BELLEVILLE WASHER NUT PLATE - European Patent Office - EP 3054175 B1
(19)*EP003054175B1*(11)EP 3 054 175 B1EUROPEAN PATENT SPECIFICATION(12)(45) Date of publication and mention(51) Int Cl.:F16B 37/04 (2006.01)of the grant of the patent:23.10.2019 Bulletin 2019/43(21) Application number: 16154032.3(22) Date of filing: 03.02.2016(54) BELLEVILLE WASHER NUT PLATETELLERFEDERMUTTERNPLATTEPLAQUE D’ÉCROU DE RONDELLE BELLEVILLE(84) Designated Contracting States:AL AT BE BG CH CY CZ DE DK EE ES FI FR GBGR HR HU IE IS IT LI LT LU LV MC MK MT NL NOPL PT RO RS SE SI SK SM TR(30) Priority: 03.02.2015 US 201514612453(43) Date of publication of application:10.08.2016 Bulletin 2016/32(73) Proprietor: United Technologies CorporationFarmington, CT 06032 (US)(72) Inventors: SLANEY, Brandon T.West Hartford, CT Connecticut 06107 (US) MARTINEZ, Jr., Gonzalo F.Stuart, FL Florida 34997 (US)(74) Representative: DehnsSt. Bride’s House10 Salisbury SquareLondon EC4Y 8JD (GB)(56) References cited:JP-A- 2002 138 797US-A1- 2006 188 357US-A- 4 940 377EP 3 054 175 B1 PETERS, Donald W.Colchester, CT Connecticut 06415 (US)Note: Within nine months of the publication of the mention of the grant of the European patent in the European PatentBulletin, any person may give notice to the European Patent Office of opposition to that patent, in accordance with theImplementing Regulations. Notice of opposition shall not be deemed to have been filed until the opposition fee has beenpaid. (Art. 99(1) European Patent Convention).Printed by Jouve, 75001 PARIS (FR)
1EP 3 054 175 B1DescriptionBACKGROUND[0001] The present disclosure relates to the field of nutplates, and more particularly to a nut plate assembly including a Belleville washer stack.[0002] A typical gas turbine engine operates in an extremely harsh environment characterized by very hightemperatures and vibrations. A conventional gas turbineengine includes a compressor for compressing enteringair, a combustor for mixing and burning the compressedgases that emerge from the compressor with fuel, a turbine for expanding the hot gases to generate thrust topropel the engine, and an exhaust nozzle for allowinghot gases to exit the engine. Thus, the exhaust nozzlemust accommodate extremely hot gases exiting the engine. Other considerations critical to engine design areavoiding air leakage and insulating certain engine components from exposure to hot gases.[0003] In certain areas exposed to these hot exhaustgases, specialized materials are used that can withstandhot temperatures. Such specialized materials, althoughespecially resistant to temperature, can be susceptibleto fracture or cracking when attachment means, such asbolt and nut assemblies, are placed under a high levelof torque.[0004] Additionally, a typical gas turbine engine alsoincludes many areas where access to a nut and bolt assembly is only available from one side of the assembly.A nut plate is often used to obviate the need to applytorque to the nut in order to engage the bolt with the nutin these problematic areas. JP 2002 138797 A disclosesa nut fitting structure having a spring, according to thepreamble of claim 1. US 4940377 discloses a laminatednut having a plurality of spring discs or spring washers.US 2006/0188357 discloses an apparatus for containinga nut on a bolt.SUMMARY510152025303540[0005] According to a first a first aspect, there is provided an apparatus according to claim 1.BRIEF DESCRIPTION OF THE DRAWINGS45[0006]FIG. 1A is a perspective view of a nut plate assembly.FIG. 1B is a perspective view of a nut plate assembly.FIG. 2A is an exploded perspective view of a nutplate assembly according to a second example.FIG. 2B is a perspective view of a nut plate assemblyaccording to a second example.FIG. 3A is an exploded elevation view of a nut plateassembly according to a third example.FIG. 3B is an elevation view of a nut plate assemblyaccording to a third example.505522FIG. 4A is an exploded elevation view of a nut plateassembly according to a fourth example.FIG. 4B is an elevation view of a nut plate assemblyaccording to a fourth example.FIG. 5A is an