US2474276A - Apparatus for making sinuous bends in long workpieces - Google Patents

Description

2 Sheets-Sheet 1 June 28, 1949. A. w. PAYNE APPARATUS FOR KING SINUOUS BENDS IN LONG WORKPIECBS Filed lay B, 1947 June 28, 1949- w, PAYNE 2,474,276

APPARATUS FOR MAKING smuous nmms IN LONG WORKPIECES Filfid m 8, 1947 2 51166128411691. 2

INVEN TOR.

Arthur M. Payne A T7ORNE Y5.

Patented June 28, 1949 APPARATUS FOR MAKING SINUOUS BENDS IN LONG WORKPIECES Arthur W. Payne, Detroit, Mich, assignor to Bundy Tubing Company, Detroit, Mich, a corporation of Michigan Application May 8, 1947, Serial No. 746,706

11 Claims. 1

This invention relates to an apparatus for forming long work pieces, such as a tube, into coils of serpentine shape having a series of reverse bends.

When an elongated piece of stock, such as a tube, is formed into a serpentine coil by the successive making of reverse bends therein, a problem is immediately encountered in the handling of the work. In some operations some of the stock is required to be swung through the angle of the bend relative to other portions of the stock and since the stock, in its initial form is quite long, it is usually the practice to swing the formed portions of the coil relative to the straight run of stock. As the coil builds up in size, this manipulation of the coil becomes increasingly diflicult. Some rather involved mechanical devices have been made to perform this work.

One of the objects of the present invention is to provide an apparatus for making serpentine coils of a simplified nature wherein a minimum of manipulating movements of the stock is required during the bending operations. To this end, the invention aims to provide an apparatus wherein two reverse bends are simultaneously made and wherein the formed portions of the coil remain substantially at rest during the bending operations with the stock moving substantially only lengthwise in order to provide the necessary length of tube required to form the runs and bends of the coil.

Other objects will become apparent as the following detailed description is considered in conjunction with the accompanying drawings wherein one apparatus for carrying out the invention is disclosed:

Fig. 1 is a general side elevational view of an apparatus constructed in accordance with the invention showing several positions of an op erating part in dotted lines.

Fig. 2 is a top plan view showing the support or table and some of the operating parts.

Fig. 3 is a sectional view taken substantially on line 3--3 of Fig. 1 showing a clamp and bending arbor.

Fig. 4 is a sectional view taken substantially on line 4-4 of Fig. 1 showing the yieldable mounting of a bending arbor.

Fig. 5 is a small diagrammatic view illustrating the arrangement 01 the apparatus.

Fig. 6 is a view illustrating a modified form of arbor.

Fig. '1 is an end view of the modified form of arbor.

The apparatus advantageously comprises a suitable support or table having a top portion l and supporting legs 2, while other work supporting elements, as indicated at 3, may project from the table any requisite length for carrying the elongated stock, such as the tube, illustrated at T.

Mounted on the support is a post or anchoring member I. Adjacent the post I, and positioned above the same is a cam element 8 provided with an inclined or cammed surface 9 while an ad justable stop Ill is also located on the table adjacent the post I. A fixed arbor i2 is mounted on the support in a position spaced from the post 1 distances in two directions depending upon the size of coil made. A supplemental support I3 is provided and it may be adjacent the arbor l2 as shown.

Mounted on the table is a swinging arm l5, and this arm is mounted to swing about a pivot on an axis fixed relative to the arbor l2. The pivotal mounting for the arm I5 is illustrated at ii, the same being in the form of a stub shaft in a bearing IT. This shaft extends through the bearing, and on its end opposite the arm I5, is a counterweighted arm l8 for balancing purposes. In the normal rest position, the arm l5 may be supported by an adjustable stop 20. In a simple mechanism the arm I5 may be manipulated by hand and for this purpose it is provided with a handle 2| connected thereto by an arm 22.

