초록 ▼

This refrigeration system expansion valve assembly (10) includes a valve body (12) having an upper portion (14) an intermediate portion (15) providing a valve chamber (17) and a valve port (18), and a lower portion (16). A valve inlet (20) and outlet (22) communicate with the valve chamber (17) on e

This refrigeration system expansion valve assembly (10) includes a valve body (12) having an upper portion (14) an intermediate portion (15) providing a valve chamber (17) and a valve port (18), and a lower portion (16). A valve inlet (20) and outlet (22) communicate with the valve chamber (17) on each side of the valve port (18). A piston assembly (24) is mounted in the body (12) for closing the valve port (18). The piston assembly (24) is actuated by a push rod assembly (26) driven by a stepper motor 28. The push rod assembly (26) includes a threaded member (102) slidingly and non-rotatively mounted in the body (12) and linearly driven by the motor shaft (30) which is threadedly received by said threaded member (102). The piston assembly (24) is urged into engagement with the push rod assembly (26) by a return spring (36) and includes a fluted nose portion (80) and a bleed passage (90, 92) communicating valve chamber (17) and the spring compartment (75).

대표청구항 ▼

An expansion valve comprising: (a) a hollow body including an upper portion, a lower portion and a valve chamber disposed between said upper and lower portions and including a valve port having seating means, (b) an inlet means communicating with the valve chamber on one side of the valve port and a

An expansion valve comprising: (a) a hollow body including an upper portion, a lower portion and a valve chamber disposed between said upper and lower portions and including a valve port having seating means, (b) an inlet means communicating with the valve chamber on one side of the valve port and an outlet means communicating with the valve chamber on the other side of the valve port, (c) piston means linearly movable in said body between a valve open and valve closed position, said piston means being operatively seated against said valve port seating means in the closed position, (d) push rod means including a threaded member mounted for linear movement in the body and operatively engageable with the piston means to induce linear movement into said piston means, said push rod means including stop means, (e) a stepper motor carried by the upper portion of the body and including a rotatable shaft means threadedly received by the threaded member of the push rod means, said rotatable shaft means including cooperating stop means engageable with the stop means of the push rod means to limit angular rotation of the rotatable shaft means whereby to precisely determine linear travel of the push rod means and the piston means, and (f) spring means carried by the lower portion of the body and operatively engageable with the piston means to urge the piston means into operative engagement with the push rod means.