exploded perspective view of a nutplate assembly according to a fifth example.FIG. 5B is a perspective view of a nut plate assemblyaccording to a fifth example.FIG. 6A is a perspective view of a nut plate assemblyaccording to an embodiment of the invention.FIG. 6B is a cross-sectional view of a nut plate assembly according to an embodiment of the invention.FIG. 7 is a perspective view of a thermally insulatingexhaust panel.FIG. 8 is a perspective view of a nut plate assemblyaccording to another example.FIG. 9 is a cross-sectional view of the nut plate assembly according to another example.DETAILED DESCRIPTION[0007] In a gas turbine engine, Belleville washers canbe a useful tool to help prevent fracturing or cracking ofthe thermally specialized, and often times brittle, materials. Belleville washers can maintain a near constantspring rate during all engine operating conditions, regardless of the thermal expansion and contraction of engineelements, and during oscillations due to engine vibration.Combining Belleville washers with nut plates allow forthe use of Belleville washers in areas of the engine wherea constant spring rate of the nut plate is desired andwhere there is access only to the bolt side of the nut plateassembly.[0008] FIG. 1A is a perspective view of nut plate assembly 10A. Nut plate assembly 10A includes nut 11Aand nut plate 12A. Retention tabs 14A are integrally attached to and extend upward from nut plate 12A. Retention tabs 14A include retaining clips 16A located at a distalend of retention tabs 14A. Lateral retention tabs 18A alsoextend upward from nut plate 12A. FIG. 1A also includesspring assembly 20A. Spring assembly 20A consists ofBelleville washers 22A.[0009] Nut 11A is positioned on nut plate assembly 10Asuch that retention tabs 14A retain nut 11A to remain inclose proximity to nut plate 12A during both use and nonuse of nut plate assembly 10A. The configuration of nutplate assembly 10A allows for nut plate 12A to absorbtorque received by nut 11A when nut 11A is threadablyengaged with a bolt. Retention tabs 14A prevent nut 11Afrom twisting relative to nut plate 12a, therefore obviatingthe need for a user to manually secure, or apply torqueto, nut 11A when threadably engaging nut 11A with abolt. As will be shown in later examples, nut plate 12A isoften fastened to another element of the engine in orderto provide the structural stability necessary to absorb thetorque from nut 11A nut plate 12A.[0010] Belleville washers 22A are a type of spring element shaped like a regular washer, but also include a
3EP 3 054 175 B1frusto-conical shape. The frusto-conical shape of Belleville washers 22A provides a spring characteristic toBelleville washers 22A. The spring characteristic of Belleville washers 22A functions as a dampening elementand can be used to provide a pre-load force to a boltedjoint or bearing. Belleville washers 22A are also knownas spring washers, conical washers, conical springs, conical spring washers, coned-disc springs, Bellevillesprings, and/or cupped spring washers.[0011] FIG. 1B is a perspective view of a nut plate assembly. Nut plate assembly 10B includes nut 11B andnut plate 12B. Retention tabs 14B are integrally attachedto and extend upward from nut plate 12B. Retention tabs14B include retaining clips 16B located at a distal end ofretention tabs 14B. Retention tabs 18B also extend upward from nut plate 12B. Retention tabs 14B are positioned around a perimeter of nut 11B and retain nut 11Bby holding nut 11B in place with retaining clips 16B. Retention tabs 18B also retain nut 11B in place by inhibitinglateral motion of nut 11B relative to nut plate 12B. Retention tabs 14B also retain spring assembly 20B, consisting of Belleville washers 22B, in place relative to nutplate 12B.[0012] Spring assembly 20B can be made up of Belleville washers 22B or other types of spring-like elements,such as spring washer, conical springs, and other typesof non-coil flexible washers. Spring assembly 20B canconsist of one or multiple Belleville washers. Bellevillewashers 22B can be in series or parallel. The spring rateof spring assembly 20B can be tailored by the numberand configuration of Belleville washers 22B. Although thisexample shows four Belleville washers 22B, other combinations may include more or fewer Belleville washers22B oriented in similar or different directions as Bellevillewashers 22B shown in FIG 1B.