Damped drivable assembly, and method for damping drivable assembly

Abstract

A damped assembly is provided including a drivable assembly with housing, and a damper structure in operative association with the housing for dampening noise and/or vibration. The damper structure includes a viscoelastic damper layer and a continuous, polymeric constraining layer intimately contacting and encasing the viscoelastic damper layer.

1 . A damped assembly comprising:
 a drivable assembly;   a housing forming a chamber in which at least a portion of the drivable assembly is housed; and   a damper structure operatively associated with the housing for dampening noise and/or vibration, the damper structure comprising
 a viscoelastic damper layer; and 
 a continuous, polymeric constraining layer intimately contacting and encasing the viscoelastic damper layer, the constraining layer being molded from a high density filler and a moldable compound that is immiscible with the viscoelastic damper layer to provide a discrete interface between the constraining layer and the viscoelastic damper layer. 
   
   
   
       2 . A damped assembly according to  claim 1 , wherein the constraining layer had a greater stiffness and higher modulus of dynamic shearing elasticity than the viscoelastic damper layer. 
   
   
       3 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer comprises a polymeric reaction product of a composition comprising a member selected from the group consisting of (meth)acrylic acid and (meth)acrylate. 
   
   
       4 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer comprises a polyacrylate. 
   
   
       5 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer comprises a member selected from the group consisting of nitrile rubbers and fluoroelastomers. 
   
   
       6 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer is free of fillers. 
   
   
       7 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer comprises a plurality of fragments that are noncontinuous with each other to provide interstices between the noncontinuous fragments. 
   
   
       8 . A damped assembly according to  claim 1 , wherein the viscoelastic damper layer is continuous and non-fragmented. 
   
   
       9 . A damped assembly according to  claim 1 , wherein the continuous constraining layer further comprises high density filler comprising a member selected from the group consisting of glass, carbon, aramids, metal, plastics, alumina, silica, silicon, ceramic, and graphite. 
   
   
       10 . A damped assembly according to  claim 1 , wherein the constraining layer further comprises chopped fiberglass. 
   
   
       11 . A damped assembly according to  claim 2 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least two orders of magnitude greater than that of the viscoelastic damper layer. 
   
   
       12 . A damped assembly according to  claim 2 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least three orders of magnitude greater than that of the viscoelastic damper layer. 
   
   
       13 . A damped assembly according to  claim 2 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least about 500,000 psi. 
   
   
       14 . A damped assembly according to  claim 2 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least about 1,000,000 psi. 
   
   
       15 . A damped assembly according to  claim 1 , wherein the constraining layer comprises a member selected from the group consisting of epoxy, polyurethane, polyester, acetal, polystyrene, acrylonitrile-butadiene-styrene, and polyvinylchloride. 
   
   
       16 . A damped assembly according to  claim 1 , wherein the constraining layer comprises a polyester. 
   
   
       17 . A damped assembly according to  claim 1 , wherein the damper structure is in intimate contact with an outer surface of the housing. 
   
   
       18 . A damped assembly according to  claim 1 , wherein the damper structure is in intimate contact with an inner surface of the housing. 
   
   
       19 . A damped assembly comprising:
 a drivable assembly;   a housing forming a chamber in which at least a portion of the drivable assembly is housed; and   a damper structure operatively associated with the housing for dampening noise and/or vibration, the damper structure comprising
 a viscoelastic damper layer; and 
 a continuous, polymeric constraining layer intimately contacting the viscoelastic damper layer and molded from a high density filler and a melt-flowable polymer matrix that is immiscible with the viscoelastic damper layer to provide a discrete interface between the constraining layer and the viscoelastic damper layer. 
   
   
   
       20 . A damped assembly according to  claim 19 , wherein the constraining layer has a greater stiffness than the viscoelastic damper layer, a modulus of dynamic shearing elasticity of at least 500,000 psi and higher than the viscoelastic damper layer, and a density of at least 3.0 grams per cubic centimeter. 
   
   
       21 . A damped assembly according to  claim 19 , wherein the viscoelastic damper layer comprises a polymeric reaction product of a composition comprising a member selected from the group consisting of (meth)acrylic acid and (meth)acrylate. 
   
   
       22 . A damped assembly according to  claim 19 , wherein the viscoelastic damper layer comprises a polyacrylate. 
   
   
       23 . A damped assembly according to  claim 19 , wherein the viscoelastic damper layer comprises a member selected from the group consisting of nitrile rubbers and fluoroelastomers. 
   
   
       24 . A damped assembly according to  claim 19 , wherein the viscoelastic damper layer is free of fillers. 
   
   
       25 . A damped assembly according to  claim 19 , wherein the viscoelastic damper layer comprises a plurality of fragments that are noncontinuous with each other to provide interstices between the noncontinuous fragments. 
   
   
       26 . A damped assembly according to  claim 19 , wherein the constraining layer further comprises high density filler comprising a member selected from the group consisting of glass, carbon, aramids, metal, plastics, alumina, silica, silicon, ceramic, and graphite. 
   
   
       27 . A damped assembly according to  claim 19 , wherein the constraining layer further comprises chopped fiberglass. 
   
   
       28 . A damped assembly according to  claim 20 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least two orders of magnitude greater than that of the viscoelastic damper layer. 
   
   
       29 . A damped assembly according to  claim 20 , wherein the modulus of dynamic shearing elasticity of the constraining layer is at least three orders of magnitude greater than that of the viscoelastic damper layer. 
   
   
       30 . A damped assembly according to  claim 19 , wherein the constraining layer comprises a member selected from the group consisting of epoxy, polyurethane, polyester, acetal, polystyrene, acrylonitrile-butadiene-styrene, and polyvinylchloride. 
   
   
       31 . A damped assembly according to  claim 19 , wherein the constraining layer comprises a polyester. 
   
   
       32 . A damped assembly according to  claim 19 , wherein the density of the constraining layer is at least 5.0 grams per cubic centimeter. 
   
   
       33 . A damped assembly according to  claim 19 , wherein the damper structure is in intimate contact with an outer surface of the housing. 
   
   
       34 . A damped assembly according to  claim 19 , wherein the damper structure is in intimate contact with an inner surface of the housing. 
   
   
       35 - 67 . (canceled)