Patent Publication Number: US-6336264-B1

Title: Method and apparatus for loosening and removing connection bolts

Description:
PRIORITY CLAIM 
     This application is based on and claims the priority under 35 U.S.C. §119 of German Patent Application 199 06 126.2, filed on Feb. 13, 1999, the entire disclosure of which is incorporated herein by reference. 
     FIELD OF THE INVENTION 
     The invention relates to a method and an apparatus for loosening and removing a tightly connected bolt arrangement that secures two structural components together, for example, the structural surface panels of an aircraft. 
     BACKGROUND INFORMATION 
     It is common in the field of aircraft construction, and also in the construction of other vehicles and various structural assemblies, to use connection bolts to connect or secure together plural structural components with each other. For example, the surface structural components such as fuselage panels of an aircraft are typically connected together by such connection bolt arrangements. Each connection bolt arrangement includes a connection bolt or stud arranged within an expansion sleeve. This connection bolt arrangement passes through a bored hole in the two structural components that are to be connected together. Due to a wedge-shaped or conical configuration of the exterior of the connection bolt and the interior of the expansion sleeve, a tight wedging or clamping effect between the connection bolt and the expansion sleeve, and between the expansion sleeve and the two structural components, is achieved when the connection bolt is driven into the expansion sleeve. 
     Thereby, the wedging effect causes the connection bolt to be tightly held in the expansion sleeve in a force-locking or pressure-locking manner. The terms “force-locking” or “pressure-locking” herein relate to a frictional contact and connection that does not involve a positive form-locking connection. Furthermore, the connection bolt may be threaded or otherwise configured to provide an additional degree of connection between the connection bolt and the expansion sleeve. The term “bolt” throughout this specification is not limited to a threaded bolt, but instead also encompasses an unthreaded bolt or stud or pin. 
     Once the above described type of connection is established, it is considered to be a substantially permanent connection. Nonetheless, occasionally such connections need to be loosened and removed in order to disassemble the two connected structural components, for example if an assembly error or defect has been discovered. A tool known as a so-called “big C” in the field of aircraft construction has traditionally been used for releasing such expansion bolt connections of mutually secured surface panels of an aircraft. Such a tool is particularly exemplified by tool No. 98 D 55307530 sold by DLH Frankfurt, Federal Republic of Germany. This tool generally consists of a C-shaped planar body with a hand-operated spindle drive mechanism, and generally operates according to the principle of a C-shaped screw clamp or C-clamp. This tool releases the above described bolt connection solely by applying a compression force against the expansion sleeve and the connection bolt that is force-locked therein, whereby this compression force is applied by the threaded spindle of the tool in the axial direction of the spindle. The required compression force is generated solely by a rotational moment or torque that is manually applied to the spindle mechanism. This is disadvantageous in view of the very high applied compression forces that are necessary for releasing such bolt connections. 
     A further disadvantage is that the tool is relatively large, cumbersome, and heavy, and cannot be disassembled into individual parts for transport and storage, whereby these parts can then be reassembled to form the complete tool at the worksite for example. Thus, the known tool must always be transported, stored, handled, and used at its final utilization location in its complete cumbersome configuration. Due to the high weight and large size of the tool, it is necessary to use great care in preparing the disassembly site at which the bolt connection is to be removed, and several people are required for handling the tool and mounting it at the work location. A single person is barely or not at all able to handle the so-called “big C”, and even then only with great physical effort. In practice, it is often the case that several attempts of applying the compressive force to the bolt connection are necessary for ultimately releasing the bolt, whereupon the bolt then suddenly is released in a sudden impact or jump-like manner. It is thus not possible to avoid the situation that the large heavy tool falls down when the connection is suddenly released, whereupon injuries to the workers and damage of the structural components can arise. 
     A further shortcoming of the known tool is that the spindle drive mechanism suffers great wear due to the extreme compression loads that must be applied to the bolt connection each time such a connection is to be released. Since the entire required release force must be generated by the rotation of the spindle drive, the spindle threading and the like are subjected to wear. 
     The technological background in the present context of removing such bolt connections is also exemplified by the disclosures of U. S. Pat. No. 3,237,291, and German Patent Publications DE-AS 1 300 471, DE 198 03 732 A1, and DE 44 34 152. While these patent publications disclose the general background or state of the art in this field, they do not disclose a tool and a method for removing connection bolts of the above described kind, which are able to overcome the above mentioned disadvantages of the prior art. 
