Patent Publication Number: US-2020282481-A1

Title: Hydraulically activated cutting tool

Description:
AREA OF TECHNOLOGY 
     The invention relates to a hydraulically activated cutting tool with two pivoting jaws that can pivot around a shared pivot axis, wherein a blade is formed on one pivoting jaw, and a stop on the other pivoting jaw. 
     The invention further relates to a method for separating a crimped connection, which connects two strand-shaped parts with each other, in particular two cables, preferably in the form of an H-tap crimped connection, with a cutting tool. 
     PRIOR ART 
     For example, a cutting tool of the kind in question is known from DE 20 2006 009 273 U1 (U.S. Pat. No. 8,671,579 B2). The pivoting jaws can be pivoted toward each other via the piston of a hydraulically activatable working tool, wherein the blade of the one pivoting jaw is moved in the direction toward the stop of the other pivoting jaw during this pivoting motion. An object arranged between the blade and stop, for example a rod-shaped object, further such as a cable or a bar, is cut by the blade as it abuts against the stop during this pivoting displacement. 
     SUMMARY OF THE INVENTION 
     With respect to the prior art described above, one object of the invention is regarded as improving a cutting tool of the kind in question in an advantageous manner and indicating an advantageous method for separating a crimped connection, in particular an H-tap crimped connection. 
     In a first inventive idea, one possible solution to the object involves a cutting tool in which the aim is for the blade to have a cutting edge that runs in the direction of the pivot axis, and to provide a gripping section that is formed on the pivoting jaw which has the stop and protrudes over a stop surface of the stop in the direction toward the opposing pivoting jaw. In a possible alternative embodiment, the gripping section can also be provided on the pivoting jaw which has the blade. 
     With respect to the method, it can be provided that the gripping section be designed to overlap sections of the strand-shaped parts that extend in the longitudinal direction of the strand-shaped parts before and/or after the connection, and that, given a gripping section that abuts against the strand-shaped part, the blade cuts through the crimped connection in such a way that the strand-shaped part can be removed. 
     In the following, reference to the crimped connection always also includes the H-tap crimped connection, but the embodiments also apply to a more general form of a given crimped connection in this regard. In addition, the focus is always placed on one or two cables with respect to the strand-shaped parts. However, the statements similarly apply more generally with reference to one or two strand-shaped parts. 
     The cutting tool is advantageously improved as a result of the indicated configuration. The cutting tool is now (also) suitable for cutting open crimped connections, for example, and further so-called H-tap crimped connections, for example, so as to again expose in particular one of the cables connected with each other by such a crimped connection, or remove the electrical connection to the other cable. 
     For this purpose, the cutting edge of the blade is aligned in a suitable manner in the direction of the pivot axis of the pivoting jaw. Accordingly, this makes it possible to align the cutting edge in essentially the direction of extension of a cable connected by the crimped connection. 
     The preferably provided gripping section makes it possible to overlap a cable, in particular the cable to be initially released from the crimped connection, preferably outside of the crimped connection, in particular to the side of the crimped connection. This overlap makes it possible to achieve a precise positioning of the crimped connection on the cutting tool, in particular on its stop. As is also preferred, this precise positioning can lead to a defined cutting process using the pivoting jaw blade; during this cutting process, the blade enters into the crimped connection transversely to the pivot axis along a circular line in relation to a plane, and separates or breaks it further along this circular line. 
     The user can hold the cutting tool close with a slight tug upon initiating the cutting process, so as to thereby ensure the desired cutting result. As also preferred in practice, this also makes it possible to expose the cable to be released and/or the H-tap crimped connection to a load, in particular a tensile load, using the gripping section, so as to thereby assume the desired cutting position in which the crimped connection is to be held in the cutting tool during the cutting process. 
     The blade can here further approximately and further preferably at least partially make tangential contact with the respective cable, or be passed by this cable tangentially at a small distance of up to 1 mm, for example, if necessary of up to 5 mm, for example. 
     Additional features of the invention are often explained below, to include the description to the figures, in their preferred allocation to the subject matter of claim  1  or to features of other claims. However, they can also be important as allocated to only individual features of claim  1  or the respective other claim, or each independently. 
     In a further development, the gripping section can form a front peripheral edge in the pivoting direction, which, as viewed in the direction of the pivot axis, is arranged to the side of the cutting edge. In this way, the gripping section can slide laterally by the blade during the cutting motion or the pivoting motion of the blade in the direction toward the stop. 
     In another possible configuration, the stop, in particular its stop surface, as well as the cutting edge can have identical or at least approximately identical extended lengths as viewed in the direction of the pivot axis. Given a gripping section arranged directly to the side of the stop, the cutting edge and gripping section can pivot by each other in almost a directly lateral manner during the cutting and pivoting displacement. In this way, the gripping section can form a lateral guide stop for the H-tap. 
     In addition, this effect can also come about by having two gripping sections each be arranged at one end of the stop surface as viewed in the direction of the pivot axis, as further preferred. In such an arrangement, the H-tap is preferably flanked by the gripping sections on both sides relative to the longitudinal extension of the cable, and drawn into the stop position via the cable overlapped by the gripping sections given a corresponding tensile load. 
     This can also cause the blade to cut uniformly into the material of the H-tap over the length of its cutting edge and separate it. 
     One or both gripping sections can be pivotably arranged, for example such that only one gripping section in an overlap position gets to the cable crimped in the H-tap. By contrast, the other gripping section can be pivoted into a position in which it is unsuitable for overlapping the cable. For example, such a pivoting displacement of a gripping section into a non-overlapping position can make sense in crimping connections or H-taps that have a larger degree of extension viewed in the direction of the pivot axis than would be permitted by the clear distance between two gripping sections or the length of the stop surface in the direction of the pivot axis. 
     Local conditions that do not permit any overlap might also cause one or even both gripping sections to be pivoted into a non-overlapping position. 
     It is possible to fixedly latch one or both gripping sections into at least one pivoting position, preferably at least into the position that does allow an overlap. The selected latched position must here be stable enough that it cannot be released by forces (in particular tensile forces) that act on the gripping section(s) during a conventional cutting process. The respective latched position can thus only be released intentionally. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       The invention will be described in more detail below based on the attached drawing, which only shows an exemplary embodiment. Shown on: 
         FIG. 1  is a perspective view of a hydraulically activated cutting tool; 
         FIG. 2  is a side view thereof; 
         FIG. 3  is a top view of the cutting tool; 
         FIG. 4  is the front view according to arrow IV on  FIG. 3 ; 
         FIG. 5  is the section along line V-V on  FIG. 4 , relating to an open position of the cutting jaws with the H-tap captured in the cutting mouth by the cutting tool; 
         FIG. 6  is the perspective view thereof; 
         FIG. 7  is the view according to arrow VII on  FIG. 6 ; 
         FIG. 8  is a view corresponding to  FIG. 5  relating to the closed position of the cutting jaws; 
         FIG. 9  is the perspective view thereof; 
         FIG. 10  is a schematic view of the cutting line through an H-tap; 
         FIG. 11  is a perspective view according to  FIG. 6 , but relating to a situation with a disengaged gripping section; 
         FIG. 12  is an exploded perspective view of the pivoting jaws with two gripping sections. 
     
