Variable capacity compressor having a capacity control system using an electromagnetic valve

Claim 1

In a variable capacity compressor including a suction chamber, a discharging space within which discharge pressure prevails, a control element for determining timing of start of compression of a refrigerant gas, said control element having a pressure-receiving portion, a low-pressure chamber within which prevails suction pressure acting on said pressure-receiving portion of said control element, urging means cooperating with said suction pressure for urging said control element toward a minimum capacity position thereof, a high-pressure chamber within which prevails control pressure acting on said pressure-receiving portion of said control element for urging said control element toward a maximum capacity position thereof, high pressure-introducing passage means for introducing said refrigerant gas from said discharging space into said high-pressure chamber to create said control pressure therein, said high pressure-introducing passage means having a restriction hole for restricting flow of said refrigerant gas, a passage for communicating said high-pressure chamber with said suction chamber, a valve body for opening and closing said passage, a plunger, a coiled spring urging said valve body in a valve-closing direction through said plunger, and an electromagnetic actuator for magnetically attracting said plunger in a valve-opening direction against the urging force of said coiled spring, the improvement wherein: said valve body comprises a ball valve; and passageway means is provided for applying said control pressure to one end of said ball valve of said valve body in said valve-opening direction, and at the same time for applying said control pressure to another end of said ball valve of said valve body in said valve-closing direction.