US3120922A - Mechanical apparatus - Google Patents

Description

Feb. 11, 1964 J. E. WALDRUM 3,120,922

MECHANICAL APPARATUS Filed Nov. 20. 1961 I 3 Sheets-Sheet 1 o [*1 m INVENTOR. J m 2 9 JOHN E.WALDRUM BY W5 Wm ATTORNEY J. E. WALDRUM MECHANICAL APPARATUS Feb. 11, 1964 3 Sheets-Sheet 2 Filed Nov. 20, 1961 Fig. 3

INVENTOR. JOHNEWALDRUM ATTORNEY Feb. 11, 1964 J. E. WALDRUM 3,

' MECHANICAL APPARATUS Filed Nov. 20, 1961 s Sheets-Sheet s llllllfillll llll 72 96 70 7O 7o 72 Fig.4 9 5 Fig.6

INVENTOR. JOHN EWALDRUM 5 WW6, W

ATTOR NEY United States Patent Ofiice Tarzafazt Patented res. ll, was

3,1l2li,922 MEQHANMJAL APPARATUS John E. Waldrum, Ambler, Pan, assignor to Waldrum Engineering Corporation, North Wales, Pa, a corporation of Pennsylvania "Filed Nov. 2d, 1961, Ser. No. 157,295 '7 (@l. Tad- This invention relates to punching apparatus and the like and in particular to high speed, electro-mechanical rotary punching mechanisms.

In the data-processing art it has become customary to impress information upon an appropriate medium such as cards, paper or magnetic tape, etc. This information may be in the form of visible markings, magnetic signals, or perforations in the medium as the case may be. While certain areas of data-processing technology have advanced to the point where literall millions of operations may be performed each second, other areas of that technology are considerably slower. One area which is slower is the punching operation for cards or tape. One reason why this area is relztively slow is the fact that mechanical and electromechanical apparatus is required and therefore the inertia of the moving parts plays a limiting role, especially where high speed punches are used. Punching speeds on the order of 600 cards per minute are about the fastest presently known, but it is highly desirable to increase this speed by a factor of two to perhaps five.

it is therefore a principal object of the present invention to provide a novel mechanism for impressing information on selected media at a very high speed.

Still another object of the present invention is to provide a novel high speed punching device characterized by lowinertia moving parts which be selectively actuated at very high speed.

Still another object of the present invention is to provide a novel rotary, high speed punching mechanism for producing perforations in selected media at a rate which is at least double the fastest rate presently attainable with known mechanisms.

The present invention also may be useful in other types of information recording and extraction applications as will be mentioned herein.

"hese and other objects of the invention are accomplished in one form of the invention by providing a plurality or" punching elements which are normally impelled outwardly through apertures in a highopeed revolving drum by centrifugal force. Associated with the punch ing elements are pivotally-mounted pawl-like members which are normally disengaged from the punch element. There is also provided electromagnetic means completely separate from the pawl and punching elements which, in response to an electrical signal applied thereto, causes the pawl member to shift position to engage the inner end or" the punching element. (Ionsequently, the latter cannot be moved axially inward (toward the center of the drum) and thus when it rotates it can perforate the card. if no signal is applied to the electromagnetic means, the pawl member does not touch the punching element and hence the latter will be pushed axially inward by the card when the punch element touches it. Another drum is also provided which has apertures therein arranged to be engaged by the punch elements when they are in their outward position. Other forms and features of the invention are explained below.

FEGURE 1 is a side elevation View of rotary punching apparatus constructed according to one form of my invention;

FEG'URE 2 is a side sectional view taken along the longitudinal axis of the upper rotary drum shown in FIG. 1'

FIGURE 3 is a transverse sectional view of part of the upper and lower drums shown in FIG. 1 taken in the direction of the arrows associated with the section line 33;

FIGURE 4 is an enlarged detail of part of the sectional view of FIG. 3 wherein two successive punch operations are shown;

FIGURE 5 is an enlarged detail of part or" the apparatus shown in FIG. 3 showing a no-punch operation followed by a punch operation;

FIGURE 6 is an enlarge sectional detail of part of the transverse sectional View shown in FIG. 3 showing how the information medium is fed to the punching apparatus;

FEGURE 7 is an elevation view, partly in section, of another embodiment of my invention; and

FlGURE 8 is an elevation view, partly in section, of another a ternative embodiment of my invention.

