GB2378675A

GB2378675A - Paper perforating apparatus

Info

Publication number: GB2378675A
Application number: GB0212952A
Authority: GB
Inventors: Christopher Patrick Ford; Jonothan Maxwell Hamer
Original assignee: Individual
Current assignee: Individual
Priority date: 2001-06-06
Filing date: 2002-06-06
Publication date: 2003-02-19
Also published as: GB0212952D0; GB0113702D0

Abstract

An automated paper punch is disclosed wherein a set of preferably auger tipped single tip 64 drills 46 are lowered, as a platform 16 is lowered, onto a constrained 50 heap of one or more sheets of paper 70 which the drill bits 46 perforate and, storing paper swarf 68 in their flutes 72, retain the swarf 68 in through-transit of the perforated paper 70 and deposit the paper swarf (68) into a subtending waste receptacle 66 beneath the perforated paper. Methods of moving the drills 46 includes cams 36 and springs 22, one or more mono-directional and bi-rotations motors 30 and gearboxes 34, racks 134 and gears 30A, 34B, lead screw apparatus 132, limit switches 56 and cross-over switches 126. An alternative form of drill 46 moving is provided in the form of a platform support frame 140 whose geometry can be forcefully and firmly changed by screwing in or screwing out a threaded bolt 148 to cause the drill bits 46 to approach or withdraw from the paper.

Description

Paper Perforatincr Apparatus The present invention relates to machines for perforating one or more sheets of paper to provide holes allowing the paper to be placed into a ring binder or otherwise bound by the provision of hoops or pillars passing through the perforations.

The normal method of perforating one or more sheets of paper is to employ a punch and die. The paper is placed on a support surface which has the die hole passing there through. The punch element is brought down by the force on a lever so that the punch passes through the sheets of paper and into the die hole for the disc of paper, which has been cut out, to be deposited in a closed receptacle. A problem exists with such machines. There is a distinct limit to the number of sheets of paper which simultaneously may be punched. As the cutting tips of the punch become blunt, so the number of sheets of paper which may simultaneously be cut decreases. The present invention seeks to provide a paper perforator which does not depend upon the sharpness of a punch to determine the number of sheets of paper which may simultaneously be perforated.

In an attempt to increase the number of sheets of paper which simultaneously can be perforated, the punches have been rendered hollow, being forced against an anvil rather than into die holes, so that the discs of paper, which are cut, accumulate up inside the length of the hollow punch and eventually are forced from the top end thereof. Punched paper discs are very difficult to contain and clean. This prior art solution allows more sheets of paper simultaneously to be perforated, but has the disadvantage of inducing bad house-keeping. The present invention seeks to provide an apparatus, capable of perforating many sheets of paper at the same time, while retaining any waste generated thereby.

When punching thick stacks of paper, the force required on the punch elements is considerable. This is generally provided by means of a lever, operated by hand, pushing down on the punch elements. As the

stack of paper becomes thicker, so the amount of force required increases. Paper punches for thick stacks of paper generally have long levers of considerable mechanical strength. The amount of force, required by an individual to operate such a punch, is often beyond people who are frail, suffering from muscular difficulties, suffering from arthritis, or who are simply unable to bring themselves high enough above the lever to force their body weight onto the lever. The present invention seeks to provide an apparatus for perforating paper which is fully self-powered and requires zero physical effort from the user.

It is known, in the prior art, to employ rotating drills to perforate paper. An example of such use is shown in United States patent 3718404. In this apparatus, an industrial machine is shown where drills ascend into a stack of paper, the paper being moved sideways by conveyor belts, the waste from the drilling operation not being contained and the safety aspects, from a modern point of view, being extremely poor. The present invention seeks to provide an apparatus, using drilling to perforate paper, suitable for an office or domestic environment rather than an industrial environment, compact, and meeting all requirements of health and safety legislation.

The present invention consists in an apparatus for perforating paper comprising: a platform for supporting a drill, means to rotate the drill, and means to cause the platform and the stack of one or more sheets of paper to approach one another for the drill to penetrate and perforate the one or more sheets of paper.

The invention also provides an apparatus where the paper is clamped prior to the drill engaging the paper.

The present invention also provides an apparatus where the drill retains paper swarf in the flute thereof to be deposited, on completion of perforation of the paper, into a waste receptacle.

