GB1566611A - Wire annealing apparatus - Google Patents

Description

(54) WIRE ANNEALING APPARATUS (71) I, AUGUSTUS WILLIAM HENRY BANYARD, a British subject of 18a, Western Road, Branksome Park, Poole, Dorset, do hereby declare the invention for which I pray that a patent may be granted to me and the method by which it is to be performed to be particularly described in and by the following statement:- This invention relates to apparatus for continuously annealing wire.

It is known to continuously anneal copper and aluminium wire after it has been drawn and before it has been spooled. It is also known to pass the wire around a pair of sheaves to form one or more loops and to electrically couple an induction heater with the or each loop in order to induce an electric current in the loop(s) which heats the wire to its annealing temperature.

In order to bring about satisfactory annealing of the wire it is essential that, where the loop is closed on one of the sheaves, good electrical and physical contact is made between the ends of the loop and the sheave and usually it is necessary to make good physical contact between the two ends of the loop. If these good physical contacts are not made then there is the chance of sparking occurring between the ends of the loop and/or between the ends of the loop and the sheave. Sparking causes pitting of the surface of the wire.

It is an object of the present invention to provide apparatus in which the possibility of sparking occurring is considerably reduced as compared with the known apparatus referred to briefly heretofore.

According to the present invention, apparatus for continuously annealing wire comprises a bath of cooling liquid, a first sheave at least partially immersed in the liquid, a second sheave, means for guiding the wire to be annealed around the sheaves to form a loop, an electrical induction heater coupled to the loop and means for engaging the wire constituting the ends of the loop to form a good electrical connection therebetween at a position immersed in said cooling liquid, The urging means may comprise a roller rotatable about an axis substantially parallel to the axis of rotation of the sheave and biased towards the sheave.

If the immersed sheave is of electrically conductive material, then the two ends of the loop need not be physically in contact with each other. The loop is closed through the conductive sheave. If however the sheave is of electrically insulating material, then it is essential that the two ends of the loop are urged into physical contact with each other in order to close the loop. Even when the sheave is of electrically conductive material, it may be desirable for the two ends of the loop to be urged into physical contact with each other as well as into contact with the sheave, In order that the invention may be more readily understood it will now be described, by way of example only, with reference to the drawings filed with the provisional specification, in which: Figure 1 is a diagrammatic side elevation of apparatus in accordance with the invention, Figure 2 is an end elevation of the lower end of the apparatus shown in Figure 1, Figure 3 is a plan view from beneath the lower sheave shown in Figure 1, and Figure 4 is a diagrammatic side elevation of part of apparatus according to an alternative embodiment.

Apparatus for continuously annealing metal wire comprises a pair of sheaves, 1,3 arranged one above the other with part of the lowermost sheave 3 immersed in a bath 5 of cooling liquid. The wire to be annealed is passed around a plurality of guide pulleys (not shown) to form a loop 7 extending around the sheaves 1 and 3. The wire con stituting the ends of the loop are arranged below the surface of the liquid in the bath 5. An electric induction heater 9 is coupled with one of the reaches of the loop 7. A roller 11 positioned below the sheave 3 is biased by means not shown towards the periphery of the sheave 3 to urge the ends of the wire into good electrical contact with the periphery of the sheave.

Referring particularly to Figures 2 and 3, in addition to the roller 11 which serves to urge the ends of the loop 7 into contact with the sheave 3, there are a pair of edge discs 13 rotatably mounted on a pair of arms 15. The axes of rotation of the discs 13 are normal to the axis of rotation of the sheave 3 and the roller 11 and the edge discs are biased into engagement with the end portions of the loop 7 by a spring 17 which acts between the arms 15 which are pivoted at the opposite ends from those which carry the discs 13. The bias applied to the edge discs 13 causes them to engage with the ends of the loop and to urge the end portions into engagement with each other.

In use, the wire to be annealed is formed into the loop 7 and the roller 11 urges the end portions of the loop into engagement with the sheave 3 and the edge discs 13 urge the end portions of the loop into engagement with each other. The loop is thus closed and a current induced by the electric induction heater 9 flows around the loop heating the loop to its annealing temperature. The ends of the wire which form the loop come together beneath the surface of the liquid in the bath 5 and this quenches any sparking which might have occurred as the end portions of the loop come into contact and move out of contact with the sheave and each other.

In the arrangement shown in Figures 1, 2 and 3, the sheave 3 and the roller 11 are of cylindrical form but in the embodiment shown in Figure 4 the lower sheave 3' is of diabolo form and the roller 11' is correspondingly shaped so that the two ends of the loop of wire are urged by the walls of the sheave 3' towards the bottom of the hollow of the sheave and the widest portion of the roller 11' applies forces to the ends of the loop urging them into contact with each other and with the sheave 3'. If required edge discs similar to the edge discs 13 shown in Figure 2 may be used to engage the ends of the wire.

In an alternative embodiment, not shown, the sheave which is located partially in the bath 5 consists of two similar parts mounted on the same shaft and each part carries one of the end portions of the loop. The parts of the sheave are formed of electrically conductive material and there are flexible electrical connections between the two parts in order to close the loop. In this arrangement one loop can be displaced about its axis of rotation for a limited extent relative to the other part and the flexible connections enable the electrical connection to be maintained.

WHAT I CLAIM IS: 1. Apparatus for continuously annealing wire comprising a bath of cooling liquid, a first sheave at least partially immersed in the liquid, a second sheave, means for guiding the wire to be annealed around the sheaves to form a loop, an electrical induction heater coupled to the loop and means for engaging the wire constituting the ends of the loop to form a good electrical connection therebetween at a position immersed in said cooling liquid.

