There are many known devices for binding the papers forming a document together. Many of these have problems in that they are only temporary, such as paper clips and bull-dog clips, which are prone to inadvertent removal and the loss of document sheets or document mis-ordering.

More permanent mechanism are often unsightly, do not allow removal under any circumstances and/or are difficult to insert. Indeed, many require complex manual fasteners and cannot be used as part of an automated process.

Previous devices for forming holes in a number of sheets of paper have suffered from not being able to easily and cleanly form holes through documents having a large number of pages. This failure usually requires an operator to remove the document from the hole forming device and subsequently separate it into smaller sections, realign and then reinsert it into the hole punching apparatus. This process is time consuming and may have to be repeated, if the sections are still too thick.

It is an object of the present invention to provide a simple and quick method for binding a number of sheets of paper together, to provide simple and reliable bindings which will prevent the document from easily being separated and to provide a simple and quick method for forming a number of holes in a document.

According to an first aspect of the present invention there is provided a paper binding for retaining a number of pieces of paper, the binding comprising a spine having a plurality of protrusions arranged along its length, the protrusions being arranged so that they can be bent, in use, to pass through holes formed in the paper to be bound

and to engage with a clip formed on the surface on the spine.

Each of the clips may comprise a hook, which engages, in use, with one or more teeth formed on each protrusion.

Alternatively, each clip may comprise two arms, between which, a corresponding protrusion is inserted, together with a retaining rib formed between the arms, the rib engaging, in use, with a recess in the corresponding protrusion. In this case, each protrusion may have a plurality of recesses, so that the extent of insertion of the protrusion into the clip can be controlled and can be varied dependant upon the number of sheets of paper to be retained by the binding.

The binding may be formed from card, metal, or a plastics material. The binding may be formed by injection moulding. Preferably the material from which the binding is formed is resilient, the resilience generating an engaging force which engages the projections into secure engagements with their corresponding clips.

According to a second aspect of the present invention, there is provided a paper binding apparatus comprising: a first curved die; a second curved die, the first and second dies being moveable relative to each other; and a support for supporting, in use, a paper binding for binding a number of sheets of paper; wherein the curvature of the first die is such that, in use, it receives and directs protrusions on the paper binding through holes in a number of sheets of paper, the holes in the paper being located between the first and second dies, when the dies move toward one another; and the curvature of the second die is arranged, in use, to direct the protrusions from the first die towards retaining means on the paper binding during further movement of the dies.

The support may be arranged, in use, to prevent buckling of the protrusions.

According to a third aspect of the present invention, a hole punching apparatus comprises a paper receiving section having, on at least one side, a number of movable steps for, in use, separating the paper into sections, each step having a number of holes formed therethrough, step moving means for, in use, moving the steps in a specific configuration to alter the alignment of the paper sections, and means for, in use, punching a hole through at least one section of paper.

Preferably the step moving means comprises a rotatable shaft having a series of cams mounted thereon, each cam corresponding to a removable step and being fixed in one of at least two predetermined orientations.

The movable steps may have interlocking portions to prevent paper from becoming trapped from adjacent steps.

Preferably the movable steps separate the paper into sections having a maximum of 30 sheets.

Separating the document into sections reduces the force required to punch a hole through a thick document as it can be carried out in stages, i. e. by punching section by section may require only a maximum of 30 sheets (for example) to be sheared in one go.

According to a fourth aspect of the present invention, a hole punching mechanism for forming holes in paper comprises a hollow pin mounted at one end of a lead screw, the lead screw being fixed at its other end to prevent rotation thereof, and a motor for, in use, driving a primary gear which is mounted in driving engagement with the lead screw to force the hollow pin through paper.

The hollow pin may be provided with a screw thread which engages with a stationary nut, and, as the hollow pin rotates, the pin is forced to move linearly.

Alternatively the hollow pin may be rotatably mounted on the lead screw and may have a secondary gear mounted

thereon, the secondary gear being in driving engagement with the main gear via a mating gear.

The hole punching mechanism may further comprise a guide rail on which the lead screw is movably mounted so that holes can be formed in more than one location in the paper sections.

According to a fifth aspect of the present invention, a hole punching mechanism for forming holes in paper comprises a motor for driving, in use, at least two gears mounted on respective lead screws, a guide rail on which the lead screws are slidably mounted at one end, support for supporting the other end of the lead screws, a link bar, movably mounted on the lead screws, and at least one hollow pin mounted on the link bar for forming holes in paper, wherein driving of the motor causes the hollow pins to be moved.

