GB2046648A

GB2046648A - Double Block Wire Accumulator

Info

Publication number: GB2046648A
Application number: GB8011257A
Authority: GB
Original assignee: Orion Machinery and Engineering Corp
Current assignee: Orion Machinery and Engineering Corp
Priority date: 1979-04-17
Filing date: 1980-04-03
Publication date: 1980-11-19
Also published as: IT7969427A0; IT1193123B; FR2454344A1

Abstract

A double block wire accumulator (10) has a draw block (12) mounted on the upper end portion of a hollow drive shaft (24). A take-off ring (16) which carries a turn-around pulley (18) is supported above the draw block by another drive shaft (28) which extends co-axially upwardly through the hollow drive shaft. An accumulator block (14) is journalled for free rotation above the take-off ring on a shaft extension (42) mounted on and extending co-axially upwardly from the take-off ring. The draw block is driven in one direction by a main drive motor (56) drivingly connected to the lower end of the hollow drive shaft. Another motor (60) drivingly connected to the lower end of the other drive shaft applies torque in the one direction to the take-off ring. Both motors are remote from the block region. <IMAGE>

Description

SPECIFICATION A Double Block Wire Accumulator, Wire Processing Apparatus Including Such an Accumulator and Wire Processed Thereon Technical Field and Background Art This invention relates in general to wire processing apparatus and deals more particularly with a double block wire accumulator.

A double block wire accumulator is usually used in a progressive wire drawing line which includes a plurality of such accumulators arranged in series to draw wire through a series of dies supported in dieboxes. The accumulators operate to maintain relatively uniform tension on wire being drawn and also function as festoons for storing quantities of wire and paying it off, as required, to prevent a sudden increase in wire tension which may result in wire breakage in the event of a jam at a diebox or the sudden slowdown of an associated draw block. A typical double accumulator includes a draw block driven in one direction, an accumulator block supported for co-axial free rotation relative to the draw block, and a transfer or take-off ring which carries a turn-around pulley and is supported between the draw block and the accumulator block.Wire wound in the one direction on the draw block passes over tiie iurrl-arourlü pulley and is vvuund in the opposite direction on the accumulator block. Such an accumulator further includes means for applying torque to the take-off ring in the direction of draw block rotation. When desired wire tension is maintained, torque applied to the take-off ring is counter-balanced by tension in the wire which causes the take-off ring to remain in a substantially fixed position. The take-off ring responds to an increase or decrease in wire tension by rotating in one or the opposite direction, as required, to restore desired tension, In one type of accumulator the take-off ring is frictionally coupled to the draw block so that rotation of the draw blockapplies torque to the ring in the direction of draw block rotation.Such frictional coupling wastes power, since some of the power used to drive the draw block is lost in overcoming the substantially constant frictional braking action applied to the draw block by the take-off ring. Further, the friction material used in the coupling requires periodic replacement which results in costly machine down-time. In another accumulator, of so-called frictionless type, torque is applied directly to the take-off ring by a separate motor. In a prior proposal the motor is located in the region of the blocks and may be drivingiy connected to the take-off ring by a drive belt engaged within a peripheral groove in the ring. This arrangement limits accessibility to the blocks and is troublesome, particularly during treading-up operations.

It is an object of the present invention to provide a double block accumulator which alleviates the aforementioned problems.

Statement of Invention and Advantages According to the present invention there is provided a double block wire accumulator comprising a draw block and an accumulator block supported above the draw block with a take-off ring supported between said blocks and carrying a turn-around pulley, and a shaft assembly supporting the draw block, the accumulator block and the take-off ring for rotation about a common axis, the shaft assembly comprising first and second drive shafts supported for co-axial rotation about the common axis with the draw block mounted for rotation with the first drive shaft and drive means drivingly connected to the first drive shaft below the draw block to rotate the draw block in one direction about the common axis, and the take-off ring mounted for rotation with the second drive shaft with torque applying means connected to the second drive shaft below the draw block to apply torque to the take-off ring in said one direction.

Further, according to the present invention, there is provided wire processing apparatus including one or more accumulators as described in the immediately preceding paragraph, and wire when processed on such apparatus.

It is an advantage of the accumulator of the present invention that the torque applying means is connected to the second drive shaft below the draw block so that the torque applying means is conveniently located out of the block regioh. The torque applying means preferably comprises a motor and control means adapted to adjust the torque applied to the take-off ring by the motor.

The motor is conveniently an air motor.

Advantageously in the accumulator of the present invention, the first drive shaft comprises a hollow shaft and the second drive shaft extends through the first drive shaft. Accordingly, the draw block and the drive means may be connected to upper and lower portions, respectively, of the first drive shaft, and the take-off ring and the torque applying means may be connected to upper and lower portions, respectively, of the second drive shaft. The shaft assembly conveniently includes a shaft extension extending upwardly relative to the draw block, on which the accumulator block is journalled for rotation.

Figures in the Drawings One embodiment of a double block wire accumulator in accordance with the present invention will now be described by way of example only, with reference to the accompanying drawings, in which: Figure 1 is a side elevational view of the accumulator, shown in a wire drawing line; Figure 2 is a plan view of the accumulator shown in Figure 1, and Figure 3 is an elevational view of the accumulator of Figure 1 shown partially in section taken along the line 3-3 of Figure 2.

