JPS59212523A - Bearing consisting of synthetic resin laminated molded material and its manufacture - Google Patents

Abstract

PURPOSE:To increase the junction strength of both layers, by integrally forming the sliding surface layer consisting of a tetrafluoroethylene resin thin plate with the reinforced layer, formed by a multiple-lap wound layer of resin cloth comprising thermo-setting synthetic resin and a cloth base material, through a wire mesh. CONSTITUTION:Winding a tetrafluoroethylene resin thin plate 6 on a core metal 1, a sliding surface layer is formed and its top is coated with a wire mesh 7. Next, further on its top winding a resin cloth 9, consisting of thermo-setting synthetic resin and cloth base material, to be piled in layers, a laminated reinforced layer 8 is formed. Then if the reinforced layer 8 reaches a prescribed size, cutting the resin cloth 9 to be wound then removing a molded material with the core metal 1 from a molding machine, the molded material is transferred to a heating furnace with the core metal 1, thus performing curing. Finally cutting this material to a prescribed length, a bearing bush is completed.

Description

[Detailed description of the invention] Kidai Akari, ethylene trifluoride 9', 8if rPTF
E) Intermediate layer consisting of a sliding surface layer made of Ig% and a wire mesh; transfer consisting of a divine labor layer formed with multiple layers of pus cloth (6) layers, and its manufacturing method. Conventionally, the inner layer is made of PTFE, the outer layer is made of other synthetic resin, and the outer layer is made of other synthetic resin. There are Japanese Patent Publication No. 47-50893, Japanese Patent Publication No. 56-8045, and Japanese Patent Application Laid-Open No. 54-3892, all of which use PTFE to form the sliding surface.
However, since it is made of a mixed woven fabric of PTFE fibers and other fibers, if there is a problem with dimensional accuracy or if it is necessary to expand the diameter, this inner sliding surface layer can be cut by cutting. There was a problem that it could not be corrected. In other words, the mixed woven fabric that forms the sliding surface was cut by a knife.
As a result, the bearing performance will be significantly reduced.
It's coming.

Furthermore, for products lined with PTFE mixed woven fabric, the adhesive used to bond the reinforcing layer to the woven fabric surface (sliding surface) during molding.
There is a problem that PTFE has a tendency to seep into the surface and scratch the surface, impairing the low friction properties originally possessed by PTFE.

When a product in this condition is used, especially under heavy load conditions, the frictional torque is large and the lining layer often peels off.
Therefore, in this type of bearing, the dimensional accuracy of the core metal is extremely dependent on the type of resin and material used, the degree of drying (hardening) of the resin cloth and primer-treated surface, and other factors. A satisfactory product cannot be obtained unless the molding conditions, key cylinder conditions, etc. are strictly controlled.If the inner sliding surface layer can be cut and there is no need to worry about adhesive seepage, If this is done, even if there are some disadvantages such as the addition of one step or the generation of cutting waste, the advantages in production are actually greater than the above-mentioned method of solving problems through strict management. It can be said that.

From this viewpoint, the present inventors conducted extensive research in an attempt to solve the above-mentioned problems, and came up with the present invention.

That is, by using a thin plate of filled or unfilled PTFE, one side of which has been subjected to a defluoridation treatment, as the sliding surface layer, the above-mentioned cutting problems and adhesive oozing problems were solved.

In order to increase the bonding strength between this PTFE thin plate and the multi-wound reinforcing layer made of resin cloth, a wire mesh is placed between them as an intermediate layer, and the wire mesh is cut into the mesh of the wire. A desired bearing product was obtained by combining the fluorine-free surface of the PTFE and the resin cloth with adhesion through the wire mesh.

The present invention is characterized in that this mechanical engagement and adhesion are effectively performed by employing a roll forming technique.

The present invention will be explained in detail below.

First, a PTFE thin plate whose one side has been subjected to a dehydration treatment is prepared. The diameter of the PTFE thin plate differs depending on the diameter of the bearing to be obtained, but it is usually about 0.6 to 5 meters, especially 0.5 to 6 meters.
A thickness of m is used.

PTFE can be used as an unfilled commercially available thin plate, but as a sliding material, materials such as graphite and molybdenum disulfide are used to improve wear resistance and load carrying capacity without impairing the low friction properties. It is more preferable to use a filled PTFE thin plate mixed with solid lubricant powder, metal powder, or inorganic powder.

If the PTFE thin plate has already been defluorinated when the thin plate is delivered from the manufacturer, it can be used as is; otherwise, it can be treated with a treatment agent (
For example, it is processed using Junkosha's "Tetra Etch"). The deflating treatment is carried out for the purpose of increasing the adhesive strength with the reinforcing layer, but it is more preferable to apply a primer to the treated surface prior to winding and lamination molding.

