CUTTING DEVICE FOR STRIPPING LAYERS OF CABLES AND SIMILAR PRODUCTS

Abstract: A cutting device for stripping layers of cables and similar products, comprising a handle (12), a frame (10) fixed in the handle (12), knives (14, 16) regulatable and adjustable in the frame (10) for stripping an outer layer by longitudinal, transverse and helical cutting and a guiding element on a rod (26) arranged in the frame, the guiding element having a base plate (32) arranged turnable and adjustable around an axle transverse to the longitudinal axle of the rod (26) and two discs (34) for longitudinal supporting the product with layers to be cut at the base plate (32). The cuttung device comprises according to the invention a further knife (18) for stripping an inner layer along a spiral path, arranged turnable in the frame (10) oppositely to the rod (26), a fork (42) connected to the base plate (32) and two rollers (38) arranged parallel to the discs (34) on the fork (42) and means for adjusting the distance between the knife (18) and the base plate (32). The device is capable of stripping different layers meeting different requirements.

Description: CUTTING DEVICE POR STRIPPING LAYERS OP CABLES AND SIMILAR PRODUCTS The invention relates to a cutting device for stripping layers of cables and similar products comprisin a plurality of knives for stripping different layers. The device according to the invention can be used mainly during preparing a power cable before mounting. As it is known, the power cables comprise in general an outer mantle, a plurality of thin copper wires under the mantle, a hard semiconductor layer under the copper wires and an insulating layer covering current conductors under thensmiconductor layer. When connecting two sections of power cables for preparing a power line the cable ends should be placed in a special connecting element. Por plaβing it is required to strip the mantle and partly the semiconductor layer wherein a transient part with gradually diminishing diameter has to be cut in the semiconductor layer between the stripped and non-stripped parts thereof. The st r ipped part should be characterised with high surface quality in order to ensure the possibility of connecting the element and the layer with absence of air bubbles. The copper wires don^t have to be stripped, it serves for localizing the defects of the cable. The πaotle can be stripped either after longitudinal cutting when its material is soft, or after transverse and/or helical cutting when it is made of hard material. According to the prior art several solutions and a plurality of apparata are known for stripping and cutting the outer insulating layer(s) of cables. These can be classified into different groups, thus, there are devices cutting longitudinally, transverse¬ ly and helically; the majority are hand-tools. Several versions of said solutions are specified in different publications, e.g. in the DE-OS 2139 196 or US-PS 3 881249, these having been developed as some version according to the aforementioned groups. A more progressive solution is also known, e.g. from the WO 83/01530 published on 14th April, 1983, which enables the performance of cutting in all of the three mentioned directions with the aid of a hand-tool. This device comprises a knife which can be turned in a frame with a grip and can be regulated by displacement in the longitudinal direction for annular and helical stripping, while on the outer surface of the frame there is an encased knife extending for longitudinal cutting. By using said knife the aforementioned operations can be faultlessly and easily performed in a short time after a short training period. However, to promote economical production, in course of developing cable techuics, newer products has found application which contain one or more hard semiconductor layers beneath the insulating layer. Por cutting and processing the sane, cutting to size, forming and surfaces at a determined angle and for matching to the connecting element, extremely complicated and expensive devices were experimentally developed. However, none of them have met the requiremen s. The aim of the invention is to eliminate the deficiencies of the prior art and to develop a cutting hand-tool, which in addition to the removal of the outer insulating layer of cables and similar products within strict tolerances, is well suited for cutting and matching processes. Accordingly, the invention relates to a cutting device for stripping the layers of cables nd similar products, comprising a handle, a frame fixed in the handle, knives regulatable and adjustable in the frame for stripping an outer layer by longitudinal, transverse and helical cutting and a guiding element on a rod arranged in the frame, having a base plate arranged turnable and adjustable around an axle transverse to the longitudinal axle of the rod and two discs for longitudinal supporting the product with layers to be cut at the base latentfurther knife for stripping an inner layer (e.g. the semiconductor layer) along a spiral path, arranged turnable in the frame oppositely to the rod, a fork, connected to the bas plate and two rollers arranged parallel to the discs on the fork and means for adjusting the distance between the knife and the base plate. It is a very advantageous embodiment, wherein the knife is arranged in a turnable disc equipped with means for longitudinal adjusting the position of the kiive and/or the rod is connected to a regulator for al ei±ig the distance of the . base plate from and the anglemposition thereof relatively to the frame. It is proposed for better tooling the semi¬ conductor layer fork be connected to the base plate turnable around an axle parallel with the axle of the rollers and be equipped with an adjusting element supported on an arched end thereof, and/or the knife have an arched cutting edge. The main advantage of the solution according to the invention lies in that by using a single simple manual cutting device, in addition to the removal of the outer insulating layer(s) it is rendered suitable also for cutting hard semiconductor layer(s) and it is possible to prepare the matching part of the product with properly dimensioned and bevelled surface as required by the connecting element. Further features of the invention will become apparent from the enclosed description of a prefeisd, though not exclusive, embodiment thereof, illustrated by way of example and not of limitation in the accompanying drawings, which show in Figure 1 a side-view of the cutting tool, partly in view, partly in section, Figure 2 a rear elevation of the cutting tool with the knife on the side face, and in Figure 3 one end of the base plate. As becomes clear from figure 1, device according to the invention, i.e. the so-called cable-stripping pliers have on one end of a frame 10 a handle 12. In the frame 10 a knife 14 can be lowered corresponding to the thickness of a hard insulating layer for transverse cutting and can be turned at an optional angle for helical cutting if required. On the outer surface of the frame 10 a knife 16 is lowered into the frame 10 for cutting a soft insulating layer in longitudinal direction and it is provided with fixing means for the cutting process. On one side of the frame 10, in a disc 24 - which can be turned by means of a pivot 20 (Fig. 2) - a knife 18 with a knife-holder 22 is fixed in a longitudinally adjustable OMPI manner. The cone angle of the knife 18 is formed in accordance with the requirements set to the different cables with layers to be cut. By turning the disc 24 by 90° removal of the outer insulating layer can be performed in the usual way. A rod 26 in the bore of the handle 12 is formed with a key-groove 28, while for turning at an optional angle, a rod regulator 30 is provided with known mechanical elements. As a a consequence, a base plate 32 fixed onto the end of the rod 26 guides the cable thus clamped according to the requirements of the cutting process. On the base plate 32 discs 34 are mounted on arms 36 and can be brought into two extreme positions. On the other end of the base plate 32 there ia a fork 42 with rollers 38 arranged parallel to the discs 34. On the end of the fork 42 there is an arched path 50 wherein a screw 44 can be slipped for the accurate adjustment of the rollers 38 around a pivot 40. The vertical positioning of the rod 26 is possible by means of a spring and a fixing element; both for stripping the outer insulating layer of the cable and internal cutting, the cable can be led to the knife in a most advantageous manner. Essentially, similarly to the removal of the outer insulating layer, the cutting tool according to the invention is rotated with the hand on the cable for performing the cutting process and for matching to the cable elements. The device according to the invention solves the tasks set according to requirements, its applicability was proved in practice, manipulation can be easily learned.

