Patent Publication Number: US-2013233760-A1

Title: Shock and vibration dampening device

Description:
RELATED APPLICATIONS 
     This application claims the benefit of U.S. Provisional Application No. 61/532,815, filed Sep. 9, 2011, and which is incorporated herein by reference. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to storage and shipping containers, and more particularly to shock and vibration dampening devices for such containers. 
     BACKGROUND OF THE INVENTION 
     Fragile articles require special packaging when stored and/or shipped inside shipping containers. Conventional container packaging used to protect such articles includes paper, nuggets of expanded foam, preformed polystyrene foam or beads, etc. Ideally, the packaging absorbs and dissipates shocks and vibrations impinging the shipping container to minimize the shocks and vibrations experienced by the fragile article&#39;s). 
     Conventional container packaging materials have proved inadequate to meet the more stringent shock and vibration absorption requirements for modem articles of commerce. In order to satisfy such requirements, large volumes of conventional container packaging is required around the article. Voluminous packaging materials are expensive and take up excessive warehouse space before use and trash/recycling space after use. Further, larger shipping containers are necessitated by the voluminous container packaging, which are more expensive to purchase and to ship. The shock/vibration dissipation performance of paper, nugget and bead packaging materials can depend in large part on how the user actually packages the particular article(s). If a particular conventional container packaging is deemed to provide inadequate shock/vibration protection, there is no predictable way to modify such packaging material to meet such shock/vibration dissipation requirements, except for adding more packaging material and increasing the shipping container size. 
     More recently, unitary packaging structures have been developed that are made of flexible polymeric materials to allow shocks to dissipate through flexing of the structure walls. Examples of such unitary structures can be found in U.S. Pat. Nos. 5,226,543, 5,385,232, 5,515,976, and 5,799,796. However, these solutions must be custom made for each fragile article. Moreover, all these solutions fail to protect shipping containers from external shocks and vibrations, and instead attempt to absorb such shocks/vibrations inside the shipping container. Lastly, many fragile articles are shipped or stored on pallets, which lack walls to contain packaging materials. 
     There is a need for a dampening device that protects storage and/or shipping containers, pallets, etc. from shocks and vibrations using minimal storage space before and after use, and which uses minimal packaging material to reduce cost and shipping weight. 
     BRIEF SUMMARY OF THE INVENTION 
     A dampening device includes opposing top and bottom walls, an annular inner side wall extending between the top and bottom walls, and an annular outer side wall extending between the top and bottom walls and around the annular inner side wall wherein at least one portion of the outer side wall has an outwardly protruding convex cross sectional shape. The inner and outer side walls are formed of a resilient material that flexes as the top and bottom walls are compressed toward each other. 
     A dampening assembly includes a bracket having a first member extending in a first plane, a second member extending in a second plane, and a third member extending in a third plane. The second and third members are connected to or extend from the first member, and the first, second and third planes are orthogonal to each other. First, second and third dampening devices are mounted to the first, second and third members, respectively. Each of the first, second and third dampening devices includes opposing top and bottom walls, an annular inner side wall extending between the top and bottom walls, and an annular outer side wall extending between the top and bottom walls and around the annular inner side wall. At least one portion of the outer side wall has an outwardly protruding convex cross sectional shape. The inner and outer side walls are formed of a resilient material that flexes as the top and bottom walls are compressed toward each other. 
     A dampening device includes opposing top and bottom walls, a coil spring extending between the top and bottom walls, and an annular outer side wall extending between the top and bottom walls and around the coil spring, wherein at least a portion of the outer side wall has an outwardly protruding convex cross sectional shape. The outer side wall is formed of a resilient material that flexes as the top and bottom walls are compressed toward each other. 
     Other objects and features of the present invention will become apparent by a review of the specification, claims and appended figures. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a side cross section view of an embodiment of the dampening device. 
         FIG. 2  is a side cross section view of an embodiment of the dampening device. 
         FIG. 3  is a side cross section view of an embodiment of the dampening device. 
         FIG. 4  is a side cross section view of an embodiment of the dampening device. 
         FIG. 5  is a side cross section view of an embodiment of the dampening device. 
         FIG. 6  is a side cross section view of an embodiment of the dampening device. 
         FIG. 7  is a side cross section view of an embodiment of the dampening device. 
         FIG. 8  is a side cross section view of an embodiment of the dampening device. 
         FIG. 9  is a side cross section view of an embodiment of the dampening device. 
         FIG. 10  is a side cross section view of an embodiment of the dampening device. 