[0013] The pre-load force on spring assembly 20B maybe adjusted by varying the size, quantity, and configuration of Belleville washers 22B. The size, quantity, andconfiguration of Belleville washers 22B are selected toprovide the necessary load required throughout engineoperation, while remaining in a linear spring resiliencyrange. The load provided by Belleville washers 22Btherefore remains consistent for all operating conditionsof the engine.[0014] The spring rate of spring assembly 20B is alsodetermined by factors such as the inner and outer diameters of Belleville washers 22B, as well as the conicalslant or slope of Belleville washers 22B. These factorscan be modified to tune the spring constant and amountof deflection of Belleville washers 22B. Additionally, thethickness and material of Belleville washers can be selected to achieve a desired spring rate of Belleville washers 22B.[0015] Configuring nut plate 12B to retain both nut 11Band spring assembly 20B allows for nut plate assembly10B to be sold and used as an inseparable assembly.The inseparability of nut plate assembly 10B preventsdisassembly and/or missasembly of Belleville washers5101520253035404550553422B during engine assembly and repair. If during assembly of Bellville washers 22B, Bellville washers 22B arenot ordered correctly, the spring rate of spring assembly20B will not be per the original design intent of springassembly 20B.[0016] Additionally, being a nut plate, nut plate 12Brequires no access from the nut side of nut plate assembly 10B, which is of particular advantage in those areasof the engine where access to both sides of nut plateassembly 10B would be limited.[0017] FIG. 2A is an exploded perspective view of nutplate assembly 24A according to a second example. Nutplate assembly 24A includes nut 26A, upper cage 28A,Belleville washers 34A, retaining ring 36A, lower cage38A, base 44A, and bolt 46A. Upper cage 28A includesupper cage arms 30A with upper cage arm distal ends32A located at the distal ends of upper cage arms 30A.Upper cage arm distal ends 32A extend radially outwardfrom upper cage 28A. Lower cage 38A includes lowercage arms 40A with lower cage arm distal ends 42A located at the distal ends of lower cage arms 40A. Lowercage arm distal ends 42A extend radially outward fromlower cage 34A. Retaining ring 36A is positioned between upper cage 28A and lower cage 34A. Retainingring 36A is positioned around and co-axial with Bellevillewashers 34A. The inner diameters of both upper cage28A and lower cage 38A are greater than the outer diameter of Belleville washers 34A such that when nut plateassembly 24A becomes assembled, Belleville washers34A will be retained within upper cage 28A and lowercage 38A.[0018] FIG. 2B is a perspective view of nut plate assembly 24B according to the second example. Nut plateassembly 24B includes an assembled version of nut plateassembly 24A seen in FIG. 2A. In FIG. 2B, upper cage28B is affixed to nut 24B and lower cage 34B is affixedto base 44B with fasteners, which can include rivets. Bolt46B extends through the middle of each of nut 24B, uppercage 28B, Belleville washers 34B, retaining ring 36B,lower cage 38B, and base 44B.[0019] Belleville washers 34B are retained within upper cage arms 30B and lower cage arms 40B. Uppercage arms 30B are positioned in the spacings betweenlower cage arms 40B, and lower cage arms 40B are positioned in the spacings between upper cage arms 30B.Upper cage arms 30B engage with retaining ring 36B byinterlocking upper cage arm distal ends 32B with retaining ring 36B. Upper cage arm distal ends 32B interlockwith retaining ring 36B by hooking underneath retainingring to prevent upper cage 28B from movement awayfrom retaining ring 36B. Lower cage arms 40B engagewith retaining ring 36B by interlocking lower cage armdistal ends 42B with retaining ring 36B. Lower cage armdistal ends 42B interlock with retaining ring 36B by hooking above retaining ring to prevent lower cage 38B frommovement away from retaining ring 36B.[0020] Bolt 46B is threadably engaged with nut 26B.When assembled, nut plate assembly 24B compresses
