An apparatus according to the present invention includes a support structure having a primary portion with first and second arm portions formed thereon for movement relative to one another, and a secondary portion with either a clamp portion or valve portion integrally formed on an outer end of each arm portion for movement therewith. A primary actuator is operably associated with the primary support structure for driving the arm portions relative to one another in response to an electrical activation of the primary actuator. Secondary actuators are operably associated with the secondary portions for independently driving the secondary portions between an opened position and a closed position in response to an electrical activation of each secondary actuator. Each of the actuators is operable independently of one another. The apparatus is operable to provide a bi-directional motor, a bi-directional pump, or a bi-directional compressor depending on the selected configuration and sequential mode of triggering the primary and secondary actuators.
CROSS-REFERENCE TO RELATED APPLICATIONS
This application is a continuation of Provisional Patent Application Ser. No. 60/390,620 filed Jun. 21, 2002, which is incorporated by reference herein.
The invention provides for a power steering assembly and method of actuation for assisting a driver in moving the steerable wheels of a vehicle. The power steering assembly includes a housing that defines a chamber. A steering rod is disposed in the chamber and is longitudinally moveable within the chamber. A shoulder is fixed to the steering rod and has opposing sides. A shaft is supported by the housing and engages the steering rod translating the rotational movement of the shaft into a longitudinal movement of the steering rod. A first actuator and second actuator are disposed in the chamber on opposing sides of the shoulder. The first and second actuators each have an excitable material that is controlled in a series of actuations to advance the actuators in a linear movement for pushing against the shoulder to move the steering rod longitudinally within the chamber.
An apparatus and process for pre-loading an electrically stimulated smart material actuator product to obtain maximum work from the actuator. When a smart material actuator is optimally pre-loaded certain desirable characteristics become apparent, such as work, operational frequency, hysteresis, repeatability, and overall accuracy. When used in conjunction with a mechanically leveraged actuator structure the smart material actuator can be used to its greatest potential. Since the mechanically leveraged actuator can be based on the maximum work provided by the smart material actuator, certain attributes such as the force, and displacement of total system can be adjusted without loss to system efficiency. Pre-loading methods and a determination of the optimal pre-load force are disclosed. Each smart material actuator type has a unique work curve. In the design of an actuator assembly, the process of optimizing uses the unique work curve to optimize the design for the requirements of the particular application. The unique work curve is used by finding the place where the smart material actuator is capable of providing the most work in order to set the optimum pre-load point accordingly. Different mechanical pre-load techniques are provided.
An apparatus and process for preloading an electrically stimulated smart material actuator product to obtain maximum work from the actuator. When a smart material actuator is optimally preloaded certain desirable characteristics become apparent, such as work, operational frequency, hysteresis, repeatability, and overall accuracy. When used in conjunction with a mechanically leveraged actuator structure the smart material actuator can be used to its greatest potential. Since the mechanically leveraged actuator can be based on the maximum work provided by the smart material actuator, certain attributes such as the force, and displacement of total system can be adjusted without loss to system efficiency. Preloading methods and a determination of the optimal preload force are disclosed. Each smart material actuator type has a unique work curve. In the design of an actuator assembly, the process of optimizing uses the unique work curve to optimize the design for the requirements of the particular application. The unique work curve is used by finding the place where the smart material actuator is capable of providing the most work in order to set the optimum preload point accordingly. Different mechanical preload techniques are provided.
