摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion generally includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof. A selected one of the hook elements or the loop material is formed from a thermally and/or electrically conductive material. The other one is formed of a material adapted to melt, flow or volatize at a defined temperature. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. Introducing an activation signal to the thermally and/or electrically conductive hook elements or loop material, causes the opposing material to melt, flow, soften, or volatize upon contact therewith. Also disclosed herein are processes for operating the releasable fastener system.
摘要:
A releasable fastening system for retaining two surfaces at each other or disengaging the two surfaces from each other comprises a first electrode disposed at a first surface, a second electrode disposed at a second surface, and a polymer film disposed between the first and second electrode, and an electrolyte disposed in electrical communication with the first electrode, the polymer film, and the second electrode. A volume of the polymer film is controllably variable to cause the retention of the first surface at the second surface. A method of releasably fastening adjacently-positioned surfaces comprises disposing a first electrode at a first surface, disposing a second electrode at a second surface, and increasing the volume of an electrolyte disposed in electrical communication with the first electrode and the second electrode to cause the retention of the first surface at the second surface.
摘要:
Processes for providing rapid release of a hook and loop type releasable fastener system comprise preconditioning the releasable fastener system to effect rapid release. In this manner, minimal energy and time is required for disengagement of the releasable fastener system.
摘要:
A releasable fastening system comprises a knob portion comprising a knob element, a cavity portion comprising a cavity configured to receive the knob element, and an ionic polymer metal composite actuator disposed at the knob element. The ionic polymer metal composite actuator is operable to mechanically interlock the knob element with the cavity. A method of operating a releasable fastening system comprises contacting a knob portion with a cavity portion to form a releasable engagement, wherein the knob portion comprises a knob element disposed on a first support, and wherein the cavity portion comprises a cavity disposed at a second support; maintaining constant shear forces and constant pull-off forces between the knob portion and the cavity portion; and activating an ionic polymer metal composite actuator at the knob portion to facilitate the interlocking of the knob portion and the cavity portion.
摘要:
A releasable fastener system comprises a male portion and a female portion. The male portion comprises a support and at least one protrusion element fixedly attached to the support. The female portion comprises a support and at least two parallel actuator strips projecting from a surface of the support. The at least two parallel actuator strips are spaced apart to form an opening equal to or less than a lateral dimension of the protrusion element. Each one of the at least two parallel actuator strips comprise a flexible strip and a piezoelectric material disposed on portions of the actuator strip. An activation device is coupled to the at least two actuator strips, the activation device being operable to selectively provide an activation signal to the piezoelectric material. In this manner, the shape of the actuator strips can be changed to provide a mechanical engagement of a frictional engagement of the male and female portions.
摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion generally includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof, wherein the plurality of hook elements comprises or incorporates a shape memory polymer. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. Introducing a thermal activation signal to the plurality of hook elements causes a change in shape orientation and/or flexural modulus that effectively reduces the shear and/or pull off forces in the releasable engagement. In this manner, disengagement of the releasable fastener system provides separation of the hook portion from the loop portion under controlled conditions. Also disclosed herein are processes for operating the releasable fastener system.
摘要:
A releasable fastener system comprises a loop portion and a hook portion. The loop portion includes a support and a loop material disposed on one side thereof. The hook portion generally includes a support and a plurality of closely spaced upstanding hook elements extending from one side thereof, wherein the plurality of hook elements comprises or incorporates a shape memory alloy fiber. When the hook portion and loop portion are pressed together they interlock to form a releasable engagement. The resulting joint created by the engagement is relatively resistant to shear and pull forces and weak in peel strength forces. Introducing a thermal activation signal to the plurality of hook elements causes a change in shape orientation, flexural modulus property, or a combination thereof that effectively reduces the shear and/or pull off forces in the releasable engagement. In this manner, disengagement of the releasable fastener system provides separation of the hook portion from the loop portion under controlled conditions. Also disclosed herein are processes for operating the releasable fastener system.
摘要:
A system for controlling fluid flow about a vehicle. The system comprises a fluid flow control device, an obstacle sensor for detecting obstacles, and a controller. The fluid flow control device has a body with at least one surface and an actuation means in operative communication with the surface. The actuation means is operative to alter at least one attribute of the fluid flow control device in response to a control signal. The controller has control logic for generating the control signal in response to the obstacle sensor.
摘要:
An apparatus may have a multilayered support base having a structural section made up of operating components and a function support section. The function support section may have transmission paths and components to supply thermal, power transmission, information and communication paths, along with other functions. At least some of the components may be heat generating and may have a thermal interface surface which may be in operating and heat conductive relationship with a heat conductive substrate/routing section which may have operative connections to the multilayered support base. Some of the components may transmit and receive with one another through the substrate/routing section.
摘要:
A flow control valve for a fuel cell that has particular application for controlling the flow of cathode air through a cathode flow channel of the fuel cell. The valve includes an element that controls the flow through the flow channel in response to changes in the voltage potential of the fuel cell. The valve includes a shape memory alloy wire and a flow control element secured to both ends of the shape memory alloy wire. The ends of the wire are also coupled to the anode and cathode of the fuel cell. When no current is flowing through the wire, the flow control element holds the wire in a pre-strained condition. If the voltage generated by the fuel cell increases, the current passing through the wire will heat the wire and cause it to shrink or contract which forces the flow control element into the flow path.