This arrangement allows many holes to be punched simultaneously.

According to a sixth aspect of the present invention, a method of forming holes through a number of sheets of paper comprises the steps of separating the sheets of paper into sections; altering the alignment of the sections so that some sections extend beyond the others and can have at least one hole formed therethough; forming at least one hole through the sections which extend beyond the others; and repeating the altering the alignment and hole formation steps until all the sections have had at least one hole formed therethrough.

According to a seventy aspect of the present invention, a method of forming at least one hole through a number of sheets of paper comprises the steps of separating the paper into sections; forming a gap between each section; and urging at least one pin through at least one bore in a die to form at least one hole through each section.

Between 5 and 15, preferably 10, pins may be used to form holes through each section.

Preferably the sections of paper each comprise a maximum of 30 sheets of paper.

The paper sections may be vibrated and/or fanned to ensure correct alignment of the paper prior to hole formation.

According to eighth aspect of the present invention, a method of binding a number of sheets of paper comprises the steps of: using at least one pin to punch at least one hole through the paper; repeating the hole punching until the requisite number of holes are formed; and placing a binding through the holes to secure the paper.

The pin may be hollow and may be rotated during the formation of a hole and preferably is rotated at between 120 and 600 rpm.

The use of a hollow pin reduces the force required for punching holes through a document and also reduces the amount of swarf and paper dust which would be produced by drilling for example. Paper dust and swarf can clog mechanical components within the hole punching apparatus and, additionally, swarf and dust attract moisture which can lead to rusting and/or degradation in materials. The presence of moisture means that electronic components would have to be sealed to prevent them being effected. The use of a hollow pin allows the majority of the swarf and dust to collect inside the pin and leads to easy disposal of the waste.

Rotating the pin reduces the required force to punch through sections of paper as the rotation ensures that the paper is cut rather than sheared. Limiting the speed of rotation of the pin means that the process remains quiet.

Punching through all the paper in a document ensures no mis-alignment of the holes through the document and, accordingly, that there is no need to realign the document prior to binding.

According to a ninth aspect of the present invention, a hole punching die comprises a number of separating fins for separating a number of sheets of paper into sections,

and a bore to which, in use, a pin can be forced to form a hole through each section of paper. The use of a die to separate the paper into sections allows the document to be punched in one hit by a circular pin. This is possible as the punch will treat the document as numerous individual sections instead of one thick section. The document may be punched numerous times by one or more pins or merely once by a larger number, e. g. 10, pins to form all of the requisite holes.

According to an tenth aspect of the present invention, a paper binding for retaining a number of pieces of paper comprises at least one loop, the at least one loop having a first and a second section, each section having cooperating end portions so that, in use, the first and second sections can be fitted together, and a connecting spine portion for engagement, in use, with the first and second sections to fasten them securely together.

The connecting portion may be corrugated or score cut.

This ensures that the document can easily be opened flat and provides a professional appearance to the document as well as being aesthetically different. The manufacture of such a corrugated section is simple as the spine may be extruded. It may be possible to print information on the corrugated spine. The corrugations or score cuts permit the required width to be cut from a bulk roll supply with minimum effort in the binding machine. There is therefore no need to store and retrieve individually sized spines inside the machine and, accordingly, every spine can be tailored to match the thickness of the document being bound.

According to an eleventh aspect of the present invention, a paper binding for retaining a number of pieces of paper comprises a spine having a number of holes therethrough, protrusions extending from the spine, one protrusion substantially opposite each hole such that, in use, the protrusions can be looped into the corresponding holes to form loops, and fastening means for, in use,

securely fastening the protrusions in the corresponding holes.

Preferably the loop is either circular or D-shaped.

The vertical section on the D-shape may form a flat spine on which text can be printed.

The spine may be corrugated or score cut.

According to a twelfth aspect of the present invention a paper binding for retaining a number of pieces of paper comprises a flexible spine having, at each side, longitudinally spaced cooperating pairs of protrusions such that, in use, one protrusion of the pair of protrusions is slidable located in the other protrusion of the pair of protrusions.

The spine of this paper binding may be corrugated or score cut.

