US3009201A

US3009201A - Material bending machine with roll bar

Info

Publication number: US3009201A
Application number: US849678A
Authority: US
Inventors: George F Hansen
Original assignee: FAWN FABRICATORS Inc
Current assignee: FAWN FABRICATORS Inc
Priority date: 1959-10-29
Filing date: 1959-10-29
Publication date: 1961-11-21
Anticipated expiration: 1978-11-21

Description

Nov. 21, 1961 Filed Oct. 29, 1959 G. F. HANSEN MATERIAL BENDING MACHINE WITH ROLL BAR 3 Sheets-Sheet 1 N Geo/ye [Ta/Z5672,

Nov. 21, 1961 cs. F. HANSEN 3,009,201

MATERIAL BENDING MACHINE WITH ROLL BAR I Filed Oct. 29, 1959 3 Sheets-Sheet 2 Nov. 21, 1961 G. F. HANSEN MATERIAL BENDING MACHINE WITH ROLL BAR Filed Oct. 29, 1959 if 75 16 p 45 62 4 7i 6 47\Q o 5 7 1 '75 50 @5 W I ix a 5 Sheet-Sheet S IN V EN TOR. flea/g6 Uawen, BY

MATERIAL BENDING MACHNE WI] H ROLL BAR George F. Hansen, Elgin, Ill., assignor to Fawn Fabricators Inc., Elgin, Ill., a corporation of Illinois Filed Oct. 29, 1959, Ser. No. 849,678 Claims. (CI. 18-19) The invention relates to material bending apparatus and has reference more particularly to apparatus for bending thermoplastic sheet material over rounded and formed edges of backing members and wherein the arcuate contour of the bend may vary in r-adii over a considerable range.

The bending machine of the invention is ruggedly constructed according to all engineering requirements to thereby permit day-in and day-out repetitive use. Another object of the invention resides in the provision of a novel and improved bending machine which will perform its bending functions in a single and continuous operation so that preforming of the sheet material is eliminated.

Another object of the invention is to provide a bending machine of the type described which will employ one or more power cylinders for actuating a presser foot for applying pressure to the plastic material adjacent the edge to be bent, the said power cylinder thereafter actuating a roll bar device for effecting the bending of the material around the formed and arcuate edge of the backing member.

A further object is to provide a machine for bending thermoplastic material which will incorporate an improved movable roll bar device for bending the material in a manner as described and wherein said roll bar device will be constructed so as to operate in such a manner as to compensate for varying and different thicknesses of said material and for variations in the size of the formed and arcuate edge of the backing member.

Another and more specific object of the invention resides in the provision of a new and novel roll bar device which will bend the edge of the plastic material around and under the formed and arcuate edge portion of the backing member, thereby effecting a one hundred and eighty degree wrap around bend in the material.

Another object is to provide a bending machine which will be eflicient in operation, relatively simple in construction and which can be economically manufactured.

With these and other objects in view, the invention may consist of certain novel features of construction and operation, as will be more fully described and particularly pointed out in the specification, drawings and claims appended hereto.

In the drawings which illustrate an embodiment of the device and wherein like reference characters are used to designate like parts- FIGURE 1 is a front elevational view illustrating the improved material bending machine of the invention;

FIGURE 2 is an elevational view of the left end of the bending machine as shown in FIGURE 1;

FIGURE 3 is a fragmentary vertical sectional view showing the presser foot in pressure contact with a thermoplastic sheet and illustrating the mode of operation of the roll bar device for bending the edge of the sheet; and,

FIGURE 4 is a fragmentary vertical sectional view similar to FIGURE 3 but illustrating a full wrap around position of the roll bar device;

Referring more particularly to the drawings which disclose a preferred embodiment of the invention, the numeral 10, FIGURE 1, indicates the supporting frame of the machine and which essentially consists of side frame supports 11 and 12, -a longitudinal top frame member "14 and a longitudinal intermediate frame member 15.

The top and intermediate frame members extend horithe intermediate frame member 15.

3,009,201 Patented Nov. 21,, 1961 zontally and connect with the side frame supports. The frame of the present machine also includes a horizontally extending table 16, FIGURE 2, which also extends between and connects with the side frame supports 11 and 12. The table 16 is located below the intermediate frame member 15 having a position approximately midway of the frame and the said table provides a flat surface for supporting the backing member 17 and the material 18 to be processed. Along the rear edge of the table 16 there is located a stop member such as 20 and the said table along its front edge is provided with a forwardly extending flange 21. The flange 21 receives and positions the formed and arcuate edge portion 22 of the backing member 17. The thermoplastic sheet material 18 is adapted to be adhesively secured to the backing member 17, and the numeral 23 indicates the edge of the thermoplastic sheet which is to be bent by the machine of the invention to form a full wrap around covering 24, FIGURE 4, for the formed and arcuate edge portion 22.