    
    
     DESCRIPTION OF THE EMBODIMENTS 
     Initially shown and described in relation to the illustration on  FIG. 1  is a hydraulically activatable, in particular electro-hydraulically activatable, cutting tool  1  in a rod-like configuration. 
     The cutting tool  1  initially and essentially has a drive unit part  2 , which can simultaneously comprise a gripping area  3 . Such a drive unit part  2  is known from WO 2003/084 719 A2 (U.S. Pat. No. 7,254,982 B2), for example. The content of this WO publication or US publication is hereby included in the disclosure of the present invention in its entirety, including for the purpose of also incorporating features of this WO publication or US publication into the claims of the present invention. 
     A working head  4  adjoins the drive unit part  2  toward a free end of the working device. It can be replaceably mounted on the drive unit part  2 , preferably by a separation in the area of a hydraulic cylinder. As also preferred, the working head  4  can further be mounted in a freely rotatable manner around a working head longitudinal axis x relative to the drive unit part  2  or the respective receptacle for the working head  4 . 
     An accumulator  5  is set up to supply electrical power in particular to an electric motor that drives the hydraulic fluid pump, but additionally to a control unit (not shown) and other electrical components in the cutting tool  1 . 
     The gripping area  3  can be designed for conventionally grasping the cutting tool  1  with a hand. An ergonomically beneficial activating key  6  allocated to the gripping area  3  is provided. 
     Two pivoting jaws  7  and  8  that can be pivoted toward and away from each other are provided in the working head  4 . The latter can be pivoted around a shared geometric pivot axis y, wherein this pivot axis y is transvers to the working head longitudinal axis x. 
     The two pivoting jaws  7  and  8  comprise a blade  10  or a stop  11  on one side of a bearing eye  9 , and a respective acting surface  13  in the form of a curved path on a jaw leg  12  on the other side of the bearing eye  9 . 
     The acting surfaces  13  of both pivoting jaws  7  and  8  are arranged facing each other. 
     The bearing eyes  9  of both pivoting jaws  7  and  8  are aligned coaxially to each other, and in the assembled state are penetrated by a bolt  14 , for example a locking bolt. This bolt  14  is mounted in location holes of a drive head-side receiving neck  15  on either side of the pivoting jaws  7  and  8 . 
     The receiving neck  15  has a conventional fork-shaped design, and has a bolt receptacle that extends transverse to the longitudinal extension of the receiving neck  15  and penetrates the fork leg, preferably in the form of a through bore in which the bolt  14  is mounted. 
     The acting surfaces  13  of the pivoting jaws  7  and  8  protrude into the area between the fork legs of the receiving neck  15 , and are exposed to rollers  16  of the drive unit part that can be preferably hydraulically displaced in the direction toward the acting surfaces  13  during a pressing process, which causes the pivoting jaws  7  and  8  to spread in the area of the curved path or acting surfaces  13 , and thus the blade  10  and stop  11  of the pivoting jaws  7  and  8  to be pivotably displaced in a direction toward each other. 
     A hydraulic piston can be provided in the working head  4  so as to pivotably displace the pivoting jaws  7  and  8  in a cutting direction. The latter can be displaced along the axis x in a hydraulic cylinder against the force of a restoring spring. The continuous surface of each roller  16  forms an interacting surface, via which the piston can indirectly act on the acting surfaces  13 . 
     When the activating key  6  is correspondingly activated during operation of the cutting tool  1 , for example by way of a pumping plunger, hydraulic fluid is pumped into the hydraulic cylinder via a hydraulic line, so as to correspondingly act on the front piston surface facing the hydraulic fluid. 
     The hydraulic piston displaced opposite the force of the restoring spring through exposure to a hydraulic fluid can move a carrier for the roller  16  being exposed to a piston rod  17  linearly along the longitudinal axis x, wherein the pivoting jaws  7  and  8  are displaced toward each other in the direction of a closed position as the displacement path of the rollers  16  increases proceeding from a base position according to  FIG. 5  as the result of a force-transmitting interaction between rollers  16  and the curved path-like acting surfaces  13 . 
     The blade  10  of the one pivoting jaw  7  has a cutting edge  18 . The latter runs in the direction of the pivot axis y, correspondingly preferably parallel to the latter. 