5EP 3 054 175 B1Belleville washers 34B and a specific spring rate of Belleville washers 34B can be selected. The spring rate ofBelleville washers 34B can be adjusted by either increasing or decreasing the amount of torque applied to bolt46B. As the torque applied to bolt 46B increases, Belleville washers 34B compress and increase the springrate of Belleville washers 34B. As the torque applied tobolt 46B decreases, Belleville washers 34B decompressand decrease the spring rate of Belleville washers 34B.[0021] FIG. 3A is an exploded elevation view of nutplate assembly 48A according to a third example. Nutplate assembly 48A includes nut 50A, upper cage 52A,Belleville washers 58A, lower cage 60A, base 66A, andbolt 68A. Upper cage 52A includes upper cage arms 54Awith upper cage arm distal ends 56A located at the distalends of upper cage arms 54A. Upper cage arm distalends 56A extend radially inward to upper cage 52A andform an acute angle with each of respective upper cagearms 54A. Lower cage 60A includes lower cage arms62A with lower cage arm distal ends 64A located at thedistal ends of lower cage arms 62A. Lower cage armdistal ends 44A extend radially inward to lower cage 60Aand form an acute angle with each of respective lowercage arms 62A. Upper cage 52A and lower cage 60Aare positioned around and co-axial with Belleville washers 58A. The inner diameters of both upper cage 52Aand lower cage 60A are greater than the outer diameterof Belleville washers 58A such that when nut plate assembly 48A becomes assembled, Belleville washers 58Awill be retained within upper cage 52A and lower cage60A.[0022] FIG. 3B is an elevation view of nut plate assembly 48B according to the third example. Nut plate assembly 48B includes an assembled version of nut plate assembly 48A seen in FIG. 3A. In FIG. 3B, upper cage 52Bis affixed to nut 50B and lower cage 60B is affixed tobase 66B with fasteners, which can include rivets. Bolt68B extends through the middle of each of nut 50B, uppercage 52B, Belleville washers 58B, lower cage 60B, andbase 66B.[0023] Belleville washers 58B are retained within upper cage arms 54B and lower cage arms 62B. Uppercage arms 54B engage with lower cage arms 62B byinterlocking upper cage arm distal ends 56B with lowercage arm distal ends 64A. Upper cage arm distal ends32B interlock with lower cage arm distal ends 64A byhooking upper cage arm distal ends 32B with lower cagearm distal ends 64A to prevent upper cage 52B frommovement away from lower cage 60B. The relative anglebetween respective upper cage arms 54B and uppercage arm distal ends 56B, as well as the relative anglebetween respective lower cage arms 62B and lower cagearm distal ends 64B, allows upper cage arm distal ends56B and lower cage arm distal ends 64A to clip into eachother to prevent each of upper cage 52B and lower cage60B from separating.[0024] The third example shown in FIG. 3B providesan example of spring rate that can be varied less than51015202530354045505546the example shown in FIGS. 2A-2B. Nut plate assembly48B contains a substantially constant spring rate because of the engagement interface between upper cage52B and lower cage 60B. Upper cage 52B and lowercage 60B are designed such that once a certain level ofspring rate is reached by Belleville washers 58B throughproviding torque to bolt 68B, upper cage arm distal ends56B and lower cage arm distal ends 64B will engageeach other to prevent nut assembly 48B from decompressing.