The arm l5 carries a bending arbor 25, and this arbor is slidably mounted in the arm. To this end, there is a slide block 25 slidably mounted in an aperture 21 in the arm for which purpose the block comprises a. plate portion 26a attached to the portion 28, as by screws 28 so that the two portions overlap opposite sides of the arm and the block is thus retained in position. As shown in Fig. 4, the arbor 25 has a stud 3| which extends through the block 26-2611. and is provided on its opposite end with a roller 32. The stud 3i also holds a plate 30 in pivotally mounted position on the block.

A spring structure, which may embody one or more coil springs 35, has one end mounted in a recess 36 in the arm while its other and acts upon the block 26 to urge it to the right as Figs. 1 and 4 are viewed, normally against an adjustable stop 31.

The plate 30 carries a clamp structure for clamping the stock. This clamp structure, as shown in Figs. 1 and 3, includes a fixed clamping block 40 positioned immediately adjacent the arbor 25, but in advance thereof, and a movable clamping block it slidably mounted in a guide 3 l2 and which is arranged to be acted upon by a cam or eccentric 43 provided with an operating handle 44.

The apparatus may be employed to bend a single piece of stock or it may be used to bend a plurality oi pieces of stock red to the machine simultaneously. As illustrated in Figs. '2 and 3, two pieces of stock in the i'orm or tube are disposed in the machine. There is a tail piece II in the form of a long rod or bar which is attached to the plate 28 and it extends from the machine in the direction from which the stock is supplied and is guided by devices, such as rollers 48 and 49, in the support 3. As shown in Fig. 5, the support 3 is removed quite a distance from the work table. This bar, as will presently be seen, maintains the position of the plate 26 and takes the load oil the stock during the swinging action oi the arm II.

The arbors i2, and 25 are shown with smooth surfaces. However, grooved arbors may be used as shown in Figs. 6 and 7. The modified arbor 50 is shown for use with two pieces or stock, and is fashioned with a groove 8i and a groove 52. The side portions of the grooves are cut away at one or more points thus providing flats 53. The flattened ofi portion does not extend inwardly beyond the bottom of the grooves but merely removes the side portions thereof and this permits removal or the formed tube as will presently be seen.

In the operation or the machine, the several parts are normally in the full-line position shown in Fig. 1. At this time, the stock T may be advanced into the machine. It is threaded between the clamp elements I and 4|, passed over the arbor 25, under the arbor I2, and beyond the post I. To make the first bend at 1!, around the post I, the operator may merely bend the stock around the post by hand and may then place the end of the stock over the supplementary support l3 so that the stock is now held securely in position. The post I is of a size as to provide a bend which may be identical to bends formed by the mandrels. Making sure that the bend y is snug against the post 1, the stock is now clamped by manipulation of the cam 43. With the stock thus located and clamped in the machine, the handle is grasped and the arm I is swung on its rpivot iii in a counter-clockwise direction as Fig. 1 is viewed.

The resultant action is that of making two bends simultaneously. As the arm I5 is so rocked on its axis the stock is bent around the arbor I! as indicated. Also the stock is bent around the arbor 25 as indicated. Inasmuch as the stock is clamped in position so that there is no lengthwise movement or feeding action of the stock during the bending operation. the length of the stock between the center 01' the arbor l2 and the center oi! the arbor 25 must be such as to accommodate the length of stock required in two bends and two runs. By that we mean two of the bends y in the serpentine form with two adjacent runs a: (Fig. 1).

The operation at forming a bend around the arbor I2 is easily understood as the stock is merely wrapped around the same. As the arm is is swung on its axis, any fixed part of the arm swings on a true radius about the axis of the pivotal mounting IS. The curve z represents this function: the curve a is an are around the pivot I! on the radius of the center oi the arbor 25 when the arm I5 and arbor 25 are in the rest or starting position shown in Fig. 1. Howwhich time the roller 32 engages ever, as the swinging progresses through the dotted line positions shown. the position of the arbor 25 and clamp must change due to the fact that some of the lineal extent of the tube between the arbor I! and the clamp 40- is taken up in the bends. Accordingly. as the bending operation progresses, the block 28 is shifted in the slot I! against the action of the spring 35 as some 01' the stock is taken up in the wrapping action. Accordingly. the arbor 2| and the clam describe a form of involute curve 2'. This may be a compound invoiute curve generated by wrapping the stock about the two arbors l2 and It. The action keeps the stock taut. The plate It rocks on the axis or stud II of the arbor 2B in this action with the result that the clamp stays in line with the length of the stock which is clamped thereby.