     The cutting edge  18  can be formed at the outer end of the pivoting jaw  7 , and inwardly, i.e., in the direction to the pivot axis y, captured from behind by a recess  19  that has a pocketlike longitudinal section according to  FIG. 5  and opens in the direction toward the cutting mouth M. 
     This type of pocket-like recess  19  can also have the pivoting jaw  8  having the stop  11 . The recesses  19  of both pivoting jaws  7  and  8  face each other with their openings, and can essentially thereby border the cutting mouth M. 
     The stop  11  can essentially be formed by a stop surface  20 , which can be preferably centrally exposed to the cutting edge  18  in a closed position of the pivoting jaws, further in a longitudinal sectional view according to  FIG. 8 . At the very least, the cutting edge  18  is directed toward the stop surface  20  in the closed position of the pivoting jaws. 
     The blade  10  or its cutting edge  18  correspondingly moves around the pivot axis y along a geometric circular line L, wherein this circular line L penetrates the stop surface  20  beyond a possible stop position (see  FIG. 10 ). 
     The stop surface  20  or the stop  11  and the blade  10  or its cutting edge  18  can have at least approximately the same extension lengths as viewed in the direction of the pivot axis y (see  FIG. 4 ). 
     As is also preferred, this cutting edge length or stop length can correspond to a corresponding degree of extension of an H-tap  21  to be separated using the cutting tool  1 . 
     Such an H-tap  21  is used for crimping together in particular two cables  22  and  23 . Such a crimped connection can preferably only be undone by destroying the H-tap  21 . The cutting tool  1  is preferably used for this purpose. 
     The width of an H-tap  21  in the direction of extension of the cables  22  and  23  running essentially parallel to each other can correspond to the prescribed degree of extension of the cutting edge  18  or the stop  11 . 
     With respect to a front view according to  FIG. 4 , a gripping section  24  can be arranged to the side of the stop  11 . In the exemplary embodiment shown, gripping sections  24  and  25  are provided on either side of the stop, and each have peripheral edges  31  on their free ends. 
     The gripping section  24 ,  25  can be pivotably mounted to the pivoting jaw  8  to the side of the stop  11 . As is also preferred, the respective pivot axis z can run aligned with the pivot axis y, wherein the pivot axis z of the one gripping section  24  can further concurrently form the geometric pivot axis of the additional gripping section  25  in an axial elongation. 
     Each gripping section  24  and  25  preferably has two pivoting positions that can be fixedly latched. These two pivoting positions can be offset relative to each other by 180 degrees in relation to the pivot axis z. 
     To this end, each gripping section  24 ,  25 , as schematically denoted on  FIG. 12 , can have a latching pin  26 , which can be introduced into a corresponding latching recess  27  or  28  so as to fixedly latch the gripping section  24 ,  25 . 
     For unlatching purposes, the gripping section  24  or  25  can be displaced along its pivot axis z against the restoring force of a spring  29  along the retaining pin  30  that forms the axial body, and then can be pivoted into the other pivoting position if needed, after which the latched position can be secured in this position by introducing the latching pin  26  into the other latching recess. 
     One of the gripping sections  24 ,  25  or even both gripping sections  24 ,  25  can thus be moved into a pivoting position, in which the latching pin  26  rests in the latching recess  28 , and the respective gripping section protrudes over the stop surface  20  of the stop  11  with its peripheral edge  31  in the direction toward the opposing pivoting jaw  7  or the opposing blade  10 . The gripping section  24  or  25  protrudes over the stop surface  20  like a fang, wherein, in an open position of the pivoting jaw as shown on  FIG. 5  with reference to a projection in a plane transverse to the longitudinal axis y, the free end with the peripheral edge  31  of each gripping section  24 ,  25  can be spaced a distance apart from the facing cutting edge  18  viewed in the pivoting direction. This distance can correspond to a thickness of the latter viewed perpendicular to the widthwise extension of the H-tap  21 , or exceed this thickness. 
     In process of cutting open an H-tap  21 , both gripping sections  24  and  25  fixedly latched in the overlap position overlap the protruding cable sections of the cable  22  to be removed from the H-tap  21  to the side of the H-tap  21  (see  FIG. 6 ). As a result, the H-tap  21  is initially guided on either side. In addition, pulling by means of the cutting tool  1  in a pulling direction r roughly along the longitudinal axis x, causes the H-tap with the overlapped cable  22  to be drawn into the interstice that arises between the gripping sections  24  and  25  and the stop surface  20 , so that this results in a defined stop position of the H-tap  21 . 
