US2885060A - Coil-removal guide means for bull-blocks - Google Patents

Description

May 5, 1959 E. A. DOBOSY COIL-REMOVAL GUIDE. MEANS FOR, BULL-BLOCKS 6 Sheets-sheaf. 1

Filed Jan. 9, 1958 INVENTOR ELMER A. Do aosY idmifi A ATTORNEYS.

May 5, 1959 Filed Jan. 9, 1958 COIL-REMOVAL GUIDE. MEANS FOR BULL-BLOCKS E. A. DOBOSY 6 Sheets-Sheet 2 IN VEN TOR ELMER A. Doe

A ATTORNEYS,

May 5, 1959 E. A. ,DoBosY 2, 5, 6

COIL-REMOVAL GUIDE MEANS FOR BULL-BLOCKS Filed Jan. 9, 1958 6 Sheets-Sheet 3 nu ur A L mIIEIHlm 6 p INVENTOR F2 g; 4 ELMER A. Doaosv A ATTORNEYS.

y 1959 E. A. DOBOSY 2,885,060

' COIIrRE MOVAL GUIDE MEANS FOR BULL-BLOCKS Filed Jan. 9, 1958 a Sheets-Sheet 4 Fig-5 INVENTOR ELMER A. Doaosv BY i;" We

A ATTORNEYS.

y 1959 E. A. DOBOSY 2,885,060

COIL-REMOVAL cum: MEANS FOR,BULL-BLOCKS Filed Jan. 9, 195a s Sheets-Sheet s INVENTOR ELMER A. D0505! mawm , A ATTORNEY;

May 5, 1959 Filed Jan. 9, 1958 E. A. DOBOSY 2,885,060

COIL-REMOVAL GUIDE MEANS FOR BULL-BLOCKS 6 Sheets-Sheet 6 64 2 2/ Q 1 5 F m P f 6 E 53 a l GE 3 CE A l g w; INVENTOR Q -Qgggggg ELMER 7L DoBosY lma q moq AA ATTORNEYS.

.Ps e tsd May 1 95.9

EOE-REMOVAL GUIDE MEANS FOR BULLBLOCKS iiinier A. Dobosy, Euclid, Ohio, assignor to Chase Brass "&"'Copper Co. Incorporated, Waterbury, ',Coun'.,' a cop.

This invention relates to metal drawing apparatus known as bull-blocks for drawing rods or tubes, and it relates more particularly to coil-removal guide means hq u app t 7 V Drawing drums have been used for sometime for drawing wirethrough a die, the wire being wound onto the drum which acts as a winch. Such drawing drums or bull blocks have only rather recently been used for drawing tubes or rods that had customarily been drawn on straight draw-benchesl The use of bull-blocks for drawing'tubes and rods has obvious advantages in being able tbjdrawmuch greater lengths of material at considerably higher speeds. Adaptation of the bull-block for drawingtubes and rods has, however, brought about many problems, due primarily to the greater size and weight of tubes and rods as compared to wire. V

Que of the problems has been in overcoming the difficulties arising as the coil is removed from the drum after a drawing operation. The drawing drum in apparatus now in use for tubes and rods is mounted for rotation'about a vertical axis and is suspended in inverted mannerat its upper end only, the lower end being free. Removal of the coils is accomplished by dropping them from the drum by gravity onto a receiving platform dire'ctly below the drum. Such platform is of necessarily rugged construction so as to withstand theforce of the heavy coil as it drops. In addition, the upper surface of the receiving platform must be substantially continuous and uninterrupted in order that the ends of the coils will not become caught as the coil expands in diameter with violent whipping of the ends and loops immediately after the drawing operation. Furthermore, since the coil is subsequently removed from the receiving platform by means of conveyor belts running transversely across the top of the platform, there must be nothing projecting above the upper surface of the platform which would inte'r fere with such conveyor belts or with the movement of the coil laterally when it is desired to remove it from the receiving platform.

In dropping to the receiving platform, the coils of tube or rod have heretofore not maintained a'uniforrn inside or outside coil diameter and they often become entangled.

