Patent Publication Number: US-11660098-B2

Title: Hand-held grasping device

Description:
CROSS-REFERENCES TO RELATED APPLICATIONS 
     This application is a Continuation of U.S. application Ser. No. 15/503,147, filed Feb. 10, 2017, which is a § 371 and claims priority of PCT/US2015/46048 filed Aug. 20, 2015, and claims priority to the following U.S. patent applications: (1) U.S. Provisional Patent Application No. 62/039,836, entitled “Parallel Sustained Pressure Hinge/Parallel Jaw Apposition Clamp” and filed Aug. 20, 2014; and (2) U.S. Provisional Patent Application No. 62/067,782, entitled “Hand tool” and filed Oct. 23, 2014. The entire contents of the aforementioned patent applications are incorporated herein by their entirety. 
    
    
     BACKGROUND 
     The present disclosure relates to a hand-held tool for gripping and/or compressing an object. 
     Various designs of plyers-type hand-tools have been proposed for specific applications. Generally these tools have two pivotally attached arms with the arms acting as levers to increase the gripping or compression force applied by jaws at the front end of the arms. In the medical and surgical field, hemostats and surgical clamps are examples of these types of tools. 
     One specific, non-limiting example in the surgical field is removal of part of the liver (hepatic resection), which is often performed to remove a tumor. Blood loss is a serious complication associated with this procedure. Multiple surgical techniques and devices have been developed to minimize blood loss and improve outcomes in hepatic resection. The so-called clamp-crush technique is a preferred technique. 
     The clamp-crush technique generally involves crushing the liver parenchyma using a hemostatic clamp tool to expose small vessels and biliary radicals, which are then divided and sealed via radio frequency (RF) energy provided to the jaws of the tool. Various tools have been proposed for this purpose. However, challenges remain in providing a coaptive surgical sealing tool offering superior performance and efficiency in a simple and low-cost design. 
     SUMMARY 
     A hand tool has a pivot connection pivotally attaching a first arm to a second arm, with the pivot connection fixed relative to the first arm and movable to first and second positions relative to the second arm. A jaw spring urges the pivot connection into the first position. When jaws on the front ends of the arms clamp with force greater than a pre-set threshold, the spring force of the jaw spring is overcome and the jaws may move linearly apart, allowing for more uniform clamping. An arm spring in the first arm may limit the clamping force that may be applied to the clamped object. 
     In one aspect, there is disclosed A hand-held tool comprising: a first arm having a first jaw section and a first handle section; a second arm having a second jaw section and a second handle section; a pivot connection pivotally attaching the first arm to the second arm, wherein the pivot connection is fixed relative to the first arm and movable between first and second positions relative to the second arm; and a jaw spring urging the pivot connection into the first position. 
     In another aspect, there is disclosed A hand tool comprising; a first arm having a front section pivotally attached to a rear section via an arm hinge pin; an arm spring extending between the front section and to the rear section of the first arm; a jaw hinge pin pivotally connecting the front section of the first arm to a second arm, with the hinge pin at a fixed position on the first arm, and the hinge pin movable into first and second positions relative to the second arm; and a jaw spring urging the hinge pin towards the first position, and wherein the hinge pin is movable against the bias of the spring into the second position, wherein the front sections of the first and second arms may be spaced apart and substantially parallel to each other. 
     In another aspect, there is disclosed a hand tool comprising; a first arm having a front section pivotally attached to a rear section via an arm hinge pin; an arm spring extending between the front section and to the rear section of the first arm; a jaw hinge pin pivotally connecting the front section of the first arm to a second arm, wherein the hinge pin is at a fixed position on the first arm, and the hinge pin is movable into first and second positions relative to the second arm; a jaw spring urging the hinge pin towards the first position, and with the hinge pin movable against the bias of the spring into the second position wherein front sections of the first and second arms may be spaced apart and substantially parallel to each other; a first electrode on the front section of the first arm, and a second electrode on a front section of the second arm; wire leads on at least one of the first and second arms connecting to the first and second electrodes; and an irrigation line in or on at least one of the first and second arms connecting to front section of the first or second arms, and an aspiration line in or on at least one of the first and second arms connecting to the front section of the first or second arms. 
