BRIEF DESCRIPTION OF THE DRAWINGS
The objects and advantages of the present invention will become more apparent, when viewed in conjunction with the following drawings in which:
FIG. 1 is a perspective view of an elongated punch of the present invention, having a central bore with an ejection plug extending slightly therefrom;
FIG. 1A is a side elevational view, partly in section, showing a punch arranged adjacent a die with a piece of sheet metal arranged therebetween;
FIG. 2 is a perspective view of an ejection plug constructed according to the principles of the present invention;
FIG. 3 is a perspective view of a punch, with a plurality of elongated bores extending therethrough, with a further bore for receipt of a retaining screw therewithin;
FIG. 4 is a side elevational view of a punch in transverse section, showing an ejection plug extending therewithin;
FIG. 5 is a view taken along the lines 5-5 of FIG. 4;
FIG. 6 is a view similar to FIG. 4, showing an elongated punch with a bore extending therethrough and a further embodiment of an ejection plug therewithin;
FIG. 7 is a view taken along the lines 7-7 of FIG. 6;
FIG. 8 is a side elevational view of an elongated punch in transverse section, showing an elongated ejection plug extending therewithin;
FIG. 9 is a side elevational view of the ejection plug shown in FIG. 8; and
FIG. 10 is a view taken along the lines 10-10 of FIG. 9.
DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
Referring now to the drawings in detail, and particularly to FIG. 1, there is shown the present invention which comprises a die punch 10 for the metal stamping industry. The die punch 10 for our description purposes, is circular in cross section, (although it may be of any cross sectional shape), is driven through a piece of sheet metal 12, and through a die 14 or opening through which a plug 16 of that shape metal 12 is pressed, as represented in FIG. 1A. A punch 10 of the present invention is for example, circular in cross section, as may be seen in FIGS. 13, 5 and 7, having a cylindrical bore 20 extending longitudinally therethrough, as represented in FIGS. 4 and 6. The punch 10 has a distalmost end 22 having a sharp peripheral edge 24 which pierces the sheet metal 12 creating the slug 16. The punch 10 then intendedly pushes that sheet metal slug 16 through the shaped die 14 there adjacent. That punch 10 has a proximal end 26 typically with an annular lip or shoulder 28 thereon for securement of that punch 10 in a press or driving means (not shown for clarity of figures) for moving that punch 10 through the die 14.
The punch 10 has that longitudinal bore 20 extending therethrough, from the distal end 22 to the proximal end 26 in a first preferred embodiment thereof. That internal bore 20 may be slightly tapered, with the widest end of that bore 20 disposed at the distalmost end 22 of the punch 10, for securement purposed described hereinbelow.
In a first aspect of the present invention, an elongated ejection plug 30 is disposed within the elongated bore 20 of the punch 10, as represented in FIG. 1. The elongated ejection plug 30, in a preferred embodiment thereof may comprise a soft elastomeric material having a distalmost end 32 and a proximal end 34, as represented in FIG. 2. An end view of the ejector plug 30 may look like a clover shaped device. The ejector plug 30 may preferably be comprised of three parallel, elongated lobes or flanges 36 which mate snuggly within the bore 20 of the punch 10. The distal end 32 of the ejector plug 30 has three extensions 40 thereon which are preferably hemispherically shaped, as represented in FIGS. 1, 1A and 2. The hemispherically shaped distalmost end extensions 40 of the ejection plug extends distally beyond the distal end 22 of the punch 10, as may be seen in FIGS. 1, 1A, 4, 6 and 8.
In yet a further embodiment of the present invention, a longitudinal main bore 48 extending through the elongated generally cylindrically shaped punch 10 may itself may be of “clover” shape, as represented in FIG. 3, while having a plurality of elongated individually extruded ejector plugs 50 extending therethrough. Each individual ejector plug 50 in this embodiment has a distalmost end 52 of slight round or hemispherical configuration. The distalmost ends 52 each extending slightly distally (out of and) beyond the distal end 22 of the punch 10. A central lumen 54 of the longitudinal bore 48 extending through the punch 10 is disposed within the geometric longitudinally centralized location of the outwardly disposed ejection plugs 50 disposed therein. An elongated screw 56 may be disposed within that central lumen 54, so as to lock the three ejection plugs 50 snuggly within their respective parallel bores 58 of the main bore 48. The threaded screw 56 is preferably a polymeric material or other resilient non-metallic material.
A further embodiment of the ejection plug 30, is shown in FIGS. 6 and 7. The plug 30 is shown best in FIG. 7, may be comprised of a generally cylindrically extruded elongated polymeric member 60 having a proximal end 62 and a distal end 64. The distal end 64 having at least three hemispherical or semi-spherical protrusions 66 thereon, surrounding a central bore 68 extending through that ejection plug 60. That central bore 66 may be utilized for a polymeric screw 69 extending therethrough to expand that ejection plug 66 within the walls of the bore 20 through the elongated punch 10.
A yet further embodiment of the present invention comprises an elongated punch 70, having a proximal end 26 and a distal end 22, as represented in FIGS. 8 and 9. The distal end 74 has a bore 76 extending part way therein, comprising a “blind hole” in that punch 10. An elongated ejection plug 78, generally cylindrical shape, having a proximal end 80 and a distal end 82 is insertable within that elongated blind hole 76 through the distal end 22 of the punch 10. The elongated ejection plug 78 in this embodiment may have a central bore 86 therethrough for receipt of a screw, not shown for clarity, therewithin. That screw may be utilized to expand the walls of the ejection plug 78, and/or to attach the ejection plug 78 to a threaded bore 88, centrally within the bottom of the blind hole 76, as represented in FIG. 8. The distalmost end 82 of this particular ejection plug 78 preferably has at least three hemispherical extensions or protruberances 90 thereon, extending distally beyond the distalmost end 22 of the punch 10 in which the ejection plug 78 is inserted. The hole or bore 76 in this embodiment is preferably tapered to a wider dimension towards its distal end.
In operation of the ejection plug arrangement for a punch present system as represented in FIG. 1a, the distalmost end of the ejection plug insert, extends beyond the distalmost end 22 of the punch 10 so that when the punch presses through a piece of sheet metal 12 in longitudinal engagement with a die 14, those protruberances 40 et al. extending beyond the distal end 22 of the punch 10 do compress slightly but give enough pressure to the slug 16 being punched through the die, so as to completely eject it therethrough and out the other side of that die. That slug does not get held up or put into misalignment within the die 14 itself, because of the spaced apart triangular nature of the hemispherical ended ejection plugs 40 etc. pushing thereagainst, from the distal end 22 of the punch 10.
Patent Application
20070283795
