GB2138360A

GB2138360A - Converting printing press to foil-blocking press

Info

Publication number: GB2138360A
Application number: GB08307208A
Authority: GB
Inventors: Harry Cunnington
Original assignee: Norcros Investments Ltd
Current assignee: Norcros Investments Ltd
Priority date: 1983-03-16
Filing date: 1983-03-16
Publication date: 1984-10-24
Also published as: GB8307208D0; GB2138360B

Abstract

An assembly of parts serves to convert an overprinter with conventional printing facility to an overprinter for hot-foil printing. The cam (26) arrangements cooperates with a linkage driven by a drive shaft of the overprinter (normally driving a type cylinder) to effect movement which serves to produce the hot-foil impression on a web (64) passing through the machine and a counter platen (70) is adjustable to ensure that a correct gap is maintained between the web to be printed (64) and a web (62) of hot-foil. Foil is stepped between supply (52) and take-up (54) by cam (26) and linkage (36, 38, 40, 42). <IMAGE>

Description

SPECIFICATION Hoffoil printing This invention relates to hotfoil printing mechanisms for example for incorporation in label overprinters which also incorporate the facility of conventional printing.

Conventional printers employ conventional printing techniques including ink, cliches and soon.

However, overprinters which may be perfectly satisfactory for most uses are not always acceptable in food processing industries where the presence of printing ink is undesirable. The acceptability or otherwise in any given factory can vary appreciably in 15 dependence upon the particular articles to be labelled and overprinted during any given production run. Hotfoil printing is already well established but has the disadvantage that it is appreciably more costly and hence will only be adopted where particularly high 20 quality printing is required or the problems referred to relating to food processing industries arise.

On any given packaging line, it is desirable to install an overprinter on a permanent basis but with cost 25 considerations in mind, it is sometimes a requirement that there should be a quick change operation between conventional printing and hotfoil printing and vice versa.

The novel features of the present invention will be readily apparent from the following description which is given by way of example only, of a label overprinter incorporating the invention, the drawing showing in Figure 1 a side elevation in diagrammatic form of a modification which enables hotfoil printing on a overprinterwhich is primarily intended for conventional printing; and Figure2 is an end elevation showing a detail illustrated in Figure 1.

The mechanism illustrated in the drawings forms part of a label applicator and overprinter which may be of conventional design or incorporating features of the applicator/overprinter of our co-pending application 82.15331 dated 26th May 1982. The overprinter as a whole will incorporate the conventional web reel mounting and a take-up reel as well as a station (not shown) at which the labels are applied. An existing applicator/overprinter will incorporate a typedrum which cooperates with a forme roller neither of which are shown in the drawings. In order to convertthe applicatorwith minimum of modification, the type drum and forme roller are removed although the corresponding spindles coupled to a drive mechanism of the applicator remain in situ.

The spindle 10 would normally carry the typedrum and the spindle 12 would normally carry the forme roller. Grooved collar members 14 are substituted and the grooves thereof engage in edge portions of a slot 16 provided in each of two side plates 18. The side plates 18 are mounted on a base plate 20 and the latter carries a chase 22 and a heater element 24.

The spindle 10 carries an eccentric 26 which bears on rollers 28 mounted on a transverse spindle lying above the base plate 20. A metal pad 30 also contacts the eccentric and is connected to the base plate 20 by upright members 32 (broken lines).

A cam 34 also fast for rotation with the spindle 10 drives a link arm 36 which, through a further link 38, serves to reciprocate over an arcuate path a link arm 40 which serves to index a feed roller 42 through a unidirectional clutch (not shown) on the same shaft as the feed roller 42. The operative stroke of the clutch can be varied by an adjustable stop (not shown) so as to adjust the feed action of the roller 42 and the associated guide roller 44.

A plate 50 serves as a mounting both for the feed roller 42 and for a reel of hotprint foil 52 and a takeup reel for spent foil 54. As is conventional the foil is guided on its path by guide rollers 56, 58 and 60. A horizontal length of the foil path 62 lies immediately below the chase 22.

The label web to be printed has a path running partly in parallel with the path length 62 of the foil and is referenced 64. Inlet and outlet rollers 66 and 68 are disposed immediately upstream and downstream of the horizontal path length 64.

