GB2055665A - Device for the punching and reinforcing of holes in paper - Google Patents

Abstract

A device for punching holes in a paper sheet and applying reinforcement around the punched holes, in one operation, comprises a body (20) having at least one punching pin (26) depressable in a conventional manner by a handle against the action of a spring (32), a channel (45), open at one side, for insertion of a sheet of paper beneath each punching pin, a first die aperture (51), below said open channel and above said channel a closed channel (42) for guiding a tape of self-adhesive material, each punch having (a) an end portion (40) of a size to punch the desired size of hole in the paper in cooperation with said first die aperture, and (b) a larger portion surrounding the end portion and set thereabove, which cooperates with a second die aperture (44) beneath the closed channel so as to punch a reinforcement from tape in said closed channel and then to press the cut tape onto paper. <IMAGE>

Description

SPECIFICATION Device for the punching and reinforcing of holes in paper The invention relates to a device for punching holes in paper and also applying reinforcement around the holes.

Punches for making holes in paper (or similar sheet material) are well known. It is also known to separately apply gummed or selfadhesive circular reinforcements around punched holes. The present invention provides a device whereby these two operations can be conveniently and speedily combined.

In the invention, a tape of self-adhesive material is fed beneath the punching mechanism. Such tape is commercially available.

The invention will be described by reference to the preferred embodiment shown in the accompanying drawings; wherein: Figure 1 is a front view of an entire twohole punch, equipped with a reel of punching reinforcements; Figure 2 is a side view, from direction X of Fig. 1, of the device; Figure 3 shows in perspective part of one end of the punch operating handle and the post on which it is mounted; Figure 4 is a vertical section through a punch, on line Z-Z of Fig. 1; Figure 5 is a vertical section on line Y-Y of Fig. 1, showing the tape channel; Figure 6 is a perspective view of one form of lower surface of a channel as shown in Fig.

5; Figures 7 and 8 are fragmentary views of the lower part of the punch as shown in Fig.

4, during two steps in the punching operation; Figure 9 shows a self-adhesive tape for use in the device; Figures 10 and ii are respectively a perspective view and side view of a tape indexing mechanism; and Figures 12 and 13 are end views of the arrestor assembly of Fig. 10 (without side plates), respectively in rest position and operating position.

Referring to Figs. 1 and 2, the device comprises generally a punch 2, a feed mechanism 4 and an indexing mechanism 6. The punch has an operating handle 8 and a body 10. The feed mechanism includes a support 1 2 for a reel 1 4 of pressure-sensitive plastic or paper reinforcing tape, and a guide roller 1 6 for tape 1 8 from the roll, which tape is shown in broken line in Fig. 1 passing beneath the punch mechanism.

Figs. 3 and 4 show how the punch mechanism is constructed. Each end of the handle 8 is attached to a post 20 of the body by pivot pins 22 which fit into hole 24. Within each post is a cylindrical punch 26 having at its upper end a cross-pin 28 which is movable in vertical slots 30 in the post 20 and fits into slots 31 in the handle. A compression spring 32 mounted around the punch bears against a washer 34 which fits under the cross-pin 28 and thus the handle and punch are normally urged upward until lugs 36 on each end of the handle meet stop pins 38 on the posts.

Any other suitable similar structure can be used for the punch mechanism, and the number of punches can be varied from the two punches shown.

Each punch 26 has a diameter D1 which is the same as that of the reinforcement to be applied around the punch hole, except for a smaller lowermost piece 40 which is of a smaller diameter D2 which is that of the hole to be punched in the paper.

Beneath the punch there is (see Figs. 4, 7 and 8) a channel 42 for the tape 1 8 beneath which is a blanking die 43 having an aperture 44 of size D1, beneath which is a slot 45 which allows entry of paper to be punched to a depth determined by the position of a backstrip 46 and beneath this is a piercing die 48 which is recessed into a base plate 50 and has an aperture 51 of diameter D2.