     Other features and advantages should be apparent from the following description of various embodiments, which illustrate, by way of example, the principles of the disclosure. 
    
    
     
       BRIEF DESCRIPTION OF THE DRAWINGS 
       In the drawings, the same element number indicates the same element in each of the views. 
         FIG.  1    is a front, top and side perspective view of a hand tool. 
         FIG.  2    is a side view of the tool shown in  FIG.  1   . 
         FIG.  3    is an enlarged detail view of the tool of  FIG.  1   . 
         FIG.  4    is a front, top and side perspective view of a second embodiment of a hand tool. 
         FIG.  5    is an enlarged section view detail of the tool of  FIG.  4   . 
         FIG.  6    is an exploded perspective view of the tool of  FIG.  4   . 
         FIG.  7    is an enlarged perspective view of the jaws of the tool of  FIG.  4    in an open angle position. 
         FIG.  8    is a side view of the tool of  FIG.  4    in the closed position. 
         FIG.  9    is a side view of the tool of  FIG.  4    in the open parallel position. 
         FIG.  10    is a front, top and side perspective view of another embodiment of a hand tool. 
         FIG.  11    is a side view of the tool shown in  FIG.  10   . 
         FIG.  12    is an enlarged top, front and side perspective view of the first arm of the tool shown in  FIGS.  11  and  12   . 
         FIG.  13    is a front, top and side perspective view of another embodiment of a hand tool. 
         FIG.  14    shows another embodiment of a hand tool. 
         FIG.  15    shows a perspective, enlarged portion an arm of the tool. 
         FIG.  16    shows a side view of the arm of  FIG.  15   . 
         FIG.  17    shows another embodiment of a hand tool. 
     
    
    
     DETAILED DESCRIPTION 
     Disclosed is a hand tool for uses such as, for example, general manufacturing, assembly, and repair where grasping, clamping and/or holding is needed. The tool is sometimes described herein in the context of being a coaptive surgical sealing tool although it should be appreciated that this is just an example and that the tool is configured for use in a variety of situations. 
     As shown in  FIGS.  1 - 3   , a first embodiment of a hand tool  20  has a first arm  22  pivotally attached to a second arm  52  at a hinge joint  44 . The front section (forward of the hinge joint  44 ) of the first arm  22  has a first jaw  24  and the front section of the second arm  52  similarly has a second jaw  54 . A grabbing element, such as a finger ring  26 , is provided at the back end of the back section  28  of each of the arms  22  and  52 . The second arm  52  includes an arm slot or opening  56 , with a reduced width hinge section  30  of the first arm  22  positioned within the slot  56 . Referring to  FIG.  2   , where the tool  20  is configured as a surgical tool, wire leads  60  and  62  may optionally be provided on or in one or both arms  22  and  52  to electrodes  66  and  64  on the arms  22  and  52 . The wire leads  60  and  62  may terminate at a connector on one or both of the arms, to allow energy such as RF (radio frequency) or microwave energy, to be supplied to the electrodes. In an embodiment the energy is at a frequency of at least 100 kHz. In another embodiment, microwave frequency is greater than 300 mHz. 
     As shown in  FIG.  1   , for applications such as surgery of the liver, the jaws  24  and  54  may be made long and slender, for example with a length from the hinge joint  44  to the front tip  46  of each jaw ranging from about 20 to 80 mm, or 30-40 mm, and with jaws having a maximum width and maximum height of about 1.5 to 5 mm. The jaws may taper outwardly in height and width from the front tip to the hinge joint  44 , with the width and height of each jaw  1  to 2.5 times greater at the hinge joint  44  than at the front tip  46 . The jaws  24  and  54  may also curve to one side, such as the left side in the example shown in  FIG.  1   . It should be appreciated that the aforementioned dimensions are just examples and that variations are within the scope of this disclosure. 
