Suspension system for aircraft auxiliary power unit with elastomeric member

Abstract

The present invention broadly comprises an aircraft motion control auxiliary power unit suspension system device, the aircraft motion control auxiliary power unit suspension system device comprising a first motion control nonelastomeric member and a second motion control nonelastomeric member, a first motion control elastomer member disposed to operatively interconnect the first motion control nonelastomeric member and the second motion control nonelastomeric member. The first motion control elastomer member includes an exterior surface coating formed from an elastomeric polymer dissolved in an organic solvent and the elastomeric polymer dissolved in the solvent is applied to an exterior surface of the first motion control elastomer member, the solvent evaporates, and the elastomeric polymer crosslinks.

1 . A method of making an aircraft motion control device, said method comprising steps of:
 providing a first motion control nonelastomeric member,   providing a second motion control nonelastomeric member,   providing a first motion control elastomer, said first motion control elastomer having an exterior surface,   providing an elastomeric coating composition, said elastomeric coating composition comprising an elastomeric polymer dissolved in a solvent,   applying said elastomeric coating composition to said exterior surface of said first motion control elastomer, wherein said solvent evaporates and said elastomeric polymer crosslinks,   disposing said first motion control elastomer to operatively interconnect said first motion control nonelastomeric member and said second motion control nonelastomeric member.   
     
     
         2 . The method of  claim 1 , wherein said elastomeric polymer has a glass transition temperature (Tg) that is less than zero degrees Celsius. 
     
     
         3 . The method of  claim 1 , wherein said elastomeric coating composition includes a silane compound. 
     
     
         4 . The method of  claim 1 , wherein said first motion control elastomer is comprised of an EPDM elastomer. 
     
     
         5 . The method of  claim 1 , wherein said aircraft motion control device is an aircraft auxiliary power unit suspension system motion control device. 
     
     
         6 . The method of  claim 1 , wherein said aircraft auxiliary power unit suspension system motion control device is a suspension mount linkage system, wherein each suspension linkage includes a first elastomeric rod end within which said first motion control elastomer is disposed between said first and second motion control nonelastomeric members. 
     
     
         7 . The method of  claim 1 , wherein said aircraft motion control device is a linkage system with a first suspension linkage including a first and a second terminal end, each having a threaded portion having a same hand;
 a first elastomeric rod end having a threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said threaded portion of said first elastomeric rod end having a hand corresponding to said hand of said threaded portion of said first terminal end of said first suspension linkage; and   
       a second elastomeric rod end having a threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said threaded portion of said second elastomeric rod end having a hand corresponding to said hand of said threaded portion of said second terminal end of said first suspension linkage, wherein said threaded portion of said first elastomeric rod end and said portion of said second elastomeric rod end are of said same hand. 
     
     
         8 . The method of  claim 1 , including incorporating a fungicide into said elastomeric coating composition. 
     
     
         9 . An aircraft motion control auxiliary power unit suspension system device, said aircraft motion control auxiliary power unit suspension system device comprising:
 a first motion control nonelastomeric member and a second motion control nonelastomeric member,   a first motion control elastomer member disposed to operatively interconnect said first motion control nonelastomeric member and said second motion control nonelastomeric member,   said first motion control elastomer member having an exterior surface coating formed from an elastomeric polymer in a solvent, wherein said elastomeric polymer in said solvent is applied to an exterior surface of said first motion control elastomer member, said solvent evaporates, and said elastomeric polymer crosslinks.   
     
     
         10 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , wherein said elastomeric polymer has a glass transition temperature (Tg) that is less than zero degrees Celsius. 
     
     
         11 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , wherein said first motion control elastomer is comprised of an EPDM elastomer. 
     
     
         12 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , further comprising a suspension mount linkage system comprising a plurality of suspension linkages, each having a first and a second elastomeric rod end. 
     
     
         13 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , wherein said elastomeric polymer forming said exterior surface coating on said first motion control elastomer member organically cross-links within said coating itself and inorganically cross-links to said first motion control elastomer member. 
     
     
         14 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , wherein said exterior surface coating is a first of a plurality of coatings and a second of said coatings is applied to said first motion control elastomer member. 
     
     
         15 . The aircraft motion control auxiliary power unit suspension system device of  claim 14 , wherein said second coating organically cross-links within said second coating and inorganically cross-links to said first coating on said exterior surface of said first motion control elastomer member. 
     
     
         16 . The aircraft motion control auxiliary power unit suspension system device of  claim 9 , wherein said device includes a linkage with a first and a second terminal end, each having a threaded portion having a same hand;
 a first elastomeric rod end having a threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said threaded portion of said first elastomeric rod end having a hand corresponding to said hand of said threaded portion of said first terminal end of said linkage; and   
       a second elastomeric rod end having a threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said threaded portion of said second elastomeric rod end having a hand corresponding to said hand of said threaded portion of said second terminal end of said linkage, wherein said threaded portion of said first elastomeric rod end and said portion of said second elastomeric rod end are of said same hand. 
     
