GB2224695A - Paper guiding accessories for selective printers - Google Patents

Abstract

The guide comprises a bridge member supported at each end by a leg attachable to a printer housing, the legs being adjustable in their separation to accommodate to the size of the housing, and the bridge bearing a number of paper guides which are adjustable in position therealong. As described, each leg terminates in a foot which is releasably securable to a shoe (e.g. by toggles), and the shoes are securable to the printer housing (e.g. by self adhesive strips). The bridge member may be rotatable about its lengthwise direction to enable the inclination of the guides to be adjusted. The paper guides may comprise carriers slidable along the bridge and guide plates adjustably mounted on said carriers. At least the outer plates preferably bear fences. <IMAGE>

Description

PAPER GUIDE This invention relates to a paper guide, and more specifically to a paper locating, aligning and/or guiding device for a computer printer.

Computer printers providing output data use continuous stationery of the kind in which holes punched along the respective side portions of the paper are engaged and driven by sprocket wheels carried at the respective ends of the printer platen. The continuous paper is thus always properly located, aligned and guided relative to the platen, so that the printed data appears in proper position and alignment on the paper.

However, in general such printers lack an effective means for locating, aligning and guiding cut sheets of paper (e.g. of A4 size, as is commonly used now in business correspondence) relative to the platen, and maintaining such paper sheets in proper alignment as they are drawn into the printer by the rotating platen.

The use of small personal computers for word processing often requires the computer output to be printed on cut sheets of paper. Hence, the lack of adequate means for locating, aligning and guiding the cut sheets as they are drawn around the platen results in the need for excessive care in manually locating and aligning the cut sheets relative to the platen, otherwise the paper sheets will enter the printer at an incorrect position on the platen and/or in a skewed manner.

According to the present invention, a paper guide for locating, aligning and/or guiding cut sheet paper relative to the inlet side of a computer printer platen comprises: (a) a bridge adapted to transversely span the platen and comprising (i) a transverse bridge member and (ii) at least two feet secured on the bridge member and adapted to engage and be secured to respective free surfaces of the casing or other part of the printer, one of the feet being releasably secured on and movable along the bridge member thereby to permit the transverse spacing of the feet to be adjusted to suit the transverse spacing of the respective free surfaces, and the feet providing a working clearance for the bridge member over the spanned part of the printer, and (b) at least two paper supports carried on the bridge member and arranged for positioning at transversely spaced locations such as to suit the width of the cut sheet paper to be fed to the platen, which supports have an inclination such as to direct cut sheets supported thereon towards the knip-point of the platen with its associated paper gripping rollers, and at least one such paper support carrying an upstanding paper guide or fence for locating a cut paper sheet transversely on the paper supports.

According to one preferred feature of the present invention, the paper guide includes at least two shoes arranged for positioning and securing on the respective said free surfaces of the printer, each such shoe being arranged to receive therein the base part of one said foot, and each shoe being provided with a releasably locking means for releasably securing the foot in the shoe, thereby to permit the bridge to be secured to and removed from the printer as and when required.

According to another preferred feature of the present invention, the paper guide includes a beam rotatably carried on said bridge member with its rotational (i.e.

longitudinal) axis parallel with the rotational axis of the platen, and beam locking means for releasably locking the beam in a selected angular position relative to the bridge thereby to ensure entry of each cut sheet to the platen at a predetermined entry angle; and said paper supports are adjustably carried on said rotatable beam.

According to yet another preferred feature of the present invention, each said foot has a connecting head for securing the foot to the bridge member, and said connecting head is offset in a direction normal to the bridge member relative to the base of the foot, thereby to enable the position of the base of the foot to be changed, in that direction, relative to the bridge member by reversing the foot.

According to yet another preferred feature of the present invention, each said shoe has a base arranged for securing on a said free surface of a printer, and a socket for receiving therein the base of a said foot, and said shoe base and said shoe socket are offset in a direction normal to the bridge member, thereby to enable the position of the shoe socket to be changed, in that direction, relative to the shoe base by reversing the shoe.

According to still another preferred feature of the present invention, each paper support comprises a carrier which is slidably carried on the beam, and a paper support plate which is adustably carried on the carrier so that its position on the carrier in the direction of paper feed may be adjusted to provide support for paper sheets at a position closely adjacent the entrance to the platen.

