Abstract:
A snubbed isolator is provided having an increased capability for three-dimensional damping of vibrations for a component affixed or attached to a structure through the snubbed isolator, where the snubbed isolator is attached to the structure. The snubbed isolator includes a mounting plate for attaching to the structure, an elastomeric element, and a stem for mounting the component. The elastomeric element is disposed between the mounting plate and the stem.

Description:
CROSS-REFERENCE TO RELATED APPLICATIONS 
       [0001]    The present application claims priority to U.S. Provisional Patent Application No. 61/786,877 filed on Mar. 15, 2013 by Rawson et al., entitled “VIBRATION ISOLATION MEMBER”, and the present application claims priority to co-pending U.S. Provisional Patent Application No. 61/694,002 filed on Aug. 28, 2012 by Rawson et al., entitled “VIBRATION ISOLATION MEMBER”, and the present application claims priority to co-pending U.S. Provisional Patent Application No. 61/694,018 filed on Aug. 28, 2012 by Rawson et al., entitled “VIBRATION ISOLATION MEMBER”, all of which are incorporated by reference herein as if reproduced in their entirety. 
     
    
     FIELD OF INVENTION 
       [0002]    This invention relates to the field of vibration control using vibration isolation devices having a combination of elastomeric elements and mounting fixtures. 
       BACKGROUND 
       [0003]    Isolating vibrations often require the use of snubbed isolators and/or a plurality of isolator devices. The problem is that no isolator provides for a means to specifically avoid hard metal-to-metal impact and associated clicking noise during transient events. When a working elastomer is employed, current isolators typically impact the performance of the elastomer. If space is limited, the isolators usually use less elastomeric product, which further increases the impact on the isolator performance. 
         [0004]    Additionally, none of the current isolators provide for a high-load capability and a high-isolation performance while maintaining substantially smaller sizes. There is a need for a snubbed isolator that is capable of three-dimensional damping of vibrations for a structure that it is attached to. 
       SUMMARY 
       [0005]    The invention provides for a snubbed isolator and an isolator assembly to reduce vibrations in a structure. 
         [0006]    In one aspect, a snubbed isolator is provided. The snubbed isolator comprises an inner member, an outer member, an interlock, an elastomeric element and at least one snubbing elastomeric element. The inner member having a lower member including an upper surface and a base, wherein the base is wider than the upper surface. The inner member having a stem integral with the lower member, the stem including a top, wherein the top is oppositely positioned from the base. The inner member having a surface associated with the top of the stem, the surface being capable of bearing load. The outer member positioned outwardly from the inner member, the outer member having a surface that is wider near the base of the lower member and narrower proximate the upper surface of the lower member. The interlock being between the inner and outer members. The elastomeric element bonded between the inner and outer members. The snubbing elastomeric element bonded to the inner member and positioned to snub against a mounting structure. 
         [0007]    In another aspect, an isolator assembly is provided. The isolator assembly comprises a mounting plate and a snubbed isolator device. The mounting plate has a plate contoured surface. The snubbed isolator device is proximate to and capable of being attached to the mounting plate. The snubbed isolator device includes: an inner member, a first elastomeric element, a second elastomeric element and an outer member. The inner member has a first and second side. The first elastomeric element is bonded to the first side and the second elastomeric element is bonded to the second side. The second elastomeric element has a contoured surface proximate the plate contoured surface. The outer member is bonded to the first elastomeric element opposite from the first side, and wherein the outer member is positioned proximate to and capable of being attached to the mounting plate. 
         [0008]    In another aspect, an isolator assembly is provided. The isolator assembly comprises a mounting plate and a snubbed isolator device. The mounting plate has a plate contoured surface. The snubbed isolator device is proximate to and capable of being attached to the mounting plate. The snubbed isolator device includes: an inner member, a first elastomeric element, a second elastomeric element and an outer member. The inner member has a first and second side. The first elastomeric element is proximate to the first side and the second elastomeric element is proximate to the second side. The second elastomeric element has a contoured surface bonded to the plate contoured surface. The outer member is bonded to the first elastomeric element opposite from the first side, and wherein the outer member is proximate to and capable of being attached to the mounting plate. 
         [0009]    In another aspect, an isolator assembly is provided. The isolator assembly comprises a mounting plate and a snubbed isolator device. The mounting plate has a plate contoured surface. The snubbed isolator device is proximate to and capable of being attached to the mounting plate. The snubbed isolator device includes: an inner member, a first elastomeric element, a second elastomeric element and an outer member. The inner member has a first and second side. The first elastomeric element is proximate to the first side and the second elastomeric element is bonded to the second side. The second elastomeric element has a contoured surface proximate the plate contoured surface. The outer member is bonded to the first elastomeric element opposite from the first side, and wherein the outer member is proximate to and capable of being attached to the mounting plate. 
         [0010]    In another aspect, an isolator assembly is provided. The isolator assembly comprises a mounting plate and a snubbed isolator device. The mounting plate has a plate contoured surface. The snubbed isolator device is proximate to and capable of being attached to the mounting plate. The snubbed isolator device includes: an inner member, a first elastomeric element, a second elastomeric element and an outer member. The inner member has a first and second side. The first elastomeric element is bonded to the first side and the second elastomeric element is proximate to the second side. The second elastomeric element has a contoured surface bonded to the plate contoured surface. The outer member is proximate the first elastomeric element opposite from the first side, and wherein the outer member is proximate to and capable of being attached to the mounting plate. 
         [0011]    In another aspect, an isolator assembly is provided. The isolator assembly comprises a common mounting plate and at least two snubbed isolator devices. The common mounting plate has at least two plate contoured surfaces. The snubbed isolator devices are proximate to and capable of being attached to the common mounting plate, wherein each snubbed isolator device includes: an inner member, a first elastomeric element, a second elastomeric element and an outer member. The inner member has a first and second side. The first elastomeric element is bonded to the first side and the second elastomeric element is bonded to the second side. The second elastomeric element has a contoured surface proximate the plate contoured surface. The outer member is bonded to the first elastomeric element opposite from the first side, and wherein the outer member is proximate to and capable of being attached to the common mounting plate. 
         [0012]    Numerous objects and advantages of the invention will become apparent as the following detailed description of the preferred embodiments is read in conjunction with the drawings, which illustrate such embodiments. 
     
