PRESSING DEVICE FOR A BINDING MACHINE

Abstract: A pressing device comprises a housing (6) comprising a slide plate (8) mounted for rectilinear movement at an angle at about 45 DEG to the horizontal. The rear end of the slide plate (8) is provided with spaced flanges (20, 21) between which at spaced positions widthwise of the slide plate two fixed nuts (22) are provided. Extending in each of the fixed nuts (22) is an adjustment screw (24a &cir& _, 24b &cir& _), each of said screws (24) being secured at its forward end to one end region of a presser plate (26). Thus, by rotation of the adjusting screws, the position of the presser plate (26) is adjusted relative to the flange (20). Mounted above the slide plate (8) at a position below the presser plate (26) and facing the presser plate (26) is a base plate (40), fixed in relation to the machine housing, the base plate and slide plate together providing the support for the binding element. Extending around the two adjustment screws (24a &cir& _, 24b &cir& _) is a flexible belt (36), the belt (36) being moved by rotation of an adjustment wheel (30), to ensure equal and simultaneous adjustment movement of the two adjustment screws. In this manner the device may be utilised with binding elements of a larger variety of sizes.

Description: Title: "Pressing device for a binding machine" Description of Invention This invention is concerned with improvements relating to binding machines; and in particular to a pressing device for a binding machine. A known method of binding perforated sheets uses binding elements which are afforded by lengths of wire bent so as to form curved prongs on which the sheets may be impaled. The elements are provided, at the time of the impaling operation generally, in the form of a tube having a longitudinal slot in the wall, and the final stage in the binding process involves closing the slot by bringing the closed ends of the prongs into their open ends. Such binding elements (hereinafter referred to as being of the kind specified) are provided in a variety of sizes, and in a variety of pitches, enabling an appropriate element to be selected for a particular binding operation, and it is of course desirable that a binding machine (conventionally comprising a punch, to punch a row of holes along one edge of a stack of sheets, and a pressing device, to deform the binding element to a closed condition) be capable of being used with a variety of such binding elements. According to this invention there is provided a pressing device for clamping a binding element of the kind specified around the spine of a stack of sheets, comprising a support, on against which a binding element may be placed, and a presser member movable to effect closing of the binding element, characterised by the provision of an adjustment mechanism comprising two screw- threaded devices operable to move the presser member to accommodate binding elements of different sizes, means being provided to ensure simultaneous and equal adjustment of the two screw-threaded devices. In this manner, substantially rectilinear approach and separation between the presser member and the support may be ensured. Preferably the support on which the binding element is placed is provided in part at least by a relatively fixed base, conveniently in the form of a plate, against which a binding element may be placed. Preferably the device comprises operating means to move the presser member towards the base plate in a pressing operation, and away therefrom, the adjustment mechanism being interposed between the operating means and the presser member. The operating means may comprise a slide member upon which the adjustment mechanism is mounted, the presser member being carried by the slide member in the operation of the device. Preferably the two screw-threaded devices are carried by the slide member and in turn support the presser member. Thus preferably the means to ensure simultaneous adjustment of the two screw threaded devices is also carried by the slide member. Preferably the slide member also affords part of the support for the binding element, and is conveniently in the form of a plate, advantageously extending at right angles to the base, and preferably inclined to the horizontal so that the binding element is retained in a corner defined by two support surfaces, one afforded by the base plate and the other by the slide plate. Preferably the two screw-threaded devices are connected together by a flexible endless element, such as a belt drive, but if desired a worm and worm wheel may be utilised. Advantageously the flexible elongate element is capable of being moved in an adjustment operation, by rotation of a wheel of relatively large diameter, conveniently a knurled wheel, the flexible elongate element engaging the two screw-threaded devices to cause simultaneous movement of opposite end regions of the presser member. Conveniently the adjusting wheel is mounted co-axially with one of the screw-threaded devices, but if desired the wheel may be mounted between the two devices. There will now be given a detailed description, to be read with reference to the accompanying drawings, of a clamping device which is the preferred embodiment of the invention, having been selected for the purposes of illustrating the invention by way of example. In the accompanying drawings:- FIGURE 1 is a schematic vertical sectional view of part of the machine which is the preferred embodiment of the invention; FIGURE 2 is a plan view of part of the machine, taken in the direction of the arrow A of Figure 1; and FIGURE 3 is a perspective view showing a binding element of the kind used in the use of the illustrative device. The device which is the preferred embodiment of the invention is part of a binding machine, and reference may be made to the specification of our co- pending International Application No.GB92/02106, for the construction and operation of other parts of the machine not described herein. The machine comprises a housing 6 comprising a slide member afforded by a plate 8 capable of rectilinear movement at an angle of about 45°, i.e. in the direction of the arrows B-B of Figure 1, and spaced arms 10, pivotally mounted on a common axis, engageable in apertures 12 of the slide plate 8, to move the slide plate in the direction of said arrow B-B. The arms 10 are each provided with a slot 14, within which a pin 16 engages, the pin being provided by a bell crank lever rotatable by a drive shaft 18. Thus, on rotation of the drive shaft 18, the slide plate 8 is moved from the position shown in full lines in Figure 1 to the position shown in dotted lines in Figure 1. The rear end of the slide plate 8 is provided with spaced flanges 20, 21, between which at spaced positions widthwise of the slide plate two fixed nuts 22 are provided. Extending in each of the fixed nuts 22 is an adjustment screw 24a, 24b. respectively, each of said screws 24 being secured at its forward end to one end region of a presser plate 26 (see also Figure 2). Thus, by rotation of the adjusting screws, the position of the clamping plate 26 is adjusted relative to the flange 20. Mounted above the slide plate 8 at a position below the presser plate 26, and facing the presser plate 26, is a base plate 40, said base pate being fixed in relation to the housing 6. The base plate 40 and slide plate 8 together afford a support for a binding element, being provided by a corner between two ' mutually perpendicular surfaces, one being afforded by the base plate 40, the other by the slide plate 8. One of the adjustment screws 24a . has fixedly mounted thereon a knurled adjustment wheel 30, more readily to positionally adjust the screw 24a, and extending around a boss portion 32 fixed to the screw 24b . is a flexible belt 36, said belt 36 extending around also a similar fixed boss 32 on the other adjustment screw 24. In this manner when the adjustment screw 24a is adjusted by rotation of the wheel 30, a commensurate adjustment of the other adjustment screw 24b_is produced. In this manner, once the presser plate 26 has been initially adjusted so that it is parallel with the base plate 40, conveniently effected by a temporary removal of the belt 36 whilst adjustment of one of the screws 24 is effected, it is ensured that the presser plate 26 will be retained parallel to the base plate 40, notwithstanding positional adjustment of the presser plate 26. In use, a binding element 50 (shown in perspective in Figure 3) is passed through the apertures 52 of a stack S of sheet material, in conventional manner, and the drive spindle 18 is rotated to cause the presser plate 26 to move relative to the base plate 40, compressing the binding element 50 around the marginal edge of the stack S, to effect a binding operation in a conventional manner, with the prongs of the binding element passing into apertures between adjacent prongs on opposite sides of the tube. When it is desired to utilise the machine with a smaller size of binding element (such as one of the size shown in dotted lines in Figure 1), by rotation of the wheel 30 the presser plate 26 may be moved towards the base pate 40, into a position such that on completion of driving movement of the spindle 18, the presser plate 26 has effected a sufficient movement to cause desired closure of the binding element 50. The features disclosed in the foregoing description, or the accompanying drawings, expressed in their specific forms or in the terms or means for performing the desired function, or a method or process for attaining the disclosed result, may, separately or in any combination of such features, be utilised for realising the invention in diverse forms thereof.