     Turning to  FIG.  3   , a spring arm  40  of a spring  34  may be attached to the first arm  22 . The spring  34  may have spaced apart upright clevis plates  36  on opposite sides of the second arm  52 , with a hinge pin  42  extending through the plates  36  and the second arm  52  to form the hinge joint  44 . The hinge pin  42  is movable via flexing of the spring  34 , from an up or open position shown in  FIG.  3   , to a down or closed position shown in  FIG.  2   . In the up position the hinge pin  42  is raised up and largely out of a recess  32  in the first arm  22  as shown in  FIG.  3   . In the down position the hinge pin  42  is largely within the recess  32  as shown in  FIG.  2   . As shown in  FIG.  2   , in the down position, the plane or axis of each jaw may be centrally aligned with the hinge pin  42 , with the jaws parallel to and in contact with each other. The hinge pin  42  defines an axis of rotation of the first arm  22  and the second arm  52  relative to one another wherein the axis of rotation can change position based on the position of the spring arm  40 . 
     Referring to  FIG.  2   , in use the jaws  24  and  54  are opened, moved to engage an object, such as a work piece, or tissue, and then closed. With nominal clamping pressure applied, in a surgical application the jaws may act as conventional hemostat or clamping jaws, as shown in  FIG.  2   . However, if greater clamping pressure is applied, the force acting to separate the jaws exceeds the force of the spring acting to hold the hinge pin  42  in the down position. As this occurs, the hinge pin  42  moves up (or away from the first arm  22 ) towards the up position shown in  FIG.  3   . Correspondingly, the jaws move linearly away from each other rather than to the teen relative to one another. As a result, the jaws are able to clamp the work piece, or tissue, with more uniform clamping force. The linear separating movement of the jaws may be limited by a finger  38  on the first arm providing a hard stop position against the spring  34 . The linear separating movement of the jaws depends on the reaction force on the jaws (acting to separate the jaws). Depending on the geometry of the clamped object or tissue, the linear separating movement may be independent of the pivoting movement or angular position of the jaws. 
     With the jaws closing at an acute angle as shown in  FIG.  2   , the clamping force is greater closer to the hinge joint  44  and less at the tip  46 , so that the clamping force may vary significantly. With the tool  20 , however, after a pre-set clamping force is exceeded, the jaws move apart linearly, helping to provide a more uniform clamping force. As shown in  FIG.  3   , the jaws may remain substantially parallel as they move linearly apart. The pre-set clamping force is selected via the spring constant of the spring. Different embodiments of the tool  20  may have springs with different spring constants selected for use in different hand tool uses, or different surgical procedures. For a non-limiting example, the spring constant may be in the range of 2-8 Newtons/meter or 36 Newtons/meter. 
     In the configuration shown in  FIGS.  1 - 3   , the hinge pin  42  moves in an arc having a radius equal to the length of the spring arm  40 . Consequently, as the jaws move linearly relative each other, there is also a small front/back movement as well. Hence, with the jaws fully linearly open, and the hinge pin  42  in the full up position, the second jaw is positioned slightly behind the first jaw  22 , as shown in  FIG.  3   . Clearance to allow for this slight longitudinal shifting between the jaws may be provided via the leg slot  56 . The hinge pin  42  vertical range of travel may be about 2-10 or 3-7 mm. 
