US3035342A

US3035342A - Methods of producing a ribbed strip

Info

Publication number: US3035342A
Application number: US811209A
Authority: US
Inventors: George F Bashaw
Original assignee: Individual
Current assignee: Individual
Priority date: 1959-05-05
Filing date: 1959-05-05
Publication date: 1962-05-22
Anticipated expiration: 1979-05-22

Description

May 22, 1962 G. F. BASHAW Filed May 5, 1959 INVENTOR ATTORNEY JAM 769 May 22, 1962 G. F. BASHAW METHODS OF PRODUCING A RIBBED STRIP 2 Sheets-Sheet 2 Filed May 5, 1959 ATTORNEY 3,035,342 METHODS OF PRODUCING A RIBBEI) STRIP George F. Bashaw, 323 W. 2nd St, Tulsa, Okla. Filed May 5, 1959, Ser. No. 811,209 Claims. (Cl. 29-556) This invention relates to the metal-working art, and more particularly to metal-working involving die rolling and milling operations.

In the printing industry there is a demand for an extremely thin and flexible strip having a series of upstanding teeth extending along a longitudinal line on one face thereof, the opposite face being flat. Such a strip is employed for perforating or shearing the paper sheets being printed, and must be sufliciently flexible to permit of its being bent around the cylinder of an off-set press, and secured thereto by means of a suitable adhesive.

A perforating strip of this general nature is shown in Patent No. 2,842,202, Boyd, issued July 8, 1958.

A strip somewhat similar to FIG. 2 of the Boyd patent, with the series of teeth disposed along one edge, has heretofore been manufactured, sold and used, the upstanding teeth having been formed by a bending operation, resulting in a somewhat rounded edge, which is not desirable.

So far as I am aware, however, no one has been able to successfully produce the type of strip shown in FIG. 1 of the Boyd patent, namely, a strip with the series of teeth extending along a longitudinal line disposed between and spaced from the edges of the strip. For many purposes, this type of strip is more desirable. Neither has it heretofore been possible to commercially produce a strip similar to that shown in FIG. 2 of the Boyd patent, namely, a strip having a square edge adjacent the teeth.

The primary object of the present invention is therefore to devise an effective method of producing the type of strip shown in FIG. 1 of the Boyd patent, namely, a strip having a row of teeth, or serrated rib, extending along a longitudinal line intermediate the side edges thereof, but the invention may also be employed for producing a strip having such a rib extending along one of the side edges thereof, but with a square edge adjacent the rib or teeth, as shown in FIG. 2 of the Boyd patent.

It will be understood that the dimensions of such a strip in actual practice are exceedingly small. The entire width of the base is usually on the order of A; of an inch, while the height of the teeth or serrated rib may project perpendicularly from the base to the extent of to %000 Of an inch.

In fabricating the desired perforating strip, I start with a flat strip or ribbon of material which advantageously may be mild steel. While, for convenience in terminology, I refer to this in the specification and claims as flat bar stock, it might, on account of its thinness and flexibility, be described as a narrow tape. It is commonly referred to in the trade as wire. It comes from the mill in the form of large coils or reels, each containing many thousand feet.

Inorder that the invention may be readily understood, reference is had to the accompanying drawings, forming part of this specification, and in which:

FIG. 1 is a diagrammatic view showing my improved process in which the tape or stock passes continuously from the supply reel, successively over various instrumentalities employed to carry out the operations necessary to convert the stock into the desired product, and over suitable guide rolls to the take-up reel;

FIG. 2 is a fragmentary transverse section on a greatly enlarged scale, substantially on the line 2-2 of FIG. 1, showing the stock in position between the preliminary die or forming rolls;

FIG. 3 is a fragmentary side elevation of one of the die rolls;

FIG. 4 is a fragmentary side elevation comprising a portion of what is shown in FIG. 1, but on a much larger scale, and illustrating the stock as leaving the die rolls and passing under the milling cutters which I employ;

FIG. 5 is a transverse section substantially on the line 55 of FIG. 4, showing the shape of the finished strip as it emerges from the last milling operation, the milling cutter being indicated in broken lines.