Thus, as the angle of the beam is adjusted to suit any particular printer configuration, the paper support plates may be appropriately adjusted in their longitudinal directions to provide paper support as near as possible to the paper entrance to the platen.

Preferably, one other paper support also carries thereon a further paper guide or fence, thereby to locate and guide a cut sheet at both of its lengthwise boundaries.

Other features of the present invention will appear from a reading of the description that follows hereafter, and of the claims appended at the end of that description.

One cut-sheet locating, aligning and guiding device (hereinafter referred to for the sake of simplicity as a 'cut sheet guide' or a 'paper guide'), and various modifications thereof, all according to the present invention, will now be described by way of example and with reference to the accompanying pictorial and diagrammatic drawings. In what follows, the terms 'front', 'back', 'rear', 'left', 'right', etc. all refer to the paper guide as viewed by the operator of a printer on which the paper guide is mounted.

In those drawings: Figure 1 shows the right hand end of the paper guide as seen obliquely from the rear; Figure 2 shows an obliquely upward view of bridge, foot and shoe parts of the paper guide as seen from the front, with the bridge part cut short to the left of the leg and shoe parts so as to show the cross section of the bridge part; Figure 3 shows an obliquely downward view of the right hand end of the paper guide as seen from the front, with a rotatable beam part of the guide removed; Figure 4 shows an obliquely downward view of the right hand end of the guide as seen from the front, with a paper support plate removed; Figure 5 shows an oblique view of the left hand end part of the paper guide as seen from the right; Figure 5A shows a transverse cross section of a rotatable beam part of the paper guide; ; Figures 6 and 7 show diagrammatically an end view as seen from the right hand side of a printer carrying the paper guide, to illustrate different configurations of printer platen and paper guide, the paper guide being constructed so as to accommodate both extreme configurations; Figures 8A and 8B show diagrammatically front views of the printer platen and the paper guide, to demonstrate the possibilities for adopting different spacings of the feet of the paper guide, Figure 8B being an enlargement of part of Figure 8A; Figure 9 (a) shows diagrammatically in end view one foot and its associated shoe of the paper guide, whilst Figures 9 (b) to (d) demonstrate the possibilities for removing the paper guide from the respective shoes in three different directions so as to avoid different obstructions that may be present in or adjacent the printer;; Figures 10 (a) to (c) show diagrammatically in front view one foot of the paper guide seated in it associated shoe, the shoe being shown in the respective Figures secured on respective fixing surfaces of a printer which are disposed at three different angles, whilst Figure 10(d) shows an enlargement of the arrangement shown in Figure 10(c); Figures 11 (a) to (d) show diagrammatically in end view one foot and its associated shoe, to demonstrate the possibilities for varying the position of the upper end of the foot relative to a given shoe fixing position on the printer; Figures 12 (a) to (c) show diagrammatically in front view a paper support plate, to demonstrate the possibilities for varying the position thereon of an upstanding paper fence or guide; Figure 13 shows a pictorial view of the assembled paper guide;; Figure 14 shows a pictorial view of the assembled paper guide secured in position on the upper part of a computer printer, above the printer platen; Figure 15 shows a pictorial view of a computer printer with the paper guide secured in position on the upper part of the printer, above the printer platen, but with only short paper guiding members; Figure 16 shows a part-sectional side elevation looking in the direction of the arrow XVI shown in the Figure 13; Figures 17 and 18 show respective side elevations of one of the feet of the paper guide and an associated shoe in which the foot is received (likewise looking in the direction of the arrow XVI shown in the Figure 13), which side views serve to illustrate alternative positions for the foot in the shoe, and in chain-dotted form the manner in which the foot may be removed from the shoe; and Figure 19 shows a part-sectional side elevation through a bridge portion of the paper guide, again looking in the direction of the arrow XVI shown in the Figure 13.

