US3824775A

US3824775A - Method of and apparatus for stranding elongate material

Info

Publication number: US3824775A
Authority: US
Inventors: N Birch
Original assignee: National Standard Co
Current assignee: National Standard Co
Priority date: 1971-08-26
Filing date: 1972-08-24
Publication date: 1974-07-23
Anticipated expiration: 1991-07-23
Also published as: GB1352361A; CA960096A; FR2151381A5; IT964986B; BE788041A; ZA725736B; NL7211552A; AU4591372A; DE2241826A1

Abstract

In a machine for stranding elongate material for example metallic wire, comprising a first support means for receiving spools of the material to be stranded, a rotary twisting component, and a second support means for receiving a take-up spool for the stranded product, said rotary twisting component is disposed within an enclosure, means is provided for creating at least a partial vacuum within the enclosure, and sealing means is mounted in a wall of said enclosure through which the stranded product leaving the rotary twisting component is led to the takeup spool. Said first support means may also be disposed within said enclosure.

Description

[451 July 23,1974

[ METHOD OF AND APPARATUS FOR STRANDING ELONGATE MATERIAL [75] Inventor: Norman John Birch, Wordsley,

England [73] Assignee: National-Standard Company Limited, Worcestershire, England [22] Filed: Aug. 24, 1972 [21] Appl. No.: 283,558

[30] Foreign Application Priority Data 9/l963 France 57/58.52

119,457 9/1958 U.S.S.R 57/58.52

Primary ExaminerDonald E. Watkins Attorney, Agent, or Firm-Johnson, Dienne, Emrich, Verbeck & Wagner [5 7 ABSTRACT In a machine for stranding elongate material for example metallic wire, comprising a first support means for receiving spools of the material to be stranded, a rotary twisting component, and a second support means for receiving a take-up spool for the stranded product, said rotary twisting component is disposed within an enclosure, means is provided for creating at least a partial vacuum within the enclosure, and sealing means is mounted in a wall of said enclosure through which the stranded product leaving the rotary twisting component is led to the take-up spool. Said first support means may also be disposed within said enclosure.

4 Claims, 3 Drawing Figures PATENTED JUL 2 31974 PATENIEUJUL23IHT4 SHEET 2 OF 2 NQI ain.

ww gwm 5 Q@ NW METHOD OF AND APPARATUS FOR STRANDING ELONGATE MATERIAL This invention relates to apparatus for stranding elongate material.

A strand is made by twisting together a plurality of lengths of filamentary material and a rope is made by twisting together a plurality of strands. Various kinds of machines are known for producing strands, for example high speed tubular stranding machines, bunchers and twisters, and the twisting together of strands to form a rope may also be performed in similar machines.

In order to simplify the ensuing description the word stranding will be usedto include both the forming of strands from filamentary material and theforming of ropes from strands, and a machine for making strands from filamentary material or rope from strands will be referred to as a stranding machine.

The apparatus of this invention have been devised mainly for employment in the stranding of metallic wire material and the remainder of this specification will be confined to a description of the stranding of such material. It is to be understood, however, that the apparatus of the invention is applicable to the stranding of other filamentary material, for example natural fibrous material and fibrous material made from synthetic plastics material.

In the stranding of wire the speed at which the stranding machine operates is limited by a number of factors, including the effect of centrifugal force on certain components of the machine, the effect of centrifugal force on the product, the design of the machine bearings, the generation of heat in components of the machineand in the product, and the noise generated by operation of the machine.

The present invention is concerned primarily with reducing the amount of heat and noise generated in the stranding of wire in a stranding machine. At the present time, steps taken to try to reduce the heat generated have the result of accentuating the noise, and vice versa. A great deal of the noise is generated aerodynamically by components of the machine and the product travelling through the air at high velocity. Considerable power is also consumed in driving components of the machine and the product through the air and the air pumping losses cause machine components to heat up.

The noise problem can be dealt with by completely enclosing the machine with a well-fitting guard which is lined with sound-absorbing material. Unfortunately, such a completely enclosing guard prevents air flow through the machine and, with the same air circulating around the inside the-guard all the time, the machine components are quickly heated up to an unacceptable level. If vents are provided in the guard to allow the escape of some of the air flow through the machine, noise is also allowed to escape.

One way in which the twin problems of heat and noise generation could possibly be avoided in the operation of a stranding machine would be to enclose the machine in a sound-insulating guard and to provide the guard with means for supplying air to and extracting air from the guard in a closed circulation system. This closed circulating system would itself have to be soundproofed and would need to comprise means to cool the air extracted from the guard before returning it to the latter. Such a system would be both space-consuming and expensive.