As the primer, a varnish made of the same type of thermosetting synthetic resin used for resin cloth is generally used. After applying the varnish, remove the solvent before moving on to the next step.

The PTFE thin plate pretreated in this way can be wrapped in a single layer around the core metal with the treated side facing outward.

The winding around the core metal can be exemplified in two ways.

In other words, the width of the # plate is determined in advance according to the same circumferential length of the core metal, and when it is wound around the core metal, the winding start and winding end edges should be wrapped in a single layer so that they do not overlap at least. Can be wrapped.

Another method is to cut PTF into strips with a certain width.
A sliding surface layer is obtained by preparing an E m plate and wrapping it in a single layer around a core metal, each of which has a small side edge. Here, "at least not overlapping" means that the windings may be wound in such a way that their edges or side lines abut each other.

During this winding, the PTFE thin plate was heated (
When used at a temperature of approximately 120° C.), it becomes more flexible and can be easily wrapped.

For products that have been immediately primed, if the coated brimer is heated and dried at a temperature of around 120°C (solvent removed) and then immediately used for wrapping, there is no need to reheat the thin plate when wrapping. .

Next, a wire mesh is fitted onto this PTFE wound layer.

The wire mesh used is, for example, a wire mesh that is woven into 1 piece of 3 to 5 stitches. Braided wire meshes made of stainless steel gauze, nickel silver wire, phosphor bronze wire, etc. are suitable, and those made of soft metal wires are preferable because the resin does not penetrate sufficiently.

Since the bag-knitted wire mesh can be expanded to some extent in the radial direction and has elasticity, if you use a bag-knitted wire mesh that is slightly smaller than the outer diameter of the PTFE-wound layer, it will fit perfectly and be covered. It can be fitted.

This wire mesh can be used, for example, to make a sheet-like mesh into PT
It is also possible to spirally wrap the FE layer on top of the FE layer, but if you expand the diameter of a bag-knitted net and use it, there are no seams between the nets, so you can wrap it evenly. It is immediately superior in homogeneity.

A resin cloth obtained by applying a thermosetting synthetic resin varnish such as phenol resin, epoxy resin, or polyester resin is placed on top of this wire mesh intermediate layer and wrapped under heat and pressure to form a laminated reinforcing layer. .

For this lamination molding, the roll molding method described below is used.

The finished product is removed from the roll molding machine along with the core metal, and is heated to the curing temperature of the resin (approximately 130 to 180°C).
Curing proceeds in a heated atmosphere without external pressure. It is preferable to keep the curing temperature relatively low and to take a slightly long curing time.

When using phenolic resin, the standard hardening time is about 6 hours at a temperature of 135±5℃, but if the diameter of the bearing is large or the thickness of the reinforcing layer is thick (for example, 10mm), the curing time may be longer. It is necessary to take longer.

During this treatment (keering) process in a heated atmosphere, the molded product undergoes thermal expansion of the core metal and shrinkage due to the progress of hardening of the molded product. ? i, a dominant force in the radial direction is generated, resulting in a dense molded product.

The radial compressive force generated in this curing process is greater than the pressure exerted by the rolls during laminated molding of resin cloth, and the holding time in the heated atmosphere is also shorter than the heating time during molding. noticeably long.

Therefore, the biting of the wire mesh into the PTFE thin layer forming the sliding surface layer and the resin cloth forming the reinforcing layer occurs during molding, but is completed during the gearing process.

Moreover, adhesion between the PTFE treated surface and the resin cloth is completed at this point.

When the molded product is removed after the curing process for a predetermined period of time, the molded product will still shrink slightly, so the molded product is left to stand until the size of the molded product has subsided.

This curing process and the release after removing the core metal? The molded product that has passed through l is the beginning and end of winding f of the PTFE thin plate.
Even if a slight gap exists between the edges or the edges of A11 in the case of spiral winding, this gap is almost completely closed.

The cylindrical treetop thus obtained 1. ．． ,7 The molded product (up to a length of about 4 meters is possible) is cut to an appropriate length depending on the application, and by lightly machining the inner and outer diameters, it has a PTFE sliding surface layer on the inside and a thin layer on the outside. A bearing made of a synthetic resin laminate molded product is obtained, which has a reinforcing layer made of a curable synthetic resin, and a wire mesh intermediate layer between the two to firmly connect the two. Of course, in applications where high dimensional accuracy is required, the PTFE inner diameter surface as molded may be used as the sliding surface.

The filter cloth base material used in the resin cloth of the present invention is preferably a cloth made of polyester fibers (trade name: Tetron), or a blended or interwoven cloth made of polyester fibers and cotton fibers.

