers, this type of guide roller is a roller that simply guides the transport of the magnetic tape, and rotates only by friction with the magnetic tape, so the rotational friction The resistance is required to have an extremely small value, and in particular, in the case of guide rollers used in video tape recorders, the rotational state of the rollers affects the image, so the rotational precision must be high.

This type of guide roller uses a bearing as a rotating member, and the clearance of the bearing portion is adjusted during assembly in order to reduce rotational frictional resistance and improve rotational accuracy.

Conventionally, methods for adjusting the clearance of the bearing section include a screw type fixing with a double nut, or a press-fitting method or adhesive method without using screws.

However, in the case of the former screw type, it is extremely difficult to maintain the ideal perpendicularity or parallelism to the reference plane when threading a single part, and moreover, in the case of the screw type, it is extremely difficult to maintain ideal perpendicularity or parallelism to the reference plane. The disadvantage is that the reference surface (bearing receiving surface) where processing errors are collected cannot maintain ideal perpendicularity or parallelism.

In addition, in the latter case of press-fitting or gluing, it is difficult to finely adjust the clearance of the bearing part.
In practice, there are disadvantages in that excessive play occurs, making the shaft center unstable and reducing rotational accuracy.

(Purpose of the invention) The present invention was proposed in view of the above points, and its purpose is to be able to process each part with high precision, and to be able to easily assemble the parts while maintaining accuracy. To provide a guide roller in which the clearance of a bearing part can be easily finely adjusted during assembly.

That is, in order to achieve the above object, in the present invention, the clearance adjustment member attached to the support shaft is made relatively simple and can be machined with high precision, and is easily moved forward and backward in the axial direction of the support shaft. The clearance can be adjusted accordingly.

(Structure of the idea) The present invention will be explained below with reference to the drawings.

Figures 1A and 1B show a first embodiment of the guide roller according to the present invention. In the figure, 1 is a round bar-shaped support shaft, and the lower end side is a support frame built into a video tape recorder etc. (not shown) shall be supported as appropriate. Reference numeral 2 denotes a support portion that is provided on a mounting portion of a support frame or the like by fixing means such as screwing or crimping, and the support shaft 1 is press-fitted and fixed into a hole formed through the center of the support portion. Further, a substantially disc-shaped roller support part 2a extending outward is formed in this support part 2, and a ring-shaped roller guide groove 2b is formed on the upper surface of this roller support part 2a.
A ring-shaped rotating support part 3 made of a wear-resistant material is provided at the outer periphery of the hole on the upper surface of the roller support part. In this case, the ring rotation support part 3 can also be formed integrally with the support part 2.

Reference numeral 4 denotes a clearance adjustment part attached to the upper end of the support shaft 1. The clearance adjustment part 4 has a concave bearing support part 5a formed on the inside, and is very lightly press-fitted into the upper end of the support shaft 1 in the center. A rotary support part 5 is formed with a through hole 5b for insertion, and a rotary support part 5 is integrally connected to the rotary support part 5 and formed at the upper end of the support shaft through a screw hole 6a formed in the center. The cap 6 is screwed onto the threaded portion 1a.

That is, the rotary support part 5 has a body part 5 whose diameter is slightly smaller than the protruding part 5c that slightly protrudes downward.
d, and a threaded portion 5e is formed on the outer periphery of this body portion 5d. On the other hand, the cap 6 has an outer cylindrical part 6b, and is designed to receive a body part 5d in this outer cylindrical part 6b, and the inner circumferential wall of the outer cylindrical part 6b corresponds to the threaded part 5e on the outer periphery of the body. A threaded portion 6d is formed to connect the cap 6 through these threaded portions 5e and 6d.
and the rotation support part 5 are integrally connected to each other. Note that a recess 6e is formed at the top of the cap 6 into which a jig for attachment and detachment is inserted. The screw hole 6a formed at the center of the bottom of the cap 6 has a diameter corresponding to the screw portion 1a, which is smaller in diameter than the diameter of the support shaft body.

A cylindrical roller 7 is rotatably provided between the rotary support section 5 and the support section 2 for guiding a band-shaped object such as a tape. That is,
The lower end surface 7a of the roller 7 is disposed to face the groove 2b of the roller support portion 2a with a gap therebetween, and
The upper end surface 7b of the roller 7 is the protrusion 5 of the rotation support part 5.
It is arranged to face the lower surface 5f of c through a gap.
In this case, a concave stepped portion 7c is formed on the outer peripheral portion of the lower end of the roller, and this stepped portion 7c is arranged to face the corner portion 2b' of the outer peripheral wall of the groove 2b. Further, the outer peripheral wall of a collar 8 is fixed to the inner peripheral wall of the roller 7, and has rotary support surfaces 8a and 8b consisting of tapered surfaces at both ends thereof, and is rotatably provided around the support shaft 1. Support part 5 and ring rotation support part 3
A plurality of bearings 9, 10 are provided between the inner surfaces 5g, 3a and the circumferential surface of the support shaft 1 in the vicinity of the surfaces 5g, 3a, and the rotational support surfaces 8b, 8a of the collar 8 corresponding to these circumferential surfaces. is inserted in a ring shape, and a roller 7 is rotatably supported on the outer circumference of the support shaft 1 via bearings 9 and 10.

Next, an example of the procedure for assembling the guide roller of the present invention will be explained. First, the support portion 2 and the ring-shaped rotation support portion 3 are press-fitted and fixed at predetermined positions slightly below the center of the support shaft 1. It goes without saying that when the ring-shaped rotation support part 3 is integrally configured with the support part 2, the attachment of the ring-shaped rotation support part 3 is omitted.

