Active seal assemblies for movable windows

Abstract

Active seal assemblies employing active materials that can be controlled and remotely changed to alter the seal effectiveness, wherein the active seal assemblies actively change modulus properties such as stiffness, shape orientation, and the like. In this manner, in seal applications such as a vehicle window application, the seal force can be selectively reduced during movement of the window and increased when the window is stationary, thereby selectively changing seal effectiveness. Active materials refers to several different classes of materials all of which exhibit a change in at least one attribute such as dimension, shape, and/or flexural modulus when subjected to at least one of many different types of applied activation signals, examples of such signals being thermal, electrical, magnetic, stress, and the like.

1 . A vehicle window system, comprising: 
 a movable window slidably disposed within a stationary frame;    a seal assembly in sealing communication with the movable window, the seal assembly comprising a active material operative to change at least one attribute in response to an activation signal, wherein a seal force of the seal assembly against the window changes with a change in the at least one attribute of the active material;    an activation device in operative communication with the active material; and    a controller in operative communication with the activation device.    
     
     
         2 . The vehicle window system of  claim 1 , wherein the active material comprises a shape memory alloy, a shape memory polymer, a ferromagnetic shape memory alloy, an electroactive polymer, an electrorheological fluid, a magnetorheological elastomer, a dielectric elastomer, a magnetorheological fluid, piezoelectric material, an ionic polymer metal composite, or combinations comprising at least one of the foregoing materials.  
     
     
         3 . The vehicle window system of  claim 1 , wherein the active material forms an actuator, wherein the actuator is external to the seal assembly.  
     
     
         4 . The vehicle window system of  claim 1 , wherein the movable window is in operative communication with a motor.  
     
     
         5 . The vehicle window system of  claim 1 , wherein the movable window is in operative communication with a hand crank.  
     
     
         6 . The vehicle window system of  claim 1 , wherein the seal assembly comprises a plurality of strips and/or wires of the active material embedded within a seal structure.  
     
     
         7 . The vehicle window system of  claim 1 , wherein the seal assembly has a cross sectional area that selectively decreases or increases in response to the activation signal.  
     
     
         8 . The vehicle window system of  claim 1 , wherein the seal assembly comprises an exoskeleton formed of the active material and a seal membrane.  
     
     
         9 . The vehicle window system of  claim 1 , wherein the activation signal comprises a thermal activation signal, a magnetic activation signal, an electrical activation signal, chemical activation signal, or a combination comprising at least one of the foregoing signals.  
     
     
         10 . The vehicle window system of  claim 1 , wherein the seal assembly comprises the active material and a flexible seal structure.  
     
     
         11 . The vehicle window system of  claim 1 , wherein the seal assembly consists of the active material.  
     
     
         12 . The vehicle window system of  claim 1 , wherein the stationary frame is a door frame.  
     
     
         13 . The vehicle window system of  claim 1 , wherein the active material is in translational communication with a flexible seal structure abutting the movable window, wherein the change in the at least one attribute of the active material increases or decreases the seal force of the flexible seal structure against the movable window.  
     
     
         14 . A process for operating a vehicle window system, the process comprising: 
 disposing a seal assembly in sealing communication with a movable window, wherein the seal assembly comprises an active material operative to change at least one attribute in response to an activation signal, wherein a seal force of the seal assembly against the window changes with the change in the at least one attribute of the active material;    simultaneously moving the window and reducing the seal force by activating the active material; and    increasing the seal force when the window is stationary by discontinuing the activation signal to the active material.    
     
     
         15 . The process of  claim 14 , wherein the active material comprises a shape memory alloy, a shape memory polymer, a ferromagnetic shape memory alloy, an electroactive polymer, an electrorheological fluid, a magnetorheological elastomer, a dielectric elastomer, a magnetorheological fluid, piezoelectric material, an ionic polymer metal composite, or combinations comprising at least one of the foregoing materials.  
     
     
         16 . The process of  claim 14 , wherein the activation signal comprises a thermal activation signal, a magnetic activation signal, an electrical activation signal, chemical activation signal, or a combination comprising at least one of the foregoing signals.  
     
     
         17 . The process of  claim 14 , wherein the active material forms an actuator, wherein the actuator is external to the seal structure.  
     
     
         18 . The process of  claim 14 , wherein the seal assembly consists of the active material.  
     
     
         19 . The process of  claim 14 , wherein reducing the seal force comprises reducing a cross sectional area of the seal assembly.  
     
     
         20 . The process of  claim 14 , wherein the seal assembly comprises a plurality of strips and/or wires of the active material embedded within a seal structure.  
     
     
         21 . A vehicle window system, comprising: 
 a movable window slidably disposed within a stationary frame;    a seal assembly in sealing communication with the movable window, the seal assembly comprising a seal structure and an active fluid disposed within the seal structure, wherein the active fluid is operative to change at least one attribute in response to an activation signal, wherein a seal force of the seal assembly against the window changes with the change in the at least one attribute of the active material;    an activation device in operative communication with the active fluid; and    a controller in operative communication with the activation device.    
     
     
         22 . The vehicle window system of  claim 21 , wherein the active fluid comprises an electroactive gel, or a magnetorheological fluid.