Patent Application
20070295577
Exemplary embodiments of the invention will be described with reference to drawings. In the exemplary embodiments, a case of manufacturing a pressure plate for brake pads of automobiles is described as an example. However, the method of manufacturing a friction member according to the invention is not limited to the exemplary embodiments.
In Step S02, the pressure plate 10 subjected to the degreasing step is cleaned. Specifically, the pressure plate 10 is washed with hot water. In Step S03, the pressure plate 10 after cleaning is dried. Specifically, the pressure plate 10 after cleaning is dried in a drying furnace at a temperature of 80° C. for about 1 to 2 minutes.
In Step S04, a shot material 1 is shot to the pressure plate 10.
In Step S05, a powder adhesive is applied on the surface, more specifically the film of the pressure plate 10. Specifically, a phenol resin-based powder adhesive having a particle diameter of 25 μm is statistically applied on the surface of the pressure plate 10 by a corona charging method. Namely, a charged powder adhesive is applied on the surface of the earthed pressure plate 10. After the application of the powder adhesive, the applied plate is heated under a temperature of 130° C. for about 15 minutes to form an adhesive layer having a thickness of 30 to 40 μm.
In Step S06, a pre-formed product of a friction material is overlaid on the adhesive layer of the pressure plate 10, which is then subjected to a pre-heating treatment. More specifically, heat at about 100 to 140° C. is applied for 5 to 15 minutes in a state of overlaying the pre-formed product of the friction material and the pressure plate 10. Thereby, the adhesive can be converted into a flow state before curing.
In Step S07, the pressure plate 10 subjected to the pre-heating is subjected to a thermal forming treatment. More specifically, heat at 130 to 200° C. is applied to the pressure plate 10 subjected to the pre-heating treatment and the pre-formed product of the friction material under a pressure of 20 to 100 MPa. Thereby, forming of the friction material and adhesion of the friction material and the pressure plate can be conducted at the same time.
In Step S08, there is conducted a heating treatment (after-cure) of the pressure plate 10 where the thermal forming treatment has been completed. More specifically, heat at 150 to 300° C. is applied for 1 to 15 hours. Thereby, curing of the binder and the adhesive in the friction material is completed.
Next, one example of the method of manufacturing a friction member according to the conventional art is described. Furthermore, the above-mentioned method of manufacturing a friction member according to the first exemplary embodiment is explained in comparison with the method of manufacturing a friction member according to the conventional art.
In Step S14, the pressure plate is dipped in a ceramic precursor solution. The ceramic precursor solution is prepared by mixing triethoxymethylsilane and acetic acid in a molar ratio of 1:4 with ethanol as a solvent to dissolve them, adding polyvinylbutyral in a ratio of 5 wt % in a film, and heating the whole at a temperature of 70° C. for 3 hours to concentrate it so as to be 1 mol/l.
In Step S15, the pressure plate dipped in the precursor is drawn up at a constant rate of 800 mm/min and then heated at a temperature of 150° C. for 3 hours. Thereby, a film having a thickness of 500 to 1000 nm is formed on the surface of the pressure plate. Thereafter, the plate is cooled for a predetermined time and then an iron phosphate film is further formed and a primer treatment is conducted, that is, a primer agent is applied on the iron phosphate film (Step S16). In this connection, the iron phosphate film had a film weight of 0.4 to 0.8 g/m2. Moreover, a phenol-based resin was used as a primer agent and the thickness of the primer layer was from 5 to 20 μm.
In Step S17, the pressure plate subjected to the primer treatment is subjected to a pre-curing treatment. Then, in Step S18, an adhesive is applied. As the adhesive, a thermosetting adhesive was used. In Step S19, the pressure plate after the application of the adhesive is dried. After drying of the pressure plate, a heating treatment, a thermal forming treatment, and a heating treatment of the pressure plate are conducted in Step S20 to Step S22. In this connection, the pre-heating treatment, thermal forming treatment, and thermal curing treatment can be conducted in the same procedures as in Step S06 to Step S08 described in the method of manufacturing a friction member according to the first exemplary embodiment. Therefore, detailed description thereof is omitted.
When the method of manufacturing a friction member according to the conventional art and the method of manufacturing a friction member according to the first exemplary embodiment described in the above are compared, the method of manufacturing a friction member according to the conventional art comprises a chemical treatment of forming an iron phosphate film and also a primer treatment. However, in the method of manufacturing a friction member according to the first exemplary embodiment, since the chemical treatment and the primer treatment are not conducted, a solvent or the like required in the chemical treatment and the primer treatment is not used, so that an environmental burden such as renewal of a liquid for chemical conversion and washing with water can be reduced.
Moreover, in the method of manufacturing a friction member according to the first exemplary embodiment, since no solvent is used and the shot material is shot under a dry condition, there arise no problem of storage and preservation of a solution. Also, the influence of smell on workers is diminished and thus safety of the workers can be secured as well as an environmental hygiene problem can be reduced.
Furthermore, in the method of manufacturing a friction member according to the first exemplary embodiment, the adhesion of the friction material is achieved without any primer treatment that is hitherto required and hence the number of steps is reduced. Thereby, the method of manufacturing a friction member according to the first exemplary embodiment can realize reduction of equipment expenses, space-saving, and reduction of running costs.
In addition, since the brake pad produced by the method of manufacturing a friction member according to the first exemplary embodiment does not have a primer layer, peeling-off that is a concern of a brake pad having a primer layer is inhibited and adhesiveness is improved, so that the quality is stabilized. Namely, quality equal to or higher than that of the conventional friction members can be secured.
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It will be apparent to those skilled in the art that various modifications and variations can be made to the described embodiments of the present invention without departing from the spirit or scope of the invention. Thus, it is intended that the present invention cover all modifications and variations of this invention consistent with the scope of the appended claims and their equivalents.
| Number | Date | Country | Kind |
|---|---|---|---|
| 2006-175155 | Jun 2006 | JP | national |