The presser foot and roll bar device which constitute the main elements of the present bending apparatus are suspended from an upper channel member 25 which extends horizontally between and is supported by the side frame supports 11 and 12. The upper channel member 25 at its respective ends is mounted on the side frame supports in a manner permitting movement vertically to and from an operative and inoperative position. For this purpose the ends of the upper channel member are provided with

mounting plates

26 and 27, FIGURE 1, respectively, each plate carrying a plurality of rollers 28. Plate 26 is fixed to the left hand end of the member 25 and is located adjacent the outside surface of the side frame support 11. The rollers 28 are positioned to have rolling contact with the front and rear edges of the frame support. In a similar manner plate 27 is fixed to the right hand end of the upper channel member 25 and said plate is adjacent the outside surface of the side frame support 12, having the rollers 28 which roll on the front and rear edges of the said support. Accordingly, the upper channel member is adapted to reciprocate on the side frame supports from an upper inoperative position as shown in FIGURE 3, to a lower operative position as shown in FIGURE 4.

The reciprocating movement of the member 25 is effected by power cylinders 30 which are supported by the top and intermediate frame members. One or more power cylinders may be located on respective sides of the center of the machine, depending on the size of the machine and the power required for the bending operation. Bracket 31, as best shown in FIGURE 2, assists in mounting the top end of each power cylinder to the top frame member 14, whereas bracket 32 assists in supporting the lower end of the power cylinders from The piston rod such as 33 of each power cylinder is suitably connected to the clevis 34 which, in turn, is pivoted to bracket 35 bolted to the top flange of the upper channel member 25. When the power cylinders 30* are energized to move their piston in a downward direction, their respective piston rods 33 move the channel member 25 in a downward direction, thus moving the member from its inoperative position as shown in FIGURE 3, to its operative position as shown in FIGURE 4.

A plurality of push rods are suspended by the upper channel member, the said rods being designated by the numeral 36. Each push rod extends through the flanges of the said upper member. For example, as best shown in FIGURE 3, the push rods 36 extend through the lower flange 37 of the member 25 and through the upper flange 38 of the upper channel member. The push rods 36 also extend above their bearing 41 to receive a pin 42 which determines the normal position of the push rods. The said normal position of each push rod is yieldingly maintained by the tension spring 43, the said spring being helical and having a surrounding relation with its respective push rod. It will be understood that the top end of the coil spring 43 is adapted to have contact with the undersurface of top flange 38, whereas the lower end of each spring 43 is adapted to contact a pin 44 carried by the push rod and normally located immediately above the lower flange 37. The expanded tension of spring 43 is thus applied to its push rod through the pin 44, and accordingly, each push rod is normally urged in a downward direction. The

pins

42 and 44 act as stops, since they function to limit movement of the push rods in a direction downwardly as yieldingly urged by the respective coil springs.

A lower channel member indicated by numeral 45 is suitably fixed to the lower depending end of the push rods 36. Again, referring to FIGURE 3, it will be seen that each push rod 36 extends through the top flange 46 of the channel member 45 and has abutting contact with the lower flange 47. A securing screw may be employed to connect each push rod to the flange 47, or the said push rods may be welded to said flange. In either case the lower channel member 45 is fixedly secured in a predetermined position to the push rods and reciprocating movement of the said rods as caused by movement of the upper channel member will, accordingly, be imparted to the lower channel member. A shoe plate such as 48 may be secured to the undersurface of the flange 47 as by the screw and wing nut 49 and a resilient presser foot 50, preferably formed of rubber, is suitably secured to the undersurface of the shoe plate. It is desirable to form the presser foot 50 of rubber or other suitable resilient material, since the presser foot is adapted to contact the surface of the thermoplastic sheet material 18 for applying pressure thereto so as to hold the sheet in firm and secure contact with the backing member at a location adjacent the formed and rolled edge of said member.