     SUMMARY OF THE INVENTION 
     In view of the above, it is an object of the invention to provide a method and an apparatus for loosening and removing, or generally releasing, connection bolt arrangements that mechanically secure two or more structural components to each other. More particularly, it is an object of the invention to provide such an apparatus and a method, whereby the required forces are not entirely manually applied, and particularly are not entirely applied by a single torque applied to a single rotatable spindle. The invention further aims to minimize the likelihood of damage being caused to the structural components during the operation of mounting the apparatus, releasing the bolt connection, and then de-mounting the apparatus from the structural components. The degree of wear of the parts of the apparatus is to be reduced. The effort involved in releasing such bolt connections as well as the danger of injuries and the like are to be reduced or minimized through the invention, while also making the apparatus more easily handleable, storable, and transportable. The invention further aims to avoid or overcome the disadvantages of the prior art, and to achieve additional advantages, as are apparent from the present specification. 
     The above objects have been achieved in an apparatus or tool for releasing a connection bolt arrangement that includes a connection bolt fitted into an expansion sleeve, and that mechanically secures together at least two structural components. The apparatus includes two levers that are pivotally connected to each other, and a stamping actuator arranged between the two levers to apply a stamping force to the levers and thereby cause the levers to pivot relative to each other about the pivot joint connecting the two levers. 
     A first one of the levers has an opening or recess therein, with dimensions adapted to the outer dimension of a protruding end of the expansion sleeve, and to the outer dimension of an end of the connection bolt received in the protruding end of the expansion sleeve, so that the end surface of the expansion bolt is received in the recess and rests against a support shoulder thereof, while the connection bolt can freely move into the opening at the center of the recess in the first lever. The second lever has a pressing block that is configured and adapted to receive and press against a bolt head end or narrower tapered end of the connection bolt without pressing against the expansion sleeve. Thereby, a force applied by the stamping actuator is transferred through the two levers to apply respective pressing forces to the connection bolt and the expansion sleeve in such opposite directions and in such a manner to tend to push the connection bolt out of the expansion sleeve and thereby release the bolt from the sleeve. 
     Furthermore, a pulling extraction device is mounted on the first lever so as to engage the larger-diameter end of the connection bolt and apply a pulling or tension force to the connection bolt relative to the first lever, whereby this pulling force further tends to pull the connection bolt out of the expansion sleeve. The combination of the pulling force and the pushing forces applied to the connection bolt arrangement release the frictional or force-locked engagement of the bolt in the expansion sleeve, and move the bolt at least partially out of the sleeve. Thereafter, the tool is removed from the connection bolt arrangement and the released bolt arrangement can be removed from the structural components that it was securing. 
     The above objects have further been achieved according to the invention in a method of releasing a connection bolt arrangement including a connection bolt fitted into an expansion sleeve. This method is carried out using a tool that has two levers pivotally connected to each other and a pulling extraction device mounted on one of the levers. According to this method, the levers are pivoted relative to each other about a pivot joint so that the first lever pushes against the expansion sleeve in a first direction, while the second lever pushes against the connection bolt in a second direction opposite the first direction. Thus, the pushing forces applied by the first and second levers to the connection bolt arrangement have a tendency, or are applied in a direction, to push the connection bolt out of the expansion sleeve. Moreover, the method further includes applying a pulling tension force to a first end of the bolt relative to the first lever using the pulling extraction device, This pulling force tends to pull the connection bolt out of the expansion sleeve. The combination of the pushing forces applied by the levers and the pulling force applied by the pulling extraction device finally releases the connection bolt from the expansion sleeve, so that the bolt and sleeve may be removed from the structural components that were being mechanically connected by the connection bolt arrangement. 
    
    
     BRIEF DESCRIPTION OF THE DRAWINGS 
     In order that the invention may be clearly understood, it will now be described in connection with example embodiments, with reference to the accompanying drawings, wherein: 
     FIG. 1 shows the apparatus according to the invention for releasing connection bolt arrangements, by itself, i.e. not mounted on a connection bolt arrangement that is to be released; 
     FIG. 1A shows a side view of interengaged forked or pronged members of the apparatus of claim  1 ; 
     FIG. 2 shows the apparatus according to FIG. 1, further arranged in combination with or mounted on a connection bolt arrangement that is to be released, wherein some portions of FIG. 2 are shown in section; 
     FIG. 2A is a detail view of the detail portion IIA shown in FIG. 2; and 
     FIG. 3 shows an alternative embodiment with two pivot axes. 
    
    
     DETAILED DESCRIPTION OF PREFERRED EXAMPLE EMBODIMENTS AND OF THE BEST MODE OF THE INVENTION 
     FIG. 1 shows a tool or apparatus according to the invention, which is made up of a number of individual parts or components that can be assembled together to form the tool or disassembled as needed for convenient storage and transport of the apparatus. Thus, the various parts form a kit that can be assembled as needed to form the completed tool. The tool comprises a first lever member  1  and a second lever member  2 , which each have a generally rectangular shape with cut-outs or openings  25  to provide a reduced weight with good structural strength and rigidity of the levers  1  and  2 . In this detailed description, the lever members will be called simply “levers  1  and  2 ” for brevity. However, it should be understood that each overall “lever” can be regarded as an assembled combination of several components. For example, a “first lever” may include the first lever member  1 , with a forked body or pronged body  4 , and a mounting fixture block  7  assembled thereon, while a “second lever” may include the second lever member  2 , with a forked body or pronged body  6 , a mounting fixture block  12 , and a pressing block  8  assembled thereon. The details of the several individual components will be described in detail in the following. 
