WO2005046015A1

WO2005046015A1 - Cable stripping device

Info

Publication number: WO2005046015A1
Application number: PCT/IB2004/003020
Authority: WO
Inventors: Jiri Stepan
Original assignee: Schleuniger Holding Ag
Priority date: 2003-11-07
Filing date: 2004-09-16
Publication date: 2005-05-19
Also published as: CH697076A5; CN1902797B; JP4606417B2; CN1902797A; KR101103207B1; JP2007511198A; TWI359545B; KR20070017299A; TW200531390A

Abstract

The invention essentially concerns a cable stripping device having a centring device with a number of centring jaws (8) which exceeds preferably by at least two a number of blade-holders with blades (23, 25, 26) located in the immediate proximity of the centring jaws, acting independently therefrom in the radial direction and rotatable independently therefrom about a rotational axis. The number and arrangement of the centring jaws (8) in relation to the blade-holders with blades (23, 25, 26) is such that when the blades carry out a rotary cutting movement, a phase shift occurs in the interaction between the blade-holders with blades (23, 25, 26) and the centring jaws (8). This has an attenuating or compensating effect on the vibrations produced in the cable to be stripped, thus enhancing cutting precision. Special configurations of the blades and centring jaws, as well as of their computer-assisted control, are also disclosed.

Description

stripping device

The invention relates to a stripping device with a centering device comprising a number of centering jaws, which exceeds the number of knife holders with knives which are located in the immediate vicinity and act radially independently thereof and which can be rotated independently about an axis of rotation by at least two.

Such an arrangement is published in patent application WO-A-9813907 in FIGS. 21 and 28 to 32. There is a "rotary box" as

Part of an endless cable processing device described. This is used in continuous cable processing machines to facilitate stripping processes for coaxial cables.

In this known prior art (cf. WO-A-9813907, FIGS. 21 and 28 to 32), a hollow jaw shaft is attached over a rigid sleeve, which torque of a gearwheel is applied to a spiral flange, which is engaged by pins with four centering jaws , transmits. The centering jaws are guided in a jaw guide, which causes the centering jaws to be pushed together or apart. Coaxial to

The jaw shaft has two knives in a knife guide. A spindle drives a wedge along. A cylinder pin locks the wedges. Rotation of a second gear causes the wedges to move axially. This movement acts on the knife holder with knives in the closing or opening direction.

The use of the arrangement of four centering jaws and two knife holders with knives has been tried and tested and the achievable cutting quality is very good. A comparable arrangement has also been in use in another design by the applicant "MP 8015" for many years. Since the known design no longer achieves the desired precision with a lower limit on the cable diameter can, but has been intensively striving for an improvement in cutting precision. In extensive investigations, the inventors discovered that, contrary to the previous opinion, the centering jaws are able to center the cable, but with particularly thin cables there is a tendency for the knives in their knife holders to counteract the centering by quasi closing the cable through the two knives an oval is deformed and has the tendency to sidestep the knives (oval effect). In addition, extensive observations and considerations revealed that, surprisingly, vibration occurs in the cutting area of the cable, which results from the rhythm that results from the recurring, simultaneous superposition of the knife and centering jaws in one flight.

Based on these new and inventive findings, the new and inventive task now was to improve the known device in such a way that the precision is increased and to remove the disadvantageous effects of the known arrangements which were recognized for the first time.

The first inventive step is to coordinate the direction, number and arrangement of the centering jaws in relation to the knife holder with knives in such a way that, during the rotary cutting, a phase shift in the interaction of the encounter of the knife holders with knives and centering jaws is brought about, which occurs when a vibration builds up in the cables to be stripped have a damping or compensating effect and therefore increase the cutting precision.

