Abstract:
A shock mount device for a container includes a variable spring rate assembly coupled to a shock retainer. The variable spring rate assembly is removable from the shock retainer without removing equipment from the container. The variable spring rate assembly includes a replaceable core that may be exchanged with a replaceable core having either a larger or smaller durometer depending on a weight-to-load ration of equipment in the container. Removing and replacing the replaceable core may include removing and replacing the entire variable spring rate assembly.

Description:
BACKGROUND OF THE INVENTION 
       [0001]    Various types of containers for moving equipment, such as electronics equipment or other types of delicate devices and systems, been employed in military and commercial environments. Because the containers may be moved fairly often during transit, for example on ships, trucks, airplanes and other vehicles, the containers may be subjected to a variety of impact conditions, vibration, and other types of forces and accelerations over their operational life. To support and protect the equipment within the container, conventional shock mount devices with non-adjustable weight-to-load ratios are employed to isolate the equipment within the container and to absorb the inertial loading caused by one or more of the above-described load conditions. 
       SUMMARY OF THE INVENTION 
       [0002]    A shock mount device for a container includes a variable spring rate assembly coupled to a shock retainer. The variable spring rate assembly is removable from the shock retainer without removing equipment from the container. The variable spring rate assembly includes a replaceable core that may be exchanged with a replaceable core having either a larger or smaller durometer depending on a weight-to-load ration of equipment in the container. Removing and replacing the replaceable core may include removing and replacing the entire variable spring rate assembly. 
         [0003]    In one example of the invention, a shock mount device for a container includes a shock retainer having a receiving end portion attached to a wall of the container and a closed end portion located distally from the receiving end portion, the shock retainer having an inner surface defining a cavity; and a variable spring rate assembly having a replaceable core receivable within the cavity of the shock retainer, the replaceable core coupled to a coupling member configured to secure the replaceable core to the shock retainer. 
         [0004]    In another example of the invention, a shock mount device for a container includes a shock retainer having a receiving end portion coupled to a wall of the container and a closed end portion located distally from the receiving end portion, the shock retainer having an inner surface defining a cavity and further having first and second engagement portions, the first engagement portion located proximate the closed end portion, the second engagement portion located proximate the receiving end portion; and a variable spring rate assembly insertable into the shock retainer, the variable spring rate assembly having a replaceable core located between a first end cap and a second end cap, the variable spring rate assembly engageable with the shock retainer. 
         [0005]    In yet another example of the invention, a method for changing a stiffness of a shock mount device for a container includes the steps of (1) removing a variable spring rate assembly from a shock retainer coupled to a wall of the container; and (2) changing a first replaceable core of the variable spring rate assembly with a second replaceable core, the first replaceable core having a spring rate that is different than a spring rate of the second replaceable core. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0006]    In the drawings, identical reference numbers identify similar elements or acts. The sizes and relative positions of elements in the drawings may not be necessarily drawn to scale. For example, the shapes of various elements and angles may not be drawn to scale, and some of these elements may be arbitrarily enlarged or positioned to improve drawing legibility. 
           [0007]    The preferred and alternative embodiments of the present invention are described in detail below with reference to the following drawings. 
           [0008]      FIG. 1  is an isometric, partially exploded, cross-sectional view of a shock mount device having a shock retainer and a variable spring rate assembly coupled to a wall of a container according to an embodiment of the present invention; 
           [0009]      FIG. 2  is a side elevational view of the variable spring rate assembly of  FIG. 1  coupled to the wall; 
           [0010]      FIG. 3  is a cross-sectional view of the variable spring rate assembly of  FIG. 1  taken along line  3 - 3  of  FIG. 2 ; 
           [0011]      FIG. 4  is a side elevational view of the shock retainer of  FIG. 1  coupled to the wall; and 
           [0012]      FIG. 5  is a cross-sectional view of the shock retainer of  FIG. 1  taken along line  5 - 5  of  FIG. 4 . 
       