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         [0013]      FIG. 1  illustrates a plan view of a snubbed isolator. 
           [0014]      FIG. 2  illustrates a section view of a snubbed isolator taken along section  2 - 2  of  FIG. 1 . 
           [0015]      FIG. 3A  illustrates a plan view of an isolator assembly having a snubbed isolator device on a mounting plate. 
           [0016]      FIG. 3B  illustrates a perspective view of an isolator assembly having a snubbed isolator device on a mounting plate. 
           [0017]      FIG. 4  illustrates a perspective view of an isolator assembly having a snubbed isolator device with a threaded stem hole secured to a mounting plate. 
           [0018]      FIG. 5  illustrates a plan view of an isolator assembly having at least two snubbed isolator devices on a common mounting plate. 
           [0019]      FIG. 6  illustrates a section view of an isolator assembly taken along section  6 - 6  of  FIG. 5 . 
           [0020]      FIG. 7  illustrates a perspective view of an isolator assembly having at least two snubbed isolator devices on a common mounting plate. 
       
    
    
     DETAILED DESCRIPTION 
       [0021]    Reference is made in detail to the present embodiments of the invention, examples of which are illustrated in the accompanying drawings. 
         [0022]    Generally, the invention provides an isolator having a mating interface between an inner and outer member with an elastomeric element between and having an additional elastomeric element providing snubbing capability to the isolator. The snubbed isolator is able to provide elastomer pre-compression within the bonded isolator, thereby improving the overall fatigue life of the snubbed isolator. The contoured geometry of the snubbed isolator and the interface between the inner member, outer member and elastomeric elements also provides multi-direction stiffness control. An assembly of side-by-side snubbed isolator devices can support an applied moment. This one-piece assembly is easier to install, compared to using individual snubbed isolator devices. 
         [0023]    Referring to  FIGS. 1 and 2 , a snubbed isolator  10  is provided as one embodiment. Snubbed isolator  10  is comprised of inner member  12 , outer member  14 , and elastomeric element  16 . Elastomeric element  16  is bonded between inner member  12  and outer member  14 . Outer member  14  includes conical surface  18 , exit hole  20  and mounting plate  22 , which is also referred to as base flange  22 . Inner member  12  includes stem  24  and lower member  25 . Stem  24  is integral with lower member  25 . Stem  24  includes flange  28  and channel  30 . Lower member  25  includes conical surface  26 , upper surface  27  and base  32 . Base  32  is wider than upper surface  27 . Stem  24  is sized according to design need. Flange  28  is positioned on stem  24  and provides for the load-bearing surface of stem  24 . Channel  30  is also positioned on stem  24 . Base  32  and base elastomer  34  are positioned at the lower end of lower member  25  of inner member  12 , with base elastomer  34  affixed to lower member  25  at base  32 . Base elastomer  34  is also referred to as snubbing elastomeric element  34 . 
         [0024]    Snubbed isolator  10  is interlocked by the outer diameter of base  32  of inner member  12  being greater than the diameter of exit hole  20  of outer member  14 . This interlocking interference between base  32  and exit hole  20  is interlock  200 . Interlock  200  prevents inner member  12  from being pulled out of outer member  14 . 