Between the punching stations the channel 42 is open above, as seen in Fig. 5; the lower wall of the channel is formed by a plate 52 (replaced by the blanking dies 43 at the punching stations). The tape 1 8 travels through the channel with its pressure-sensitive surface downwards; so as to minimise any adhesion of this tape to the lower face of the channel, this face of plate 52 may be coated with an anti-stick material such as polytetrafluoroethylene, or may have ridges 54 to give a reduced contact area, as shown in Fig. 6.

In operation, by pressing the handle 2 so as to depress the cross-pins 28, a sheet of paper or similar sheet material inserted in the slot 45 is punched in conventional manner by the punches 26, and the depression of the punch also causes a circular piece of reinforcement to be cut out from the tape 1 8 and adhered around the punched hole. This will be described with reference to Figs. 7 and 8. A sheet of paper 54 is inserted in slot 45.The punch 26 is first depressed so as to cut a circular piece 56 of reinforcement of diameter D1 from the tape 18, by means of the larger diameter portion of the punch cooperating with the inner edge of the aperture 44 of upper die 43. (Fig. 7) The punch is further depressed, and carries the cut piece of tape (pressure-sensitive side downwards) onto the paper, and a punch hole of diameter D2 is then cut in both this piece of tape and the paper by means of the smaller size portion 40 of the punch and the aperture 51 in the lower die.As the punch reaches the bottom of its travel (Fig. 8) it firmly presses the reinforcing piece of tape onto the paper whilst the punched material 58 falls out of aperture 51 of the lower die 48 in the underside of the base plate 50; if the punched material sticks to the end 40 of the punch, it will be stripped therefrom at the die 43 as handle 2 is released and the spring 32 causes the punch 26 to move upwards.

After each punching operation the tape 1 8 must be moved through the channel 42 so that a fresh portion is available for the next punching operation. A roller mechanism (not shown) geared to the punch handle 2 might be provided to thus advance the tape; otherwise the tape must be advanced by manually pulling it. Where, as shown in Fig. 1, two or more punches are present in the same device, it is necessary to provide means to ensure that an already punched portion of tape, e.g. as shown at A in Fig. 9, is not positioned beneath the other punch at B. Register marks on the side of the open channel 42 between the punches can be provided for visual guidance in positioning previously punched holes in the tape as it is pulled, or else an indexing mechanism can be used. This mechanism 6 is fixed rigidly to the punch body in the position seen in Fig. 1.

Referring to Figs. 10 to 1 3, in two sideplates 62, 64 are supported three rollers, namely a guide roller 66, an indexing roller 68 (which are each contacted by the tape 1 8 as shown in Fig. 11) and an arrester shaft 70.

The guide roller 66 serves to keep the tape in proper alignment, together with roller 1 6 (Fig. 1), during its passage through the channel 42.

The pressure-sensitive side of the punched tape 1 8 passes over the indexing roller 68.

The surface of this roller is of such a nature as to limit the adhesion of the tape to that which is necessary to rotate the roller, and the surface can be of a material, such as silicone rubber, which has little affinity for pressuresensitive adhesive, or a surface pattern (e.g.

on a metal roller) such as diamond-knurling, which gives a good grip when a tangential pull is applied to the tape but presents a small surface area to the tape. To each end of this roller 68 is rigidly fixed a radial arm 72, 74, which arms are angularly offset from each other by about 120 , as seen in Figs. 12 and 13, each of which arms has a pin 76, 78 projecting towards its respective side plate 62, 64 and with the axis of each pin parallel to that of the rollers 66, 68, 70.

To the respective ends of the arrester shaft 70 are rigidly fixed (a) a lever 80 which cooperates with pin 76, the travel of lever 80 being limited by a stop pin 82, mounted on side plate 64, which is covered with a resilient layer 84, e.g. of rubber, and (b) an arrester plate 96 in the form of a disc flattened at one portion (which cooperates with pin 76); together this mechanism serves to arrest rotation of roller 68, as will now be described with reference to Figs. 1 2 and 13.

