WO1983002080A1

WO1983002080A1 - A process for reproducing products, and apparatus for carrying out the said process

Info

Publication number: WO1983002080A1
Application number: PCT/SE1982/000412
Authority: WO
Inventors: & Thornberg Ab Dahlström
Original assignee: Thornberg, Anders
Priority date: 1981-12-11
Filing date: 1982-12-02
Publication date: 1983-06-23
Also published as: EP0096060A1; SE8107424L

Abstract

A process for manufacturing products such as casting moulds and patterns, for example, and apparatus for carrying out the process. The invention enables the production of products such as casting moulds and patterns, for example, to be simplified. By using a plurality of templates (3) appertaining to a template system, the extent of every single line (2; 2<1>) such as the curves which the product contour displays, for example, is determined, and is depicted and/or reproduced at any stage during the manufacturing process, as desired. The similarity of the curve to a template (3) which fits it is thereby determined, and the extent of the curve (2; 2<1>) is also defined over the said template (3) which fits it, between a plurality of points (A1; A2, etc.) which are locationally defined on the template.

Description

A Process for reproducing Products, and Apparatus for carrying out the said Process.

The present invention relates to a process for reproducing products, such as casting moulds and patterns.

The invention also relates to apparatus for carrying out the process. At the present time there are curve templates for draft ing work on the market. These can only be used to indicat and show a curve which is not fixed in advance, and therefore neither can it be directly reproduced at later stages in the production process, up to the finished part. Figure1 shows an example of how the dimensions of a product which has a curved surface have been indicated up to the present time. When manufacturing products such as casting moulds and patterns, for example, it was necessary formerly either for a template to be produced for each such curve on the drawing, or the curve had to be read off with the aid of a laser, for example, and stored in a digital memory.

The templates were then used, as a basis and aid in the manufacture of patterns and tools, while the digital memory could be used to control an NC milling machine, for example. The object of the present invention is primarily to provide a process of the type mentioned above which enables the production of products such as casting moulds and patterns, for example, to be simplified.

This object is achieved with a process according to the present invention which is primarily characterised in that the path of every single line, such as the curves which the contour of a product displays, for example, and which it is desired to depict and/or reproduce at any stage of the production process, is determined by means of a plurality of templates appertaining to a template system, and that the similarity of the curve path to a template which fits it is thereby determined, and that the length of the curve is defined over the said template which fits it, between a plural ity of specifically located points on the template. A further object of the present invention is also to produce apparatus for carrying out the process.

The said further object is achieved with apparatus according to the present invention which is primarily characterised in that a template system contains a plurality of templates with various curves, and along each of the curve paths on the respective templates there are indications of location, such as millimetre graduations over the template curve, for example.

The invention is described in the following by way of an example, with reference to the accompanying drawings, on which

Figure 1 shows an example of the way in which dimensions of a product were specified in the prior art,

Figure 2 shows a curve-template appertaining to a template system according to the present invention,

Figure 3 shows an example of how dimensions are specified using a template system according to the present invention, and

Figure 4 shows another example of how the dimensions of a product are specified according to the present invention.

A product 1, which is shown in Figure 1, has an external contour with a curve 2, and the way in which the dimensions are specified on a drawing of the said product 1 is shown as an example in Figure 1, with the actual dimensions indicated as letters. Figure 2 shows an example of a template 3 which appertains to a template system according to the present invention; this template system contains a plurality of differently-shaped templates. Each of the templates 3 in the said system expediently has a symbol 4, which in the present case consists of a circled letter A , which identifies and locates each of the templates 3 in the system. Preferably, the respective templates 3 have a congruent front and rear side edge surface 3A and 3B respectively, each of which has the shape of its template curve, making it possible to apply the respective templates 3 freely to an outwards-facing or inwards-facing congruent curve 2. Along the template 3 there is a location indicating calibration 5, which is preferably graduated in millimetres, and which is designed to be used for de fining the extent of a curve 2 over the actual template 3 which fits it, between a plurality of locationally-fixed points A1, A2, etc., on the template. Templates with straight and arc-shaped side edge surfaces can also be included in the template system according to the invention. Figure 3 shows an example of how dimensions are speci fied on a drawing with the aid of the present invention for a product 1 corresponding to that shown in Figure 1, where the curved surface 2' of the product 1' is designated "Template A", the template 3 with which the curved surface 2' corresponds and on which the locationally-fixed points A1, A2 lie between the marks 3 - 16 on the template calibration 5 on the template 3 with which the curve 2' corresponds.