     As shown in FIG. 1, the levers  1  and  2  are in a generally horizontal or parallel position and respectively have inner side surfaces  11  and  21  that face each other. In this context, the phrase “substantially horizontal or parallel position” refers to a general position that allows a certain degree of mobility in view of the intended pivotal connection between the two levers in an angular range of ±5° from the parallel position shown in FIG.  1 . Also, since the tool or apparatus is a manually portable and useable tool, it can of course be arranged in various orientations as needed, and is not limited to an exactly horizontal arrangement of the levers  1  and  2 . More accurately, in other words, the illustrated embodiment involves the levers  1  and  2  being “substantially parallel” within the range of pivotal motion of ±5° as mentioned above. 
     The two levers  1  and  2  are pivotally connected to each other by a pivot joint arrangement, which includes, in this embodiment, two pivot links or forked or pronged bodies  4  and  6  and a pivot pin or joint  13  which pivotally connects these forked or pronged bodies  4  and  6  to each other. Each one of the forked or pronged bodies  4  and  6  has a respective one-pronged or two-pronged or multi-pronged fork at one end thereof and a protruding bolt at the other end thereof, whereby the fork and the protruding bolt extend along the basic body axis of the forked body. The two forked ends of the two forked bodies  4  and  6  are overlappingly engaged or intermeshed with each other, and the pivot pin  13  passes through a hole through the forked ends so as to pivotally interconnect the forked ends to each other. The pivot pin may be secured by a cotter pin or a clevis pin or the like at its end opposite its head. This arrangement is schematically shown in the side view of FIG.  1 A. 
     The protruding bolt at the opposite end of each forked body passes through a bored hole through the levers  1  and  2  respectively, generally near the middle of the length of each lever  1  and  2  in the present embodiment. In alternative embodiments, the forked bodies  4  and  6  may be arranged closer to one end than the other of each lever  1 ,  2 , or even directly at one end of each lever  1 ,  2  (whereby the actuator as described below is arranged along the middle portion of the length of the levers), in order to achieve different force transmission or lever arm ratios of the tool. In any event, the main body portion of each forked body  4  and  6  rests against the inner side surface  11 ,  21  of the levers  1 ,  2  in a T-butt manner. Then, a threaded nut  3  is tightened onto the free end of the protruding bolt of each forked body  4 ,  6 , whereby the nut  3  is tightened against the outer side surfaces  111 ,  211  of the levers  1 ,  2  respectively. Such an arrangement of forked bodies  4  and  6  provides a single pivot axis coincident with the pivot pin  13 . Alternative embodiments are possible. For example, the two levers  1  and  2  can be interconnected by two parallel cross-connect plates with the levers received therebetween, whereby a respective pivot pin connects each lever respectively to the plates. Thus, each lever would have its own associated pivot pin connecting it to the two plates, so that the apparatus would have two pivot axes, for example as shown in FIG.  3 . Another alternative involves a single cross-connect plate, whereby each lever is made up of two plates which receive rtte the respective end of the cross-connect plate therebetween. A respective pivot pin connects each lever to the respective opposite ends of the cross-connect plate. 
     As further shown in the embodiment of FIG. 1, a mounting fixture block  12  having a generally cylindrical configuration is secured onto the inner side surface  21  of the second lever  2  near the right end or “actuated end” E 21  thereof by a holding bolt  14  passing through the second lever  2 . Any known configuration of the bolt  14  can be used for securing the mounting fixture block  12 . For example, the bolt  14  may protrude from the block  12  and engage an internal threading in a through-bore of the lever  2  with an external threading of the bolt  14 . Alternatively, a head of the bolt  14  may be supported against the outer surface  211  of the lever  2 , while the block  12  is threaded onto an end of the bolt  14 . 
     A pressing block or pressing member  8  is mounted and secured on the inner side surface  21  of the second lever  2  near the left end or “free end” or “working end” E 22  thereof, whereby the securing is achieved in a similar fashion as for the mounting fixture block  12  or the forked body  6 . In the specific embodiment shown in FIG. 1, the protruding bolt of the pressing block  8  that passes through the second lever  2  has an internally threaded blind hole in the free end thereof, and a threaded screw  10  is threaded into this blind hole, so that the head of the screw  10  tightly presses against the outer side surface  211  of the lever  2 , preferably with a washer  9  therebetween, so as to secure the pressing block  8  tightly against the inner side surface  21  of the lever  2 . 