         [0025]    As illustrated in  FIGS. 1 and 2 , the elastomeric snubbing using base elastomer  34  avoids hard (metal-to-metal) contact with any isolator brackets or support structures during high-displacement events (transients, etc.) in the axial direction. In this embodiment base elastomer  34  is referred to as snubbing elastomeric element  34 . The elastomeric snubbing feature of base elastomer  34  is not part of the working area of elastomeric element  14 , or the “working elastomer”. Snubbed isolator  10  is designed with conical surfaces  18  and  26  on the outer member  14  and inner member  12 , respectively, for axial-to-radial stiffness control. However, it is understood that other geometries are possible. 
         [0026]    Channel  30  of stem  24  is sized with a diameter D 4 . D 4  is determined by the use of snubbed isolator  10  and is positioned between flange  28  and upper surface  27 . Flange  28  carries load on load-bearing surface  31 , and it is used for mating components. Diameter D 5  in  FIG. 2  illustrates a non-limiting example of a diameter associated with load-bearing surface  31 . Load-bearing surface  31  is coincident with top  33 . 
         [0027]    Stem  24  can be modified to incorporate other features or interfaces (keyways, grooves, flanges, helical wire inserts, etc.). In the embodiment illustrated in  FIGS. 1 and 2 , stem  24  has stem hole  36 . Stem hole  36  provides for additional mounting capabilities, such as a non-limiting example of a threaded interior  117  illustrated in  FIG. 6  for mounting a screw (not shown) and securing it therethrough. Other mounting device configurations are considered such as bolts and rivets. 
         [0028]    Inner member  12  and outer member  14 , in the embodiment illustrated in  FIGS. 1 and 2 , are preferably fabricated out of stainless steel and aluminum, respectively, although other combinations, including thermoplastics and composites, will work depending upon the particular application. 
         [0029]    Referring to snubbed isolator  10  illustrated in  FIG. 1 , outer length L 1  defines a first dimension of mounting plate  22  and outer width W 1  defines a second dimension of mounting plate  22 . Mounting holes  38  are disposed through mounting plate  22  and have a hole diameter of D 1 . Hole diameter D 1  is defined by the mounting requirements of the mounting device (not shown) and devices used to mount snubbed isolator  10  to a structure. Preferably, snubbed isolator  10  has at least two mounting holes  38  disposed through mounting plate  22 . As illustrated, mounting holes  38  have a center  40  and the distance between center  40  of mounting holes  38  is hole center length L 2 . D 2  illustrates the diameter of the beginning of the outer conical surface  42  of outer member  14 . Stem  24  also has a hole disposed therethrough and D 3  illustrates the inner diameter of stem hole  36 . 
         [0030]    Table 1 indicates that D 3  is sufficiently sized to accept a #10-32 threaded bolt or other mounting device. It is known to those having skill in the art that any mounting device can be made to be compatible with D 3 . 
         [0031]    Referring to snubbed isolator  10  illustrated in  FIG. 2 , total flange depth DP 1  defines the overall height or depth of snubbed isolator  10 . The diameter of channel  30  is illustrated by D 4  and the diameter of mounting flange  28  is illustrated by D 5 . The height of channel  30  is illustrated by H 1 . If used, mounting flange thickness T 1  is defined by the particular load-bearing requirement. 
         [0032]    As illustrated, snubbed isolator  10  has cavity  44  positioned below inner member  12 . Cavity  44  has a cavity depth of DP 2 . Base elastomer  34 , or snubbing elastomeric element  34 , of inner member  12  extends into a portion of cavity  44 . 
         [0033]    Mounting plate  22  of snubbed isolator  10  is illustrated as having curved ends with the radius of end curve being R 1 . 
         [0034]    Table 1 below refers to the embodiment illustrated in  FIGS. 1 and 2 , wherein a non-limiting representative of snubbed isolator  10  has the following values: 
         [0000]    
       