Figure 4 shows another example of the application of the template system for snecifying the dimensions of another product 1² on a drawing. Due to the fact that the method proceeds expediently from a specific so-called fixed point A1², and different templates which display curve similarity and curve lengths corresponding to the respective curves over the product 1 ² are used, the actual product 1² can readily be defined. Starting from the fixed point A1² and moving in a clockwise direction on the drawing, the following templates and template curve lengths have expediently been used: Template K 1 - 2 between A1² and A2²,

Template T 3 - 12 between A2² and A3², Template K 1 - 4 between A3² and A4², Template F 2 - 6 between A4² and A5², Template D 7 - 21 between A5² and A6², Template K 1 - 3 between A6² and A7²,

Template U 6 - 12 between A7² and A8², Template K 1 - 6 between A8² and A9² and Template P 22 - 35 between A9² and A1²

By applying the template system throughout the entire design and production process a curve can readily be reproduced and re-applied at every stage of the process.

The system can also be used for digital shape control and shape determination. By making the memory of an NC machine aware of the template curve (by programming), the curve can be reproduced on the drawing, pattern, tool, etc. Naturally, straight lines and arc-shaped paths can also be registered in the same way by the machine.

When manufacturing products such as casting moulds and the like, for example, it was. frequently the practice in the past to proceed from the drawing stage via a prototype, ofte hand-made, which was later copied v/hen milling the casting mould. This process proved very costly, particularly when it was trhe intention to cast only a small series of the product.

The invention makes it possible, by applying the template system, to produce casting moulds without the need for the intermediate stage of producing a prototype.

According to the invention a forming tool for a hollow object with curved side surfaces, for example, which may als be double curves, is obtained in the following way: The drawing is prepared with the aid of a series of tem plates 3 equipped with calibrations 5 along their edges 3A, 3B, and having a curved, straight or arc-shaped path; an indication of which template and which section of its edge has been used is given on the drawing in the way which has already been described above.

Tool operators can expediently have a corresponding series of mould templates which fit in their forming milling machine, the mould template being inserted in the milling machine and the machine set so that it machines over the pointsA¹, A², etc. indicated on the drawing, on the calibration marks 5. In the event of a forming milling machine being used which is data controlled, for example, the values indicated on the drawing can be fed into its computer which thencontrols the movements of the milling machine. With this method of proceeding the costly prototype model can be dispensed with.

The invention is not limited to the embodiment which is described above and shown on the drawings merely by way of example, but it can be modified with regard to its details within the frame of the following Patent Claims.

Claims

P a t e n t C l a i m s

1. A process for manufacturing products ( 1;1¹;1²) such as casting moulds and patterns, for example, characterised in that the path of every single line (2; 2¹), such as curves which the contour of the product displays, for example, and which it is desired to depict and/or reproduce at any stage of the production process, is determined by means of a plurality of templates (3) appertaining to a template system, and that the similarity of the curve path to the template (3) which fits it is thereby determined, and that the length of the curve (2; 2¹) is defined over the said template which fits it, between a nlurality of specifically located points (A ¹; A², etc.), on the template

(3).

2. A process according to Patent Claim 1, characterised in that the said template system is applied throughout the entire product manufacturing process, from the drawing boar up to the machining process, and that an indication is give on the actual drawing as to which template (3) and which section of the template designates the actual extent of the curve (2; 2¹).

3. A process according to Patent Claim 2, characterised in that the extent of the curve (2; 2¹) is indicated on the basis of a location-marking calibration (5) on the associated template (3), which is preferably graduated in millimetres.

4. A process according to any of Patent Claims 1 - 3, characterised in that the actual template curve (3A; 3B) and its extent are programmed in the memory of an NC machine so that it is possible thereafter to reproduce it at sub sequent stages, for example, on a drawing, pattern and tool.

5. Apparatus for carrying out the process according to any of Patent Claims 1 - 4, characterised in that a template system contains a plurality of templates (3) with various curves, and along each of the curve paths (3A; 3B) on the respective templates (3) there are markings (5) of location, such as millimetre graduations over the template curve, for example.

6. Apparatus according to Patent Claim 5, characterised in that the template system contains templates (3) with arc shaped curvature, with asymmetric curvature and with a straight-line template contour.

7. Apparatus according to either of Patent Claims 5 - 6, characterised in that the respective templates (3) bave a symbol (4) which identifies and locates the template (3) in the said template system.

8. Apparatus according to any of Patent Claims 5 - 7, characterised in that the respective templates (3) have a congruent front and rear side edge surface (3A; 3B) which forms the said template curve.