The printing station is, as is conventional, also defined by a platen 70 supported on a block 72, incorporating adjustment screws 74.

After removing the type drum and forme roller and any ink reservoir that may be present the unit is substituted by first fitting the collars 14 to the two existing spindles 10 and 12 engaging the sideplates in the grooves of the collars and fitting the platen 70, correctly adjusted, in its place. A label web is threaded in the normal way and no change to the label web path is necessary. The plate 50 will, of course, be mounted on the over-printer by set screws or other appropriate mounting means (not shown).

In operation the hotfoil printing attachment is switched on to energize the heater 24 and the eccentric 26 will raise and lower the sideplates in cooperation with the pad of material 30 and as the chase reciprocates so the feed of the hoffoil is effected by the cam 34 in cooperation with the linkage 36,38 and 40 and the feed roller 42.

It will be readily apparent that the attachment provided in accordance with the present invention and as hereinbefore described with reference to the preferred embodiment involves a particularly straightforward changeover operation in both directions, there being no change in the web path and the only additional electrical connection required is for the heater.

1. A hotfoil printing mechanism for incorporation in a conventional printing machine having at a print station, means defining a path for a web to be printed, a platen on said path, a type drum spindle, and a form roller spindle, the mechanism comprising a hot print foil supply reel mounting, a spent foil take-up reel mounting, a pair of slotted plates, heater means carried bathe plates, a chase mounted beneath the heater means, the slots of the plates engaging through adapter means on the spindles of the type drum and of the forme roller after the drum and roller have been removed, means mounted on the type drum spindle for reciprocating the plates,

**WARNING** end of DESC field may overlap start of CLMS **.

Claims

**WARNING** start of CLMS field may overlap end of DESC **. SPECIFICATION Hoffoil printing This invention relates to hotfoil printing mechanisms for example for incorporation in label overprinters which also incorporate the facility of conventional printing. Conventional printers employ conventional printing techniques including ink, cliches and soon. However, overprinters which may be perfectly satisfactory for most uses are not always acceptable in food processing industries where the presence of printing ink is undesirable. The acceptability or otherwise in any given factory can vary appreciably in 15 dependence upon the particular articles to be labelled and overprinted during any given production run. Hotfoil printing is already well established but has the disadvantage that it is appreciably more costly and hence will only be adopted where particularly high 20 quality printing is required or the problems referred to relating to food processing industries arise. On any given packaging line, it is desirable to install an overprinter on a permanent basis but with cost 25 considerations in mind, it is sometimes a requirement that there should be a quick change operation between conventional printing and hotfoil printing and vice versa. The novel features of the present invention will be readily apparent from the following description which is given by way of example only, of a label overprinter incorporating the invention, the drawing showing in Figure 1 a side elevation in diagrammatic form of a modification which enables hotfoil printing on a overprinterwhich is primarily intended for conventional printing; and Figure2 is an end elevation showing a detail illustrated in Figure 1. The mechanism illustrated in the drawings forms part of a label applicator and overprinter which may be of conventional design or incorporating features of the applicator/overprinter of our co-pending application 82.15331 dated 26th May 1982. The overprinter as a whole will incorporate the conventional web reel mounting and a take-up reel as well as a station (not shown) at which the labels are applied. An existing applicator/overprinter will incorporate a typedrum which cooperates with a forme roller neither of which are shown in the drawings. In order to convertthe applicatorwith minimum of modification, the type drum and forme roller are removed although the corresponding spindles coupled to a drive mechanism of the applicator remain in situ. The spindle 10 would normally carry the typedrum and the spindle 12 would normally carry the forme roller. Grooved collar members 14 are substituted and the grooves thereof engage in edge portions of a slot 16 provided in each of two side plates 18. The side plates 18 are mounted on a base plate 20 and the latter carries a chase 22 and a heater element 24. The spindle 10 carries an eccentric 26 which bears on rollers 28 mounted on a transverse spindle lying above the base plate 20. A metal pad 30 also contacts the eccentric and is connected to the base plate 20 by upright members 32 (broken lines). A cam 34 also fast for rotation with the spindle 10 drives a link arm 36 which, through a further link 38, serves to reciprocate over an arcuate path a link arm 40 which serves to index a feed roller 42 through a unidirectional clutch (not shown) on the same shaft as the feed roller 42. The operative stroke of the clutch can be varied by an adjustable stop (not shown) so as to adjust the feed action of the roller 42 and the associated guide roller 44. A plate 50 serves as a mounting both for the feed roller 42 and for a reel of hotprint foil 52 and a takeup reel for spent foil 54. As is conventional the foil is guided on its path by guide rollers 56, 58 and 60. A horizontal length of the foil path 62 lies immediately below the chase 22. The label web to be printed has a path running partly in parallel with the path length 62 of the foil and is referenced 64. Inlet and outlet rollers 66 and 68 are disposed immediately upstream and downstream of the horizontal path length 64. The printing station is, as is conventional, also defined by a platen 70 supported on a block 72, incorporating adjustment screws 74. After removing the type drum and forme roller and any ink reservoir that may be present the unit is substituted by first fitting the collars 14 to the two existing spindles 10 and 12 engaging the sideplates in the grooves of the collars and fitting the platen 70, correctly adjusted, in its place. A label web is threaded in the normal way and no change to the label web path is necessary. The plate 50 will, of course, be mounted on the over-printer by set screws or other appropriate mounting means (not shown). In operation the hotfoil printing attachment is switched on to energize the heater 24 and the eccentric 26 will raise and lower the sideplates in cooperation with the pad of material 30 and as the chase reciprocates so the feed of the hoffoil is effected by the cam 34 in cooperation with the linkage 36,38 and 40 and the feed roller 42. It will be readily apparent that the attachment provided in accordance with the present invention and as hereinbefore described with reference to the preferred embodiment involves a particularly straightforward changeover operation in both directions, there being no change in the web path and the only additional electrical connection required is for the heater. CLAIMS