     Turning to  FIGS.  4 - 6   , in a second embodiment  80 , a first arm  82  is pivotally attached to a second arm  84  via a hinge pin  86 . Latch plates  92  may be used to latch the arms. As shown in  FIG.  5   , as applied to a surgical hand tool, electrical leads  60  and  62  along with an irrigation line or drip  120  and an aspiration or suction line or tube  122  may extend on or in either arm to electrodes  96  and  100  on first and second arms  94  and  98 . The tubes or lines  120  and/or  122  may be routed in a joggle around the hinge pin  86 . As shown in  FIG.  6   , the first arm  82  may be provided with separate front and back sections  114  and  116 , such as to allow for easier manufacture. The first arm  82  may be positioned within an arm slot  90  of the second arm  84 . Also as shown in  FIG.  6   , an insulator plate or layer  130  may be positioned between the arms  94  and  98  and the electrodes  96  and  100 . Irrigation and aspiration lines may also be provided on the tool  20 . 
     As shown in  FIG.  7   , the electrodes  96  and  100  may have angled complimentary surfaces  102  and  104  joining together at an edge  106  adjacent to the tip  46 . Aspiration and irrigation openings  124  and  126  connecting with the aspiration and irrigation lines may be provided in the electrodes  96  and  100 . As shown in dotted lines in  FIG.  7   , the aspiration openings  124 , if used, may also be located on a top and/or side surface of one or both jaws, in addition to, or instead of, locating the aspiration openings in the electrodes. The electrodes  96  and  100  may have complimentary shapes, so that the jaws mate uniformly when closed, with little or no space between them. The inner surfaces of one or more of the arms may be textured or can have any surface characteristic, such as serrations, that improves the gripping ability of the arms relative to tissue or other material. The serrations, if present, may also be shaped to bias any irrigation to flow toward a predetermined location of the arms, such as toward a front region.fparalle 
     In another embodiment, one or both arms may have a portion that is flexible or movable relative to another portion of the arm. For example, a tip region of one or both of the arms may pivot or rotate relative to a second region of the arm. The rotatable or pivotable portion may be spring-loaded toward a default position. 
     Turning to  FIGS.  8  and  9   , the hinge pin  86  on the second arm  84  may extend into a pin slot  88  in the first arm  82 . A jaw spring  110  may be attached to the first arm  82  with set screws  112 . The jaw spring  110  exerts upward force on the hinge pin  86 , holding the jaws together, as shown in  FIG.  8   . 
     Referring to  FIG.  9   , as with the tool  20 , when the jaws clamp onto an object with a force exceeding a pre-set amount, the force of the jaw spring  110  is overcome. The hinge pin  86  moves from the up position shown in  FIG.  8   , to the down position shown in  FIG.  9   , where the jaws are spaced apart and may be largely parallel to each other. The jaw spring  110  may be a spring wire. Other forms of springs such as coil compression springs, leaf springs and non-metal spring elements, such as resilient foam, rubber and plastic elements, may also be used. 
     As described, the pivot pin  42  or  86  provides a pivot point where the arms intersect, with the pivot point moving along a linear or curvilinear pathway up or down to accommodate the thickness of the clamped object. The spring moves the pivot pin. If the spring constant is too high, the pivot point will not move enough to keep the jaws parallel. Similarly, if the spring constant is too low, the spring will allow the pivot pin to move too easily, with the pivot pin moving too far to keep the jaws parallel. The spring constant may be selected based on the characteristics of the object to be clamped, or in surgical applications, the stiffness of the tissue to be operated on. 
     Relative to surgical uses, testing on calf liver revealed that 5 N of force was sufficient to fully collapse the calf liver, suggesting that a spring force on the order of 5 N may be suitable in some embodiments of the tool  20 . As shown in  FIGS.  8  and  9   , securing the jaw spring  110  in place with fasteners  112  allows the spring to be quickly and easily replaced. This allows the tool  80  to be adapted for different uses. 
     In addition to providing more even and uniform clamping force along the long jaws, the capability of providing parallel jaws, in surgical applications, also promotes an even seal along the long jaws. Substantially parallel jaws also tends to obviate any need for segmented RF tips on the jaws to allow different power or time settings along the jaw&#39;s length, and the associated added RF generator complexity and lead wires. In an embodiment, the jaws initially pivot or rotate relative to one another when initially opened and then transfer to parallel position and translate relative to one another without any pivoting after the arms have initially achieved a certain level of movement relative to one another. 