In addition, cotton cloth can also be used, but inorganic cotton cloth made of glass fiber, asbestos fiber, carbon fiber, etc. is preferable for heat-resistant applications.

The above-mentioned polyester or a blend containing polyester,
Mixed woven fabrics have low hygroscopicity, so there is almost no swelling due to moisture absorption.
It has excellent dimensional stability as a bearing, and since the thermal acid @rj in the O-keering process is large, the compressive force generated in the molded product is large due to the thermal expansion of the core metal.
Therefore, the wire mesh intermediate layer penetrates into the resin well, and not only the bonding force between the PTFE sliding surface layer and the reinforcing layer is large, but also the molded product as a whole becomes a dense molded product.

θResin cloth should have excellent manufacturing and moldability.

It has the following advantages, and is particularly preferable as a general-purpose base material used in the present invention.

FIG. 1 shows a principle diagram of the roll forming method used to manufacture a bearing made of an 81# layer molded product of the present invention.
1) is a core metal, (2) is a pressure roller, +31 +41 is a heating roller, and (5) is a guide roller.

The core metal is located in a position surrounded by these three rollers, and rotational drive is given to the core metal, and the six rollers contact and follow this.

FIG. 2 is a plan view showing the PTFEM wound around the core metal and the wire mesh covered on the thin plate, and FIG. 3 is a cross-sectional view showing the state in which lamination molding has progressed.

(6) is a winding layer (sliding surface layer) made of PTli'E thin plate
- (7) is a wire mesh, (8) is a laminated reinforcing layer, and (9) is a resin cloth used for forming the reinforcing layer.

Once the reinforcing layer has reached a predetermined diameter (wall thickness) after being rolled in this way, the resin cloth is cut and rolled up, the molded product along with the core metal is removed from the molding machine, and it is placed in the heating furnace together with the core metal. Move and key ring.

FIG. 4 is a shaved view of a bearing pusher obtained by cutting a cylindrical and tubular laminated molded product at one location.

Compared to molded products made by compression molding using a mold, products made by roll molding are more uniform and beautiful because there are no disturbances in the base material layer or resin flow marks on the laminated reinforcing layer, It is obtained as a cylindrical and tubular laminated molded product, which is cut into 1
It is easy to manufacture because the bearing can be made to the desired length by placing the bearing in place, and it does not require the use of expensive molds.
Moreover, it has the advantage that it has a great degree of freedom in terms of dimensions, particularly in terms of the outer diameter dimension, by adjusting the number of layers of winding.

The thus obtained bearing of the present invention has no oozing of adhesive or the like on the sliding surface, has an intermediate layer, and has /#iti It also has many advantages, such as being able to withstand use under heavy load conditions and having excellent mechanical strength due to its laminated structure.

[Brief explanation of the drawing]

FIG. 1 shows the principle of the roll forming method used for manufacturing the shaft tube made of the laminate molded product of the present invention. Fig. 2 is a plan view showing the P'l'F''E latent wrapped around the core metal and the wire mesh covered on the thin plate, and Fig. 6 is a top view showing the state in which lamination molding has progressed. The top view and FIG. 4 are perspective views of the bearing fitting of the present invention. ('Sliding surface layer), +7>wire mesh, (8) I layer reinforcement) tl, (9) Resin cloth patent applicant Unipla Co., Ltd. Ne1 Oiles Industries Co., Ltd.

Claims (2)

[Claims] (1) Sequentially from inner layer 11j, a sliding surface layer made of a thin plate of filled or unfilled tetrafluorinated ethylene resin, an intermediate layer made of wire mesh, and a V-hard plastic material and a fabric base material. It consists of a layer made of multiple wound layers of resin cloth, and both the core tetrafluoroethylene cloth and the thin 5Q cloth fill the holes of the wire mesh in the middle layer and are in close contact with each other. Fi9. The three parties are integrated into Kujikan through the cough middle layer. ii) A bearing made of a resin laminated molded product. (2) (a) A thin plate consisting of a fluorinated ethylene sheet-4 treated with fluorine on one side, with this treated side on the outside;
2) Wrap it around the core metal in a single layer to shape the rainbow surface layer, and 2) Cover the wire mesh on top of the easily attached ethylene 71 finger thin layer (1). =-)
A resin cloth made of a thermosetting synthetic resin and a cloth base material is applied to the exposed wire mesh sheet. Therefore, by winding the lees layer in multiple layers to form the shape of the Sodaya layer (
=) This can be heated together with the core metal in an atmosphere of 11A without being pressurized from the outside! / tree 11ti
(G) Then, the core metal is removed and the qQed cylindrical and tubular waste molded product is cut to a predetermined length. A method for manufacturing a bearing made of a phosphorus shaped material