Abstract: A position control system is used for controlling a fluid operated cylinder having at least one fluid chamber defined by a piston located within a housing for movement between first and second end limits of travel. The system includes at least two electrically actuated proportional flow control valves connected to each port of the cylinder for selectively and proportionally controlling fluid flow into and out of the at least one chamber. At least one pressure sensor is provided for measuring fluid pressure with respect to each chamber. At least one discreet position sensor is located adjacent a midpoint of the cylinder for sensing a discreet centered position of the piston. A controller includes a program and is operably connected for controlling actuation of the at least two valves in response to pressure measured by the at least one pressure sensor and location measured by the at least one position sensor.

Abstract: An apparatus using electrically-stimulated smart material requires a power source to stimulate the material. This power source has three main functions, (1) to apply a known voltage potential across the smart material, (2) to convert from the control voltage to a level suitable for the smart material, and (3) to regulate the voltage based on a control input. The power source is a DC to DC converter with special properties achieved by supplying a variable stimulating voltage or actively discharging the actuator. The circuit also provides a dead band, or hysteresis, between the charge point and discharge point. When this circuit is applied with a proportional, mechanically-leveraged smart material actuator, a general-purpose industrial actuator becomes a cost-effective solution.

Abstract: An apparatus having a smart material actuator, a support structure and at least one temperature compensating material insert, either externally mounted to the support structure, integrally formed with the support structure, or any combination thereof. The apparatus includes a mechanically leveraged electrically stimulated smart material. The support structure and actuator are susceptible to the effects of differences in thermal coefficients of expansion of the materials used in the construction. The smart material typically displaces less than 0.001 inches and is leveraged up to fifty times to obtain useful movement. The temperature effect on the smart material is therefore leveraged and amplified producing undesirable motion in the apparatus with ambient and/or operating temperature changes. A method for dimensioning and placement of a compensating insert with respect to the support structure provides an accurate and cost effective compensating insert.

Abstract: The present invention includes a method of compensating for differences in the rate of thermal expansion in one or more elements of an electro-mechanical actuator. The electro-mechanical actuator can include one or more elements such as a piezoelectric ceramic multilayer actuator (CMA) and a mechanism to amplify the motion of the CMA. A difference in the rate of thermal expansion or coefficient of thermal expansion, CTE, between the materials in the CMA and the amplifying mechanism can cause the two components to vary in size at differing rates as the ambient temperature varies. Since the amplifying mechanism provides substantial amplification of the motion of the CMA, the relative variation in size of the components due to temperature can be translated by the amplifying mechanism as motion of the CMA. This can result in substantial motion of the amplifying mechanism.

Abstract: An apparatus controls flow of a fluid from at least one inlet port to at least one outlet port. A support has a rigid, non-flexible portion, at least one pivotable relatively rigid, non-flexible, folded-back arm portion extending from the rigid portion, at least one surface connected to folded-back arm portion for movement relative to the support, and a rigid, non-flexible force transfer member operably positioned for driving the pivotable folded-back arm portion with a loss of motion of less than 40%. An electrically operated actuator operably engages between the rigid portion and the force transfer member to pivot the folded-back arm portion in response to an electrical activation of the actuator. A manifold includes a fluid passage communicating with at least one valve seat and operably engageable with respect to at least one corresponding valve body for movement between a closed position and an opened position.

Abstract: A position control system is used for controlling a fluid operated cylinder having at least one fluid chamber defined by a piston located within a housing for movement between first and second end limits of travel. The system includes at least two electrically actuated proportional flow control valves connected to each port of the cylinder for selectively and proportionally controlling fluid flow into and out of the at least one chamber. At least one pressure sensor is provided for measuring fluid pressure with respect to each chamber. At least one discrete position sensor is located adjacent a midpoint of the cylinder for sensing a discrete centered position of the piston. A controller includes a program and is operably connected for controlling actuation of the at least two valves in response to pressure measured by the at least one pressure sensor and location measured by the at least one position sensor.

Abstract: An apparatus for electrically stimulating a smart material includes a controllable power source for charging the smart material and/or switching circuitry for discharging the smart material. The controllable power source includes a regulated DC to DC converter having controllable drive circuitry associated therewith. The drive circuitry can be self-oscillating through associated feedback means. The switching circuitry can be responsive to one or more control signals.

Abstract: An apparatus for moving a pair of opposing surfaces in response to an electrical activation having a support including a rigid non-flexing portion, at least one pivotable arm portion extending from the rigid non-flexing portion, a pair of opposing surfaces with one opposing surface on the at least one pivotable arm portion for movement relative to one another, and a force transfer member operably positioned for driving the at least one pivotable arm portion in rotational movement. An actuator is operably engaged between the rigid portion and the force transfer member to drive the force transfer member in movement relative to the rigid portion to pivot the at least one pivotable arm portion with a loss of motion of less than 40% in response to an electrical activation of the actuator.

Abstract: 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.

Abstract: An apparatus for moving a pair of opposing surfaces in response to an electrical activation having a support including a rigid non-flexing portion, at least one pivotable arm portion extending from the rigid non-flexing portion, a pair of opposing surfaces with one opposing surface on the at least one pivotable arm portion for movement relative to one another, and a force transfer member operably positioned for driving the at least one pivotable arm portion in rotational movement. An actuator is operably engaged between the rigid portion and the force transfer member to drive the force transfer member in movement relative to the rigid portion to pivot the at least one pivotable arm portion with a loss of motion of less than 40% in response to an electrical activation of the actuator.

Abstract: An apparatus for moving a pair of opposing surfaces in response to an electrical activation having a support including a rigid non-flexing portion, at least one pivotable arm portion extending from the rigid non-flexing portion, a pair of opposing surfaces with one opposing surface on the at least one pivotable arm portion for movement relative to one another, and a force transfer member operably positioned for driving the at least one pivotable arm portion in rotational movement. An actuator is operably engaged between the rigid portion and the force transfer member to drive the force transfer member in movement relative to the rigid portion to pivot the at least one pivotable arm portion with a loss of motion of less than 40% in response to an electrical activation of the actuator.

Abstract: The present invention provides an apparatus for moving a member including a first clamp assembled to a fixed surface for selectively clamping the member and a second clamp moveable with respect to the first clamp for selectively clamping the member. A piezo actuator is disposed between the first and second clamps for moving the member in response to expansion of the actuator. Resilient means bias the second clamp toward the first clamp.

Abstract: A pizoelectric actuator assembly for actuating industrial control valves or clamps provides a compact actuator including a single piece main structure with integrated hinge, mechanical lever, and spring in a shape such that in response to electrical activation, the piezoelectric device transfers mechanical energy from a predetermined axis into the force transfer member operably positioned for driving at least one pivotable arm portion in rotational movement with a loss of motion of less than 40%.

Abstract: The present invention provides an apparatus having at least one pair of opposing surfaces formed on a support structure for movement relative to one another and an actuator operably engaging the support structure for driving the at least one pair of opposing surfaces relative to one another in response to an electrical activation of the actuator. Preferably, the actuator is a piezoelectric device. The apparatus can be adapted for clamping and/or valving applications.