Cable stripper

Abstract

A blade stripper has a displaceable blade carriage, which is normally biased toward a cable support to automatically accommodate differently dimensioned jacketed cables, and a pair of coaxial handles spaced apart along a longitudinal axis of the blade stripper to allow the user to apply pulling forces directed substantially perpendicular to the longitudinal axis for producing a linear cut in the jacket.

Description

BACKGROUND OF THE INVENTION

[0001] 1. Field of the Invention

[0002] The invention relates to hand tools, and in particular, the invention relates to a portable cable stripper automatically adjustable to accommodate differently dimensioned jacketed cables and safely removing jackets from these cables in a simple and efficient manner.

[0003] 2. Background of Technological Field

[0004] It is difficult to imagine our life without a limitless variety of electro-powered devices. What is less obvious is that all of these devices are provided with innumerous cables connecting devices to one another and to power sources as well as providing communication between separate components within the same device. Many cables have jackets having outer diameters varying from very small to gigantic. Cable connections involve stripping jackets from cables to be connected, wires and conductors, and, quite often, such stripping is an onerous and unsafe task.

[0005] U.S. Pat. No. 6,308,417, which is commonly assigned with the present application and incorporated herein by reference, discloses a cable stripper which enjoys a well-deserved success. However, the cable stripper disclosed in this patent has a complex structure associated with a relatively high manufacturing cost.

[0006] It is, therefore, desirable to provide a cable stripper having a simple structure that is easy to adjust, safe to use, and that can provide an easy access to difficult to reach locations.

3. SUMMARY OF THE INVENTION

[0007] It is, therefore, an object of the invention to provide a portable cable stripper having an easily adjustable structure for reliably holding differently dimensioned jacketed cables during a stripping operation.

[0008] Another object of the invention is to provide a portable cable stripper having a resiliently-biased blade assembly to prevent the cable to be stripped from being damaged during a stripping operation.

[0009] Yet a further object of the invention is to provide a portable cable stripper having a guide assembly for displacing the cable stripper along a straight cutting line.

[0010] Consistent with the foregoing objects, the inventive portable cable stripper is automatically adjusted to grip differently dimensioned jacketed cables with a resiliently-biased blade holding carriage. To accomplish it, the blade holding carriage slides towards the periphery of the jacketed cable and presses against it so as to position the jacketed cable in a cutting position, in which the cable and the cable stripper can move relative to one another only upon applying an external force.

[0011] An advantage of the resiliently biased blade holding carriage it provides a reliable and easily adjustable grip of the portable cable stripper on a jacketed cable, even when such a cable is inconveniently located.

[0012] According to another aspect of the invention, a blade assembly is provided with a resilient element retracting a blade from a cutting position after a cut has been completed.

[0013] This improvement facilitates an easy switch of the blade between a straight cut, a circumferential cut and a spiral cut. Furthermore, the biased blade is automatically retracted from its cutting position after a lock on the blade is released. Accordingly, the risk that the user can be cut during the switch of the blade positioning is substantially minimized.

[0014] In accordance with a further improvement, the portable cable stripper has a convenient guiding assembly stirring the blade along a desired straight line during the stripping operation. This is accomplished by a holder engageable by one hand of the user and mounted on one of the opposite ends of the cable stripper. The opposite end of the cable stripper has an elongated guide column shaped and dimensioned to provide a convenient surface engageable by other hand of the user.

[0015] As a result of the guiding assembly, pulling forces exerted by the hands of the user are uniformly distributed along opposite segments of the circumference of the cable to be stripped, which, in turn, prevents twisting of the cable stripper relative to the cable to be stripped.

BRIEF DESCRIPTION OF THE DRAWINGS

[0016] These and other objects, features and advantages will become more readily apparent when reference is made to the following description taken in conjunction with the accompanying drawings, in which:

[0017] FIG. 1 is an isometric view of the cable stripper in accordance with the present invention;

[0018] FIG. 2 is an isometric view a portion of the inventive cable stripper illustrating cable guide and blade carriage assemblies;

[0019] FIG. 3 is an isometric view of a blade housing;

[0020] FIG. 4 is an isometric view of a blade holder; and

[0021] FIG. 5 is an isometric view of the blade assembly.

SPECIFIC DESCRIPTION

[0022] Referring to FIGS. 1-5 in general, and to FIG. 1, in particular, a portable cable stripper 10 includes a V-shaped cable support 12 for receiving a cable to be stripped, a guide column 14 removably attached to the cable support, a blade-holding carriage 16 slidable along the guide column and a guide assembly including a handle 20, which is attached to an outer side of the cable support.