         FIG. 11  is a side cross section view of art embodiment of the dampening device. 
         FIG. 12  is a side cross section view of an embodiment of the dampening device. 
         FIG. 13  is a side cross section view of an embodiment of the dampening device. 
         FIG. 14  is a side cross section view of an embodiment of the dampening device. 
         FIG. 15  is a side cross section view of an embodiment of the dampening device. 
         FIG. 16  is a side cross section view of an embodiment of the damp device. 
         FIG. 17  is a side cross section view of an embodiment of the dampening device. 
         FIG. 18  is a side cross section view of an embodiment of the dampening device. 
         FIG. 19  is a side cross section view of an embodiment of the dampening device. 
         FIG. 20  is a side cross section view of an embodiment of the dampening device. 
         FIG. 21  is a side cross section view of an embodiment of the dampening device. 
         FIG. 22  is a side cross section view of an embodiment of the dampening device. 
         FIG. 23  is a side cross section view of an embodiment of the dampening device. 
         FIG. 24  is a side cross section view of an embodiment of the dampening device. 
         FIG. 25  is a perspective view of an implementation of the dampening devices. 
         FIG. 26  is a perspective view of an assembly of the dampening devices. 
         FIG. 27  is a perspective view of an assembly of the dampening devices. 
     
    
    
     DETAILED DESCRIPTION OF THE INVENTION 
     The present invention is a dampening device for protecting shipping and storage containers and/or pallets from shocks and vibrations. A first embodiment of the dampening device  10  is illustrated in  FIG. 1 , and includes an annular outer side wall  12  surrounding an annular inner side wall  14 . Both side walls  12 / 14  extend between a top wall  16  and bottom wall  18 . The outer side wall  12  has an outwardly protruding convex cross sectional shape, while the inner side wall  14  has a cylindrical shape (i.e. a rectangular cross sectional shape). The bottom wall  18  rests on, and is preferably bolted to, a support panel  20  (e.g. such as the deck of a pallet or other support structure) by a bolt  22  engaged with the support panel  20  and a threaded hole  24  in bottom wall  18 . The top wall  16  supports, and is preferably bolted to, a floating panel  26  (i.e. the bottom of the shipping and/or storage container, or other structure, which supports the fragile article(s) being protected) by a bolt  28  engaged with the floating panel  26  and a threaded hole  30  in top wall  16 . Threaded holes  24  and  30  preferably include a nut (e.g. a t-nut) mounted in a hole passing through the respective wall. 
     Dampening device  10  is made of a resilient material that allows outer and inner side walls  12 / 14  to flex and absorb energy from shocks and vibrations. Examples of suitable materials include polymeric material such as rubber, low-density or linear low density polyethylene, high density polyethylene, polyester, polypropylene, the family of polyolefin resins, vinyl acetate split or spun into synthetic fibers or modified to take on the elastic properties of a rubber or to produce a number of copolymers, fiberboard, molded fiber, molded urethane, molded ethylene, molded styrene, and/or ecology friendly materials such as corn starch or maze starch. Low density poly ethylene has been determined to work exceedingly well. The dampening device  10  can be made by molding two halves separately and attaching them together. Inner side wall  14  can be integrally formed with top/bottom walls  16 / 18 , or formed separately and assembled together (and held in place by annular ridges  32  extending inwardly from top and bottom walls  16 / 18 ). 
     It has been discovered that two concentric side walls of different cross sectional size and/or shape provide superior shock and vibration dampening (both vertical and horizontal components) between top and bottom walls  16 / 18 , while at the same time supporting the weight of the floating panel  26  with the desired flexure of the outer/inner side walls  12 / 14  in a static state (under the weight of the supported floating panel  26  without shocks and vibrations). As damping device  10  compresses under the weight and shock of a load, the curved outer side wall  12  flexes, with portions of the outer side wall  12  closest to the floating panel  26  and support panel  20  engaging therewith as device  10  compresses to provide increased resilient support and dampening. The increase in resilient support and dampening is gradual with the compression of the device  10  because of the convex shape of the outer side wall  12 . The majority of the weight is supported by the inner side wall  14 , which can flex inwardly or outwardly under heavy loads. The dimensions and materials can be tailored to provide the desired dampening and load requirements (e.g. vibration dampening up to 300 Hz, shock dampening up to 25 g&#39;s, shock dampening up to certain drop heights, total load support up to two tons, etc.). For example, the outer and inner side walls  12 / 14  can have equal or different thicknesses. Additional dampening features can be added as needed. For example,  FIG. 2  illustrates the addition of a spiral-shaped channel  34  along inner side wall  14 , and a spring  36  engaged with the channel and top/bottom walls  16 / 18  for providing additional elastic force and dampening between top and bottom walls  16 / 18  (in addition to the elastic force and dampening provided by inner and outer side walls  14 / 12 ). 