2. Apparatus for continuously annealing wire as claimed in claim 1, in which the first sheave is of, electrically conductive material and the wire engaging means serve to urge the wire constituting the ends of the loop into engagement with the first sheave.

3. Apparatus for continuously annealing wire as claimed in claim 2, in which said means comprises a roller positioned beneath the first sheave and urged towards the sheave.- 4. Apparatus for continuously annealing wire as claimed in claim 3, in which the first sheave is of diabolo form and the roller is correspondingly shaped having a greater diameter at its centre than at its ends.

5. Apparatus for continuously annealing wire as claimed in claim 1, in which said engaging means serve to urge the wire constituting the ends of the loop into contact with each other.

6. Apparatus for contiuuously annealing wire as claimed in claim 5, in which the wire engaging means comprises two discs rotatably mounted about axes normal to the axis of rotation of the first sheave and urged towards each other.

7. Apparatus for continuously annealing wire as claimed in any preceding claim, in which the first sheave comprises two cylindrical parts each of electrically conductive material and mounted on a common shaft with each part being displaceable relative to the shaft and the two parts are connected together by flexible electrically conductive connections.

8. Apparatus for continuously annealing wire substantially as hereinbefore described with reference to the drawings filed with the provisional specification.

**WARNING** end of DESC field may overlap start of CLMS **.

Claims (8)

**WARNING** start of CLMS field may overlap end of DESC **. stituting the ends of the loop are arranged below the surface of the liquid in the bath 5. An electric induction heater 9 is coupled with one of the reaches of the loop 7. A roller 11 positioned below the sheave 3 is biased by means not shown towards the periphery of the sheave 3 to urge the ends of the wire into good electrical contact with the periphery of the sheave. Referring particularly to Figures 2 and 3, in addition to the roller 11 which serves to urge the ends of the loop 7 into contact with the sheave 3, there are a pair of edge discs 13 rotatably mounted on a pair of arms 15. The axes of rotation of the discs 13 are normal to the axis of rotation of the sheave 3 and the roller 11 and the edge discs are biased into engagement with the end portions of the loop 7 by a spring 17 which acts between the arms 15 which are pivoted at the opposite ends from those which carry the discs 13. The bias applied to the edge discs 13 causes them to engage with the ends of the loop and to urge the end portions into engagement with each other. In use, the wire to be annealed is formed into the loop 7 and the roller 11 urges the end portions of the loop into engagement with the sheave 3 and the edge discs 13 urge the end portions of the loop into engagement with each other. The loop is thus closed and a current induced by the electric induction heater 9 flows around the loop heating the loop to its annealing temperature. The ends of the wire which form the loop come together beneath the surface of the liquid in the bath 5 and this quenches any sparking which might have occurred as the end portions of the loop come into contact and move out of contact with the sheave and each other. In the arrangement shown in Figures 1, 2 and 3, the sheave 3 and the roller 11 are of cylindrical form but in the embodiment shown in Figure 4 the lower sheave 3' is of diabolo form and the roller 11' is correspondingly shaped so that the two ends of the loop of wire are urged by the walls of the sheave 3' towards the bottom of the hollow of the sheave and the widest portion of the roller 11' applies forces to the ends of the loop urging them into contact with each other and with the sheave 3'. If required edge discs similar to the edge discs 13 shown in Figure 2 may be used to engage the ends of the wire. In an alternative embodiment, not shown, the sheave which is located partially in the bath 5 consists of two similar parts mounted on the same shaft and each part carries one of the end portions of the loop. The parts of the sheave are formed of electrically conductive material and there are flexible electrical connections between the two parts in order to close the loop. In this arrangement one loop can be displaced about its axis of rotation for a limited extent relative to the other part and the flexible connections enable the electrical connection to be maintained. WHAT I CLAIM IS:

1. Apparatus for continuously annealing wire comprising a bath of cooling liquid, a first sheave at least partially immersed in the liquid, a second sheave, means for guiding the wire to be annealed around the sheaves to form a loop, an electrical induction heater coupled to the loop and means for engaging the wire constituting the ends of the loop to form a good electrical connection therebetween at a position immersed in said cooling liquid.

2. Apparatus for continuously annealing wire as claimed in claim 1, in which the first sheave is of, electrically conductive material and the wire engaging means serve to urge the wire constituting the ends of the loop into engagement with the first sheave.

3. Apparatus for continuously annealing wire as claimed in claim 2, in which said means comprises a roller positioned beneath the first sheave and urged towards the sheave.-

4. Apparatus for continuously annealing wire as claimed in claim 3, in which the first sheave is of diabolo form and the roller is correspondingly shaped having a greater diameter at its centre than at its ends.

5. Apparatus for continuously annealing wire as claimed in claim 1, in which said engaging means serve to urge the wire constituting the ends of the loop into contact with each other.

6. Apparatus for contiuuously annealing wire as claimed in claim 5, in which the wire engaging means comprises two discs rotatably mounted about axes normal to the axis of rotation of the first sheave and urged towards each other.

7. Apparatus for continuously annealing wire as claimed in any preceding claim, in which the first sheave comprises two cylindrical parts each of electrically conductive material and mounted on a common shaft with each part being displaceable relative to the shaft and the two parts are connected together by flexible electrically conductive connections.

8. Apparatus for continuously annealing wire substantially as hereinbefore described with reference to the drawings filed with the provisional specification.