[0023] The portable cable stripper is a labor-saving tool adjustable to remove jackets from rigid fiber optic and plastic jacketed cables having an outer diameter which may vary from about {fraction (3/16)}″ to 2″. In operation, the user initially sets a desirable distance at which a blade 70 (FIG. 5) should penetrate the jacket of the cable. Following it, the blade carriage 16 is pulled outwards from the V-shaped cable support 12 to form a space sufficient to receive the cable, and once the cable is placed on the cable support, the blade carriage automatically slides towards and presses against the periphery of the jacket. Accordingly, the cable is locked between the cable support 12 and the blade carriage 16.

[0024] As illustrated in FIGS. 1 and 2, automatic displacement of the blade carriage 16 toward the cable to be stripped is caused by a spring 68 mounted on a central post 66, better shown in FIG. 2, and biasing the blade carriage towards the cable support 12. The post 66 is removably mounted on one side of the cable support and traverses a central hole formed in a flange 22 of the guide carriage, which, thus, has an L-shape. The post further has a thickened outer end sized and shaped to form a seat for the outer end of the spring 68, the opposite end of which urges against the flange 22 of the blade guide so as to push the latter towards the cable placed on the cable support.

[0025] A desired position of the blade carriage can be registered by a carriage lock 26 provided with a screw 84, which is actuated by a handle 82 so that the screw 84 engages a threaded portion of locking cylinder 58 (FIG. 1). The desired position is ensured when the locking cylinder 58 is pulled against the central post 66.

[0026] Guide recesses 24 formed on the opposite sides of the flange 22 provide linear displacement of the blade carriage in a plane perpendicular to a tangent to the periphery of a circular cable. Preferably, the bottoms of the guide recesses 24 each have a respective surface extending complementary to a peripheral surface of the side posts of the guide column 14, which are, as shown in FIG. 1, are tubular. However, the cross-section of the posts is not limited to any particular configuration and may be, for example, polygonal.

[0027] Disassembly of the cable stripper 10 is simplified by attaching inner ends of the side posts of the guide column 14 (FIG. 1) and of the central post 66 (FIG. 2) to a flange 92 of the cable support 12 by fasteners 90 extending through openings 88, which are provided on the flange 92. The guide recesses 24, better illustrated in FIG. 2, are laterally open to facilitate the installation of the guide column 14, which is U-shaped and, thus, features a loop easily engageable by the user's fingers during the transportation of the cable stripper. The bottoms of the guide recesses and the side holes 88 have a uniform radius and are aligned with one another to ensure that the guide column 14 extends substantially perpendicular to a plane in which the guide support 12 lies.

[0028] The blade carriage 16 carries a blade assembly 18 including a blade positioning dial ring 56 (FIG. 1), which is rotated by the user to establish a desired position corresponding to the desired depth of penetration of the blade into the jacket of the cable to be stripped. The dial ring 56 is operative to rotate to an initial position corresponding to a zero penetration of the blade 70 which is established when the zero “O” mark of the scale formed on the dial ring is juxtaposed with a top edge of index 38 (FIG. 2). A releasable ring lock 30, which is mounted on the side of the blade carriage opposite its flange 22, is operable for locking the dial ring in a position corresponding to the desired penetration of the blade. The ring lock 30 is a spring-biased structure, which, in a normal or locking position, prevents rotation of the dial ring 56, as will be explained below.

[0029] A resilient element of the ring lock, such as a spring 32 (FIG. 1), urges the ring lock 30 towards the locking position. The ring lock is substantially a plate-like element having a center recess 31 (FIG. 2) frictionally engaging the dial ring 56 in the locking position of the ring lock 30. In response to an external force, the ring lock 30 can move out of the locking position and release the dial ring 56, so that the latter can be further rotated the desired position corresponding to the selected depth of the blade penetration. Preferably, the index 38 is attached to the ring lock 30 and extends outwards from the blade carriage 16 to terminate flush with the scale for the convenience of the user. The dial ring has a structured surface provided with alternating ribs and troughs slidably engaging a v-shaped edge of the index 38 to indicate the number of turns corresponding to the desired depth of the blade penetration into the cable's jacket. After the desired position has been set, an external force is ceased, and the ring lock returns to its locking position. Sliding motion of the ring lock 30 relative to the guide carriage 16 becomes possible due to a pair of spaced oblong holes 34 (FIG. 2) formed on the ring lock 30 and traversed by fasteners 36, which are removably attached to the blade carriage 16. The fasteners 36 are shaped and dimensioned so as to allow the ring lock's displacement, which is restricted only by the size of the holes.