Detailed Description of the Drawings Turning now to the drawings, a double block wire accumulator embodying the present invention and indicated generally by the reference numeral 10 in Figure 1, is particularly adapted for use with other accumulators of like kind arranged in series in a progressive wire drawing line. The illustrated accumulator 10 generally comprises a draw block 12, for drawing wire W through a diebox D1 and an accumulator block 14, for accumulating wire and paying it off to the draw block on another accumulator (not shown) which forms a part of the drawing line and which pulls wire from the accumulator block 14 and draws it through another diebox D2.The accumulator 10 also includes a take-off ring 1 6 which carries a turn-around pulley 1 8 and which controls accumulation of wire on the blocks 12 and 14 to maintain tension on the wire W as it is payed off the block 14, as will be hereinafter further discussed.

Considering the apparatus in further detail and referring particularly to Figure 3, the accumulator 10 has a frame or housing 20 and a vertically extending drive shaft assembly indicated generally at 22. The shaft assembly includes a first, hollow drive shaft 24, journalled in upper and lower bearings 26 carried by the frame, and a second drive shaft 28, which extends co-axially through the hollow drive shaft 24. The shaft 28 has a diametrically enlarged flange 30 near its upper end and is supported by a thrust bearing 32 ffiSi)f32d be.vveerl till líaTlge 3û ar,d the upper end of the drive shaft 24.

The generally cylindrical draw block 12 is keyed to the hollow drive shaft 24 and is retained in vertically spaced relation to the upper bearing 26 by a tubular spacer 34 received on the shaft 24 and disposed between the lower end of the draw block hub and the inner race on the upper bearing 26. The latter inner race rests on an annular shoulder formed on the drive shaft 24. A retaining nut 36 threaded on to the upper end of the shaft 24 bears against the upper surface of the draw block 12 and retains it on the drive shaft 24.

The take-off ring 1 6 is driven by the drive shaft 28 and has a central hub 38 connected to the flange 30. A central aperture 40 formed in the take-off ring hub receives an upwardly projecting end portion of the shaft 28 to ensure co-axial alignment between the take-off ring and the latter shaft. The turn-around pulley or sheave 1 8 is carried by a shaft 39 which projects substantially tangentially from the take-off ring 1 6 and is supported with its groove in generally tangential alignment with the outer peripheral surfaces of the blocks 12 and 14, as best shown in Figure 2.

A vertical extension shaft 42 forms part of the shaft assembly and is supported on and secured to the hub 38 in co-axial alignment with the shaft 28. The shaft 42 has a diametrically enlarged flange 44 near its lower end which rests on the upper surface of the hub 38, and the lower end portion of the extension shaft 42 projects into the bore 40 to ensure proper co-axial alignment of the shaft 42 with the remainder of the shaft assembly 22.

The accumulator block 14 is generally cylindrical and journalled on the shaft extension 42 by bearings 46. The outer races of the bearings 46 are seated on annular shoulders formed in a stepped bore 47 which extends through the hub portion of the accumulator block 14. Tubular spacers 48 and 50 received on the extension shaft 42 maintain the inner races of the bearings 46 in vertically spaced relation to each other and to the annular flange 44.

The accumulator block 14 is coupled to the take-off ring 1 6 by a one-way dr sprag clutch 52.

The outer race of the clutch 52 rests upon the flange 44 and is fastened to it by bolts (one shown) which also fasten the flanges 30 and 44 to the hub 38. The inner race of the clutch 52 is secured to the hub portion of the accumulator block 14. The spray clutch 52 is arranged to permit the accumulator block 14 to turn freely at all times in a clockwise direction relative to the take-off ring 1 6 but to prevent the accumulator block from turning in a counter-clockwise direction relative to the take-off ring when the accumulator block is in a fixed position relative to the take-off ring. The sprag clutch 52 also prevents the accumulator block from running ahead of the take-off ring when the latter ring is turning in a counter-clockwise direction, as viewed from above.

A main drive motor 56 drives the draw block 12 through a worm gear set which includes a pinion 58 keyed or otherwise secured to the lower end portion of the hollow drive shaft 24, as best shown in Figure 3. Another motor 60 mounted on the frame 20 and drivingly connected to the shaft 28 provides adjustable means for applying torque to the latter shaft. The illustrated motor 60 preferably comprises an air motor connected to the shaft 28 through a belt and pulley drive indicated generally at 62. A suitable pneumatic control 64 is provided for varying torque applied to the shaft 28 by the air motor 60.

The accumulator 10 is preferably threaded up with a relatively large number of convolutions of wire wound on each of the blocks 12 and 14, the number of convolutions of wire on the block 12 being generally equal to the number of convolutions on the block 1 4. However, for convenience in illustrating the operation of the apparatus, the accumulator 10 is shown in Figure 1 with only a few convolutions of wire W wound on each block.

The main drive motor 56 drives the draw block 12 in counter-clockwise direction, as viewed from above and as shown in Figure 2, to draw wire W through the diebox D,. Wire is wound in a counter-clockwise direction on the block 12, passes over the turn-around pulley 18, and is wound in an opposite or clockwise direction on the accumulator block 14, as shown in Figure 2.

The wire travels from the accumulator block through the diebox D2 and may pass over a suitable arrangement of sheaves (not shown) to the draw block of the next accumulator in the wire drawing line which pulls the wire from the accumulator block 14 and draws it through the diebox D2. The pneumatic control 64 is adjusted to cause the motor 60 to apply counter-clockwise torque to and through the shaft 28 to the take-off ring 16, as viewed from above. The applied torque is proportional to tension in the wire W.

Under normal operating conditions, when wire W is wound on the draw block 12 at substantially the same speed at which it is stripped from the accumulator block 14, the torque drive motor 60 remains in a virtually stalled condition. When the latter condition exists there is no appreciable rotational movement of the take-off ring, since the predetermined tension in the wire W being stripped from the accumulator block 14 is maintained. Torque applied to the wire W at the turn-around pulley is substantially counterbalanced by tension in the wire as it leaves the accumulator block If a slow-down occurs in the apparatus ahead of the accumulator 10, a slack condition occurs in the wire as it leaves the accumulator with a resulting reduction in wire tension.The take-off ring 1 6 responds to this condition by rotating in counter-clockwise direction in response to torque applied by the motor 60. This counter-clockwise movement of the take-off ring, as viewed from above, causes wire to accumulate on both the draw block 12 and the accumulator block 14. The take-off ring 1 R continues to rotate clockwise direction until a balanced condition is attained and the predetermined tension in the wire leaving the accumulator block is restored.

If tension in the wire W being pulled from the accumulator 10 should increase beyond the predetermined tension, due to increase in the speed of the pulling apparatus ahead of the accumulator 10 or decrease in the speed of the draw block 12, the take-off ring 1 6 will rotate in clockwise direction, as viewed from above, to simultaneously reduce the amount of accumulated wire on both the draw block 12 and the accumulator block 14. The take-off ring will continue to rotate in clockwise direction until a balanced condition is attained wherein torque applied by the motor 60 is counter-balanced by tension in the wire being pulled from the accumulator 10.

As previously noted, the accumulator block 14 is at all times free to rotate in clockwise direction to allow wire to be pulled from the accumulator 10. However, in the event that the wire being pulled from the accumulator breaks the take-off ring will respond by rotating in counter-clockwise direction. The spray clutch 52 functions to prevent the accumulator block 14 from running ahead of the take-off ring in counter-clockwise direction or in a direction counter to the direction in which the convolutions of wire are wound thereon. Thus, the sprag clutch prevents loss of control of wire wound on the accumulator block in the event of wire breakage.

Claims

1. A double block wire accumulator comprising a draw block and an accumulator block supported above the draw block with a take-off ring supported between said blocks and carrying a turn-around pulley, and a shaft assembly supporting the draw block, the accumulator block and the take-off ring for rotation about a common axis, the shaft assembly comprising first and second drive shafts supported for co-axial rotation about the common axis with the draw block mounted for rotation with the first drive shaft and drive means drivingly connected to the first drive shaft below the draw block to rotate the draw block in one direction about the common axis, and the take-off ring mounted for rotation with the second drive shaft with torque applying means connected to the second drive shaft below the draw block to apply torque to the take-off ring in said one direction.

2. A double block wire accumulator as claimed in claim 1 in which the first drive shaft comprises a hollow shaft and the second drive shaft extends through the first drive shaft.

3. A double block wire accumulator as claimed in claim 2 in which the draw block and the drive means are connected to upper and lower portions, respectively, of the first drive shaft, and the take-ofF ring and the torqüe appiyiny meaiìs are connected to upper and lower portions, respectively, of the second drive shaft.

4. A double block wire accumulator as claimed in any one of claims 1 to 3 in which the torque applying means comprises a motor and control means adapted to adjust the torque applied to the take-off ring by the motor.

5. A double block wire accumulator as claimed in claim 4 in which the motor is an air motor.

6. A double block wire accumulator as claimed in any one of the preceding claims in which clutch means is provided to connect the accumulator block to the take-off ring which is adapted to permit free rotation of the accumulator block in a direction opposite to said one direction and to prevent rotation of the accumulator block ahead of the take-off ring in said one direction.

7. A double block wire accumulator as claimed in claim 6 in which the clutch means comprises a sprag clutch having an inner race secured to the accumulator block and an outer race secured to the take-off ring.

8. A double block wire accumulator as claimed in any one of the preceding claims in which the shaft assembly includes a shaft extension extending upwardly relative to the draw block, on which the accumulator block is journalled for rotation.

9. A double block wire accumulator as claimed in claim 8 in which the shaft extension extends upwardly from the take-off ring and is mounted for rotation therewith.

10. A double block wire accumulator substantially as herein described with reference to the accompanying drawings.

11.Wire processing apparatus including one or more accumulators as claimed in any one of the preceding claims.

12. Wire when processed on apparatus as claimed in claim 11.