Examples of the present invention will now be described with reference to the accompanying drawings, in which: Figure 1 is a side view of a hole punching mechanism, according to the first aspect of the present invention; Figure 2 is a side view of a second hole punching mechanism; Figure 3 is a side view of a third hole punching mechanism; Figure 4 is a plan view of the hole punching mechanism shown in Figure 3; Figure 5 is a perspective view of a number of movable steps; Figure 6 is a perspective view of a rotatable cam shaft; Figure 7 shows three positions of the cam shaft; Figure 8 shows the vibration of paper sections; Figure 9 shows the interlocking portions between movable steps; Figure 10 shows a side view of a hole punching die; Figure 11 shows a circular and a D-shaped paper binding;

Figures 12 and 13 show the use of a corrugated binder; Figure 14 shows a perspective view of another paper binder; Figure 15 shows a cross sectional view through a document bound with the paper binder of Figure 14; Figure 16 and 17 show cross sectional views of a document bound using another paper binder; Figure 18 shows a perspective view of a document bound using the paper binder of Figures 16 and 17; Figure 19 is a schematic side view of a binding according to another aspect of the invention in a closed configuration; Figures 20A and 20B are side and forward views of a first example of the binder of Figure 19; Figures 21A, 21B and 21C are side and plan views of a second example of the binder of Figure 19 with projections in various stages of engagement with corresponding clips; Figure 22 is a schematic view of an alternative projection arrangement that may be employed with the example of figures 21A to 21C.

Figure 23 shows a perspective view of another example of a paper binder; Figure 24 shows a different perspective view of the paper binder of Figure 23; and Figures 25A to 25C show schematic views of a paper binding apparatus at various stages during its operation.

Referring to the drawings, Figure 1 shows a hole punching mechanism 10 having a motor 11, a driving gear 12 and a main gear 13. The main gear is mounted coaxially around a lead screw 14 which is fixed at one end 15 and at its opposite end is provided with a hollow pin 16. The fixed end 15 of the lead screw 14 ensures that the lead screw does not rotate and yet permits the lead screw to slide freely in a linear direction. The main gear 13 is held in position and allowed to rotate.

Figure 2 shows another hole punching mechanism 20, similar to that of Fig. 1, and which permits the hollow pin

16 to rotate as it is moved in a linear direction. The hollow pin 16 is mounted in a bearing 17 on the end of the lead screw and there is a secondary gear 18 mounted coaxial with and around the bearing 17 which is in driving engagement with a mating gear 19 which, in turn, is in driving engagement with the main gear. Thus rotation of the main gear 13 initiates linear movement of the lead screw 14 and hence of the hollow pin 16 and also drives the mating gear 19 which, in turn, drives the secondary gear 18 to rotate the hollow pin 16. The mating gear 19 is sufficiently long to ensure that the secondary gear 18 will remain in mesh with the mating gear 19 throughout operation.

Figures 3 and 4 show a hole punching mechanism 30 having multiple lead screws 14 and multiple pins 16. The lead screws are mounted at one end to a guide rail 21 which permits the mechanism to move across the face of a document to allow repeated hole punching. Gears 22 are mounted on the lead screws adjacent to the guide rail 21 for engagement with a driving gear 12, driven by a motor 11.

The opposite ends of the lead screws are attached to lead screw supports. Mounted on the lead screw is link bar 24 and extending from the link bar are the pins 16. As the motor 11 drives the driving gear 12, the lead screws 14 are forced to rotate. This drives the link bar 24 to urge the pins 16 through paper sections.

The movable steps 25 shown in Figure 5 are provided with corresponding holes 26 which extend through all the movable steps 25. The hole punching mechanism uses these holes as a die for punching holes in the paper sections 27.

There may be up to 10, preferably 5 or 6, movable steps 26 and they can be moved by approximately 20 mm. The steps 26 are about 3 mm wide.

The movable steps 26 are moved using a cam shaft 28 shown in Figure 6. Alternating cams 29 are shown in two different orientations and these orientations provide the three possible arrangements shown in Figures 7A, 7B and 7C.

Figures 7A and 7B show alternating cams 29 in a raised position for moving the steps 25 and hence separating the paper sections. The holes through the paper sections are formed when the cam shaft is in each of these positions.

Figure 7C shows all the cams 29 in a neutral position, either prior to hole formation or after hole formation has been carried out.

Figure 8 shows the paper sections 27 being vibrated and fanned in order to ensure correct alignment of all sheets of paper.

Figure 9 shows one possible arrangement of interlocking portions on the movable steps. Adjacent steps 25 are provided with interlocking tongue 31 and groove 32 portions. This prevents pieces of paper from being inadvertently trapped between each movable step.

