GB2155863A - Branding apparatus - Google Patents

Abstract

Branding apparatus comprises a head 14, 16; screws 31 which locate and hold a variable array of type faces 17 in-line in the head; electrical heating means 15 to heat the type faces 17 in the head; and a handle 11 which is clad along its length with a heat-insulating plastics coating 12 and which, in use, enables an operator to press the head and its heated type faces against a workpiece. <IMAGE>

Description

SPECIFICATION Embossing apparatus The invention relates to embossing apparatus and is particularly applicable to apparatus suitable for hot foil embossing.

It is known to emboss calendars and other relatively thin sheet card articles by a technique known as hot foil blocking or printing. A printing head contains heated typefaces and is joined to a baseplate. The workpiece, for example a sheet of thin card, is sandwiched together with a suitable foil between the head and the baseplate. Usually the head is pivoted to the baseplate, and moves in an arc to bring the heated typefaces into contact with the foil and the workpiece surface. Preferably there are means to positively clamp the head against the baseplate, and so keep the card and foil under substantially constant pressure, throughout the embossing operation.

Using this known technique, the surface of the workpiece is embossed, and the metallic constituent of the foil is fused and pressed into the embossed areas.

The effect so produced is essentially surface printing. The embossing depth is probably no more than 0.001 inches. If the printed surface was repeatedly rubbed, for example by too frequent handling, the foil would wear away from the embossed areas.

An embossing apparatus embodying the present invention comprises a head, adapted to receive and hold a variable array of embossing typefaces; means to heat the typefaces in the head; a baseplate, preferably unheated and possibly heat-insualted, and means which, in use, locate the baseplate between the head and a workpiece on which the baseplate stands (or against which it is pressed) and which constrain the head to move past the baseplate in order to emboss the workpiece.

With such an apparatus, because the workpiece is not sandwiched between the head and the baseplate, the thickness of the workpiece is immaterial.

It is only necessary for the surface of the workpiece to consist of material suitable for embossing.

The overall size and shape of the workpiece surface similarly are not crucial.

Such an apparatus therefore lends itself ideally to embossing such things as the plastics cases of electronic typewriters, dictating machines, video sets, tape recorders and similarly easily stolen equipment. If the owners house number and postcode, for example, are hotfoil embossed into such articles in a prominent position and in an eyecatching metallic finish, a would-be thief is less likely to take them.

Advantageously the head of the apparatus may be constrained, in use, to move past the baseplate in a substantially straight-line action in order to emboss the workpiece. Greater embossing depths are then possible whilst still resulting in a sharply defined embossed pattern. If, by contrast, the head was constrained to move in an arc, like the head of the known card-blocking press outlined above, the embossed pattern might blurr as the typefaces sank into and out of the workpiece surface.

It is not necessary, within the broadest aspect of the invention, for the head to be permanently located on the baseplate. Indeed it may prove advantageous not to do so, since the heating means and typefaces would more easily be serviced without the baseplate in the way.

The baseplate may advantageously be specifically adapted to locate adjacent the surface of the workpiece. This aids a clean transfer of metallic finish into the embossed areas.

In a presently preferred embodiment of the invention, the baseplate exhibits a through-slot; a foil is located across the slot, in use, via channels in the baseplate; and the head is provided with a heat-insulated handle, is initially separate from the baseplate, and is located thereon in use by spring loaded pegs against which a user pushes the handle to move the typefaces into and through the slot in the baseplate and so emboss the foil into that region of the workpiece surface which is beneath the slot.

Such an embodirnent will now be described vith reference to the accompanying drawings in which: Figures 1 and 2 show the heated head of the apparatus in side elevation and end elevation respectively; Figures 3, 4 and 5 show parts of the head diagramatically; Figures 6, 7 and 8 show the body, which forms part of the head, in side elevation and end elevation and plan respectively; Figures 9 and 10 show the typeface-carrying case, which also forms part of the head, in underplan and end elevation respectively; Figures 11 and 12 show the baseplate in underplan and side elevation respectively; and Figure 13 shows a carrying case for the apparatus.

In figures 1 and 2, a straight circular-section shaft is referenced 11 and is clad along its length with a heat-insulating plastics coating 12 which exhibits finger identations 13 and which functions, in use, as a handle. The shaft projects at right angles from the centre of an initially solid rectangular box-shaped body 14 which carries a 'pencil' heating element 15 and a temperature- sensing probe (not shown): the shaft 11 is made of steel, the body 14 is made of brass.

A case 16, also made of brass, dovetails into a suitably machined recess in the body 14 and carries the variable array of individual typeface blocks 17 which, in use, emboss the desired workpiece.

