Patent ID: 7373788

Claim:
An expansion valve comprising a valve body having a valve body hole extending substantially longitudinally therethrough, a first passage in communication with the valve body hole and formed in the valve body through which a high-pressure refrigerant passes, a bottomed valve chamber in communication with the valve body hole and formed in the first passage, a second passage in communication with the valve body hole and formed in parallel with the first passage in the valve body through which a refrigerant sent out to the evaporator side passes, a third passage in communication with the valve body hole and through which a refrigerant sent out from the evaporator side passes, and a guide member disposed in the valve body hole between the first passage and the third passage, wherein, in the guide member, a guide portion, which slidably guides an operation rod for opening and closing a valve element, and an orifice portion, which has a throttle portion for causing the valve chamber and the second passage to communicate with each other are formed integrally, a passage communicating with the second passage is formed between the guide portion and the orifice portion, the valve element is arranged so as to be opposed to the throttle portion, and the operation rod is driven by a driving device mounted on the valve body, the valve body hole has a first valve body hole portion having a first hole diameter and a second valve body hole portion having a second hole diameter smaller than the first hole diameter to form a valve body step, the valve body step disposed between the second passage and the third passage, and the guide has a first guide portion having a first guide portion diameter and a second guide portion having a second guide portion diameter being smaller than the first guide portion diameter to form a guide portion step, the guide sized to be slidably received by the valve body hole in a close-fitting relationship such that the first valve body hole portion receives the first guide portion, the second valve body hole portion receives the second guide portion and the valve body step and the guide portion step contact each other.