The present invention also provides that the means for causing the relative movement between the platform and the paper comprises a rotatable cam pressing against an upper member, and spring restoring force to return the platform after the paper has been perforated.

The present invention also provides an apparatus where the means for rotating the drill and the means for rotating the cam include a common motor powering a gear box with output suitable to each purpose.

The present invention also provides an apparatus where the drill is one of a plurality of spaced drills.

The present invention also provides an apparatus wherein the means for rotating the drill and the means for creating relative movement between the platform and the paper can perform a single drilling cycle, starting from an initial position, the platform moving to perforate the paper, and then returning to the initial position.

The present invention also provides an apparatus wherein the movement of the platform is controlled by a limit switch.

The present invention also provides an apparatus wherein the movement and direction of the platform are controlled by one or more cross over switches.

The present invention also provides an apparatus wherein the drill is a single flute auger tipped drill.

The invention further provides an apparatus wherein the means for causing said platform and said stack of one or more sheets of paper to move towards each other can comprise: first means, operative to alter the configuration of a platform-supporting frame to cause said platform and said stack of one or more sheets of paper to move from a start position towards each other; and second means, operative to restore the configuration of said platform-supporting frame to cause

said platform and said stack of one or more sheets of paper to return to said start position.

The invention also provides an apparatus wherein said first means comprises a screw, and means to rotate said screw to reduce the linear distance between two members of said frame; and wherein said second means comprises said screw, and means to counter rotate said screw to restore the linear distance between said two members of said frame.

The present invention, still further, provides an apparatus wherein the means for moving the platform comprise a rack or a lead screw.

The present invention also provides an apparatus wherein a cycle of operation to perforate paper is initiated by a single and brief operation of a push button.

The invention is further explained, by way of example, by the following description, taken in conjunction with the appended drawings, in which: Figure 1 show an isometric view of the essential components of a first embodiment of the invention.

Figure 2 shows a semi-cross sectional view of the apparatus of figure 1, when assembled, on the plane 58 looking in the direction of arrow 60.

Figure 3A shows a side view of the preferred drill in the present invention, and figure 3B shows further detail of the drill of figure 3A looking in the direction of arrow 82.

Figure 4 is a cross sectional view of the apparatus of figures 1 and 2 when the cam has pushed the platform to it's lowest excursion.

Figure 5 is an isometric view of the apparatus of figures 1,2 and 4, contained within a housing, figure 5 also showing means whereby the apparatus may be powered and emptied of paper swarf.

Figure 6 is a circuit, capable of use with the first embodiment of the invention, which executes a single cycle of paper perforating operation.

Figure 7 is an isometric view of an second embodiment of the invention where more than one motor is used to achieve the various functions.

Figure 8 is an electric circuit suitable for use with the embodiment of figure 7.

Figure 9 is a view, similar to that figures 2 and 4, showing a third embodiment of the invention where reciprocating action of the cam and reverse action of the drills is achieved.

Figure 10 is a circuit, suitable for use with the embodiment of figure 9.

Figure 11 is an isometric view of a fourth embodiment of the invention where the cam is replaced by a lead screw.

Figure 12 is an isometric view of a fourth embodiment of the invention where the cam is replaced by use of a rack.

Figure 13A shows a view from above of a sixth embodiment of the invention.

Figure 13B shows a view of the sixth embodiment of the invention looking in the direction of arrow 136 on figure 13A.

Figure 13C shows a view of the sixth embodiment of the invention looking in the direction of arrow 138 shown in figure 13B.

And

Figure 13D shows a plan view, seen from above, of the platform support frame 140 and its attendant mechanisms, pointed out in Figures 13B and 13D.

Attention is drawn to figure 1 which shows an isometric projection of the principle working parts of the present invention.

A frame 10 comprises a base plate 12, a top plate 14, and a platform 16 arranged on vertical pillars 18 such that the base plate 12 and the top plate 14 are held a fixed distance apart while the platform 16 is able to move up and down on the pillars 18, as indicated by arrow 20 under the restorative force of pillar springs 22 disposed about the pillars 18 between the platform 16 and the base plate 12.

Adjustable paper guides 24 are provided on the base plate 12 to accept and position one or more sheets of paper. Vertically aligned drilling apertures 26 are provided both on the base plate 12 and the platform 16 spaced by the distance apart that it is desired to punch holes in the one or more sheets of paper. Clamp pin apertures 28 are provided in the platform 16.