[0025] FIG. 4A is an exploded elevation view of nutplate assembly 70A according to a fourth example. Nutplate assembly 70A includes nut 72A, Belleville washers74A, lower cage 76A, base 82A, and bolt 84A. Lowercage 76A includes lower cage arms 78A with lower cagearm distal ends 80A located at the distal ends of lowercage arms 78A. Lower cage arm distal ends 80A extendradially inward to lower cage 76A and form an acute anglewith each of respective lower cage arms 78A. Lower cage76A is positioned around and co-axial with Bellevillewashers 74A. The inner diameter of lower cage 76A isgreater than the outer diameter of Belleville washers 74Asuch that when nut plate assembly 70A becomes assembled, Belleville washers 74A will be retained within lowercage 76A.[0026] FIG. 4B is an elevation view of nut plate assembly 70B according to the fourth example. Nut plate assembly 70B includes an assembled version of nut plateassembly 70A seen in FIG. 4A. In FIG. 4B, lower cage76B is affixed to base 82B with an attachment means,which may include rivets, welds, adhesives, or other mechanical fasteners. Bolt 84B extends through the middleof each of nut 72A, Belleville washers 74B, lower cage76B, and base 682B.[0027] Belleville washers 74B are retained within lowercage arms 78B. Lower cage arms 78B engage with nut72B by clipping lower cage arm distal ends 80A onto nut72B. Lower cage arm distal ends 80A clip onto nut 72Bby hooking lower cage arm distal ends 80A with nut 72Bto prevent nut 72B from movement away from lower cage76B. The relative angle between respective lower cagearms 78B and lower cage arm distal ends 80B allowslower cage arm distal ends 80B to clip onto the edge ofnut 72B to prevent each of nut 72B and lower cage 76Bfrom separating.[0028] Nut plate assembly 70B contains a substantiallyconstant spring rate because of the engagement interface between nut 72B and lower cage 76B. Nut plateassembly 70B is designed such that once a certain levelof spring rate is reached by Belleville washers 74Bthrough providing torque to bolt 84B, nut 72B and lowercage arm distal ends 80 will engage each other to preventnut assembly 70B from decompressing.[0029] FIG. 5A is an exploded perspective view of nutplate assembly 86A according to a fifth example. Nutplate assembly 86A includes nut 88A, Belleville washers90A, lower cage 92A, and rivets 96A. Lower cage 92Aincludes lower cage arms 94A. Lower cage 92A is posi-
7EP 3 054 175 B1tioned around and co-axial with Belleville washers 90A.The inner diameter of lower cage 92A is greater than theouter diameter of Belleville washers 90A such that whennut plate assembly 86A becomes assembled, Bellevillewashers 90A will be retained within lower cage 92A. Nut88A includes holes 98A configured to receive rivets 96Aduring assembly of nut plate assembly 86A.[0030] FIG. 5B is a perspective view of nut plate assembly 86B according to the fifth example. Nut plate assembly 86B includes an assembled version of nut plateassembly 86A seen in FIG. 5A. Belleville washers 90Bare retained within lower cage arms 94B. In FIG. 5B,rivets 96B extends through holes 98B. Rivets 96B aresecured to nut 88B so as to mechanically fasten nut 88Band rivets 96B together. Once fastened, rivets 96B prevent nut 88B from movement away from lower cage 92B.[0031] Nut plate assembly 86B contains a substantiallyconstant spring rate because of the engagement interface between nut 88B and lower cage 92B. Nut plateassembly 86B is designed such that once a certain levelof spring rate is reached by Belleville washers 90B, rivets96B are riveted to attached nut 88B to rivets 96B to prevent nut assembly 86B from decompressing.[0032] FIG. 6A is a perspective view of nut plate assembly 100A according to an embodiment of the presentinvention. Nut assembly 100A includes Belleville washers 102A, nut 104A, lower cage 110A, backbone 118A,and liner 120A. Nut 104A includes nut arms 106A withnut retaining clips 108A. Lower cage 110A includes lowercage arms 112A with lower cage retaining clips 114A.Lower cage 110A also includes anti-rotation feature 116Awhich prevents nut 104A from twisting relative to backbone 118A.