US2866266A - Tool for nicking steel rule dies - Google Patents

Description

Dec. 30, 1958 v. 1-. HOEFLICH 2,366,266

TOOL FOR NICKING STEEL RULE DIES Filed March 16. 1954 2 SheetsSheet 1 a 64 64 "I M #4 [A I as 5 1 15.5 FIG 4 JNVENTOR.

' Karma 7. flaa z/r/a BY I a! Dec. 30, 1958 v. T. HOEFLICH 2,366,266

TOOL FOR NICKING STEEL RULE DIES Filed March 16, 1954 2 Sheets-Sheet 2 I N V EN TOR. 16:70? 7? #05:; /c'// United States Patent I TOOL FOR NICKING STEEL RULE DIES Victor T. Hoeflich, Forest Hills, N. Y.

Application March 16, 1954, Serial No. 416,593

2 Claims. (Cl. 30-277) This invention relates to'a tool for nicking steel rule dies.

Steel rule dies have been widely used for many years to cut paper or cardboard. A problem arises in handling the punched sheet, for it tends to fall apart as it is being removed from the press. To avoid this the various pieces of the punched sheet are preferably held together by very Weak cross connections at spaced points. These are made by nicking the steel cutting rule at corresponding points. The usual practice is to employ a screwdriver blade or like which is hit lightly with a hammer against the cut ting edge of the steel rule. This procedure has been used for many years.

If the nick is too small the connecting bridge of fibre will be too weak, and the sheet will fall apart as it is being handled. If the nick is too large the connecting bridge will be too strong, and there is excessive resistance When pushing the punched pieces apart. Small tears may result at the bridges, and these may blemish the product, particularly when the paper is finished with a metallized or other ornamental surface. Particular dilficulty may arise when using a material of known type in which strands of rayon or other thread are cemented in parallel relation on paper board. If the nicks are too large the punched pieces when pushed apart may lift up a complete uncut thread, thus marring the product visibly.

The primary object of the present inventionis to overcome the foregoing difiiculty, which I do by constructing a tool which gives a standardized predetermined depth of nick. The depth is adjustable, and when once the tool has been adjusted for best results with a particular steel rule working on a particular paper, the adjustment is readily maintained, and uniform nicks may be produced at suitable points on the die.

In accordance with further features and objects of the invention the tool is so designed as to orient the nicking edge in perpendicular relation to the cutting edge, and a scale may be provided to indicate the force of the hammer blow which produces the nick. Thus a skilled workman may make note of his experience with different kinds of paper stock, and reproduce the optimum nick whenever again working with the same paper stock.

To accomplish the foregoing general objects, and other more specific objects which will hereinafter appear, my invention resides in the tool for nicking steel rule dies, and the elements thereof and their relation one to another, as are hereinafter more particularly described in the following specification. The specification is accompanied by drawings, in which:

Fig. l is a perspective view of a platen press of clam shell type, which is one of a number of forms of press which may be used to carry a steel rule die;

Fig. 2 is an elevation of a preferred form of tool embodying features of my invention;

Fig. 3 is a longitudinal section taken approximately in the plane of the line 3--3 of Fig. 2;

Fig. 4 is an end View of a bifurcated chisel forming a part of the invention, drawn to enlarged scale;

Fig. 5 is a partially sectioned view taken approximately in the plane of the line 55 of Fig. 4;

Fig. 6 is a partially sectioned view taken approximately in the plane of the line 6-6 of Fig. 4;

Fig. 7 shows a fragmentary part of a blank punched in a steel rule die;

Fig. 8 is a partially sectioned fragmentary view drawn to enlarged scale and showing the edge of a steel cutting rule before and after nicking;

Fig. 9 shows the normal cutting action of the steel rule;

Fig. 10 shows the modified action of the steel rule at a nicked point;

Fig. 11 is a simplified plan view of a'steel rule die, drawn to small scale;

Fig. 12 is a similar view of a modified steel rule die;

Fig. 13 is a fragmentary section taken approximately in the plane of the line 13-13 of Fig. 11;

Fig. 14 is a fragmentary view showing the steel rule provided with a cork; and

Fig. 15 is a similar view with the cork compressed.

