Patent Publication Number: US-2019178284-A1

Title: Interchangeable, debris insensitive and non-slipping reaction torque transfer system

Description:
RELATED APPLICATIONS 
     The present application is a continuation-in-part of U.S. application Ser. No. 16/150,633, filed Oct. 3, 2018, which is a continuation of U.S. application Ser. No. 14/932,768, filed Nov. 4, 2015, now U.S. Pat. No. 10,107,325, issued Oct. 23, 2018, both of which are incorporated herein by reference. The present application is also a continuation-in-part of International Application No. PCT/US18/34746, filed May 25, 2018, which claims priority to U.S. application Ser. No. 15/605,876, filed May 25, 2017, and to U.S. application Ser. No. 15/605,861, filed May 25, 2017, all of which are incorporated herein by reference. If any disclosures are incorporated herein by reference and such incorporated disclosures conflict in part or whole with the present disclosure, then to the extent of conflict, and/or broader disclosure, and/or broader definition of terms, the present disclosure controls. If such incorporated disclosures conflict in part or whole with one another, then to the extent of conflict, the later-dated disclosure controls. 
    
    
     FIELD OF THE INVENTION 
     The present invention relates to interchangeable systems and tools for transferring an actuation torque on an actuation receiving structure such as a nut and/or bolt head with varying size and/or shape while concentrically transferring a corresponding oppositely acting reaction torque onto an underneath base surface via an in between Belleville reaction washer with interchangeable configuration and functionality. 
     BACKGROUND 
     Reaction washers are increasingly employed to transfer onto a base surface underneath a reaction torque that is resulting from actuating a nut or bolt head resting on the reaction washer. Reaction washers are conveniently placed in between the nut and/or bolt head to be tightened and the flange surface. They bite into the underneath flange surface while the nut and/or bolt head is tightened by the applied actuation torque. The resulting reaction torque is thereby concentrically and without any distorting side loads transferred from the torque wrench housing onto the flange body. 
     In the prior art, actuation and reaction sockets are combined and fixed on the power torque wrench commonly via a number of small screws. In addition, at the time this invention was made, commercially available reaction washers provide only reaction torque transfer without any well-known washer functionality to secure nuts and/or bolt heads against unintentional loosening. Even worth and because the necessary tight fit of reaction torque transfer tools, the employment of additional safety washers is prohibitive together with prior art reaction washers and their respective tightening systems. Therefore, there exists a need for an interchangeable nut and/or bolt head actuation system that includes interchangeable and variably configured reaction washers including configurations with varying levels of securing against inadvertent loosening. The present invention addresses this need. 
     Also in the prior art and at the time this invention was made, commercially available reaction washers are only available in a fixed ratio between center hole and outside diameters, which limits the combination of varying nut and/or bolt head sizes and styles for given bolt thread diameters. The respective prior art actuation and reaction torque transfer tools provide limited interchangeability between reaction washer outside size and nut and/or bolt head size and style. Therefore, there exists a need for an interchangeable actuation and reaction torque transfer tool system that can be fast, easily and reliably adapted for varying reaction washer outside sizes and nut and/or bolt head sizes and styles. The present invention addresses also this need. 
     It is imperative for proper function of a reaction washer that it does not slip during the tightening phase during which the axial load and the reaction torque on the reaction washer ramp up from an initial minimum to the final tightening load of the nut and/or bolt head resting on the reaction washer. To meet this requirement, the slippage resistance in between the reaction washer bottom and the base surface has to be at any time higher than the friction in the respective actuated thread interface. To accomplish this in a flat surface contact with a base surface, the mean diameter of initial bottom serration contact with the base surface is desirably substantially more than 13.3% larger than the mean thread diameter. This is because common threads have about 60 degree thread flank angle resulting in a normal force on the thread flanks and the corresponding friction force to be at least 13.3% higher than in between a flat surface pair of similar configuration. Nevertheless, inadvertent contamination and/or corrosion in the thread interface and presence of lubricant, paint or other friction reducing elements on the base surface may occur in field conditions such that keeping an initial bottom serration contact radius to a maximum alone may not suffice. In a prior art of the present inventors, circumferentially arrayed bite spikes were introduced to provide initial bite into a base surface such that reaction torque transfer does not rely on surface friction alone but also on a form interlock between the spike tips and their respective indentations on the base surface. Although this proofs highly effective, there exists still a need for an initial bottom serration contact area that is at a minimum and at a maximum distance from the reaction washer axis while at the same time providing a gradual, radially inward progressing contact between the reaction washer bottom and the base surface during the respective tightening operation. The present invention addresses this need. 
     A prior art reaction washer of the present inventors may also provide some functionality to withhold the nut or bolt head from inadvertent loosening via a central Belleville portion of it. The collapsing and springily resistance of the central Belleville body is limited by the radial extension of it. In addition to well-known Belleville washer configuration suitable for static securing against 
     loosening of the nut and/or bolt head resting on it, there are also well-known dual washer stacks with a helical ramp interface in between them that provides dynamic securing loosening of the nut and/or bolt head resting on it. Therefore, there exists a need for a reaction washer and system with extended Belleville configuration that radially extends substantially into and overlaps with the radial extension of the bottom serrations and that is interchangeable with a dual reaction washer with a helical ramp interface between them. The present invention addresses also this need. 