     Turning to  FIGS.  10 - 12   , a third hand tool  150  may be the same as the second tool configuration  80  shown in  FIGS.  4 - 9   , with the following changes. A first arm  152  is divided into a front segment  154  pivotally attached to a rear segment  156  via an arm hinge pin  158 . As shown in  FIGS.  11  and  12   , an arm spring  160  extends between the front segment  154  and the rear segment  156 . The arm spring  160  may be provided in the form of a spring wire, or as another type of spring similar to the alternative spring options discussed above for the jaw spring  110 . The arm spring  160  may be positioned within a spring slot  162  in the top surface of the front and rear segments. 
     As shown in  FIG.  11   , the central section of the arm spring  160  may be supported on a curved arch surface  166  extending over the hinge pin  158 , to reduce bending stresses on the arm spring  160 . The ends of the arm spring  160  may be positively attached to the front and rear segments via set screws, bonding, welding, etc. Alternatively, as shown in  FIGS.  11  and  12   , the arm spring  160  may be held in place via spring force, with the front end of the arm spring  160  captured under a bridge section  164  on the front segment, as shown in  FIG.  12   , and with the back end of the arm spring  160  captive within a slot in the rear segment  156 , as shown in  FIG.  11   . Capturing the arm spring  160 , rather than positively attaching the arm spring  160  to the segments allows the arm spring  160  to move slightly relative to the arm segments when the rear segment pivots relative to the front segment, which may simplify the hinge design. 
     An embodiment of arm spring  160  resists any deflection until the desired compression force limit is reached, so that the tool  150  would have a familiar feel and operation in the surgeon&#39;s hand. Such man arm spring  160  also then freely allows deflection when the desired compression force is exceeded, to as to precisely limit the compression force. Alternative spring configurations may be used to simulate such a spring. For example, laterally curved leaf springs, collapsing hollow tube springs, and similar alternatives may be used in place of a solid round wire to better achieve preferred handling characteristics of the tool  150 . 
     The arm spring  160  is pre-loaded or tensioned so that it exerts torque acting counterclockwise about the arm hinge pin  158  in  FIG.  11   . Consequently, the arm spring  160  holds the rear segment  156  in a straight or locked out position as shown in  FIGS.  11  and  12   . In ordinary use with nominal clamping force applied, the tool  150  operates in the same way as the tool  80  shown in  FIGS.  4 - 6   . However, if excessive force is applied, the arm spring  160  will bend, allowing the rear segment  156  of the first arm  152  to pivot about the arm hinge pin  158  downward towards the second arm  180 . Consequently, the clamping force applied by the jaws is automatically limited. As a result, inadvertent crushing of the clamped object is avoided. Damage to the long slender jaws caused by inadvertently clamping down on a hard object is also avoided. The arm spring  160  may be selected to have a spring constant which limits the clamping force to a desired maximum, for example 3-5 Newtons. 
     Referring back to  FIGS.  10  and  11    the rear arm segment  154  may have an upward curve, or an upward angle AA of 10-35 degrees, to provide clearance for pivoting movement of the rear arm segment when the compression force limit is exceeded. The second arm  180  may also curve away or extend at angle away from the first arm  150  for the same purpose. The pivoting design of the first arm  152  may optionally be used on the second arm  180 , or on both arms. 
     Also as shown in  FIGS.  10  and  11   , the arm hinge pin  158  may generally be located at a midpoint between the handle loop  26  and the jaw hinge pin  86 . Of course, the specific position of the arm hinge pin  158  may be shifted to the front or back of the first arm, depending on the tool application. 