Drawing attention to that portion of figure 1 where the platform 16 is shown exploded away from the main frame 10, a motor 30 vertically spaced from the top surface of the platform 16 by a motor support pillar 32 drives a gear box 34 having two outputs, a first to rotate a cam 36, at around 15rpm, as indicated by arrow 38, and a second driving a pulley (hidden in this drawing) to move a belt 40 turning drill pulleys 42 on drill support columns 44 to rotate drills 46 as indicated by arrows 48 at around lOOOrpm. A paper shield 50 is supported on clamp pins 52 beneath the platform 16 under the resilient force of clamp pin springs 54. The gearbox 34 has an upper surface 55 which rests against the underside of the top plate 12 when the platform 16 is in its highest position. A limit switch 56 is mounted (on the gearbox 34, in this example) to be operated when the upper surface 55 of the gearbox 34 comes to rest against the underside of the top plate 14.

Attention is drawn to figure 2 showing a view, in partial cut away, through the plane 58, shown in dotted outline in figure 1, looking in the direction of arrow 60.

Figure 2 shows the platform 16 in its uppermost position. The motor 30 and gear box 34 have rotated the cam 36 to allow the platform 16 to rise until the upper surface 55 of the gear box 34 contacts the under side 62 of the top plate 14, at which point the limit switch 56 is operated. As will later be explained, this is a rest point for the mechanism. The motor support pillar 32 must be sufficiently high for the cam 36, when in the position shown in figure 2, not to contact the upper surface 63 of the platform 16. This avoids jamming.

The drills 46, supported in the drill support columns 44 and turned by the drill pulleys 42, have drill tips 64 which are completely contained within the thickness of the paper shield 50, supported beneath the platform 16 by the clamp pins 52 under the resilience of the clamp pin springs 54. The base plate 12 is shown provided with a waste receptacle 66 for retaining paper swarf 68 generated by the paper drilling process. A stack of paper 70 is shown in position, ready to be drilled, prior to commencement of the paper drilling process.

Attention is drawn to figures 3A and 3B showing details of the drill 46 and the drill tip 64. The drill 46 has a single flute 72 terminating in a sharp auger tip 74, which marks the commencement of the flute 72. The auger tip 74 is situated at the same diameter as the shank 76 of the drill 46 so that, as the auger tip 74 cuts through paper 70 when the drill 46 rotates as indicated by arrow 78 and is moved forward as indicated by arrow 80, the hole in the paper 70 which it makes is exactly the same diameter as the shank 76 of the drill 46. The width L of the flute 72 is in the region of 8.5mm. The depth D of the flute 72 is in the region of 3mm. As the drill 46 advances, the paper swarf 68, even for the maximum thickness of stack of paper 70, is entirely contained within the flute 72. The overall extent E of the tip 64 of the drill 46 (here

dimensioned to indicate the (invisible) termination of the flute 72) is such that, in the situation shown in figure 2, the extent E of the tip 64 of the drill 46 is less than the thickness of the paper shield 50. The auger tip 74 is situated above the bottom of the paper shield 50 and the entire flute 72 is also contained within the thickness of the paper shield 50. The diameter of the drilling apertures 26 is just enough to provide clearance for the drill 46.

Figure 3B shows a view of the drill 46 and its tip 64 looking in the direction of arrow 82. The drill 46 is here shown at half the scale of figure 3A. The auger tip 74 is the leading point of a tapered section 84 which wraps around the drill tip 64, at the same diameter as that of shank 76, rather in the shape of a bishops mitre, to consolidate and support cut paper 70 as the drill 46 passes there through.

Attention is drawn to figure 4 showing the apparatus of figure 2 when the drills 46 have penetrated the stack of paper 70. The cam 36 is in its highest position so that the underside 62 of the top plate 14 is as far away as it can get from the upper surface 55 of the gear box 34, the limit switch 56 no longer being operated. The paper shield 50, as the platform 16 descends against the pressure of the pillar springs 22, first encounters the upper surface 86 of the stack of paper 70. As the cam 36 continues to be rotated by the motor 30 and gear box to push upon the underside 62 of the top plate 14 to cause the platform 16 to descend, the paper shield 50 stops at the surface 86 of the stack of paper 70 and applies clamping pressure to the stack of paper 70 under the force of the clamp pin springs 54. The drill tips 64 clear the shielding of the paper shield 50 and cut through the stack of paper 70, making a hole of uniform diameter, the same as that of the drill 46. The clamp pins 52 slide relatively upwards in the platform 16 through the clamp pin apertures 28. The paper swarf, 68, as earlier described with reference to figures 3A and 3B, remains trapped within the flute 72 of each drill 46. As the drill tips 64 clear the stack of paper 70, they encounter the drilling apertures 26 in the base plate 12, which are also a close clearance fit to the diameter of the drills 46.