    
    
     DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT 
       [0013]    In the following description, certain specific details are set forth in order to provide a thorough understanding of various embodiments of the invention. However, one skilled in the art will understand that the invention may be practiced without these details. In other instances, well-known structures associated with equipment containers, shock mount devices with insertable cores and methods of assembling the same have not necessarily been shown or described in detail to avoid unnecessarily obscuring descriptions of the embodiments of the invention. 
         [0014]    In addition, throughout the specification and claims which follow, the term “container” is meant as a broad term that includes a variety of structures having an interior space sized to receive a variety of items, such as, but not limited to, electronics, optical, or other equipment that may be otherwise susceptible to damage if not properly packaged in the container. Further, the term “container” as used herein generally may include structurally rigid containers that may be stacked together. 
         [0015]      FIG. 1  shows a shock mount device  100  coupled to a wall  102  of a container (not shown). The shock mount device  100  allows adjustment of a weight-to-load ratio without removing equipment from the container. The shock mount device  100  includes a shock retainer  104  and a variable spring rate assembly  106 . The shock retainer  104  is coupled to the wall  102  and the variable spring rate assembly  106  is received in the shock retainer  104 . The variable spring rate assembly  106  includes a replaceable core  108  coupled to a coupling member  110 . The shock retainer  104  includes a receiving end portion  112  distally located from a closed end portion  114  and an inner surface  116  of the shock retainer  104  defines a cavity  118  for receiving at least a portion of the variable spring rate assembly  106 . By way of example, when the variable spring rate assembly  106  is received in the shock retainer  104  the coupling member  110  may be threaded into the receiving end portion  112 . The coupling member  110  may also take the form of a coupling end cap for securing the variable spring rate assembly  106  and attaching it to the shock retainer  104 . 
         [0016]    In one embodiment, the shock retainer  104  further includes a first engagement portion  120  and a second engagement portion  122 . The first engagement portion  120  may be configured to threadably engage a first end cap  124  of the variable spring rate assembly  106  while the second engagement portion  122  may be configured to threadably engage a second end cap  126  of the variable spring rate assembly  106 . In addition, the shock retainer may include a shock retainer end cap  128  coupled to the closed end portion  114 . 
         [0017]      FIGS. 2 and 3  show the variable spring rate assembly  106 . Specifically,  FIG. 2  shows the variable spring rate assembly  106  coupled to the wall  102 . Now referring to  FIG. 3 , the replaceable core  108  is sandwiched between the first and second end caps  124 ,  126 . The first end cap  124  includes a threaded protuberance  130  for threadably engaging the first engagement portion  120  ( FIG. 1 ) of the shock mount retainer  104  ( FIG. 1 ). The second end cap  126  includes a threaded bore  132  configured for threadably engaging a threaded portion  134  of the coupling member  110 . A sealing member  136 , such as an o-ring seal, may be placed in a recess  138  of the coupling member  110 . The replaceable core  108  may be an elastomeric core having an appropriate size to be received between the end caps  124 ,  126  and further be received into the shock retainer  104 . The replaceable core  108  may have a selected durometer to meet a predetermined weight-to-load ratio of the equipment in the container. If equipment is added or removed or if the loading on the container is expected to be different, the replaceable core  108  may be removed and replaced with another replaceable core  108  having a different durometer without removing the equipment from the container. 
         [0018]    Briefly referring back to  FIG. 1 , the variable spring rate assembly  106  may be de-coupled or otherwise unscrewed from the shock retainer  104 . Then the coupling member  110  and end caps  124 ,  126  may be removed and a new, replaceable core  108  inserted between the end caps  124 ,  126 . In another embodiment, an inventory of variable spring rate assemblies  106  may be available such that the entire variable spring rate assembly  106  may be simply removed and replaced to achieve a shock mount device  100  having different shock absorbent characteristics. Thus, the replaceable core  108  or the variable spring rate assembly  106  in its entirety may be changed based the weight of equipment placed in the container. 
         [0019]      FIGS. 4 and 5  show the shock retainer  104  coupled to the wall  102  of the container (not shown). For purposed of clarity, it is understood that the shock retainer  104  extends into the container while the variable spring rate assembly  106  is accessible from outside of the container. In one embodiment, a wall  140  of the shock retainer  104  is made from an elastomeric material having a selected durometer. The elastomeric material forming the wall  140  may have the same durometer as the replaceable core  108  or may have a significantly different durometer. The cavity  118  formed by the inner surface  116  of the wall  140  is configured to receive replaceable cores  108  having a variety of durometers (e.g., spring rates). 
         [0020]    While the preferred embodiment of the invention has been illustrated and described, as noted above, many changes can be made without departing from the spirit and scope of the invention. Accordingly, the scope of the invention is not limited by the disclosure of the preferred embodiment. Instead, the invention should be determined entirely by reference to the claims that follow.