[0033] Belleville washers 102A are retained within lower cage arms 112A. Nut 104A engages with lower cagearms 112A by interlocking nut retaining clips 108A andlower cage retaining clips 114A. Nut retaining clips 108Ainterlock with lower cage retaining clips 114A by hookingnut retaining clips 108A with lower cage retaining clips114A to prevent nut 104A from movement away fromlower cage 110A. The relative angle between respectivenut arms 106A and nut retaining clips 108A, as well asthe relative angle between respective lower cage arms122A and lower cage retaining clips 114A, allows nutretaining clips 108A and lower cage retaining clips 114Ato clip into each other to prevent each of nut 104A andlower cage 110A from separating. This prevention in separation maintains retention of Belleville washers 102Awithin nut plate assembly 100A during assembly and disassembly of nut plate assembly 100A.[0034] Anti-rotation feature 116A of lower cage 110Aprevents nut 104A from twisting relative to backbone118A. This configuration allows torque to be transferredfrom a bolt (not shown in FIG. 6A) to nut 104A, then tolower cage 110A, and then into backbone 118A. Thistransfer of torque allows the bolt to be accessed and/orremoved from a hot side of liner 120A and still allow retention of Belleville washers in nut plate assembly 110A51015202530354045505558without having Belleville washers 102A getting lost in theengine upon removal of the bolt.[0035] FIG. 6B is a cross-sectional view of nut plateassembly 100B according to the embodiment. As compared to nut plate assembly 100A presented in FIG. 6A,nut plate assembly 100B includes stop 122B that extendsfrom nut 104B. The length of stop 122B is configured tocome into contact with lower cage 110B when a specificlevel of torque is applied to bolt 123B. Stop 122B preventsover-compression of Belleville washers 102B past a specific amount of compression designated by desired operating characteristics of nut plate assembly 100B. GapGs extends between a bottom edge of stop 122B and abase portion of lower cage 110B. Gap GS can be designed to allow stop 122B to contact lower cage 110Bbefore too high a torque is applied to Belleville washers102B.[0036] Lower cage 110B is fastened to backbone 118Band such forms of fastening may include the use of clinchnuts, clamps, rivets, bolts, welds, adhesives, and othervarious forms of mechanical and non-mechanical fasteners. In the present embodiment, a bottom part of lowercage 110B is clamped to backbone 118B. The bottompart of lower cage 110B has been deformed by a tool tofit in a hole extending through backbone 118B.[0037] FIG. 7 is a perspective view of exhaust panel124. Exhaust panel 124 includes flow path side 126, backstructure 128, and nut plate assemblies 130. Exhaustpanel 124 provides an example of a thermally insulatingexhaust panel that can be used in an exhaust system ofan engine. As mentioned above, depending on the design and materials of exhaust panel 124, the spring rateof nut plate assemblies 130 can be adjusted to accountfor fracturing and/or cracking thresholds of the materialsused for flow path side 126 and back structure 128. Exhaust panel 124 can be used as an engine componentincluded in a gas turbine engine or in other types of engines.[0038] FIG. 8 is a perspective view of nut plate assembly 132 according to another example. Nut plate assembly 132 includes nut 134, Belleville washers 136, base138, and rivets 140. Base 138 includes base retentiontabs 142 with retaining clips 144. Base 138 also includesholes 146 configured to receive rivets 140.[0039] Belleville washers 136 are retained within baseretention tabs 142. Base retention tabs 142 engage withnut 134 by clipping retaining clips 144 onto nut 134. Retaining clips 144 clip onto nut 134 by hooking retainingclips 144 with nut 134 to prevent nut 134 from movementaway from base 138. A 90 degree angle between baseretention tabs 142 and retaining clips 144 allows retainingclips 144 to attach onto the edge of nut 134 to preventeach of nut 134 and base 138 from separating.[0040] In this example, rivets 140 extend above thelateral edges of nut 134 preventing lateral movement ofnut 134 relative to base 138. Other permanent or semipermanent features extending from or affixed to base138 can also be used to inhibit movement of nut 134
