GB2261397A

GB2261397A - Cutting wound coils

Info

Publication number: GB2261397A
Application number: GB9123298A
Authority: GB
Inventors: Joseph Anthony Mcwilliams; Ali Paybarah
Original assignee: Zortech International Ltd
Current assignee: Zortech International Ltd
Priority date: 1991-11-02
Filing date: 1991-11-02
Publication date: 1993-05-19
Anticipated expiration: 2011-11-02
Also published as: EP0541256A3; EP0541256A2; GB9123298D0; DE69203209D1; EP0541256B1; GB2261397B; DE69203209T2

Description

1-,3 ',., ') 7 1 IMPROVEMENTS IN OR RELATING TO CUTTING WOUND COILS The

present invention relates to a method and an apparatus for cutting wound coils, and more particularly is concerned with a method and an apparatus for cutting the wire of a wound coil against a support.

It is known to cut the wire of a wound coil against a support through which the coil passes, for example so as to cut the coil into predetermined lengths. This is accomplished by means of a cutting blade, the cutting blade being movable towards and away from the support such that, as the cutting blade moves towards the support, the blade is inserted between adjacent turns of the coil, and cuts the wire as the coi 1 rotates. The disadvantage of this known method is that the blade does not reliably become inserted between adjacent turns of the coil, particularly when the coil is rotating at high speed, and this can lead to deformation of the ends of the coils. There is therefore a need to improve the method of cutting the wire so as to minimise any deformation of the ends of the coils, particularly when the coil is rotating at high speed.

It is an object of the present invention to provide a method and apparatus for cutting W ound coils in which the wire is cut in a manner which reduces the likelihood of the ends of the coils being deformed.

2 According to one aspect of the present invention there is provided a method for cutting wound coils, comprising the steps of:

providing a wound coi-1 which is rotating about its axis; providing a support against which the coil is to be cut; moving a rotatable cutting blade incorporating an arcuate cutting edge towards the rotating coil and the support such that the cutting blade rotates against the wound coil, becomes inserted between adjacent turns of the wound coil and cuts the wire forming the coil against the support; and moving the cutting blade away from the coil.

The cutting blade may be freely rotatable. edge may be circular.

The cutting The method may include the step of limiting movement of the rotating coil in a direction perpendicular to the axis thereof during the cutting of the wire.

According to another aspect of the present invention there is provided apparatus for cutting wound coils comprising a support for supporting wire in the form of a wound coil, and a cutting blade including an arcuate cutting edge, the cutting blade being movable towards and away from the 1 3 support so as to cut the wire comprising the wound coil, wherein the cutting blade is rotatably mounted in a support member so as to be rotatable with the wound coil.

The cutting blade may be circular and may be provided with a circular cutting edge around the periphery thereof.

The support may comprise a coil retaining member for limiting movement of the coil as a result of movement of the cutting blade towards and away from the coil.

The apparatus may include a lifting pin movable within the coil retaining member towards and away from the coil for limiting movement of the coil relative to the coil retaini-ng member.

The cutting blade may be freely rotatable in the support member.

The apparatus may include a roller for limiting movement of the cutting edge of the cutting blade in the axial direction of the coil.

For a better understanding of the present invention and to show more clearly how it may be carried into effect reference will now be made, by way of example, to the accompanying drawing which shows one embodiment of an 4 apparatus according to the present inventi.on for cutting wound coils.

The figure shows a wound coil 1 of wire 2, the coil 1 passing through an aperture 3 in a coil retaining member in the form of a coil retaining block 4. The wire 2 may be a resistance heating wire comprising, for example, an ironchromium-aluminium alloy. Also provided within the coil retaining block 4 is a coil lifting pin 5 for intermittently raising the coil 1 against the upper surface of the aperture 3 so as to limit movement of the coil relative to the coil retaining block and to move the coil towards a cutting blade 6 which is positioned at that side of the coil retaining block 4 from which the wound coil emerges so as to facilitate indexing the turns of the coil with the cutting blade 6.

Cutting blade 6 is circular in shape with an arcuate cutting edge in the form of a circular cutting edge around the periphery thereof and is provided with a central aperture by means of which the blade 6 is rotatably mounted in a cutting blade support member 7. The cutting blade may have a diameter of about 60 mm. The support member 7 is movable towards and away from the coil 1 so as to cut the wire 2 against the base of the aperture 3. A roller 8 serves to restrain movement of the cutting blade 6 in the axial direction of the coil 1.

1.

In use of the apparatus, the required length of the coils is determined, for example in dependence on the number of turns required and thus the number of revolutions of the mandrel l.' Each time the required length of coil has been wound and passed through the aperture in the coil retaining block 4, the coil lifting pin 5 is raised by means not shown, for example by pneumatic or hydraulic means or by an electrical relay, so as to raise the coil against the upper surface of the aperture 3 in the coil retaining block 4 and to facilitate indexing the cutting blade 6 with the turns of the coil 1. The cutting blade 6, because it is freely rotatable, rotates with the coil reduces relative movement between the coil 1 and facilitates the inserted between adjacent turns of member 7 is moved by means not This mutual rotation the cutting blade 6 and cutting blade becoming the coil as the support shown, for example by pneumatic or hydraulic means or by an electrical relay, towards the base of the aperture 3 so as to cut the wire.

We have found that the use of a rotatable cutting blade in place of a conventional non-rotatable cutting blade considerably reduces the likelihood of the ends of the coils being deformed, results in reduced wear of the cutting blade, and also facilitates increased rotational speeds of the mandrel and of the coil, up to 10,000 r.p.m. or more, and thus increased productivity, compared with the usual rotational speeds of approximately 2,000 to 4,000 r.p.m.

6

Claims

CLAIMS of:

A method for cutting wound coils, comprising the steps providing a wound coil which is rotating about its axis; providing a support against which the coil is to be cut; moving a rotatable cutting blade incorporating an arcuate cutting edge towards the rotating coil and the support such that the cutting blade rotates against the wound coil, becomes inserted between adjacent turns of the wound coil and cuts the wire forming the coil against the support; and moving the cutting blade away from the coil.
2. A method according to claim blade is freely rotatable.
3. A method according to claim edge is circular.

wherein the cutting wherein the cutting
4. A method according to any preceding claim, and including the step of limiting movement of the rotating coil in a direction perpendicular to the axis thereof during the cutting of the wire.

11 7
5. A method for cutting wound coils substantially as hereinbefore described with reference to the accompanying drawi ng.
6. Apparatus for cutting wound coils comprising a support for supporting wire in the form of a wound coil, and a cutting blade including an arcuate cutting edge, the cutting blade being movable towards and away from the support so as to cut the wire comprising the wound coil, wherein the cutting blade is rotatably mounted in a support member so as to be rotatable with the wound coil.
7. Apparatus as claimed in claim 6, wherein the cutting blade is circular and is provided with a circular cutting edge around the periphery thereof.
8. Apparatus as claimed in claim 6 or 7, wherein the support comprises a coil retaining member for limiting movement of the coil as a result of movement of the cutting blade towards and away from the coil.
9. Apparatus as claimed in claim 8 and including a lifting pin movable within the coil retaining member towards and away from the coil for limiting movement of the coil relative to the coil retaining member.
10. Apparatus as claimed in any one of claims 6 to 9, wherein the cutting blade is freely rotatable in the support member.
11. Apparatus as claimed in any one of claims 6 to 10 and including a roller for limiting movement of the cutting edge of the cutting blade in the axial direction of the coil.
12. Apparatus for cutting wound coils substantially as hereinbefore described with reference to, and as shown in, the accompanying drawing.

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