         
               
               
             
           
               
                 TABLE 1 
               
               
                   
               
               
                   
                 Representative Value 
               
               
                 Reference 
                 (measurement = about) 
               
               
                   
               
             
             
               
                 L1 = Outer length 
                 2.220 inches 
               
               
                 L2 = Hole center length 
                 1.700 inches 
               
               
                 W1 = Outer width 
                 1.330 inches 
               
               
                 D1 = Hole diameter 
                 0.131 inches 
               
               
                 D2 = Base diameter 
                 1.200 inches 
               
               
                 D3 = Stem hole diameter 
                 sufficient to accept a #10-32 
               
               
                   
                 threaded bolt or mounting device 
               
               
                 D4 = Channel diameter 
                 0.340 inches 
               
               
                 D5 = Flange diameter 
                 0.435 inches 
               
               
                 R1 = Radius of end curve 
                 0.260 inches 
               
               
                 DP1 = Flange total depth 
                 0.685 inches 
               
               
                 DP2 = Cavity depth 
                 0.075 inches 
               
               
                 H1 = Channel height 
                 0.220 inches 
               
               
                 T1 = Mounting flange thickness 
                 0.020-0.050 inches         
               
               
                   
               
             
          
         
       
     
         [0035]    In use, the snubbing feature of snubbed isolator  10  eliminates “clicking” noises due to metal-to-metal contact. It also reduces wear on the contacting metal components. Snubbing, in general, limits deflection for protection of the isolator “working elastomer”. The snubbing feature is particularly useful when a soft isolator is desired, with limited envelope available for clearance. A large load-bearing area on the inner member stem distributes clamping and application forces, while reducing stress on mating components. This is particularly useful with the use of advance composite materials. 
         [0036]    Referring to  FIGS. 3A-4 , an isolator assembly  100  embodiment is provided using a snubbed isolator device  102  proximate to and capable of being attached to mounting plate  103 , also known as single base flange  103 . Mounting plate  103  has plate contoured surface  106 .  FIGS. 3A-4 , illustrate a single isolator assembly with a single snubbed isolator device  102  on a single mounting plate  103 . Unless otherwise indicated, snubbed isolator device  102  use the same reference character numbers as identified above for snubbed isolator  10 . 
         [0037]    Snubbed isolator device  102  is comprised of inner member  108 , outer member  110 , inner elastomeric element  112  and outer elastomeric element  114 . Elastomeric elements  112  and  114  are pre-compressed. In one embodiment, elastomeric element  114  is bonded between inner member  108  and outer member  110 . 
         [0038]    Inner member  108  includes stem  116  and conical member  118 . Stem  116  is sized according to design need. Stem  116  is sized to provide a load-bearing capacity based upon a particular design need of the end use. As illustrated, stem  116  has stem hole  117 . Stem hole  117  provides for mounting capabilities, such as a non-limiting example of a screw (not shown) being secured therethrough. Other mounting device configurations are considered such as bolts and rivets. Conical member  118  of inner member  108  includes first side  120  and second side  122 . Elastomer elements  114  and  112  are bonded on both first side  120  and second side  122 , respectively, of inner member  108 . 
         [0039]    Outer member  110  includes conical member  124 . In the embodiment above, conical member  124  of outer member  110  is bonded to elastomeric element  114 , which is also bonded to first side  120  of conical member  118 . Outer member  110  is in contact with mounting plate  103 . Elastomeric element  112  is bonded to second side  122  of conical member  118  and is in contact with plate contoured surface  106  of mounting plate  103 . 