The present invention seeks to overcome in a simple way the problems of heat and noise generation in the operation of a stranding machine.

According to the invention a machine for stranding elongate material comprises an enclosure, first support means, a plurality of supply spools of elongate material to be stranded supported by the first support means, a rotary twisting component disposed within the enclosure for twisting the elongate material from the supply spools into a strand, second support means disposed outwardly of the enclosure, a take-up spool supported by said second support means for receiving the strand, means associated with the enclosure for creating at least a partial vacuum within the enclosure, and sealing means mounted in a wall of the enclosure through which the strand passes from the rotary twisting component to the take-up spool.

When employing the machine of the invention the volume of noise transmitted from the twisting component of the stranding machine and the moving wire to a person outside the enclosure is considerably reduced by the existence of sub-atmospheric pressure within the enclosure. Consequently, it is not necessary for the walls of the enclosure to be efiiciently sound-proofed. The wastage of power consumed in circulating air insidethe enclosure is also greatly reduced. This in turn leads to a decrease in the risk of the machine parts becoming overheated.

In the case of a tubular wire stranding machine in accordance with the invention, said first support means may also be located in said enclosure.

With double bunchers the rotary twisting component can either rotate around said first or second support means. In a double bunchers in accordance with this invention, those sections of the machine which carry the wire around the first support means are housed in said enclosure.

Since leakage of air into the enclosure from the surroundings will inevitably take place in a stranding machine in accordance with the invention, adequate pumping capacity will have to be provided to maintain the partial vacuum in said enclosure when the machine is in operation.

If lubricated members of the stranding machine, for example shaft bearings, are located within said enclosure, steps would have to be taken to prevent removal of lubricant through the air-extracting equipment. This could be done by hermetically sealing the lubricated members from the interior of said enclosure. This difficulty can, however, be avoided in some cases by mounting items such as shaft bearings externally of said enclosure. Simple air seals would then be provided where the shafts enter the enclosure.

If overheating of members of the stranding machine which are located within said housing is a problem, then cooling of these members may have to be resorted to, for example by providing them with water or oil cooling systems.

The invention will now be described in greater detail, by way of example, with reference to the accompanying drawings, in which FIG. 1 is a schematic sectional side view of a first embodiment of a stranding machine of the double buncher type in accordance with the invention,

FIG. 2 is a view similar to FIG. 1 of a tubular wire stranding machine, and

FIG. 3 is a sectional view of a sealing means employed in apparatus in accordance with the invention for leading wire from an evacuated closed space.

The machine shown in FIG. 1 comprises a frame 1 provided with aligned bearings 2, 3 in which a rotary twisting component consisting of two rotary heads 4, 5 is mounted. The heads 4, 5 comprise

shafts

6, 7 respectively, which are rotated in synchronism with one another by endless flexible drive members 8, 9, respectively, from a common drive shaft 10.

Mounted between the two heads 4, 5 and prevented from rotating therewith by suitable counterweights is a first support means, generally designated by the numeral 11. The latter comprises a housing 12 provided at opposite sides with aligned

stub shafts

13, 14 which are received in

bearings

15, 16, respectively, mounted in the heads 4, 5, the axes of the bearings l5, 16 being aligned with the axes of the bearings 2, 3. Four spools 17 of wire are rotatably mounted on shafts 18 within the housing 12, the shafts 18 being disposed at right angles to the axes of the

bearings

15, 16.

The stub shaft has a central axial hole 19 therethrough which serves as a stranding die for four wires 20 led therethrough from the spools 17. After passing through the die 19 the stranded wires pass around a pulley 21 rotatably mounted on a shaft 22 in the head 4, around

pulleys

23 and 24 rotatably mounted at the peripheral edges of

flanges

25 and 26, respectively, forming parts of the heads 4 and 5, respectively, around a pulley 27 rotatably mounted on a shaft 28 in the head 5, and then through an axial hole 29 in the head 5. The stranded wire is drawn from the hole 29 by a capstan 30 and is laid on to a spool 30a by a traversing mechanism 31, the spool 30a being mounted in a second support means 32.

The items so far described are standard components of a wire stranding machine of a double buncher type. In operation of the machine, rotation of the shaft 10 causes synchronised rotation of the heads 4, 5 around the housing 1 1 to effect stranding of the wires 20 drawn 3 from the spools 17 by the take-up spool 30a.