The paper swarf 68 is therefore retained within the flute 72 of each drill 46 until the drill tip 64 has passed entirely beneath the base plate 12 into the waste receptacle 66, where the paper swarf 68 is dropped and retained for later disposal. Having reached the furthest point where the cam 36 is at its highest, the cam 36 continues to be rotated by the motor 30 and the gear box 34 to return to the position shown in figure 2.

In order for the mechanism not to jam (caused by the cam 36 not having sufficient room to complete a rotation when the paper shield 50 is on the maximum thickness of stack of paper 70 the apparatus is designed to perforate), the available movement of the paper shield 50, relative to the platform 16, must equal or exceed the sum of the thickness of the paper shield 50, the thickness of the base 12, and the thickness of the maximum stack of paper 70. The throw of the cam 36 must not be sufficient to force the paper shield 50 hard against the base plate 12, but must be enough to cause the drill tips 64 completely to enter the receptacle 66.

Attention is drawn to figure 5, showing the apparatus of the previous figures encased in a housing 88. The adjustable paper guides 24, otherwise shown in figure 1, are extended beyond the housing 88 to be adjustable as indicated by directional arrows 90 to accommodate paper 70 to be punched. The paper 70 is inserted into an access gap 92 as indicated by arrow 94. A platform 96 is provided for the support of paper 70 as it is punched. The platform 96 also serves a battery housing where batteries or cells can be changed via a battery access hatch 98. A waste hatch 100 or drawer, representing at least part of the waste receptacle 66, can be opened as indicated by arrow 102 to allow removal of paper swarf 68. An alternative source of power, rather than batteries, is provided in the form of an AC power supply 104 which plugs into the housing 88 to power the punch, deriving it's power from an AC power source 106.

The AC power supply 104 is preferred to be external to the housing 88 so that it does not provide a heat source having the possibility of igniting the paper swarf 68. If suitable precautions are taken, of course, the AC power supply 104 can be accommodated within the

housing 88. A push button 108 is momentarily depressed, as indicated by arrow 110 to cause the punch to go through a cycle of operation.

Attention is drawn to figure 6, showing the electric circuit of the embodiment of the invention shown in figures 1 to 5. The AC power supply 104, powered by the AC power source 106, is selectable exchangeable, by use of a switch 112, with a battery 114 to be the power supply for the punch. The switch 112 can be a discreet user operable switch or can be a jack switch, automatically operated when the AC power supply 104 is plugged into the enclosure 88. The selected power source 104 114 is provided as input to the limit switch 56, in which spring 116 closes electrical contact 118 unless an operating rod 120 is depressed (by the underside 62 of top plate 14 as indicated by arrow 122). Push button 108, when pushed as indicated by arrow 110 (otherwise seen in figure 5), momentarily shorts out the limit switch 56. Both the limit switch 56 and the push button 108 are capable of powering the motor 30.

The manner of operation is as follows. With the cam 36, as shown in figure 2, the limit switch 56 has the operating rod 120 depressed, so that the electrical contact 118 is broken. The limit switch 56 therefore provides no power to the motor 30. When the push button 108 is depressed, the limit switch 56 is bypassed by the contacts of the push button 108 and electrical energy is delivered to the motor 30, which rotates the cam 36. After a short time (a fractional second) the cam 36 will have moved sufficiently for the limit switch 56 to have moved away from the position where the operating rod 120 is depressed by the underside 62 of the top plate 14. The operating rod 120 is then pushed back by the spring 116 so that the electrical contact 118 is made. This also provides electrical energy to the motor 30. When the push button 108 is released, the limit switch 56 continues to supply electrical power to the motor 30. The motor 30 turns the drills 46 and the cam 36 until the limit switch 56 once again is operated by the operating rod 120 engaging the underside 62 of the top plate 14 and opening the contacts 118. A momentary push of the push button 108 thus initiates a self-terminating single

cycle of descent and re-ascent of the platform 16, the drills 46 rotating all the while.