Referring to the drawing, and more particularly to Fig. 1, I there show a conventional platen press 12 of the clam shell type having a stationary platen 14 on which a steel rule die 16 is fixedly mounted. There is a bed 18 on which a sheet of heavy paper, paper board, or cardboard or the like is laid. When the press is tripped the bed 18 is oscillated and pressed hard against the steel rule die 16, following which the bed comes back to its outer position and the sheet is removed by the operator and replaced by a new sheet.

It will be understood that steel rule dies are used in other presses, as for example, reciprocating presses, single cylinder presses, and two-cylinder presses.

Referring now to Fig. 7, I there show for purposes of illustration a sheet 20 from which a series of nested facial masks are to be punched. These masks are indicated at 22, 24, 26, etc., and each is provided with eye openings 28 and ear openings 30, the upper part of the nose of the wearer being received at 32. It will be evident that if the cutting operation were performed with complete severance it would be difficult to handle the sheet after it has been punched, for it would fall apart during handling.

Referring now to Fig. 13 of the drawing, a steel rule die is made up of relatively thin steel cutting rules 34, 36 which are secured in desired relative position by appropriate inserts or blocks 38, 40 and 42 commonly called furniture. The rules are backed'by a hard surface such as that of the steel platen 14.

Referring now to Fig. 11, the die 50 may be received within a metal chase or frame 52, the parts of the die being compressed by filler strips 54 and a suitable wedge 56. The wedges may be quoins in which mating half wedges are moved relative to one another by means of a special key or crank inserted in a suitable socket 58. In transverse direction the die is held by filler strips 60 and wedges 62. It will be understood that steel rule dies are inexpensive and convenient because the steel rule may be bent to follow the configuration of the furniture, and the furniture is usually made by means of a thin jigsaw or bandsaw cutting through a suitable plywood board, and the cut of the saw may correspond to the thickness of the steel rule.

In some cases the pressure of the furniture against the rules is sufficient, without necessitating wedges, and such an arrangement is shown in Fig. 12, in which the die portion 64 is made from the same piece of wood as the surrounding frame 66, and the only pressure exerted on the steel rules is that which arises from hammering the furniture back in place around the steel rules.

As is known, the steel rule die cuts against a fiat bed rather than against another die, and the depth of cut must therefore be precisely regulated. The make-ready includes insertion of shims made of paper tape or other material behind one rule or another until all rules cut evenly and uniformly through the sheet being cut. The bed may be hardwood, or a thin sheet of hard pressboard may be glued on topof a steel plate, and this may be scraped or thinned as an additional step in makeready.

After the die has been assembled and adjusted, the cutting rules are preferably nicked at intervals to spoil the cutting action at the nicked points. Thus referring to Fig. 7 it will. be seen that the severance lines are interrupted at intervals thereby leaving bridges of material as shown at 70, 72, 74, 76, 78, etc. It will be understood that the bridges shown in Fig. 7 have been exaggerated, and that in practice the material is almost cut through but a 'small bit of fibre is. left intact. The connection is so weak that the parts are readily pushed apart with, aminimum ofresistance, and with no damage'to'the surfaceof thev finished product. However,

the connection cannot be made so weak that parts will fall or turnout from the sheet unintentionally, for this greatly slows and complicates the handling of the sheets. To producethe bridges the steel rules have been nicked by simply hitting the edge with a screwdriver and hammer, but this practice, although universally followed for many years, is not satisfactory because the nicks are not uniform, and thus the bridges are not uniform in strength.