Referring now to the drawings, the paper guide there shown comprises a bridge 10 which is intended to be mounted on a printer (not shown) at a position above and to the rear of the printer platen 12 (Figures 6 and 7). The bridge comprises a transverse member 14 (an aluminium extrusion) of a generally W-shaped cross section which is best shown in the Figure 2, and two transversely spaced supporting feet 16 of a plastics material. (In the description that follows, unless otherwise specified, all parts comprise injection mouldings of a suitable plastics material.) Each such foot has a head portion 18 engaged in a bottom-opening central slot 20 of the transverse member 14, and a transversely slidable wedge 21 for tightening the engagement of that head portion in the slot 20 whereby to lock the foot in a desired position on the transverse member.The wedge is held in the wedged position by resiliently mounted knibs 22 which engage around the front faces of transverse webs 23 formed on the sides of the foot.

Withdrawal of the wedges from the feet frees them for movement along the transverse member 14. Thus, in assembling the paper guide for a particular printer the feet may be positioned on the transverse member at any convenient positions to suit the fixing positions that are available on that printer. There is thus a freedom of choice in selecting the positions on the printer structure to which the feet are to be fitted. This freedom is illustrated in the diagrammatic line diagrams of Figure 8, where selected feet positions are shown in full lines, and typical alternative feet positions are shown in dotted lines. Having selected suitable positions on the printer, the feet are simply spaced apart at the requisite positions on the transverse member 14, and the wedges 21 are then inserted and moved home whereby to lock the feet at the selected positions.

Each foot 16 has a base portion 24 which sits in a channelshaped shoe 26 and is retained therein by two over-centre toggle devices 28, 30 which are clipped onto respective transverse pins 32 carried in the respective shoes and which engage toe and heel portions 24A and 24B respectively of the foot.

Each shoe 26 is provided on its underside with a pad 26A of a double-sided self-adhesive tape by means of which, after first removing the conventional protective covering from the lower surface of the pad, the shoe can be securely affixed at a suitable position on an appropriate surface of the printer casing or other structure. Such position will be determined having regard to the various possibilities for adjustment of the relative positions of the shoes and the transverse member 14, which possibilities are described below.

The bridge carries at each end an end cap 34 which is secured by screws 36 screwed into respective slots 38 of the transverse member 14, as is best shown in Figure 3.

The end caps have central bearing holes 40 for receiving respective bearing screws 42 which are themselves screwed into the respective ends of a rotable beam 44 which is positioned between the end caps. The beam 44 is thus rotatably carried on the bridge 10, and can be angularly adjusted to any selected position. Rotation of the beam is impeded by frictional resistance, so that once positioned as required, that angular position will be maintained until forcibly moved therefrom. Other means for releasably locking the beam against fortuitous rotation may be provided instead or in addition.

The beam 44 comprises an aluminium extrusion having a hollow D-shaped cross section, the plane part 46 of which has internally a projecting rib 48 which defines a centrally positioned slot 50, and externally two spaced and oppositely-directed rails 52, 54 between which is disposed a scale 55 for aiding the user of the printer. Those rails constitute a slideway upon which are carried two or more paper supports 56, 58.

Each paper support includes a runner or carrier 60 having on its underside two spaced, inwardly-facing slots 62, 64 in which are engaged the respective rails 52, 54 of the beam 44, and on its upper side two transversely spaced, fore-and-aft members 66, 68 each of which defines a groove 70, 72. Each runner also carries a pivoted lever 74 which is arranged for operation between engaged and released positions whereby to operate a clamping member 76 arranged for releasably engaging the upper rail 52 of the beam whereby to lock and release the runner on the beam.

Each runner or carrier 60 supports a paper support plate 78 which has an upper, plane, paper-support surface 80, and which has projecting from its lower surface two parallel rails 82. Those rails frictionally engage in the respective grooves 70, 72 of the runner, the mating surfaces of the rails and grooves being slightly tapered to provide a good but releasable engagement of the support plate on the runner. It will be appreciated that the position of each support plate on its associated runner can be adjusted longitudinally to give paper-support as near as possible to the entrance port (92 in the Figure 6 or 94 in the Figure 7) the printer platen, so that the paper is guided specifically to the knip-point 98 of the platen with its associated paper-gripping rollers 100.

Each paper support plate 78 is provided with a series of parallel rows of narrow slots 84, into any one of which rows may be secured an upstanding paper fence or guide 86 for locating, aligning and guiding a cut paper sheet.

Hence, the fences may be readily positioned to provide the desired location of the paper being fed to the platen.

