A CABLE STRIPPING TOOL FOR ELECTRICAL CABLES
20180323588 ยท 2018-11-08
Inventors
Cpc classification
H01B7/368
ELECTRICITY
International classification
H02G1/12
ELECTRICITY
Abstract
A cable stripping tool for use with electrical cables comprising an inner core and at least one outer sheath. The cable stripper includes a body including a cable retaining portion having a rotational axis defined therethrough. The cable retaining portion is configured to receive a cable such that its longitudinal axis is coaxial with the rotational axis. The cable stripper also includes first and second cutting blades movable transversely relative to the rotational axis between a retracted position and a cutting position, the cutting blades each having a blade edge. The blade edges of the first and second blades are axially spaced from each other relative to the rotational axis and are arranged such that in the cutting position the first cutting blade is spaced a first radial distance from the rotational axis and the second blade is spaced a second radial distance from the rotational axis that is greater than the first radial distance. The cable stripping tool is rotatable about the rotational axis when the cutting blades are in the cutting position to cause the blades to cut around the entire circumference of the cable.
Claims
1. A cable stripping tool for use with electrical cables comprising an inner core and an outer sheath, said cable stripping tool comprising: a body including a cable retaining portion having a rotational axis defined therethrough, wherein the cable retaining portion is configured to receive a cable such that a longitudinal axis of the cable is coaxial with the rotational axis; and first and second cutting blades movable transversely relative to the rotational axis between a retracted position and a cutting position, the first and second cutting blades each having a blade edge; wherein the blade edge of the first and second cutting blades are axially spaced from each other relative to the rotational axis and are arranged such that, in the cutting position, the first cutting blade is spaced a first radial distance from the rotational axis and the second cutting blade is spaced a second radial distance from the rotational axis that is greater than the first radial distance, wherein the cable stripping tool is rotatable about the rotational axis when the first and second cutting blades are in the cutting position to cause the first and second cutting blades to cut the outer sheath around an entire circumference of the cable.
2. The cable stripping tool according to claim 1, wherein the cable retaining portion includes a stop member arranged to longitudinally locate the cable when inserted into the cable retaining portion.
3. The cable stripping tool according to claim 2, wherein the first cutting blade is longitudinally closer to the stop member than the second cutting blade.
4. The cable stripping tool according to claim 2, wherein the cable retaining portion comprises a channel extending into a body section having an opening at located at one end configured to receive the cable and an opposing end that is closed, thereby forming the stop member.
5. The cable stripping tool according to claim 4, wherein the channel comprises a plurality of longitudinally extending and annularly spaced ribs.
6. The cable stripping tool according to claim 4, further comprising a blade actuator pivotally mounted to the body section, wherein the first and second cutting blades are mounted to the blade actuator, and wherein pivoting of the blade actuator relative to the body section moves the first and second cutting blades between the retracted position and the cutting position.
7. The cable stripping to according to claim 6, wherein the body section includes a cylindrical wall defining an aperture through the body section having an aperture axis parallel with and spaced from the rotational axis, the blade actuator being pivotally mounted about the cylindrical wall.
8. The cable stripping tool according to claim 7, further comprising the stop member arranged to limit a rotational movement of the blade actuator between the retracted position and the cutting position.
9. The cable stripping tool according to claim 8, wherein the stop member extends from the cylindrical wall and is received with a corresponding channel in the blade actuator having a length defining stop limits.
10. The cable stripping tool according to claim 7, wherein the cylindrical wall is configured to receive a user's finger and an inner surface of the cylindrical wall defines a curved contact surface configured to engage the user's finger to rotate the cable stripping tool around the cable.
11. The cable stripping tool according to claim 6, wherein the first and second cutting blades are circular and arranged concentrically, wherein the first cutting blade has a diameter greater than the second cutting blade, and wherein a central axis of the first and second cutting blades is parallel with the rotational axis.
12. The cable stripping tool according to claim 11, wherein the first and second cutting blades are spaced from a pivotal axis of the blade actuator such that the central axis of the first and second cutting blades pivots along an arcuate path that intersects the rotational axis.
13. The cable stripping tool according to claim 12, wherein the blade actuator is housed within the body and includes a trigger portion that projects out of the body section and is arranged to be depressed by a user to move the first and second cutting blades to the cutting position.
14. The cable stripping tool according to claim 4, wherein the first and second cutting blades are movable between the retracted position, an intermediate cutting position and the cutting position and wherein a radial distance of the first and second cutting blades from the rotational axis is greater at the intermediate cutting position than the cutting position.
