Method Of Bonding Sheets

Abstract

A mechanical splice for rolls of metal in continuous metal fabrication wherein each splice includes a portion deformed from adjacent sheets of metal thereby limiting relative movement therebetween. In one embodiment, the portion of material deformed is spread after it is deformed to prevent it from returning to its original condition. A die for performing the deformation and spreading includes a flat die surface with oppositely outwardly flaring end surfaces which press superimposed portions of the sheets of metal into a depression in a second die against a yieldable pin which spreads at least one of the portions by at least the time the movable die has bottomed out but after the one portion is deformed out of its sheet of material. The method of forming the mechanical splicing involves the deforming of the elongated portion thereby forming an opening in the sheet of material and then the spreading of the deformed portion such that it cannot pass back into the opening. The spreading may begin at the same time as the deforming step begins but is not completed until the deforming step has been completely finished. A second embodiment of the splicing includes semielliptical portions the mirror image of each other on opposite sides of a perpendicular plane to the sheets of material being deformed on opposite sides of a parallel plane to the sheets of material to lock the sheets against relative movement. The dies for forming the semielliptical deformations are the mirror image of each other and have convex outer surfaces whereby they register with each other.

Parent Case Text

This Application is a continuation of application Ser. No. 629,505, filed Apr. 10, 1967, now abandoned.

Description

In working with rolls of metal sheets or the like it is necessary from time to time to secure adjacent sheets together and thus the mechanical splices of this invention have been provided to accomplish this fastening by the use of a simplified machine and method. A die assembly may have a plurality of die elements for forming a plurality of splices between sheets in mating engagement with each other. In the one embodiment of the mechanical splice, elongated portions of material are deformed from their respective sheets thereby forming openings in the sheets and at least one of the elongated portions is then spread such that it cannot pass back into its opening in its sheet. These steps are performed in the method of making the splice of this invention by use of as for example the die machine of this invention. The second embodiment of the mechanical splice involves superimposed sheets each having side by side semielliptical deformed portions which are the mirror image of each other deformed in opposite directions perpendicular to the plane of sheets such that each side of the bonded sheets will include side by side concave and convex portions semielliptical in shape meeting along with minor axis.

These and other features and advantages of this invention will become readily apparent to those skilled in the art upon reference to the following description when taken into consideration with the accompanying drawings, wherein:

FIG. 1 is a fragmentary perspective plan view of a pair of rolls of sheet material having portions fastened together with a plurality of splices;

FIG. 2 is a fragmentary enlarged perspective view of the male die head;

FIG. 3 is a plan view of the female die head;

FIG. 4 is a fragmentary cross-sectional view of the die in its open condition;

FIG. 5 is a fragmentary cross-sectional view similar to FIG. 4 but showing the die and the material after the splice has been formed and the die has been returned to its open position;

FIG. 6 is a cross-sectional view taken along line 6 -6 in FIG. 5;

FIG. 7 is a fragmentary bottom plan view of the splice deformed by the die;

FIG. 8 is a top plan view of a pair of rolls of sheets material including a plurality of alternate mechanical splices;

FIG. 9 is a fragmentary perspective view of the two die halves for forming the alternate mechanical splice; and

FIG. 10 is a cross-sectional view of the dies and splice material with the die halves in their open condition.

In FIG. 1 two sheets of material 10 and 12 are shown being dispensed from a pair of rolls 14 and 16 respectively. A plurality of splices 20 have been formed between the two sheets of material 10 and 12.

A die press 24 includes a movable upper die half 26 and a stationary lower die half 27. The upper die half includes an elongated male element 28 having a center horizontal surface 30 with oppositely extending outwardly flaring flat surfaces 32 and 34. The bottom die half includes a cavity 36 substantially the same width and length as the male die element 28. A cylindrical plunger 38 larger in diameter than the cavity 36 (FIG. 3) is mounted in the center of cavity 36 and includes a truncated conical pin 40 in the center thereof. The cylindrical element 38 is movable within cavity 36 of the die half head 28 and is seated upon a plate member 46 which in turn is seated upon a block of urethane material 50 resting on a stationary base 52.

The splicing operation is seen performed particularly in FIGS. 4 and 5 wherein the sheets of material 10 and 12 are placed between the die halves 26 and 28 and the bottom sheet 12 rests upon the pin 40. The upper die 26 is lowered pressing the sheets downwardly and the cylindrical member 38 also downwardly to its position of FIG. 5 against the resilient and yieldable resistance to the urethane material 50. When the die halves are closed the sheets of material are sheared and deformed to provide elongated mating portions 60 and 62 having the general shape including parallel straight opposite side edges, of the male die element 28. The pin 40 has penetrated the center area of the lower elongated portion 6 and has spread the material laterally to form below sheet 12 arcuate shoulders 64 which prevent the elongated portion 62 from moving back into the opening 66 and 68 in the sheets of material 10 and 12 left by the shearing deforming and spreading steps. It is seen that the initial impact of the upper male die half 26 against the pin 40 is not damaging thereto since the pin is yieldable by the presence of the supporting urethane base. However, the urethane base is of such a quality that it becomes solid after it has been compressed by the movement of the pin 40 and cylindrical portion 38 downwardly to approximately in the position shown in FIG. 5 wherein only the pin 40 remains above the bottom surface of the cavity 36 in the lower female die half 27.

In FIG. 8 an alternative series of splices 70 are shown interconnecting the sheets of material 10 and 12 fed from the rolls 14 and 16. A pair of die halves 72 and 74 are shown having semielliptical male die portions 76 and 78 which matingly engage concave semielliptical die cavities 80 and 82 respectively. Since the die elements 76 and 78 are semielliptical in shape they each include perpendicular end surfaces 84 and 86 which are perpendicular to the faces of the die halves 72 and 74 and move in close registering relationship as seen in FIG. 10 and thereby cut the sheets of material 10 and 12 to form deformed portions 90 and 92 on one side and portions 94 and 96 on the opposite side of a plane extending along the line of separation of the pairs of deformed portions. It is seen that the deformed portion 90 on top has been deformed downwardly to a position nearly below the lower portion 96 on the opposite side which has been deformed upwardly an equal distance. The male die elements 76 and 78 are mirror images of each other as are the female cavities 80 and 82.

Thus it is seen that the mechanical splices of FIGS. 5, 7 and 10 are simple to make extremely effective in securing together a plurality of superimposed sheets of metal or other material.

Claims

I claim:

1. The method of bonding a pair of sheets of material together, comprising

placing first and second sheets in overlapping condition whereby a portion of one sheet extends over said other sheet to create upper and lower sheets,

placing an upwardly extending truncated conical pin below said upper and lower sheets and in contact with a portion of said lower sheet to be deformed,

imposing a force on said sheets to shear portions from said sheets and to deform said sheared portions from said upper and lower sheets to a position below the plane of the lower sheet,

permitting said pin to yield slightly during the initial stages of the imposition of said force, and holding said pin substantially rigid during the final stages of deformation of said first and second sheets whereby said pin penetrates the deformed portion of said lower sheet to expand said deformed portion of said lower sheet laterally beneath the lower sheet to prevent any realignment of said deformed portion to its original position.