1. Field of the Invention
This invention relates to a compressor member such as a scroll member for scroll compressor, to a manufacturing method for the material, and to a scroll compressor.
2. Description of Related Art
Scroll compressors are one type of compressor used in freezing systems or air conditioning systems and are compressors performing compression by means of a stationary scroll and an orbiting scroll that orbits according to rotation of a drive shaft. Any scroll of conventional scroll compressors is made from some iron or aluminum material. Those metal scrolls, however, had a problem causing high costs for production because they require a relatively high precision to be fabricated. Furthermore, the metal scrolls are heavy in weight and therefore raise a problem that the compressors suffer from large energy losses when operating.
Previous inventors have developed scrolls mainly made of a resin suitable to be fabricated and light in weight in comparison with metal scrolls and have proposed various scrolls (e.g., Japanese Unexamined Patent Publication (KOKAI) No. Showa 62-199,981, Japanese Unexamined Patent Publication (KOKAI) No. Heisei 2-112,685, Japanese Unexamined Patent Publication (KOKAI) No. Heisei 2-112,688, Japanese Patent Publication (KOKOKU) No. Heisei 6-33,780).
Those scrolls mainly made of a resin have not yet been practically produced. Although various searches for scroll materials have focused on their resistance against abrasion, research done by this inventor discovered that there were other practical characteristics to be considered in addition to resistance against abrasion. That is, the scrolls in the scroll compressors are in contact with refrigerant and refrigerating machine oil at a high temperature and a high pressure during operation of the compressors. Scrolls mainly made of a resin in contact with the refrigerant and refrigerating machine oil at the high temperature and the high pressure change in dimension, thereby causing a problem in that the scroll prevents the compressor from operating efficiently and possibly makes it inoperable. The research concluded that to make the scroll practical, the scroll needs to be made of a material having dimensional and chemical stability under high temperature and high pressure refrigerant and refrigerating machine oil, as well as abrasion resistance.
Various engineering plastics are considered to be used for some mechanical parts other than scrolls in scroll compressors, and are in fact, used in many fields. Particularly, those are frequently parts of automobiles. For example, known as mainly made of a phenol aralkyl resin are pulleys (e.g., Japanese Patent Publication (KOKOKU) No. Heisei 4-38,944, Japanese Patent Publication (KOKOKU) No. Heisei 4-38,945), rotors for pump (e.g., Publications of U.S. Pat. Nos. 2,643,476 and 2,643,477), and impellers for pump (e.g., Japanese Unexamined Patent Publication (KOKAI) No. Heisei 8-93,690, Japanese Unexamined Patent Publication (KOKAI) No. Heisei 9-112,489).
However, in all of the above cases, no material is selected in consideration for dimensional and chemical stability under high temperature and high pressure refrigerant and refrigerating machine oil, as well as abrasion resistance.