GB2237534A - Printing machine - Google Patents

Abstract

A printing machine for use in hot foil printing and/or gold blocking, which comprises: a support 16 for a workpiece to be printed; a carrier 36 for printing block or other typeface; and a toggle device 33 to provide relative reciprocal motion between the support and the carrier, whereby when the typeface is in position on the carrier the support and typeface can be pressed together so as to print the workpiece. <IMAGE>

Description

PRINTING MACHINE This invention relates to printing machines, and in particular through not exclusively to machines suitable for use in hot foil printing and/or gold blocking.

In a first aspect the invention provides a printing machine for use in hot foil printing and/or gold blocking, which comprises: a support for a workpiece to be printed; a carrier for a printing block or other typeface; and means to provide relative reciprocal motion between the support and the carrier, whereby when the typeface is in position on the carrier the support and typeface can be pressed together so as to print the workpiece, said means including a toggle.

The toggle, which is preferably an elbow toggle, conveniently has an over-centre position which is effected after the typeface and the workpiece have been brought into contact with each other by said reciprocal motion.

By this means the force exerted on the workpiece can be increased substantially after contact of the typeface with the workpiece has been made, whereby improved results can be obtained.

The support can be, for example, a table comprising upper and lower leaves in closely overlapping disposition to each other, the lower leaf carrying level adjustment means whereby the level of the upper leaf with reference to the lower leaf can be adjusted. Preferably, the lower leaf is in a fixed position and the table has securement means whereby the upper leaf can be secured to the lower leaf once said level has been adjusted.

In a preferred form of the invention, the printing machine includes a magnetic sheet, pad or other layer disposed on the support as a means frictionally to support the workpiece thereon. This magnetic layer can be used in conjunction with an L-shaped or other jig to be disposed on the magnetic layer to facilitate alignment of the workpiece with the typeface.

In a second aspect the invention provides a method of printing a substrate in which a printing block or other typeface is mounted for linear reciprocal motion into and out of contact with the substrate, in which said motion is such that the force exerted between the typeface and the substrate rapidly increases once the two have come into contact with each other.

The reciprocal motion referred to herein is conveniently provided, via the toggle, by manual or other operation of a handle operatively connected to the toggle.

There is now described, by way of example and with reference to the accompanying drawing, a printing machine according to a preferred embodiment of the present invention and suitable for use in hot foil printing.

The machine includes a housing comprising a horizontal, rectangular steel base plate (10) from one end of which there extends an upstanding back plate (11). To a midportion of the back plate there are secured by welding two parallel rectangular steel guide plates (12,13).

A vertical rectangular steel side plate (14) is secured by welding both to a vertical edge of back plate (11) and to a first pair of adjacent side edges of plates (12,13). A similar side plate (15) (partly broken away in the drawing for the sake of clarity) extends from the back plate to a second pair of side edges of plates (12,13).

Base plate (10) supports a table comprising upper and lower leaves in the form of horizontal rectangular steel plates (16, 17), the latter plate being supported in a fixed position by two parallel rectangular steel members (18, 19) extending upwardly from the respective side edges of the base plate (10). The lower and upper edges of members (18, 19) are secured to the base plate and to table leaf (17), respective, by welding.

Table leaf (16) is substantially of the same dimensions and as leaf (17)/ is retained in position thereon by securement screws (20) which pass through apertures located in the side region of leaf (16) and are tapped into drilled holes in corresponding side portions of leaf (17). In its four corner portions leaf (17) has drilled and tapped holes which accommodate four adjustment screws (21) the ends of which bear against the underface of leaf (16) and which serve as a levelling means for that plate.

Reference is now made to the means for advancing a printing block or other typeface or impression means towards the table. This means comprises a cranked handle (30) having a horizontally extending portion (31) which is journaled in corresponding, opposed apertures in side plates (14, 15) for rotation about axis (32), the horizontal portion of the handle carrying an elbow-type toggle (33).