     Reaction washers feature torque receiving structures placed at the washer circumference. To transfer the reaction torque from a reaction socket onto them, the reaction socket commonly features a drain interface on its bottom that couples in a torque transferring fashion with the torque receiving structures. To keep the coupling between reaction washer and reaction socket compact and within eventually very limited space available around the nut or bolt head to be tightened, it is desirable to have the drain interface and torque receive structures to snuggly fit. On the other hand and in case of a Belleville reaction washer being employed, the flattening of the Belleville washer during its axial loading may cause angular displacement around its periphery, which may adversely affect a snug fit between torque receiving structures and drain interface. In addition and in the eventual presence of debris and/or paint on or around the reaction washer&#39;s torque receiving structures, a snug fit of them with the drain interface may be impaired by such debris and/or paint. Therefore, there exists a need for a reaction washer and tightening system including drain interface and torque receiving structures that are configured to provide a snug fit that on one hand is insensitive to the displacement occurring during flattening of a Belleville reaction washer and on the other hand that provides clearance spacing to accommodate for debris and/or paint that is being pushed out of in between the torque receiving structures during their coupling with the drain interface. The present invention addresses also this need. 
     SUMMARY 
     An actuation and reaction socket tool system features a reaction coupling that is slid onto and eventually attached to a well-known spline flange of a power torque wrench prior to coupling with the drive shaft of the torque wrench an actuation socket that is mating the size and shape of a nut and/or bolt head to be tightened or loosened. Depending on the outside size of a reaction washer underneath that nut and/or bolt head, a reaction coupling of corresponding size is then selected and snapped onto the reaction socket via circumferentially arrayed and interlocking castles on both the reaction coupling and reaction socket. One or more lock plates spring loaded snaps into grooves on the inside of the castles and axially locks the reaction coupling with the reaction socket. At least one of the reaction coupling and reaction socket may be axially withheld by the central actuation socket via an optional well-known safety pin that has eventually previously been inserted into the actuation socket and the drive shaft during their coupling. That way, the entire reaction socket tool system may remain connected to the power torque wrench while the safety pin remains in place. To remove the tool from the power torque wrench, the reaction coupling and reaction socket may be first decoupled, which provides access again to the safety pin for its removal. Alternately and instead of employing the safety pin, the reaction coupling may be fixed onto the spline flange and the power torque wrench directly. In that case, the reaction and actuation sockets may be quick and easily replaced by merely actuation the lock plate(s). 
     Further part of the Interchangeable Nut and/or Bolt Head Actuation System may be interchangeable reaction washers with Belleville spring body and eventually additional dual washer configuration with helical ramp interfaces between them. The Belleville spring washer configuration includes radial serrations on its slightly conical bottom face and optionally on its top face as well. A narrow central serration free rim on washer top and bottom may prevent stress spikes in the serration grooves along the central washer hole during flattening of the reaction washer at full load. 
     During initial loading, a minimum serration contact ring on the reaction washer bottom is in a maximum distance to the washer axis and may be offset from an inner receive flange diameter by a clearance radius within which a clearance undercut may provide room to clear out eventual debris from in between the torque receive structures of the reaction washer&#39;s torque receive flange during coupling with the reaction socket. Inadvertent eventual increased friction in the tread interface as well as eventual friction reducing elements on the base surface such as paint, dust or lubricant are thereby counter acted and slippage between the reaction washer and the base surface is prevented. 
     The small initial serration contact area of only the peripheral ends of the bottom serrations causes a biting of them at an earliest moment of load increase during initial tightening thereby transitioning earliest on from a pure friction-based contact to a biting form contact. As the tightening load increases, the reaction washer continues to flatten out and the bottom serrations extend their bite into the base surface towards the washer axis and within the radial extension of the nut or bolt head contact area with the washer top. At a maximum tightening load, the reaction washer is substantially flattened out and eventual top serrations of the reaction washer bite into the nut and/or bolt head and assist together with the springily resistance of the Belleville shaped reaction washer in withholding it against becoming inadvertently loose. 
     Interchangeable with the monolithic reaction washer may be alternately employed a reaction washer in a stacked dual washer configuration with a conical ramp interface in between them. The conical multi ramp interface provides for a low height of the overall stack making the stacked dual reaction washer interchangeable with the monolithic reaction washer. At the same time the stacked dual washer configuration provides for a well-known functionality of a lock washer stack to most reliably secure a nut and/or bolt head against inadvertent loosening of it up to load regiments as are simulated in the well-known Junkers safety washer test. A serration top face on the top washer has preferably the same Belleville angle than the serration bottom face on the bottom washer such that both top and bottom washers flatten out simultaneously. The toroidal deformation experienced by both top and bottom washers is thereby synchronized across their conical ramp interface. 
     In both reaction washer configurations, a number of torque receiving structures are radially outward protruding arrayed along an outer circumference of the reaction washer and with their top substantially flush with the circumference of the conical serration top face. Their bottom is vertically offset from the conical serration bottom face to provide sufficient clearance to a base surface the reaction washer may be biting into while transferring a tightening load from an above nut or bolt head. During flattening of the reaction washer, the reaction washer experiences toroidal deformation causing the torque receiving structures to tilt upwards of about the same angle about which a radial washer cross section flattens. Torque receiving faces of the torque receiving structures are substantially radially oriented such that the angular deflection of the torque receive structures leaves their orientation substantially unaffected. Consequently, the contact with a drain interface of a reaction socket remains snug during deformation of the reaction socket between relaxed and flattened state and free of peak surface stresses. 
