JPS6042296B2 - Method for manufacturing friction discs - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a method for manufacturing a friction disc, particularly a short annular rotor member whose inner and outer diameters are precisely machined and whose side surfaces are machined with grooves, holes, notches, etc. The present invention relates to a method of forming a core by injection molding its supporting body.

In friction disks used in spinning machines, particularly in spinning machines, general urethane rubber is often used in the yarn twisting section.

The structures of conventional friction disks can be broadly classified into the following three types, which are relatively often used. The first type is a structure in which a core metal made of an inelastic material is used, and liquid rubber is poured around it and hardened. The second type is a structure in which a single piece of rubber is cut into a predetermined shape. The third type is a structure in which a rubber ring is press-fitted or adhered to the outer periphery of a core metal made of an inelastic material. By the way, none of these conventional structures can be used for high-speed rotation. That is, 400,000 to 600,000 rotations is considered to be the limit. This is because the rubber itself is not constrained in any way, or is only partially constrained, and is almost unconstrained, which causes problems such as swelling of the rubber due to centrifugal force and high-speed rotation. This is because it is in a state where it is subject to the pulsation of time. This not only causes variations in the slip ratio, but also causes vibrations, thereby inhibiting high-speed rotation.
Furthermore, according to the conventional rotor manufacturing method using cast liquid rubber, the liquid rubber generally solidifies in 20 to 40 seconds when exposed to the outside air. During the solidification process of the rubber, the rubber solidifies while containing air bubbles, which often form avatar-like pinholes, which directly become oil pools and cause slips, and furthermore generate vibrations on the spinner raceway. This is one of the causes. Indirectly, it becomes a remote cause of the occurrence of cracks and the like. Therefore, in order to prevent such defects, it is necessary to create a core structure that allows air bubbles to escape easily, but if the conventional method is adopted as is, there is no choice but to make the shape that restrains the rubber open. Solidification occurs in a weak form. If this continues, it will not be able to resist centrifugal force or pulsation caused by high-speed rotation, so it will eventually become unusable. This invention was developed in view of the above-mentioned drawbacks of the conventional rubber, and aims to take advantage of the characteristics of urethane rubber and overcome the structural defects of the conventional rubber by wrapping the rubber in an outer frame to ensure smooth high-speed rotation. It is an object of the present invention to provide a bubble-free friction disk made of rubber, and in particular, a method for manufacturing the same, which can be used for various purposes.

The method for manufacturing a friction disc according to the present invention is particularly a spinner type friction disc, in which a short annular rotor member pre-machined with hard polyurethane rubber is used as a core, and its support base is injection molded. It is something to do.

That is, in the conventional method of pouring liquid rubber into a support base and solidifying it, minute pinhole-shaped air bubbles are generated in the annular rotor member when the liquid rubber is fixed, but in the present invention, first, a simple cylindrical By forming the rough material for the rotor with hard urethane rubber that is a superior liquid rubber, pinhole-shaped air bubbles are collected on the inner and outer peripheries of the material during the curing process, and these air bubbles are machined and cut into multiple short dimensions. By cutting into annular rotor members and machining grooves, holes, corners, etc. on the sides of each, defects in the liquid rubber due to pinhole-shaped air bubbles are removed.
It also aims to reduce manufacturing costs.

The manufacturing method of the present invention will be explained below with reference to the drawings.

FIG. 1 is an overall view of a false-twisting spindle incorporating a friction disk according to the present invention.