     In a similar manner as the above mentioned mounting fixture block  12  and/or the above mentioned pressing block  8 , another mounting fixture block  7  is secured to the first lever  1  near the right end or “actuated end” E 11  thereof. Particularly in the illustrated embodiment, the mounting fixture block  7  is secured with a screw (not shown) screwed into an internally threaded blind hole in an end of a protruding bolt of the mounting fixture block  7  that extends through a bore hole in the lever  1 , in a manner similar to the securing of the above described pressing block  8 . The screw is tightened until the mounting fixture block  7  is pulled tightly against the inner surface  11  of the first lever  1 . 
     A generally cylindrical first recess  22  in the manner of a shallow bored hole is provided in the inner side surface  11  of the first lever  1  near the left end or “free end” or “working end” E 12  thereof. A second recess  221  adjoins the first recess  22 . The second recess  221  has a greater depth as measured from the inner side surface  11 , but a smaller diameter than the first recess  22 . The second recess  221  also generally has the form of a shallow bored hole, coaxial with the first recess  22 . This combination of the first recess  22  and the second recess  221  forms a first step or support shoulder  22 A and a second step or support shoulder  221 A, which are significant for the operation of the tool as will be described below. Furthermore, coaxially with the first recess  22  and the second recess  221 , a through-going bore B 1  extends from the recesses  22  and  221  entirely through the lever  1  to the outer side surface  111  thereof. 
     Referring now to FIG. 2, further components of the apparatus are illustrated and will be described, in order to complete the tool. Specifically, at the right ends E 11  and E 21  of the levers  1  and  2 , a stamping actuator  17  is arranged between the two mounting fixture blocks  7  and  12  at a location displaced or offset from the pivot axis defined by the pivot pin  13 , and a pulling extraction device  24  is arranged in the bored hole B 1  near the left end E 12  of the first lever  1 . It should also be understood that the levers  1  and  2  can alternatively be pivotally connected by the pivot joint arrangement  5  positioned at one end of each lever, while the stamping actuator  17  is arranged more centrally along the length of the levers In any event, the position of the various components is selected to achieve the required balance of a force transmission ratio based on the operative lever arm lengths, in comparison to the stroke distance transmission ratio which also depends on the operative lever arm lengths. 
     The stamping actuator  17  will apply pressing forces or actuating forces FDS 1  and FDS 2  through the mounting fixture blocks  12  and  7  into the second lever  2  and first lever  1  respectively at the first ends E 21  and E 11  thereof. Thereby, the levers  1  and  2  will be caused to pivot about the pivot pin or joint  13 , thus applying transmitted pressing forces FDS 1 ′ and FDS 2 ′ from the second ends E 12  and E 22  of the levers  1  and  2  into the connection bolt arrangement as will be described in more detail below. In order to apply the actuating force, the stamping actuator  17  generally comprises a cylinder body with one or two movable pistons arranged therein, such that the one or two pistons are extendable and retractable relative to the cylinder body. If there is only one piston, this piston is movable relative to the cylinder body. On the other hand, if two pistons are provided, they are mutually opposed to each other and both extendable in opposite directions respectively from the cylinder body. In the illustrated embodiment, the cylinder body itself forms one stamping head  171 , while a second stamping head  172  is formed by the extendable piston. These stamping heads  171  and  172  form the actuator output members that respectively bear against and transmit forces into the mounting fixture blocks  7  and  12 . The mounting fixture blocks have respective configurations adapted to mate with or engage and prevent lateral displacement of the stamping heads  171 ,  172  of the actuator. 
     In the illustrated embodiment, the stamping actuator  17  is a hydraulic or pneumatic actuator, whereby a hydraulic fluid or a pneumatic gas under pressure is provided to a nipple or port  17 A through an appropriate pressure line in order to drive the stamping actuator  17  selectively as needed. As an alternative to such a hydraulic or pneumatic stamping actuator, and electrical actuator including an electric motor and a worm spindle or screw jack or any electrically powered force transmitter unit or the like could be used and positioned between the two mounting fixture blocks  7  and  12  as an alternative. In any event, the mounting fixture blocks  7  and  12  are appropriately configured respectively with a protruding mounting stub and a mounting hole, to engage correspondingly shaped features of the stamping heads  171  and  172  so that the stamping actuator  17  is reliably held in position once it is partially extended or actuated as shown in FIG.  2 . In any event, the stamping actuator  17  can selectively apply a pressing or extending force on the one hand, or a retracting or tension force on the other hand to correspondingly pivot the levers  1 ,  2  in a tool-closing direction or a tool-opening direction. 