I have accordingly originated a nicking tool which may be described with reference to Figs. 3 through 6 of the drawing. This comprises a barrel assembly generally designated 80, the said assembly being similar in character to a spring loaded hammer. The tool preferably includes means, in this case a rotatable cap 82, to

adjust the force of the blow produced by the barrel assembly 80. The tool further includes a hardened steel tool head 84, the cutting. part of which is a blunt chisel edge 86. The tool preferably is bifurcated to provide spaced side walls 88 which are preferably substantially parallel, and the spacing therebetween ispreferably only slightly greater than the thickness of the steel rule. The cutting edge 86 is disposed perpendicularly to the side walls, and thus is held at right angles to the steel rule when the bifurcated end of the tool is placed astride the cutting edge of the steel rule. Because of the spring loading and escapement action of the barrel assembly, and because of the shape of the cutting head, it will be understood that the nicks produced by the tool are uniform. This assumes that there is no significant difference in the hardness of the cutting rules, and in practical cases that is true because the cutting rules used in a single die come from common stock. In most shops the diemaker tends to favor and to order a particular hardness, so that there may be little or no difference even over a period of years.

The internal construction of the barrel assembly may correspond to any of a number of known constructions. In that here shown the tool head is mounted on a plunger 90, normally urged outward by means of a light compression spring 92. The inner end of the plunger is stepped to provide a ledge or shoulder at 94. The shoulder bears against a sear 96, which initially acts on a ram 98, which in turn presses against a main compression spring 100, the upper end of which bears against the top of cap 82. The latter is threaded on cylindrical housing 102. Thecylindrical housing has an internal step or ledge at 105, and this cooperates with a camniing surface formed at the end of sear 96. When the cylindrical housing 102 and cap 82 are pushed downward relative to plunger 90 the light spring 92 is compressed until collar 110 of plunger 90 bears against the lower end of bushing. 106. Also the heavy spring 100 is compressed, andsear 96 is carried up to the step 105. On continued motion the sear is moved radially by the step 105 until the hole in the sear is aligned with the inner end of plunger 90, whereupon the loaded main spring 100 drives the ram 98 forcibly downward about the inner end of plunger 90 until the lower end 104 of the ram 98 hits the bearing surface or bushing 106 at the upper end of the tapered part 108 of the barrel assembly. At this time the collar 110 of plunger 90 is bearing against the lower end of bushing 106, and consequently the force of the spring blow is transferred directly to the plunger 90 and the tool head. When the tool is lifted the parts are restored to, initial position by the springs 92 and 100. There is also a leaf spring 112 which returns the sear 96 radially outward to its initial position, at which time it comes above the shoulder 94 of plunger 90' and thus keeps the lower end 104 of ram 98 spaced from the bushing 106 preparatory to the next hammer action.

The mounting of the tool head 84 on the plunger 90 is preferably made detachable, as by providing the tool head with a threaded shank 114 received in a mating threaded hole in the end of plunger 90. The tool head is preferably made of a good quality hardened steel, the hardness of which safely exceeds that of the cutting rules used in the die. There is accordingly no need for sharpening the tool head, but should one become dull it is readily and inexpensively replaced by another tool head. The tool head may be made but cutting the bifurcation with a thin circular cutting tool working from opposite sides, so as to leave the desired cutting edge between the sides of the two cuts.

In practice the barrel assembly is preferably supplied as part of a kit, with a number of tool heads having different spacing at the bifurcated end. This is because steel rules come in varying thicknesses, there being nine thicknesses in common use ranging from 0.014" to 0.166. This is a greater range of thickness than would ordinarily be used in a single shop, and the number of tool heads supplied with a single barrel could be less in number. Indeed the range of thickness above indicated is greater than the feasible range of adjustment of a single barrel, and a complete tool kit could consist of two or even three barrel assemblies, each with appropriate tool heads dimensioned to work with cutting rules which may be nicked by the particular size of barrel assembly.

The particular barrel assembly here shown is designed like that made commercially available by General Hardware Mfg. Co. of New York City and identified as No. 79. The main compression spring 100 normally supplied may be used for thin steel rules, but is replaced by a heavier spring when dealing with steei rules of greater thickness. However, other mechanisms may be used, such as those employed in spring loaded barrels made by Brown & Sharpe, and by Starrett, and by Eclipse, but in each case it is preferred that the force of the hammer blow be adjustable.

Indeed, in the present tool the adjustment is preferably aided by the provision of a scale, and referring to Fig. 2 it will be seen that there is a circular scale cooperating with a pointer or indicator line 122 on the sleeve 102. This in turn preferably has axial scale markings 124, thus accommodating an adjustment of multiple turns.