As will be more apparent hereinafter, this is brought about by expansion of the loops in the coils and causes serious difiiculties in subsequent processing operations. Lack of uniform inside diameter of the coil, for example, prevents the'coil from being placed on a-pay-off reel fora future operation. Furthermore, if the loops in the coil become tangled, it is diflicult or impossible to pay-off the tube froma reel in the next operation. This is particularly serious where the apparatus for handling heavy tube or rod, with which the present invention is concerned, is capable of drawing at relatively high speeds, despite the size and weight of the material being drawn.

It is an object of the present invention to maintain uniform inside and outside'diameters of the coils as they are removed from an inverted drawing drum of the type described above, and to prevent entanglement of the coils;

2 Another object of the invent ion is to accomplishthis with simple, relatively inexpensive apparatus which automati sally centers and alignsithe coilsas they drop from the inverted drawing Apparatus constructed in accordance with the invention is provided with a plurality of coil-guiding rods mounted below the surface of the receiving platform of the bull-block and disposedvertically in parallel, spaced relationship to each other. These guide-rods are adapted to bemoved axially up through relatively small apertures in the top'of said platforminto coil-receiving position adj acent the lower end of thedrawing drum, the guide-rods being arranged in a ring generally oo-extensive with the periphery of the drawing drum, so that as the coil of tube or -rod drops from the drum it encircles the ring of guide' 'rods, which keep it centered and prevent the loops and ends of me on from becoming tangled. When the coil settles, the guide-rods are retracted .below the surface of the receiving platform where they do not interfere with removal of coil laterally from the platform by means "or the conveyor belt which extends across the plat-form. On the other hand, since the conveyor belt fits between the guide-rods, it does not prevent them from being extended upwardly above the surface of the platform.

U The invention will be more fully understood from the renewing description in conjunction with the accompanying drawings, in which Fig.1 is aside elevation of a bull-block for drawing tubes or rods and showing the coil removal guide means of'the present invention, certain parts of the bull-block being removed in order to expose the drawing drum;

Fig. 2's a plan view of the apparatus shown in Fig. 1;

Fig. 3 is aplan view of the coil-receiving platform;

Fig. 4 is a front elevation of the apparatus shown in Fi Fig. 5 is a plan of the conveyor system for storing the coils between draws;

' 'Figs. 6, 7 and 8 are more or less diagrammatic views of the drawing drum in side elevation, showing the op eration of the'coil removal guide means; and

I ig. 9 is a schematic view of a pneumatic system for operation of the coil-removal guide means.

"In' the drawings, A designates a tube drawing bullblock provided with an inverted drawing drum 10 arranged to rotate about a vertical axis during its operation. Drum 10 is suspended at its upper end on a shaft 12, the lower end of drum 10 being free for the automatic removal of a coil wound thereon during a drawing operation. A powerful main drive motor 13, capable of producing to 200 horsepower, drives the drawing drum through worm gears 14, 16, located in a gear housing above drum 10. The end of a tube 18 to be drawn is secured adjacent the top of drum 10 by means of a pneumatically operated clamp, shown diagrammatically at 20 in Fig. 1. Rotation of drum 10 in a clockwise direction as viewed from above will draw tube 18 through a reducing die 22. Immediately before passing through die 22, tube 18'travels through a set of straightening rolls 24 in order to eliminate bends in the tube and to guide it properly into die 22.

The tubes 18 to be drawn may be either straight or coiled when they are fed to the bull-block. Ordinarily, the first draw on the bull-block is made from straight tubes, conveniently placed at P (Fig. 5) with one end adjacent reducing die 22 to which they are fed. These straight lengths of tube may have been previously drawn to as much as 210 feet in length on a drawbench. After the first draw on the bull-block, the tubing is of course'in coiled form and these coils may then be redrawn on the same machine any number of times to the desired diameter, wall thickness and length. In order to guide assume lie in even turns along the length of the drum, the die 22 and straightening rolls 24 are mounted on a movable tray 26 which travels vertically from an upper starting position shownin Fig. 1 to afinish position adjacent the lower'end of drum. inwhicli'tra'y 26 is shown in broken lines. Upon completion of the'drawing operation on each coil, the tray 26 is returned'to 'its starting position where the next length of tube is fed1to the machine. In cases where the tube to be drawn has been previously coiled, it lies horizontally on a pay-off reel 27 on top of tray 26 as partially shown in Figs. 1 and 2. Tray 26 is raised and lowered by means of hydraulic cylinder 29 which is adapted to lower the tube 18 in synchronism with the speed of the drawing drum 10 so that-the-tube lies in even, closely spaced turns on the drum.

