Abstract: A method and system of controlling the temperature of a refrigeration system. In an embodiment, an expansion valve for a refrigeration system comprises an entry portion, an exit portion, and a flow control portion including a piezo material. The entry portion is configured to allow refrigerant to flow into the expansion valve. The exit portion is configured to allow refrigerant to flow from the expansion valve. The flow control portion is disposed between the entry portion and the exit portion, and is configured to control a volume of refrigerant that passes through the expansion valve.
Type:
Grant
Filed:
January 17, 2006
Date of Patent:
August 9, 2011
Assignees:
Hussmann Corporation, Omega Piezo Technologies, Inc.
Inventors:
Ming Zhang, Sesha C. Madireddi, Byeongchul Na
Abstract: A tissue ablation apparatus is disclosed that includes an elongate, flexible device operable to be percutaneously place in vasculature of a patient. The device has an array of 8 or more tissue ablation elements carried on a flexible circuit substrate located at a distal end portion. A cable is also included that has a number of electrical conductors insulated from one another that are each electrically coupled to a different one of the elements. One or more connectors are electrically coupled to the cabling at a proximal end portion of the device.
Abstract: A crystal resonator having reduced acceleration sensitivity in which the resonator blank having one or more electrodes thereon has stiffening cover plates mounted to its top and bottom faces and spaced from the resonator blank by sidewalls.
Abstract: A crystal resonator device having a plurality of coupled resonators in which the relative phase and magnitude of the resonator excitation currents is controlled by electrical circuit means such as reactance components connected in series with one or more of the resonators to thereby minimize or otherwise control the acceleration sensitivity of the device.
Abstract: A resonator and resonator type wave filter formed by a piezoelectric body on which acoustic surface waves are guided and reflected and in which mode coupling in a direction transverse to the surface wave propagation is utilized. The transverse modes are controlled so as to provide improved response characteristics by minimizing suppressing and/or otherwise controlling unwanted modes of vibration in the body.
Type:
Grant
Filed:
May 19, 1976
Date of Patent:
November 29, 1977
Assignee:
Piezo Technology Inc.
Inventors:
Harry Frank Tiersten, Robert Chastain Smythe