Overall Drum Structure Referring to FIGS. 1 and 2, the overall punching apparatus is shown which consists of two drums 4t and mounted between two upright plate-like mounting members l2 and which are fixed to (or integral with) a horizontal base plate The upper drum 4% is supported at its left end by a toothed collar portion 56 having a ball-bearing assembly which encircles projection 13 from the plate 12. On its right side, the drum 4% has a tootl ed disc-like end portion 53 from which extends a projection and a smaller iameter extension 62 thereof which is upported in the aperture 22 in supporting plate i l by means of a ball-bearing assembly indicated generally at numeral 6d.

There are two threaded apertures 1e and 2b in the plate 32 and two unthreaded apertures 22 and 2.4 in the supporting plate 1d. Along the longitudinal axis of the drum there is a fixed hollow shaft 26 which passes through aperture 27 in the toothed collar 55. Shaft 26 has a threaded left end portion 26a, of smaller overall diameter than the central portion, which is screwed in aperture 18. Around this end portion a nut 28 (or similar fastening means) is screwed against a washer St? or similar device. The shaft 26 is hollow to permit the entry of a number of electrical leads 32 therein from a programmed signal source 34. As shown in FIGS. 2 and 3, the shaft contains a longitudinal slot '79 through which pairs of the leads 32 come out for reasons to be described below. Fixedly mounted about the shaft as are two supporting members Stl and 82, each consisting of an eyeletshaped head section which surrounds the shaft 26 and is fixed thereto by set screws 53 or other appropriate means, and a lower portion fixed to or integral with the head portion. A mounting bar 84- is screwed at each end between the lower portions of till and 82 respectively. A plurality of permeable cores 83 are fixed by force-ht insertion, for example, into apertures in the lower edge of the bar 84. A plurality of windings 9d are associated with corresponding ones of the cores These cores 38 are made of a ferromagnetic material, for example, and enable each of the core-coil combinations 8%, 9% to function as an electromagnet. Each of the coils 3 is coupled to a different pair of the leads 32 from the source 34. Between adjacent ones of the cores 88 are located magnetic shields 92, made of a highly permeable material such as Mu-metal whic serve to localize the field produced by each of the electromagnets so as to prevent stray or fringe magnetic fields from causing improper actuation of neighboring ones of punch elements 42 which will be described below. Alternatively, each of the core-coil elements (3%, 99) may be surrounded by a cylindrical or other shaped shield of highly permeable material.

Drum 40 Details As shown in FIGS. 1 and 2 the drum 40 consists of a number of arcuate segments 41 which are clamped together by bolts or pins 63 between the toothed member 55 and annulus 57 on the left, and annulus 5 9, member 61 and the toothed member 58 on the right. There are a number of punching elements 42 (FIGS. 2, 3, 4 and 5) which pass through apertures 4-3 Within each one of the segments 41. Each of the elements 42 may have a generally circular cross-section (or other desired cross-section) and is prevented from falling out of its corresponding aperture 43 by a retaining ring '45 (or similar element) which is fixed to the end portion 42a. There is associated with each of the punching elements 4?, near each one of the cores 88 a pawl-like member 47 which is pivotally mounted about a pin 49 which is mounted transversely to the recessed surface 41a. The segments 41 also have a recessed surface 41b to facilitate nesting.