Claims: CLAIMS 1. A pressing device for clamping a binding element (50) of the kind specified around the spine of a stack(s) of sheets, the device comprising a support (8, 40) on which a binding element may be placed, and a presser member (26) movable to effect closing of the binding element, characterised by the provision of an adjustment mechanism provided by two screw-threaded devices (24a, 24b) operable to move the presser member (26) to accommodate binding elements of different sizes, means (30, 36) being provided to ensure simultaneous and equal adjustment of the two screw-threaded devices. 2. A pressing device according to Claim 1 wherein the support is provided in part at least by a relatively fixed base (40) against which a binding element may be placed. 3. A pressing device according to Claims 1 and 2 comprising operating means (10, 12) to move the presser member (26) towards the base plate (40) in a pressing operation, and away therefrom, the adjustment mechanism being interposed between the operating means (10, 12) and the presser member (26). 4. A pressing device according to Claim 3 wherein the operating means comprises a slide member (8) upon which the adjustment mechanism (30, 36)is mounted, the presser member being carried by the slide member in the operation of the device. 5. A pressing device according to Claim 4 wherein the two screw- threaded devices (24a, 24b) are carried by the slide member (8) and in turn support the presser member (26). 6. A pressing device according to one of Claims 4 and 5 wherein the slide member (8) also affords part of the support for the binding element (50). 7. A pressing device according to Claim 6 wherein the slide member (8) is afforded by a plate extending at right angles to the base plate (40). > 8. A pressing device according to Claim 7 wherein the slide plate (8) is inclined to the horizontal axis conveniently at an angle of between 30 and 60°. 9. A pressing device according to any one of the preceding claims wherein the two screw-threaded devices are connected together by a flexible endless element (36). 10. A pressing device according to Claim 9 wherein the flexible elongate element is capable of being moved in an adjustment operation by rotation of a wheel (30) of relatively large diameter.

Inventors: WATKINS STEPHEN CHRISTOPHER, WATKINS, STEPHEN, CHRISTOPHER
Applicants: ACCO REXEL GROUP SERVICES PLC, WATKINS STEPHEN CHRISTOPHER, ACCO-REXEL GROUP SERVICES PLC
Application year: 1993
Main classification: B42B5
IPC codes: B42B5