US 5,702,235 AGranted

Capacity control device for valiable-capacity compressor

AssigneeTgk Co., Ltd.

InventorsHisatoshi Hirota, Naoyuki Ito

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Abstract

A capacity control device for variable-capacity compressors with a high-pressure valve portion 36 for opening or closing the communication between the discharge chamber 21 and the crank case 12; a low-pressure valve portion 41 for opening or closing the communication between the suction chamber 20 and the crank case 12; a valve open-close member 35 for opening or closing so as to reverse the open-close relationship between the high-pressure valve portion 36 and the low-pressure valve portion 41 by advancing or retreating; a pressurising chamber 53 for applying pressure to the valve open-close member 35 in a direction that opens the high-pressure valve portion 36 by a wider effective pressure-receiving area than that of the high-pressure valve portion 36. The device is driven with only small actuation forces by an electromagnetic solenoid 50 to open or close a communicating path between the discharge chamber 21 and the pressurising chamber 53 (FIG. 1).

Claims15

Dependent claims

A capacity control device for a variable-capacity compressor, said variable-capacity compressor having 1) a rocking member with an inclination angle that is variable with respect to a rotating shaft in an airtight crank case, the rocking member being driven by rotational motion of said rotating shaft for rocking motion, and 2) a piston, connected to said rocking member, for discharging a refrigerant into a discharge chamber after sucking the refrigerant from a suction chamber into a cylinder for compression by reciprocating, said capacity control device controlling the capacity of said variable-capacity compressor by varying the difference between a pressure in said crank case and a pressure in said suction chamber to vary the inclination angle of said rocking member and hence to change the discharge amount of refrigerant, said control device comprising:

a high-pressure valve portion for opening or closing a fluid communication path between said discharge chamber and said crank case, said high-pressure valve portion having an effective pressure-receiving area;
a low-pressure valve portion for opening or closing a fluid communication path between said suction chamber and said crank case;
a valve operating member coupled to said high-pressure valve portion and to said low-pressure valve portion and operable to reverse an open-close relationship between said high-pressure valve portion and said low-pressure valve portion by advancing or retreating;
a pressurising chamber for applying pressure to said valve operating member in a direction that opens said high-pressure valve portion, said pressurizing chamber having an effective pressure-receiving area that is larger than the effective pressure-receiving area of said high-pressure valve portion;
and a pilot valve portion having an effective pressure-receiving area that is smaller than said effective pressure-receiving area of said high-pressure valve portion;
and
an electromagnetic solenoid that drives said pilot valve portion to open or close a fluid communication path between said discharge chamber and said pressurising chamber.

4 more elements

A capacity control device for a variable-capacity compressor, said variable-capacity compressor comprising 1) an airtight crank case in fluid communication with a suction chamber and a discharge chamber, 2) a shaft rotatably mounted on said crank case, 3) a rocking member mounted on said shaft so as to have a variable inclination angle, and 4) a piston and cylinder device mounted on said rocking member and operable to suck refrigerant from said suction chamber and to discharge the refrigerant into said discharge chamber, said capacity control device controlling the capacity of said variable-capacity compressor by varying the difference between a pressure in said crank case and a pressure in said suction chamber to vary the inclination angle of said rocking member and hence to change the discharge amount of refrigerant, said capacity control device comprising:

(A) a high-pressure valve portion which is selectively actuatable to open or close a fluid communication path between said discharge chamber and said crank case, said high-pressure valve portion having an effective pressure receiving area;
(B) a low-pressure valve portion which is selectively actuatable to open or close a fluid communication path between said suction chamber and said crank case;
(C) a valve operating member which actuates said high-pressure valve portion and said low-pressure valve portion, said valve operating member being movable between (1) a first position in which said valve operating member causes said high-pressure valve portion to assume an open position and said low-pressure valve portion to assume a closed position and (2) a second position in which said valve operating member causes said high-pressure valve portion to assume a closed position and said low-pressure valve portion to assume an open position;
(D) a pressurizing chamber in fluid communication with said valve operating member, wherein fluid pressure in said pressurizing chamber tends to drive said valve operating member towards said first position, and wherein said pressurizing chamber has an effective pressure receiving area that is larger than the effective pressure receiving area of said high-pressure valve portion;
(E) a pilot valve portion which is selectively actuatable to open or close a fluid communication path between said discharge chamber and said pressurizing chamber, said pilot valve portion having an effective pressure receiving area that is smaller than the effective pressure receiving area of said high-pressure valve portion;
and
(F) an electromagnetic solenoid which actuates said pilot valve portion.

4 more elements

A refrigerant supply system comprising:

(A) a variable-capacity compressor, said variable-capacity compressor including
(1) an airtight crank case in fluid communication with a suction chamber and a discharge chamber,
(2) a shaft rotatably mounted on said crank case,
(3) a rocking member mounted on said shaft so as to have a variable inclination angle, and
(4) a piston and cylinder device mounted on said rocking member and operable to suck refrigerant from said suction chamber and to discharge the refrigerant into said discharge chamber;
and
(B) a capacity control device which controls the capacity of said variable-capacity compressor by varying the difference between a pressure in said crank case and a pressure in said suction chamber to vary the inclination angle of said rocking member and hence to change the discharge amount of refrigerant, said capacity control device including
(1) a high-pressure valve portion which is selectively actuatable to open or close a fluid communication path between said discharge chamber and said crank case, said high-pressure valve portion having an effective pressure receiving area,
(2) a low-pressure valve portion which is selectively actuatable to open or close a fluid communication path between said suction chamber and said crank case,
(3) a valve operating member which actuates said high-pressure valve portion and said low-pressure valve portion, said valve operating member being movable between (a) a first position in which said valve operating member causes said high-pressure valve portion to assume an open position and said low-pressure valve portion to assume a closed position and (b) a second position in which said valve operating member causes said high-pressure valve portion to assume a closed position and said low-pressure valve portion to assume an open position,
(4) a pressurizing chamber in fluid communication with said valve operating member, wherein fluid pressure in said pressurizing chamber tends to drive said valve operating member towards said first position, and wherein said pressurizing chamber has an effective pressure receiving area that is larger than the effective pressure receiving area of said high-pressure valve portion,
(5) a pilot valve portion which is selectively actuatable to open or close a fluid communication path between said discharge chamber and said pressurizing chamber, said pilot valve portion having an effective pressure receiving area that is smaller than the effective pressure receiving area of said high-pressure valve portion, and
(6) an electromagnetic solenoid which actuates said pilot valve portion.

10 more elements

Dependencies are inferred from the claim text.