FIG. 6 is a perspective view of the tape or bar stock as it appears after emerging from the die rolls as shown in FIGS. 1, 2 and 4;

FIG. 7 is a similar view showing the stock as it appears after having been operated on by the first set of milling cutters shown in FIGS. 1 and 4;

FIG. 8 is a similar view showing the completed perforating strip as it appears after leaving the second set of milling cutters illustrated at the right of FIG. 4, or as shown in FIG. 5;

FIG. 9 is a similar view showing a modified form of finished strip;

FIG. 10 is a transverse section similar to FIG. 5, but showing a slightly modified shape of rib or tooth;

FIG. 11 is a transverse section through a modified form of finished strip having the serrated rib at one edge thereof, this view illustrating my improved method of producing such a strip by shearing ofi the portion of the base lying at one side of the centrally form-ed rib, shown in FIGS. 5, 8 or 9; and

FIG. 12 is a view similar to the upper part of FIG. 2, but illustrating forming the teeth along or near one edge of the strip instead of the middle.

In producing the desired perforating strip from the tape or fiat stock referred to, the thickness of such stock must be at least equal to the thickness of the desired base plus the height to which the desired rib or teeth project from such base. Assuming that the finished strip is to have a base of an inch thick and a rib or teeth of an inch high, as given by way of example in the preamble, the thickness of the tape or flat stock would be /1000 Of an inch.

Referring to the drawings in detail, the tape or flat bar stock which 'I employ is designated at A and the shape of its cross section is best shown in FIG. 6. As above stated, it may be on the order of /s of an inch wide and on the order of of an inch thick. This flexible tape or stock is wound on a supply roll D.

From the supply roll the tape or stock is led successively between a pair of die rollers 1 and 2, between a milling cutter 12 and supporting roll 11 and between a second milling cutter 15 and a supporting roll 14. The tape or stock is also led around suitable guide rollers 10, 13, 16, 17 and 18, to a suitable takeup roll E. This roll is driven so that the tape or stock is drawn continuously under tension through all of the abovementioned instrumentalities.

The die rolls comprise an upper roll 11 and a lower roll 2, a fragment of the upper roll being shown on an enlarged scale in FIG. 3. Referring to this figure, and also to FIG. 2, it will be seen that the roll 1 has a central ridge 3 from which extend a series of projections or teeth 4. The roll 2 has a central circumferential groove 5 in which the ridge 3 closely fits, as shown in FIG. 2, and the tape or bar stock A is confined between the ridge and the bottom of this groove. As the stock is fed between the rolls 1]. and 2, the teeth or projections 4 are pressed into the stock, forming pockets or indentations in one surface thereof as clearly shown at 6 in FIG. 6. The material of the stock may advantageously be mild steel.

The stock, after leaving the die rolls 1 and 2, passes around the guide roller 10 and then between a milling cutter 12 and a supporting roll 11. This milling cutter is of the general shape indicated in broken lines at 15 in FIG. 5 and in full lines in FIG. 4, and is formed on each side of the center with straight horizontal cutting edges 15a, and at the inner side of these edges, with inclined cutting edges 15b. As the tape or bar stock moves under the milling cutter 12, some of the material at each side of the center line is removed from the upper surface thereof, thus substantially reducing the thickness of the stock, as shown at B at FIG. 7. The material between the inclined inner edges 15]) of the cutters is left intact, thus forming upstanding teeth 8 between the indentations or pockets 6, the length of these teeth being determined by the space 7 between the indentations as shown in FIG. 6.

After leaving the milling cutter 12 the stock B passes around a guide roller 13 and then between a second milling cutter 15 and a supporting roll 14. During this second milling operation further material is removed from the fiat upper surface of the stock, thus again substantially reducing its thickness until it assumes the form shown at C in FIG. 8. The final thickness of the base of the strip as shown at C may be on the order of of an inch.

During the final removal of material by the second milling operation, the upper surface of the stock is cut away on each side down to the level of the bottoms 6a of the original pockets or indentations, thus leaving between such bottoms upstanding teeth 9 as clearly shown in FIGS. 5 and 8. These figures represent the appearance of the finished strip in which the upper surface lies in the plane of the bottoms of the original indentations, and in which the teeth 9 project up to a height on the order of V of an inch. Thus, it will be understood that the upper edges of these teeth which, of course, he on a common horizontal line, really constitute a portion of the upper surface of the original stock as shown in FIG. 6, and that the combined thickness of the base C plus the height of the teeth 9 is equal to the entire thickness of the original stock as shown in FIG. 6.