     As another favorable result of the substantially radially oriented torque receive faces, the reaction torque transfer from the torque transfer flanks of the drain interface onto the torque receiving faces is substantially free of radially acting forces, which in turn eliminates the need for a circumferentially continuous support around the drain interface. The torque inducing structures that provide the torque transfer flanks are consequently tapering downwards on their outside resulting in a wedge shape of them. This further reduces radial access space necessary to transfer the reaction torque onto the reaction washer and clears out eventual debris or paint that may cover the gaps between torque receiving structures. The radially outward open gaps between the torque inducing structures provide for a mostly outward ejection of the debris while the reaction socket is pushed down over the reaction torque receiving interface of the reaction washer. Eventually remaining debris may be radially inward displaced into the clearance undercut. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
         FIG. 1  is a first perspective cut down view of a first embodiment reaction washer that is supporting a nut above and that is resting on a base. Also shown is a bottom portion of a reaction socket circumferentially engaging with the reaction washer. 
         FIG. 2  is the first perspective cut down view of the reaction washer and reaction socket of  FIG. 1 . 
         FIG. 3  is a second perspective cut up view of the reaction washer and reaction socket of  FIG. 1 . 
         FIG. 4  is the first perspective cut down view of the reaction washer and base of  FIG. 1 . 
         FIG. 5  is the second perspective cut up view of the reaction washer of  FIG. 1 . 
         FIG. 6  is the first perspective cut down view of a second embodiment reaction washer stack that is supporting a nut above and that is resting on a base. Also shown is a bottom portion of a reaction socket circumferentially engaging with a bottom washer of the reaction washer stack. 
         FIG. 7  is the first perspective cut down view of the reaction washer and base of  FIG. 6 . 
         FIG. 8  is a third perspective exploded down view of the reaction washer of  FIG. 6 . 
         FIG. 9  is a fourth perspective exploded down view of the reaction washer of  FIG. 6 . 
         FIG. 10  is a frontal cut view of the preferred embodiment of the interchangeable actuation and reaction tool system in operational position. 
         FIG. 11  is a fifth perspective view of a reaction coupling of  FIG. 10 . 
         FIG. 12  is the fifth perspective view of the reaction coupling of  FIG. 11  with a snap lock cover removed. Tangent edges are not shown for clarity. 
         FIG. 13  is a sixth perspective view of a reaction socket of  FIG. 10 . 
     
    
    
     DETAILED DESCRIPTION 
     Referring to  FIGS. 1-5, 10  a reaction washer  10  of a first embodiment of the invention has a washer axis  10 A, a conical top face  13 , a conical bottom face  17  and a reaction torque receiving interface  23 . The washer axis  10 A may coincide with a reaction torque axis  100 A around which a reaction torque RT may be transferred onto the reaction torque receiving interface  23  via a drain interface  132  of a reaction socket  130 . The reaction torque RT may result from applying an oppositely acting actuation torque TL/TT as a tightening torque TT or a loosening torque TL on an actuation receiving structure  1  such as a nut or bolt head  1 . An actuation torque TT/TL may be applied by a well know torque wrench  90  via a well-known actuation socket  120  coupled to the actuation receiving structure  1 . Due to the thread pitch of the tightening thread  2 , the tightening torque TT may result during tightening in a rotation of the actuation receiving structure  1  and a sliding of the tightening thread  2  in a downward direction and increase from an initial load LI towards final tightening load LF onto base surface  7 . During loosening, the loosening torque TL may result of a sliding of the tightening thread  2  in loosening direction and the final tightening load LF being reduced again. 
     Loads LI and LF in between initial and final state are transferred via a load inducing face  3  at the bottom of the actuation receiving structure  2  onto a conical top face  13  of a reaction washer  10  or in case of the second embodiment of a top washer  55 . Top serrations  16  may be circumferentially arrayed on the conical top face  13  and a central serration free top rim  15  may be employed concentrically inside the conical top face  13 . In this case and due to a top Belleville angle  13 A, the central serration free top rim  15  may be slightly higher than the top serrations  16  such that during load transfer of a minimal load LI, the preferably planar load inducing face  3  may be resting on and sliding around the central serration free top rim  15  in an initial low resistance sliding contact. 
     During torque wrench tightening with actuation socket and reaction socket  130 , rotational resistance between the actuation receiving structure  1  and the reaction washer  10  or top washer  55  is of no substantial functional concern. During initial manual assembly and preloading up to the initial load LI to the contrary, rotational resistance between the actuation receiving structure  1  and the reaction washer  10  or top washer  55  may be of concern. Sliding of the bottom serrations  17  along the base surface  7  may cause material removal from the base surface  7  that may clog the bottom serrations  17  and impair their biting during the following torque wrench assisted tightening. Hence, the initial low resistance sliding contact may be favorably utilized during manual assembly of reaction washer  10  or reaction washer stack  55 ,  75  and actuation receiving structure  1  and eventual manual establishment of the initial load LI without need to manually hold the reaction washer  10  or reaction washer stack  55 ,  75  against inadvertent rotation and inadvertent clogging of the bottom serrations  17 . 