         [0040]    Snubbed isolator devices  102  of isolator assembly  100  are interlocked by the outer diameter of base  126  of inner member  108  being greater than the diameter of exit hole  128  of outer member  110 . Interlock  200 , as represented in  FIG. 6  for a dual system, prevents inner member  108  from being pulled out of outer member  110 . 
         [0041]    One elastomer section  114  is positioned to mechanically react against outer member  110  and other elastomer section  112  is positioned to mechanically react against mounting plate  103  at contoured surface  106 . In this embodiment, elastomer  112  is not bonded to mounting plate  103 . 
         [0042]    Mounting plate  103  and adjacent elastomer member  112  have a contoured interface for multi-direction load capability. The contoured interface is where contoured surface  106  and elastomer member  112  are proximate to each other. Contoured surface  106  of mounting plate  103  is capable of reacting load in multiple directions. 
         [0043]    Mounting plate  103  material is ideally thermoplastic or a composite to reduce both the per-unit cost and weight. However, mounting plate  103  material may also be metal. 
         [0044]    When installed, the snubbed isolator device  102  pull out load (axial tension) is supported by inner member  108  and outer member  110 . As illustrated, mounting plate  103  is not in a load path. 
         [0045]    The embodiment illustrated in  FIGS. 3A-4  is assembled using integral snap-in features, although other methods (rivets, adhesive, etc.) will also work. The snubbed isolator device  102  and common mounting plate  102 , may also be left unassembled until installation. 
         [0046]    Other embodiments of isolator assembly  100  include snubbed isolator device  102  which is comprised of inner member  108 , outer member  110 , inner elastomeric element  112  and outer elastomeric element  114 . Elastomeric elements  112  and  114  are pre-compressed. In one embodiment, elastomeric element  114  is bonded between inner member  108  and outer member  110  and elastomeric element  112  is only bonded to inner member  108 . In another embodiment, elastomeric element  114  is bonded to outer member  110  and elastomeric element  112  is bonded to inner member  108 . In another embodiment, elastomeric element  114  is bonded to outer member  110  and elastomeric element  112  is bonded to contoured surface  106  of mounting plate  103 . In another embodiment, elastomeric element  114  is bonded to inner member  108  and elastomeric element  112  is bonded to contoured surface  106  of mounting plate  103 . Other combinations available but not addressed for the sake of brevity. 
         [0047]    Referring to  FIGS. 5-7 , another alternative isolator assembly  100  embodiment is provided using at least two snubbed isolator devices  102  proximate to and capable of being attached to a single, common mounting plate  104 , also known as base flange  104 . Common mounting plate  104  has at least two plate contoured surfaces  106 . The number of snubbed isolator devices  102  is not limited to two on a single common mounting plate  104 . Unless otherwise indicated, snubbed isolator devices  102  use the same reference character numbers as identified above for snubbed isolator  10 . 
         [0048]    Each snubbed isolator device  102  is comprised of inner member  108 , outer member  110 , inner elastomeric element  112  and outer elastomeric element  114 . Elastomeric elements  112  and  114  are pre-compressed. Elastomeric element  114  is bonded between inner member  108  and outer member  110 . 
         [0049]    Inner member  108  includes stem  116  and conical member  118 . Stem  116  is sized according to design need. Stem  116  is sized to provide a load-bearing capacity based upon a particular design need of the end use. As illustrated, stem  116  has stem hole  117 . Stem hole  117  provides for mounting capabilities, such as a non-limiting example of a screw (not shown) being secured therethrough. Other mounting device configurations are considered such as bolts and rivets. Conical member  118  of inner member  108  includes first side  120  and second side  122 . Elastomer elements  114  and  112  are bonded on both first side  120  and second side  122 , respectively, of inner member  108 . 
         [0050]    Outer member  110  includes conical member  124 . Conical member  124  of outer member  110  is bonded to elastomeric element  114 , which is also bonded to first side  120  of conical member  118 . Outer member  110  is in contact with common mounting plate  104 . Elastomeric element  112  is bonded to second side  122  of conical member  118  and is in contact with contoured surface  106  of common mounting plate  104 . 