15. The cable stripping tool according to claim 14, further comprising a blade actuator to which the first and second cutting blades are mounted, wherein movement of the blade actuator relative to the body section moves the first and second cutting blades between the retracted position, the intermediate cutting position, and the cutting position, said cable stripping tool further comprising a releasable locking element arranged such that movement of the blade actuator from the retracted position to an intermediate position the locking element locks the blade actuator in the intermediate cutting position, thereby preventing return to the retracted position, and further movement of the blade actuator to the cutting position causes the locking element to lock the blade actuator in the cutting position, thereby preventing return to the intermediate cutting position.
16. The cable stripping tool according to claim 15, wherein the locking element comprises a releasable ratchet arrangement including a first set of teeth connected to the body section and a second set of teeth mounted to the blade actuator, one of the first and second set of teeth being movable to release the ratchet arrangement.
Description
BRIEF DESCRIPTION OF THE SEVERAL VIEWS OF THE DRAWING
[0041] Other characteristics and advantages of the invention shall appear upon reading the detailed description and the appended drawings, in which:
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DETAILED DESCRIPTION OF THE INVENTION
[0057] Referring to
[0058] In accordance with installation guidelines, the cables 6, 8, 14 and 16 are each provided with a first cable marker 22a-d including an indicia 24a-d indicative of the electrical state of the cable, with a L indicating the live cables and a N indicating the neutral cables. The outgoing live 14 and neutral 16 cables both include a second cable marker 26c and 26d respectively having indicia 28c and 28d matching the indicia of the corresponding first cable marker 22. The presence of two cable markers indicates to the installer the outgoing cables.
[0059] As shown in
[0060] As shown in
[0061] The stepped reduction in diameter between the first channel section 36 and the third channel section 40 creates a first abutment shoulder 42. Similarly, the stepped reduction in diameter between the third channel section 40 and the second channel section 38 defines a second abutment shoulder 44. When a cable having a 25 mm diameter sheath is inserted into the first marker 22 it is accommodated within the first channel section 36 with the outer walls of the sheath 30 closely engaging the walls of the first channel section 36. One or more projections at 46 may extend radially into the first channel section 36 which locally deform the sheath 30 to key and rotationally lock the first marker 22 on to the cable. The axial end surface of the sheath 30 when fully inserted abuts the first abutment shoulder 42, which acts as a stop and prevents further axial travel of the sheath 30 through the marker 22, as shown in
[0062] The first marker 22 is also able to receive a 16 mm diameter cable. In this arrangement the cable is received within the third channel section 42 without engagement with the walls of the first channel section 34. Again the third channel section 40 may include one or more radially extended projections 46 to rotationally restrain the cable. The end surface of the sheath 30 of the cable engages the abutment surface 42 and in the same way as described above prevents axial travel of the sheath 30 past the abutment shoulder 44 while permitting the inner cables 32 to extend through the second opening 40.
[0063] As shown in
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[0065] When the cable is fully received within the second marker 26 the resilient arms 54 in their expanded configuration provide a returning force which clamps the arms against the cable. The compressed distal ends 58 are angled in the flexed form such that the end surfaces angle inwardly in the insertion direction A with the cable being inserted a sufficient distance in to the marker 26 that part of the inner surface of the distal sections 56 engage the rear side of the cable relative to the insertion direction A urging the cable into the second marker 26, with the barbs 68 assisting to prevent retraction of the cable. A locating arm 70 is provided within the marker 26 proximate the bridging section 52. The locating arm 70 has a curved profile and is secured at its base to one of the arms 54 and extends across the void within the marker 26 towards the other arm 54 with the end of the locating arm 70 being spaced from the other arm 54. The locating arm 70 is flexible and able to flex in the insertion direction A towards the bridging section 52. The locating arm 70 provides a stop for smaller 16 mm cables. If such smaller cables were to be inserted all the way into the marker such that they abutted the bridge 52 then they would not be adequately gripped by the distal ends 58 of the arms 54. The locating arm 70 limits insertion of the cable and provides a returning biasing force against the cable in a direction opposing the insertion direction A, thereby clamping the cable between the distal ends 58 and the arm 54 and the locating arm 70. Where a large 25 mm cable is inserted into the marker 26 the locating arm is able to flex rearwardly towards the bridging section 52 to accommodate the larger cable.
