US3274816A - Machine for tapering tubing - Google Patents

Machine for tapering tubing Download PDF

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US3274816A
US3274816A US310417A US31041763A US3274816A US 3274816 A US3274816 A US 3274816A US 310417 A US310417 A US 310417A US 31041763 A US31041763 A US 31041763A US 3274816 A US3274816 A US 3274816A
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rollers
stock
carriage
swaging
machine
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US310417A
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Held Richard Anthony
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    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21DWORKING OR PROCESSING OF SHEET METAL OR METAL TUBES, RODS OR PROFILES WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21D41/00Application of procedures in order to alter the diameter of tube ends
    • B21D41/04Reducing; Closing
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21BROLLING OF METAL
    • B21B21/00Pilgrim-step tube-rolling, i.e. pilger mills
    • B21B21/005Pilgrim-step tube-rolling, i.e. pilger mills with reciprocating stand, e.g. driving the stand
    • BPERFORMING OPERATIONS; TRANSPORTING
    • B21MECHANICAL METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL; PUNCHING METAL
    • B21CMANUFACTURE OF METAL SHEETS, WIRE, RODS, TUBES OR PROFILES, OTHERWISE THAN BY ROLLING; AUXILIARY OPERATIONS USED IN CONNECTION WITH METAL-WORKING WITHOUT ESSENTIALLY REMOVING MATERIAL
    • B21C37/00Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape
    • B21C37/06Manufacture of metal sheets, bars, wire, tubes or like semi-manufactured products, not otherwise provided for; Manufacture of tubes of special shape of tubes or metal hoses; Combined procedures for making tubes, e.g. for making multi-wall tubes
    • B21C37/15Making tubes of special shape; Making tube fittings
    • B21C37/16Making tubes with varying diameter in longitudinal direction
    • B21C37/18Making tubes with varying diameter in longitudinal direction conical tubes

Definitions

  • the carriage 40 also includes two shafts 64 and 66 which oscillatively support two rollers 68 and 70 respectively. These shafts and rollers are disposed parallelly, one above the other and transversely of the sleeves 42 of the carriage.
  • the lower roller 68 has two series of teeth 72 and 74 which mesh, respectively, with the teeth on track sections 56 and 62, and the upper roller is provided with two series of teeth 76 and 78 which mesh, respectively, with the teeth on track sections 58 and 60.
  • the shafts 64 and 66 are secured to the carriage 40 by bolts 80 and to one another by bolts 82.
  • the top 176 of the template 162 provides a track for a roller 17 8, which latter is attached to lever 126.
  • Lever 126 is pivoted to frame extension 118 by a trunnion 182.
  • Lever 126 extends between the contact switch 124, which latter controls the direction of movement of the motor 122.
  • the switch When the roller 178 is lowered, the switch will be actuated to cause the motor to operate in a direction in which the shafts 94 and 96 are lower and thereby decrease the movement of the swaging roller to the left.

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  • Engineering & Computer Science (AREA)
  • Mechanical Engineering (AREA)
  • Forging (AREA)

Description

Sept. 27, 1966 HELD MACHINE FOR TAPERING TUBING 5 Sheets-Sheet 1 Filed Sept. 20, 1963 INVENTOR.
RICHARD A. HELD A TTOR'NEYS Sept. 27, 1966 R. A. HELD MACHINE FOR TAPERING TUBING Filed Sept. 20, 1963 5 Sheets-Sheet 2 INVENTOR.
R/CHARD A. HELD 9M 5% M J- ATTORNEYS Sept. 27, 1966 R. A. HELD MACHINE FOR TAPERING TUBING 5 Sheets-Sheet 5 Filed Sept. 20, 1963 a n. m s m E H n N Hwy \mm\ m M V M W R k T u m A T mm M @W A vs 9m R Y B United States Patent 3,274,816 MAfil-HNE FOR TAPERING TUBING Richard Anthony Held, Rte. 1, Box 90433, Ramona, Calif. Filed Sept. 20, 1963, Ser. No. 310,417 4 Claims. (Cl. 72-189) The present invention relates to a machine for and the method of changing elongated stock, such as a rod or tube, having a substantially uniform thickness or diameter, to stock having various degrees of taper.
The machine, for carrying out the steps in the method, comprises die means having elongated and confronting swaging surfaces, one of the surfaces being disposed at an angle with respect to the other. Means is provided for progressively moving, for swaging effect, one of the elements longitudinally of the other. In the preferred embodiment, the stock is progressively fed into the die means. Means is provided for varying the linear extent of the swaging effect of the swaging surfaces on the stock whereby various degrees of taper can be obtained.
Means is synchronized with the progressive movement of the said moved element (herein the progressive movement of the stock), which means is in the form of a template, and the means for varying the extent of linear movement, imparted to the swaging surfaces, is controlled by the template.
The machine is so designed that at least one of the swaging surfaces is oscillated relative to the other swaging surface, and the degree of oscillation can be varied. In the preferred embodiment, both swaging surfaces are oscillated concomitantly, and the degree of oscillation is varied.
At least one of the swaging surfaces is in the form of a groove which increases in depth linearly. Preferably both swaging surfaces are in the form of a groove, the grooves being allochiral and are oscillated concomitantly.
Too, in the preferred embodiment, each groove is semicircular in transverse cross section. Also, in the preferred embodiment, the grooved surfaces are formed in coasting rollers.
Other features and the advantages of the present invention will be apparent from the following description, reference being had to the accompanying drawing wherein a preferred embodiment of the invention is illustrated.
In the drawings:
FIG. 1 is a fragmentary, for carrying out the method;
FIG. 2 is a fragmentary, front view of the machine, looking in the direction of arrow 2 in FIG. 1;
FIG. 3 is a fragmentary view, partly in section, the section being taken along line 3-3 of FIG. 2;
FIG. 4 is a front view of the machine, partly diagrammatic, and on a smaller scale;
FIG. 5 and FIG. 6 are fragmentary views, partly in sections, the sections being taken along lines 55 and 66, respectively of FIG. 4; and
FIG. 7 is a fragmentary view partly in section and looking in the direction of arrow 7 in FIG. 4, but on a larger scale.
Referring in detail to the drawings, the machine comprises an elongated main frame 22 including four legs 24 which support two parallelly disposed and space elongated and horizontally extending angle iron frame members 26 and 28 which are fixed with one another by suitably transverse angle iron 30 and iron I- b'eams 32 and 34.
The I- beams 32 and 34 carry two guide bars 36 and 38. These bars are spaced from one another, extend longitudinally of the frame members 26 and 28 and lie above the frame members. These bars lie in the same horizontal plane. A carriage 40 is guided by these bars.
top plan view of the machine The carriage comprises two sleeves 42 and 44 which encircle the bars 36 and 38, respectively; a transversely extending shaft 46 depends from and is fixed to the sleeves. The ends of this shaft are connected with a pair of connecting rods 48 and 50.
Two tracks 52 and 54 are carried in any suitable manner by the beams 32 and 34. These tracks extending parallelly of one another and with the guide bars 36 and 38, and lie in substantially the same horizontal plane as the bars. The rear track 52 is provided with a series of transversely extending teeth on the bottom thereof, to form a track section 56, and a series of transversely extending teeth 58 on the top thereof to form another track section. Track section 56 is disposed rearwardly of track section 58. The front track 54 is provided with a series of transversely disposed teeth on the top thereof to form a track section 66, and a series of transversely disposed teeth on the bottom thereof to form a track section 62.
The carriage 40 also includes two shafts 64 and 66 which oscillatively support two rollers 68 and 70 respectively. These shafts and rollers are disposed parallelly, one above the other and transversely of the sleeves 42 of the carriage. The lower roller 68 has two series of teeth 72 and 74 which mesh, respectively, with the teeth on track sections 56 and 62, and the upper roller is provided with two series of teeth 76 and 78 which mesh, respectively, with the teeth on track sections 58 and 60. The shafts 64 and 66 are secured to the carriage 40 by bolts 80 and to one another by bolts 82.
The rollers 68 and 70 are provided with grooves 84 and 86, respectively, on the peripheries thereof. These grooves are each semi-circular in cross section and taper substantially to infinity. The rollers are so set with respect to one another that the mating grooves are allochiral throughout their oscillative range whereby a complete circular groove is maintained by the grooves throughout their range of oscillation. The circular groove gradually diminishes in diameter as the rollers are moved to the left, as viewed in FIGS. 1, 2 and 4.
The rollers are caused to oscillate by pulling and pushing action on the connecting rods 48 and 50. The upper ends of these rods are pivotally connected with shaft 46 and the lower ends are pivotally connected to a shaft 88. Thus it will be understood that as the crank arms 48 and 50 pull the carriage 40 to the left, causing rotation of the rollers 68 and 70 in counter-clockwise and clockwise directions, respectively and simultaneously, tapering type swaging action will be imparted to stock when subjected to the rolling action of the rollers. Such stock is shown at 87.
Shaft 88 carries two sleeves 90 and 92 at opposite ends thereof; these sleeves are slidable on shafts 94 and 96 respectively. The lower ends 98 of these shafts 94 and 96 are provided with reverse bends 100 and the ends thereof are pivotally supported at 102 on frame extensions 104 and 108. Thus the shafts 94 and 96 are free to oscillate about pivots 102. A transversely disposed shaft is suitably journaled on the upper portions of shafts 94 and 96, and shaft 110 carries a pinion 112. This pinion meshes with a toothed rack 114. This rack is pivotally supported at 116 to a frame extension 118. The pinion is rotated through reduction gear 120 by an. electric motor 122 of the reversible type.
The motor is controlled by limit switches 124, each having a plurality of sets of contacts. These contacts are controlled by a lever 126. When the lever 126 is in a neutral position, the motor is inoperative. In another position, the motor rotates in one direction, and when in still another position, the motor operates in the opposite direction. It is apparent that when the motor is rotated in one direction, the shafts 94 and 96 will be moved,
through the rack and pinion, in a clockwise direction, and when the motor rotates in the opposite direction, the shafts 94 and 96 will be in a counterclockwise direction.
The shaft 88 is reciprocated by a connecting rod 130 which is suitably journaled on the shaft as at 132. This connecting rod is reciprocated by a crank arm 134 which is journaled on a frame part 136 at 138. Thus, it is apparent that the length of the stroke of the connecting rods 48 and 50, toward the right as viewed in the drawings, is governed by the position of these shafts 94 and 96. When the shafts 94 and 96 are in the highest position, substantially as shown in the drawings, the stroke of rods 48 and 50 is the longest. The strokes of the rods 48 and 50 are gradually decreased as the shafts 94 and 96 are lowered. Due to the pivotal arrangement 102, for the shafts 94 and 96, the end of the stroke toward the left is substantially constant, regardless of the range of movement of the shafts 94 and 96.
Reciprocation of the rods 48 and 50 effects reciprocation of the carriage 40, and reciprocation of the latter effects oscillation of the rollers 68 and 70. Since the extent of movement of the rods to the right is substantially constant, the point of stopping of the carriage at the right end of the stroke of the carriage is substantially constant. Therefore, the position of the rollers 68 and 70 at the right end of the stroke is substantially constant. The rollers are so positioned with respect to the tracks that at the extreme right position thereof, the widest and deepest sections of the grooves are in complementing relationship. As the rollers gradually move to the left, the confronting width and depth of the grooves gradually decrease.
Since the increment of change in width and depth of the grooves 84 and 86 is constant, the swaging effect on stock, which is progressively advanced to the left is constant. If full strokes of the carriage are maintained, which full strokes each comprehend a movement of the rollers from a position in which the widest and deepest groove portions confront one another to a position in which the narrower and less shallow portions of the grooves confront one another, then a constant angling taper is found on the stock. If a lesser degree of taper on the same stock is desirable, after part of the stock has been tapered as previously described, then in that event, the stroke of the carriage to the left is shortened, resulting in a shorter movement of the rollers to the left. In this manner any lesser degree of taper can be progressively obtained.
The stock to be tapered may be a rod or tube of any cross-sectional configuration; it is shown herein as a tube 87 formed of aluminum alloy. It is advanced to the left by being suitably connected to a carriage 142. This carriage slides on the frame members 26 and 28 and is chased by a worm 144. The worm is journaled in suitable bearings 146 and 148. The worm has a gear 150 afiixed thereto, which latter is driven through a gear 152. This gear 152 and the crank arm 134 are synchronized and are rotated through suitable gear reduction and a motor (not shown).
It is desirable to rotate the stock one-third turn, or less, at the conclusion of each right phase of the oscillation of the rollers. When the rollers are in the extreme right position, the circle provided by the grooves 84 and 86 is slightly larger than the diameter of the tube 87, whereby the tube can be turned; any suitable means may be employed for turning the tube. A switch 154 can be closed by being engaged by the carriage 40 at the conclusion of each right stroke of the carriage, causing energization of a motor or solenoid 156. This solenoid includes a dog 158 attached to the core thereof, and the dog cooperates with a ratchet wheel 160 fastened to the tube 87.
The raising and lowering of the shafts 94 and 96 are controlled by controlling the direction of movement of h the motor 122. This is accomplished by the use of a template 162 and the movement of the carriage 142. A track 164 is carried by frame member 28. It is arranged longitudinally of this frame member and parallelly of screw or worm 144. A carriage 166 is carried by the track 164 and is attached to carriage 142 by a rod 168. Rollers 170 are attached to the carriage 166 and ride upon track 164. Template 162 is removably fixed to the carriage 166 by screws 172 and by rod 174.
The top 176 of the template 162 provides a track for a roller 17 8, which latter is attached to lever 126. Lever 126 is pivoted to frame extension 118 by a trunnion 182. Lever 126 extends between the contact switch 124, which latter controls the direction of movement of the motor 122. When the roller 178 is lowered, the switch will be actuated to cause the motor to operate in a direction in which the shafts 94 and 96 are lower and thereby decrease the movement of the swaging roller to the left.
Thus, it is apparent from the foregoing that various degrees of taper can be effected by a single set of dies by merely varying the linear extent of movement between the stock being worked upon by the dies.
while the form of embodiment herein shown and described, constitutes preferred form, it is to be understood that other forms may be adopted falling within the scope of the claims that follow.
I claim:
1. A machine for changing a uniform outside diameter stock such as a rod or tubing to stock having a taper on the outer surface, said machine comprising in combination:
(A) a frame forming (1) an elongated guide;
(B) a carriage guided by and movable longitudinally of the guide;
(C) die means carried by the carriage, said die means forming swaging surfaces which, in conjunction, are circular in cross section, which decrease in width constantly for tapering stock, said die means including:
(1) a pair of rollers, each roller having on the periphery thereof, a swaging surface arranged allochirally, said surfaces being semicircular and gradually decreasing in depth radially, said surfaces of the rollers confronting one another when oscillatory movements are imparted to the rollers;
(D) means for reciprocating the carriage along the guide and for simultaneously effecting oscillatory movements in opposite directions to the rollers;
(E) movable means for progressively feeding stock longitudinally thereof between the swaging surfaces of the rollers;
(F) means synchronized with and movable with the movement of the movable stock feeding means and forming a template;
(G) and means governed by the movement of the template for varying the degree of oscillating movements imparted to the roller by varying the length of reciprocating movements imparted to the means (D) for reciprocating the carriage.
2. A machine as defined in claim 1, characterized to include:
(H) means synchronized with the movement of the carriage for causing turning movement to be imparted to the stock at the conclusion of the strokes of one direction of movement of the carriage.
3. A machine as defined in claim 1, characterized in that the means (G) includes:
(1) a lever forming a guide;
(2) means pivotally connecting the lever guide to the frame;
(3) an element carried by and guided along the lever;
( a connecting rod connecting the element and the leve (5) a rotatable element for reciprocating the first mentioned element along the lever;
(6) and means movable with the template and connected with the lever for moving the lever about the pivot means.
4. A machine as defined in claim 1, characterized in that the surfaces on the rollers forming the largest diammeter have a diameter greater than that of the stock; and further characterized to include:
(H) means synchronized with the movement of the carriage for causing turning to be imparted to the stock at the time the largest diameter surfaces of the rollers surround the stock.
References Cited by the Examiner CHARLES W. LANHAM, Primary Examiner.
H. D. HOINKES, Assistant Examiner.

Claims (1)

1. A MACHINE FOR CHANGING A UNIFORM OUTSIDE DIAMETER STOCK SUCH AS A ROD OR TUBING TO STOCK HAVING A TAPER ON THE OUTER SURFACE, SAID MACHINE COMPRISING IN COMBINATION: (A) A FRAME FORMING (1) AN ELONGATED GUIDE; (B) A CARRIAGE GUIDED BY AND MOVABLE LONGITUDINALLY OF THE GUIDE; (C) DIE MEANS CARRIED BY THE CARRIAGE, SAID DIE MEANS FORMING SWAGING SURFACES WHICH, IN CONJUNCTION, ARE CIRCULAR IN CROSS SECTION, WHICH DECREASE IN WIDTH CONSTANTLY FOR TAPERING STOCK, SAID DIE MEANS INCLUDING: (1) A PAIR OF ROLLERS, EACH ROLLER HAVING ON THE PERIPHERY THEREOF, A SWAGING SURFACE ARRANGED ALLOCHIRALLY, SAID SURFACES BEING SEMICIRCULAR AND GRADUALLY DECREASING IN DEPTH RADIALLY, SAID SURFACES OF THE ROLLERS CONFRONTING ONE ANOTHER WHEN OSCILLATORY MOVEMENTS ARE IMPARTED TO THE ROLLERS; (D) MEANS FOR RECIPROCATING THE CARRIAGE ALONG THE GUIDE AND FOR SIMULTANEOUSLY EFFECTING OSCILLATORY MOVEMENTS IN OPPOSITE DIRECTIONS TO THE ROLLERS; (E) MOVABLE MEANS FOR PROGRESSIVELY FEEDING STOCK LONGITUDINALLY THEREOF BETWEEN THE SWAGING SURFACES OF THE ROLLERS; (F) MEANS SYNCHRONIZED WITH AND MOVABLE WITH TE MOVEMENT OF THE MOVABLE STOCK FEEDING MEANS AND FORMING A TEMPLATE; (G) AND MEANS GOVERNED BY THE MOVEMENT OF THE TEMPLATE FOR VARYING THE DEGREE OF OSCILLATING MOVEMENTS IMPARTED TO THE ROLLER BY VARYING THE LENGTH OF RECIPROCATING MOVEMENTS IMPARTED TO THE MEANS (D) FOR RECIPROCATING THE CARRIAGE.
US310417A 1963-09-20 1963-09-20 Machine for tapering tubing Expired - Lifetime US3274816A (en)

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Cited By (4)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3483728A (en) * 1966-01-31 1969-12-16 Dalmine Spa Process and device for drawing truncated-cone shaped bodies and the like
US3845649A (en) * 1972-06-26 1974-11-05 Wean United Inc Tube production
US4494704A (en) * 1982-01-12 1985-01-22 L.C.C.-C.I.C.E.-Compagnie Europeenne De Compsants Electroniques Process and device for manufacturing mother capacitors by helical winding
EP0381116A2 (en) * 1989-02-02 1990-08-08 WEICHHART GmbH Method and apparatus for shaping metal tubes into conical or tapering bodies

Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US1810885A (en) * 1927-10-31 1931-06-16 George E Neuberth Method of tapering metal tubes
US2054370A (en) * 1933-01-24 1936-09-15 Gross Fritz Apparatus for making conical tubular bodies
CA480119A (en) * 1952-01-08 See Fabriks Aktiebolag Method of rolling out tubes in pilgrim rolling mills and equipment therefor

Patent Citations (3)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
CA480119A (en) * 1952-01-08 See Fabriks Aktiebolag Method of rolling out tubes in pilgrim rolling mills and equipment therefor
US1810885A (en) * 1927-10-31 1931-06-16 George E Neuberth Method of tapering metal tubes
US2054370A (en) * 1933-01-24 1936-09-15 Gross Fritz Apparatus for making conical tubular bodies

Cited By (6)

* Cited by examiner, † Cited by third party
Publication number Priority date Publication date Assignee Title
US3483728A (en) * 1966-01-31 1969-12-16 Dalmine Spa Process and device for drawing truncated-cone shaped bodies and the like
US3845649A (en) * 1972-06-26 1974-11-05 Wean United Inc Tube production
US4494704A (en) * 1982-01-12 1985-01-22 L.C.C.-C.I.C.E.-Compagnie Europeenne De Compsants Electroniques Process and device for manufacturing mother capacitors by helical winding
US4630784A (en) * 1982-01-12 1986-12-23 L.C.C.-C.I.C.E.-Compagnie Europeenne Des Composants Electroniques-36 Process and device for manufacturing mother capacitors by helical winding
EP0381116A2 (en) * 1989-02-02 1990-08-08 WEICHHART GmbH Method and apparatus for shaping metal tubes into conical or tapering bodies
EP0381116A3 (en) * 1989-02-02 1991-05-08 WEICHHART GmbH Method and apparatus for shaping metal tubes into conical or tapering bodies

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