[0030] The blade assembly 18 further includes a hollow blade housing 40 (FIGS. 2, 3 and 4) and a blade holder 60, better illustrated in FIG. 5. The blade housing 40 extends through an opening formed in the blade carriage 16 and has a hollow interior receiving the blade holder 60 which is sized to controllably rotate within the blade housing, as will be explained below. The periphery of the blade housing 40 is threaded to mesh with a threaded inner surface of a blade cap 100 (FIG. 1), which also acts as a blade lock, as will be explained below.

[0031] A U-shaped recess 54 (FIG. 3) formed in the periphery of the blade housing 40 provides a guide channel for a lever 28, which is removably fixed to the blade holder 60 by a thumb screw 52 (FIG. 1) so as to displace the blade 70 between numerous positions corresponding to radial, axial and spiral cuts of the jacket in the following manner. To make a straight axial or radial cut, the blade holder 60 is provided with a first threaded hole 48 spaced at a 90° angle from a hole 46 traversed by a fastener which interconnects the blade 70 and the blade holder 60. As the blade holder 60 is inserted through the hollow interior of the blade housing 40, the hole 48 is accessible through the U-shaped recess 54 (FIG. 3) and receives the threaded end of the thumb screw 52. Accordingly, the U-shaped recess 54 is formed with a pair of side channels spaced at a 90° angle from one another and a bridging channel extending between the juxtaposed ends of the side channels.

[0032] Depending on which of the side channels of the U-shaped recess 54 receives the shaft of the lever 28, the blade holder 60 along with the blade 70 assume a radial cut position, in which the blade is turned at a 90° angle with respect to the axis of the cable, or an axial cut position, wherein the blade 70 extends parallel to the axis.

[0033] Turning to FIGS. 4 and 5, the inner end 102 of the blade holder 60 is recessed to receive the blade 70 removably attached to the inner end by a fastener and extending substantially flush with the rest of the blade holder. The outer end 64 of the blade holder provides a seat for one end of a spring 62, the other end of which embraces a flange 44 (FIG. 1) attached to the inner side of the blade carriage 16 so that the spring 62 biases the blade holder 60 away from the cable support 12. As a consequence, the user applies a force overcoming the spring force and sufficient to guide the lever 28 along one of the side channels of the U-shaped recess 54 and extending beyond a flange 42 of the blade housing 40 exactly at the desired distance. The blade cap 100 is then screwed in on the blade housing 40 to lock the lever 28 between its inner surface and the opposing surface of the dial ring 56 and remains in this position during the cutting operation. The spring-biased structure of the blade holder allows the user to easily change the current cutting position of the blade 70 without detaching the cable stripper 10 from the cable by first releasing the blade cap 100 and then, by readjusting the thumb screw.

[0034] Another hole 50 (FIG. 4) can be tapped in the blade holder 60 at an angular distance from both holes 48 and 46 to provide a spiral cut, if needed. If a cable to be processed in not round, a wave spring 108 (FIG. 1) keeps the blade support in contact with this cable for constant blade penetration while the entire blade assembly is being adjusted.

[0035] An axial cut requires that forces applied by the user to the cable stripper be uniform and unidirectional. The handle 20 attached to the outer side of the cable support 12 and the blade cap 100 constitute the guide assembly meeting the requirement for the desired axial cut. The blade cap 100 is dimensioned to provide a sufficiently large surface allowing the user to have a comfortable grip by one of the user's hands, whereas the other hand can conveniently hold the handle 20. To ensure the right distribution and direction of the pulling forces, the point of attachment of the handle 20 is located on a central axis 104 extending through the blade cap 100 and through the blade 70. While different shapes of the handle can be successfully used, a ring-shape handle swingably attached to the cable support 12 is preferred.

[0036] While this disclosure has described various aspects of the present invention, the latter is not limited thereto, and is susceptible to numerous changes and modifications as known to those skilled in the art. Therefore, the invention is not limited to the details shown and described herein, and includes all such changes and modifications as are encompassed by the scope of the appended claims.

Claims

1. A cable stripper comprising: an elongated column; a cable support detachably coupled to one end of the elongated column; a blade carriage provided with a blade assembly and slidably mounted on the elongated column, the blade carriage and the cable support being displaceable relative to one another to form a space therebetween sufficient to selectively receive differently dimensioned jacketed cables, the blade carriage being resiliently biased towards the cable support so that when a cable to be stripped is inserted into the space, the cable support and blade carriage press against the cable in opposite directions while the cable's jacket is being cut by the blade assembly.