Lower Drum 50 Structure Below the drum 4% and geared thereto for synchronous movement in an opposite rotary direction is the die drum 50 which contains a number of apertures 70. These apertures may be formed in a number of contiguous curved segments 72 which may have a cross-section generally similar to that of the segments 4-1 of the drum 40. Segments 72 are bolted together by a number of members 74 which pass through apertures in each of the segments 72 as shown in more detail in FIG. 3. The ends of the members 74- are threaded and nuts 76 are screwed on them to maintain the segments 72 tightly pressed together between annular members (not shown) and the toothed end members 79 and 8 1 similar to the mounting of the segments 41 of the drum 4d. The right hand end of drum 5%) is mounted in practically the same way as the right hand end of drum 40 except that the projecting shaft 89 (FIG. 1) is coupled to the shaft of a driving means such as a motor 10. Of course, belts may alternatively be used as well as other forms of power transmission and generation.

To collect the punched-out card bits there is disposed within the drum 50 a stationary vacuum-powered collector indicated generally at the numeral 97 (FIGS. 1 and 3). This collector consists of an elongated generally U-sectioned portion connected to a hollow shaft portion 98 which passes through an aperture (not shown) in the toothed member 79 and the aperture 20in the vertical plate 12. The extreme left end of the shaft 98 is threaded and a nut 101 is screwed thereon to keep it in a fixed position. The shaft 98 is coupled to an air-tight tubing 99 which is connected to an appropriate vacuum generator 100.

The ends 97a of the U-shaped portion of collector 96 are flared (FIG. 3) and located near the active punching region, i.e., the region near the tangent common to both drums. In FIG. 3 the collector 96 is shown positioned symmetrically with respect to the axis of the die aperture which is being punched, but it can be located more to the left, for example, to account for the fast rotary movement of the drum 50.

Operation Punch Elements The operation of the punch elements will now be considered with particular reference to FIGS. 4 and 5. In FIG. 4, the left pawl-like member 4 7 is shown with its tip portion 47a touching retainer ring i at the end of one of the punch elements 42 which has just punctured the card or other medium 96 and is passing through a die aperture 70. The right member 47' (also FIG. 4) is shown in the same position as the member 47 since another punching signal has been applied to the coil 90 which therefore attracts the end 47b upward. Thus, 47 has been moved from its rest position (shown in phantom) wherein its portion 47b rests on a pin 51' also fixed transverse to surface 41a, to its actuated position wherein its end 47a prevents inward axial move ment of the next element 42 when it touches the card 96.

Ordinarily, when the drums 4t}? and Stl are rotating at high speed, each one of the elements 42 will, by centrifugal force, be urged outwardly through its corresponding aperture 43 so that it is introduced into a particular one of the die apertures 76. At the same time the member 47 will be at its rest position because the part of member 47 to the right of its pivot pin 49 is larger and therefore heavier than the part to the left of pin 49. Consequently, when the drums are rotating at high speed the right portion (which includes 4712) will be urged outward (downward in FIGS. 4 and 5) by centrifugal force. In such a case, if there is no signal applied to the associ ated core 83 when the punching element 42 meets the medium 96, it will be pressed inward and will not perforate the medium 96. This is shown in FIG. 5 wherein the left member '47 was in a rest position (phantom depiction) when the coil 9% began to be energized. The portion 47b of the left member 47 may be slightly ele vated by the fringe magnetic lines of the field building up to actuate 47, but it will be prevented from further countor-clockwise pivotal movement by the retaining ring 45 of the element 42 which has been pushed inward by the card 96. As the field builds up, the right member 47 will have its portion 47b drawn up toward the core 88 and its tip portion 47a will engage the retaining ring 45' as shown preventing inward axial movement of the element 42 thereby enabling it to perforate the card 96. As the drum continues to rotate, the element '47 will move out of the field of the core which will be energized by new punch signals as may be supplied by the programmed signal source 34. The element 47 and the element 42 being free from the magnetic field, will then revert to their normal rest positions under the influence of centrifugal force.

