Energy absorber for counterbalance mechanism

Abstract

An energy-absorbing device for use with a counterbalance mechanism to relatively harmlessly absorb energy potentially released should a component of the counterbalance mechanism fail. A frame is attached to a portion of the counterbalance mechanism and supports an impact receiving member, and a plurality of deformable support members. In the event of a failure in the counterbalance mechanism, a part of the counterbalance mechanism strikes a face of the impact receiving member. Deformable support members are attached to the opposing face of the impact receiving member and are deformed by the impact and thus absorb the energy that is transferred by the impact. The deformable support members and the impact receiving member are readily replaceable.

1 . An energy-absorbing device for use in connection with a counterbalance apparatus, comprising:
 (a) a base;   (b) an impact receiving member having a first face and an opposite second face, the impact receiving member being supported in a location adjacent the base; and   (c) a deformable support member attached to the impact member and interconnected with the base, the deformable support member being arranged to be deformed by an impact on the first face and thus to absorb energy from an impact on the first face of the impact receiving member.   
   
   
       2 . The energy-absorbing device of  claim 1 , wherein the deformable support member is plastically deformed when absorbing the energy from the impact. 
   
   
       3 . The energy-absorbing device of  claim 1 , wherein the base includes a collar defining an interior space and the impact receiving member is held within the interior space by the deformable support member prior to receiving an impact. 
   
   
       4 . The energy-absorbing device of  claim 1 , wherein the deformable support member is U-shaped. 
   
   
       5 . The energy-absorbing device of  claim 1 , including a plurality of the deformable support members, attached to the impact receiving member at apart-spaced positions. 
   
   
       6 . The energy-absorbing device of  claim 1 , including a plurality of the deformable support members, each detachably attached to the base. 
   
   
       7 . The energy-absorbing device of  claim 1 , wherein the deformable support member is fixedly attached to the impact receiving member. 
   
   
       8 . The energy-absorbing device of  claim 1 , wherein the counterbalance apparatus includes a spring and a cable arranged to load the spring, and wherein the impact receiving member is located in a probable path of the spring should the cable fail under load. 
   
   
       9 . A counterbalance apparatus, comprising:
 (a) a force-generating element and a tension-carrying member, the force-generating element being interconnected with the tension-carrying member;   (b) a guide tube that at least partially surrounds a portion of the force-generating element and the tension-carrying member;   (c) a collar mounted on an end of the guide tube;   (d) an impact receiving member mounted adjacent the end of the guide tube, and having a first face directed toward the force-generating element and having an opposite second face; and   (e) a deformable support member attached to the second face of the impact receiving member and interconnected with the collar, the deformable support member being arranged to absorb energy from and thus to be deformed by an impact of the force-generating element against the first face of said impact receiving member and thereby avoid damage to other portions of the counterbalance apparatus in event of a failure of the tension-bearing member.   
   
   
       10 . The counterbalance apparatus of  claim 9  including a plurality of the deformable support members, wherein the impact receiving member and the deformable support members are interconnected with the collar by fasteners whereby the deformable support members are replaceable.