     
         17 . An aircraft motion control auxiliary power unit suspension system comprising:
 a first suspension linkage including a first and a second terminal end, each having a helical threaded portion having a same hand;
 a first elastomeric rod end having a helical threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said helical threaded portion of said first elastomeric rod end having a hand corresponding to said hand of said helical threaded portion of said first terminal end of said first suspension linkage; and 
 a second elastomeric rod end having a helical threaded portion and a first motion control elastomer operatively interconnecting a first motion control nonelastomeric member and a second motion control nonelastomeric member, said helical threaded portion of said second elastomeric rod end having a hand corresponding to said hand of said helical threaded portion of said second terminal end of said first suspension linkage, wherein said helical threaded portion of said first elastomeric rod end and said helical portion of said second elastomeric rod end are of said same hand. 
   
     
     
         18 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said first elastomeric rod end includes a non-threaded portion disposed to prevent said suspension link from moving in a first direction when said helical threaded portion of said first terminal end contacts said non-threaded portion of said first elastomeric rod end. 
     
     
         19 . The aircraft motion control auxiliary power unit suspension system of  claim 18 , wherein said second elastomeric rod end includes a non-threaded portion disposed to prevent said suspension link from moving in a second direction when said helical threaded portion of said second terminal end contacts said non-threaded portion of said second elastomeric rod end. 
     
     
         20 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said helical threaded portions of said first and second elastomeric rod ends are right-handed. 
     
     
         21 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said helical threaded portions of said first and second elastomeric rod ends are left-handed. 
     
     
         22 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said helical threaded portions of said first and second elastomeric rod ends have a same pitch. 
     
     
         23 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein epoxy is applied to said helical threaded portions of said first and second elastomeric rod ends during assembly. 
     
     
         24 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein the helical threaded portions of said first and second elastomeric rod ends each have at least two transitional imperfect threads. 
     
     
         25 . The aircraft motion control auxiliary power unit suspension system of  claim 24 , wherein the at least two transitional imperfect threads have a gradually formed shallow depth. 
     
     
         26 . The aircraft motion control auxiliary power unit suspension system of  claim 24 , wherein the at least two transitional imperfect threads have a gradually altered pitch. 
     
     
         27 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said first motion control elastomer member further includes an exterior coating surface formed from an elastomeric polymer dissolved in an organic solvent, wherein said elastomeric polymer dissolved in said solvent is applied to said first motion control elastomer member and said solvent evaporates and said elastomeric polymer crosslinks. 
     
     
         28 . The aircraft motion control auxiliary power unit suspension system of  claim 27 , wherein said elastomeric polymer has glass transition temperature (Tg) that is less than zero degrees Celsius. 
     
     
         29 . The aircraft motion control auxiliary power unit suspension system of  claim 27 , wherein said elastomeric polymer comprises a functionalized hydrogenated high molecular weight copolymer comprising 50-85% at least one repeating unit derived from a conjugated diene monomer; and an active hydrogen-bearing, or ethylenic unsaturated or hydrolysable group-bearing monomer, or graft-linked compound, or combinations thereof; said copolymer curable with either (b) heat or radiation or said coating composition contains (c) curing component comprising at least one isocyanate group; or a carbodiimide compound; an aldehyde source, an amino resin, or combinations thereof optionally with heat; and (c) a carrier liquid. 
     
     
         30 . The aircraft motion control auxiliary power unit suspension system of  claim 27 , wherein said organic solvent is methyl acetate, n-butyl acetate, t-butyl acetate, acetone, ethyl acetate, isopropyl acetate, isobutyl acetate, tetrahydrofuran, n-methylpyrolidone, heptate, dimethylformamide, diisobutyl ketone, methyl isoamyl ketone, monochlorotoluene, naphtha, hexane, xylene, toluene, MEK, or MIBK. 
     
     
         31 . The aircraft motion control auxiliary power unit suspension system of  claim 17 , wherein said elastomeric polymer comprises an ambient temperature curable coating composition in a mixture of 2-parts providing a non-volatiles content of from 4% to 25% by weight, and comprising a part (A) which comprises an organic solvent and fluoroelastomer dissolved therein, said fluoroelastomer containing crosslinkable sites in quantitative amount according to an acid number of from 2 to 6 mg base per gram, and a part (B) which comprises an organosilane comprising hydrolysable groups and a mono primary amine, wherein said ratio of amine equivalents in part B to acid equivalents in part said A ranges from 3:1 to 12:1 and wherein a cured unsupported film from said coating exhibits at least 200% elongation. 
     