Attention is next drawn to figure 7 showing a second embodiment of the present invention where separate electrical motors are used. A main motor 30 is mounted on the platforms 16 to rotate the drills 46. One or more secondary motors 30A (each with its own gear box 34A) rotate a corresponding number of cams 36. In this embodiment the functions of rotating the drills 46 and operating the cam 36 are separated. Attention is drawn to figure 8 showing an electrical circuit for operating the embodiment of figure 7. The circuit of figure 8 is exactly the same as the circuit of figure 6, with the exception that the one or more secondary motors 30A are wired in parallel with the main motor 30.

Attention is drawn to figure 9 showing a cross sectional view of a third embodiment of the present invention. It is essentially the same as the embodiment shown in figure 4, with the exception that a limit pillar 124 is mounted on the base plate 12 and a lower cross over switch 126 is mounted beneath the platform 16. The lower cross over switch 126 is operated by contact with the limit pillar 124 when the platform 16 is at its lowest position. An upper cross over switch 127 is mounted level with the limit switch 56 to be operated when the platform 16 is in the same position where the limit switch 56 is operated. The cam 36 of figure 4 is replaced by a reversing cam 36A which rotates bidirectionally as indicated by arrow 128. As will be shown in figure 10, the combination of the limit switch 56 and the upper and lower cross over switches 126 127 permits the motor 30 to run first in one direction to cause the platform 16 to descend, and thereafter in the opposition direction to cause the platform 16 to ascend and stop.

Attention is drawn to figure 10 showing a circuit suitable for use with the embodiment of figure 9. A modified limit switch 56A has two sets of contacts as opposed to the single set of contacts show in figures 6 and 8. Likewise a modified push button 108A has two sets of contacts as opposed to the single set of contacts shown in

figures 6 and 8. The modified limit switch 56A now makes and breaks connection to both the positive and negative supplies from the selected power source 104 114. The modified push button 108A shorts (bridges) the modified limit switch 56A on its positive and negative supplies. The actions of the modified limit switch 56A and of the modified push button 108A are exactly the same as that described with reference to figures 6 and 8, the momentary depression of the modified push button 108A causing the motor 30 to commence moving so that the underside 62 of the top plate 14 ceases to operate the modified limit switch 56A which takes over the supply of power to the motor 30. When the reversing cam 36A returns the platform 16 to its highest position, the modified limit switch 56A stops supply of all power to the motor 30 so that the mechanism remains in its rest position awaiting a further depression of the modified push button 108A.

Cross over switches 126 and 127 are"push to change" double pole double throw switches. When activating rod 130 is depressed, the twin set of contacts snap from one position to the other. When activating rod 130 is depressed again, the two sets of contacts snap back from the other position to the one. This cycle can be performed endlessly. The lower cross over switch 126 and the upper cross over switch 127 are wired such that, when the modified push button 108A is momentarily depressed and the modified limit switch 56A also provides power for the motor 30, the motor 30 rotates in such a manner that the platform 16 commences to descend. As the lower cross over switch 126 encounter the limit pillar 124, the activating rod 130 is depressed, the two sets of contacts in the lower cross over switch 126 are snapped to the other position, the electrical power to the motor 30 is reversed in polarity and the motor 30 reverses in direction of turn. As the limit switch 56 and the upper cross over switch are again activated by their mechanical contact with the underside 62 of the top plate 14, the limit switch 56 stops the motor 30, and, at the same time, the upper cross over switch 127 crosses over the power supply connections to the lower cross over switch 126 so that, when the modified push button 108A is again

pressed, the motor 30 will turn in a direction to cause the platform 16 to descend. This cycle is endlessly repeatable.