Feeding of Medium While it is not essential for purposes of this invention that the medium to be perforated must be applied to the high-speed perforating apparatus in any particular manner, it will be appreciated that if the card is fed to it with its long edge first, all of the perforations may be made more quickly. If the card has twelve columns of possible information locations arranged parallel to the long edge of the card and each column is to have say, eighty information locations behind one another, the punch drum 40 will have, assuming that two cards are to be processed per revolution of the drum, eighty pairs of opposed segments 41 disposed adjacent one another, each segment having twelve punch subassemblies as shown in FIG. 3. No particular method is required to feed the cards to the perforator, but one possible way is shown in FIG. 6 wherein the medium 96 has its long edge applied between the two drums just when the gap 48 between two of the segments 41 of drum 40 is located opposite the corresponding gap S3 between two segments 72 in the lower drum 50. Of course, there is no reason why the perforating apparatus cannot be made so that the card can be fed to the apparatus in the usual fashion, i.e., with its short edge first.

Other Embodiments While the invention has previously been explained in terms of one stationary bank of electromagnets arranged in a row so that each electromagnet actuates the punch assemblies in each pair of opposing ones of the segments 41, it should be appreciated that it is also capable of being adapted to other embodiments. If just one row of electromagnets is used, as illustrated in FIGS. 1, 2 and 3, less time is provided for enabling the pawl-like member to move from its rest position to its punch position and, by the same token, less time is provided for enabling the pawl-like member to revert to its rest position once it has performed its function in a punch operation. With a plurality of electromagnets, one for each of the punch subassemblies, this disadvantage may be overcome because the actuating signals may be applied to cores associated with the pawl members well in advance of the time that those pawl members and their corresponding punch elements enter the punching region, -i.e., the region where the two drums come together. Thus the operating speed of the apparatus and therefore the perforating capacity may be increased. For example, each of the punch subassemblies consisting of one of the pawl elements 47 and one of the punch elements 42 could have associated with it a separate electromagnet which is mounted on the segment 4-1.

In FIG. 7 there is shown a pawl-like element 47" having a configuration somewhat different from those previously discussed and also a punch element 42" which may be identical to those previously described. In addition, there is an electromagnet consisting of a coil 90" mounted upon a ledge 93 fastened to the top inner edge 410 of the segment 41 and a core 83 mounted within the field of coil 9i)" and over the end portion 47b. The pawl-like element 47 has its portion 47b" narrower than the corresponding portion of the previously described pawl-like elements. This is done to make that portion relatively light compared with the portion 47a" so that when the drum 4th is rotating at high speed, the heavier weight of the portion 47a" will cause it, as well as the element 42", to be flung outwardly whereupon 47a will engage the retaining ring of the element 42" as shown in FIG. 7. Consequently, the element 42" will be in the punch position in the absence of a signal applied to the coil $6. The pawl portion 47b" is also magnetized to be a south pole and the coil 91')" is so arranged that its lower end is also a soul; pole when energimd. Thus, when the coil 91? is energized by a signal from the leads 32, which may be connected to wipers or contacts (not shown) such as brushes which engage appropriately placed slip rings, the portion 47b will be repelled thereby disengaging the portion 47a" from the retaining ring and allowing the element 42" to be moved inward when it encounters the medium as. In this embodiment it is seen that the no-punch position is produced in the presence of the energizing signal.

Another embodiment is shown in FIG. 8 which also has an actuating electroma let associated with each of the punch subassemblies. The pawl-like member may be exactly the same configuration as the one shown in FIG. 7 and may have its narrower end similarly magnetized. Since the lower end of the pawl member is heavier, it will normally be urged outward by centrifugal force close to the retaining ring of member 42" when the drum is rotating at high speed and therefore will prevent substantial inward movement of the member 42. The coil 96 is mounted on an L-shaped bracket 1% fixed to the surface 41a and its core 88 serves in place of the pin 51 to limit the clockwise movement of 4%. When it is desired to punch the medium, she normal position of 47" will be the one to accomplish this function. When it is not desired to perforate the medium, a signal will be applied to the coil 99" which thereupon pulls the narrower end downward toward the core thereby releasing the pawl and enabling the element 42 to be pushed inward by contact with the medium. In this case also, the leads 32 from the coil would be connected to appropriate brushes (not shown) for engaging slipr-ing type members (not shown) within the interior of the drum.