While for the sake of clarity I have illustrated in FIGS. 3, 6, 7 and 8, by way of example, projections 4 of uniform size and shape, forming a series of similar indentations or pockets 6, and a series of simple regular teeth 9 of uniform length and spacing and having converging sides, it will be understood that projections 4, having any desired shape, may be employed to produce teeth such as 9 of any desired configuration or spacing. In my copending companion application, Serial Number 811,148, filed of even date herewith, I have shown various forms of teeth which I may employ to meet different requirements, and it is obvious that a die roller 1, having the type of projections 4 needed to produce any particular shape or spacing of teeth can be employed in carrying out my improved method. In fact, I contemplate that it would be the practice of a machine shop turning out these strips to keep on hand an assortment of die rollers such as 1, each having projections of a certain definite configuration and spacing, such die rollers being readily interchangeable, so that one may be substituted for another, as required, in accordance with the type of strip desired.

While it is theoretically possible to perform the milling operation in a single step, that is, to produce the finished strip as shown in FIG. 8 from the original bar stock shown in FIG. 6, that is, by using only one milling cutter, I find that it is preferable, because of the extreme thinness and frailty of the stock, to perform the milling operation in two steps as described, since this subjects the strip to less strain, and produces more accurate results.

The preceding description is based upon the assumption that it is desired to produce a strip having a row or series of teeth extending along the longitudinal center thereof, as shown in FIG. 1 of the Boyd patent. If, however, it is desired to produce a strip having the teeth adjacent one edge, as shown in FIG. 2 of the Boyd patent, I may accomplish this by shearing off the base of the strip at one side, as illustrated in FIG. 11. In this figure, after having produced a strip such as shown in FIGS. 5 or 8, I may cut off one side of the base, as indicated at C in broken lines, by means of a rotary or reciprocating shear 19.

As a further alternative I may form the projections 4 on the ridge 3 of the die roller 1, adjacent one edge thereof, as shown in FIG. 12. By this means the line of indentations 6 may be formed along one edge of the stock instead of in the middle thereof, and in this case the milling cutters would remove material from one side of this line only, to form the rib.

In either case, the finished strip would have a square edge adjacent the teeth.

The row of teeth 9 as shown in FIG. 8 may be regarded as a serrated rib, the teeth or serrations serving to form perforations in the paper and the space 6* between teeth or serrations serving to provide hinges or tear sections between the perforations in the paper.

Instead of a serrated rib such as shown in FIG. 8, it is sometimes desired to provide a strip having a continuous rib 20 thereon, as shown in FIG. 9. Such a strip would be used for creasing or scoring paper or light cardboard to provide fold lines, instead of lines of perforations. For this purpose the upper edge of the continuous rib 20 is preferably made a little broader or tblunter than the edges of the teeth 9.

In forming a strip with a continuous rib such as i1- lustrated in FIG. 9, I omit the die rollers 1 and 2 and feed the stock directly from the supply roll D to the milling cutters. The operation is exactly the same as described in connection with FIGS. 7 and 8, but, because of the fact that there are no pockets or indentations in the surface of the stock, the material left intact between the milling cutters forms a smooth continuous rib without any serrations therein. Thus, I may carry out my improved milling method either in combination with or without die rollers.

While I have shown in FIGS. 8 and 9 a continuous or serrated rib having both sides inclined or converging, the invention is not necessarily limited to the production of a rib of this cross-sectional shape. In FIG. 10 I have illustrated a rib, either continuous or serrated, in which one side 21 may extend at right angles to the base. This is accomplished by making the milling cutter with a cutting edge at one side, vertical, instead of inclined, as shown in FIG. 5.

Also, it is obvious that I may use grinding wheels for removing the material instead of milling cutters, and where, in the claims, I use the word milling I intend it to include grinding as well.