Optimum result is initially determined by trial and error. The die is nicked to a first depth and some trial cuts are made in the press. If the punched sheet comes F apart too easily the hammer is set for a slightly greater blow and the die is again nicked. When the proper depth has been determined the adjustment of the tool is kept for the whole die, and may be noted for future use when dealing with the same thickness of cutting rule and the same paper. Thus, little or no trial and error will be needed when a repeat situation is encountered. The scale is, of course, useful even during a single series of trials and adjustments, as a measure of how much adjustment is being made each time.

I at 144.

Referring now to Fig. 9, the normal action of steel rule 140 is to cut through the cardboard 146 resting on a suitable support plate or bed 148. Fig. is similar to Fig. 9, but shows the action at one of the nicks 144. It is evident that because of the nick a bit of fibre is left unsevered as shown at 150. This, of course, is one of the points indicated at 70, 72, etc. in Fig. 7.

The stripping of the cut sheet from the die is ordinarily accomplished by gluing a series of small cork or rubber pads about the die, and the action of these is illustrated in Figs. 14 and 15. Fig. 14 shows one of the cork or rubber blocks 130 in expanded condition before being squeezed against the paper web 132 resting on bed 134, while Fig. 15 shows the compression of the block 130 when the bed 134 is forced against the cutting rule. It is evident that when the bed and die are separated the resilient blocks 130 will strip the punched sheet 132 from the die, thus permitting the sheet to remain on the bed 134.

It is believed that the construction of my improved tool for nicking steel rule dies, as well as the advantages thereof, will be apparent from the foregoing detailed description. It will also be apparent that while I have shown and described my invention in a preferred form, changes may be made without departing from the scope of the invention, as sought to be defined in the following claims.

I claim:

1. A tool for nicking the cutting rules of steel rule dies, said tool comprising a barrel assembly similar in character to that of a spring loaded hammer, and a hardened steel tool removably mounted on the working end of said barrel assembly, said working end being freely rotatable relative to the rest of the barrel assembly, said tool comprising a straight bifurcated end portion with closely spaced substantially parallel inside walls having a spacing somewhat greater than the thickness of the steel rule, a centrally disposed transverse cutting edge extending across said space so that said cutting edge is held transversely of the cutting rule when the bifurcated tool end is placed astride the rule, and the portions of the tool between the sides of the tool and the cutting edge being removed to provide angular surfaces so as to provide a rule nicking cutting edge.

2. A tool for nicking the cutting rules of steel rule dies, said tool comprising a barrel assembly similar in character to that of a spring loaded hammer, and a hardened steel tool removably mounted on the working end of said barrel assembly, said working end being freely rotatable relative to the rest of the barrel assembly, said tool comprising a straight bifurcated end portion with closely spaced substantially parallel inside walls having a spacing somewhat greater than the thickness of the steel rule, a centrally disposed transverse cutting edge extending across said space so that said cutting edge is held transversely of the cutting rule when the bifurcated tool end is placed astride the rule, the portions of the tool between the' sides of the tool and the cutting edge being removed to provide angular surfaces so as to provide a rule nicking cutting edge, said barrel assembly comprising a cylindrical body with telescopic parts housing a main spring and a scar which is released when one telescopic part is pushed down on the other, one of said parts having a rotatable threaded cap bearing against one end of the spring to adjust the force of the spring at the point of release of the sear.

References Cited in the file of this patent UNITED STATES PATENTS 280,995 Armstrong July 10, 1883 393,880 Binkerd Dec. 4, 1888 843,655 Adell et al Feb. 12, 1907 889,409 Spalding June 2, 1908 976,758 Warwick Nov. 22, 1910 1,458,961 Williams June 19, 1923 1,572,046 Seiler Feb. 9, 1926 2,029,495 Lowe Feb. 4, 1936 2,455,270 Ravella Nov. 30, 1948 2,490,684 Gosselin Dec. 6, 1949 2,757,452 Barnes Aug. 7, 1956 FOREIGN PATENTS 121,962 Sweden June 15, 1948

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