     The above mentioned pulling extraction device  24  is preferably inserted into the bored hole B 1 . The pulling extraction device  24  generally comprises a nut head  241  provided with a hex head configuration or the like that can be engaged by any conventional bolt-tightening or loosening tool such as a torque wrench. The pulling extraction device  24  further comprises a cylindrical body  244  extending from the nut head  241  and having an external threading provided thereon. The nut head  241  is turned onto the external threading of the cylindrical body  244 . A further smaller-diameter cylindrical body  242  extends from an end of the larger-diameter cylindrical body  244  opposite the nut head  241 . The smaller-diameter cylindrical  242  is also provided with an external threading. The smaller-diameter cylindrical body  242  transitions into and terminates with a conical end body  243 . In the condition of the pulling extraction device  24  inserted into the bore B 1  as shown in FIG. 2, the smaller-diameter cylindrical body  242  extends through the first and second recesses  22  and  221 , and the conical end body  243  protrudes upwardly from the inner side surface  11  of the first lever  1  toward the pressing block  8  mounted on the second lever  2 . Once the tool is mounted and engaged on a connection bolt arrangement that is to be released, the threaded smaller-diameter cylindrical body  242  and the conical end body  243  will engage an end of the connection bolt as will be discussed in detail below. 
     The apparatus or tool according to the invention as shown in FIGS. 1 and 2 can be used for releasing a connection bolt arrangement that includes a connection bolt  18  and an expansion sleeve  23 , and that secures together two structural members  26  and  27 , such as structural plates or panel members  26  and  27  of an aircraft fuselage. In such a connection bolt arrangement, the connection bolt is typically conically tapered from a first end or larger diameter end to a second end or smaller diameter end. The inner bore or passage through the expansion sleeve  23  is similarly conically tapered from a first larger diameter end to a second smaller diameter end, while the outer diameter of the expansion sleeve  23  is substantially continuous and cylindrical. The bolt  18  is tightly pressed into the expansion sleeve  23 , whereby the conically tapered configuration causes a wedging effect, which in turn causes a radially outward expansion of the sleeve  23 , so that the expansion of the expansion sleeve  23  radially outwardly tightly secures the connection bolt arrangement to the structural members  26  and  27 , and thereby secures the structural members  26  and  27  to each other. Such an arrangement is shown in FIG.  2 . Thereby, the connection bolt  18  is force-locked or frictionally held in the expansion sleeve  23  in the secured condition. The bolt head or second narrower end of the bolt  18  protrudes upwardly from the corresponding end of the expansion sleeve  23  and protrudes outwardly from the structural member  26 , while the opposite larger-diameter end of the bolt  18  is received within the first end of the expansion sleeve  23  that protrudes from the structural member  27 . 
     In order to use the inventive tool for releasing such a connection bolt arrangement, the left free or second ends E 12  and E 22  of the levers  1  and  2  respectively equipped with the recesses  22  and  221  (representing a first pressing portion of the first lever) and the pressing block  8  (representing a second pressing portion of the second lever) are positioned in axial alignment with the connection bolt arrangement, while the levers  1  and  2  themselves reach around an end of the structural members  26  and  27 . Thus, the length of the levers  1  and  2  extending beyond the axis of the pivot joint arrangement  5  determines the “reach” of the tool to be able to release connection bolt arrangements displaced from the edge of the structural members  26  and  27 . 
     More particularly, the pressing block  8  preferably has a blind hole bored in a center thereof, which is adapted to receive the protruding bolt head or second narrower end of the connection bolt  18  thereon. The tool is positioned so that the bolt head of the bolt  18  is positioned and received and thereby fixed in an accurately positioned manner within this hole in the pressing block  8 . Meanwhile, the opposite protruding end of the expansion sleeve  23  is received in the first recess or depression  22 , such that the outer face of the protruding end of the expansion sleeve  23  rests on the first step or shoulder  22 A. Thus, the diameter of the first recess  22  and the second recess  221  respectively, is selected so that the protruding end of the expansion sleeve  23  is accurately positioned and laterally held in the first recess  22  while resting on the first shoulder  22 A. When the tool is operated as will be described below, the connection bolt  18  can be retracted out of the expansion sleeve  18  into the second recess  221  at least in the area between the first shoulder or step  22 A and the second shoulder or step  221 A. This relative arrangement of the end of the expansion sleeve  23  relative to the recesses of the first lever  1  is shown in detail in FIG.  2 A. 
