GB2185206A

GB2185206A - Hand tools

Info

Publication number: GB2185206A
Application number: GB08600857A
Authority: GB
Inventors: William Retford
Original assignee: BULLDOG TOOLS; Bulldog Tools Ltd
Current assignee: BULLDOG TOOLS; Bulldog Tools Ltd
Priority date: 1986-01-15
Filing date: 1986-01-15
Publication date: 1987-07-15
Anticipated expiration: 2006-01-15
Also published as: GB8600857D0; GB2185206B

Abstract

A hand tool such as a fork is produced by first forming a blank 10 using a profile cutting technique, particularly a burning technique eg. oxy-fuel, plasma or laser. This produces a dramatic reduction in scrap. Preferably a plurality of blanks are cut out, and components of the tools, e.g. fork tines 15, are interdigitated to further reduce scrap. A still greater reduction in scrap can be achieved by cutting out the tines in an initial position in which they lie closer together than they will in the finished product. They can subsequently be deformed into their final position during a finishing operation. <IMAGE>

Description

SPECIFICATION Hand tools The invention relates to hand tools and particularly to hand tools such as garden forks and spades.

Forks and spades can be made using castings or by fabrication from sheet steel with indents pressed in to stiffen them but such products are significantly inferior in quality to those which are produced in one piece from thick section bar or plate.

The present method of manufacture in one piece from thick section bar or plate involves the use of forging. Blanks of appropriate shape are blanked out of bar or plate and then the working parts of the tool, for example the tines of a fork, are forged individually to the correct length and cross-section.

With a fork, an operation known as prong rolling is used to produce the tines. Each prong is rolled in turn, the other prongs initially being bent out of the way to facilitate access to the prong being rolled. Once all the prongs have been individually rolled, they are then bent back into the appropriate position.

A high degree of skill is required to roll each prong to produce the desired cross-section, and considerable effort is required to temporarily bend the other prongs out of the way.

As forks may have, for example, eight, ten, twelve or fourteen tines, the work can be complex and a considerable level of concentration is needed which must be maintained over long periods.

With this method of manufacture, the scrap material content, i.e. the difference between the weight of the original blank, and the weight of the finished tool, varies from about 40% for a four prong border fork to 24% for an eight prong tarmac fork.

If attempts are made to reduce the amount of skilled labour required, for example by producing blanks to virtually the finished size, far more scrap material is produced. For example with a four prong border fork the weight of scrap might be 159% of the weight of the finished tool.

We have now developed an alternative method of producing such tools which reduces the amount of skilled labour required, but still makes it possible to keep scrap quantities to a reasonable level.

Accordingly, the invention provides a method of producing hand tools such as spades or forks, comprising forming a blank using a profile cutting technique.

The profile cutting may be carried out using a burning technique, for example using oxyfuel burning, plasma burning or lazer burning.

Preferably a plurality of blanks are cut out, the blanks being arranged close together in a pattern which reduces the amount of scrap material.

Preferably components of one blank, for example the tines of a fork, are inter-digitated with the components of another blank, to further reduce the amount of scrap.

Since the said components, for example the tines of a fork, may, in the finished product, be spaced apart by a distance which is greater than the thickness of the components, even inter-digitation can leave significant scrap. To further reduce scrap, it is therefore preferred that the said components are initially cut out in a position in which they lie closer together than they will in the finished product, and are subsequently deformed into their finished position.

By way of example, specific embodiments of the invention will now be described, with reference to the accompanying drawings, in which: Figure 1 is a plan view of blanks for use in the manufacture of a first embodiment of garden fork according to the invention, the prongs of the blanks being inter-digitated; Figure 2 is a similar view illustrating a second embodiment in which fork tines are not only inter-digitated but also deformed to reduce further the amount of scrap; Figures 3 and 4 are views similar to Fig. 2 but showing third and fourth embodiments in which different deformation methods are used; Figure 5 illustrates yet another embodiment in which yet another deformation method is used; and Figures 6 and 7 il!ustrate sixth and seventh embodiments in which deformation is used without inter-digitation.

Fig. 1 illustrates one complete fork blank 10 and two further blanks 11 and 12 which are only shown partially for the sake of simplicity.