When at rest, the arrester assembly adopts the position shown in Fig. 1 2 due to its eccentric centre of gravity; this is so located as to induce a low initial acceleration of the assembly from its operating position shown in Fig. 1 3. When the tape is pulled over the indexing roller 68, causing it to rotate anticlockwise in the direction of arrow X, the pin 78 in arm 74 contacts lever 80, so turning the shaft 70 in the opposite (clockwise) direction until it is prevented from turning further by the lever 80 hitting stop 82.Pin 78 continues in its path pressing lever 80 into the resilient covering (Fig. 14) until the pin clears the end of the lever, at which point the resilient covering assumes its former shape thus moving lever 80 back into the path of pin 78 and so prevents any reverse motion of the indexing roller 68 (which could otherwise occur due to the tension in the tape 18 when the force is removed, which could cause the pin 72 to move back over lever 80 before the arrester assembly can begin to move back to its rest position under gravitational force).

There is a position of arrester shaft 70 wherein the pin 78 will have cleared lever 80 before the pin 76 on arm 72 contacts arrester plate 86. At this position the arrester assembly is free to return to its rest position. However, due to the relative speeds of the indexing roller 68 (due to the force applied by pulling the tape) and the arrester assembly (starting from zero under gravitational force), contact occurs before the arrester plate 86 can clear the path of the pin 76 and the indexing roller 68 and tape 1 8 are brought to a halt. As soon as the pull on the tape is removed, the arrester assembly is free to return to its rest position as in Fig. 12.Since the exact point of contact on the periphery of the arrester plate 86 of pin 78 will depend upon variable factors, such as the relative speeds of indexing roller 68 and arrester plate 86, the part of plate 86 which is available for contact is at a fixed distance from the axis of the arrester shaft 70, to maintain the pitch of the punched holes. For convenience of manufacture, therefore, plate 86 is circular about the centre of the shaft but is cut away to allow free passage for pin 78 when the assembly is in the rest position.

At the position where pin 78 is in contact with arrester plate 86, pin 76 is clear of lever 80 by a few degrees of rotation of indexing roller 68. This clearance, translated into circumferential movement of the indexing roller, represents the tolerance of pitch between the punched holes in the tape.

By making the circumference of the indexing roller 68 equal to the required pitch between the holes 1 punched at the same time, the tape can be moved by the desired amount at each operation. In Fig. 9, the punches A, B are spaced 22 times the pitch of the holes A, A1, A2, A3. If no reinforcements are required during punching, the tape is not pulled and so is left in the position where it was last punched.

The device of the invention thus allow punched reinforcements to be conveniently and efficiently applied simultaneously with the punching of holes, and the reinforcing material is simply a strip of pressure-sensitive tape; preformed reinforcements are thus not needed.

The significant part of the described device as shown in Figs. 1 to 8 is that there are means for guiding self-adhesive tape below the punches, each punch has a small diameter end portion of conventional size to punch the paper and thereabove a larger diameter portion to punch the reinforcement from the tape, and appropriate size dies therearound to cooperate with the punch and to provide a surface onto which a cut piece of tape can be firmly pressed by the punch onto the paper.

Claims (4)

1. A device for punching holes in a paper sheet and also applying reinforcement around the punched holes, which comprises a body having at least one punching pin depressable by a handle against the action of a spring, a channel, open at one side, for insertion of a sheet of paper beneath each punching pin, a first die aperture below said open channel and above said channel a closed channel for guiding a tape of self-adhesive material, each punch having (a) an end portion of a size to punch the desired size of hole in the paper in cooperation with said first die aperture, and (b) a larger portion surrounding the end portion and set thereabove, which cooperates with a second die aperture beneath the closed channel so as to punch a reinforcement from tape in said closed channel and then to press the cut tape onto the paper.

2. A device as claimed in Claim 1, which includes means for advancing a tape along the closed channel after each operation of the punch.

3. A device as claimed in Claim 2, which includes two or more punch pins and means for indexing the advance of the tape so that an already punched portion of the tape is not subsequently positioned beneath a punch pin.

4. A device as claimed in Claim 1, substantially as hereinbefore described with reference to Figs. 1 to 9 or Figs. 1 to 1 3 of the accompanying drawings.