In accordance with the invention the roll bar device is actuated by the conjoint action of the upper channel member and the lower channel member. The said roll bar device, generally indicated by numeral 52, is suspended from the upper channel member by the hangers 53. The upper end of each hanger is pivotally secured as at 54 to bracket 55 secured to the top flange 38 of member 25 by the securing bolts 56. The channel member 57 which constitutes one of the elements of the roll bar device provides a top flange 58 and a lower flange 60*. Brackets 61 are secured to the top flange 58 by securing bolts such as 62, and each bracket is pivotally connected as at 63 with the lower depending end of a hanger 53. The center web of the channel member-57 is provided with a plurality of brackets 64, each bracket being secured to the channel member 57 by securing bolts such as 65. The arms 66 of the roll bar are pivoted at 67 to the brackets 64, and thus the arms are carried by the channel member 57 in a manner to permit rotation of the arms about pivot axis 67. By means of the flat tensioning springs 68, the arms are yieldingly biased in a clockwise direction, and the numeral 70 indicates an adjustable stop so that the arms 66 are normally held in a predetermined position by the tension exerted by the flat springs 68. It is understood that a plurality of arms 66 will be carried by the channel member 57 and the said arms are suitably connected by a shaft such as 71 which journals the rollers 72. The rollers 72, accordingly, extend the length of the machine from adjacent side frame 11 to adjacent side frame 12, and upon actuation of the roll bar device the rollers are caused to contact the projecting edge 23 of the thermoplastic sheet material and effect a wrap around bend of the edge with respect to the formed and arcuate edge portion 22.

For controlling the rolling and bending movement of the arms 66 the channel member 57 which carries the said arms is pivotally connected to the lower channel member 45. The said pivotal connection of channel member 57 to channel member 45 is effected by the strap hinge 73, the said strap hinge having a leg 74 which is secured to the inside surface of flange 47 of the lower channel member 45 as by welding or other convenient means. The said strap hinge is also provided with a second leg 75 which is similarly secured to the top flange 58 of the channel member 57.

The first step in the bending operation is to heat the overhanging edge 23 of the thermoplastic sheet in order to soften the same and facilitate the bending of the overhanging edge. This heating step is accomplished by the heaters which are suitably secured at 81 to the supporting arms 82. The said arms are pivotally supported at 83 by means of one or more brackets 84 and which are suitably secured to the underside of frame member 15. The inoperative position of the heaters 80 is shown in FIGURE 2 in full lines, with the operative position of the heaters being shown in dotted lines. For swinging the supporting arms 82 so as to move the heaters to and from operative and inoperative positions, a power cylinder 85 is provided, the piston rod 86 of which is secured to the clevis 87. The clevis is, in turn, pivoted at 88 to bracket 90 suitably fixed to its respective supporting arm 82. It is only necessary to energize the power cylinder 85 to cause its piston rod to project, whereby the heaters 80 are moved into their operative position directly over the projecting edge 23 of the thermoplastic sheet. To terminate the heating operation the heaters are withdrawn by a retraction of the piston rod within the power cylinder.

During the heating operation the presser foot 50 and the roll bar device 52 remain in an elevated inoperative position. However, immediately following the heating operation the power cylinders 30 are energized to move the channel member 25 in a downward direction. Similar movement is accordingly etfected of the push rods 36 and the channel member 45. Eventually the resilient presser foot 50 will be caused to contact the thermoplastic sheet 18' and thereafter downward movement of channel member 25 will produce a pivoting action of the roll bar device 52 in a clockwise direction. It will be understood that downward movement of channel member 25, after the presser foot 50 has contacted the thermoplastic sheet, will take place against the tension of springs 43, and, accordingly, the said springs 43 are compressed.

The pivoting action of the roll bar device as referred to will bring the roll bar 72 into contact with the projecting edge 23 and the said edge will be rolled around the portion 22 of the backing member. A full wrap around of the projecting edge is effected as shown in FIGURE 4 by the action of the arms 66 of the roll bar device. The channel member 57 in addition to supporting the arms 66 has the further utility of contacting the formed edge approximately intermediate the top and bottom surfaces and the pressure applied by the channel member 57 additionally assists in the formation of a wrap around bend which is firmly and adhesively secured to the edge portion of the backing member.