Next, a collar 8 and a roller 7 are attached to the outer periphery of the support shaft 1 above the support portion 2 so as to be rotatable with respect to the support shaft 1. In this case, the collar 8 and the roller 7 are integrally connected by pressing the collar 8 into the roller 7 or using an adhesive or the like. The collar 8 and the roller 7 are rotatable by a plurality of bearings 9 provided between the rotation support surface 8a below the collar 8, the support shaft peripheral surface, and the inner surface 3a of the ring-shaped rotation support part 3. It is supported.

After that, a plurality of bearings 10 are provided between the rotation support surface 8b above the collar 8 and the corresponding support shaft peripheral surface, and a clearance adjustment part 4 is installed above the support shaft 1 to adjust the clearance. Just go.

That is, a cap 6 is attached around the body 5d of the rotation support part 5, and the two are integrated to form the clearance adjustment part 4 , and a through hole 5 is formed in the upper end of the support shaft 1.
The clearance adjustment part 4 can be easily attached to the support shaft 1 by screwing the clearance adjustment part 4 into the threaded part 1a at the upper end of the support shaft 1 through the screw hole 6a while inserting the 1, the clearance of the bearing portion can be easily adjusted or finely adjusted by moving the clearance adjustment section 4 forward or backward as appropriate. Then, if the clearance adjustment is appropriate, each member can be reliably connected to each other by bonding the top of the support shaft 1 and the cap 6 with adhesive.

In this way, in the present invention, since the structure of the rotation support member such as the clearance adjustment part 4 is relatively simple, it can be processed with high precision at the manufacturing stage. When installing, it can be easily installed without applying excessive force, so machining accuracy will not be compromised.

FIG. 2 shows a second embodiment of the present invention. In this example, the clearance adjustment section 4 is made of a single member, and the cap 6 and rotation support section 5 shown in FIG. 1 are integrally formed, reducing the number of parts. It differs from the previous embodiment in that it is reduced.

Further, FIG. 3 shows a third embodiment of the present invention, which differs from the first embodiment in that the protrusion 5c' of the rotation support part 5 is made of a wear-resistant material such as ceramic.
This shows that combinations of different materials are possible.

Furthermore, FIG. 4 shows a fourth embodiment of the present invention, in which the outer cylindrical portion 6b of the cap 6 is extended downward to form a concave bearing support portion 5a, and the outer cylindrical portion 6b is
Slits 6f extending in the axial direction are formed at several locations, and a convex portion 6g is formed approximately at the center of the inner circumferential wall. Further, the rotation support part 5 has a substantially cylindrical shape,
Moreover, on the outer peripheral surface, there is a recess 5 into which the above-mentioned protrusion 6g can be fitted.
h, and the cap 6 and the rotation support part 5 are integrated through these uneven parts 5h and 6g to form the clearance adjustment part 4 . Also, cap 6
It is characterized in that both side surfaces of the upper end 1b of the support shaft protruding upward from the support shaft are cut into flat surfaces so that they can be used for mounting the guide roller after completion.

Note that the other configurations in the second to fourth embodiments are the same as those in the first embodiment.

(Effects of the invention) As described above, according to the invention, the cylindrical roller 7 has the cylindrical collar 8 fixed to the inner wall surface, and the cylindrical collar 8 has the tapered rotary support surfaces 8a and 8b on the inner surfaces of both ends.
A rod-shaped support shaft 1 disposed passing through the center of the roller 7, a support portion 2 having a ring-shaped inner surface 3a facing one end of the collar 8 and fixed to the support shaft 1, and the collar 8. a clearance adjustment part 4 having a ring-shaped inner surface 5g facing the other end of the collar 8 and attached to the support shaft 1 so as to be freely advanced and retractable by screwing means; one rotation support surface 8a of the collar 8;
A bearing 9 disposed between the inner surface 3a of the support section 2 and the circumferential surface of the support section 1, the other rotational support surface 8b of the collar 8, the inner surface 5g of the clearance adjustment section 4 , and the circumferential surface of the support section 1. Since the rotary support member is equipped with a bearing 10 disposed between the circumferential surfaces, the rotation support member can be processed with high precision, and it can be easily attached to the support shaft, so there is no need to impair accuracy during assembly. This has the advantage that there is no clearance, and the clearance can be easily adjusted.

[Brief explanation of drawings]

Figure 1 shows the first embodiment of the guide roller of the present invention, where Figure A is a plan view, Figure B is a vertical sectional view of the same, and Figure 2 is a longitudinal sectional view of the same.
The figure shows a second embodiment of the present invention, FIG. 3 shows a third embodiment,
Figures 4A and 4B show the fourth embodiment. 1...Support shaft, 2...Support part, 4 ...Clearance adjustment part, 7...Roller, 9, 10...Bearing.

Claims (1)

[Scope of utility model registration request] Tapered rotation support surfaces 8a and 8b on the inner surfaces of both ends
A cylindrical roller 7 having a cylindrical collar 8 fixed to an inner wall surface, a rod-shaped support shaft 1 disposed passing through the center of this roller 7, and a ring-shaped collar 8 facing one end of the collar 8. A support part 2 having an inner surface 3a and fixed to the support shaft 1, and a ring-shaped inner surface 5g facing the other end of the collar 8, is attached to the support shaft 1 by screwing means so as to be movable forward and backward. A bearing 9 disposed between the clearance adjustment part 4 , one rotation support surface 8a of the collar 8, the inner surface 3a of the support part 2, and the circumferential surface of the support part 1, and the rotation support of the other collar 8. surface 8b,
a bearing 10 disposed between the inner surface 5g of the clearance adjustment section 4 and the circumferential surface of the support section 1;
A guide roller comprising: