US2770867A - Arrangements for carrying out continuous processes on long rigid articles - Google Patents

Description

Nov. 20, 1956 J. A. SPENCER ARRANGEMENTS FOR CARRYING OUT CONTINUOUS PROCESSES ON LONG RIGID ARTICLES 5 Sheets-Sheet 1 Filed Nov. 1'?, 1951 Nov. 20, 1956 J. A. SPENCER ARRANGEMENTS ROR CARRYING OUT CONTINUOUS PROCESSES ON LONG RIGID ARTICLES 5 Sheets-Sheet 2 Filed Nov. 1'7 1951 m. ww

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Si' I (\l (D LA dames rh 111' Spencer M Horneys Nov. 20, l1956 J. A. SPENCER 2,770,867

ARRANGEMENTS FOR CARRYING OUT CONTINUOUS PROCESSES ON LONG RIGID ARTICLES Filed Nov. 17, 1951 5 Sheets-Sheet 5 F/GS o /6 I 2o Inventor Jef/As Hr ur Spencer ttorney Nov. 20, 1956 J. A. SPENCER ARRANGEMENTS FOR 2,770,867 CARRYING OUT CONTINUOUS Y PROCESSES ON LONG RIGID ARTICLES 5 Sheets-Sheet 4 Filed Nov. 17. 1951 I iIll.

l n ventol- James Hr Mw' Jpen der Attorneys Nov. 20, 1956 J. A. SPENCER 2,770,867

ARRANGEMENTS FOR CARRYING OUT CONTINUOUS PROCESSES ON LONG RIGID ARTICLES 5 Sheets-Sheet 5 Filed Nov. 17, 1951 JZ Attorney 5 United States Patent ARRANGEMENTS FOR CARRYING OUT CON- TINUoUs PROCESSES oN LoNG RIGID ARTICLES James Arthur Spencer, Northumberland Heath, Erith, England, assignor to British Insulated Callenders Cables Limited, London, England, a ,British company Application November 17, 1951, Serial No. 256,946

Claims priority, application Great Britain December 1, 1950 s claims. (CI. 29,-33)

This invention concerned with conditions which arise in performing as a continuous process two Ioperations in succession 4on a long suiciently rigid article, for instance a tube, a rod, or some forms of electric cables, wherein each operation involves, or is accompanied by, the fo-rwarding of the article along a line of travel. For instance the article may be fed from a source of supply to one piece of apparatus in which the rst operation is performed, then passed from it to the second apparatus in which another operation is performed andthen be withdrawn from the apparatus. r

Owing particularly to the rigidity of the article under treatment it is important; inl such cases, to secure close co-ordination of the two means for moving forward the article in order tor avoid producing high stress inthe article or interference with the performance of either or both of the two operations. I-t is not an easy matter `to d'o this by simple observations and hand control since the rigidity of the article will prevent they disclosure of the existence of high stress until this becomes excessive and the interference with the performance of the operations may not become obvious until some defect has been produced. i

It is pointed out that the required forwarding speeds on the two pieces of apparatus may not be the same, since one of the operations performed may have the eifect of lengthening the workpiece. This occurs, for instance, where `one of the operations is -a drawing operation.

It is the object of the'present invention to provide automatic means for securing the required co-ordination. In accordancewith the invention one of the forwarding means, with any appropriate associated gear, is mounted on a carriage which is movable through a short dis- .tance in the line of travel of the article against a centralizing force. When this carriage is displaced from the central position in either sense it acts upon control gear which iniiuences the speed of `one yofthe forwarding-means so as to adjust it in the sense required to produce correction of the condition which has caused the displacement. The displacement of the carriageis brought about by the force exerted on it by the rigid article being treated `owing to the fact that it is being forwarded at different or non-coordinated speeds at different poi-nts in the length under treatment. For instance, if the forwarding means of the second operation in order of succession is causing .the article to travel at a speed greater than that correspending to .the speed of the forwarding'apparatus of the first operation, ythere is tension in the article between the two stages of treatment and this pulls the movable carriage away from its central position. This can be corrected by reducing they speedof the second forwarding means or increasing the speed of the iirst forwarding means.

f Locking lmeans for the movable carriage may be pro- (lll y 2,770,867 ,l Patented Nov. 20,1956

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Gear associated with the forwarding means which it is appropriate to mount on the movable carriage with such means, may bev gear which depends for its operation on themaintenanc'eof a denite relationship with the forwarding means, which relationship would be disturbed by any abnormal relative displacement. The operationperformedmay include the forwarding movement as an inherent part for instance in drawing through a die, or the operation mayjbe associated with the forwarding movement for the purpose of a continuous process, for instance in the making of a seamas by welding or soldering.

