The present invention relates to a machine for decorating metal plaquettes.

Decorating machines for mental plaquettes are known consisting substantially of two heating plates hinged together along an edge. A removable template comprising a plurality of holes corresponding to the shape of the plaquettes to be decorated rests on one of the heating plates.

The decoration step involves resting on the lower plate a sheet on which the decorations to be transferred are printed, positioning the template on said sheet, placing the plaquettes in the template holes; applying a further sheet provided with decorations, and then rotating the other plate to transfer the decorations onto the plaquette coating.

However these known machines are designed for large production and are therefore unsuitable for decorating a small number of plaquettes, and consequently unsuitable for small activities such as shops.

These machines also present the drawback of unreliable precision during the closure of the heating plates due to the wide opening of the hinged plates.

Finally these machine are difficult to adapt to different plaquette thicknesses because of their hinging.

US-A-4 664 672 discloses a process for transfer printing onto solid substrates made of plastics or having a surface layer of varnish or plastic . A sheet dye carrier is pressed at a temperature suitable for dye transfer to a preferably preheated surface and/or to a limited area of the surface to be printed by means of superatmospheric gas pressure, in particular by means of a flowing gas. Additionally, the surface to be printed is maintained at a temperature below the thermoplastic range during the transfer process.

US 2002/069772 A1 discloses an imaging system having a housing with an interior chamber a press, and a door. The press has a base fabricated of a rigid material and with an upper surface and further has a raisable platen with a lower surface fabricated of a resilient material. A support plate is positionable on the upper surface of the base for the receipt of an object. A transfer sheet has printing material to be positioned upon the object. Drive mechanisms urge the platen downwardly into contact with the transfer sheet with the object, plate and base there beneath.

JP-A-54 033 113 describes a method of decorating by sublimation a substrate placed between the two edges of a folded transfer sheet containing the image to be reproduced.

An object of the invention is to eliminate the drawbacks cited above by providing a decorating machine for metal plaquettes which is of very simple use, including for small quantities.

Another object of the invention is to provide a decorating machine able to decorate plaquettes of different thickness.

These and other objects which will be apparent from the ensuing description are attained according to the invention by a decorating machine for plaquettes as described in claim 1.

A preferred embodiment of the present invention is further clarified hereinafter with reference to the accompanying drawings, in which:

Figure 1

is a perspective view of a decorating machine according to the invention during application of the decorative sheet,

Figure 2

shows it in the same view as Figure 1 during application of the plaquette,

Figure 3

shows it in the same view as Figure 1 during decoration.

As can be seen from the figures, the decorating machine of the invention comprises substantially a base 2 provided with a column 4 supporting a first heating plate 6 via a rack device (not shown in the figures) and operable vertically by a lever 8. A second heating plate 10 is provided in a position below the heating plate 6 to form a gap 12 with the overlying heating plate 6.

A support panel 16 comprising two pegs 20 on its upper surface is hinged to the base 2 about a pin 14 and is provided with an operating handle 18 for its insertion into the gap 12.

The invention also comprises a template 22 provided with two elliptical seats 24 provided on its edge with protuberances 26 the function of which is clarified hereinafter.

The template 22 is provided with holes 28 spaced apart by a distance corresponding to the distance between the pegs 20 of the panel 16 and comprises an operating handle 30.

The invention uses a sheet of sublimation paper 32 with a pre-creasing line 34 forming two portions 36, 36', each of which is provided with two pairs of holes 38 which, when the two portions face each other, are coaxial, their distance apart corresponding to the distance between the pegs 20.

One of the surfaces of the sheet 32 is provided with pairs of images 40 obtained by sublimation image printing techniques and positioned relative to the holes 38 in the same manner as the elliptical seats 24 are positioned relative to the holes 28 in the plate 22.

The plates 6 and 10 are protected by a protection grid 44.

At the rack there is also provided a screw adjustment system (not shown in the drawings) to define the position of a lower stop for the upper heating plate, in this position a switch being provided for activating the heating plates.

In using the decorating machine of the invention, the panel 16 is rotated about the pin 14 to position it outside the range of action of the plates 6 and 10, then the sheet is applied to it with the two portions 36, 36' at 180° apart by inserting the pegs 20 into the holes 38 of the portion 36. The template 22 is then mounted on the portion 36 by inserting the pegs 20 into the holes 28, and the plaquettes 42 to be decorated, previously treated with a special coating, are inserted into the seats 24.

The portion 36' is then rotated through 180° so that the portions 36 and 36' face each other. Then after rotating the lever 18 to insert the panel 16 into the gap 12 the plate 6 is lowered by the lever 8, then as soon as the plate 6 interferes with the activation switch both the plates 6, 10 are heated.

As a result of the heating action of the plates 6 and 10 the images 40 impressed into the sheet 32 are transferred by sublimation onto both surfaces of the plaquettes 42, the ink also being transferred onto the plaquette edges by virtue of the presence of the protuberances 26 present on the edge of the seats 24 which create an empty annular space.

From the aforegoing it is apparent that the decorating machine of the invention presents certain advantages, and in particular:

• it enables metal plaquettes such as key fobs, key heads etc. to be decorated in a personalized manner,
• it enables reliable centering,
• it enables the plaquette edges to be decorated,
• it is of high reliability during use,
• it enables plaquettes of different thickness to be decorated.