9EP 3 054 175 B1relative to base 138.[0041] FIG. 9 is a cross-sectional view of nut plate assembly 148 according to another example. Nut plate assembly is representational of a cross-sectional view taken long 9-9 of one of nut plate assemblies 130 in FIG. 7.Nut plate assembly 148 provides an example of an installed nut plate assembly 132 from FIG. 8.[0042] Nut plate assembly 148 includes exhaust panel150, flow path side 152, back structure 154, bolt 156, nut158, Belleville washers 160, and base 162. Base 162includes base retention tabs 164 and rivets 166. Rivets166 are used to mechanically fasten base 162 to backstructure 154.[0043] Bolt 156 extends through each of flow path side152, back structure 154, base 162, Belleville washers160, and nut 158. Bolt 156 is threadably engaged withnut 158. Nut plate assembly 148 compresses Bellevillewashers 160. The spring rate of Belleville washers 160can be adjusted by either increasing or decreasing theamount of torque applied to bolt 156. As the torque applied to bolt 156 increases, Belleville washers 160 compress and increase the spring rate of Belleville washers160. As the torque applied to bolt 156 decreases, Belleville washers 160 decompress and decrease the springrate of Belleville washers 160.[0044] A specific spring rate of Belleville washers 160can be selected by varying the conical slant, inner diameter, outer diameter, material, and/or thickness of eachof Belleville washers 160. The spring rate of Bellevillewashers 160 can also be adjusted by situating Bellevillewashers 160 in any one of series, parallel, or in a combination of series and parallel configurations. Thenumber of washers included in Belleville washers 160can also be varied to adjust the spring rate of Bellevillewashers 160. Belleville washers 160 include two Belleville washers in a series relationship such that Bellevillewashers 160 face the opposite direction. The configuration of Belleville washers 160 could be changed to includea parallel relationship, where the individual washers ofBelleville washers 160 would face the same direction.Additionally, more than two individual washers could beincluded in Belleville washers 160, and could be configured in any one of series, parallel, or in a combination ofseries and parallel configurations.[0045] Exhaust panel 150 provides an additional example of a thermally insulating exhaust panel that canbe used in an exhaust system of an engine. As mentionedabove, depending on the design and materials of exhaustpanel 150, the spring rate of nut plate assembly 148 canbe adjusted to account for fracturing and/or crackingthresholds of the materials used for flow path side 152and back structure 154.[0046] While the disclosure has been described withreference to an exemplary embodiment(s), it will be understood by those skilled in the art that various changesmay be made and equivalents may be substituted forelements thereof without departing from the scope of thedisclosure. For example, any of the spring assembles51010discussed herein can optionally include a smaller or larger number of Belleville washers, as well as varying orientations of the Belleville washers so as to vary the performance characteristics of the nut plate assembly. Inaddition, many modifications may be made to adapt aparticular situation or material to the teachings of the disclosure without departing from the essential scope thereof. Therefore, it is intended that the disclosure not belimited to the particular embodiment(s) disclosed, but thatthe disclosure will include all embodiments falling withinthe scope of the appended claims.Claims151.An apparatus comprising:a nut plate (12A);a plurality of retention tabs (14A, 14B) integrallyattached to the nut plate;a spring assembly (20A) contained within theplurality of retention tabs (14A),wherein the spring assembly comprises at leastone Belleville washer; anda nut (104A, 104B) retained by the plurality ofretention tabs, and characterized in that thespring assembly (20A) is located between thenut and the nut plate;the apparatus further comprising a bolt containing a threaded portion, wherein the bolt extendsthrough each