Attention is drawn to figure 11 showing a fourth embodiment of the present invention. The platform 16 is shown part way through its travels between the base plate 12 and the top plate 14. A secondary motor 30A drives a first modified gear box 34A which turns an internal threaded wheel (for example, using a worm drive) to urge the platform 16 up and down the threads of a lead screw 132 affixed on the base plate 12, affixed to the top plate 14, or affixed to both the top plate 14 and the base plate 12. The secondary motor 30A is wired in parallel with the main motor 30 which rotates the drills 46 in the circuit shown in figure 10. Because the cam 36, 36A has been eliminated, the need for space (to give sufficient throw to the cam 36,36A) between the platform 16 and the top plate 14, when the platform 16 is in its uppermost position, is considerably reduced resulting in a much shorter main motor 30, the elimination of the motor support pillar 32 and much shorter drill support columns 44. The limit switch 56 and the upper cross over switch 127 are mounted directly on to the upper surface of the platform 16 and, together, provide the means whereby the platform 16 rests proximate to the underside 62 of the top plate 14.

Attention is drawn to figure 12, showing a fifth embodiment of the invention. Figure 12 is substantially the same as figure 11, and operates in a similar manner with the exception that the combination of the first modified gear box 34A and the lead screw 132 is replaced by a second modified gear box 34B and a vertical rack 134 passing there through. Within the gear box 34B is a gear which engages the rack 134 to urge the platform 16 up and down between the top plate 14 and the base plate 12. The rack 134 can be attached to the base plate 12, attached to the top plate 14, or attached both to the base plate 12 and top plate 14.

The embodiments shown in figures 11 and 12 are suitable for use with the circuit shown in figure 10, with the understanding that, as a pair of motors 30,30A are used, the secondary motor 34A is wired in

parallel with the main motor 30. It is also to be understood that the use of racks 134 or lead screws 132 is also possible with the embodiment shown figures 1,2 and 4, the rack 134 or lead screw 132, or other means, replacing the cam 36, the gear box 34 being adapted to accept the rack 134, lead screw 132 or other means, and the circuit of figure 10 employed.

The embodiments shown in figures 9,10, 11 and 12, and the combination of the embodiments of figures 2 and 4 employing the circuit of figure 10, provide the considerable benefit that, on the platform 16 being withdrawn from the stack of paper 70, the drills 46 are counter rotated (in the opposite sense to that used to cut the paper 70) so that the drill tips 64 are cleared from the paper 70 in a beneficial manner more commonly used in drilling, and for which all types of fluted drills 46 are adapted. Any paper swarf 68 is brushed from the flute 72 and falls into the receptacle 66.

Attention is drawn to the portions of Figure 13. Figure 13A shows a view from above of a sixth embodiment of the invention. Figure 13B shows a view of the sixth embodiment of the invention looking in the direction of arrow 136 on figure 13A. Figure 13C shows a view of the sixth embodiment of the invention looking in the direction of arrow 138 shown in figure 13B. Figure 13D shows a plan view, seen from above, of the platform support frame 140 and its attendant mechanisms, pointed out in Figures 13B and 13D. All of these figures are described together.

The top plate 16 is omitted. Instead, the platform 14 supports the drill pulleys 42 and the drill turning belt 40. Supported therebeneath is a common motor and gearbox 142 which turns, through one gearbox outlet, a right angle gear mechanism 144 which drives the rotation of the drill support columns 44 turning the drills 46. The common motor and gearbox 142 turns, through another gearbox outlet, coupled through a drive belt 146, a threaded bolt 148 which passes through a freely rotating support 150 through a first spacing bar 152A and a threaded area 151 in a second spacing bar 152B. The first spacing bar 152A is at a fixed pair of pivots 154 fixed to an upper

slide frame 156. A second spacing bar 152B is at a moveable pair of pivots 158 which are free to move in the sliding pivot aperture 160 of the upper slide frame 156. First 162 and second 164 sides of the platform support frame 140 respectively comprise outer lever arms 166 and inner lever arms 168. The top end of each inner lever arm 168 is rotatably affixed to the platform support frame 140 via the fixed pivot 154. The top end of each outer lever arm 166 is rotatably affixed in the sliding pivot aperture 160 on the moveable pivot 158. A lower slide frame 172 having a lower sliding pivot aperture 174 and a lower fixed pivot 176 is a mirror image, in a horizontal plane, of the upper slide frame 165, and is affixed to the base plate 12. Each inner lever arm 168 has its lower end affixed at the lower sliding pivot 176 which is constrained to move in the lower sliding pivot aperture. The lower end of each outer lever arm 166 is constrained to rotate about the lower fixed pivot 176. The inner lever arms 168 and the outer lever arms 166 pivot about a common axis 173. As the threaded bolt 148 is rotated by the combined gearbox and motor 142 in a first direction, the distance between the spacing bars 152A 152B increases (from a start position) and the drills 46 are forcibly moved towards and through the level of the base plate 12 to perform paper perforation and swarf disposal, as earlier described. To withdraw the drills 46 back to their start position, the combined gearbox and motor 142 is rotated in the opposite direction to cause the distance between the spacing bars 152A 152B to decrease for the platform support frame 140 to withdraw the drills 46 and to unclamp the paper. Means to control the fact of movement, sense and direction of movement of the common motor 142 has already been described with reference to Figure 10, where a reversing mechanism employing limit switches and power supply polarity reversing switches is shown, in a manner which is equally applicable to the embodiment of Figure 13A to 13D. The invention and various embodiments will also encompass any operating control mechanism which will function as described.