As the trailing end of the tube 18 is drawn through die 22, a load relay in the die causes the clamp 20 on the drawing drum to automatically release the starting end of the coil 28 (Fig. 6), which immediately springs outwardly as it increases in diameter. This increase in the diameter of the coil from the drum size makes the free ends of the coil whip rapidly in opposite directions around the drum. coil immediately after it has been drawn has caused considerable dilficulty in the use of bull-blocks of this type, particularly where they are used to draw tube up to ;as much as 3000 feet long, as some ofthe bull-blocks now being used are designed to do. For example, whenfjthe coil is free of both the die 22 and clamp 20 and has begun to expand, it immediately drops from the drum by'gravity onto a receiving table 30 directly below the As soon as it is free of the end of drumltl'and while'it is still expending in diameter, some of the loops'tend to' expand more rapidly than others, even causing some to be reduced in diameter, rather than enlarged, so that when the coil finally comes to rest on the table 30, its'loops vary widely in diameter. This makes it diflicult for the coil to be placed on the pay-oif reel 27 for future operations on the same machine or on similar reels for another machine. Nonuniformity of theoutside diameter of the coils causes difiiculties not only on the pay-01f reels,

In the past, the rapid expansion of the from the bu1l-block a sufficient distance to permit a predetermined number of coils to be stored on it one'after the other as they come from the bull-block.

In a typical coil handling system for a bull-block having a 60" diameter drawing drum, conveyor 48 may extend horizontally some 50 to 60 feet away from the bullblock to a position where a transfer car 50 receives the coils andcarries them transversely to another conveyor 52 running parallel to conveyor. 48 but in the opposite direction. Conveyor 52 carries the coils back to a feed-. ing station C at the bull-block where the end of each coil is swaged in order to start it through the drawing die 22, which is changed to a smaller size when the first length of tubing. to .be drawn returns. ,In order to avoid the necessity for frequently changing the, drawing dies, some twenty coils (depending on the diameter of the coils and the length of conveyors 48 and 52) are drawn consecutively through a die of one particular size,.each coil thus drawn being dropped onto the receiving table 30, which. carries it out from under the bull-block to the unloading station B where belts 32 discharge it totake-awaycon veyor 48. The coils then travel along conveyor 48, 50 and 52 to feeding station C. Conveyors 48, 50 and52. are automatically timed to synchronize with the drawing operation and to move the coils intermittently a distance substantially equal to the diameter of the coils. This requires properindexing of the conveyors so that they will move just the right distance upon completion of each: draw. It will be readily apparent, therefore, that if the outside diameters of the coils coming from the bull-block are not fairly" uniform, the automatic conveyor system will not function properly, due to the fact that ajcoil may takeup 'more space than it should. thereby crowding the coils oneither sideof it. Machines of the general type described hereinabove for use in drawing'tubes and rods of relatively large diameter are a comparatively recent development, making A possible the drawing of tubes of much greater length at higher speeds than had been feasible before. The" but also in proper indexing of automatic conveyors used I :3 handle these coils, as will'be more apparent hereinter. Furthermore, as the coil 28 (Figs. 6-8) expands and drops off drum 10, the loops may becomeentangled, dam aging the tubing in many instances and'causing loss 'of time'in untangling them so that the coils will pay out properly during subsequent operations. It will be readily appreciated that uninterruptedfeeding of the tube to' the drawing drum is extremely important in bull-blocks of the type here contemplated, which are capable of drawing speeds of from 150 to 2,000 feet per minute, depending on the'size of the tube. Therefore, if the loops in a coil become tangled, as they have been frequently'found to do heretofore in using inverted drawing drums, proper feeding is impossible, thereby greatly detracting from the advantages of this type of machine and reducing the quality of the product produced due to damage to the tubes. In order to revove the coil 28 from the receivingtable 30, endless conveyor belts 32 are provided across the top of table 30. -Belts 32, which slide along the'supporting' upper surface 34 of table 30, travel over rollers 36 and 38 at opposite ends thereof, roller 36 being driven by motor 40 through a driving arrangement shown at'42 (Figs. 1 and 3). Operation of conveyor belts 32 may be"controlled automatically or by an operator at asu'itablecontrolstation, not shown. As illustrated in the drawings, *table 130 ma yibe mounted on wheels 44 for movement along tracks 46, so

that it can be moved out fromlunder drum 10to an unloading station B (Fig. 5) where it is in line with a take-away conveyor 48 to which the coil is transferred.