[0066] As shown in
[0067] As shown in
[0068] In an alternative embodiment shown in
[0069] An alternative cable marker/connector 122 is shown in
[0070] When a stepped cable having a 25 mm outer diameter sheath is inserted into the marker 122 it is accommodated within the first channel section 136 with the outer walls of the sheath 30 closely engaging the D4 diameter wall of the first channel section 136. A projection at 147 extends radially into the first channel section 136 which locally deforms the sheath 130 to key and rotationally lock the marker 122 on to the cable. The first abutment shoulder 135 abuts against the first abutment shoulder 142 of the marker 122. The exposed length 127 of the inner sheath having a reduced diameter D2 equal to the diameter D5 of the second channel section 138 extends into the second channel section 138. The length of the second channel section 138 is equal to the length L2-L1 of the exposed inner sheath section 127 such that the second abutment shoulder 137 seats against and abuts abutment shoulder 144 of the marker 122. Similarly where a 16 mm tie is used the first abutment shoulder 135 of the cable 129 seats on the third abutment shoulder 146 of the maker 122 and the second abutment shoulder 137 seats on the final abutment shoulder 148. The length of the fourth channel 145 is equal to the length of the exposed inner sheath section 127. It is important that the cable 129 is accurately stripped at length locations LI and L2 and that at these points the cable 129 is cut to the diameters D1 and D2 respectively. To avoid human error and lack of consistent reproducibility,
[0071] The circular blades 162 are rotationally mounted to the blade actuator 166 with their rotational axis 176 being arranged parallel to the longitudinal axis of the channel 154 and such that they are arranged transversely to the longitudinal axis 164. The blades 162 are concentric and coaxial. The first blade 178 has a first diameter D9 and the second blade 180 has a second diameter Di0 that is greater than the diameter D9. The difference in diameters D9 and Di0 is selected such that the blade edge of the second blade 180 is spaced radially outwards from the blade edge of the first blade 178 a distance equal to Di-D2, being the radial thickness of the second abutment shoulder 137 which also corresponds to the thickness of the inner sheath 133 of the cable 129. The blades 178, 180 are axially spaced by a distance equal to the length of the exposed inner sheath section 127.
[0072] Rotation of the blade actuator 166 about the wall 172 of the aperture 160 pivots the blades 162 along an arcuate path towards and away from the channel 154 in a plane transverse to the longitudinal axis 164 of the channel 154. When a cable 129 is received in the channel 154 the outer surface of the cable 129 engages the inner edges of the ribs 170 which are sized such that their inner edges define an inner diameter to the channel 154 that is equal to the relevant cable diameter. The blade actuator 166 is configured to pivot the blades 162 to a first cutting position as shown in
[0073] In the fully retracted position of the blade actuator 166 the second blade 180 is located at a radial distance from the longitudinal axis greater than or equal to the inner diameter of the channel 154 as defined by the inner edges of the ribs 170 such that a cable 129 may be inserted into the channel 154 with interference with the blades 162. A stop member 182 extends radially outwards from the wall 172. The stop member 182 is received with a channel 184 in the body of the blade actuator 166 defined by a recess in the circular inner wall that surrounds the wall 172. The end walls 186 and 188 of the recess engage with the stop member 182 to limit rotation of the blade actuator 166. The spacing and angular location the end walls 186 and 188 define the stop positions of the fully cutting position and the fully retracted position respectively. As can be seen in the section view of
[0074] Referring to
[0075] The teeth 194, 196 and 202,204 include corresponding sloping camming surfaces on their leading edges such that as the first tooth 196 contacts the first tooth 202 of the latch the teeth cooperate to slide the latch 200 towards the release position to allow the tooth 196 to move past the tooth 202. Once past the biased latch returns to the locked position and the tooth 196 is latched against tooth 202 in a ratchet manner. The latch 200 and the locking arm 192 are arranged such that this first engagement corresponds to an intermediate rotational position of the actuator 166 in which the blades extend partially into the channel 154 but not to the full cutting position.
[0076] With the blades 162 penetrating the sheath 130 of the cable 129 to a partial cutting depth the user grips the cable 129 with a first hand and the inner surface of the wall 172 of the handle 158 with their finger and uses the handle 158 to rotate the tool 150 around the cable 129. The longitudinal axis of the channel 154 defined the rotational axis of the tool 150. Rotation of the tool 150 around the cable 129 causes the blades 162 to effect a fully circumferential cut, meaning a cut that extends a full 360 degrees around the cable. The partial extension of the blades 162 to the intermediate cutting position makes this fits cutting operation easier with deformation of the cable being limited during the cut. The trigger is then further depressed moving the locking arm to a second locking position corresponding to the full cutting position of the blades 162, in which the first locking tooth 196 of the locking arm moves into engagement with the second locking tooth 204 of the latch, and the second locking tooth 194 of the locking arm 192 moves into engagement with the first latch tooth 202. The rotational cutting process is then repeated, with the tool preferably being rotated several rotations to effect a complete cut. Following the second cutting operation the cable may be retracted from the channel 154. Retracting the cable 129 with the blades 162 still in the full cutting position causes the blades 162 to axially retain the cut portions of the sheath within the channel such that the cable is retracted in a fully stripped state. The slide switch 206 of the latch 200 is then operated to return the actuator 166 to the retracted position. This also acts to release the stripped sections of the sheath.
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