The movable carriage is preferably supported by suspension, the suspending members, two or more in number, being so formed as to oier sui'lcient transverse restraint to the carriage to avoid the necessity for lateral 'guides with ytheir accompanying friction. The suspendingrv members preferably valso embody or consist of plate or strip springs cooperating to centralize the lcarriage and to permit small displacementsy longitudinally in either sense. Other forms of support may, however, be adopted, for instance a support ,similar to that above mentioned, but standing up from below instead o-f hanging down from above, or a table sliding Vor running on rolls in longitudinal guides with centralizing springs actinglongitudinally in oppositedirections.

One form of the improved apparatus is described hereinafter by way of example `and ywith reference to the accompanying drawing, wherein: v

Figures 1A and lB together represent a View inelevation ofthe completefapparatus;

Figures 2A and 2B are respective plan views of Figures lA'and 1B; 1 l

Figure 3 is an end view of the apparatus as seen in the direction of .the arrow III in Figure 1A;

Figure 4 is a view in elevation of the switch cont-rolling the speed adjustment;y i f v Figure 5 is a view of the arrangement sho-wn in Figure 4, taken on the line V--V and as seenin the direction of the-arrows; and

Figure 6.1's a circuit diagram of the connections to' the speed-controlling arrangements.

The apparatus is arranged to` apply a sheath I of aluminum to a core 2 comprising an insulated cable conductor. The `sheath I is formed from a tlat strip 3 which is progressively folded about the core, the abutting longitudinal edgesbeing weldedy together toforma tube 4 loose on .the core Zand the' tube. being subsequently drawn through a die 5 which" reduces it to 'aftight fitting sheath on the core. The apparatus .is in two distinct portions, namely, the tube-forming device which' comprises the arrangements in Figure lA excluding the die 5, and the drawing down device comprising the die 5 and the haul-olf arrangements shown: in Figure 1B. The'lirst part forms the 'tube 4' fro-m the strip Srwith4 the core 2 inserted as the `tube is formed, and makes the seam; the second part reduces the diameter `ofthe tube. In the course of the reduction of its diameter the length of the tube is correspondingly increased, so that therate of'travel of the nished articleV leaving the die 5 is greater than that of thefstrip and of the-rate ofl seaming in the first part of the apparatus.v i f The `movement of the tube 4 through lthe rst-part of the device is obtainedy by means of a doublet caterpillar haulage 6 electrically driven by an independent motor 7. 'The tube is drawn through the sinking dieS in the second stage by means of a capstan .driven by an'elec'- tric'motor 9`through Va variable speedV gear v'10. 'I'he control ofrspeedis effected yby means of this second drive, the variable gear 10 being'adapted to be automatically adjusted bya `reversible auxiliary motor 11 controlled by switching arrangements described hereinafter.

The tube-forming device is supported on a carriage 12 suspended so as to be movable within pre-determined limits in the direction ofvmovernent of the strip 3 through the machine.` The line of travel of the strip 3 from the commencement of `its formation into the'tube 4 to the contact between the finished cable I withy the capstan l8 is4 a straight line. The distance between the delivery end of the caterpillar haulage 6 and the sinking die 5 is comparatively short and in this short space the workpiece has the form of a comparatively rigid seamed tube 4 which is a loose tit on the cable body 2 within it. It is in this space that the tube 4 may be subjected to forces of tension or compression as a result of relative variation in the haul-off speeds in the twoparts of the machine. These forces are transmitted from the fixed sinking die 5 to the movable carriage 12, thelatter being displaced in one direction or the other as a result. The rigidity of the tube 4 prevents the existence of undesirable tensile and compressive stresses from being observed until these stresses have reached values at which defects may arise, consequently manual control of the speed is extremely difficult if not impossible.

The carriage 12 comprises a long narrow horizontal frame, substantially rectangular as seen in plan, and consisting of two side members 13, 13 and a number of cross pieces 14. The forward portion of the frame is at a lower level than the rearward portion in order to accommodate the caterpillar haulage 6. The carriage 12 is suspended at cach end `and in a portal formed by two vertical pillars 15, 15 and a horizontal cross bar 16 at the top. In this portal is disposed a cross braced rectangular frame 17 conveniently formed of tubular members and constituting a link between two flat springs 18, 18 attached to the girder 16 and two similar flat springs 19, 19 attached to the back of the carriage 12. Each at spring 18 or 19 is in the form of a plate having its plane disposed transversally to the direction of movement of the tubeforming strip 3. Each of the upper springs 18 is anchored in a bracket 20 by two bolts 21, 21 the bracket 20 being bolted to the cross piece 16. `Each of the lower springs 19 is firmly attached to a vertical face 22at the back of the carriage by two bolts 23, 23. Each spring is rigidly fastened to the link `17 by two bolts 24, 24. The breadth of the at springs 18 and 19, the rigid construction of the link 17 and the rigid attachment of the springs 18, 19 to the carriage 12, to the upper cross piece 16 and to the link 17 are such that the carriage 12 is restrained more strongly against lateral movement than against longitudinal movement. At the same time the springs 18, 19 oier some resistance to the latter movement.