     
         32 . The aircraft motion control auxiliary power unit suspension system of  claim 14 , wherein the helical threaded portions of said first and second elastomeric rod ends each terminate with a stopper portion. 
     
     
         33 . An aircraft suspension system device, said aircraft suspension system device comprising:
 a first suspension linkage including a first and a second terminal end, each having a helical threaded portion of a same hand;   a first rod end having a helical threaded portion, said helical threaded portion of said first rod end having a hand corresponding to said helical threaded portion of said first terminal end of said first suspension linkage, said first rod end includes a non-threaded stopper portion disposed to prevent said suspension link from moving in a first direction when said helical threaded portion of said first terminal end meets said non-threaded stopper portion of said first rod end; and   a second rod end having a helical threaded portion, said helical threaded portion of said second rod end having a hand corresponding to said helical threaded portion of said second terminal end of said first suspension linkage, said second rod end includes a non-threaded stopper portion disposed to prevent said suspension link from moving in a second direction when said helical threaded portion of said second terminal end meets said non-threaded stopper portion of said second rod end, wherein said hand of said helical threaded portion of said first rod end and said hand of said second rod end is the same.   
     
     
         34 . The aircraft suspension system device of  claim 33 , wherein said helical threaded portions of said first and second rod ends are right-handed. 
     
     
         35 . The aircraft suspension system device of  claim 33 , wherein said helical threaded portions of said first and second rod ends are left-handed. 
     
     
         36 . The aircraft suspension system device of  claim 33 , wherein epoxy is applied to said helical threaded portions of said first and second rod ends during assembly. 
     
     
         37 . The aircraft suspension system device of  claim 33 , wherein said helical threaded portions of said first and second rod ends have a same pitch. 
     
     
         38 . The aircraft suspension system device of  claim 33 , wherein the helical threaded portions of said first and second elastomeric rod ends each have at least two transitional imperfect threads. 
     
     
         39 . The aircraft suspension system device of  claim 38 , wherein the at least two transitional imperfect threads have a gradually formed shallow depth. 
     
     
         40 . The aircraft suspension system device of  claim 38 , wherein the at least two transitional imperfect threads have a gradually altered pitch. 
     
     
         41 . The aircraft suspension system device of  claim 33 , wherein the helical threaded portions of said first and second elastomeric rod ends each terminate with a non-same-threaded stopper portion. 
     
     
         42 . The aircraft suspension system device of  claim 33 , wherein the helical threaded portions of said first and second elastomeric rod ends each transition into a non-same-threaded stopper portion having a difference in a thread characteristic. 
     
     
         43 . An aircraft suspension system device, said aircraft suspension system device comprising:
 a tubular rod linkage including a first and a second terminal end, each having a threaded portion of a same hand;   a first rod end having a threaded portion, said threaded portion of said first rod end having a hand corresponding to said threaded portion of said first terminal end of said linkage, said first rod end includes a non-same-threaded stopper portion disposed to prevent said linkage from moving in a first direction when said threaded portion of said first terminal end meets said non-same-threaded stopper portion of said first rod end; and   a second rod end having a threaded portion, said threaded portion of said second rod end having a hand corresponding to said threaded portion of said second terminal end of said linkage, said second rod end includes a non-same-threaded stopper portion disposed to prevent said linkage from moving in a second direction when said threaded portion of said second terminal end meets said non-same-threaded stopper portion of said second rod end, wherein said hand of said threaded portion of said first rod end and said hand of said second rod end is the same, with said first rod end connecting a first point and said second rod end connecting a distal second point at a linkage distance, said tubular rod linkage providing a linkage between said first point and said second point.   
     
     
         44 . An aircraft suspension system device, said aircraft suspension system device comprising:
 a first suspension linkage including a first and a second terminal end, each having a threaded portion of a same hand;   a first rod end having a threaded portion, said threaded portion of said first rod end having a hand corresponding to said threaded portion of said first terminal end of said first suspension linkage, said first rod end includes a non-same-threaded stopper portion disposed to prevent said suspension link from moving in a first direction when said threaded portion of said first terminal end meets said non-same-threaded stopper portion of said first rod end; and   a second rod end having a threaded portion, said threaded portion of said second rod end having a hand corresponding to said threaded portion of said second terminal end of said first suspension linkage, said second rod end includes a non-same-threaded stopper portion disposed to prevent said suspension link from moving in a second direction when said threaded portion of said second terminal end meets said non-same-threaded stopper portion of said second rod end, wherein said hand of said threaded portion of said first rod end and said hand of said second rod end is the same.