When the roll bar 72 is caused to initially contact the projecting edge 23 of the thermoplastic sheet, the position of the roll bar device is such as to force the arms 66 in a clockwise direction and thus the stop 70 is caused to contact the undersurface of flange 60. However, toward completion of the wrap around bend, the position of the roll bar device with respect to the formed and arcuate bend is such as to cause rotation of the arms 66 in a counterclockwise direction, at least with respect to the channel 57. It will be observed that this is provided for by the pivotal connection of the arms 66 at 67 and by the resilient tension which is applied to the arms by the flat spring 68. Accordingly, the roll bar device will automatically compensate for variations in thickness as regards the thermoplastic sheet and also variations in the size and contour of the arcuate edge portion 22 of the backing member. Thus, during the bending operation the roll bar device will pivot as a unit with respect to channel member 45 as provided by the strap hinge 73 and additionally the arms 66 will pivot with respect to their pivot axis 67. Also, it will be observed that the several steps in the bending operation take place sequentially, since the presser foot 50 is first caused to contact the thermoplastic sheet, and since channel 45 is thereupon held stationary, continued downward movement of channel member 25 will effect the desired pivoting action of the roll bar device. At the completion of the bending operation the channel member 25 is moved in an upward direction and the first result of this movement is to cause pivotal movement of the roll bar device in a counterclockwise direction about axis 73. Continued upward movement of channel '25 will eventually withdraw the presser foot 50, whereupon the parts will be again located in their elevated inoperative position as shown in FIG- URE 2.

This invention is not to be limited to or by details of construction of the particular embodiment thereof illustrated by the drawings, as various other forms of the device will, of course, be apparent to those skilled in the art without departing from the spirit of the invention or the scope of the claims.

What is claimed is:

1. In material bending apparatus, in combination, supporting frame structure providing a Work supporting member, a presser foot mounted for movement to and from the work supporting member, a roll bar device including a supporting member, a roll bar and arms pivotally connecting the roll bar with the supporting member, resilient means fixed to the supporting member and engaging the anms for yieldingly maintaining the said arms and roll bar in a predetermined position with relation to the supporting member, hinge means pivotally connecting the supporting member with the presser foot, and power means for sequentially effecting down-ward movement of the presser foot for contact with a workpiece on the work supporting member and pivotal movement of the roll bar device to cause the roll bar to perform a bending operation, and which will thereafter sequentially eflt'ect pivotal movement of the roll bar device in a reverse direction followed by upward movement of the presser foot to its initial location, said resilient means automatically compensating for variations in the size and thickness of the workpiece as encountered by the roll bar during the bending operation.

2. In material bending apparatus, in combination, supporting frame structure providing a work supporting member, an upper channel member mounted on said frame structure for reciprocating movement toward and from the work supporting member, a plurality of push rods suspended from the upper channel member, resilient means associated with the member and with each push rod for yieldingly maintaining the push rods in maximum extended position, a lower channel member fixed to the extended ends of the push rods, a presser foot provided by the lower channel member, a roll bar device including a supporting member and a roll bar having a pivotal connection with the supporting member, hinge means pivotally connecting the supporting member with the lower channel member, connections between the upper channel member and the supporting member of the roll bar device, and power means for reciprocating the upper channel member.

3. In material bending. apparatus as defined by claim 2, additionally including a plurality of arms for pivotally connecting the roll bar to the supporting member, and resilient means fixed to the supporting member and contacting the arms for yieldingly biasing the arms into a predetermined position.

4. In material bending apparatus, in combination, supporting frame structure providing a work supporting member, an upper channel member mounted on said frame structure for reciprocating movement toward and from the work supporting member, a plurality of push rods suspended from the upper channel member and extending a distance below the said member, resilient means associated with the member and with each push rod for yieldingly maintaining the push rods in maximum extended position, a lower channel member fixed to the extended ends of the push rods, a resilient presser foot provided by the lower channel member, a roll bar device including a supporting member, a roll bar and a plurality of arms for pivotally connecting the roll bar with the supporting member, hinge means pivotally connecting the supporting member with the lower channel member, hangers having pivotal connection at respective ends with the upper channel member and the supporting member, and power means for reciprocating the upper channel member.

5. In material bending apparatus as defined by claim 4, additionally including resilient means fixed to the supporting member and contacting the arms for yieldingly biasing the arms into a predetermined position, and an adjustable stop associated with the arms for adjusting said predetermined position.

References Cited in the file of this patent UNITED STATES PATENTS 2,252,491 Cloyd Aug. 12, 1941 2,288,273 Enghauser June 30, 1942 2,552,616 Bath May 15, 1951 2,866,493 Kovalcik Dec. 30, 1953 2,937,689 Peterson May 24, 1960