US3831419A

US3831419A - Machine for transversely curving elongated panels

Info

Publication number: US3831419A
Application number: US00278211A
Authority: US
Inventors: G Leese; D Kennedy
Original assignee: Dominion Bridge Co Ltd
Current assignee: Dominion Bridge Co Ltd
Priority date: 1972-07-05
Filing date: 1972-08-07
Publication date: 1974-08-27
Anticipated expiration: 1991-08-27
Also published as: CA960950A

Abstract

A pair of elongated, rotatable torque members are mounted in juxtaposed relation on a frame and are provided with longitudinal channels to receive longitudinal edges of a panel which is to be transversely curved. Winch-actuated cables are connected to levers fixed to the torque members for partially rotating the same in opposite directions, so that a panel held in the channels becomes transversely curved. As this occurs, movable mounting of the torque members on the frame permits them to move closer together as an incidental function of a decreased transverse dimension of the curved panel. Other winch-actuated cables return the torque members to their initial position after the curved panel is removed therefrom. The torque members may be either parallel to produce half-cylinders or convergent/divergent to produce half-cones.

Description

United States Patent [191 Leese et a1.

[11] 3,831,419 Aug. 27, 1974 1 MACHINE FOR TRANSVERSELY CURVING ELONGATED PANELS [73] Assignee: Dominion Bridge Company Limited,

Quebec, Canada [22] Filed: Aug. 7, 1972 [21] App]. No.: 278,211

[30] Foreign Application Priority Data 3,575,031 4/1971 Gray 72/311 Primary Examiner-Charles W. Lanham Assistant Examiner-M. J Keenan Attorney, Agent, or Firm-Fetherstonhaugh & Co.

[57] ABSTRACT A pair of elongated, rotatable torque members are mounted in juxtaposed relation on a frame and are provided with longitudinal channels to receive longitudinal edges of a panel which is to be transversely curved. Winch-actuated cables are connected to levers fixed to the torque members for partially rotating the same in opposite directions, so that a panel held in the channels becomes transversely curved. As this occurs, movable mounting of the torque members on the frame permits them to move closer together as an incidental function of a decreased transverse dimension of the curved panel. Other winch-actuated cables return the torque members to their initial position after the curved panel is removed therefrom. The torque members may be either parallel to produce half-cylinders or convergent/divergent to produce half-cones.

16 Claims, 9 Drawing Figures MACHINE FOR TRANSVERSELY CURVING ELONGATED PANELS This invention relates to new and useful improvements in machines for transversely curving flat elongated panels into the shape of half-cylinders or halfcones, so that a pair of such half-cylinders or half-cones may subsequently be joined along their longitudinal edges into a full cylinder or a full cone for fabrication into pipes, lamp standards, masts and other like products.

Conventionally, curving of flat panels was accomplished on a press-brake having a knife blade cooperating with a V-block. The panel was marked off into a number of divisions along which it was subsequently bent by the press-brake so as to approximate the desired half-cylinder or half-cone shape. Actually, the resultant shape had several flat sides in angular relation rather than a smooth curvature, and the procedure of marking off the plate and adjusting it in the press-brake for several successive bends was very time-consuming and expensive.

Another conventional procedure for forming halfcylinders or half-cones on a press brake utilized matching convex and concave dies corresponding to the particular shape to be formed. This, of course required a new set of dies for each change in diameter, taper or plate thickness, and the cost of dies for a reasonably wide range of cylinders or cones was prohibitive.

Still another conventional procedure was by roll forming, which required radial lines to be marked on the plate and the rolling done in stages about consecutive axes. This procedure was slow due to material handling between the rolling stages and, in instances of cones, the length of cone produced was relatively short so that several short components had to be welded end to end in order to obtain a cone of a substantial length.

In an effort to overcome these disadvantages of conventional plate or panel curving procedures, machines were developed for curving panels by forcing their opposite side edges toward each other and thereby deforming them to the desired curvature. One example of such a machine appears in US. Pat. No. 3,004,584 issued Oct. I7, 1961 to H. O. Fuchs et al. While such machines eliminate the use of press-brakes, dies and rolls, and while they generally well perform their intended function, they nevertheless are quite complicated, expensive and difficult to operate in order to produce satisfactory results.

