JPS6267327A - Plain bearing - Google Patents

Abstract

PURPOSE:To shorten molding time by forming an external drum around the external surface of an internal drum and arranging the internal drum within an injection mold metal for injecting resin for the external drum. CONSTITUTION:A drag 31 for injection molding is provided with a molded recess part 31a of the same shape as the external form of an external drum 3, and a support pin 32 of outer diameter equal to the inner diameter of an external drum 2 is erected at the center of the recess part 31a. And the internal drum 2 is mounted to the support pin 32. In this state, a cope 33 is closed and fibre reinforced resin 3a is injected into a cavity formed by the drag 31 and the cope 33, from the resin passage 33a of the cope 33. Consequently, the external drum 3 is formed around the external surface of the internal drum 2, thereby simplifying a manufacture process very much and shortening molding time.

Description

Detailed Description of the Invention (Field of Industrial Application) The present invention relates to a resin sliding bearing used, for example, in a held-type automatic transmission for a small snowmobile, and in particular to simplifying the manufacturing process and reducing the manufacturing time. Regarding improving productivity by shortening the time.

[Conventional technology]

In general, resin sliding bearings are used for shafts that are difficult to lubricate with oil due to equipment reasons, or are preferable to be used without lubrication, such as the weight support shaft that moves the movable sheep of the automatic transmission mentioned above. Used for support etc. As an example of such a sliding bearing, there has conventionally been one that consists of an inner cylinder that slides on the shaft and an outer cylinder that is formed around the outer circumference of the inner cylinder and fixed by an external member. The inner cylinder is formed by winding a sheet made of a woven fabric of fluororesin fibers hardened with an epoxy resin onto a mandrel using a sheet winding method. Further, the outer cylinder is formed by winding long fibers such as metal or glass around the outer periphery of the inner cylinder by a filament winding method (hereinafter referred to as FW method).

(Problems to be Solved by the Invention) In the above-mentioned conventional flat bearing, the outer cylinder is formed by the FW method, but when using the FW method, generally the long fibers are impregnated with resin and the inner cylinder is There is a problem in that the long fibers are wound around the inner cylinder while the cylinder is rotated, which requires a lot of time and effort in manufacturing, and the productivity is low.

The present invention has been made to solve these conventional problems, and aims to provide a sliding bearing that has a very simple manufacturing process, requires only a short molding time, and can improve productivity. The purpose is

[Means for Solving the Problems] Accordingly, the present invention provides a sliding bearing in which the inner cylinder that makes sliding contact with the shaft is formed using a woven fabric hardened with resin, and the outer periphery of the inner cylinder is made of fiber-reinforced resin. An outer cylinder fixed to an external member is formed by injection molding.

Here, the shaft of the present invention includes both a rotating shaft and a fixed shaft, and the external members include a member that supports the shaft through the main bearing and a member that is conversely supported by the shaft through the main bearing.

[Effect]

In the sliding bearing according to the present invention, the outer cylinder is formed on the outer periphery of the inner cylinder by the injection molding method, so it is very simple to simply place the inner cylinder in the injection mold and inject the resin for the outer cylinder. It can be manufactured in a simple process and in a short molding time, which improves productivity accordingly.

(Example〕 Embodiments of the present invention will be described below with reference to the drawings.

1 to 4 are for explaining one embodiment of the present invention.

FIG. 3 shows the drive side portion of a belt-type automatic transmission for a small snowmobile in which the sliding bearing of this embodiment is used. In the figure, 10 is a primary sheave, which fits the primary shaft 11 to one end of the crankshaft 21 of the engine.
Both are fixed with bolts 17, fixed sheave 12 and movable sheave 13 are attached to the primary shaft 11 facing each other, a stopper member 14 is fixed to the outside thereof, and a cap 15 is provided via a spring 16. It is configured as follows. A weight 18 is rotatably attached to the movable sheave 13, and a collar 19 is rotatably attached to the outside of the weight 18 of the stopper member 14, and the weight 18, collar 19 and support pin The sliding bearing 1 of this embodiment is arranged between the bearings 20a and 20b.

This primary sheave 10 rotates when the engine starts, and due to its centrifugal force as the engine rotational speed changes, i! 18 swings around the support pin 20a and comes into contact with the collar 19, which causes the movable knob 13 to slide and change the distance between it and the fixed sheave 12. In other words, the sheave diameter of the heald 22 changes and the rotational speed increases. changes.

