GB2190885A - Pictorial reproduction apparatus - Google Patents

Abstract

Pictorial reproduction apparatus comprises a first frame 10 bounding a support area for pictorial matter 12, a slot 19 along each side of the frame, and two rules 13, 14 having slotted ends, studs 18 being slidable in the slots 20 thereof and in respective side slots 19 of the frame. Each rule has a stud 18 in each slot, and the respective studs are received in opposite side slots of the frame. The apparatus also includes a second frame (30, Fig. 2) identical to the first frame, but of double linear dimensions. Using the apparatus, an original picture may be placed on one frame, and a scaled up or down reproduction drawn on a sheet in the other frame by plotting relative co-ordinates of important features determined using the rules with the original. <IMAGE>

Description

SPECIFICATION Pictorial reproduction apparatus This invention relates to pictorial reproduction apparatus to enable accurate reproduction of an original drawing, photograph, or other matter at an enlarged, reduced or equal scaletotheoriginal.

An object ofthis invention is to provide cheap and simple pictorial reproduction apparatus which will enable a userwithoutartisticorgraphic skills two reproduce by drawing, an original atan enlarged, reduced or equal scale, e.g. forthe purpose of making a watercolouror pencil sketch of the content of a photograph or postcard. Accurate freehand copying is difficult even for a skilled artist or draughtsman, and it isparticularly difficult to reproduce the proportions of pictorial matterwhen judging byeyealone, particularlywhen drawing ata different scale to that of the original.

In accordance with this invention, pictorial reproduction apparatus comprises a first frame for mounting an original to be copied, and a second frameformounting a sheetuponwhich a copyisto be made; a first set of co-ordinate determining means associated with the firstframe, for determining co-ordinates of pictorial features on said original, and a second set of co-ordinate determining means associated with the second frame to permit plotting co-ordinates of corresponding possitions offeatures on the respective sheet.

The co-ordinate determining means associated with each frame preferrably comprises a pair of rules, slidably mounted on each frame, and the rules are preferrably graduated in accordance with the ratio of enlargement or reduction; e.g. 2: 1, 3:1 etc., sothatgraduations lmm. apartonthe rules ofthe smallerframe might correspond with graduations 2mm. or3mm apart on the rules ofthe largerframe.

The rules for each frame preferrably comprise a vertical co-ordinate rule having a first stud adapted to slide in a first slot along the upper side ofthe frame, and a second stud adapted to slide in a second slot along the lower side ofthe frame; the rule preferrably having a slot associated with each stud, so that adjustment of the rule in all directions is possible. A second, horizontal co-ordinate rule is similarly provided with two studs, each adapted to slide in a slot one to each side ofthe frame, and in a respective slot in the second rule.At least one, and preferrably both of the rules on each frame may be of sufficient length to extend and measure along the full length ofthe diagonal oftheframe. Preferrably the slots on each side of the frame extend sufficiently beyond each end of the area bounded by the frame to enable the rule to be read from each cornerofthe frame.

The studs may each be secured on the underside oftheframe bya head,and overtheframe byawing nut bearing on the upper surface of the rule.

Theframe and rules maybe made of coloured or clear polycarbonate material, such as 'Perspex', but could of course be made of other materials including wood or metals. Plastics materials however are likely to provide a less expensive product.

The end parts of the rules, in the regions ofthe respective slots in the rules, and the corner areas of the frames may be reinforced and thickened. The margins of the frames may be marked to indicate locations for positioning standard sizes of paper, e.g.

aframe large enough to accomodate B4sheets might provide markings from A4, 85, AS and foolscap sheets.

A preferred embodiment of pictorial reproduction apparatus according to the invention will now be described by way of example with reference to the accompanying drawings, wherein :- Figures I and2 aretogether a plan view ofthe apparatus in use, Figure 1 showing the smaller, and Figure 2 the larger of the frames.

The pictorial reproduction apparatus according to the invention shown in the drawings comprises a first, smallerframe 10 having a rectangular recess or enclosed area 11 for reception of an original drawing or photograph 12, and a second largerframe 30 having a similar recess or enclosed area 31 for reception of a sheet of paper 32 on which an enlarged copy is to be made. In the example shown, the enlargement ratio is 2:1. Of course, a large original may be placed on frame 30, for copying ata reduced scale on a sheet of paper in frame 10.