     Also referring to  FIG. 6  and once the actuation receiving structure  1 , the reaction washer  10  or reaction washer stack  55 ,  75  are assembled with washer holes  11 / 56 ,  76  being concentrically with respect to washer axis  10 A and torque transfer axis  100 A aligned with the base hole  8  and the tightening thread  2 , the conical top face  13  or central serration free top rim  15  may be loaded by the load inducing face  3 . A reaction socket  130  may be coupled via its drain interface  132  with a reaction torque receiving interface  23  of the reaction washer  10  or reaction washer stack  55 ,  75  and an actuation socket  120  coupled with the actuation receiving structure  1 . For clarity, omitted are in  FIG. 6  actuation socket  120  and well-known thread bolt against which the actuation receiving structure  1  in the depicted example of a nut  1  may be screwed on as is well known in the art. 
     The conical top face  13  may have a number of top serrations  16  that are circumferentially arrayed around the washer axis  10 A. The conical bottom face  17  features a number of bottom serrations  20  that are also circumferentially arrayed around the washer axis  10 A and that are radially inward extending from a bottom conical face circumference  18 . The reaction torque receiving interface  23  has a number of torque receive structures  25  that are radially outward protruding and circumferentially arrayed around the washer axis  10 A along an outer circumference of the reaction washer  10  and bottom washer  75 . 
     The reaction washer  10  may have preferably a cross section thickness  10 H that is substantially continuous in radial direction at least in between the conical top face  13  and conical bottom face  17 . A top Belleville angle  13 A of the top conical face  13  and a bottom Belleville angle  17 A of the bottom conical face  17  are generally in between 0.1 and 8 degrees such that upon an initial load LI received via load inducing face  3  on at least one of the conical top face  13  and a top central serration free rim  15 , substantially only an initial peripheral serration contact rim  21  of the bottom serrations  20  penetrates into a base surface  7 . Preferably, the Belleville angles  13 A,  17 A are in between 2 and 5 degrees. The base surface  6  is part of a base  5  and is underneath the reaction washer  10  and opposing the initial load LI. Upon increasing the initial load LI up to a final tightening load LF, the conical bottom face  17  is flattening out and the bottom serrations  20  are radially inward penetrating the base surface  6  up to a full load serration contact area  22 . 
     The torque receive structures  25  may be part of a reaction torque receiving flange  35  positioned along a peripheral circumference of the reaction washer  10  and may be extending radially outward the initial peripheral serration contact rim  21  by clearance radius  36 R. The reaction torque receiving flange  35  may have a flange top  39  and a flange bottom  40  with receive flange height  35 H and receive flange diameter  35 D. The flange top  39  may be substantially level with and adjacent to a first conical top face circumference  14 . The flange bottom  40  is recessed from and adjacent to a second conical bottom face circumference  18  by clearance height  36 H. Clearance radius  36 R and clearance height  36 H define a clearance undercut underneath the reaction torque receiving flange  35  that may serve to contain debris and/or displaced paint so that neither debris nor displace paint may impede the coupling of and snug fit between the reaction torque inducing structures  135  and the torque receiving structures  25 . The torque receive structures  25  may be extending in between the flange top  39  and flange bottom  40 . The torque receive structures  25  have torque receive faces  29  that are substantially radially inward oriented and aligned with the washer axis  10 A such that a reaction torque RT around the washer axis  10 A received by the torque receive faces  29  results in a contact force FC that is under consideration of well-known contact friction substantially free of any radial force component. 
     Part of a reaction torque drain system  100  and while the torque receiving interface  23  is coupled to a drain interface  132  of a reaction socket  130 , the torque receive faces  29  are oppositely substantially mating a number of torque transfer flanks  137  provided by reaction torque inducing structures  135  that are circumferentially arrayed around a bottom flange  149  of a reaction socket  130 . Since the contact force FC is substantially in circumferential direction and free of any radial force component in consideration of well-known contact friction, the reaction torque inducing structures  135  of the drain interface  132  may extend individually downward from the bottom flange  149  without need of any circumferentially continuous support structure. Moreover, the reaction torque inducing structures  135  may have outer faces  139  that are conically downward and radially inward tapered in direction away from the reaction socket  130 . As a favorable result, the drain interface  132  may be fitted with tight spaces around the reaction washer  10 . As another favorable result, the drain interface  132  may with the downward wedge shaped reaction torque inducing structures  135  may easily penetrate into eventual thick debris layers around the torque receiving interface  23  and in between the torque receive structures  25  and may be radially self-cleaning as debris may radially outward eject from in between the reaction torque inducing structures  135  and/or radially inward towards the clearance undercut  36 . Such debris may be present particularly when having to access a reaction torque receiving interface  23  that has been painted over or otherwise exposed to environmentally induced debris deposits. 
     The torque receive structures  25  are preferably offset from the conical bottom face  25  such that a hooking nose  141  extending from a distal end of the torque transfer flanks  137  is hooking in underneath the respective torque receive structures  25  immediately above and clear off the base surface  7  while the drain interface  132  is coupled and reaction torque RT transferring to the reaction torque receiving interface  23 . The hooking noses  141  may be extending from both transfer flanks  137  of the reaction torque inducing structures  135  so that they may hook underneath the torque receive structures  25  during application of a tightening torque TT or a loosening torque TL on the actuation receiving structure  1 . 