As the arm it reaches the extreme position as shown to the left, as Fig. l is viewed, the two bends around the arbor l2 and the arbor 25 are completed and it is now necessary to remove the bends from the others. This is accomplished by pushing the arm in a downward direction at the inclined surface 9. This pushes the block 26 relative to the arm I 5 against the action of the spring 15 toward the arbor I2 to thereby shorten the center to center distance between the arbors so that the two bends may he slipped oi! the arbors. This is the purpose for providing the flats It on the modified arbor structures. shown in Figs. 5 and 6. The clamp is now released, the bends slipped oil the arbors, and the coil dropped downwardly so that the bend, which has Just been formed about the arbor 2!, may be placed over the post I and the run of tube immediately under the post hooked over the supplemental support IS. The arm is now swung clockwise to the full line position shown in Fig. 1, the stock again placed between the clamps. under the arbor l2 and over the arbor 2i and after the claim) has been applied the arm is swung counter-clockwise again to make two more bends. This completes one full cycle, and it will be seen how the formed serpentine coil grows downwardly, as indicated by the dotted lines shown in Fig. 1.

As will be appreciated by considering Fig. 1. the long length 01' stock is elevated from its support and has imparted thereto a swinging action as the arm I! is oscillated. In this action, the plate 30 and the clamp oscillate about the axis of the stud It and some forces must be overcome. This is the pu po e of the bar or rod ll which is attached to the plate 30. This bar, as shown in Fig. 5, is of considerable length and the stock and bar move together in this action. The bar takes whatever load there is in connection with the swinging oi the plate 3|] and the clamp, thus relieving the long length or stock of these forces.

The post I, as will be appreciated, performs no bending function in the operation or the machine other than the first bend which is manually made as above described, but is used as a convenient anchor. In other words, the stock must bt anchored on the down stream side oi the arbor II and since, after the first operation, a bend is available to: anchoring purposes, such bend is merely placed over the post I with the immediate underlying run disposed on the supplemental support II. This anchors the tube and prevents movement or the tube under the action of the spring II. The center to center distance between the arbor l2 and the arbor 25. as above mentioned, is progressively diminished during the bending operation as determined by the take-up in the stock incident to the stock being wrapped about the arbors. To provide a nlcety of action, the axis of the pivotal mounting It must be so located that all portions of the involute curve .2 lies within the arcuate curve .1, except in the fullline osition shown in Fig. 1 where the two curves may intersect. One factor in the location of the axis of the mounting ii is the radius of the bends formed. Inasmuch as the stock is supplied to the apparatus, from the right hand side as Fig. 1 is viewed, the anchoring post I may be considered as being downstream from the fixed arbor i2 and the clamp til-ll may be considered applicable to the stock upstream from the arbor 25. Such terminology is used in the claims appended hereto.

I claim:

1. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, a movable member mounted to move about the fixed arbor, a yieldably mounted arbor on said member, means for anchoring the stock on one side of the fixed arbor, a clamp on said member for clamping the stock on the side of the yieidably mounted arbor opposite the fixed arbor, said clamp being yieldably mounted for yieldabie shift in unison with the yieldably mounted arbor, and means for moving said member about the fixed arbor to bend the stock around the said two arbors with the arbor on the said member and the clamp shifting yieldably on the member to accommodate the take-up in the stock incident to the wrapping of the stock around the arbors.

2. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, a swinging member, a pivot for the swinging member, an arbor on the swinging member, a clamp on the swinging member, means yieldably mounting the second mentioned arbor and the clamp on the swinging member, means for anchoring the stock on one side of the fixed arbor, said clam being applicable to the stock on the side of the second mentioned arbor which is opposite that of the fixed arbor, and means for swinging the member on its pivot to bend the stock about both the said arbors,

3. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a, fixed arbor, a swinging member, a pivot for the swinging member, an arbor on the swinging member, a clamp on the swinging member, means yieldabiy mounting the second mentioned arbor and the clamp on the swinging member, means for anchoring the stock on one side of the fixed arbor, said clamp being applicable to the stock on the side of the second mentioned arbor which is opposite that of the fixed arbor, and means for swinging the member on its pivot to bend the stock about both the said arbors, the pivot for said swinging member being so located relative to the axis of the fixed arbor that the take-up in the stock, as it is formed about the arbors, shifts the yieldabie arbor and clamp on said swinging member.

4. An apparatus for shaping stock of elongated form, such as tube, two coils oi serpentine form having a succession of reverse bends, comprising a fixed arbor, a swinging member, a pivot for the swinging member, an arbor on the swin ing member, a clamp on the swinging member, means yieldably mounting the second mentioned arbor and the clamp on the swinging member, means for anchoring the stock on one side of the fixed arbor, said clamp being applicable to the stock on the side of the second mentioned arbor which is opposite that of the fixed arbor, and means for swinging the member on its pivot to bend the stock about both the said arbors, the pivot for said swinging member being so located relative to the axis of the fixed arbor that the take-up in the stock, as it is formed about the arbors, shifts the yieldabie arbor and clamp on said swinging member in a form of involute curve, all portions of which lie within a true are described by a point on said member which is concentric with the center oi' the yieldably mounted arbor before movement of the said member.

5. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm pivotally mounted on an axis adjacent the arbor, a support slidably and rockably carried by the arm, yieldabie means acting upon the support, an arbor carried by said support, a clamp carried by said support, said arbors adapted to have a substantially straight run of stock positioned adjacent and substantially tangent thereto, means for anchoring the stock on one side of the fixed arbor, the clamp being applicable to the stock adjacent the arbor on said support and on the side thereof opposite from the fixed arbor, means for swinging said arm about its pivot to cause the stock to be bent about both of said arbors, said yieldabie means affording movement of the support on said arm to accommodate for the take up of stock as the same is wrapped around the arbors, said support rocking on its mounting whereby the clamp remains in substantial alignment with the stock held thereby.

6. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm pivotally mounted on an axis adjacent the arbor, a support slidably carried by the arm, yieldabie means acting upon the support, an arbor carried by said support, a clamp carried by said support, said arbors adapted to have a substantially straight run of stock positioned adjacent and substantially tangent thereto, means for anchoring the stock on one side of the fixed arbor, the clamp being applicable to the stock adjacent the arbor on said support and on the side thereof opposite from the fixed arbor, means for swinging said arm about its pivot to cause the stock to be bent about both of said arbors, said yieldabie means affording movement of the support on said arm to accommodate for the take up oi. stock as the same is wrapped around the arbors, said clamp being rockable whereby the clamp remains in substantial alignment with the stock held thereby.

7. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm pivotally mounted on an axis adjacent the arbor, a support slidably carried by the arm, yieldable means acting upon the support, an arbor carried by said support, a clamp carried by said support, said arbors adapted to have a substantialLv straight run of stock positioned adjacent and substantially tangent thereto, means for anchoring the stock on one side of the fixed plicable to the stock afiording movement of the support on said arm to accommodate for the take up of stock as the same is wrapped around the arbors, said clamp being rockable whereby the clamp remains in substantial alignment with the stock held thereby, the pivotal mounting of said arm being so disposed relative to the fixed arbor that the take up in the tube causes the arbor on the arm to describe a form of involute curve substantially all portions of which are within a true are described on the radius of the arbor on the arm prior to the swinging movement of the arm.

8. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm, means pivotally mounting the arm adjacent the fixed arbor, an arbor on the arm, a clamp on the arm, means yieldably mounting the arbor and clamp for shift of the same relative to the arm, said arbors arranged so that a substantially straight piece 01' stock may be placed adjacent the same. means for anchoring the stock downstream from the fixed arbor, the clamp being applicable to the stock upstream from the yieldable arbor, means for swinging the arm about its pivot to cause the stock to be wrapped about the two arbors with the yieldable means providing for shift of the arbor on the arm to accommodate for the take up of the stock as the same is wrapped around the arbors, and means active upon the arbor on the arm substantially at the end of the swinging movement to shift the same toward the fixed arbor to thereby loosen the arbors in the bends for removal of the bent portions therefrom.

9. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm, means pivotally mounting the arm adjacent the fixed arbor, a stop upon which the arm may rest, a support slidably and rotatably mounted on the arm, yieldable means for yieldably resisting sliding movement of the support, an arbor carried by the support, a clamp carried by the support, the two arbors being so related that a substantially straight length of stock may be positioned adjacent the same with the arbors on opposite sides thereof, means for anchoring the stock downstream from the fixed arbor, the clamp being applicable to the stock upstream from the arbor on the arm, means fr swinging the arm to cause the stock to be bent about the two arbors with the support shifting against the yieldable means to accommodate for the take up of stock as it is bent about the arbors, and means active upon the support substantially at the end of the swinging movement of the arm to shift the support on the arm relative to the fixed arbor to thereby loosen the formed bends on the arbors so that the same may be removed therefrom.

10. An apparatus for shaping stock of elongated form, such as tube, into coils oi serpentine form having a succession of reverse bends, comprising a fixed arbor, an arm, means pivotally mounting the arm adjacent the fixed arbor, a stop upon which the arm may rest, a support slidably and rotatably mounted on the arm, yieldable means for yieldably resisting sliding movement or the support, an arbor carried by the support, a clamp carried bt the support, the two arbors being so related that a substantially straight length of stock may be positioned adjacent the same with the arbors on opposite sides thereof, means for anchoring the stock downstream from the fixed arbor, the clamp being applicable to the stock upstream from the arbor on the arm, means for swinging the arm to cause the stock to be bent about the two arbors with the support shifting against the yieldable means to accommodate for the take-up of stock as it is bent about the arbors, a projection on the support, and an inclined surface engageable by the projection substantially at the end of the swinging movement of the arm to shift the support on the arm toward the fixed arbor to thereby loosen the formed bends on the arbors for removal of the same therefrom.

11. An apparatus for shaping stock of elongated form, such as tube, into coils of serpentine form having a succession of reverse bends, comprising a fixed arbor, a pivotally mounted arm having its pivot adjacent the fixed arbor, an arbor and clamp unit slidably mounted on the arm, yieldable means acting upon the unit, a stop for determining the rest position of the arm, said arbors being so related that a substantially straight piece of stock may be positioned adjacent the arbors with the arbors on opposite sides of the stock, means for anchoring the stock downstream from the fixed arbor, said clamp being applicable to the stock upstream from the arbor on the arm, means for swinging the arm about its pivot to bend the stock about both arbors, the yielding means serving for movement of the arbor and clamp unit on the arm to accommodate the take-up of stock as the same is formed about the arbors, whereby said unit moves in a path having a form of an involute curve, and means for shifting the arbor and clamp unit substantially at the end of the movement of the arm for loosening the bends on the arbors whereby the same may be removed therefrom.

ARTHUR W. PAYNE.

REFERENCES CITED The following references are of record in the file oi this patent:

UNITED STATES PATENTS Number Name Date 1,901,244 Brown Aug. 22, 1911 1,125,241 Wilson Jan. 19, 1915 1,695,836 Witmer Dec. 18, 1928 1,791,620 Hibbard Feb. 10, 1931 2,086,736 Palmer July 13, 1937 2,331,294 Bank Oct. 12, 1943

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