Claims: CLAIMS: 1. Cutting device for stripping layers of cables and similar products, comprising a handle, a frame fixed in the handle, knives regulatable and ; adjustable in .the frame for stripping an outer layer by longitudinal, transverse and helical cutting and guiding element on a rod arranged in the frame, the guiding element having a base plate arranged turnable and adjustable around an axle transverse to the longitudinal axle of the rod and two discs for long¬ itudinal supporting the product with layers to be cut at the base plate, c h a r a c t e r i s e d i n comprising a further knife (18) for stripping an inner layer along a spiral path, arranged turnable in the frame (10) oppositely to the rod (26), a fork (42) connected to the ba3 plate (32) and two rollers (38) arranged parallel to the discs (38) on the fork (42) and means for adjusting the distance between the knife (18) and the base plate (32). 2. Cutting device according to claim 1, w h e r e i n the knife (18) is arranged in a turnable disc (24) equipped with means for longitudinal adjusting the position of the knife (18). 3. Cutting device according to claim 1 or 2, w h e r e i n the rod (26) is connected to a regulator (30) for altering the distance of the base plate (32) from and the angle position thereof relatively to the frame (10). 4. Cutting device according to any precedent claim, w h e rei n the ' fork (42) is connected to the base plate (32) turnable around an axle parallel with the axle of the rollers (38) and is equipped with an adjusting element supported on an arched end (50) of the fork (42). JREA] O PI ^?NATlθ 5. Cutting device according to any precedent claim, w h e r e i n the knife (38) has an arched cutting edge.

Inventors: SZVETNIK LAJOS, SZVETNIK, LAJOS
Applicants: SZVETNIK LAJOS, SZVETNIK, LAJOS
Application year: 1984
Main classification: H02G1
IPC codes: H02G1