The following apparatus is mounted on the carriage 12. At the rearward end brackets dependent from the carriage support a reel 26 carrying the strip 3 from which the tube 4 is to be formed. A set of three rolls 27 is adapted to receive the strip 3 passing upwards from the reel 26 to straighten it and set its position vertically on the carriage. From the straightening rolls the strip is passed between upper and lower forming rollers 28, 29, the lower 2S of which is grooved so that in its passage between them the strip is bent transversally into a U- shape, as indicated in Figure 3, the lower portion of its section being substantially semi-circular and the two sides extending upwards and outwards from this. The next apparatus carried by the carriage is a pair of guide rollers 30 freely rotatable about vertical axes and adapted to receive the U-shape strip between `them from the forming rollers 28, 29. The strip 3 then passes through `a circular die 31 which completes the bending of the strip into the circular form. Beyond the circular die 31 is mounted an arc welding torch 32 in co-operation with a pair of grooved pinching rollers 33, 33 rotatable on vertical axes and adapted `to hold. the abutting edges of the tube in close contact during welding. Beyond the Welding posil tion the tube 4 passes through'a self-centering guide 34. The insulated conductor is taken from any convenient source (not shown in the drawings) mounted independently of the carriage 12 and is directed into the groove (35 in Figure 2A) formed by the U-shape strip as it passes from the grooving rolls 28, 29 to the guide rolls 30. Between the grooving and guide rolls there is arranged a set of guides for the core 2, these guides being mounted on an independent ixed support 36 extending upwards between the sides ofthe carriage 12. The guides consist of two freely rotatable horizontal rollers 37, 38, and between them 'a pair of freely rotatable vertical rollers 39. The `core is adapted to pass over the first horizontal roller 38, between the two vertical rollers 39, 39 and under the second horizontal roller 37.

The caterpillar haulage 6 comprises two endless belts 40, 40 each mounted in a `carriage 41 supported in a frame 42. The carriersI are attached by linkage to a hand wheel 43 whereby they may be moved towards and away from one another for the purpose of threading the leading end of the tube 4 between them. The caterpillars 40 are driven through gearing 44 from the motor 7 mounted on top of the frame 42. After leaving the caterpillar haulage 6 the pipe 4 passes into the sinking die 5, being lubricated by means of a suitable lubricating device 45. With the exception of the set of guides 37, 38, and 39 for the core 2 `the whole of the apparatus of the rst stage is displaceable with the carriage 12. For the purpose of anchoring the carriage 12 temporarily the pedestal 36 may carry a clamp adapted to co-operate with a suitable projection formed on the carriage and provided with a locking handle.

An insulating block 46 attached to a side member 13 of the carriage 12 carries a central contact 47 provided with a terminal 48 for attaching thereto a ilexible load (the load 49 in Figure 6). Mounted on the tloor adjacent to this contact 47 are two spaced brackets 50, 51, supporting between them two guide bars 52, 52 extending parallel with the direction of movement of the carriage. The guide bars 52, 52 support a block 53 of substantially rectangular section which is adapted to slide on the bars. An insulating plate 54 iixed to the top of the block 53 supports two spaced brackets 55, 55 carrying two contact blocks 56, 57 provided with suitable terminals 58, 59 for the attachment of flexible leads 60, 61 (Figure 6). These last mentioned contact blocks 56, and 57 are limit contacts and are disposed one on each side of the contact 47 which is xed to the carriage 12. When the carriage is in its normal position, the block 53 is in the central position as shown in Figure 4. The central contact 47 is formed with a cylindical surface and the contact surfaces on the limit contacts 56 and 57 are correspondingly recessed. Each bracket 50, 51 also supports an emergency limit switch 62 the operating lever 63 of which is adapted to be engaged by a Vertical end face 64 of the block 53 when this is displaced. towards its limiting position. The emergency limit switches 62, 62 are closed when not engaged by the block.