While the cam 36,36A has been shown, in the foregoing examples, as having an eccentrically rotated circular or semi-circular profile,

it is to be understood that other shapes of cam 36,36A may also be employed in the present invention.

Whereas the cams 36,36A, rack 134 and lead screw 132 have been shown as means for causing the platform 16 to move up and down between the top plate 14 and the base plate 12, it is to be understood that any other suitable means can be used within the present invention, such suitable means including, but not being limited to, belts and pulleys, winding and unwinding of bands and so on. The rack 134 and the lead screw 132 have, in the previous examples, been shown as separate items. It is to be appreciated that these features may be included as moulded projections on the interior surface of the housing 88 shown in figure 5, or as indentations in the vertical pillars 18.

While the preferred drill tip 64 has been shown to be a single flute 72 auger tip 74 drill of a specific and advantageous design, it is to be appreciated that other forms of drill, with different tips and one or more flutes, can also be employed in the present invention.

While the electrical circuits for the various embodiments have been shown working on DC current, it is to be appreciated that, especially the first embodiment of the invention, is readily adaptable to employ an AC motor 30, which can take the form of an induction motor, the power source 104 114 being replaced by an AC power source.

The invention is further explained and clarified by the following claims.

Claims

CLAIMS 1. An apparatus for perforating paper comprising: a platform for supporting a drill, means to rotate the drill, and means to cause the platform and the stack of one or more sheets of paper to approach one another for the drill to penetrate and perforate the one or more sheets of paper.
2. An apparatus according to claim 1 wherein said platform is static and said stack of paper is operative to approach said drill.
3. An apparatus according to claim 1 wherein said stack of paper is static and said platform is operative to approach said stack of paper.
4. An apparatus, according to any one of the preceding claims, further comprising clamping means, operative to engage and to hold the stack of paper in place prior to the drill engaging the paper.
5. An apparatus, according to any one of the preceding claims, wherein said drill is operative to retain paper swarf in the flute thereof; and further operative to deposit retained paper swarf, on completion of perforation of the paper, into a waste receptacle.
6. An apparatus, according to any one of the preceding claims, wherein said means to cause the platform and the stack of one or more sheets of paper to approach one another comprise a rack in conjunction with a rack gear.
7. An apparatus, according to any one of claims 1 to 5, wherein said means to cause the platform and the stack of one or more sheets of paper to approach one another comprise a lead screw mechanism.

<Desc/Clms Page number 18>
8. An apparatus, according to any one of the claims 1 to 5, wherein said means for causing said platform and said stack of one or more sheets of paper to move towards each other comprises a rotatable cam to be pressed against a static upper member to cause said platform to move away from a start position, means to rotate said cam, and spring restorations means, operative to apply a restoring force to return said platform to said start position after the paper has been perforated.
9. An apparatus, according to claim 8, wherein said means for rotating said drill and said means for rotating said cam comprise a common motor, coupled to power said means for rotating said drill and said means for rotating said cam.
10. An apparatus, according to any one of claims 1 to 5, wherein said means for causing said platform and said stack of one or more sheets of paper to move towards each other comprises: first means, operative to alter the configuration of a platformsupporting frame to cause said platform and said stack of one or more sheets of paper to move from a start position towards each other; and second means, operative to restore the configuration of said platform-supporting frame to cause said platform and said stack of one or more sheets of paper to return to said start position.
11. An apparatus, according to claim 10, wherein said first means comprises a screw, and means to rotate said screw to reduce the linear distance between two members of said frame; and wherein said second means comprises said screw, and means to counter rotate said screw to restore the linear distance between said two members of said frame.
12. An apparatus, according to any one of the preceding claims, wherein said means for rotating said drill and said means to cause the platform and the stack of one or more sheets of paper to approach one another are co-operative to perform a single drilling cycle, starting from an initial position, moving to perforate the paper, and then returning to said initial position.