1. A hotfoil printing mechanism for incorporation in a conventional printing machine having at a print station, means defining a path for a web to be printed, a platen on said path, a type drum spindle, and a form roller spindle, the mechanism comprising a hot print foil supply reel mounting, a spent foil take-up reel mounting, a pair of slotted plates, heater means carried bathe plates, a chase mounted beneath the heater means, the slots of the plates engaging through adapter means on the spindles of the type drum and of the forme roller after the drum and roller have been removed, means mounted on the type drum spindle for reciprocating the plates, the heater means and the chase relative to the platen of the machine, and further means mounted on the type drum spindle coupled to a linkage which serves to index the hot print foil web through the machine.

2. A hotfoil printing mechanism for incorporation in a conventional printing machine having a type drum spindle and a forme roller spindle, a printing platen and means for guiding a web to be printed between the type drum and the platen, the mechanism comprising supports for a supply web reel of hotprint foil and for a take-up reel for spent foil, a pair of reciprocable slotted plates, heater means movable with the slotted plates adjacent the path of the hotprint foil through a print station, a chase mounted on the plates and reciprocal with the plates transversely relative to the web path through the print station and to a web to be printed passing overthe platen, the type drum spindle being mounted in the slots of the plates with the aid of adapter means and carrying a cam, a feed roller coupled through a one-way clutch to a linkage actuable bythe cam, guide means for the hotprint foil web between the supply and spent web reels, and means for reciprocating the plates in synchronism with indexing of the hotprint foil through the mechanism.

3. A mechanism according to claim 1 or claim 2, wherein the spindle adapter means comprise collars mounted on the respective spindles which collars act as guides for reciprocal motion of the plates.

4. A mechanism according to claim 1, claim 2 or claim 3 wherein the plates are arranged with the slots therein vertical.

5. A mechanism according to any one of the preceding claims wherein the plate reciprocating means comprises an eccentric mounted for rotation on the type drum spindle, follower rollers rotatably mounted on the plates and in contact with the eccentric, and a pad follower co-operating with the eccentric to maintain the eccentric in contact with the follower rollers.

6. A hotfoil printing mechanism substantially as hereinbefore described with reference to the accompanying drawing.

7. A printing machine incorporating a mechanism according to any one of the preceding claims.