The blanks are in fact identical in shape and each comprise a shank portion 13, a cross member 14, and tines 15.

After the blanks have been cut out to the shape shown, the shank portion 13 is formed into a socket to receive the shank of the fork and the tines 15 are finished off to their final dimensions. Since however the blanks are cut out using an accurate profile cutting technique, the tines have substantially the final shape of the finished product and only minimal further treatment is required, thus reducing the amount of skilled labour required.

In order to reduce scrap metal, the tines of the blanks 11 and 12 are inter-digitated with the tines of the blank 10 as shown. Since however the spaces between the tines are substantially greater than the thickness of the tines, there is still a considerable amount of scrap material, for example as shown at 16.

Even in the centre of the blank 10, where edge tines of the blanks 12 and 13 are both fitted into a single space between two of the tines of the blank 10, there is still a certain amount of scrap 17.

Fig. 2 shows an alternative embodiment util ising two identical blanks 18 and 19. However the cross pieces 14 are angled with respect to the shank portions 13, and the tines 15 are angled with respect to the cross portions 14. This has the effect of reducing the spaces between the tines 15 so that when the tines of the two blanks are inter-digitated, there is very little scrap material left.

Fig. 3 illustrates yet another embodiment which is somewhat similar to Fig. 2 but the two halves of each cross piece 14 are both angled away from the associated shank portion 13.

Fig. 4 illustrates yet another embodiment generally similar to Fig. 3, except that the two halves of each cross piece 14 are angled towards the associated shank portion 13.

Fig. 5 illustrates yet another embodiment in which the tines 15 are divided into two sections and the two sections are arranged to project parallel to one another away from the central shank portion 13.

Fig. 6 illustrates yet another embodiment in which the cross piece 14 is curved and the tines 15 initially project towards one another from the curved cross piece 14 and then extend parallel to one another in very close relationship. In this embodiment tines are not inter-digitated but other similar blanks can be positioned closely adjacent to the blank shown.

Finally, Fig. 7 illustrates an embodiment which is generally similar to Fig. 6 in principle except that there are fewer tines and the root portions of the two outermost tines may eventually be deformed to form part of the cross piece 14, the ends 20 of the central tines being cropped off after deformation of the outer tines so that all the tines eventually end up the same length.

The invention is not restricted to the details of the foregoing embodiment.

or laser burning.

Claims

1. A method of producing hand tools such as spades or forks, comprising a blank using a profile cutting technique.

2. A method as claimed in claim 1, in which the profile cutting is carried out using a burning technique.

3. A method as claimed in claim 2, in which the burning technique comprises oxyfuel burning, plasma burning or laser burning.

4. A method as claimed in any one of the preceding claims, in which a plurality of blanks are cut out, the blanks being arranged close together in a pattern which reduces the amount of scrap material.

5. A method as claimed in claim 4, in which components of one blank are inter-digi tated with the components of another blank, to reduce the amount of scrap.

6. A method as claimed in any one of the preceding claims, in which the components of at least one blank are initially cut out in a position in which they lie closer together than they will in the finished product, and are subsequently deformed into their finished position.

7. A method as claimed in claim 5 or claim 6, in which the said components comprise the tines of a fork.

8. A method as claimed in claim 7, in which a blank comprises a shank portion, a cross member and a plurality of tines projecting from the cross member, the tines initially being cut out such that they project from the cross member at an inclined angle.

9. A method as claimed in claim 8, in which the cross member is initially cut out such that the cross member has two arms arranged at an inclined angle to each other.

10. A method as claimed in claim 9, in which the two arms initially project away from the shank portion.

11. A method as claimed in claim 9, in which the two arms initially lie closely adjacent to the shank member.

12. A method as claimed in claim 7, in which the tines are initially cut out such that at least one tine projects from one side of a shank portion and at least one other tine projects in the opposite direction.

13. A method as claimed in claim 7, in which the tines are cut out such that they have respective first portions which project from a cross member in a converging manner and have respective second portions which project in a parallel manner.

14. A method of producing hand tools, substantially as herein described, with reference to the accompanying drawings.

15. A hand tool constructed and arranged substantially as herein described, with reference to Fig. 1, or Fig. 2, or Fig. 4, or Fig. 5, or Fig. 6, or Fig. 7 of the accompanying drawings.