It is therefore, the principal object of the present invention to structurally, functionally and otherwise improve upon machines of the general type disclosed in the aforementioned patent. As such, the machine of the invention is simple in construction, economical to manufacture, easy to operate, capable of accommodating a wide range of panel thicknesses and cylinder or cone diameters with expeditious adjustment as to size and shape, and well adapted to produce work of good quality with material handling reduced to a minimum.

With the foregoing more important object and features in view and such other objects and features which may become apparent as this specification proceeds, the invention will be understood from the following description taken in conjunction with the accompanying drawings, in which like characters of reference designate like parts, and in which:

FIG. 1 is an end elevational view of the panel curving machine of the invention, showing the same in position of the panel prior to bending;

FIG. 2 is a view similar to FIG. 1 but showing the machine in position of the panel already bent;

FIG. 3 is a top plan view of the machine as shown in FIG. 1;

FIG. 4 is an enlarged sectional view taken substantially in the plane of the line 4-4 in FIG. 3;

FIG. 5 is an enlarged sectional view taken substantially in the plane of the line 55 in FIG. 3;

FIG. 6 is an enlarged fragmentary sectional detail, taken substantially in the plane of the line 6-6 in FIG. 3-

FIG. 7 is an enlarged sectional view of the torque members similar to FIG. 4, but showing the bending means off-set from the torque member centre line;

FIG. 8 is an enlarged sectional detail taken substantially in the plane of the line 88 in FIG. 3 but showing another modified embodiment of torque members; and

FIG. 9 is an enlarged sectional view of still another modified embodiment of the torque members.

Referring now to the accompanying drawings in detail, the machine of the invention is designated generally by the reference numeral 10 and is designed for transversely curving elongated panels into the shape of half-cylinders or half-cones.

The machine comprises a suitably constructed framework including a pair of spaced parallel horizontal rails 12 mounted on supports 13. Pairs of wheeled carriages 14 are movable toward and away from each other on the respective rails 12, one of these carriages being shown in detail in FIG. 5 from which it will be apparent that each carriage has a set of wheels 15 which ride along the associated rail 12. Each carriage also has bearings 16 for a vertical pivot pin 17 by which a bearing block 18 is mounted on the carriage for partial rotating movement in a horizontal plane. A pair of transversely spaced, juxtaposed tubular torque members 19 extend longitudinally between thee rails 12, the ends of these torque members being provided with trunnions 20 which are rotatably joumalled in the bearing blocks 18 on the pairs of carriages 14. Preferably, the trunnions 20 are long enough so that the torque members 19 are afforded a limited amount of axial movement by such movement of the trunnions in the bearing blocks. While in the plan view of FIG. 3 the two torque members 19 are shown as being parallel, it will be understood that they may also assume a mutually convergent/divergent relationship, by virtue of the pivot mounting 17 of the bearing blocks 18 on the carriages 14 and further by virtue of the slidable disposition of the trunnions 20 in the bearing blocks. It will be also appreciated that the two torque members 19 may move closer together or further apart by movement of the carriages 14 along the rails 12.

Each of the torque members 19 has secured to one side thereof a longitudinally extending channel 21 and when the torque members are in the position shown in FIGS. 1, 3 and 4, these channels on the two troque members oppose each other with their open sides. In this condition the channels 21 are in position to receive opposite side edges of an elongated, flat panel P which is to be curved. As shown in detail in FIG. 6 and also in FIG. 4, the channels 21 have upper flanges 21a which are spaced transversely further apart than their lower flanges 21b, so that when the panel P is being applied to the machine, as from an above position indicated by the dotted lines P in FIG. 4, it may be lowered past the upper flanges 21a so as to come to rest on the lower flanges 2117. This avoids the necessity of inserting the panel longitudinally into the channels. The space 21c between the flanges 21a, 21b of the channels is sufficient to accommodate the thickness of the panel to be curved, plus any variation such as inherent out-of-plane waviness of the panel edges.

lnner stop blocks 22 are adjustably positioned on the rails 12 to limit the extent to which the carriages 14 and consequently the torque members 19 may move toward each other. Similarly, outer stop blocks 23 on the rails limit the extent to which the carriages and the torque members may move apart. Like the blocks 22, the blocks 23 are adjustable on the rails 12, and a measuring tape 24 is provided on each rail so that the stop blocks may be placed at equal distances at opposite sides of the center line 25 of the machine.