<Desc/Clms Page number 19>
13. An apparatus, according to claim 12, wherein the extremity of movement of said means to cause said platform and the stack of one or more sheets of paper to approach one another is controllable by a limit switch.
14. An apparatus, according to claim 12 or claim 13, wherein movement and direction are controllable by one or more cross over switches.
15. An apparatus, according to any one of the preceding claims, wherein said drill comprises a single flute auger tipped drill.
16. An apparatus, according to any one of the preceding claims, operative to perform a cycle of operation to perforate paper and operative to initiate said cycle in response to a single and brief operation of a push button.
17. An apparatus, according to any one of the preceding claims, wherein said drill is one of a plurality of spaced drills.
18. A method for perforating paper comprising the steps of: supporting a drill on a platform; rotating the drill in a direction to cut; and causing said platform and the stack of one or more sheets of paper to approach one another for said drill to penetrate and perforate the one or more sheets of paper.
19. A method, according to claim 18, including the steps of keeping said platform static and moving said stack of paper relative to said drill.
20. A method, according to claim 18, including the steps of keeping the stack of paper static and moving said platform relative to said stack of paper.

<Desc/Clms Page number 20>
21. A method, according to any one of claims 18 to 20, including the step of clamping said stack of paper to engage and to hold the stack of paper in place prior to the drill engaging the paper.
22. A method, according to any one of claims 18 to 21, including the steps of: retaining paper swarf in the flute of said drill; and depositing retained paper swarf, on completion of perforation of the paper, into a waste receptacle.
23. A method, according to any one of claims 18 to 22, including the step of employing, as said means to cause the platform and the stack of one or more sheets of paper to approach one another, a rack in conjunction with a rack gear.
24. A method, according to any one of claims 18 to 22, including the step of employing, as said means to cause the platform and the stack of one or more sheets of paper to approach one another, a lead screw mechanism.
25. A method, according to any one of claims 18 to 22, including the steps of: employing, as said means for causing said platform and said stack of one or more sheets of paper to move towards each other, a rotatable cam to be pressed against a static upper member to cause said platform to move away from a start position; employing means to rotate said cam; and employing spring restorations means for applying a restoring force to return said platform to said start position after the paper has been perforated.
26. A method, according to claim 25, including providing a common motor, coupled to rotate said drill and said cam
27. An method, according to any one of claims 18 to 22, including the steps of including in said means for causing said platform and said stack of one or more sheets of paper to move towards each other; first means to alter the configuration of a

<Desc/Clms Page number 21>

platform-supporting frame to cause said platform and said stack of one or more sheets of paper to move from a start position towards each other; and second means to restore the configuration of said platform-supporting frame to cause said platform and said stack of one or more sheets of paper to return to said start position.
28. A method, according to claim 27, including the steps of: employing, as said first means, a screw, and means to rotate said screw to reduce the linear distance between two members of said frame ; and employing, as said second means, said screw, and means to counter rotate said screw to restore the linear distance between said two members of said frame.
29. A method, according to any one of claims 18 to 28, including the step of causing said means for rotating said drill and said means to cause the platform and the stack of one or more sheets of paper to approach one another to co-operate to perform a single drilling cycle, starting from an initial position, moving to perforate the paper, and then returning to said initial position.
30. A method, according to claim 29, wherein the extremity of movement of said means to cause said platform and the stack of one or more sheets of paper to approach one another is controllable by a limit switch.
31. A method, according to claim 29 or claim 30, including controlling movement and direction by one or more cross over switches.
32. A method, according to any one of claims 18 to 31, wherein said drill comprises a single flute auger tipped drill.
33. A method, according to any one of claims 18 to 32, including the steps of: performing a cycle of operation to perforate paper; and initiating said cycle in response to a single and brief operation of a push button.

<Desc/Clms Page number 22>
34. A method, according to any one of claims 18 to 33, wherein said drill is one of a plurality of spaced drills.