Abstract: A fluid flow control device primarily intended for throttling the flow of liquid refrigerant between two flow rates. The device includes a disc which moves between two distinct positions with a snap action in response to changes in temperature of the refrigerant. The disc is connected at its center to a stem member having an axial bore aligned with and of smaller cross-sectional area than the outlet passage of a flow chamber wherein the disc and stem are positioned. When refrigerant temperature increases to a predetermined level, the disc moves the stem into contact with the chamber wall surrounding the outlet orifice, thereby limiting refrigerant flow to that which passes through the relatively smaller bore of the stem member. When refrigerant temperature drops sufficiently, the disc snaps back to the other position, moving the end of the stem away from the outlet orifice to permit flow at a higher rate.

Abstract: A flow metering device for installation in a liquid refrigerant line. A rotatable member is positioned in a flow passage between inlet and outlet ports within an enclosed chamber of the device. The member includes a portion having a plurality of orifices of different sizes having centers arranged on a circle concentrically surrounding the axis about which the member is rotatable to position a desired one of the orifices in the flow path. The enclosed chamber is accessible to permit physical rotation of the member by removal of a threaded cap normally covering an open side of the chamber. An O-ring seal prevents escape of pressurized refrigerant when the cap is removed. A check valve assembly may be included to accommodate flow of refrigerant in the opposite direction, as when used in heat pump applications where two of the devices would be employed, one with each of the indoor and outdoor coils.