| 摘要 |
<p>A compressor (10; 100; 200; 300; 500) with a build-in reciprocating motor, comprises a cylindrical housing (20; 120; 210; 510) with two ends thereof fitted with tow opposing electromagnets (30; 130; 230; 530), each has a circular inner pole (36; 136) and a coaxial annular outer pole (34; 134). A free piston (50; 150; 250; 560; 600) is disposed in the housing between the two electromagnets, dividing the interior of the housing into two chambers (I, II). The piston carries permanent magnets (40; 140, 145; 561; 610), providing inner and outer poles (44, 46; 141, 146) which have conical surface portions (43, 49; 141, 146) complementary with the corresponding poles (34, 36; 134, 136) of the electomagnets. Sliding pole pieces (630 and 660) can be used to increase the stroke length and reduce the piston's total weight. Valves (61, 63, 65; 161, 165) are fitted to form one-way flow passage connecting the inlet and the outlet of the compressor. In operation, the complementary surfaces of the electromagnets and the permanent magnets form concentric forces which drive the free piston axially while keeping it magnetically suspended, so as to minimize the frictional resistance to the piston's movements and to reduce its wear to minimum. Buffer mechanisms, including air, spring and/or magnetic cushioning, are formed between the piston and each of the electromagnets to prevent direct physical impact between them. A movable support (280; 580) provides automatic adjustment of piston's stroke length in response to changes of output pressure. A circuit (285, 283, 212, 211, 221) is formed to circulate a lubricant for keeping the piston lubricated. Magnetic coupling arrangement (570, 545, 555) is made to further improve the compressor's energy efficiency. In application, a number of the compressors can be connected in series to build up a high pressure output.</p> |