     The cable  22  to be removed from the H-tap  21  correspondingly extends inside of the cutting mouth M. 
     As evident from the schematic view on  FIG. 10 , the H-tap  21  that was brought into the correct cutting position in particular by pulling is penetrated essentially along the circular line L by the cutting edge  18  of the blade  10 , thereby exposing in particular the cable  22  to be removed, wherein an approximate tangential section that at least partially arises can come about with reference to the cable cross section according to  FIG. 10 . The cutting edge  18  is preferably guided by the outer cable surface along the circular line L, if necessary while peeling the tap material from the cable  22 . A separation of the H-tap  21  is essentially achieved in the area between the cables  22  and  23 . 
     As evident from the view on  FIG. 11 , a gripping section  24  or  25  can be pivoted back out of the overlap position and there be fixedly latched. For example, this can happen in H-taps  21  whose width as viewed in the direction of extension of the cutting edge  18  is greater than the cutting edge length or the length of the stop surface  20 , which can essentially correspond to the inner clearance of the gripping sections  24  and  25  in the direction of extension of the pivot axis z. 
     In such an arrangement, the gripping section  24  or  25  might thus only overlap the cable  22  on one side, and this single gripping section might produce the tensile load on the H-tap  21  for bringing the latter into the proper cutting position. 
     The above statements serve to describe the inventions encompassed by the application as a whole, which even independently further develop the prior art at least with the following material combinations, wherein two, several or all of these feature combinations can also be combined, specifically: 
     A hydraulically activated cutting tool  1 , characterized in that the blade  10  has a cutting edge  18  that runs in the direction of the pivot axis y, and that a gripping section  24 ,  25  is provided that is formed on the pivoting jaw  8  having the stop  11  and protrudes over a stop surface  20  of the stop  11  in the direction toward the opposing pivoting jaw  7 . 
     A cutting tool, characterized in that the gripping section  24 ,  25  forms a front peripheral edge  31  in the pivoting direction, which, as viewed in the direction of the pivot axis y, is arranged to the side of the cutting edge  18 . 
     A cutting tool, characterized in that two gripping sections  24 ,  25  are formed, which are each arranged at one end of the stop surface  20  as viewed in the direction of the pivot axis y. 
     A cutting tool, characterized in that one or both gripping sections  24 ,  25  are pivotably arranged. 
     A cutting tool, characterized in that one or both gripping sections  24 ,  25  can be fixedly latched in at least one pivoting position. 
     A method for separating an H-tap crimped connection of two cables  22 ,  23  with a cutting tool ( 1 ) according to one of claims  1  to  5 , wherein the gripping section  24 ,  25  is designed to overlap a cable section that extends in the longitudinal direction of the cable  22  before and/or after the H-tap  21 , and that, given a gripping section  24 ,  25  abutting against the cable section, the blade  10  cuts through the H-tap  21  in such a way that the cable  22  can be removed. 
     A cutting tool or a method, characterized by one or several of the characterizing features of one of the preceding claims. 
     All disclosed features (whether taken separately or in combination with each other) are essential to the invention. The disclosure of the application hereby also incorporates the disclosure content of the accompanying/attached priority documents (copy of prior application) in its entirety, also for the purpose of including features of these documents in the claims of the present application. Even without the features of a referenced claim, the subclaims with their features describe independent inventive further developments of prior art, in particular for generating partial applications based on these claims. The invention indicated in each claim can additionally have one or several of the features in the above specification, in particular those provided with reference numbers and/or indicated in the reference list. The invention also relates to embodiments in which individual features mentioned in the above specification have not been realized, in particular to the extent that they are obviously unnecessary for the respective intended use, or can be replaced by other technically equivalent means. 
     