The inventor also recognized for the first time:

Due to the clamping of a cable with an inherently elastic outer sheath, the centering, in contrast to the two knife arrangements, leads to a polygonal deformation of the cable cross-section (polygon effect). This was originally round and becomes quasi polygonal due to this deformation, with the "corners" between the Form centering jaws. This design also changes the cutting forces which rotating knife holders with knives find when they cut a cable along the circumference. The change in cutting forces, on the other hand, leads to a pulsating and rhythmic loading of the entire structure or parts thereof, starting with the knives via the holder, storage, centering jaws and back via the cable back into the knife holder with knives. According to this new discovery by the inventor, this pulse-like load particularly affects thin cables and correspondingly small knife holders with knives, centering jaws and the surrounding mechanical structures. It must be taken into account that the device has only finite rigidity. However, the quality of the stripping cut also depends on the ripple and frequency as well as the amplitude of the cutting force.

A first countermeasure would be to increase the number of support points in the centering. This would reduce the amplitude of the pulse load between the support points, but at the expense of more extensive mechanics or with more components.

However, the inventor also found that there are directions of force in which cyclical amplitude fluctuations occur due to the out-of-roundness of a cable layer (polygon effect) and the amplitudes in the mechanical structure can overlap unfavorably and can lead to geometric deviations in the cut (lack of precision). It is therefore a further inventive object to find a structure in which amplitudes of undulating force changes on the knife holders cannot be amplified or rocked with knives, but rather can have a compensating effect. Force pulses should not occur abruptly if possible, but should be able to swell in to a maximum and then to a minimum. This is achieved according to the invention in that the plurality of tools, in particular knife holders with knives, successively instead of simultaneously having cable regions with higher ones Process cutting forces as they occur due to the polygon effect. At the same time, regenerative effects in the vibration range should be avoided, in which even the out-of-roundness of the previous cut further excites the vibration. A non-integer ratio between the number of centering jaws and knife holder with knives is suitable according to the invention in order to shift the vibrations of the individual knife holders with knives in phase relationship to one another and thus to eliminate reinforcing overlaps.

All of these new and inventive tasks are solved by the new arrangements according to the invention of the relationship between centering jaws and knife holder with knives, five centering jaws to three knife holders with knives being recognized as the economically optimal ratio. A ratio of four to three already leads to an improvement, but the force fluctuations with regard to the

Polygon effect larger than with five centering jaws. A ratio of six to three can bring a regenerative effect and a ratio of seven to three is already very complex with regard to the control of the centering jaws. A ratio of e.g. Seven to four all the more.

The preferred limitation of the knife holder with knives to three also goes hand in hand with the fact that several knife holders with knives increase the risk with regard to the risk of tolerance-related deviations in the knife geometry that the cuts of the several knives are not exactly in the same plane, so that the precision of the cutting surface could suffer qualitative losses for this reason, which is independent of the above.

The inventor also recognized that compared to conventional 2 knife holders with knives (oval effect), the cable with three knives is additionally centered by the cutting forces and the roundness of the cable is less influenced by the cutting forces. The absolute Deformations of an oval are namely larger according to the findings of the invention than with a triangular-like deformation. These additional effects also increase the quality of work of the device according to the invention (polygon effect beats oval effect).

According to the invention, the superimpositions are best avoided with broken conditions. The number of centering jaws should not be an integer multiple of the number of knife holders with knives. Six to three means three knives in the same phase to the cable ripple, i.e. amplification of the disturbing force pulses. Five to four brings a sequential sequence of individual force pulses, so little overlap. Six to four is not an integer; but there are always two knives in phase, two exactly in opposite phase. Overall, the ratio is therefore too regular and therefore two force pulses arise at the same time, which should preferably be avoided according to the invention, since mutual compensation is simply not sufficient.

Further developments of the invention are given in the figures, the description of the figures and in the dependent claims.

The list of reference symbols is part of the disclosure.

The invention is explained in more detail symbolically and by way of example using figures.

The figures are described coherently and comprehensively. The same reference symbols mean the same components, reference symbols with different indices indicate functionally identical or similar components.