A pair of actuating levers 26 are rigidly secured to the end portions of each torque member 19 and as will be apparent from FIG. 3, the levers on each torque member are offset from those on the other torque member to avoid interference with each other. The levers 26 are double-arm levers, extending both above and below the torque members. The upper ends of the levers carry rotatable pulleys 27 and their lower ends carry rotatable pulleys 28. The machine framework also includes a pair of open rectangular frame members 29 which are disposed inwardly of the rails 12, each frame member 29 being located so that the levers 26 on the associated end portions of the torque members 19 are disposed in planes at the opposite sides of the frame member, as will be apparent from FIG. 3. In other words, each frame member is disposed in a plane between the offset pair of levers.

Each frame member 29 has a set of

pulleys

30, 31 and 32 mounted on each side thereof. Pairs of cables 33 are anchored to the frame members 29 as at 34, the cables passing successively around the pulleys 27 at the top of the levers 26, around the

pulleys

30, 31 and 32 on the frame members, around pulleys 28 at the bottom of the levers, and ultimately extending to a common pulling source as indicated at 35. The pulling source may be a suitable winch which is not shown in the drawings.

lt will be apparent from the foregoing that when the machine is in the position shown in F 16. l and a pulling force is applied to the cables 33, the

levers

26, 26 will be rotated about the axes of the torque members 19 in relatively opposite directions to the position shown in F IG. 2. The torque members, of course, will rotate with the levers, and the panel P with its side edges placed in the channels 21 on the torque members will be bent from the flat form shown in FIG. 1 to the curved form shown in F IG. 2. As the transverse dimension of the curving panel decreases, the torque members 19 will automatically move closer together while the carriages 14 move toward each other along the rails 12.

Means are provided for moving the torque members 19 apart from each other to their initial position after the curved panel has been removed from the machine. These means comprise an auxiliary winch 36 on the machine frame, having a drum 37 with cables 38 windable in opposite directions on the drum. The cables 38 pass around guide pulleys 39, 40 on the frame and are windable around diametrically reduced portions 41 of the torque members 19, adjacent the carriages 14.

For a purpose hereinafter described, the outer stop blocks 23 at one side of the machine are provided with power cylinders 42 which have projectable pistons engageable with the carriages 14 on that side of the machine for moving these carriages inwardly by a small distance along the rails 12, away from the stop blocks 23.

In operation, the machine is in its initial position as shown in FIG. 1, with the carriages l4 moved apart against the outer stop blocks 23 on the rails 12, these stop blocks having been adjusted so that the torque members 19 are spaced apart by a distance for reception of the panel P in the torque member channels 21 as shown in FIG. 4. The panel, which has been picked up by suction, magnet, or the like, is placed centrally over the machine as indicated at P in FIG. 4 and is then lowered so that its side edges rest on the lower flanges 21b of the channels 21. The power cylinders 42 on the outer stop blocks 23 at one side of the machine are then energized so that their pistons push the carriages 14 on that side of the machine inwardly by a short distance from the blocks 23, and this causes the side edges of the panel P to become fully seated within the channels 21.

With the auxiliary winch 36 disengaged, the main actuating winch of the machine is energized to exert a pulling force on the cables 33. This causes rotation of the levers 26 and torque members 19 as already described, so that the panel P held by its side edges in the channels 21 becomes bent from its initial flat form to a semicircular, transversely curved form as shown in FlG. 2. With the decreasing transverse dimension of the curving panel, the torque members 19 automatically move closer together as the carriages 14 move together along the rails 12, until the carriages abut the inner stop blocks 22. These stop blocks are prepositioned on the rails 12 to facilitate a certain amount of over-bending of the panel and spring-back thereof to the desired form when the bending forces are discontinued.

At the completion of the bending operation the main winch actuating the cables 33 is disengaged, and this causes relaxation of the cables so that the curved panel may spring back to its final form. At this stage, the torque member channels 21 are oriented upwardly as in FIG. 2, and since the curved panel is no longer under stress, it can be readily removed by lifting the same from the machine.