     The arrangement of the pulling extraction device  24  in the bore B 1  and extending through the first recess  22  and the second recess  221  has been described above. It should be further understood that the connection bolt  18  has an internally threaded blind hole  18 A in the first larger-diameter end thereof as shown in FIGS. 2 and 2A. Thus, when the pulling extraction device  24  is inserted into the bore B 1  as described above, then the cylindrical body  244  is turned so that the small second cylindrical body  242  of the extraction device  24  is threaded into the threaded blind hole  18 A while the conical end body  243  comes to contact the bottom or end of the blind hole  18 A. Thereby, the extraction device  24  is engaged with the bolt  18 . By turning the nut head  241  of the extraction device  24 , the nut head is turned further onto the threaded cylindrical body  244  and a pulling force will be applied through the cylindrical body in the blind hole  18 A of the bolt  18 . 
     Further embodiments or features of the pulling extraction device  24  are also possible. For example, the shaft or cylindrical body  244  of the device  24  is smaller than the inner diameter of the bore B 1  so that it is freely movable therein, i.e. without being thread-engaged in the bore B 1 . The only threaded engagement is between the smaller cylindrical body  242  and the internal threading of the blind hole  18 A in the connection bolt  18 , and between the nut head  241  and the threaded cylindrical body  244 . Thereby, when the nut head  241  is turned with a wrench, the nut head  241  is threaded further onto the threaded body  244 , therety exerting a pulling force onto the bolt  18 . Most simply, the nut head  241  is embodied as a nut that can be threaded onto the threaded shaft or cylindrical body  244  of the bolt. In such an arrangement, the smaller cylindrical body  242  is first threaded into the blind hole  18 A to engage the bolt body  244  with the connection bolt  18 , and then the nut head  241  is threaded onto the protruding end of the bolt shaft or cylindrical body  244 , whereby a tightening or turning of the nut head  241  will exert a pulling force on the bolt shaft or cylindrical body  244  so as to exert a pulling force on the connection bolt  18 . 
     The specific operating steps for releasing a connection bolt arrangement using the tool will now be described. It will be understood that a preliminary or preparatory step a) involves assembling the individual parts or components of the tool kit into the complete tool as has been described above. Specifically, the forked bodies  4  and  6  are secured using the nuts  3  respectively to the levers  1  and  2 , the mounting fixture blocks  7  and  12  are secured to the levers  1  and  2  in the manner described above, the pressing block  8  is secured to the lever  2  as described above, the pivot pin or joint  13  is installed to secure the forked bodies  4  and  6  pivotally to each other, and the pulling extraction device  24  may be at least partly preinstalled in the bore B 1 . 
     In carrying out the preliminary assembly step a), it should be understood that different or variously configured mounting fixture blocks  7  and a pressing block  8  may be used and assembled with the levers  1  and  2  to meet the specific needs of a particular application at hand, e.g. depending on the particular stamping actuator  17  that is to be used, and the length, diameter and configuration of the connection bolt arrangement that is to be released. Moreover, an additional shim body or secondary mounting fixture block can be arranged between one of the mounting fixture blocks  7 ,  12  and the actuator  17 , for example on the mounting fixture block  7 , in order that the starting position of the left ends E 12  and E 22  of the levers  1  and  2  will be closer to each other in order to accommodate shorter bolt connection arrangements, so that a longer or longer-stroking stamping actuator  17  is not needed. Thus, the present apparatus can be easily adapted without significant cost or effort, to various different applications. Moreover, it should be understood that such modular or separable kit-construction is not a required limitation of the invention, but rather the invention also relates to a tool in which the effective pressing block is a unitary part of the second lever (e.g. similar to the recesses  22  and  221  being a unitary part of the first lever and serving a similar pressing function as the pressing block), the mounting fixture blocks are unitary parts of the two levers respectively, and the forked bodies are permanently connected to or unitarily incorporated in the levers. The various mountable blocks are optional, but make the inventive arrangement particularly versatile, adaptable, and portable. 
     In a subsequent step or measure b), the assembled tool or apparatus is positioned in such a manner on the connection bolt arrangement so that the pressing block  8  is positioned on the protruding bolt head or second end of the connection bolt  18 , while the protruding rim of the expansion sleeve  23  is received in the first recess  22  so as to rest against the first shoulder  22 A, as described above. 
     A next step c) involves arranging the stamping actuator  17  between the mounting fixture blocks  7  and  12 . In this state, the stamping heads  171  and  172  of the stamping actuator  17  are completely retracted or only partially extended. Thus, the actuator  17  can be positioned and inserted between the two mounting fixture blocks  7  and  12 , and the levers  1  and  2  can be pivoted to provide the largest jaw opening between the pressing block  8  and the first recess  22 . An additional shim block or secondary mounting fixture block may be arranged between the actuator  17  and one of the mounting fixture blocks  7  and  12 , if needed for the reasons discussed above. A slight manual pivoting of the levers  1  and  2 , or a slight extending actuation of the actuator  17  will bring the protruding cylindrical stub of the stamping head  172  into engagement with the corresponding cylindrical recess of the mounting fixture block  12 , while the protruding cylindrical stub of the mounting fixture block  7  engages the corresponding cylindrical recess provided in the stamping head  171 , as has been described above. Thereby, the actuator  17  is securely and properly positioned between the mounting fixture blocks  7  and  12 . 