     The reaction washer  10  may further feature on its washer top  12  a central serration free top rim  15  and on its washer bottom  24  a central serration free bottom rim  19 . Central serration free top and bottom rims  15 ,  19  may provide for continuous stress levels that may be at a maximum around the washer hole  11  while the reaction washer  10  is flattened out and may eliminate peak stress areas in the grooves between the serrations  16 ,  20  along the most stress sensitive areas around the washer holes  11 ,  56 ,  76 . 
     Referring to  FIGS. 6-9  and a second embodiment of the invention, a reaction washer stack  50  may include a top washer  55  and a bottom washer  75  having a washer stack height  50 H. As shown in the  FIGS. 1, 6 , washer stack height  50 H may be similar to singe washer height  10 H such that monolithic reaction washer  10  may be interchangeable with reaction washer stack  50 . The top washer  55  provides thereby the conical top face  13  with preferably the top serrations  16 , whereas the bottom washer  75  provides the conical bottom face  17  with the bottom serrations  20 . A conical multi ramp interface  58  in between the top and bottom washers  55 ,  75  is provided by a first multi ramp cone  59  on the bottom of the top washer  55  and a second multi ramp cone  79  on the top of the bottom washer  75 . The first multi ramp cone  59  has a number of conical ramp faces  64  that are circumferentially arrayed and interposed by first ramp face steps  69  around the washer axis  10 A such that a cross section of the top washer  55  is outwards declining from an inner maximum top washer cross section thickness  55 CI towards an out outer top washer circumference  57 . There, the top washer  55  has a minimum top washer cross section height  55 CO. 
     The bottom washer  75  provides the reaction torque receiving interface  23 , preferably with the reaction torque receiving flange  35  and torque receiving structures  25 . The bottom washer  75  features also the conical bottom face  17  with the circumferentially arrayed bottom serrations  20  that are radially inward extending from the bottom conical face circumference  18 . On the top of the bottom washer  75  and oppositely mating the first multi ramp cone  59  is a second multi ramp cone  79  with its circumferentially arrayed second conical ramp faces  84  interposed by second ramp face steps  89 . That way, a cross section of the bottom washer  75  is outwards inclining from an inner bottom washer cross section thickness  75 CI towards the reaction torque receive interface. As another favorable result, the first multi ramp cone  59  is snug contacting and rotationally blocked by the second multi ramp cone  79  in a thread tightening direction TT and is helically free sliding against the second multi ramp cone  79  in a thread loosening direction TL. The conical multi ramp interface  58  has an interface cone angle  58 A in radial direction relative to the washer axis  10 A that defines the proportion between respective inner and outer cross section thicknesses  55 CI- 55 CO,  75 CI- 75 CO. The ramp faces  64 ,  84  have an interface ramp angle  58 RA in circumferential direction around the washer axis  10 A that defines the pitch of the conical multi ramp interface  58 . The interface ramp angle  58 RA is larger than the well-known thread pitch of the tightening thread  2  such that during inadvertent rotation of the actuation receiving structure  1  in loosening direction around the washer axis  10 A, the top washer  55  may be dragged along via its top serrations  16  biting into the load inducing face  3 . Consequently, the top washer  55  may ramp up against the bottom washer  75  more than the actuation receiving structure  1  may axially displace away from the base surface  7 . This self-tightening effect is highly effective in preventing the actuation receiving structure  1  to become loose even under most severe shear displacement as simulated in a well-known Junkers bolt tension test. Nevertheless and due to this self-tightening effect, actuation and reaction torque necessary to loosen an actuation receiving structure  1  resting on a reaction washer stack  50  may be up to above 30% higher than the previously applied tightening actuation and reaction torques. The substantially radial force free coupling between reaction torque inducing structures  135  and torque receiving structures  25  facilitates such extensive torque transfer requirements within a minimal outer reaction socket diameter  130 OD. 
     Reaction washer  10  and top and bottom washer  55 ,  75  may be made of well-known materials such as hardened steel suitable of providing sufficient hardness for the serrations  16 ,  20  to bite into common materials of actuation receiving structures  1  and bases  6  while at the same time providing sufficient resilience for the Belleville spring action of them. A reaction washer  10  or reaction washer stack  50  may be positioned with its hole  11 /( 56 ,  76 ) over a base hole  8  on a base surface  7 . Then the actuation receiving structure  1  such as a nut or bolt may be manually screwed on until the load inducing face  3  is in snug contact with either the conical top face  13  or the central serration free top rim  15  and an initial load LI is established. The reaction washer  10  or washer stack  50  do not slide with their bottom serrations  20  initial peripheral serration contact rim  21  in particular on the base surface  7  but penetrate already sufficiently into it during initial loading LI. As the reaction washer  10  or reaction washer stack  50  remains substantially in its natural shape thereby without any flattening and the bottom serrations  20  in the bottom Belleville angle  17 A to the base surface  7 , only their very outward end may contact and penetrate into the base surface  7  in a sharp point contact. All the sharp point contacts may circumferentially combine to the initial peripheral serration contact ring  21  that is in a maximum concentric distance around the washer axis  10  and has minimal contact area. Both of these criteria substantially contribute to a successful bite action of the bottom serrations  20  at initial load LI even across lubricant, or paint layers that may be present on the base surface  7 . 