There is also the possibility of having not just one bank of electromagnets as in FIG. 1, but two or more located at different angular positions within the drum 49 so that particular ones of the pawl members may be actuated well in advance of entering the punching region without the necessity for providing individual electromagnets for each punch subassembly.

It is not essential that the pawl-like mechanism have any particular configuration but only that it be mounted independently of the electromagnets and in close proximity thereto. It should alseo be as light as possible to enable quick response yet strong enough to withstand pressure on its tip portions exerted by the element 42 when it is pushed inward.

Other Applications The invention may also be used in applications other than perforating applications. One such use is for making imprints or impressions of characteris on certain media. There could be a horizontal apertured member in which a selected number of elongated printing members (similar to the elements 42) are disposed. On the lower ends or" these printing members there could be difierent type faces for different desired characters. Above these printing elements there could be an array of corresponding pawl-like elements and above the latter a number of electromagnets would be disposed. The medium would be fed past the lower ends of the printing members with an intermittent motion. Below the medium there would be disposed a carbon paper (or equivalent) element with the carbon side facing up. A resilient member would be below the carbon paper and would be moved up intermittently to press the carbon paper against the medium whereupon those of the printing member-pawl-electromagnet assemblies which were energized to keep the elongated member from moving upward would cause a carbon impression to appear on the lower side of the medium. On the other hand, those assemblies not energized would permit the elongated member to move upward and thus there would not be suiiicient pressure from it through the medium onto the carbon side to make a distinguishable imprint.

It is also possible to use some of the features of the apparatus herein described for sensing data in the form of perforations in previously perforated media. For this purpose, the pawl elements need not be used, but there would be a physical, magnetic, or electrical signal or condition produced whenever the medium to be sensed, because of the absence of a perforation, forced the elon gated member (similar to elements 42) to move inward (i.e., in a direction away from the medium). For example, the innermost end of the elongated member could be magnetized and disposed within a coil so that it would induce a signal in the coil upon being forced inward. The coil could be connected to slip rings and an output circuit could utilize the signal. Alternatively, a direct electrical connection could be made by the inward movement of the elongated element. In any case the rapidity of processing by the countenrotating drums could be taken advantage of.

Still other arrangements are possible for producing switching actions or signals in response to the position of the elongated member as influenced by the presence or absence of perforations in the medium. For example, a switching or signalling action might be produced in the apertured die drum when the element i2 penetrated an aperture in the card. The signal could be produced by an actual make-break type of operation, or by induction within a coil located in or near the aperture in the die drum, for example.

Other applications of the present invention will occur to those skilled in the art. Consequently, I desire my invention to be limited only by the claims presented herein.

I claim:

1. Perforating apparatus comprising: first and second generally drum-shaped members, means for driving said first and second members at high speed in synchronism in opposite rotary directions, a selected number of perforating elements disposed within apertures in said first member and constructed and arranged to move axially inwardly or outwardly of said first member, said elements normally being urged to their most outward positions under araaaea the influence of the centrifugal force generated by said high speed rotation, a selected number of pivotally movable pawl-like elements fixedly mounted on said first member in proximity to selected ones of said perforating elements, a selected number of electromagnetic means associated with but unconnected to selected ones of said pawl-like elements for moving selected ones of said latter elements to a predetermined pivotal position in response to electrical signals applied to said electromagnetic means, said predetermined position being such as to oppose substantial inward axial movement of said perforating elements, said pawl-like elements, also being constructed so as to be urged by said centrifugal force, when said drummembers rotate, to a different pivotal position which does not oppose substantial inward movement of said perforating elements, said second drum member having a selected number of die apertures t erein positioned and arranged to be engaged by corresponding ones of said perforating elements in their outward positions.