The auxiliary winch 36 is now engaged and the pistons of the power cylinders 42 are retracted. Winding of the cables 38 on the winch drum 37 will rotate the levers 26 from the position of F IG. 2 to their initial position shown in HO. 1, while the cables 33 are drawn freely from the main winch. Simultaneously, the torque members 19 will be rotated by the levers 26 to their initial position wherein the channels 21 horizontally oppose each other, and at the same time, the carriages 14 will be moved apart along the rails 12 to the initial, spaced apart position of the torque members, where the carriages come up against the outer stop blocks 23. The machine will then be ready for the next cycle of operation.

When the panel P is to be curved into a half-cylinder form, the torque members 19 are mutually parallel and so remain throughout the bending operation. However,

if the panel is sector-shaped and is to be curved into the form of a half-cone, then the outer stop members 23 are set so that the torque members are mutually divergent or convergent, and the inner stop members 22 are also set so that the desired tapered curvature of the panel is produced. In this connection it is to be noted that the vertical pivots 17 of the bearing blocks 18 on the carriages l4 permit the torque members 19 to assume either a mutually parallel or a convergent/divergent relationship in both the initial and final stages of the bending procedure, in addition to compensating for different rates of travel of the carriages at the opposite ends of the panel when half-cones are being formed.

If the diameter of the half-cylinder or half-cone to be formed is relatively small, it may be necessary to offset the channels on the torque members so that they are somewhat tangential rather than radial, as indicated in the modified embodiment of FIG. 7. In the event that it is not practical to provide the channels 21 on the torque members 19 of a cylindrical cross-section, the torque members may have another cross-sectional form, as for example that of a rectangle, as shown at 19a in FIG. 8.

FIG. 9 illustrates another modified embodiment in which a panel may be bent into a U-shaped crosssection, with a semi-circular bight portion P-a and flat, parallel leg portions P-b. In this instance the rectangular torque members 19a are provided with bending members 45 having slots 46 which receive the flat side or leg portions P-b of the panel and torque is applies to form the curved bight portion P-a at the outside of the bending members. The dimension 47 of the flat leg portions P-b may be preset by inserting filler blocks 48 into the slots 46, or by providing adjustable stop screws as indicated at 49. While in the foregoing there have been described and shown the preferred embodiments of the invention, various modifications and equivalents may be resorted to, within the spirit and scope of the invention as claimed.

The embodiments of the invention in which an exclusive property or privelege is claimed are defined as follows:

1. In a machine for transversely curving flat panels, the combination of, a support frame, a pair of elongated and rotatable torque members, means for mounting said torque members on said frame in spaced juxtaposed relation to each other for rotation about their axes and also for transverse movement towards and away from each other, each torque member having a longitudinal channel extending therealong and being of sufficient length to receive the entire edge of the panel to be curved, whereby the two opposite edges of the panel to be curved are received along their complete lengths, one in each of said channels, and actuating means for turning said torque members in relatively opposite directions and concurrently moving the torque members toward each other as a function of the decreased transverse dimension of the curved panel to transversely curve the panel engaged by the said channel, said actuating means including levers rigidly secured to the torque members, and means reacting between said frame and said levers for moving the latter.

2. The machine as defined in claim 1 together with means on said frame for moving said torque members transversely apart to their initial position after a curved panel has been removed from said channels.

3. The machine as defined in claim 1 together with stop means on said frame for limiting movement of said torque members toward each other.

4. The machine as defined in claim 1 together with stop means on said frame for limiting movement of said torque members apart from each other.

5. The machine as defined in claim 1 wherein said frame includes transverse rails adjacent the ends of said torque members, together with carriages movable toward and away from each other on said rails, and bearing blocks provided on said carriages, the ends of said torque members being rotatably joumalled in said bearing blocks.

6. The machine as defined in claim 5 which is further characterized in that said torque members are axially slidable within limits in said bearing blocks.

7. The machine as defined in claim 5 together with pivots mounting said bearing blocks on said carriages for movement about axes normal to said torque members, whereby the torque members may selectively assume a mutually parallel and a mutually convergent/divergent relationship.

8. The machine as defined in claim 1 wherein said actuating means include levers rigidly secured to the torque members, and means reacting between said frame and said levers for moving the latter.