     In a following step, a well-known torque wrench  90  is coupled to the actuation receiving structure  1  via an actuation socket  120  to induce rotation and is coupled with its housing  92  to the reaction torque receiving interface  23  via the reaction socket  130  to transfer and drain reaction torque RT as is taught in more detail below. While a tightening torque TT is applied to the actuation receiving structure  1  and it being screwed downward along the tightening thread  2 , the bottom serrations  20  free of debris bite unimpeded into the base surface  7  and drain the corresponding reaction torque RT received via the reaction torque receiving interface  23  into the base  6 . As the initial load LI ramps up to the final tightening load LF, the reaction washer  10  or reaction washer stack  50  flattens out and the bottom serrations  20  gradually bite radially inward towards the washer axis  10 A and directly underneath the load inducing face  3  for a straight axial transfer of the full tightening load LF onto the bottom serrations  20 . This results in maximum bite action and rotational resistance of the reaction washer  10  or reaction washer stack  55 ,  75 . Any eventual lubricant or paint layers may be thereby also gradually squeezed into the base hole  8  and/or clearance undercut  36  thereby maximizing bite of the bottom serrations  20  even in the eventual presence of lubricant or paint on the base surface  7 . 
     The flattening of the reaction washer  10  or reaction washer stack  50  introduces an angular upward displacement of the torque receive structures  25 . Due to the preferably substantially radial alignment of the torque receive faces  29 , the snug contact with torque transfer flanks  137  is maintained and thus surface peak stresses and destructive deformation and galling prevented during washer flattening. In case of the reaction washer stack  50 , the flattening of the top washer  55 ,  75  happens simultaneously and full functionality of the above described initial peripheral serration contact ring  21  is provided. Top and bottom Belleville angles  13 A and  17 A are preferably equal in particular in case of the second embodiment such that full load serration contact area  22  is provided while at the same time snug contact in the conical multi ramp interface  58  is maintained up to full load LF. 
     At full predetermined load LF, the eventual top serrations  16  bite into the load inducing face  3  such that the actuation receiving structure  1  is withheld by the reaction washer  10  or reaction washer stack  50  against inadvertent rotation in loosening direction. At the same time, the Belleville resilient load carrying of the reaction washer  10  or reaction washer stack  50 , the actuation receiving structure  1  is prevented from axially disengaging from the top serrations  16  in case of axial load vibrations or fluctuations as are well known in the art. In case of the reaction washer stack  50  additional safety against inadvertent loosening of the actuation receiving structure  1  even in cases of laterally induced displacement between base  6  and actuation receiving structure  1  is provided by the conical multi ramp interface  58 . At the same time, the reaction washer stack  50  is provided within a stack height  50 H that is similar to the reaction washer height  10 H, making them interchangeable. 
     To loosen the actuation receiving structure  1  again, the drain interface  132  may be reengaged with reaction torque receiving interface  23 . Any debris accumulated around the reaction torque receiving interface  23  or in between the torque receive structures  25  is displaced by the wedge-shaped reaction torque inducing structures  135  and radially outward ejected via the radially outward open gaps between them and/or radially inward pushed into the clearance recess  36 . Once reaction socket  130  and actuation socket  120  are coupled, a loosening torque TL is applied to a level such that the friction in the tightening thread  2  and between the load inducing face  3  and the conical top face  13  with its eventual biting top serrations  13  is overcome. In case of the reaction washer stack  50 , the loosening torque TL may be brought to a level such that the first conical ramp faces  64  fully slide around their respective second conical ramp faces  84  and plunge axially down over the ramp face steps  89  into the next following conical ramp face  84 , which may sufficiently stretch the thread bolt for it to become loose at that time. If not, then the actuation receiving structure  1  may be destructively removed by applying a loosening torque TL that exceeds the respective bolts structural limits. 
     As in  FIG. 10 , a torque transfer system  100  for concentrically and simultaneously transferring an actuation torque and a reaction torque around a torque transfer axis  10 A features an actuation socket  110 , a reaction coupling  120  and a reaction socket  130 . The actuation socket  110  may have a drive shaft torque interface  111 , an axial shaft lock interface  112 , an actuation interface  113  and an axial retention structure in the form of snap ring  115  and/or a circumferential retention face  116 . 
     In operational position, the actuation socket  110  is coupled with a drive shaft  95  of a torque wrench  90  via its drive shaft torque interface  111  that is correspondingly shaped and in a torque transferring mate with the contoured shape such as for example a square of the drive shaft  95  as is well known in the art. The actuation interface  113  such as for example but not limited to a hex, double hex, Torax™, triple square, is thereby positioned substantially centrally and concentrically with respect to the torque transfer axis  10 A and is facing away from the torque wrench  90  for transferring the actuation torque from the drive shaft  95  onto the actuation receiving structure  1  such as a nut and/or bolt head. 
     The actuation socket  110  may be axially coupled to the drive shaft  95  via an axial shaft lock interface in the preferred configuration of a lock pin  114  engaging with a radial through hole  112  that is radially extending through the body of the actuation socket  110  and a radial shaft hole  18  that is radially extending through the drive shaft  95 . The axial retention feature  115 / 116  is thereby axially positioned with respect to the torque wrench  90 . 