Referring now to the circuit diagram in Figure 6 there is shown a three- phase supply 65, 66, 67 adapted to be connected to the main motors, of which only the driving motor 9 for the capstan 8 is shown, by means of a main contactor 68. The hold-on coil 69 of this contactor is shown connected in series from one phase 67 through a normally closed stop switch 70, the two series-connected normally-closed limit switches 62, 62 and an auxiliary switch element 71 of the main contactor to another phase 65. The auxiliary switch 71 is short circuited by a connection 72 which includes a normally open pushbutton start switch 73. It will be seen that by closing the start switch 73 the coil 69 is energized, the main contactor 68 is closed and the start switch 73 is shortcircuited by the auxiliary switch 71 so that the contactor coil 69 remains energized. The reversible gear-control motor 11 for adjusting the speed of the capstan S is connected to the three- phase supply 65, 66, 67 either by a reverse contacter 74 or a forward contactor 75. The forward contactor 75 is operated by a coil 76 connected to the power supply line 65 and to the fixed limit contact 56 which will be engaged by the central contact 47 if the carriage 12 is forced back-wards due to the speed of the capstan 8 being too low. The engagement of these two contacts 47, 57 completes the circuit to the forward contactor coil 76 so that the contactor 75 closes and the motor 11 operates on the variable gear 10 to increase the speed of the capstan. When the limit contact 56 and central contact 47 separate with the return of the carriage 12 to its normal position the forward contactor coil 76 is de-energized and the motor 11 disconnected. The reverse contactor 74 is similarly operated by the engagement of the central contact 47 with the other limit contact 57 to close the circuit to the reverse contactor coil 77 when the carriage 12 is drawn forward as a result of the capstan 8 rotating too quickly. The reverse contactor 77 will open automatically when the carriage 12 returns to the normal position.

In the event of this automatic gear-changing device not operating as designed so that the undesirable tensiony or compression conditions are maintained, one of the emergency limit switches 62 will be .automatically opened by the movement of the block 53. It will be seen from the circuit diagram that the opening of either of the emergency limit switches 62 will automatically deenergize the hold-on coil 69 of the main contactor 68 so that the whole apparatus will be brought automatically to a standstill.

In place of the caterpillar haulage 6 the movement of the tube 4 through the welding position may be obtained by two pairs of grooved driving rollers, engaging the tube before and behind the welding position. The automatic adjustment of speed may be carried out on the rst or second drive, but it is preferred not to interfere with the speed of the tube through the welding position once this has been satisfactorily set. Also the speed adjustment may be effected through a motor-controller.

What I claim as my invention is:

1. In an arrangement for continuously processing a long rigid article moved along a line of travel through two successive process-stages by a separate forwarding device in each stage, automatic speed co-ordinating means for controlling the relative speeds of the forwarding de vices, said speed co-ordinating means comprising a carriage for one of the 4forwarding devices, suspending members supporting the carriage from fixed supports, centralizing springs incorporated in the suspending members, the springs being adapted to centralize the carriage and the suspending members being adapted to permit displacement of the carriage from the central position in the said line of travel under the action of tension and compression forces set up in the article between the two stages against the centralizing springs, a speed regulator for one of said forwarding devices, and control means for said speed regulator, said control means being adapted for operation by displacement of the carriage to adjust the speed regulator in the sense required to correct the condition which has caused the displacement.

2. In an arrangement for continuously processing a long rigid article moved along a line of travel through two successive process-stages by a separate forwarding device in each stage, automatic speed co-ordinating means for controlling the relative speeds of the forwarding devices, said speed co-ordinating means comprising a carage for one of the forwarding devices, suspending members supporting the carriage from fixed supports, dat plate springs incorporated in the suspending members to centralize the carriage and to permit it to move through a Short distance from a central position in the line of travel under the action of tension and compression forces set-up in the article between the two stages, the said plate springs being in planes transverse to the line of travel, non-flexible connections uniting the plate springs to the suspension members, to the carriage and to the said fixed supports, a speed regulator for one of said forwarding devices, and control means for said speed regulator, said control means being adapted for operation by displacement of the carriage to adjust the speed regulator in the sense required to correct the condition which has caused the displacement.

3. In an arrangement for continuously processing a long rigid article moved along a line of travel through two successive process-stages by a separate forwarding device in each stage, automatic speed co-ordinating means adapted to control the relative speeds of the forwarding devices, said speed co-ordinating means comprising a carriage for one of the forwarding devices, suspending members supporting the carriage from Xed supports, each of said fixed supports comprising a horizontal beam and two uprights together constituting a portal within which the carriage is disposed, each suspending member being a rectangular cross-braced frame with a plate spring rigidly joined to each upper corner of the frame and to the horizontal beam and a plate spring rigidly joined to each lower corner of the frame and to the carriage, the suspending members and springs being adapted to permit displacement of the carriage from a central position in the line of travel under the action of tension and compression forces set up in the article between the two stages, a speed regulator for one of said forwarding devices, and control means for said speed regulator, said control means being adapted for operation by displacement of the carriage to adjust the speed regulator in the sense required to correct the condition which has caused the displacement.

i References Cited in the file of this patent UNITED STATES PATENTS 989,045 Post Apr. 11, 1911 1,109,885 Webster Sept. 8, 1914 1,124,761 Lloyd Jan. 12, 1915 1,892,130 Benson Dec. 27, 1932 2,162,527 Cook June 13, 1939

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