In the machine shown in FIG. 1, the twisting component consisting of the heads 4, 5 and the first support means 11 are enclosed in a cylindrical air-tight casing 33, the casing axis being in substantial alignment with the axes of the bearings 2, 3. The casing 33 has a pcripheral wall 34 and

end walls

35, 36, the latter being provided with centrally disposed holes'37, 38 for passage therethrough of the

shafts

6 and 7 of the heads 4 and 5. Annular air-

tight seals

39 and 40 are mounted in the

holes

37, 38, respectively, these seals providing an air-tight seal between the

stationary end walls

35, 36 of the casing 33 and the rotary heads 4, 5. The peripheral wall 34 of the casing is made in at least two parts hinged together by means of hinges 41 to afford easy access to the parts of the stranding machine located within the casing 33.

An outlet opening 42 is provided in the casing 33, which opening is connectible to a vacuum pump 43 by a conduit 44. When the pump 43 is set in motion the interior of the casing 33 is partially evacuated. Entry of air into the casing through the hole 29 can be prevented to a large degree by suitably dimensioning the hole 29. For example the hole 29 may have a diameter of from 0.05 to 0.12 mm greater than the diameter of the stranded wire passing therethrough. Depending on the wire diameter, a suitable length for the hole 29 is from 7.5 to 15.0 cms. The hole 29 may be provided in a separate sleeve 45 (see FIG. 3) which is mounted in the shaft 7 of the head 5. A range of different sleeves 45 suitable for different wire diameters can then be supplied with the machine.

By partially evacuating the casing 33, the noise emitted by the rotary twisting component 4, 5 and by the wires 20 in moving from the spools 17 to the hole 29 is to a large extent cut off from an operative'supervising the machine. There is no need for the casing 33 to be made of a sound-insulating material. Instead, it can be made of a sound material having good heat-conducting properties, for example sheet metal, so that heat radiated from the moving components within the casing 33 can be transmitted through the casing and thus prevent overheating of the components within the casing.

FIG. 2 shows a tubular wire stranding machine hav ing two

sections

50, 51 each provided with a conventional tube 52 within which is a first support means in the form of cradles 53 carrying spools 54 of wire. The tubes 52 are'driven in synchronism with one another by a comon drive shaft 55 which is itself driven by an electric motor 56. Wires 57 from the spools 54 pass through a stranding die 58 and thence to a take-up device 59 for the stranded wire, the device 59 including a take-up spool 60. The parts so far described are standard items of a conventional tubular wire stranding machine.

Around each of the tubes 52 there is arranged a stationary cylindrical casing 61, for example of sheet metal. The ends of the casing 61 are sealed in an airtight manner to frame members 62 of the machine in which the tubes 52 are rotatably supported. Each casing 61 has an outlet opening 63 which is connectible to a vacuum pump (not shown) so that the interior of the casing can be partially evacuated when the machine is in operation. As in the case of the machine of FIG. 1, each of the casings 61 is preferably made in a plurality of parts, suitably hinged together, in order to afford easy access to the components within the casing.

In both of the machines described above with reference to the drawings, there will inevitably be a certain leakage of air into the partially'evacuated casings of the machines. This is of no consequence provided that adequate pumping capacity is provided to maintain evacuation of the casing at a suitable level.

What is claimed is:

l. A machine for stranding elongate material comprising, an enclosure, first support means, a plurality of supply spools of elongate material to be stranded supported by said first support means, a rotary twisting component disposedwithin said enclosure for twisting the elongate material fromsaid supply spools into a strand, second support means disposed outwardly of the enclosure, a take-up spool supported by said second support means for receiving said strand, means associated with said enclosure for creating at least a partial vacuum within said enclosure, and sealing means mounted in a wall of said enclosure through which said strand passes from the rotary twisting component to said take-up spool.

2. A machine as claimed in claim 1, in which said first support means is also disposed within said enclosure.

3. A machine as claimed in claim 1, in which said enclosure is a casing made of sheet metal.

4. A machine as claimed in claim 3, in which said casing is made of a plurality of parts hinged together.

Claims

1. A machine for stranding elongate material comprising, an enclosure, first support means, a plurality of supply spools of elongate material to be stranded supported by said first support means, a rotary twisting component disposed within said enclosure for twisting the elongate material from said supply spools into a strand, second support means disposed outwardly of the enclosure, a take-up spool supported by said second support means for receiving said strand, means associated with said enclosure for creating at least a partial vacuum within said enclosure, and sealing means mounted in a wall of said enclosure through which said strand passes from the rotary twisting component to said take-up spool.