In the drawing, 1, 1 is a friction disk, 2, 2 is an example of an annular rotor member, 3, 3 is a support base, 4 is a spindle, 5
1 is a spindle shaft, 6 is a cap, and 7 is a contact portion of a belt. The friction disk 1 for the false twisting spindle is
It is manufactured by the method shown below. First, the liquid rubber is cured and the outer diameter (A + 2a) φ is obtained as shown in Fig. 2 A and 2.
? , inner diameter (B-2b) φ? , length approximately 100-500m!
An IL cylindrical rotor rough material 11 is prepared. Before the liquid rubber hardens, air bubbles mixed in the liquid are collected on the inner and outer peripheries of the material. In other words, air bubbles are collected within the ranges A and b on the inner and outer peripheries of the material. From this rotor raw material 11, the part containing air bubbles at the opening in FIG. 2, that is, the outer diameter A7l77!
, inner diameter Bwft is cut by machining, outer diameter Aφ order,
Inner diameter Bφ? To obtain a dense cylindrical rotor material 12 having a precise outer periphery and no air bubbles. This material 12 is cut as shown in FIG. Processed. In addition, this groove, hole, step 14
is a restraining frame for dealing with centrifugal force during rotation and pulsation of the rubber itself. The short annular rotor member 13 thus obtained is sandwiched at its outer periphery between the upper and lower molds shown in FIG. A mold space corresponding to a support base 16 is constructed, and a material such as a synthetic resin that can be injection molded is injected into this mold space 15. In addition, in the drawing, 19 is the upper mold,
20 is a lower mold, 21, 21 are knockout pins, 22 is a synthetic resin injection means, and 23 is a nozzle. Finally, appropriate processing is performed to provide the friction disk shown in FIG. As explained above, this invention cures liquid rubber so that the outer diameter is in the order of (A+2a)φ and the inner diameter is in the order of (B-2b).
) A cylindrical rotor material of a predetermined length with a diameter of φ is made, and the air bubbles mixed in the liquid during the curing process of the liquid rubber are collected within the ranges A and b on the inner and outer peripheries of the material, and this cylindrical rotor is ATfOrL, respectively, the outer diameter part and inner diameter part from the material.
When cutting bTf$L, the outer diameter is Aφ and the inner diameter is Bφ? Obtain a dense cylindrical rotor material with a precise outer circumference and no bubbles.
A short annular rotor member is prepared in advance by cutting this rotor material into a plurality of pieces with a predetermined width and machining grooves, holes, notches, etc. on the side surfaces L1. A mold space with a predetermined support base shape is formed by sandwiching the shell cylinder part and the cylindrical part between molds, and a synthetic resin material that can be injection molded is injected into this mold space to create a highly rigid and centrifugal mold. This method of manufacturing a friction disk having a precision rotor portion that is strong against force has significant effects in terms of precision and cost.

[Brief explanation of the drawing]

FIG. 1 is a drawing showing the overall configuration of a false twisting spindle incorporating a friction disk according to the present invention. FIGS. 2A to 2C are drawings showing a method for manufacturing a cylindrical raw material for obtaining a short annular rotor member according to the present invention,
FIGS. 3A to 3E are drawings showing various shapes thereof. Fourth
The figure shows an injection molding apparatus for a supporting body using a rotor member as a core according to the present invention. And Figure 5 is
It is a drawing showing a completed friction disk. 13... Annular rotor part, 14... Groove, 16... Support base, 17...
... Shell tube part, 18... Cylindrical part.

Claims (1)

[Claims] 1. After curing the liquid rubber, the outer diameter is (A + 2a) φmm,
A cylindrical rotor rough material of a predetermined length with an inner diameter of (B-2b)φmm is made, and air bubbles mixed into the liquid during the curing process of the liquid rubber are placed within the ranges a and b of the inner and outer peripheries of the material. The outer diameter and inner diameter of this cylindrical rotor material are cut by amm and bmm, respectively, so that the outer diameter is Aφmm and the inner diameter is B.
Obtain a dense cylindrical rotor material with a precise outer and inner circumference of φmm and no air bubbles, cut this rotor material into multiple pieces with a predetermined width, and machine the sides with grooves, holes, and notches to shorten the rotor material. Sandwich the outer periphery of the annular rotor member with the upper and lower molds,
This is used as a core to form a mold space with a predetermined support matrix shape consisting of a shell tube part and a cylindrical part, and an injection moldable synthetic resin material etc. is injected into this mold space to have high rigidity and strong resistance to centrifugal force. A method for manufacturing a friction disc having a precise annular rotor member without bubbles.