     The shapes of outer and/or inner side walls  12 / 14  can be tailored to meet the desired dampening and load requirements. For example,  FIGS. 3 and 4  are alternate embodiments of  FIGS. 1 and 2 , respectively, where the inner side wall  14  has an outwardly projecting convex cross sectional shape instead of a cylindrical shape, which is easier to flex and compress for lighter loads (i.e. provides less compression strength). With this configuration, under load conditions that compress the dampening device  10 , both the inner and outer side walls  14 / 12  flex outwardly to absorb the weight of the load as well shocks and vibrations to the load. Changing the radius of curvature of inner and/or outer side walls  14 / 12  changes the resiliency of the overall device  10 . A spring  38  can additionally be provided inside of inner side wall  14  (and extending between top and bottom walls  16 / 18 ), as illustrated in  FIG. 5 ,  FIGS. 6 and 7  are alternate embodiments of  FIGS. 1 and 2 , respectively, where the inner side wall  14  has a conical shape (i.e. with a smaller lateral dimension at the top wall  16  than at the bottom wall  18 ) to direct the direction of flex and affect the overall resiliency of the device  10 . 
       FIG. 8  is an alternate embodiment of  FIG. 1 , where the inner side wall  14  has a double conical shape, with two conical portions  14   a , and  14   b  with the wider ends meeting each other and the narrower ends disposed at the top/bottom walls  16 / 18  (le, reverse hour glass). The point at which the two conical portions  14   a / 14   b  meet provides a point of flexure  15  at which the diameter of inner side wall  14  expands as the dampening device  10  is compressed. Point of flexure  15  is an abrupt angle change in the direction of the wall, which will exhibit a reduced resistance to flexing (i.e. flex more readily) compared to curved or straight portions of the wall. Therefore, the angled portions  14   a / 14   b  of inner side wall  14  will flex easier about the point of flexure  15  compared to the straight portions of inner side wall  14 . 
       FIG. 9  is an alternate embodiment of  FIG. 1 , where the inner side wall  14  has a double arcuate cross sectional shape, with inwardly curved concave portions  14   c  and  14   d  extending from the top and bottom wall  16 / 18  respectively, and meeting together to provide a point of flexure  15 . Increased compression resistance can be achieved if the dimensions of the inner/outer side walls  14 / 12  are such that point of flexure  15  of inner side wall  14  contacts the outer side wall  12  during the compression of device  10 . 
       FIG. 10  is an alternate embodiment of  FIG. 1 , where the inner side wall  14  is replaced with spring  38 . 
       FIGS. 11-12  are alternate embodiments of  FIGS. 3 and 6 , where the cross section of the outer side wall  12  includes a straight portion  12   a . A straight wall portion will be harder to flex than a curved wall portion, providing more compression strength. The cross sectional straight portion  12   a  reduces the amount of the outer side wall  12  that is curved (which is what flexes more during compression, shock and vibration), and thus increases the resilience of the outer side wall  12  for heavier loads.  FIG. 13  is an alternate embodiment of  FIG. 5 , where the inner side wall  14  has a double conical shape (see  FIG. 8 ) and the cross section of the outer side wall  12  includes a straight portion  12   a.    
       FIG. 14  is an alternate embodiment of  FIG. 3 , where outer side wall  12  has a double arcuate cross sectional shape, with inwardly curved concave portions  12   c  and  12   d  extending from the top and bottom walls  16 / 18  respectively, and meeting together to provide a point of flexure  15 . The point of flexure  15  in outer side wall  12  reduces the compression strength for the outer side wall  12  without affecting the compression strength for the inner side wall  14 . 
       FIG. 15  is an alternate embodiment of  FIG. 9 , where outer side wall  12  has a triple arcuate cross sectional shape, with outwardly curved convex portions  12   e  and  12   f  and an inwardly curved concave portion  12   g  therebetween. In this configuration, the outer side wall  12  includes two points of flexure  15 , and the inner side wall  14  includes a single point of flexure  15 . The center portions of inner and outer walls  14 / 12  flex in opposite directions as device  10  is compresses. Point of flexure  15  of inner side wall  14  can abut inwardly moving concave portion  12   g  of outer side wall  12 , to provide increased compression strength and resistance should device  10  be compressed beyond a predetermined amount. 
