Abstract:
A cable-stripping tool includes two parts that can be moved linearly in relation to each other, each of the parts including an opening which can accommodate a cable when the openings are in mutual alignment. The first part carries a cutting blade and has a support arrangement with a ring that, when rotated about an axis, adjusts a cutting depth of the blade. A spring element functions to bias the parts in a direction away from each other, while enabling the two tool parts to be brought together against the spring bias by a user squeezing with only one hand so that the cable to be stripped can be inserted into the tool intermediate the two ends to which force is applied.

Description:
BACKGROUND OF THE INVENTION 
   1. Field of the Invention 
   The present invention relates to a cable-stripping tool. 
   2. Description of the Related Art 
   Known devices/tools for cable stripping are of a kind having first and second parts which are movable linearly towards and away from each other, a cutting blade which is carried by the first part, a support element which is carried by the first part, an abutment which is carried by the second part, and spring means which mutually bias the first and second parts in their relative movement directions. Using a through-passing opening provided for receiving a cable, such cable can be inserted between the abutment and the cutting blade when the first and second parts are mutually displaced in their respective directions against the bias of the spring element, such that the cable is clamped between the abutment on the one hand and the cutting blade on the other hand when the tool is relieved of load. The distance between the cutting blade and the adjacent part of the support element defines the depth to which the cutting blade penetrates the cable, and at least one of the first and second parts is ring-shaped. 
   Cable-stripping devices of the aforesaid kind are known from GB-A-22 15 143 and U.S. Pat. No. 4,640,009 for instance. Such devices/tools include two parts which are movable linearly in relation to each other and which carry respectively an abutment means and a cutting blade with an associated cable support that restricts the cutting depth of the blade. Biasing means urge the parts towards each other, so that a cable placed between the abutment means and the blade will be clamped against the blade. Tools of this kind function to establish a radial cut around the cable. The tool has a finger opening spaced from a tool guide that receives the cable, so that a user can readily twist the tool, and therewith the blade, around the cable. 
   One drawback with the known tools is that they are relatively difficult to open against the spring bias, in order to allow insertion of a cable to be stripped. For instance, GB-A 22 15 143 teaches spring means that bias the linearly movable main parts of the tool towards one another. In order to open the tool, the user needs to move the tool parts apart, which is difficult to achieve even though one part of the tool can be gripped and the other part has a projection/dogging element that enables the second part to be pressed away from the first part with the thumb of the hand gripping the tool. 
   SUMMARY OF THE INVENTION 
   Accordingly, one object of the invention is to provide a tool of the aforedescribed kind that can be readily and comfortably manoeuvred with one hand when placing the cable into the tool. 
   A further object is to provide a tool that will enable the cutting depth of the blade to be set in a positive and comfortable fashion and, at the same time, stabilise the position of the cable or cable on the support. 
   These objects are achieved by means of the invention. 
   According to one important feature of the invention, the tool arrangement is such that the main parts of the tool are biased in a direction away from each other by the spring element, and can be moved towards each other against the action of the spring bias, by virtue of the user squeezing the tool in the direction of relative movement of said parts with one hand, by actuation of the opposing ends of the tool in the movement direction of said parts. The tool shall have a length which enables it to be gripped comfortably in the user&#39;s hand for squeezing said parts together in the illustrated manner. The tool will also preferably include a rotatable support element which includes around its periphery supports which together with a fixed cutting blade define different blade cutting depths. The tool will also limit the possibility of movement of the cable along the support element. This is achieved by virtue of the fact that the support element has the form of a ring whose inner periphery carries the various supports. The ring-shaped support element may carry signs which indicate the cutting depth that has been established in the instant position of rotation of the ring in relation to a read-off mark on the tool-part at which the support element is rotatably mounted. 
   The inner periphery of the support element may have a polygonal shape around at least a part of its perimeter, wherein the sides of the polygon define supports located at different distances from the rotational axis of the support element, i.e. from the blade edge when the support elements are situated adjacent the cutting blade. 
   The supports which lie adjacent to a support that is in a co-operative position with the cutting blade restrict the possibility of the cable sliding along the support concerned. 
   The abutment may have a wedged-shape so as to prevent displacement of the cable circumferentially in relation to the abutment. 
   The present invention may be further embodied such that the support element includes a ring-shaped support element that defines the through-passing opening, the ring-shaped support element being a ring which is mounted in the first part for rotation about its axis. The support element includes an abutment which is linearly guided generally radially in respect of the ring, the abutment having a cam follower and the ring having a cam which is in engagement with the cam follower and which is spaced from the center of the ring at a distance which varies around the periphery of the ring so as to enable a cutting depth to be set that corresponds to the rotational position of the ring relative to the first part. 