         [0051]    Snubbed isolator devices  102  of isolator assembly  100  are interlocked by the outer diameter of base  126  of inner member  108  being greater than the diameter of exit hole  128  of outer member  110 . Interlock  200  prevents inner member  108  from being pulled out of outer member  110 . 
         [0052]    One elastomer section  114  is positioned to mechanically react against outer member  110  and other elastomer section  112  is positioned to mechanically react against common mounting plate  104  at contoured surface  106 . In this embodiment, elastomer  112  is not bonded to common mounting plate  104 . 
         [0053]    Common mounting plate  104  and adjacent elastomer member  112  have a contoured interface for multi-direction load capability. The contoured interface is where contoured surface  106  and elastomer member  112  are proximate to each other. Contoured surface  106  of common mounting plate  104  are capable of reacting load in multiple directions. 
         [0054]    Common mounting plate  104  material is ideally thermoplastic or a composite to reduce both the per-unit cost and weight. However, common mounting plate  104  material may also be metal. 
         [0055]    When installed, the snubbed isolator device  102  pull out load (axial tension) is supported by inner member  108  and outer member  110 . As illustrated, common mounting plate  104  is not in a load path. With respect to the pull out load for the embodiment where elastomeric element  112  is not bonded to contoured surface  106 , inner member  108 , elastomeric element  114 , and outer member  110  define the load path of snubbed isolator device  102 , where inner member  108  provides a load to elastomeric element  114  which in turn provides a load to outer member  110 . 
         [0056]    The embodiment illustrated in  FIGS. 5-7  is assembled using integral snap-in features, although other methods (rivets, adhesive, etc.) will also work. The three components, the two snubbed isolator devices and common mounting plate  104 , may also be left unassembled until installation. 
         [0057]    Referring to snubbed isolator assembly  100  illustrated in  FIG. 5 , outer length L 3  defines a first dimension of common mounting plate  104  and outer width W 2  defines a second dimension of common mounting plate  104 . Mounting holes  130  are disposed through common mounting plate  104  and have a hole diameters of D 6  and hole diameter of D 7 . Hole diameters D 6  and D 7  are the same. Mounting hole  130  is illustrated in  FIG. 5  with each hole diameter thereon. Similar to the embodiment in  FIGS. 1 and 2 , hole diameters D 6  and D 7  are defined by the mounting requirements of the mounting device (not shown) and devices used to mount isolator assembly  100  to a structure. Preferably, isolator assembly  100  has at least four mounting holes  130  disposed through common mounting plate  104  and outer members  110 . As illustrated, mounting holes  130  have a center  132  and the distance between center  132  of mounting holes  130  in a first direction is outer hole center length L 4 , and in a second direction is outer hole center width W 3 . As illustrated outer hole center length L 4  is measured between separate snubbed isolator devices  102 , and outer hole center width W 3  is measured across a single snubbed isolator device  102 . 
         [0058]    D 8  illustrates the diameter of the beginning of the outer conical surface  134  of outer member  110 . Stem hole  117  is a hole disposed through stem  116 . D 9  illustrates the inner diameter of stem hole  117 . Stem hole center  136  is the center of the hole in stem  116  when viewed from the plan view. The distance between stem hole center  136  and an outer hole center of mounting hole  130  is W 4 . 
         [0059]    Referring to isolator assembly  100  illustrated in  FIG. 6 , flange depth DP 3  defines the overall height or depth of isolator assembly  100 . Stem  116  is illustrated having a diameter of D 10 . 
         [0060]    As illustrated, isolator assembly  100  has cavity  138  positioned below stem  116 . Stem  116 , stem hole  117  and cavity  138 , in combination, provides for a point to secure devices to isolator assembly  100 . Note, any securing device used with isolator assembly  100  does not have to extend into cavity  138 . 
         [0061]    Common mounting plate  104  of isolator assembly  100  is illustrated as having curved ends for each snubbed isolator device  102 . These curved ends align with the radius R 2  of the curve of mounting plate  22  of snubbed isolator device  102 . 
         [0062]    Table 2 below refers to the embodiment illustrated in  FIGS. 3A-7 , wherein a non-limiting representative of isolator assembly  100  has the following values: 
         [0000]    
       