       FIG.  13    shows a fourth tool embodiment  190  having a first arm  192  and a second arm  194  which may be a mirror image of the first arm  192 . The arms  192  and  194  are connected by an X-linkage  196 . The front ends of the X-linkage may be pivotally pinned to the arms via front pins  204 , and the back ends of the X-linkage having slide pins  200  in slots  202 . The X-linkage  196  keeps the arms parallel, as the arms opened and closed. 
       FIG.  14    shows a portion of the tool embodiment at the juncture between the handle portion  300  and the arms  192  and  194 . A flexure element formed of an elongated, cantilevered arm  305  is positioned at the juncture in a manner that interacts with the arms  192  and  294  in a manner that maintains the arms in a parallel position when the arms are clamping something, such as when clamping tissue. The arm  305  is mechanically coupled to a structure positioned between the arms of the handle portion  300 . 
       FIG.  15    shows a perspective, enlarged portion of one of the arms  192 .  FIG.  16    shows a side view of the arm  192 . An electrode  307  removably attaches to the arm  192  along the length of the arm  192 . In an example embodiment, the electrode  307  includes one or more protrusions  309  that lockingly mate with complementary key-shaped openings  311  of the arm  192 . For example, the protrusions  309  can mate with the openings  311  in a slide and lock manner such that the protrusions are inserted into the openings  311  and then are slide along a key-shaped portion of the openings to lock therein. In another embodiment, the protrusions snap into and lockingly engage with the openings such as in a press fit manner. Other mechanisms for coupling and locking the electrode to the arms are within the scope of this disclosure. For example, the electrode may slide onto the arm such as in a front-loading manner such that the electrode slides into or onto the arm from the front of the device. In another embodiment, the protrusions are on the arm and the openings are on the electrode. A similar arrangement can be used for the other arm  194 . 
     In an embodiment, at least a portion of the device is disposable and another portion of the device is reusable. For example, as shown in the embodiment of  FIG.  17   , the tool includes a disposable pair of removable arms or jaws  313  that removably mate with a handle portion  300  that is reusable. The arms  313  can removably mate with or otherwise removably couple to the handle portion  300 . This can occur using any of a variety of mechanisms, such as in a sliding tongue and groove mechanism wherein the arms slidingly engage and lock with the handle portion  300 . 
     As used here, unless otherwise stated, “in contact with” means elements actually or nominally touching each other, such as elements 1 or 2 mm apart. The term “linearly” is used here to distinguish from pivotal movement, and does not connote any geometrically precise linear characteristic. The term “joined”, “attached” or “connected to” means temporarily or permanently physically linked with, or integral with, as with different sections of a single integral element. 
     The elements described above may of course also be applied in other products having similar elements, movements or requirements. These include, for example door hinges, to create a weather tight seal, or as a hinge on a trunk or case, or a briefcase allowing for expansion when filled over capacity. The elements and principles described may also be applied to a gas or fluid tank cap to regulate or relieve pressure, or as a pouch sealer to equalize pressure on the seal. 
     While this specification contains many specifics, these should not be construed as limitations on the scope of an invention that is claimed or of what may be claimed, but rather as descriptions of features specific to particular embodiments. Certain features that are described in this specification in the context of separate embodiments can also be implemented in combination in a single embodiment. Conversely, various features that are described in the context of a single embodiment can also be implemented in multiple embodiments separately or in any suitable sub-combination. Moreover, although features may be described above as acting in certain combinations and even initially claimed as such, one or more features from a claimed combination can in some cases be excised from the combination, and the claimed combination may be directed to a sub-combination or a variation of a sub-combination. Similarly, while operations are depicted in the drawings in a particular order, this should not be understood as requiring that such operations be performed in the particular order shown or in sequential order, or that all illustrated operations be performed, to achieve desirable results. 
     Although embodiments of various methods and devices are described herein in detail with reference to certain versions, it should be appreciated that other versions, embodiments, methods of use, and combinations thereof are also possible. Therefore the spirit and scope of the appended claims should not be limited to the description of the embodiments contained herein.