This is illustrated in the Figures 12 (a) to (c).

Whilst there may be provided more than two paper supports for supporting a very wide cut paper sheet across its width, only the endmost supports will be provided with paper guiding fences 86.

Each foot 16 of the bridge is assymetrical as seen in an end view of the paper guide, so that its upper end does not lie directly over the centre of its base. As a result, turning the feet around relative to their shoes has the effect of moving the point of attachment of each foot to the transverse bridge member 14 in the fore-and-aft direction relative to its point of fixing on the printer.

This provides some flexibility in fitting the paper guide to any given computer printer, thus allowing the use of the best fixing points for the shoes on the printer structure, whilst giving the best location of the bridge, beam and associated paper supports relative to the printer platen.

This is illustrated in the diagrams of the Figures 11 (a) to (d), where the supporting surface of the printer is indicated at 87.

Moreover, each shoe is assymetrical in its fore-and-aft direction, in that the toggles and their respective toggle pivots are displaced from a central disposition in the shoe. Hence, reversing the shoes end-for-end provides further flexibility in fitting the paper guide to the printer casing or other structure, thereby to achieve a proper working relationship between the paper guide and the printer platen.

Furthermore, the offset in the feet in combination with the opportunity to release either or both toggle members 28, 30 in the respective shoes 26 provides various possibilities for lifting the bridge, beam and paper supporting parts as a complete unit clear of the printer and any adjacent obstructions. This is illustrated in the line diagrams of the Figures 9 (a) to (d).

The base of each foot is constituted by a shallow V-shaped bearing surface 88 having a fore-and-aft ridge 90, as illustrated diagrammatically in the line diagrams of the Figures 10 (a) to (c). As shown in those diagrams, the feet can stand stably in their respective shoes even when those shoes are secured on slightly sloping parts of the printer (machine) structure.

Moreover, the base of each foot is tapered in the fore-andaft direction as seen in plan view. This allows for slight inaccuracies in the fore-and-aft alignment of the shoes when fixed on the printer.

The features described above enable the present paper guide to be fitted to many different printers, regardless in most cases of the relative dispositions of the printer platen and the port or entrance in the printer structure for paper being fed to the platen. The diagrams of Figures 6 and 7 illustrate such dispositions for two different printers.

In the arrangement of Figure 6, the paper entry port 92 is close to and almost directly above the platen, so that the papers enters the port at a very steep angle; whereas in the arrangement of Figure 7, the paper entry port 94 is disposed some way to the rear of the platen, so that the paper enters at a very shallow angle. In those Figures, the paths of the paper are indicated by the reference 96.

To meet such variation in printer construction, the present invention provides a paper guide in which the following parameters can be readily changed to suit the printer construction, namely (a) the angle of the paper support plates on the bridge, (b) the position in a fore-and-aft direction of the paper support plates relative to the bridge, (c) the transverse positions on the bridge at which the paper support plates are located, (d) the position of the bridge relative to the available fixing positions on the printer structure for receiving the bridge feet, and (e) the transverse positions on the bridge at which the feet may be fixed.

Moreover, the present invention provides a paper guide which can (i) readily accommodate variations in the inclinations of the surfaces available on the printer structure at which the bridge feet are to be located, (ii) be readily removed as a whole from its position on the printer (by releasing the toggles devices in the respective shoes, thereby freeing the feet for lifting out of the shoes) for giving access to parts of the printer, and be readily reinstated when required, and (iii) be readily fitted to a printer without the use of fixing screws or other mechanical fixing devices and tools.

The bridge feet are proportioned so as to ensure adequate working clearance between the upper parts of the printer and the transverse bridge member 14 and its associated parts.

Further technical details concerning the construction, fitting and operation of the paper guide will be gleaned from the accompanying two technical leaflets, which leaflets are incorporated in this specification by this reference to them.

