GB2237775A - Drawing aid - Google Patents

Abstract

A drawing aid comprises a template (1) having in at least one surface groove (2) defining outlines any of which can be transferred to a drawing medium (3) on which there is to be prepared a drawing including the selected outline. The transfer is effected by placing the drawing medium (3) on the surface of the template (1) and passing a writing implement (4) over the drawing medium whilst engaged via the drawing medium in the groove defining the selected outline so that the implement is guided by the groove to reproduce the selected outline on the drawing medium. The template is of particular use in drawing ellipses wherein the template includes an array of concentric grooves (Fig. 1). The grooves may be in opposite surfaces of the template. <IMAGE>

Description

DRAWING AIDS This invention relates to drawing aids.

When preparing technical drawings, for example for engineering or architectural purposes, where curved lines have to be drawn these lines can be constructed or recourse can be made to curved stencils. To adopt construction techniques is time consuming. On the other hand, to give the possibility of drawing many different curves a large number of stencils is required. Drawing ellipses presents a particular problem as these are frequently required, especially in perspective views, and a large range of sizes is needed. A further use for stencils is to provide outlines of shapes or symbols that are standard in particular fields.

According to the present invention there is provided a drawing aid comprising a template having in at least one surface grooves defining outlines any of which can be transferred to a drawing medium on which there is to be prepared a drawing including the selected outline, the transfer being effected by placing the drawing medium on the surface of the template and passing a writing implement over the drawing medium whilst engaged via the drawing medium in the groove defining the selected outline so that the implement is guided by the groove to reproduce the selected outline on the drawing medium. As many grooves can be provided adjacent one another in the template, this drawing aid can replace a large number of individual stencils, and, in the case of curves, the need to utilise construction techniques to obtain a desired curve is avoided.

In a particular form where the grooves define a large number of closely adjacent curves, the grooves are in opposite surfaces of the template with each groove that is disposed between two neighbouring grooves being in one surface and the two neighbouring grooves being in the opposite surface.

The drawing aid is particularly suited as an aid for drawing ellipses, where the grooves in the template can represent a large number of closely spaced concentric ellipses.

For a better understanding of the invention and to show how the same may be carried into effect, reference will now be made, by way of example, to the accompanying drawings, in which: Figure 1 is a plan view of a drawing aid; and Figure 2 is a sectional side view illustrating use of the aid of Figure 1.

Referring first to Figure 1, the drawing aid is a template 1 of a transparent plastics material having in one surface an array of grooves 2 defining outlines representing a large number of closely spaced concentric ellipses. In an alternative form the grooves 2 are in opposite surfaces of the template 1 with each groove that is between two neighbouring grooves being in one surface of the template and the two neighbouring grooves being in the opposite surface of the template.

As illustrated in Figure 2, the drawing aid is utilised for drawing a part of or all of any selected one of the ellipses represented by the grooves 2 by placing a drawing medium 3, for example a sheet of paper or plastics film, on that surface of the template 1 that has the selected groove 2 in it, and passing a writing implement 4 such as a pencil over the drawing medium 3 with the tip of the implement 4 engaged, via the drawing medium 3, in the selected groove 2.

Thereby the implement 4 can be made to follow the groove 2 and hence reproduce a curve represented thereby on the drawing medium 3.

Although in the specific embodiment illustrated the grooves 2 represent concentric ellipses of a particular form, it will be appreciated that the array could be of ellipses having a different ratio of major axis to minor axis, or the template could be provided with grooves defining outlines representing curves other than ellipses.

As another alternative, also not illustrated, the template has grooves defining outlines of shapes or symbols that are standard in particular fields, for example chemistry equipment or flowchart symbols.

To aid identification the bases of the curves can be coloured.

Claims (4)

1. A drawing aid comprising a template having in at least one surface grooves defining outlines any of which can be transferred to a drawing medium on which there is to be prepared a drawing including the selected outline, the transfer being effected by placing the drawing medium on the surface of the template and passing a writing implement over the drawing tedium whilst engaged via the drawing medium in the groove defining the selected outline so that the implement is guided by the groove to reproduce the selected outline on the drawing medium.

2. A drawing aid as claimed in claim 1, wherein the grooves define a large number of closely adjacent curves and the grooves are in opposite surfaces of the template with each groove that is disposed between two neighbouring grooves being in one surface and the two neighbouring grooves being in the opposite surface.

3. A drawing aid as claimed in claim 1 or 2, wherein the grooves in the template represent a number of closely spaced concentric ellipses.

4. A drawing aid substantially as hereinbefore described with reference to the accompanying drawings.