The slide bearing 1 is composed of an inner cylinder 2 and an outer cylinder 3. The inner cylinder 2 has a shaft, in this case a support pin 20a,
It constitutes a bearing surface that comes into sliding contact with 20b. As shown in FIGS. 1 and 2, this inner cylinder 2 consists of long fibers 2a and resin 2b.
It is made from a woven fabric that has been hardened by molding it into a cylindrical shape.

Various types of fibers made of substances with a small coefficient of friction can be used as the woven fibers 2a, and for example, fluororesin fibers such as polytetrafluoroethylene (PTFE) or carbon fibers are most suitable. These fibers are Il! This is because the friction coefficient of Fj is small and it has self-lubricating properties, so even when used without lubrication, the frictional resistance can be reduced, and the loss of Fj friction can be minimized. Further, as the resin 2b for hardening the woven fabric, epoxy resin or polyester resin can be used.

The outer cylinder 3 constitutes a support part that supports an external member, in this case a weight 18 or a collar 19, and a resin 3a reinforced with short fibers 3b is formed on the outer periphery of the inner cylinder 2 by injection molding. It has a cylindrical shape.

As the resin 3a for the outer cylinder 3, any resin can be used as long as it can be injection molded and has a high compressive strength, but in particular polyamide, polyacetal, polyphenylsulfide (PPS), polypropylene (PP), etc. So-called engineering plastics with high compressive strength are optimal. Further, as the reinforcing short fibers 3b of the resin 3a for the outer cylinder 3, glass fibers, whiskers, rock wool, etc. can be used.

Here, to outline the manufacturing procedure of the sliding bearing 1 by the injection molding method which is a feature of this embodiment, a molded portion 31a having the same external shape as the outer cylinder 3 is recessed in the lower mold 31 for injection molding, A support pin 32 having the same outer diameter as the inner diameter of the inner cylinder 2 is provided upright in the center of the recess 31a. Then, the inner cylinder 2 is attached to the support pin 32, and the upper mold 33 is closed in this state, and then the resin passage 33a of the upper mold 33 is inserted into the cavity formed by the lower mold 31 and the upper mold 33. Inject the resin 3a. As a result, an outer cylinder 3 is formed around the outer periphery of the inner cylinder 2.

In this example, since the outer cylinder 3 was formed on the outer periphery of the inner cylinder 2 by injection molding, the manufacturing process was much simpler and the molding time was shorter than when using the conventional FW method. This can improve productivity.

In addition, the resin 33 layer of the outer cylinder 3 has support pins 20a or 20b.
The inner cylinder 2 plays the role of absorbing vibrations from the
The vibration load acting on the inner cylinder 2 is reduced, and the wear of the inner cylinder 2 is suppressed.

Furthermore, since the inner cylinder 2 is made of fluororesin fiber or the like that has a small Fj friction coefficient and is self-lubricating, it can be used even in an unlubricated state, and even in this case, the frictional resistance is small and friction loss can be reduced.

In the above embodiment, the description was given of the case where the shaft is fixed and the weight 1B and the collar 19 rotate in a belt-type automatic transmission; Furthermore, the sliding bearing of the present invention can be used to support any shaft other than those for snowmobiles, and is particularly effective when used in a non-lubricated state.

〔Effect of the invention〕

As described above, according to the sliding bearing according to the present invention, since the outer cylinder is formed by injection molding using fiber-reinforced resin on the outer periphery of the inner cylinder, manufacturing is simple, the molding time is shortened, and production is easy. It has the effect of improving sex.

[Brief explanation of drawings]

Fig. 1 is an enlarged sectional view of essential parts of a sliding bearing according to an embodiment of the present invention, Fig. 2 is a perspective view of the above embodiment, and Fig. 3 is a cross section of a primary sheave in which the above embodiment bearing is used. FIG. 4 is a sectional view showing an injection mold. In the figure, ■ is a sliding bearing, 2 is an inner cylinder, 2b is a resin for solidifying woven fabric, 3 is an outer cylinder, 3a is a fiber reinforced resin, 18.19
is a weight, a collar (external member), and 20a and 20b are support bottles (shafts). Figure 1 Figure 2 Figure 4 Figure 3 Procedural amendment (voice) October 31, 1985

Claims (1)

[Claims] (1) An inner tube that slides on the shaft is formed into a cylindrical shape using a woven fabric hardened with resin, and an outer tube that is fixed to an external member by injection molding using fiber-reinforced resin on the outer periphery of the inner tube. A sliding bearing characterized by having a cylinder formed into a cylindrical shape.