     The reaction coupling  120  has a torque wrench interface  125  and a reaction socket interface  126 . The torque wrench interface  125  may be in the preferred form of an internal spline  125  in a configuration that is mating preferably a spline flange  91  that may be part of a well-known housing  92  of the torque wrench  90 . The spline flange  91  may be positioned axially adjacent the drive shaft  95  and may be substantially concentric with respect to the torque transfer axis  10 A. The torque wrench interface  125  is torque transferring and may be axially slide able or axially fixed coupled with the housing  92  in general but preferably with the spline flange  91 . The reaction socket interface  126  becomes thereby positioned substantially concentric with respect to the torque transfer axis  10 A and is facing away from the torque wrench  90 . 
     The reaction socket  130  has a coupling interface  131  and a drain interface  132 . While the reaction socket  130  is rotationally move able with respect to and substantially concentric surrounding the actuation socket  110 , it is coupled with the reaction socket interface  126  via its coupling interface  131 . Thereby, the drain interface  132  is substantially concentrically surrounding and axially adjacent the actuation interface  113 . Consequently, the reaction torque is transferred from the housing  92  onto a reaction receiving structure  10  that may be positioned at least beneath but preferably also concentrically with respect to the torque transfer axis  10 A around the actuation receiving structure  1 . The reaction receiving structure  10  may be preferably a reaction washer  10 , which in turn may transfer the received reaction torque onto a base surface  7 . 
     As also shown in  FIG. 4  and in case of the axial retention structure  115  being the snap ring  115 , the reaction socket  130  may have an internal circumferential snap groove  133  in which a snap structure such as a snap ring  115  may snap in. Thereby, the reaction socket  130  may be axially secured with respect to the torque transfer axis  10 A and onto the actuation socket  110 . Snap structure access holes  1331  may radially extend through the body of the reaction socket  130  and may be circumferentially arrayed around the snap groove  133  to externally access and radially depress the snap ring  115 . That way, the reaction socket  130  may be removed again from the actuation socket  110 . The snap ring access holes  1331  may be threaded such that the radial inward displacement of the snap ring  115  may be accomplished by screwing in set screws or the like into the snap structure access holes  1331 . 
     The axial retention feature  116  may alternately be a circumferential retention face  116  that may be facing towards the torque wrench  90 . In that case, the reaction coupling  120  may have an axial stop face  1271 . The axial stop face  1271  may be resting against the circumferential retention face  116  while the actuation socket  110  is axially secured on the drive shaft  95  and the reaction coupling  120  is coupled via its torque wrench interface  125  with the spline flange  91  of the housing  92 . 
     The axial retention feature  114  may alternatively be provided by the radial lock pin  114  that may radially extend outside the radial pin hole  112  and underneath the axial stop face  1271  while assembled to axially secure the actuation socket  110  on the drive shaft  95 . In that case and as may be clear to anyone skilled in the art, the reaction coupling  120  may be axially secured on the housing  92  by the axial stop face  1271  resting against the lock pin  114 . 
     As further shown in  FIGS. 11, 12, 13 , the reaction socket interface  126  may be provided by a number of first castles  121  that are circumferentially arrayed at an end of the reaction coupling  120  and preferably radially dimensioned with a first outer castle array diameter  121 OD that matches substantially an outer reaction socket body diameter  130 OD. At the same time, the coupling interface  131  may be provided by a number of second castles  134  that are circumferentially arrayed at an end of the reaction socket  130  in mating opposition to the first castles  121 . Likewise, the second castles  134  may be preferably radially dimensioned with an inner castle array diameter  134 ID that matches substantially an inner reaction socket body diameter  130 ID and an outer castle array diameter that matches substantially an outer reaction socket body diameter  130 OD. Thereby, the coupling interface  131  is axially slide able and circumferentially interlocking with the reaction socket interface  126 . 
     Employment of first and second castles  121 ,  134  and radial dimensioning  121 OD,  134 ID,  134 OD of them in conjunction with the reaction socket body diameters  130 ID,  130 OD as well as the circumferentially opposite mating of first and second castles  121 ,  134  provides for a high structural strength and high transferable reaction torque from the reaction coupling  120  onto the reaction socket  130  while maintaining outer diameters  130 OD,  134 OD and inner diameters  130 ID,  134 ID substantially continuous all the way to the end of the reaction socket  130  including the coupling interface  131 . This is advantageous on one hand for assembling the reaction socket  130  over the actuation socket  110  and on the other hand for keeping a maximum outer diameter of reaction coupling  120 , reaction socket interface  126  and coupling interface  131  within the limits of reaction body diameters  130 ID,  130 OD. The reaction body diameters  130 ID,  130 OD may in turn be predetermined by structural needs for transferring a predetermined reaction torque within the reaction socket  130  body as may be clear to anyone skilled in the art. 
     First and second castles  121 ,  134  may have first and second internal recesses  122 ,  136  in the preferred configuration of first and second internal grooves  122 ,  136 . At the same time, the reaction socket interface  126  may have a radial lock feature  123  in the preferred configuration of a lock plate  123 . The preferably two lock plates  123  may be axially retained and radially slide able within the reaction socket  120  and in between a removable snap lock cover  127  and the reaction coupling body  1201 . The lock plates  123  may be spring loaded forced via lock plate load springs  1232  into the first and second internal grooves  122 ,  136  while the reaction socket interface  126  is coupled with the coupling interface  131 . Preferably, first and second internal grooves  122 ,  134  are axially with respect to the torque transfer axis  10 A substantially aligned with each other while the reaction socket interface  126  is coupled with the coupling interface  131  such that the lock plates  123  may be of continuous thickness in between first and second castles  121 ,  134 . The lock plates  123  thickness may preferably correspond to the axial height of the first and second internal grooves  122 ,  134 . 