of the nut plate, the spring assembly, and the nut, and further wherein the bolt isthreadably engageable with the nut, the apparatus further comprising a stop (122B) extendingfrom the nut (104B), wherein the length of thestop is configured to touch the nut plate (12A)when a specific level of torque is applied to thebolt, and further wherein the stop prevents overcompression of the spring assembly past a specific amount of compression.20253035402.The apparatus of claim 1, wherein the spring assembly (20A) comprises a plurality of Belleville washers(102A, 102B).3.The apparatus of claim 1, wherein the retention tabs(14A) include a first set of retaining clips that engagewith the nut.4.The apparatus of claim 3, wherein the nut includesa second set of retaining clips that engage with thefirst set of retaining clips.5.The apparatus of claim 1, wherein the nut plate (12A)includes a base mechanically fastened to an enginecomponent.6.The apparatus of claim 5, wherein the engine com-4550556
11EP 3 054 175 B1Revendicationsponent includes an exhaust panel of a gas turbineengine.Patentansprüche1.2.3.1.Vorrichtung nach Anspruch 1, wobei die Federanordnung (20A) eine Vielzahl von Tellerfedern (102A,102B) umfasst.10152025302.Appareil selon la revendication 1, dans lequel l’ensem
example shows four Belleville washers 22B, other com-binations may include more or fewer Belleville washers 22B oriented in similar or different directions as Belleville washers 22B shown in FIG 1B. [0013] Thepr e-oad l force onspr ing assembly20B may be adjusted by varying the size, quantity, and configura-tion of Belleville washers 22B. The .
Belleville. NamedNamedfor Julian F. Belleville who received a British patent in the 1860's. (It was on a valve application) Belleville Springs for Valve Live Loading. Belleville Springs, Belleville Disc Springs, Disc Springs and Conical Compression Washers are all names for the same type of spring.
Lock Washer and Washer Sheet Metal Screw and Washer Rear Bracket Rear Bracket Mounting Stud M6-1.0 Nut and Washer NOTE: Press tape should cover all metal portions of the #10 fitting. M8-1.25 x 15mm Bolt, Lock Washer, Washer & Nut M8-1.25 x 15mm Bolt, Lock Washer, Washer & Nut M8-
8 mm WASHER 8 25 mm BOLT 8 mm FLANGE NUT BOLTL 9. Loosely install a striker pin to the left striker bracket using a 10 mm Belleville washer and 10 mm nylock nut. NOTE: Tighten hardware snug for later adjustment (not fully torqued). 10 mm NYLOCK NUT 10 mm BELLEVILLE WASHER BRACKET STR
12 14 16 18 200 400 600 800 1000 1200 1400 1600 1800 2000 TEC Series Washer Split Lock Washer Mechanical Lock Nut Nylon Insert Nut Hex Nut, No Washer Hex Nut, Flat Washer Clamp Load (kN) Cycles 0 2 4 6 8 10 12 14 16 18 200 400 600 800 1000 1200 1400 1600 1800 2000 TEC Series Washer Split Loc
BELLEVILLE SPRING WASHERS B E L L E V I L L E S P R I N G W A S H E R S 226 leespring.com Call: 888-SPRINGS (888-777-4647) Fax: 888-426-6655 ID Represents the washer inside diameter. This is a minimum measurement and reflects the bolt size that the washer will accommodate. t Represents the washer material thickness as well as the washer solid (fl
Two techniques are described for insertion of nuts and washers, "nut-over-screw" technique and "nut-over-drill bit" technique. Optional Nut and Washer Technique 14 mm Screw with Nut Screw with Washer Nut with Washer 12 mm 3 mm 6.5 mm 15 mm Insuffi cient insertion depth between nut and nail.
INSTALLATION Belleville springs must be utilized correctly in order to maximize their benefit. There are several important points when using Belleville springs in a bolting application. A. Be sure that the bolts are long enough to account for the thickness of the Belleville. B. The
The API also provides the user with ability to perform simple processing on measurements made by the CTSU for each channel and then treat each channel as a Touch Button, or group channels and use them as linear or circular sliders. The API inherently depends on the user to provide valid configuration values for each Special Function Register (SFR) of the CTSU. The user should obtain these .