The toggle comprises a pair of like parallel members extending orthoganally from the horizontally extending handle portion and having in their outer end portions a pair of opposed apertures in which there is journaled a pivot pin which passes through a link member. The link member has an aperture at the other end thereof which is journaled in a U-shaped bracket rigidly secured to a horizontal support member (34). To the lower face of the support member there are secured by welding two parallel, vertically disposed rods (35) which are a sliding fit in the apertures previously referred to of guide plates (12 and 13) and which, at their lower ends are secured to a heater block (36). The heater block has means on its lower face (not shown) for attaching thereto a printing block carrier.A compression spring (37) is located between the lower face of the plate form and the upper face of plate (12).

In a preferred form of the apparatus the tableleaf (16) has laid thereon a sheet of magnetic rubber on top of which there is placed an "L"-shaped jig which provides a stop for the workpiece. This arrangement facilitates location of the jig at any desired position on the magnetic rubber sheet. As the jig adheres to the sheet under the magnetic force it thereby prevents the workpiece from sliding under it as is the case with some conventional jigs, though the jig may easily be re-positioned manually on the sheet. The sheet provides a resilient support for the workpiece and may readily be replaced when it becomes worn or soiled.

The machine can be operated as follows.

A printing block carrier and its associated printing block is secured to the lower face of the heater block (36) and the workpiece to which the printing block is to be applied is placed on the upper surface of table leaf (16) and manually adjusted so as to be aligned with the printing block.

The handle (30) is pulled manually in direction 'A' causing the horizontal portion of the handle to rotate about axis (32) and operate the toggle in direction 'B', thereby applying a downward force on support member (34) which, together with the rods (35) and the heater block move in a downward direction 'C', thereby overcoming the resistance of the compression spring. This downward motion brings the printing block into contact with the upper surface of the workpiece, and the relative disposition of the workpiece with reference to the heater block is such that the toggle mechanism reaches its overcentre position after this contact has been made. This overcentre position is retained for a time appropriate to effect the necessary printing of the workpiece and then the heater block (together with the carrier and typeface) is withdrawn in an upward direction from the workpiece by manual operation of handle (30).

The printing machine of the embodiment of the invention described above with reference to the accompanying drawing includes a feed mechanism to feed metal or other foil to the typeface. The machine also includes an electric supply to the heater block. Neither of these auxiliary features are shown in the drawing.

It will be appreciated that machines according to the invention can be such that the toggle has no over-centre position or that the distance between the workpiece and the typeface is such that if there is an over-centre position it is not effected during operation of the machine. Thus, the machine can be used in a stamping mode whereby a greater rate of production can be obtained.

Claims (11)

1. A printing machine for use in hot foil printing and/or gold blocking, which comprises: a support for a workpiece to be printed; a carrier for a printing block or other typeface; and means to provide relative reciprocal motion between the support and the carrier, whereby when the typeface is in position on the carrier the support and typeface can be pressed together so as to print the workpiece, said means including a toggle.

2. A printing machine according to Claim 1, in which the toggle is an elbow toggle.

3. A printing machine according to Claim 1 or 2, in which the toggle has an over-centre position which is effected after the typeface and the workpiece have been brought into contact with each other by said reciprocal motion.

4. A printing machine according to Claim 1, 2 or 3, in which the support is a table comprising upper and lower leaves in closely overlapping disposition to each other, the lower leaf carrying level adjustment means whereby the level of the upper leaf with reference to the lower leaf can be adjusted.

5.. A printing machine according to Claim 4, in which the lower leaf is in a fixed position and the table has securement means whereby the upper leaf can be secured to the lower leaf once said level has been adjusted.

6. A printing machine according to any of the preceding claims, which includes a magnetic sheet, pad or other layer disposed on the support as a means frictionally to support the workpiece thereon.

7. A printing machine according to Claim 6, which includes a L-shaped or other jig to be disposed on the magnetic layer to facilitate alignment of the workpiece with the typeface.

8. A printing machine according to Claim 1, substantially as described herein with reference to the accompanying drawing.

9. A printing machine substantially as described herein and substantially as shown in the accompanying drawing.

10. A method of printing a substrate in which a printing block or other typeface is mounted for linear reciprocal motion into and out of contact with the substrate, in which said motion is such that the force exerted between the typeface and the substrate rapidly increases once the two have come into contact with each other.

11. A method according to Claim 10,substantially as described herein with reference to the accompanying drawing.