     Next, a step d) is carried out, in which the pressing block  8  is adjusted on the protruding end or bolt head of the connection bolt  18 , and the protruding end or rim of the expansion sleeve  23  is adjusted in the first recess  22 , so that the respective components are precisely positioned and engaged with each other as has been described above. This prevents any possible lateral movement or shifting of the apparatus relative to the connection bolt arrangement, and of the components of the connection bolt arrangement relative to each other. Such an adjustment and a defined pre-securing of the tool relative to the bolt connection arrangement before carrying out the actual bolt releasing process is achieved as follows. 
     First, the apparatus is positioned relative to the bolt head and the protruding rim of the expansion sleeve as described above. Then, a hydraulic pump or other source of pressurized hydraulic fluid provides hydraulic fluid at a preliminary pressure to the stamping actuator  17 , which is embodied as a hydraulic actuator in this example. This preliminary pressure of the hydraulic medium is transmitted to the stamping heads  171  and  172  which thus extend or expand the actuator  17  into a partially extended condition so as to push against the mounting fixture blocks  7  and  12  to be secured relative thereto and to close the jaws of the levers  1  and  2  into a preliminary engagement with the connection bolt arrangement as described above. The arising compression or pressing forces FDS 1  and FDS 2  are transmitted through the mounting fixture blocks  7  and  12  through the levers  1  and  2 , thereby causing the levers to pivot about the pivot joint arrangement  5  so as to give rise, through a pivot-lever action, to corresponding or associated transmitted pressing forces FDS 1 ′ and FDS 2 ′ at the left ends E 22  and E 12  of the two levers  2  and  1  respectively. As a result, the pressing block  8  exerts the transmitted pressing force FDS 1 ′ axially against the protruding end of the connection bolt  8 , while the first shoulder  22 A of the recess  22  in the left end E 12  of the first lever  1  exerts a corresponding pressing force FDS 2 ′ against the protruding rim of the expansion sleeve  23  in an axial direction opposed to the transmitted pressing force FDS 1 ′. The forces applied as a result of the preliminary pressure applied by the hydraulic medium to the stamping actuator  17  are only sufficient to position and securely clamp the apparatus relative to the connection bolt arrangement, but are not sufficient to release the connection bolt  18  from the expansion sleeve  23 . 
     Thereafter, a step e) is carried out, in which the pulling extraction device  24  is fully inserted into the bore B 1  until the smaller cylinder body  242  reaches the blind hole  18 A in the first larger diameter end of the connection bolt  18  and is then threaded thereinto. By carrying out the above steps a) to e), the stage is set for achieving the actual release, or loosening and removal, of the connection bolt  18  from the expansion sleeve  23 . 
     Now the method proceeds with a further step f), wherein the hydraulic pressure provided to the stamping actuator  17  is increased, so as to correspondingly increase the applied actuator forces FDS 1  and FDS 2 , and correspondingly increase the transmitted pressing forces FDS 1 ′ and FDS 2 ′. In this context, the forces are preferably increased to about 20 tons, either as measured at the transmitted forces FDS 1 ′ and FDS 2 ′ or as measured at the actuator forces FDS 1  and FDS 2 , which may or may not be the same as the transmitted forces depending on the lever ratios used in a particular embodiment. Such a 20 ton force applied axially to the connection bolt  18  and the expansion sleeve  23  is generally still not sufficient to release the bolt from the sleeve. 
     Then, a further step g) is carried out, in which the pulling extraction device  24  is tightened by turning the nut head  241  further onto the threaded body  244 . This applies an additional pulling force or tension force FZ to the connection bolt  18  relative to the first lever  1  and thereby relative to the expansion sleeve  23  through the first shoulder  22 A. This tension force FZ is developed by turning the nut head  241  of the extraction device  24  with a wrench and particularly a torque wrench, for example in a clockwise direction. Thereby, as the pulling extraction device  24  is further tightened, the threaded smaller cylindrical body  242 , which was previously screwed into the blind threaded hole  18 A of the connection bolt  18 , thereby exerts an increasing tension force FZ, which succeeds in pulling the connection bolt  18  in a slow, controlled manner out of the expansion sleeve  23 . Thereby, the connection bolt  18  is retracted out of the connection sleeve  23  while the larger-diameter end of the connection bolt  18  moves progressively further into the second recess  221  until it comes to rest against the second shoulder  221 A. In this condition, the connection bolt  18  has been fully released from the expansion sleeve  23 , in a slow controlled manner, without any sudden jolt or shock, and the tool still remains reliably engaged with the connection bolt arrangement, because the compression or pushing force FDS 1  and FDS 2  applied by the stamping actuator  17  has further pivoted the levers  1  and  2  following the retraction movement of the connection bolt  18  relative to the expansion sleeve  23 . Generally, the tension force FZ required to release and extract the connection bolt  18  (in combination with the 20 ton pressing force) is about 11 tons. Thus, the total force acting on the connection bolt  18  relative to the expansion sleeve  23  to release the connection bolt arrangement is about 31 tons in the axial direction, but only about 11 tons of that force had to be developed by torquing the nut head  241  of the pulling extraction device  24  and converting the torque into an axial pulling force via the threading of the extraction device. 