The take-away conveyor, 'so-called, carries the coils, away present invention resides in the provision of means ifori maintaining uniform inside and outside diameters of the coils removedfrom the drawing drum in apparatus of this type and for preventing entanglement of vthe-loops in such coils. To this end, receiving table 30, onto which the drop from the drum 10, is provided with several retractable guide-rods projecting vertically upward through apertures 62 in the upper surface 34 of table 301 In the particular apparatus shown in the drawing'sf or illustrative purposes, eight such guide-rods are used, these being arranged in spaced relation in a circle (Figs 3) such that theside of each rod 60 outwardly of the circle is slightly within the periphery of the drum 10.

'. For example, if the drum 10 is sixty inches in diameter between them and become entangled.

and rods 60 are each two inches in diameter, the centers of rods 60 will desirably be located on a circle which is 55 /2 inches in diameter and has its center located on the axis of drum 10. V

Guide-rods 60 are in this instance the upper ends of the piston rods of double-acting air cylinders 64 which are mounted on table 30 belowits upper surface 34. As shown in Fig. 1, cylinders 64 project rods 60 upward to a point close tothe bottom edge of drum 10, in order to receive and guide the coil at the finish of the drawing operation. Since the loops of the coil flail about severely as the coil expands, it is important that as little space as possible be'left between the ends of the guide-rods 60 and the bottom of drum 10 so that the. loops can not'slip In fact, if'n'eed be, the ends of rods 60 can extend slightly up inside drum 10 thereby virtually eliminating any possibility of the tubing slipping inside guide-rods 60. In order to securely mount rods 60 against the harsh 1 thrashing. of the coils as they drop from the drum, an

of each cylinder 64 just below the upper surface 34 of table 30. Bearing blocks 65 are rigidly secured by means of bolts 66 to cross-members 67 of the frame of table 30, cylinder 64 being mounted in any suitable manner on the lower end of block 65. Rod 60 projects upwardly from cylinder 64 through bearing block 65 which, due to its considerable length and heavy construction, prevents any transverse or twisting movement of the guide-rod 60. In the particular apparatus disclosed herein for illustrative purposes only, bearing blocks 65 are desirably made of cast iron, being 8 inches long with a 2-inch inside diameter to slidingly receive rods 60 which move longitudinally therein. Each guide-rod 60 is long enough so that when its piston 68 (Figs. 8 and 9) is at its lowest or retracted position in cylinder 64, the upper end of rod 60 is flush with or slightly below the upper surface 34 of table 30. In the so-called 60" bull-block depicted in the drawings, the upper surface of table 30 may be about 13 or 14 inches from the bottom end of drum 10. Rod 60 and its power cylinder 64 must, therefore, be long enough to provide a 13 or 14 inch stroke so that rods 60 can be extended from their fully retracted positions, where they are flush or below the surface 34, to their coil receiving position adjacent the bottom of drum 10. A suitable power cylinder for this purpose is a Miller Air Cylinder, Model A61, having a predetermined stroke of from 13 to 14 inches, a 2" diameter piston rod and double-acting piston with a 3%" bore.

Conveyor belts 32 are arranged to travel between guide-rods 60 with a wide belt 32a provided in the middle between two groups of four equally spaced rods 60 on either side of the position on table 30 directly below drum 10. Narrower belts 32b may be provided as shown between the pairs of rods 60 on both sides of belt 32a, but these are not essential as belt 32a alone is usually capable of removing the coil.