It show Fig.1 - A perspective drawing of a structure according to the invention in an assembled embodiment;

Fig.2 - An exploded perspective view of the structure according to the invention according to Fig.1;

Fig.3 - A sectional drawing of the structure according to the invention according to Fig.1;

Fig.4 - A schematic representation of the angles between adjacent centering jaws and between adjacent knife holders with knives;

Fig. 5 - Three curve diagrams for case 1 (prior art);

Fig. 6 - Four curve diagrams for case 2 (preferred embodiment of the invention) and

Fig.7 - A perspective drawing of a special embodiment of the structure according to the invention in an assembled version.

FIGS. 1-3 describe the structure according to the invention, the novel "micro coax box" which, compared to the known "rotary box", allows the stripping of much thinner cables without errors and with high precision.

The first pulley 4 arranged over a rigid main shaft 5 is controlled by a toothed belt which is driven by a motor. The first pulley 4 transmits the desired or set torque to the camshaft shaft 24 / first spiral flange 41 via an adjustable slip clutch, which is via pins are in engagement with the centering jaws 8. Since the centering jaws 8 are guided in a centering flange 7, rotation of the camshaft shaft 24 / first spiral flange 41 causes the centering jaws 8 to be pushed together or apart. The desired torque or the force of the centering jaws is achieved by means of a preload of a spring 27 by adjusting one first mother 2 reached.

The braking force decides the contact pressure of the centering jaws 8 on the outside of a cable jacket. The centering jaws 8 are L-shaped in section, so that they enable a very compact design and still offer a wide centering or clamping surface for cables to be stripped. Their ends protrude right next to the knives. However, due to their L-shape, they offer an exemption for any tours.

A second spiral flange 11, which carries a second pulley 6, is arranged on two ball bearings 1 coaxially to the first pulley 4. The second spiral flange 11 also carries a head body 10 by means of ball bearings 37. The second pulley 6 and head body 10 are both driven independently of one another and optionally differentiated by means of toothed belts. Knife holders with knives 23, 25, 26 are mounted on a knife flange 12, which is firmly connected to the head body 10, so as to be radially movable. By means of the cylindrical pins 32, which are firmly connected to the knife holders with knives 23, 25, 26 and are in engagement with the second spiral flange 1, the relative movement between the second pulley 6 and the head body 10 causes the knife holders with knives 23, 25 to be pushed together or apart , 26 and thus acts on them in the closing or opening direction. However, other closing or opening devices for knife holders with knives known to the person skilled in the art are also within the scope of the invention. The

Relative movement arises from a speed difference when driving the second pulley 6 or the head body 10. FIG. 4 shows the uniformity of the angles as they occur between adjacent knife holders with knives 23, 25, 26 and between adjacent centering jaws 8, as well as the unequal angle sizes that exist between knife holders with knives 23, 25, 26 and centering jaws 8 can result.

5 and 6 represent curve diagrams relating to the prior art and to the preferred embodiment of the invention, or case 1 an examination with four centering jaws and two knife jaws with knives and case 2 an examination with five centering jaws and three knife jaws with knives, the radius deviations (Δr) with fewer support points are smaller in the first case than in the second. Therefore, the changes in cutting force (ΔF; a curve for each knife) are smaller in the second case. The scaling of the ordinate (level) is arbitrary, while the abscissa (angle α) comprises a full rotation (= 2π). The temporal course of the cutting force is cyclical and has been represented as a sine function for the sake of simplicity, without this affecting the general previous and subsequent statements. When considering vibration superpositions, the assumption is made analogously that symmetrical relationships apply within the structure at the location under consideration and that the vibrations can be added by linear superposition. In places where this is not exactly true, the same statements apply qualitatively, v. a. regarding the amplification of vibrations in phase.

The curves can be interpreted in detail as follows:

Case 1 :

In the first curve, a double radius deviation four, in each case between two adjacent centering jaws (a r _max) and in each case gives 360 ° times to each of four adjacent centering jaws (r a _m i _n). The equation is:

In the second curve, the same 360 ° shows which force profile is created on the first knife. Where the radius increases, the resistance and thus the force also increases. Therefore, this curve runs synchronously with the first curve.