As shown in Figure 4, each block 17 is of rectangular cross section and is straight and elongate. The blocks 17, like the case 16 and body 14, are made of brass in order to conduct heat most readily from the element 15 to the actual typefaces such as the one 18 indicated in figure 4 and in Figure 1.

As Figure 5 shows, the shaft 11 is externally screwthreaded at each of its opposite ends. It is also hollow throughout its length; one of its ends screwthreads into the centre of the body 14, tight ening into a similarly screwthreaded bore 19, and a temperature-sensing 'pencil' type probe is inserted down the hollow shaft 11 and is a close fit in a bore 21 extending from the base of the blind bore 19.

The bore 21 opens on to the base of the dovetailed recess 22 machined along the length of the body 14. In use, the probe (which is not shown in any of the drawings, but is similar in appearance to the heating element 15) will be inserted as far as the base of the recess 22; and will thus contact the mating base of the typeface-carrying brass case 16.

Figures 6, 7 and 8 show these details.

Also shown in these figures is a channel 23 which runs from the bore 19 down to the bore 24 which houses the heating element 15. In use, as Figure 1 partly illustrates, the twin electrical leads supplying the element 15 are housed in the channel 23 and travel up through the hollow shaft 11 to emerge, together with the probe leads, from the projecting end of the handle.

The brass case 16 is an easily sliding but nevertheless close fit in the body 14. An end plate 25 is screwed to one end face of the body 14 and acts as a backstop when the case 16 is initially slid home. Another end plate 26 is then screwed to the opposite end face of the body 14 to hold the case 16 in the body 14.

A top plate 27 screws down on to the top surface of the body 14 after the heater 15 has been installed in its bore. The plate 27 hides the electrical leads to the heater, and is drilled out centrally to accommodate the shaft 11.

Figure 9 shows the case 16 in underplan. Three channels 28 are machined into its underside. Each is so sized as to take a line of the typefaced blocks 17. Holes 29 are drilled and tapped through one end of the case 16,to open out into these three channels 28. As figure 1 shows, screws 31 enter the holes 29 and, when driven hard against the adjacent end block 17, hold each row of typeface blocks tightly but removably in its casing channel 28.

Four blind holes 32 are drilled one at each opposite corner of the understide of case 16. They project up in to the material of the case, but they do not pass right through it. In use, as will become apparent, they locate the casing 16 (and hence the head as a whole) on the baseplate of the apparatus; which will now be described in detail with reference to Figures 11 and 12.

The baseplate is rectangular in plan, and four pegs 34 project from its corner regions. Each of these pegs is of identical height, and each screws in to a drilled and tapped hole in the base. Each peg has a compression spring 35 coiled around it and these springs 35 project beyond the end of their respective associated pegs.

The springs 35 are a close fit within the blind bo res 32 drilled into each corner of the underside of case 16 and shown in figure 9. A user grasping the handle 12 of the head of the apparatus can thus move the head towards and away from the base plate assembly, against the action of springs 35.

Pegs 34 and springs 35 together with bores 32 constrain the head to move in a straight-line action towards and away from the baseplate.

The baseplate itself is a composite assembly of top plate 36, bottom plate 37 and spacing plates 38. A through-slot 39 is cut out of both the top plate 36 and bottom plate 37, and the spacing plates 38 create side gaps 39A into which a foil sheet can be fitted and located across the throughslot 39.

In use, the baseplate stands on or is pressed against the surface of a workpiece to be embossed.

Typeface blocks 17 are loaded in to the head as illustrated in Figure 1, and the head is located on the baseplate by engaging bores 32 over springs 35. The typefaces are heated, and the user then grasps handle 12 and presses the head against the action of springs 35 towards the baseplate. This moves the typefaces through slot 29 and presses them hard against that region of the workpiece surface which is beneath the slot. Continued pressure embosses the workpiece surface with the foil finish, and the head can then be retracted and if necessary separated from the baseplate assembly by lifting if off springs 35.

The working dimensions and parameters of the apparatus can readily be selected by the man skilled in this particular field. The heating element 15 could for example be a 240 volt 250 watt standard element. The probe could be set to keep the heating element switched on as long as the temperature of the typefaces in casing 16 remain around 150"C. If the temperature rises substantially above that, the probe would automatically cut out the heater, and bring it back in again when the temperature fell below that value. When embossing plastics such as the casing of a transistor radio or dictating machine, these figures might be appropriate, and the embossing depth could lie between 0.001 inches and 0.005 inches.

Suitable foils are already known and need not be described here.