2. The cable stripper according to claim 1, wherein the guide column has a central post provided with a seat on one end and receiving a carriage spring, the carriage spring being braced between the blade carriage and the seat to bias the carriage toward the cable support.

3. The cable stripper according to claim 1, wherein the blade assembly includes a hollow blade housing mounted on the blade carriage, and a blade holder traversing the hollow blade housing and resiliently biased away from the end of the hollow blade housing facing the cable support.

4. The cable stripper according to claim 3, wherein the blade holder has opposite ends one of which is thicker than the other end which is coupled to the blade, the cable stripper further comprising a blade spring extending along the blade holder and having opposite ends braced against the one end of the blade holder and the blade carriage to bias the blade holder within the blade housing.

5. The cable stripper according to claim 4, wherein the blade housing has a threaded periphery and a U-shaped recess formed in the periphery and forming angularly spaced guide channels to provide access to the interior of the blade housing.

6. The cable stripper according to claim 5, further comprising a hollow lever traversed by a thumb screw coupled to the blade holder, the hollow lever extends through the recess and operative to selectively move along the spaced guide channels to establish a radial cutting position and an axial cutting position of the blade.

7. The cable stripper according to claim 6, further comprising a blade cap having an inner threaded surface meshing with the threaded periphery of the blade housing and displaceable relative to the blade housing to lock the hollow lever in a desired position corresponding to one of the radial or axial cutting positions of the blade.

8. The cable stripper according to claim 6, wherein the blade holder is provided with two angularly spaced holes selectively engaged by the thumb screw so that when one of the holes is engaged by the thumb, the blade can be switched between the radial and axial cutting positions, and when the other hole is engaged by the thumb screw, the blade is in a spiral cutting position.

9. The cable stripper according to claim 1, further comprising a dial assembly rotatably mounted on the blade housing to enable the blade assembly to penetrate the jacket of the cable at a predetermined depth.

10. The cable stripper according to claim 7, wherein the dial assembly includes a dial ring mounted on the blade housing between the blade carriage and the blade cap, so that when the blade cap is displaced toward the dial ring, the hollow lever is locked between the opposing faces of the dial ring and the blade cap.

11. The cable stripper according to claim 10, wherein the dial ring has a scale provided on the face of the dial ring facing the blade cap and indicating a desired penetration of the blade into the jacket upon rotating the dial ring in an operative position, the cable stripper further comprising a ring lock mounted on the blade carriage and biased in a lock position, wherein the dial ring is locked against further rotation after having been rotated in the operative position.

12. The cable stripper according to claim 11, wherein the ring lock has a plate-like body formed with spaced oblong holes and extending between opposite ends, one of the ends being provided with a resilient element extending between the blade carriage and the one end, and the other end extending from the blade carriage to terminate flush with the scale and to provide an index for establishing the operative position of the dial ring.

13. The cable stripper according to claim 12, further comprising a plurality of fasteners each extending through a respective oblong hole and removably attached to the blade carriage so that when an external force is applied to the one end of the plate-like body, the ring lock is displaceable until the extremities of the oblong holes engage the fasteners.

14. The cable stripper according to claim 1, further comprising a handle pivotally attached to a side of the cable support facing away from the blade carriage, the handle having a point of attachment lying on a central axis which extends through the guide support, the blade carriage and the blade assembly.

15. A cable stripper comprising: an elongated column; a cable support detachably coupled to one end of the elongated column; a blade carriage provided slidably mounted on the elongated column, the blade carriage and the cable support being displaceable relative to one another to form a space therebetween sufficient to receive differently dimensioned jacketed cables; and a blade assembly provided with a resiliently biased blade and mounted on the blade carriage to travel therealong along the elongated column, the resilient blade being biased away from the blade carriage in a rest position of the blade to prevent contact between the user and the tip of the blade.

16. A cable stripper comprising: an elongated column; a cable support detachably coupled to one end of the elongated column and centered along a longitudinal axis; a blade carriage coaxial with the cable support and slidably mounted on the elongated column, the blade carriage and the cable support being displaceable relative to one another to form a space therebetween sufficient to receive differently dimensioned jacketed cables; a blade coaxial with and mounted on the blade carriage to move therealong; a blade cap removably attached to the blade carriage and extending in one axial direction from the blade; and a handle attached to the cable support so that a point of attachment lies on the longitudinal axis and extending generally in opposite axial direction, so that when the blade penetrates into the cable to be stripped, the handle and the blade cap provide a reliable grip for the user as the cable stripper and the cable move relative to one another.