The equation is as follows: ΔFι (α): = qι ^' sin (α ^' n-ι) The third curve shows the force profile on the second knife over the same 360 °. Since this runs with the first knife offset by 180 °, it has the same force change properties as the first knife and at the same time. The pulses of the first and second knife add up, so that the amplitude in the summation curve swings up to twice the value of the second and third curve. The equation is: ΔF ₂ (α): = ΔFι (α)

Case 2:

In the first curve there is a double radius deviation five times over 360 °, namely between two adjacent centering jaws (one r _m aχ) and in each case adjacent to each of the four centering jaws (one r _m j _n ). Since the r-deviation inevitably becomes smaller with more points of attack of a centering system, the amplitude of the curve is smaller than with the first curve in case 1. With an infinite number of centering jaws, the r-deviation would be zero. The equation is:

In the second curve, the same 360 ° shows which force profile is created on the first knife. Where the radius increases, the resistance and thus the force also increases. Therefore, this curve runs synchronously with the first curve. Since the r-deviation is smaller than in the first case, the force development difference is also smaller than in the first case. The equation is:

In the third curve, the same 360 ° shows which force profile is created on the second knife. Since this is offset by 120 ° the first knife runs, it has a 120 ° shifted force change properties, like the first knife and at the same time. The force change curve is therefore offset from that from the second curve. The equation is: ΔF ₂ (α): = q ₂ sin [(α + (2π / 3)) n ₂ ] In the fourth curve everything is analogous to the third curve. The pulses of the first, second and third knives add up to zero, so that the amplitude in the summation curve is set to zero, so not only a quantitative reduction but also a qualitative reduction of force pulses occurs. So we cut with the frequency of the first curve from the second part, but we have no forces overlapping by the

Knife. The same effect would also occur with four centering jaws and three knife jaws, although the amplitude of Δr would be larger, as in the first curve of case one. The equation is: ΔF ₃ (α): = q ₂ ^' sin [(α + (4π / 3)) n ₂ ]

7 illustrates how a cable end can be inserted radially to its axis from the side into the working area of the knife holder with knives (23, 25, 25).

At its core, the invention relates in one embodiment to a stripping device with a centering device comprising a number of centering jaws (8), which have the number of knife holders with knives (23 , 25, 26), preferably by at least two, the number and arrangement of the centering jaws (8) with respect to the knife holder

Knives (23, 25, 25) during rotary cutting cause a phase shift in the interplay of the knife holders meeting with knives (23, 25, 26) and centering jaws (8), which has a damping or compensating effect on vibration build-up in the cable to be stripped and thus Cutting precision is increased. Special Refinements with regard to the knives and centering jaws as well as with regard to the computer-controlled control are also given.

The invention can thus be optimally arranged and operated as an independent stripping device or as part of a continuous cable processing system.

LIST OF REFERENCE NUMBERS

1 ball bearing

2 First mother

3 brake flange

4 First pulley

5 main shaft

6 Second pulley

7 centering flange

8 centering jaw

9 centering cover

10 head bodies

11 Second spiral flange

12 knife flange

13 knife cover

14 guide tube

15 handle

16 Second mother

17 First spacer ring

18 Second spacer ring

19 brass spigot (prevents damage by the grub screw)

20 brass pins (prevents damage by the grub screw)

21 brass spigot (prevents damage by the grub screw)

22 bearings

23 First knife holder with knife

24 camshaft

25 Second knife holder with knife

26 Third knife holder with knife

27 spring

28 grub screw (for locking the second nut 16) Set screw (for locking the brake flange 3) Set screw (for locking the pulley 6)

straight pin

Cylinder pin Countersunk screw Countersunk screw Ball bearing

Plain bearing thrust washer First spiral flange

Claims

claims

1 . Stripping device with a centering device comprising a number of centering jaws (8), which exceeds the number of knife holders with knives (23, 25, 26) that are located in the immediate vicinity and act radially independently of them and independently of them about an axis of rotation, preferably between adjacent centering jaws (8) are formed with uniform first angles and further preferably with uniform second angles between adjacent knife holders with knives (23, 25, 26), characterized in that the number of centering jaws (8) and / or the number of knife holders with knives (23, 25, 26), is odd and that the first angles are not a whole multiple of the second angles.