     It is evident that the pivot joint arrangement  5 , i.e. the forked bodies  4  and  6  and the pivot joint or pin  13 , must support a reaction load that counters the applied actuator force FDS 1  and FDS 2 , and the transmitted pushing force FDS 1 ′ and FDS 2 ′. In view of the compressive force effective at the two opposite ends of each of the levers  1  and  2 , i.e. the forces FDS 1  and FDS 2  as well as the forces FDS 1 ′ and FDS 2 ′, it is understood that the forces applied to the pivot joint arrangement  5  arise as tension forces FZU 1  and FZU 2 . More specifically, while the forked bodies  4  and  6  are under tension along the axial extension direction of the protruding bolts thereof, and this tension is ultimately supported by the nuts  3  against the outer side surfaces  111  and  211  of the levers  1  and  2 , on the other hand the pivot pin  13  itself is subjected to shear loading. All the components of the pivot joint arrangement  5 , namely especially the forked bodies  4  and  6  including the protruding bolts thereof, the securing nuts  3 , and the pivot pin  13 , must be appropriately dimensioned and engineered to withstand the forces expected to arise in a given application. Based on a force balance, it is apparent that the pivot joint arrangement  5  must withstand a tension load of about 40 tons in the case in which the stamping actuator  17  applies an actuating force of about 20 tons. 
     By carrying out the above procedure in which the pressing forces FDS 1 ′ and FDS 2 ′ as well as the tension force or pulling force FZ are applied to the connection bolt  18  relative to the expansion sleeve  23 , the connection bolt  18  will generally be released and removed from the expansion sleeve  23 , i.e. the force-locked or frictional engagement therebetween will be loosened and the bolt  18  will be extracted out of the sleeve  23 . However, in the event that such a releasing of the connection bolt arrangement is not achieved by carrying out the above steps, the inventive method does not call for increasing the torque applied to the bolt head  241  of the pulling extraction device  24  in order to increase the applied pulling or tension force FZ above about 11 tons. Instead, the following series of steps is carried out. 
     According to a further step g), the hydraulic pressure applied to the stamping actuator  17  is reduced or removed so as to reduce the applied actuator force of 20 tons that had been generated in the preceding steps. Then the extraction device  24  is loosened or screw-turned back to its starting position. Thereby, the forces that had been applied to the connection bolt arrangement have been removed. 
     A further subsequent step h) provides that a hydraulic pressure is again applied to the stamping actuator  17  in order to develop a total pressing force of about 20 tons, which is transmitted through the levers  1  and  2 , and applied to the connection bolt arrangement as described above. Then the extraction device  24  is again tightened in order to apply a pre-tensioning of up to 11 tons onto the connection bolt  18  relative to the expansion sleeve  23 , whereby this tension force is increased to the desired maximum nominal value and then maintained at the nominal value so long until the connection bolt  18  is released from the expansion sleeve  23 . 
     In the event that the above repeated sequence of steps has still not successfully released the connection bolt  18  from the expansion sleeve  23 , then the above repetition of steps g) and h) is sequentially repeated as often as necessary until the desired release of the connection bolt arrangement is achieved. In any event, once the bolt  18  has been released from the expansion sleeve  23 , the pressure is removed from the actuator, the extraction device is screwed back to its initial position and the apparatus is removed from the working location, whereupon the released bolt connection components  18  and  23  can be removed from the structural components  26  and  27  manually or using simple hand tools. 
     While the example embodiment described herein uses a threaded bolt as the major tension developing component of the extraction device  24 , any other tension-developing extraction device could be used instead. The key feature of the extraction device  24  is that it engages the connection bolt  18  and applies a pulling force directly to the connection bolt  18  relative to the expansion sleeve  23 , which is braced against the lever on which the extraction device is mounted. The extraction device  24  may, for example, be a hydraulic or pneumatic piston device, an electric motor driven device, a ratchet device, or a lever connected to a pull rod. 
     Although the invention has been described with reference to specific example embodiments, it will be appreciated that it is intended to cover all modifications and equivalents within the scope of the appended claims. It should also be understood that the present disclosure includes all possible combinations of any individual features recited in any of the appended claims.