     The lock plates  123  may have each an externally accessible actuator  124  that may be circumferentially aligned with a respective one reduced height castle  1212 . The actuator  124  is extending radially outward beyond the outer first and second outer castle array diameters  121 OD,  134 OD. Thereby, the reaction socket interface  126  may be coupled with the coupling interface  131  in any circumferential oppositely mating orientation to each other unimpeded by the actuators  124 . 
     The preferably two lock plates  123  are positioned rotationally symmetric with respect to the torque transfer axis  10 A such that the snap interlock between the reaction socket interface  126  and the coupling interface  131  is circumferentially evenly distributed between them. The lock plates  123  may be radially guided by lock plate guide pins  1231  as may be clear to anyone skilled in the art. The snap lock cover  127  may be held onto the reaction coupling body  1201  via cover screws  1272 . The snap lock cover  127  may also provide the axial stop face  1271 . The first inner castle array diameter  121  ID may be substantially reduced below the second inner castle array diameter  134 ID to provide sufficient radial depth of the first internal grooves  122  such that the lock plates  123  remain axially guided within them over their entire radial movement range. 
     The internal spline  125  may be provided by a spline ring  1251  axially attached at the end of the reaction coupling  120  that is opposite the reaction socket interface  126 . That way, the reaction coupling  120  may be conveniently adapted to different spline flanges  11 . 
     All parts of the concentric actuation and reaction torque transfer system  100  may be fabricated from steel or any other material suitable for transferring predetermined high torque loads. To apply an actuation torque to a predetermined actuation torque receiving structure  34  and to concurrently drain the corresponding reaction torque onto an axially adjacent reaction torque receiving structure in the preferred form of reaction washer  10  or reaction washer stack  50 , an actuation socket  110  and reaction socket  130  with correspondingly shaped actuation and drain interfaces  113 ,  132  are selected. A reaction coupling  120  may be initially coupled with the spline flange  91  followed by coupling the actuation socket  110  with the drive shaft  95 . 
     In case of actuation and reaction torque receiving structures  1 ,  10 / 50  having standardized shapes, a snap ring  115  may be employed and actuation and reaction socket  110 ,  130  may be selected as a preassembled set. In that case, actuation and reaction sockets  110 ,  130  may be together already while the actuation socket  110  is attached to the drive shaft  95 . Alternately and in case of non-standardized combination of shapes or sizes of actuation and reaction torque receiving structures  1 ,  10 / 50 , the reaction socket  130  may be interchangeably selected to match the reaction washer or reaction washer stack  10 / 50  and be consecutively slid over the actuation socket  110  following the preselection, coupling and attachment of the actuation socket  110  onto the drive shaft  95 . The reaction socket  130  may be rotationally oriented such that its second castles  134  face the gaps in between the first castles  121 . The reaction coupling  120  may be then axially slid along the spline flange  91  such that the reaction socket interface  126  engages with coupling interface  131 . During coupling, lock plate displacement chamfers  1341  along the inner top edges of the second castles  134  may force the lock plates  123  radially inward until they give way for the second castles  134  to bottom out in between the first castles  121 . At that moment, the second internal grooves  136  become aligned with the first internal grooves  122  and the lock plates  123  spring back and lock into both first and second internal grooves  122 ,  136 . Thereby, a direct axial lock is established between first and second castles  121 ,  136  across the lock plates  123 . 
     In case of an axial stop face  1271  being employed instead of a snap ring  115 , The axial stop face  1271  resting against the lock pin  114  or the circumferential retention face  116  may keep the reaction coupling  120  and attached reaction socket  130  axially on to the torque wrench  90 . The torque transfer system  100  is now ready to be put in position together with the attached torque wrench  90  over the predetermined actuation and reaction torque receiving structures  1 ,  10 / 50 . 
     To disassembly the reaction socket  130  again, the actuators  124  are externally accessed and manually depressed, whereby the lock plates  123  are moved radially inward and the second castles  136  axially released. While the actuators  124  are kept depressed, the reaction socket  130  may be separated from the reaction coupling  120  and in the following the actuation socket  110  may be removed from the torque wrench  90  without having to loosen any screws. In case the reaction coupling  120  is axially loose connected to the torque wrench housing  92 , it may be removed as well. In case the reaction coupling  120  is also axially connected to the torque wrench housing  92  via well-known means, it may serve to easily and fast connect interchangeably various sizes of actuation sockets  110  and/or reaction sockets  120  with the torque wrench  90  as should be clear from the above. 
     Irrespective the preferred employment of the ring snap coupling  140  including the reaction socket interface  126 , the coupling interface  131  and the radial lock feature  123  in conjunction with the concentric actuation and reaction torque transfer system  900 , the ring snap coupling  140  may be independently employed to provide coupling of any two structures  120 ,  130  as described for the reaction socket  120  and reaction socket  130 . The reaction socket interface  126  may thereby be any first coupling interface  126  at a first coupling end  128  of a first structure  120  and the coupling interface  131  may thereby be any second coupling interface  126  at a second coupling end  138  of a second structure  130 . 
     Accordingly, the scope of the present invention is set forth by the following claims and their legal equivalent: