| 摘要 |
A capacity control valve (17) for use in a clutchless, variable capacity compressor includes a central rod plunger (34) that is shifted axially in one direction, against a spring (39), by an energized coil (40), when the compressor is in a greater than minimum capacity condition. For the minimum capacity position, the rod plunger (34) is released by the de energized coil (40) to be pushed by spring (39) in the opposite direction to a solid, pre determined position. A by pass passage (42) interconnecting a discharge pressure chamber (20) and a suction pressure chamber (26) runs in parallel to the rod plunger (34), normally closed off by its own spring loaded shut off valve (44). When the coil 40 is de energized to release the plunger (34), it engages the shut off valve, opening the by pass passage and opening the discharge pressure chamber (20 to the suction pressure chamber (26). This creates a refrigerant recirculation path, internal to the valve (17), for the small refrigerant flow that is still pumped by the compressor at minimum stroke. |