Frame 10 is provided with a graduated vertical rule 13, and a similar horizontal rule 14. Rule 13 is attached to the frame by a stud 15 received slidably in a slot 16extending along the upperside ofthe frame adjacent the upper edge of the recess 11, and in a shortslot 17 in the upper end ofthe rule. Rule 13 is also attached by a second stud 18 slidably received in a slot 19 extending along the lower side ofthe frame, and in an elongate slot 20 in the lower end of rule 13.Similarly the left hand end of rule 14is attached in the frame bya stud 21 in a slot 22 along the left hand side of the frame and in a slot 23 in that end ofthe rule, and bya second stud 24 in a slot 25 along the right hand side of the frame and in a slot 26 in the right hand end of rule 14. Each slot 20,26 is equal to the difference between the respective vertical or latteral width of the recess 11, and the diagonal dimension ofthe recess.

Each stud, 15,18,21, and 24 has a head bearing on the underside of the frame, a threaded shank extending through the respective slots in the frame and rule, and a wing nut adjustable in tension, so that the relative positions of the stud and the pivot it provides can be moved, ortemporarilyfixed.

The frame 30 has an identical arrangement of rules, slots, and studs, scaled up by a factor of 2.

The apparatus is used by reading co-ordinates on the two rules of the first frame, offeatures of the original pictorial matter, and these are then plotted on the second frame using the corresponding magnified measures on the rules on the second frame, to locate features on the sheet in the second frame, and by building up the plotting of reference points two enable connecting lines and minorfeatures to be added free hand at the user's discretion, whilst transferring the proportions of the original pictorial mattertothe enlarged (or reduced) copy. Reduction is effected by putting the original in the second frame and making the copy in thefirstframe.

The corner regions of the frames, and the ends of the rules aboutthe slots are made thickerthan the other parts of the frames and rules. e.g. by laminating an extra layer of plastics in the process of manufacture. The apparatus is made of clear or coloured synthetic plastics such as polycarbonate, e.g. 'Perspex', but couid within the scope of the invention be made of any rigid sheet materials with a measure of resilient flexibility such as metal or wood.

The apparatus can be used for example for producing drawings from photographs or post cards for subsequent colouring or inking, etc.. It is also more accurate than the use of pantographs where slipping may occur, and to avoid excessive pressure by a stylus which may damage an original.

Claims (8)

1. Pictorial reproduction apparatus comprising a firstframe for mounting an original to be copied to an enlarged orreduced scale, and a secondframefor mounting a sheet upon which a copy is to be made; a first set of co-ordinate determining means associated with the first frame, for determining the co-ordinates of pictorial features on said original, and a second set of co-ordinate determining means associated with the second frame to permit plotting co-ordinates of corresponding features upon the respective sheet.

2. Apparatus according to Claim 1, wherein each set of co-ordinate determining means comprises a pair of rules, slidably mounted on each frame, the rules of one set being graduated in units largeror smallerthan corresponding units of graduation on the other set, in accordance with the ratio of enlargement or reduction between the frames.

3. Apparatus according to Claim 2, wherein each frame is provided with a vertical co-ordinate rule having a first stud adapted to slide in a first slot along the upper side of the frame, and a second stud adapted to slide in a second slot along the lower side oftheframe,the rule also having a slot associated with each stud; and a second, horizontal co-ordinate rule also provided with a stud towards each end, each adapted to slide in a slot in the respective side of the frame, and in the respective end ofthe rule; the terms 'vertical', 'horizontal', 'upper' and 'lower' only relating to the usual orientation of a picture in the frame, and not to any absolute spatial orientation.

4. Apparatus according to Claim 3, wherein at least one, and preferrably both of the rules on each frame are of sufficient length to extend and measure along thefull length ofthe diagonal oftheframe.

5. Apparatus according to Claim 3, wherein the slots along each side ofthe frame extend sufficiently beyond each side of the area bounded by the frame to enable readings to be taken from the cornerwhen the rule is extended diagonally.

6. Apparatus according to any one of Claims 3,4, or 5 wherein the studs are each secured on the underside ofthe frame by a head, and overtheframe by a wing nut bearing on the upper surface ofthe rule.

7. Apparatus according to Claim 3, or any Claim appendant thereto,wherein the end parts ofthe rules, about the respective slots, and the corners of the frames are made of greater thickness than the remainder ofthe rules and frames respectively.

8. Pictorial reproduction apparatus substantially as hereinbefore described, with reference to and as illustrated in the accompanying drawings.