Claims (15)

1. A paper guide for locating, aligning and/or guiding cut sheet paper to be fed to the inlet side of a computer printer platen, which guide comprises: (a) a bridge adapted to transversely span the platen and comprising (i) a transverse bridge member and (ii) at least two feet secured on the bridge member and adapted to engage and be secured to respective free surfaces of the casing or other part of the printer, one of the feet being releasably secured on and movable along the bridge member thereby to permit the transverse spacing of the feet to be adjusted to suit the transverse spacing of the respective free surfaces, and the feet providing a working clearance for the bridge member over the spanned part of the printer, and (b) at least two paper supports carried on the bridge member and arranged for positioning at transversely spaced locations such as to suit the width of the cut sheet paper to be fed to the platen, which supports have an inclination such as to direct cut sheets supported thereon towards the knip-point of the platen with its associated paper gripping rollers, and at least one such paper support carrying an upstanding paper guide or fence for locating a cut paper sheet transversely on the paper supports.

2. A paper guide according to claim 1, including at least two shoes arranged for positioning and securing on the respective said free surfaces of the printer, each such shoe being arranged to receive therein the base part of one said foot, and each shoe being provided with a releasably locking means for releasably securing the foot in the shoe, thereby to permit the bridge to be secured to and removed from the printer as and when required.

3. A paper guide according to claim 1 or 2, including a beam rotatably carried on said bridge member with its rotational (i.e. longitudinal) axis parallel with the rotational axis of the platen, and beam locking means for releasably locking the beam in a selected angular position relative to the bridge thereby to ensure entry of each cut sheet to the platen at a predetermined entry angle, and wherein said paper supports are adjustably carried on said rotatable beam.

4. A paper guide according to claim 2 or 3, wherein each said foot has a connecting head for securing the foot to the bridge member, and wherein said connecting head is offset in a direction normal to the bridge member relative to the base of the foot, thereby to enable the position of the base of the foot to be changed, in that direction, relative to the bridge member by reversing the foot.

5. A paper guide according to claim 2, or claim 3 or 4 when dependent on claim 2, wherein each said shoe has a base arranged for securing on a said free surface of a printer, and a socket for receiving therein the base of a said foot, and wherein said shoe base and said shoe socket are offset in a direction normal to the bridge member, thereby to enable the position of the shoe socket to be changed, in that direction, relative to the shoe base by reversing the shoe.

6. A paper guide according to claim 3, or any later claim when dependent directly or independently on claim 3, wherein each paper support comprises a carrier which is slidably carried on the beam, and.a paper support plate which is adustably carried on the carrier, so that its position on the carrier in the direction of paper feed may be adjusted to provide support for paper sheets at a position closely adjacent the entrance to the platen.

7. A paper guide according to claim 6, wherein each paper support plate is frictionally gripped in one or more longitudinal grooves provided in the carrier.

8. A paper guide according to claim 7, wherein each paper support plate is frictionally gripped in said grooves by inter-engagement of lightly tapered parts formed on the support plate and carrier respectively.

9. A paper guide according to claim 2, or any later claim as dependent directly or indirectly on claim 2, wherein each foot is releasably secured in its associated shoe by respective over-centre toggle members carried at or near the respective fore and aft ends of the shoe, thereby to permit removal of the bridge from the shoes in different directions to suit the configuration of the particular printer on which the bridge is mounted and obstructions that are present adjacent the printer.

10. A paper guide according to claim 2, or any later claim as dependent directly or indirectly on claim 2, wherein the base of each foot comprises two mutually-inclined surfaces which intersect at a fore-and-aft ridge whereby to enable the feet to sit firmly in their respective shoes even when the said free surfaces carrying said shoes do not lie in a common plane.

11. A paper guide according to claim 2, or any later claim as dependent directly or indirectly on claim 2, wherein the base of each foot is tapered in the fore-and-aft direction thereto allow for inaccuracy in the fore-and-aft alignment or positioning of the respective shoes on the printer casing or other structure.

12. A paper guide according to claim 2, or any later claim as dependent directly or indirectly on claim 2, wherein each shoe member has secured to its base a double-sided adhesive pad for securing the shoe on a said free surface of the printer.

13. A paper guide according to any preceding claim, wherein at least one other paper support carries thereon a further paper guide or fence, thereby to locate, align and guide a cut paper sheet at both of its opposite, lengthwise edges.

14. A paper guide substantially as hereinbefore described with reference to and as illustrated by the accompanying diagrammatic drawings.

15. A paper guide comprising any operable combination of various features described in this specification, other than a combination as claimed in any preceding claim.