JPH06147135A - Resin coating method of side plate at gear pump - Google Patents

Abstract

PURPOSE:To prevent resin from being peeled off in the case of molybdenum disulfide or tetrafluoroethylene resin being a coated on side plates consisting of a steel sintered metal. CONSTITUTION:After the sizing of the outforms of the outforms of side plates 4, 5 is carried out, they are immersed in a water soluble anti-rust agent, and then are ground, and after the grinding, the water soluble anti-rust agent is driven out by means of wash and heating, and then, synthetic resin such as molybdenum disulfide or tetrafluoroethylene resin is coated.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a resin coating method for a side plate for maintaining a loading balance of a gear pump.

[0002]

2. Description of the Related Art A side plate made of a sintered metal has been coated with molybdenum difluoride or a tetrafluoroethylene resin in order to improve slidability with a side surface of a gear.
As the coating method, first, the side plate is sintered and formed, and then the side plate is dipped in oil to replace the internal pores of the sintered metal with oil. Further, this side plate is polished to secure its flatness and to make it thick. After this, the side plate is washed, but at this time, since the oil has soaked into the internal porous material, the side plate does not rust. The side plate is thoroughly washed, and then molybdenum disulfide or tetrafluoroethylene resin is baked and coated around the side plate.

In the conventional coating method as described above, since the synthetic resin is baked after oil immersion, the oil oozes out during the baking. Therefore, the adhesive strength of the coated resin becomes extremely weak, and there is a problem that the coated resin peels off when the gear pump is used. An object of the present invention is to provide a resin coating method for a side plate in which the coated resin does not come off.

[0004]

According to the present invention, in a gear pump in which a pair of gears are incorporated in a body and side plates are provided on the side surfaces of the gears, the side plates are made of sintered metal, while the side plates are made of sintered metal. After sizing the outer shape of the product, dip it in a water-soluble rust preventive agent and polish it, then wash and heat it to drive out the water-soluble rust preventive agent, and then synthesize molybdenum difluoride or tetrafluoroethylene resin, etc. It has a feature in that it is coated with resin.

[0005]

Since the present invention is constructed as described above, the porous rust preventive agent is replaced with air by immersing it in a water-soluble rust preventive agent, washing it, and then heating it.

According to the coating method of the present invention,
After heating the side plate impregnated with the water-soluble rust preventive agent to replace the rust preventive agent filled in the pores with air,
Since it is coated with resin, oil does not seep out during the coating. Since the oil does not seep out in this way, the adhesive force of the resin to the side plate is not weakened, and therefore the coated resin does not peel off during use.

[0006]

1 and 2 show a gear pump,
In this gear pump, a pair of gears 2 and 3 are incorporated in a body bore 1 of a body B, and side plates 4 and 5 are provided on both sides of the gears 2 and 3, respectively. One side of the body B thus configured is covered with the mounting flange M, and the other side is covered with the cover C. Each of the gear shafts 6 to 9 of the gears 2 and 3 is rotatably supported by the winding bushes 10 to 13 press-fitted into the mounting flange M and the cover C.

The above-mentioned body B is made of iron, and the side plates 4, 5 are made of iron-based sintered metal. Then, the side plates 4 and 5 are coated with molybdenum disulfide or ethylene tetrafluoride resin, which is performed as follows. The side plates 4 and 5 are molded into an 8-shape as shown in FIG. 2, and then the outer shape thereof is sized. After that, the side plates 4 and 5 are dipped in a water-soluble rust preventive agent, and the pores therein are replaced with the water-soluble rust preventive agent.

The side plates 4 and 5 whose inner pores are replaced with a water-soluble rust preventive agent are polished to ensure their flatness and to be thickened. When this polishing operation is completed, this time, it is washed with water and heated sufficiently. By this heating, the water-soluble rust preventive agent is expelled from the internal pores of the side plates 4 and 5. After replacing the inner porous with air, molybdenum disulfide or tetrafluoroethylene resin is coated around it. Therefore, at the time of coating with this resin, oil does not exude from the internal porous material, and as a matter of course, the peel resistance of the coated resin is sufficiently maintained.

[Brief description of drawings]

FIG. 1 is a cross-sectional view of a gear pump using a side plate.

FIG. 2 is a sectional view taken along line II-II in FIG.

[Code]

 B body 2 gear 3 gear 4 side plate 5 side plate

Claims (1)

[Claims] 1. In a gear pump having a body in which a pair of gears are incorporated and side plates provided on the side surfaces of the gears, the side plates are made of sintered metal, and after sizing the outer shape of the side plates, Side that is made by immersing in water-soluble rust preventative agent, then polishing, washing and heating after that to drive out water-soluble rust preventive agent, and then coating synthetic resin such as molybdenum disulfide or tetrafluoroethylene resin Plate coating method.