2. Perforating apparatus comprising: first and second drum-shaped members, means for driving said first and second members at high speed and in synchronism in opposite rotary directions, said first drum member having a selected number of apertures therein and a selected number of elongated perforating elements disposed for axial movement within said apertures, said perforating elements normally being urged outwardly when said first member is rotating only by the centrifugal force generated by said high speed rotation, a selected number of pawl-like elements pivotally mounted on said first member in proximity to selected ones of said perforating elements, a selected number of electro-magnetic means disposed within said first member and adapted to be energized by electrical signals applied thereto, said electromagnetic elements being located in proximity to selected ones of said pawllike elements but not connected thereto for pivotally moving, in response to signals applied to said electromagnetic means, selected ones of said pawl-like elements to a predetermined position which prevents substantial inward axial movement of said perforating elements, said pawllike elements, also being constructed so as to be urged by said centrifugal force, when said drum-members rotate, to a difierent pivotal position which does not oppose substantial inward movement of said perforating elements, said second drum like member having a selected number of die apertures therein positioned and arranged to be engaged by corresponding ones of said perforating ele ments when the latter are prevented from substantial inward movement by action of said pawl-like elements.

3. The perforating apparatus according to claim 2 wherein said perforating elements include means toward their inner ends for limiting the outward movement of said elements and wherein said pawl-like elements are mounted to pivot about pivot pins disposed on said first membersubstantially parallel to the axis of said first member.

4. The perforating apparatus according to claim 2 wherein means are provided for collecting punched-out material produced by the co-action of said perforating elements and their associated die apertures within second drum-shaped member. I

5. Perforating apparatus comprising first and second drum-shapedmembers, said first drum-shaped'rnember having an apertureiri one end thereof, means for driving said first and second members at high speed and in synchonism in opposite rotary directions, said first drum' memher having a selected number of a ertures therein and a selected number 'of elongated perforating elements disposed for axial movement within said apertures, said perforating elements normally being urged outwardly when said first memberis rotating only by the centrifugal force generated by said high speed rotation, a selected number of pawl-like elements pivotally mounted on saidlfirst member: in proximity to selected ones of said perforating elements, a selected number of electromagnetic means disposed within said first member and adapted to be energized by electrical signals applied thereto, said electromagnetic elements being located in proximity to selected ones of said pawl-like elements but not connected thereto for pivotally moving, in response to signals applied to said electromagnetic means, selected ones of said pawl-like elements to a predetermined position which prevents substantial inward axial movement of said perforating elements, a rigid, substantially hollow member which passes through said aperture in said first drum-shaped member and is partially disposed substantially parallel to the longitudinal axis thereof, said electromagnetic elements being disposed on means fixedly connected to said hollow memher, said electromagnetic elements having leads connected thereto which pass through said hollow member to a signal source located externally of said first drum member, and said second drum-like member having a selected number of die apertures therein positioned and arranged to be engaged by corresponding ones of said perforating elements when the latter are prevented from substantial inward movement by the action of the said pawl-like elements.

6. Perforating apparatus comprising: a first hi h speed rotating member which includes a selected number of perforating elements disposed therein capable of moving substantially axially outwardly and inwardly of said first rotary member, said perforating elements normally urged to their most outward positions under the influence of the centrifugal force generated by said high speed rotation, a selected number of pawl-like elements in proximity to selected ones of said perforating elements, each of said pawl-like elements being constructed and arranged to move to at least two positions in one of which it prevents substantial inward axial movement of the associated one of said perforating elements and in the other of which it permits inward axial movement of said associated perforating element, said pawl-like elements being constructed and arranged to be moved in response to said centrifugal force to the position in which they prevent substantial inward movement of said perforating elements, a selected number of electromagnetic means associated with but unconnected to predetermined ones of said pawl-like elements for determining which of said positions said associated pawl-like element will assume, said electromagnetic means being constructed and arranged'in response to signals applied thereto, to cause said pawl-like elements to move to the position in which they permit inward movement of said perforatin elements, a second high speed rotating member having a selected number of apertures therein positioned and arranged to be engaged by corresponding ones of said perforating elements when prevented from inward axial movement by said pawl-like elements.