9. The machine as defined in claim 1 wherein said last mentioned means include winch-actuated cables connected to said levers.

10. A machine for transversely curving elongated flat panels, comprising in combination an elongated supporting frame including separate transversely extending rails at each end of the frame, pairs of carriages movable on each said rail transversely toward and away from each other, a pair of elongated torque members, each extending longitudinally of the frame between said rails and rotatably mounted at each end in one of said carriages, whereby each torque member is rotatable about its axis and also movable transversely towards the other torque member upon transverse movement of its respective carriages, said torque members being provided with longitudinally extending channels of sufficient length to receive the entire length of opposite longitudinal edges of a panel to be curved, levers rigidly secured to opposite end portions of said torque members, winch-actuated cables reacting between said frame and said levers to partially rotate the torque members in relatively opposite directions and concurrently move the torque members with said carriages incidentally toward each other as a function of a decreased transverse dimension of the curved panel, and means on said frame for moving said torque memers with said carriages apart to their initial position after a curved panel has been removed from said channels.-

11. The machine defined in claim 10 together with bearing blocks having the ends of said torque members rotatably joumalled therein, and pivots mounting said bearing blocks on said carriages for movement about axes normal to the torque members, whereby the latter may selectively assume a mutually parallel and a mutually convergent/divergent relationship.

12. The machine as defined in claim 1 1 together with stop means adjustable on said rails for limiting movement of said carriages toward each other.

13. The machine as defined in claim 11 together with stop means adjustable on said rails for limiting movement of said carriages apart from each other.

14. The machine as defined in claim which is further characterized in that said channels on said torque members are transversely oppsed when the torque members are rotated to a position for receiving edges of a flat panel, the channels in that position having vertically spaced upper and lower flanges with the transverse spacing of the upper flanges being greater than that of the lower flanges so that a panel may be passed downwardly between the upper flanges to rest on the lower flanges of the channels.

15. The machine as defined in claim 14 together with means reacting between said frame and the carriages of one of said torque members for initially moving the same toward the other torque member whereby to seat the panel edges in said channels.

16. The machine as defined in claim 10 wherein said means for moving said carriages apart after a curved panel has been removed from said channels includes means for rotating said torque members to their initial position.

Claims

5. The machine as defined in claim 1 wherein said frame includes transverse rails adjacent the ends of said torque members, together with carriages movable toward and away from each other on said rails, and bearing blocks provided on said carriages, the ends of said torque members being rotatably journalled in said bearing blocks.

10. A machine for transversely curving elongated flat panels, comprising in combination an elongated supporting frame including separate transversely extending rails at each end of the frame, pairs of carriages movable on each said rail transversely toward and away from each other, a pair of elongated torque members, each extending longitudinally of the frame between said rails and rotatably mounted at each end in one of said carriages, whereby each torque member is rotatable about its axis and also movable transversely towards the other torque member upon transverse movement of its respective carriages, said torque members being provided with longitudinally extending channels of sufficient length to receive the entire length of opposite longitudinal edges of a panel to be curved, levers rigidly secured to opposite end portions of said torque members, winch-actuated cables reacting between said frame and said levers to partially rotate the torque members in relatively opposite directions and concurrently move the torque members with said carriages incidentally toward each other as a function of a decreased transverse dimension of the curved panel, and means on said frame for moving said torque memers with said carriages apart to their initial position after a curved panel has been removed from said channels.

11. The machine defined in claim 10 together with bearing blocks having the ends of said torque members rotatably journalled therein, and pivots mounting said bearing blocks on said carriages for movement about axes normal to the torque members, whereby the latter may selectively assume a mutually parallel and a mutually convergent/divergent relationship.

12. The machine as defined in claim 11 together with stop means adjustable on said rails for limiting movement of said carriages toward each other.

14. The machine as defined in claim 10 which is further characterized in that said channels on said torque members are transversely oppsed when the torque members are rotated to a position for receiving edges of a flat panel, the channels in that position having vertically spaced upper and lower flanges with the transverse spacing of the upper flanges being greater than that of the lower flanges so that a panel may be passed downwardly between the upper flanges to rest on the lower flanges of the channels.