   The abutment may be carried by the radially and inwardly facing side of the cam, via the cam follower. In addition, a spring element may be adapted to bias the abutment into contact with the cam. 
   The present invention may further be embodied such that the ring has an outer peripheral surface which lies against a shoulder on the first part in the combined state of the parts. The outer surface of the ring includes a recess which receives the shoulder in a corresponding rotational position of the ring and therewith enables the parts to be brought together through a further distance corresponding to the depth of the recess. 
   A holder carrying the cutting blade may be inserted from without into a corresponding guide channel to an operating position in the tool. The inner end of the holder includes a latch arm that has a latch hook which grips around a latch strip for holding the holder in the channel. The inner end-portion of the holder has a wedge-like surface which is able to coact with a post on the second tool part when the two parts are combined and the shoulder is in alignment with the recess on the ring. 
   According to a further embodiment, the wedge-like surface includes two parts of different inclinations, such that the post first co-acts with the steeper surface so as to apply a significant axial displacement force on the holder and therewith move the holder out of the channel so as to release the holder latching mechanism. 
   The invention will now be described in more detail by way of example and with reference to the accompanying drawings. 

   
     BRIEF DESCRIPTION OF THE DRAWINGS 
       FIG. 1  is a schematic plan view of an inventive tool. 
       FIG. 2  is a schematic section view of the tool, taken in a plane which is parallel with the plan view of  FIG. 1 . 
       FIG. 3  illustrates the cable stripping opening of the tool exposed for insertion of a cable thereinto. 
       FIG. 4  is a schematic section view of one tool variant, wherein the section can be assumed to lie in a symmetry plane with respect to the tool. 
       FIG. 5  is a schematic view taken on the line  5 — 5  in  FIG. 4 . 
       FIG. 6  is a partial front view of one tool variant. 
       FIG. 7  is a schematic view taken on the line VII—VII in  FIG. 4 . 
       FIG. 8  is a sectional view taken on the line VIII—VIII in  FIG. 7 . 
   

   DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS 
   Further scope of applicability of the present invention will become apparent from the detailed description given hereinafter. However, it should be understood that the detailed description and specific examples, while indicating preferred embodiments of the invention, are given by way of illustration only, since various changes and modifications within the spirit and scope of the invention will become apparent to those skilled in the art from this detailed description. 
   The tool  10  includes two main parts  1 ,  2  which are linearly movable in relation to one another, in a direction that stretches between the short ends of the tool. A ring  4  is rotatably mounted in one main part  1 . The outer periphery  15  of the ring  4  is received in a corresponding opening  42  through the part  1 . The ring  4  has an outwardly projecting peripheral flange  45  that includes markings  46  spaced peripherally around said flange and capable of being read against a read-off line  17  on the part  1 . The flange  45  is exposed outwardly of the part  1 , so as to enable the ring  4  to be readily rotated manually, via the flange  45 . 
   The inner wall of the ring  4  has a polygonal configuration which is comprised of a number of supports  41  that lie at different distances from the rotational axis  27  of the ring  4 . The part  1  carries a cutting blade  3  whose cutting edge is exposed in the ring cavity at its portion facing towards the part  2 . 
   The part  2  extends into the upper portion of the part  1  through the medium of a pair of posts  21 , and is connected to a crosspiece  22 . The part  1  has a recess which receives the portions  21 ,  22  of the part  2 . The upper end wall  18  of the part  1  defines an abutment surface  11  for a pair of spring elements  5 , which also act on the crosspiece  22 . The springs  5  include two spring legs and a winding turn located between said legs and received on an associated guide pin  16  in the part  1 . The springs  5  form pressure springs that act between the end wall  18  and the crosspiece  22  for moving the parts  1 ,  2  away from each other. A latching element  14 ,  25  prevents the parts  1 ,  2  from being parted by the springs  5  beyond a chosen limit position. The crosspiece  22  forms an angled abutment  23 . The part  2  has a finger opening  20  at its exposed end, the axis of said opening being parallel with the axis of the ring  4 . 
     FIG. 3  shows that the placement of the supports  41  around the inner perimeter of the ring  4  and the rotational mounting of the ring  4  in the part  1  enables a limited length of the tool  10  to be achieved in the relative direction of displacement of the parts  1 ,  2 , so that the tool  10  can be comfortably gripped between the index finger  61  and the thumb  62  of one hand for squeezing of the tool  10  against the action of the springs  5 . When so squeezed, the abutment  23  will expose the opening of the ring  4  intermediate the two ends to which force is applied and therewith enable the cable to be inserted therein. When the compression load on the tool is thereafter relieved, the abutment  23  drives the cable  7  against the cutting blade  3 , which cuts into the cable  7  to a depth defined by the support  41  located at that instance in the co-operating position relative to the blade edge  3 . It will be noted that the cutting depth of the blade  3  can be set easily, by rotating the ring  4  via its exposed ring-flange  45 . When the cable  7  is firmly gripped between the abutment and the blade, the operator is able to insert a finger into the opening  20  of the part  2  and turn the tool  10  around the cable  7  through one revolution, whereafter the tool can be displaced axially towards the end of the cable to strip-off the cut cable casing. Alternatively, the tool can be squeezed to enable it to be removed from the cable  7 . 