2. Stripping device with a centering device comprising a number of centering jaws (8), which exceeds the number of knife holders with knives (23, 25, 26) that are located in the immediate vicinity and act radially independently of them, and independently of these and can rotate about an axis of rotation characterized in that the number and arrangement of the centering jaws (8) with respect to the knife holder with knives (23, 25, 26) during rotary cutting a phase shift in the interaction of the encounter of the knife holders with knives (23, 25, 26) and centering jaws (8 ) causes a damping or compensating effect in the case of a vibration build-up in the cable to be stripped, thus increasing the cutting precision.

3. Stripping device according to one of the preceding claims, characterized in that the number of centering jaws (8) that of the knife holder with knives (23, 25, 26) by at least two exceeds and / or that their number is not divisible by a common divisor.

4. Stripping device according to one of the preceding claims, characterized in that, in particular in the idle state, at most one centering jaw (8) with a knife holder with knife (23, 25, 26) is aligned in the axial direction of a cable.

5. Stripping device according to one of the preceding claims, characterized in that, in particular in the idle state, at most a single centering jaw (8) with a knife holder with knife (23, 25, 26) is aligned in the radial direction of a cable, when viewed in the plane of the drawing if the axis of the cable or the axis of rotation of the knife holder with knives is perpendicular to the plane of the drawing.

6. Stripping device according to one of the preceding claims, characterized in that the centering jaws (8) are designed to be rigid.

7. Stripping device according to one of the preceding claims, characterized in that the centering jaws (8) about the axis of rotation - preferably against the direction of rotation of the knife holder with knives (23, 25, 26) - are designed to be rotatable.

8. Stripping device according to one of the preceding claims, characterized in that the knife holder with knives (23, 25, 26) are arranged in the operating position between the centering device and the end of the cable to be stripped.

9. Stripping device according to one of the preceding claims, characterized in that a specific position of the or the knife holder (s) with knife (s) (23, 25, 26) can be fixed and the knife holder with knives (23, 25, 26) as well as the centering jaws (8) and any other second centering, clamping or clamping devices as well If necessary, any further stripping stations are designed such that a cable end can be inserted radially to its axis from the side into the working area of the knife holder with knives (23, 25, 26).

10. Stripping device according to one of the preceding claims, characterized in that the centering jaws (8) or knife holder with knives (23, 25, 26) lie in one plane, and that each diameter of a cable has a different point on the knife edge, or another line is assigned on the centering surface or can be brought into tangential contact with the cable.

11. Stripping device according to one of the preceding claims, characterized in that the centering jaws (8) each have recesses for sliding along the line of contact of an adjacent centering jaw (8).

12. Stripping device according to one of the preceding claims, characterized in that the knife holder with knives (23, 25, 26) each have recesses for sliding along the line of contact of a respectively adjacent knife holder with knife (23, 25, 26).

13. Stripping device according to one of the preceding claims, characterized in that there is no common divider for the number of centering jaws (8) and that of the knife holder with knives (23, 25, 26).

14. Stripping device according to one of the preceding claims, characterized in that the knife holder with knives (23, 25, 26) can be driven radially by first actuating means in order to actuate the knife holder with knives (23, 25, 26) such that at least two different cable layers can be cut or two different diameters can be approached, electronic means being provided to enter and store the at least two different radial positions and to control at least the first actuating means.

15. Stripping device according to one of the preceding claims, characterized in that the stripping device comprises a knife flange (12) which carries the knife holder with knives (23, 25, 26) in order to cut in at least two cable layers, second actuating means being provided to the To move the knife flange (12) axially relative to the cable in at least two different preselectable axial positions with respect to the cable to remove the at least two cable layers and electronic means to store the at least two different preselectable axial positions and at least the second Control actuating means.