Figure 10 shows a hole punching die 33 having separating fins 34 and a bore 35 extending there through.

The separating fins 34 ensure that the document is separated into a number of sections. A gap, corresponding to the separating fins, is created between each section and then the hole punching mechanism punches a hole through all of the sections in one hit. The hole punching device can then treat the document as numerous individual sections.

Figures 11A and 11B show two paper binders 36 having first 37 and second 38 sections. Each section has cooperating end portions 39 which form a snap fit to create a loop. An engagement portion 40 can then be connected between the first 37 and second 38 sections to ensure a secure fastening and a professional appearance. Between 2 and 15 loops can be used on each document. It is possible to print text on the connecting portion to provide information.

Two examples of a corrugated binder 41 attached to an open and closed document are shown in Figures 12 and 13 respectively. The corrugations are on the inside of the binder in Figure 12 and on the outside of the binder in

Figure 13. This binder can be used with any of the paper loop binders.

The binder 42 shown in Figure 14 has a spine 43 having a number of ribs 44 extending from one side thereof. The ribs 44 can be looped over following the paths shown and inserted through the holes 45 in the spine. The circumference of the binding can be altered depending upon the size of the document and the ribs are then bonded to the spine by means of either heat, ultrasound, and adhesive or a combination thereof. Alternatively a mechanical binding, similar to that used in cable ties, could be used.

A combination of chemical and mechanical bonding may be used. Figure 15 shows a cross sectional view through a document having the binding described above.

Figures 16,17 show another binding 45 having a flexible spine 46 and pairs of interconnecting ribs 47,48.

In the open position shown in Figure 17, the rib 48 is only partially located in the rib 47. In the closed position shown in Figure 16, rib 48 is fully located in rib 47. A perspective view of a document bound using this type of binder is shown in Figure 18.

Referring to Figure 19, a binding 1 according to the invention has projections 2 which pass through hole 3 in sheets of paper 4. The projections 2 engage with clip 5 formed in the spine 6 of the binding 1 and are retained in position. The spine conceals the clip 6 and provides an overall aesthetically pleasing binding, whilst still providing a rigid binding regardless of the number of sheets that are retained.

Figure 20 shows a first example binding 1, in which the clip 6 comprises hook 7, which receives the end of projections 2 which are concealed, in use, by the spine.

In this example, the clips 6 each comprise two separate hooks, which each engage with a respective finger line formed on the end of a respective projection 2.

Figures 21A to 21C show an alternative example, in which each clip has two receiving arms 10 into which the

projection 2 is inserted, with the projection 2 having a narrow finger at its end. In use, the projections 2 pass into the arms 10 of the clip and engage with a rib 11 formed in the clip, with the projections being retained in position by engagement of the rib 11 with a recess 12 formed in each projection.

Figure 22 shows an example projection that may be employed with the example of figures 21A to 21C, in which plural recesses 12 are provided on each projection 2, together with plural narrow portions. This enables a single spine size to be adapted for use with a wide range of document thicknesses. During the binding process, the projections are trimmed to the optimum length for the document being bound, by cutting off a number of these repeated features. Provided that at least one feature remains, the trimmed projections will still engage with the clip arms 10 and the ribs 11 formed in the spine.

Figure 23 shows an example of another alternative paper binding 113 in which projection retaining means is provided by retaining loops 114 having tabs 115 which engage with one of a number of ribs 116 on the surface of a protrusion 117. Figure 24 shows an alternative perspective view of the paper binding shown in Figure 23.

The ribs 116 are flushed with the underside of the protrusion to prevent them from snagging on the paper during and after the binding process. The plurality of ribs 116 enables different numbers of sheets of paper to be bound using a single type of binder, any excess length of protrusion can be trimmed during the bdingin process.

Figures 25 show a schematic view of an apparatus for binding paper using paper binders as shown in Figures 14, 15 and 19 to 24. A paper binder 118 is supported on a support 119. A first curved die 120 is moved towards a second curved die 121 in the direction of the arrows in Figures 25B and 25C. The first curved die engages the tip of a protrusion 122 of the paper binder, the tip being guided by the curved part of the die and directed towards

a set of holes formed in a number of sheets of paper 123 to be bound. On further movement of the first die the tip of the protrusion passes through these holes and engages with the curved part of the second die. The tip of the protrusion is then directed, by the second die towards, and into, retaining means 124 on the paper binder.