     FIG. 1  shows the tool  10  in a squeezed state, and shows that the edge of the cutting blade is exposed in the opening of the ring  4 , when viewing the tool in the axial direction of the ring. The abutment  23  is shown in the upper part of the ring opening for the sake of clarity. When the load on the tool is removed, i.e., when the first and second parts are no longer pressed toward one another by the user, the abutment  23  moves towards the cutting blade  3 . The cutting blade  3  may be replaceable and swapped with blades whose edges have a different angle to the axis of the ring, so as to provide other cutting-depth ranges. The cutting blade  3  is conveniently perpendicular to the direction of relative displacement of the tool parts, so that the cutting depth of the blade will be generally the same in both possible directions of rotation of the tool around the cable  7 . 
   Alternatively, the depth of the blade  3  can be controlled or adjusted by the modification shown in  FIGS. 4 and 5 . The modification includes a support element  148  which is guided linearly by a guide  150  in a direction towards the centre region of the ring  4 . The support element  148  may have a generally cupped-shape, i.e. include a bottom and side-walls for stable reception of a cable whilst the tool  10  is pressed around said cable. The support element  148  includes a cam follower  50  which engages a cam  48  on the ring  4 . The distance of the cam  48  from the centre of the ring varies around the ring perimeter, and the cam can thus displace the support element  148  to different distances from the cutting blade  3 . The support element  148  is shown to be biased by a spring in a radially outward direction, while the support element  148  rests on the cam follower  50  at the same time. 
     FIG. 6  shows the ring  4  fitted in the part  1 , and also shows that the outer perimeter  42  of the ring supports against a shoulder  51  on the part  2  when the parts  1 ,  2  are combined, with the exception of one position of rotation of the ring  4  in which a recess  98  in the periphery  42  of the ring  4  receives the shoulder  51 . This position of rotation may correspond to an end position for rotation of the ring  4 , which is indicated in  FIG. 6  by a marking X on the ring  4  lying in alignment with an indicator  77  on the part  1 . 
   In this particular rotational position of the ring  4 , the parts  1 ,  2  can be brought further together through a distance corresponding to the depth of the recess  98 . 
   As will be seen from  FIG. 4 , the part  1  includes a through-passing channel  31  for accommodating a blade holder  30  which grips the cutting blade  3 . The blade holder may have the form of a plastic body which receives the blade  3  and which forms a finger-grip  32  at one end of the channel  31 . The finger-grip end  32  is shown to be flush with the outside of the part  1  when the blade holder unit  30  is fully inserted into the channel  31 . Provided on the insertion end of the unit  30  is a further plastic body  34  which may be an integral part of a plastic-portion  33  that receives the bottom portion of the blade  3  and connects the parts  32 ,  34  as well as the side parts  37 . The part  34  is extended by a flexible arm  35  which carries a latch hook  36  which is shown to grip over a latch strip  38 . The underpart of the body  34  is shown to consist of a wedge-shaped surface that co-acts with a post  80  connected to the part  2 . 
   The wedge-shaped surface of the body  34  is shown to comprise two adjacent oblique surfaces  91 ,  92  of different inclinations, and the post  80  is shown to have two corresponding oblique surfaces  81 ,  82 . The steep surfaces  81 ,  91  first engage one another when the shoulder  51  engages the recess  98  ( FIG. 6 ) and then promote axial displacement of the unit  30  to the left in  FIG. 7 , wherein the latch hook  36 , which may optionally have an oblique latching surface, and the arm  35  are able to pass free from the latch strip  38 . When the less steep wedge-like surfaces  82 ,  92  engage one another, the unit  30  is driven out of the channel  31  and therewith allow the unit to be gripped at its grip end  32  for withdrawal and replacement. When a new unit  30  is placed in the channel  31 , the arm  35  and the latch hook  36 , which has a wedge-shaped surface, can be bent out to engage behind the latch strip  38 . The latch hook  36  and the arm  35  are arranged, together with the latch strip  38 , to hold the blade holder unit  30  firmly in the channel  31 . 
   The invention being thus described, it will be apparent that the same may be varied in many ways. Such variations are not to be regarded as a departure from the spirit and scope of the invention, and all such modifications as would be recognized by one skilled in the art are intended to be included within the scope of the following claims.