         
               
               
               
             
           
               
                   
                 TABLE 2 
               
               
                   
                   
               
               
                   
                   
                 Representative Value 
               
               
                   
                 Reference 
                 (measurement = about) 
               
               
                   
                   
               
             
             
               
                   
                 L3 = Outer length 
                 2.640 inches 
               
               
                   
                 L4 = Hole center length 
                 1.380 inches 
               
               
                   
                 W2 = Outer width 
                 2.210 inches 
               
               
                   
                 W3 = Hole center length 
                 1.620 inches 
               
               
                   
                 W4 = Hole center length 
                 0.810 inches 
               
               
                   
                 D6 = Mounting hole diameter 
                 0.103 inches 
               
               
                   
                 D7 = Mounting hole diameter 
                 0.103 inches 
               
               
                   
                 D8 = Base diameter 
                 1.122 
               
               
                   
                 D10 = Stem diameter 
                 0.445 inches 
               
               
                   
                 DP3 = Overall mounting height 
                 0.375 inches 
               
               
                   
                 R2 = Radius of end curve 
                 0.180 inches 
               
               
                   
                   
               
             
          
         
       
     
         [0063]    The use of common mounting plate  104  provides for isolator assembly  100  as a one-piece device to improve the ease of installation. Opposing elastomer sections  112  and  114  on each side of the conical member  118  of inner member  108  provide for snubbing in all directions, while maintaining vibration isolation. In this configuration, one side is always in a compressive state. Pre-compressing the elastomer significantly reduces fatigue of the elastomer associated with long-term use and greatly increases the life of the isolator assembly. The interface between un-bonded elastomeric element  112  and contoured surface  106  of common mounting plate  104  provides for an increase of the axial compression and radial load capability of isolator assembly  100 . The contoured interface provides both axial and radial load capability with axial-to-radial stiffness control 
         [0064]    Other embodiments of the current invention will be apparent to those skilled in the art from a consideration of this specification or practice of the invention disclosed herein. Thus, the present invention is well adapted to carry out the objects and attain the ends and advantages mentioned as well as those inherent therein. While preferred embodiments of the present invention have been illustrated for the purpose of the present disclosure, changes in the arrangement and construction of parts and the performance of steps can be made by those skilled in the art, which changes are encompassed within the scope and spirit of the present invention as defined by the appended claims.