7. Perfor ting apparatus comprising: a first high speed rotating member which includes a selected number of perforating elements disposed therein capable of moving substantially axially outwardly and inwardly of said first rotary member, said perforating elements normally being urged to their most outward position under the influence of the centrifugal force generated by said high speed rotation, a selected number of pawl-like elementsin proximity to selected ones of said perforating elements, each of said pawl-like elements being constructed and arranged to move to at'least two positions in one of which it prevents substantial inward axial movement of the asso-' ciated one of said perforating elements and in the other of which it permits inward axial movement of said associated perforating element, said pawl-like elements bein magnetized and being constructed and arranged to' of 'said positions said associated pawl like element will assume, said electromagnetic means being constructed and arranged to produce, in response to signals applied thereto, magnetic fields which repel said associated pawl-like elements thereby moving the latter to the position in which they permit inward axial movement of said perforating elements, a second high speed rotating member having a selected number of apertures therein positioned and anranged to be engaged by corresponding ones of said perforating elements when prevented from inward axial movement by said pawl-like elements.

References Cited in the file of this patent UNITED STATES PATENTS Sally May 25, Stram Sept. 4, Johnston Oct. 28, De Boo May 31, Tailleur May 30, Glattli June 20,

Claims (1)

1. PERFORATING APPARATUS COMPRISING: FIRST AND SECOND GENERALLY DRUM-SHAPED MEMBERS, MEANS FOR DRIVING SAID FIRST AND SECOND MEMBERS AT HIGH SPEED IN SYNCHRONISM IN OPPOSITE ROTARY DIRECTIONS, A SELECTED NUMBER OF PERFORATING ELEMENTS DISPOSED WITHIN APERTURES IN SAID FIRST MEMBER AND CONSTRUCTED AND ARRANGED TO MOVE AXIALLY INWARDLY OR OUTWARDLY OF SAID FIRST MEMBER, SAID ELEMENTS NORMALLY BEING URGED TO THEIR MOST OUTWARD POSITIONS UNDER THE INFLUENCE OF THE CENTRIFUGAL FORCE GENERATED BY SAID HIGH SPEED ROTATION, A SELECTED NUMBER OF PIVOTALLY MOVABLE PAW-LIKE ELEMENTS FIXEDLY MOUNTED ON SAID FIRST MEMBER IN PROXIMITY TO SELECTED ONES OF SAID PERFORATING ELEMENTS, A SELECTED NUMBER OF ELECTROMAGNETIC MEANS ASSOCIATED WITH BUT UNCONNECTED TO SELECTED ONES OF SAID PAW-LIKE ELEMENTS FOR MOVING SELECTED ONES OF SAID LATTER ELEMENTS TO PREDETERMINED PIVOTAL POSITION IN RESPONSE TO ELECTRICAL SIGNALS APPLIED TO SAID ELECTROMAGNETIC MEANS, SAID PREDETERMINED POSITION BEING SUCH AS TO OPPOSE SUBSTANTIAL INWARD AXIAL MOVEMENT OF SAID PERFORATING ELEMENTS, SAID PAW-LIKE ELEMENTS, ALSO BEING CONSTRUCTED SO AS TO BE URGED BY SAID CENTRIFUGAL FORCE, WHEN SAID DRUMMEMBERS ROTATE, TO A DIFFERENT PIVOTAL POSITION WHICH DOES NOT OPPOSE SUBSTANTIAL INWARD MOVEMENT OF SAID PERFORATING ELEMENTS, SAID SECOND DRUM MEMBER HAVING A SELECTED NUMBER OF DIE APERTURES THEREIN POSITIONED AND ARRANGED TO BE ENGAGED BY CORRESPONDING ONES OF SAID PERFORATING ELEMENTS IN THEIR OUTWARD POSITIONS.

Images