What I claim is:

1. The method of making a strip of material consisting of a thin, flat base having a longitudinally extending serrated rib having teeth projecting perpendicularly from said base at a point between the edges thereof, such method comprising starting with flat stock of a thickness at least equal to the combined thickness of said base and the height of the rib projecting therefrom, forming a series of spaced indentations in one face of said stock along a line extending longitudinally thereof, while maintaining the other face fiat, the depth of said indentations being equal to the desired height of the teeth making up said serrated rib, the length of said indentations corresponding to the distance apart of said teeth, and the spaces between said indentations corresponding to the length of said teeth, and progressively cutting away the material on said first mentioned face at each side of said series of indentations to an extent substantially equal to the depth of said indentations, leaving the original material of the stock at points between said indentations to form teeth projecting integrally from a base substantially thinner than the said stock.

2. The method of making a strip of material consisting of a thin, flat base having a longitudinally extending serrated rib having teeth projecting perpendicularly from said base at a point between the edges thereof, such method comprising starting with fiat stock of a thickness at least equal to the combined thickness of said base and the height of the rib projecting therefrom, forming a series of spaced indentations in one face of said stock along a line extending longitudinally thereof, the depth of said indentations being equal to the desired height of the teeth making up said serrated rib, the length of said indentations corresponding to the distance apart of said teeth, and the spaces between said indentations corre sponding to the length of said teeth, and progressively cutting away the material on said face at each side.of said series of indentations to a level surface lying in the plane of the bottoms of said indentations and constituting the upper surface of the desired base, leaving the original material of the stock at points between said indentations to form teeth projecting integrally from such surface of said base.

3. The method of making a strip of material consisting of a thin, flat base having a longitudinally extending serrated rib having teeth projecting perpendicularly from said base at a point adjacent one edge thereof, such method comprising starting with flat stock of a thickness at least equal to the combined thickness of said base and the height of the rib projecting therefrom, forming a series of spaced indentations in one face of said stock along a line extending longitudinally between the edges thereof, the depth of said indentations being equal to the desired height of the teeth making up said serrated rib, and the spaces between said indentations corresponding to the length of said teeth, progressively cutting away the material on said face at each side of said series of indentations to a level surface lying in the plane of the bottoms of said indentations and constituting the upper surfaces of the desired base, leaving the original material of the stock at points between said indentations to form teeth projecting integrally from such surface of said base, and then shearing off the part of said base lying at one side of said rib.

4. The method of transforming a flexible, metal tape having smooth flat faces into a toothed strip, which comprises drawing the tape progressively from a supply roll to a take-up roll, and, while traveling between such rolls, subjecting it first to a rolling operation to form a series of spaced indentations in one face of said tape along a. line extending longitudnially between the edges thereof, the spaces between said indentations corresponding to the length of the desired teeth, and then subjecting the tape to a milling operation to cut away the material from said face at each side of said series of indentations to such an extent as to leave the material of the tape at points between said indentations projecting integrally up from the cut away surface of the tape to form teeth of the desired height.

5. The method of transforming a flexible, metal tape having smooth flat faces into a toothed strip, which comprises drawing the tape progressively from a supply roll to a take-up roll, and, while traveling between such rolls, subjecting it first to a rolling operation to form a series of spaced indentations in one face of said tape along a line extending longitudinally between the edges thereof, the depth of said indentations being equal to the height of the desired teeth and the spaces between said indentations corresponding to the length of said teeth, and then subjecting the tape to a plurality of successive rnilling operations, each serving to cut away the material from said face at each side of said series of indentations so as to leave the material of the tape at points between said indentations projecting integrally up from the cut away surface of the tape to form teeth, the last of said milling operations serving to cut away the material to an extent substantially equal to the depth of said indentations.

References Cited in the file of this patent UNITED STATES PATENTS 763,952 Blondell July 5, 1904 1,271,787 Smith July 9, 1918 1,497,530 Mortensen July 10, 1924 2,335,626 Wintriss et al. Nov. 30, 1943 2,431,411 McKee Nov. 25, 1947 2,683,472 Specht July 13, 1954 2,754,581 Thomas July 17, 1956 FOREIGN PATENTS 94,188 Austria Sept. 10, 1923 452,596 Canada Nov, 16, 1948