GB2046179A

GB2046179A - Lettering Stencil

Info

Publication number: GB2046179A
Application number: GB8010757A
Authority: GB
Original assignee: Rotring Werke Riepe KG
Current assignee: Rotring Werke Riepe KG
Priority date: 1979-04-04
Filing date: 1980-03-31
Publication date: 1980-11-12
Also published as: IT8020923A0; IT1130329B; DE2913529B1; GB2046179B; FR2453029A1

Abstract

A lettering stencil is described which has been produced by injection moulding and has a stencil plate formed with symbol recesses. In order to make the symbol recesses stand out better, each of them is surrounded by contrasting markings which are produced during the injection moulding so that a separate operation previously employed to provide such markings may be eliminated. The markings may take the form of depressions or elevations surrounding the recesses and may have roughened surfaces. <IMAGE>

Description

SPECIFICATION Lettering Stencil This invention relates to a lettering stencil and is particularly concerned with a lettering stencil produced by injection moulding.

It has been proposed to provide a lettering stencil the symbol recesses of which are each surrounded by a contrasting marking, the markings making it easier to recognise the individual symbol recesses and their positioning on the underlying writing surface. The contrasting markings may be formed by colouring the regions adjacent to the symbol cutouts. Thus, in order to produce these contrasting markings, the entire stencil, including the symbol cutouts, has to be produced whereafter the contrasting markings are produced in a separate operation using a colouring matter.

According to the present invention there is provided a lettering stencil, wherein the stencil has been produced by injection moulding, and comprises a stencil plate formed with symbol recesses each of which is surrounded by a contrasting marking formed during the injection moulding of the stencil and clearly distinguishable from the remainder of the surface of the stencil plate. In the production of the present lettering stencil, no separate operation is required in order to produce the contrasting markings as these contrasting markings can be produced during the injection moulding of the stencil.

The contrasting markings surrounding each letter may be formed by a superficial roughness which is clearly distinguished from the rest of the surface of the stencil plate which is preferably polished, and/or by depressions or elevations on one or other of the surfaces of the stencil.

It has already been proposed, in drawing stencils, to provide ink borders formed by depressions surrounding the symbol recesses.

However, these ink borders fulfill a completely different function from the contrast markings of the present stencil; they serve to prevent the ink from running underneath the stencil, but they are provided in stencils in which there is no need to i improve the recognisability of the symbol recesses.

A surface structure of the kind mentioned hereinbefore can easily be produced by correspondingly constructed the walls of the mould used for the injection moulding process or of inserts fixed in the mould, so that the contrast marks are completely finished when the stencil is ejected from the injection mould; in other words, the additional operation required with previously proposed stencils in order to produce the contrast markings is totally eliminated.

Preferably, in one surface of the stencil plate, depressions surrounding the symbol recesses are provided which have roughened surfaces so that these contrast markings are located in regions which are stepped downwards in relation to the rest of the surface of the stencil, and these markings can be produced particularly easily by being placed in inserts in the injection mould corresponding to the surfaces and producing these depressions.

In order to enable the invention to be more readily understood, reference will now be made to the accompanying drawings, which illustrate diagrammatically and by way of example, some embodiments thereof, and in which: Figure 1 is a partial plan view of a lettering stencil, Figure 2 is a partial section along the line Il-Il in Figure 1, to an enlarged scale, and Figures 3 to 6 each show a partial section similar to Figure 2 through some modified embodiments of the lettering stencil shown in Figure 1.

Referring now to Figure 1 there is shown part of a plastics stencil plate formed with symbol recesses in the form of the letters R to Z inclusive, the symbol recess for the letter T being designated by reference numeral 2. All these letters are surrounded by contrasting markings 3 which are shaped essentially to correspond to the shape of the letter, i.e. the symbol recess, and thus frame the associated symbol recess.