The underside of the bottom plate 37 of the baseplate assembly could exhibit double sided adhesive tape, to help the baseplate stick to whatever surface was being embossed. Suction pads could achieve the same effect. Although individual typeface blocks have been illustrated, it could prove possible to arrange a variable array of typefaces with each line of typefaces carried on a heated rotatable belt or wheel.

The embossed characters need not, of course, be restricted to letters of the alphabet; and the term 'typeface' is to be given a suitably broad interpretation.

In figure 13 a lidded case houses the printing head and baseplate assembly previously described.

The electrical leads to the heating element run out to a junction box which, on its outside surface, incorporates a plug socket 41.

A thermostat 42 allows the user to set a desired temperature for the typefaces and hence to set the probe to govern the output of the heating elements 15 accordingly. Foil sheets 43 are dispensed from a continuous roll, and a tray 44 either lifts out verti caliy or slides out horizontally to give access to the interior of the case for storage and removal of the embossing apparatus.

Mains power is of course fed to the heater of the apparatus from an extension lead plugged in to the socket 41. The electrical leads from the other side of that socket to the heating elements are left sufficiently long for the embossing apparatus to be removed from the casing before being used.

In the apparatus described and illustrated herein, the baseplate components 36, 37, 38 are all made of a suitable heat-insulating plastics material.

Also, in the described apparatus, the embossing depth is set automatically when the projecting ends of pegs 34 come up against the bases of blind holes 32 (or alternatively when the underside of body 14 contacts the top of baseplate 36). Once the appropriate surfaces have come into contact as the head is pushed towards the baseplate, the typefaces cannot sink beyond the predetermined depth.

Claims (9)

CLAIMS 1. Embossing apparatus comprising a head, adapted to receive and hold a variable array of embossing typefaces; means to heat the typefaces in the head; a baseplate, preferably unheated and possibly heat-insulated; and means which, in use, locate the baseplate between the head and a workpiece on which the baseplate stands (or against which it is pressed) and which constrain the head to move past the baseplate in order to emboss the workpiece. 2. Apparatus according to Claim 1 and in which the head of the apparatus is constrained, in use, to move past the baseplate in a substantially straightline action in order to emboss the workpiece. 3. Apparatus according to Claim 1 or Claim 2 in which the head is permanently located on the baseplate. 4. Apparatus according to any of the preceding Claims and intended for hot foil embossing, and characterised in that the baseplate is specifically adapted to locate the foil adjacent the surface of the workpiece. 6. Apparatus according to Claim 5 and in which the baseplate exhibits a through-slot; a foil is located across the slot, in use, via channels in the baseplate; and the head is provided with a heat-insulated handle, is initially separate from the baseplate, and is located thereon in use by spring loaded pegs against which a user pushes the handle to move the typefaces into and through the slot in the baseplate and so emboss the foil into that region of the workpiece surface which is beneath the slot. 7. Apparatus substantially as described herein with reference to and as illustrated in the accompanying drawings. New claims or amendments to claims filed on 13 May 1985 Superseded claims 1 to 7 New or amended claims:- 1 to 9. CLAIMS

1. Branding apparatus comprising a head; means to locate and hold a variable array of type faces in-line in the head; means to heat the type faces in the head; and a handle, not directly heated, and preferably heat-insulated, to press the head and its heated type-faces against a workpiece.

2. Branding apparatus according to Claim 1 and with means to locate and hold a plurality of individual lines of type faces simultaneously in the head.

3. Branding apparatus according to Claim 1 or Claim 2 and in which the means locating and holding, in use, the type faces, comprises a case which, with the type faces in situ, can readily be removed from the rest of the head.

4. Branding apparatus according to Claim 3 and in which the case dovetails into the rest of the head.

5. Branding apparatus according to any of the preceding Claims and in which the line or lines of type faces project, in use, from the head, but the edges of the type faces are spaced from the edges of the head.

6. Branding'apparatus according to Claim 5 and in which the edges of the tykpe faces are spaced from the edges of the head around the whole of the periphery of the head.

7. Branding apparatus according to any of the preceding Claims and in which the means locating the or each line of type faces in the head comprises the opposing sidewalls of a channel, whilst the means holding the type faces in the channel comprises an axially-thrusting releasable clamping means - such as a screw - bearing against an end type face of the line and forcing all the type faces in that line against one another.

8. Branding apparatus according to any of Claims 2 to 7 and in which there is a separate respective end-thrusting clamping means for each line of type faces.

9. Branding apparatus substantially as described with reference to and as illustrated in the accompanying drawings.