With reference more particularly to the schematic views of Figs. 6 to 8, operation of the coil removal guide means bereinabove described is as follows: When the tube 18 is started on drum and with table 30 in position under the drum, guide-rods 60 are raised in their coil receiving position (Fig. 6). As has already been described hereinbefore, tube 18 is drawn through die 22, and the resulting coil 28 drops off drum 10 upon completion of the draw to the position shown in Fig. 7. Guiderods 60 thus prevent coil 28 from becoming tangled, when it leaves the end of drum 10 and encircles the guide-rods as it falls onto table 30, thereby keeping the loops of the coil in their correct order and ensuring that they remain fairly uniform in diameter, as shown for example in Figs. 7 and 8. Coil 28 continues to expand even after it is on table 30, with the free ends of the tube being whipped about within shielding, indicated generally at 69, which may be placed around the drawing drum 10. When the coil 28 finally settles, guide-rods 60 are lowered, and table 30 is then moved to position B (Fig. 5). If the guide-rods extend above the bottom edge of drum 10 when in their coil receiving position, it is of course essential that the guide-rods 60 be retracted at least part way before table 30 starts to move out from under the drum to position B where it is in line with conveyor 48. With the guide-rods 60 fully retracted below the upper surface 34 of receiving table 30, as shown in Fig. 8, coil 28 is free to be moved laterally by means of belts 32 onto take-away conveyor 48.

While guide-rods 60 are shown and described herein, as being pneumatically operated, it will be understood of course that a hydraulic system could be used in place of the air system specifically disclosed. For that matter, some other mechanical means of lifting and retracting guide-rods 60 could be used if found to be desirable. Fig. 9 shows an air system suitable for the purpose, only one cylinder 64 being illustrated in the drawing for the sake of simplicity. When the guide-rods are in theircoil receiving position, compressed air from a source S is connected to the lower side of cylinders 64 through a solenoid-operated reversing valve and a header 72, which distributes the air to all the cylinders simultaneously. The upper ends of the cylinders 64 are vented to the atmosphere through a second header 74 back to the reversing valve 70 where the return line opens to the atmosphere as shown. When it is desired to remove a coil 28 from table 30 upon completion of a drawing operation, a control switch (not shown) operates a solenoid on reversing valve 70, placing this valve in its alternate position in which cross passages 76 connect header 74 to the air supply S so that air under pressure is fed to the upper ends of cylinders 64. At the same time valve 70 also exhausts the lower ends of said cylinders through header 72. Pistons 68 will then move downward, retracting guide-rods 60 below the surface of table 30, so that the coil can be removed therefrom by means of belt conveyor 32. Since various types of reversing valves could be used in the control system for operating guide-rods 66, valve 70 is shown purely diagrammatically in Fig. 9 as having a sliding block movable to the desired position by a solenoid, which is energized either by manual or automatic controls.

What is claimed is:

1. In a bull-block for drawing ductile metal in the form of tubes or rods, wherein said bull-block has an inverted drawing drum mounted for rotation about a vertical axis to permit a coil wound thereon during the drawing operation to drop free thereof onto a receiving platform having a substantially continuous upper supporting surface spaced from the lower end of the drum, the combination therewith of coil removal guide means comprising a plurality of vertically disposed coil guide-rods mounted in spaced relation from each other below the upper surface of said platform for reciprocal movement axially from a retracted position at least substantially flush with said upper surface, to a coil-receiving position adjacent the lower end of said drum, said guide-rods being arranged in a circle not substantially larger in diameter than the diameter of said drum and coextensive therewith, said platform having apertures adjacent each of said guide-rods through which said guide-rods reciprocate into and out of coil-receiving position, belt conveyor means extending across and supported by the upper surface of said platform between said guide-rods for discharging a coil laterally from said platform, and power means for moving said guide-rods upward into said coilreceiving position and for retracting them to their coildischarge position.

2. The combination defined in claim 1, wherein said power means comprises a fluid system having individual double-acting power cylinders for each of said guiderods.

3. The combination defined in claim 2, in which each of said guide-rods is provided with a bearing block rigidly secured to said platform adjacent the upper surface thereof with one of said power cylinders depending from said bearing block below said platform.

4. The combination defined in claim 1, wherein eight such guide-rods are provided and said belt conveyor means includes a relatively wide belt located centrally of said platform with half said guide-rods located on one side of said belt and half on the other, the guide-rods on each side of said belt being equally spaced from each other and in pairs, the guide-rods in each of said pairs being located on a line parallel to the direction of travel of said belt.

References Cited in the file of this patent UNITED STATES PATENTS

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