       
         
           
               
             
               
                   
               
               
                 Reference List 
               
               
                   
               
             
            
               
                   
               
            
           
           
               
               
            
               
                 1 
                 Cutting tool 
               
               
                 2 
                 Drive unit part 
               
               
                 3 
                 Gripping area 
               
               
                 4 
                 Working head 
               
               
                 5 
                 Accumulator 
               
               
                 6 
                 Activating key 
               
               
                 7 
                 Pivoting jaw 
               
               
                 8 
                 Pivoting jaw 
               
               
                 9 
                 Bearing eye 
               
               
                 10 
                 Blade 
               
               
                 11 
                 Stop 
               
               
                 12 
                 Jaw leg 
               
               
                 13 
                 Acting surface 
               
               
                 14 
                 Bolt 
               
               
                 15 
                 Receiving neck 
               
               
                 16 
                 Roller 
               
               
                 17 
                 Piston rod 
               
               
                 18 
                 Cutting edge 
               
               
                 19 
                 Recess 
               
               
                 20 
                 Stop surface 
               
               
                 21 
                 H-tap 
               
               
                 22 
                 Cable 
               
               
                 23 
                 Cable 
               
               
                 24 
                 Gripping section 
               
               
                 25 
                 Gripping section 
               
               
                 26 
                 Latching pin 
               
               
                 27 
                 Latching recess 
               
               
                 28 
                 Latching recess 
               
               
                 29 
                 Spring 
               
               
                 30 
                 Retaining pin 
               
               
                 31 
                 Peripheral edge 
               
               
                 r 
                 Pulling direction 
               
               
                 x 
                 Longitudinal axis 
               
               
                 y 
                 Pivot axis 
               
               
                 z 
                 Pivot axis 
               
               
                 L 
                 Circular line 
               
               
                 M 
                 Cutting mouth