As shown in Figure 2, the contrasting markings 3 are provided in depressions 4 which are formed in the upper surface of the stencil plate 1 in Figure 1. These depressions are formed by means of corresponding inserts in the injection mould during the production of the stencil plate and the symbol recesses, and the surfaces of the depressions 4 adjoining the symbol recesses have a different roughness from the remainder of the stencil surface. Since this remaining surface of the stencil is generally polished, the surfaces of the depressions 4 are usually roughened and thus form an optical contrast with the rest of the stencil plate. These roughened portions are obtained by roughening the corresponding surfaces of the inserts in the injection mould.

It should be pointed out that the contrasting markings produced in the injection moulding process do not have to be treated further subsequently, even if the symbol recesses produced by the injection moulding are finished, by milling or the like.

The embodiment shown in Figure 3 is very similar to the embodiment shown in Figures 1 and 2, as symbol recesses, of which the symbol recess 2 can be seen, are provided in the stencil plate 1.

However, in contrast to the embodiment shown in Figure 2 wherein the depression has a region extending parallel to the surfaces of the stencil plate, the surfaces of the depression 4' extend diagonally outwards and towards the surface of the stencil plate. The contrast markings 3' which may again consist of roughened portions are provided in these surfaces.

In the stencil shown in Figure 4, a depression 4" surrounding the symbol recess 2 is formed on the lower surface of the stencil plate 1 and carries contrasting markings 3". This depression is substantially wider than the depression 4 shown in Figure 2 and the depression 4' shown in Figure 3, and in addition to providing optical contrast it may also act as a spacing marking which helps to maintain the correct spacings between the letters which are to be written. Owing to the fact that the depression 4" is located in the lower surface of the stencil plate 1, distortions caused by parallax are avoided.

The embodiment shown in Figure 5 corresponds essentially to the embodiment shown in Figure 4, except that depressions 4"' provided in the lower surface of the stencil plate 1 do not directly adjoin the symbol cutout 2 but are at a small spacing therefrom, so that the contrast markings 3"' do not extend right up to the edge of the symbol recess 2 either. Whilst these depressions may also act as spacing marks, there is the advantage over the embodiment shown in Figure 4 that the writing tip of a writing implement is guided along an edge of the symbol recess 2 which abuts directly on the underlying writing surface, which is not the case in the embodiment shown in Figure 4.

In the embodiment shown in Figure 6, the symbol recess 2 in the stencil plate 1 is surrounded by a rib-shaped bulge 5. There is a different permeability to light in the region of this bulge than in the remainder of the stencil plate and thus a contrast effect is obtained.

Claims

1. A lettering stencil, wherein the stencil has been produced by injecting moulding, and comprises a stencil plate formed with symbol recesses each of which is surrounded by a contrasting marking, formed during the injection moulding of the stencil and clearly distinguishable from the remainder of the surface of the stencil plate.

2. A lettering stencil as claimed in claim 1, wherein the stencil plate has polished surfaces + and the contrasting markings are formed by roughened portions of the surface.

3. A lettering stencil as claimed in claim 1 or2, wherein depressions surrounding the symbol recesses are formed in one of the surfaces of the stencil, the surfaces of such depressions constituting the contrasting markings.

4. A lettering stencil as claimed in claim 3, wherein the depressions providing the contrasting markings are spaced from the edges of the symbol recesses.

5. A lettering stencil as claimed in claim 1 or 2, wherein the contrasting markings are formed by rib-shaped buiges at the edge of the symbol recesses.

6. A lettering stencil as claimed in claim 3, 4 or 5, wherein the surface of each depression or elevation has a surface roughness which is clearly distinguished from the remainder of the surface of the stencil plate.

7. A lettering stencil as claimed in claim 6, wherein the stencil plate has a polished surface and the surface of the depression or elevation is roughened.

8. A lettering stencil substantially as hereinbefore described with reference to Figure 1 and any one of Figures 2 to 6 of the accompanying drawings.