       FIG. 16  is an alternate embodiment of  FIG. 6 , where outer side wall  12  includes flat portion  12 , and the bottom wall  18  is shaped as a ring with an opening  40  exposing the inner surface of inner side wall  14 .  FIG. 17  is an alternate embodiment of  FIG. 16 , where the top wall  16  is flat and extends further away from the threaded hole  30 , and the curved portion of outer side wall  12  is smaller. This configuration gives the dampening device  10  a greater compression strength for larger loads.  FIG. 18  illustrates the mounting of the embodiment of  FIG. 16  between the floating panel  26  and support panel  20 , with both a bolt  42  and spring  44  extending through opening  40 .  FIG. 19  illustrates an alternate mounting shown in  FIG. 18 , where the bolt  42  extends through opening  40 , but spring  44  extends along that portion of the bolt  42  outside of opening  40 . Screws  46  can be used to secure the ring shaped bottom wall  18  to the support panel  20 , as illustrated in  FIG. 20 . 
     Fasteners  48  can be used to removably engage with one or more tabs  50  formed on bottom wall  18  to removably secure bottom wall  18  to support panel  20 , as illustrated in  FIGS. 21-22 . Fasteners can be stand alone, or formed within a continuous ring, and attached to support panel  20  via screws  46 . Fasteners  48  can be configured with holes or slots such that the bottom wall  18  is secured to fasteners  48  by rotating device  10  to engage tabs  50  into holes/slots of fasteners  48 , and bottom wall  18  is released from fasteners by rotating device  10  in the opposite direction to free tabs  50  from fasteners  48 . 
     The flexing characteristics of inner and outer side walls  14 / 12  in any of the embodiments described herein can be optimized by selectively including dimples that form small points of flexure that increase the flexibility of select portions of each wall. For example,  FIG. 23  is an alternate embodiment to  FIG. 16 , wherein dimples  52  are formed in both the inner and outer side walls  14 / 12 . Those portions of the side walls containing dimples  52  are more flexible than other portions of the walls. The sizes, numbers and shapes of dimples can be varied to provide varying degrees of flexing characteristics, as illustrated in  FIG. 24 , to meet the dampening requirements of the fragile article being protected. Dimples  52  can be spot dimples (e.g. small discrete deformations in the wall in which it is formed) or elongated dimples (e.g. annular deformations that extend all the way around the wall in which it is formed). 
       FIG. 25  illustrates the implementation of dampening device  10 . Specifically, multiple dampening devices  10  can be disposed between support panel  20  and floating panel  26 . Alternately and/or additionally, dampening devices  10  can be disposed underneath support panel  20  (or underneath any panel that supports the weight of the fragile articles).  FIG. 25  illustrates the use of dampening devices  10  in a nested fashion, where they are disposed both between panels  20  and  26 , as well as underneath panel  20  for placement on the floor, to absorb shocks both externally and internally to the support panel  20 . 
       FIG. 26  illustrates a bracket  54  that includes a horizontal member  54   a  and two orthogonal vertical members  54   b  and  54   c  (i.e. each member  54   a / 54   b / 54   c  extending in a different plane with all three planes orthogonal to each other). A dampening device  10  is mounted to each member  54   a / 54   b / 54   c . The bracket  54  supports the corner of a floating panel, and cushions that corner from shocks and vibrations in the vertical direction and both orthogonal horizontal directions. Multiple brackets  54  can be integrally formed together, and extend along all four side corners of a container  56 , as illustrated in  FIG. 27 , to position three devices  10  on each of three sides of a corner, for two adjacent corners. 
     The various shapes, points of flexure, and combinations thereof and of the various subcomponents of the device  10 , dictate the effective spring constant and dampening effect for each element and the dampening device  10  as a whole. 
     It is to be understood that the present invention is not limited to the embodiment(s) described above and illustrated herein, but encompasses any and all variations falling within the scope of the appended claims. For example, references to the present invention herein are not intended to limit the scope of any claim or claim term, but instead merely make reference to one or more features that may be covered by one or more of the claims. Materials, processes and numerical examples described above are exemplary only, and should not be deemed to limit the claims. All of the embodiments can be reversed in orientation (i.e. whereby the top wall  16  contacts and/or is mounted to the support panel  20 , and the bottom wall  18  contacts and/or is mounted to the floating panel  26 ). Support panel  20  can be omitted, where the dampening device would rest on the floor.