GB2289014A

GB2289014A - Device for trimming components

Info

Publication number: GB2289014A
Application number: GB9506899A
Authority: GB
Inventors: Alain Morice; Philippe Desclaux
Original assignee: Societe de Construction des Avions Hurel Dubois
Current assignee: Societe de Construction des Avions Hurel Dubois
Priority date: 1994-04-06
Filing date: 1995-04-04
Publication date: 1995-11-08
Anticipated expiration: 2015-04-04
Also published as: FR2718377B1; GB2289014B; FR2718377A1; GB9506899D0

Abstract

The invention relates to a device intended to equip a trimming machine including a motor driving a machining tool, the said machine operating by resting against a trimming template (5) fastened to a component (P), one edge of which has an excess length (25) to be removed, the said template guiding the movement of the said tool during the operation of removing the said excess length, the said device being intended to be fixed onto the end of the machine and being characterized in that it consists of a C-shaped component with two superimposed flanges (12, 13) which are rigidly joined together by one of their ends (14) and separated from one another by an open gap (15) on the opposite side to the connected ends of the flanges to allow the said excess length to engage between the said flanges, the said flanges (12, 13) having, on the open side of the gap, guide flanks (20, 21) which are designed to rest on the said trimming template (5) and having an orifice of axis (23) perpendicular to the said gap (15) passing through them in the vicinity of the guide flanks (20, 21), for the passage of the said machine tool. <IMAGE>

Description

The present invention relates to a device for trimming components.

Trimming machines, either portable ones or fixedstation ones, are known which are used to make the contours of a component comply with a fixed pattern, in other words to eliminate oversizing the edges of the component, in order to bring the component down to its final dimensions. Such machines are used for trimming metal components and, also, for trimming components made of composite materials.

In order to fulfil this trimming operation, a template is fastened onto the component to be trimmed, so that the template is set back relative to the desired cutting line. The trimming machine is equipped with a trimming head which includes a guide part and which has the cutting tool passing through it, and the guiding part of the trimming head, which projects relative to the tool, is rested against the trimming template, the tool then machining the contour of the component while the machine is guided by the template.

However, this known system has drawbacks which can lead to alteration or damage which is prejudicial to the component being processed.

Indeed, perfect perpendicularity of the tool relative to the edge of the component is difficult to obtain during operation, without multiplying the number of guides and items of holding equipment, which is neither economical nor, above all, possible in some circumstances. Moreover, in the case of components of complicated shape and which can be trimmed only using portable machines, achieving trimming depends on the manual dexterity of the user, which results in slowness and increased risk of damage, or in imperfections in the end product of the operation.

The object of the present invention is to make improvements to trimming devices which make any wrong move and any damage to the component impossible, while allowing use by unskilled labour, with an accuracy and speed of execution which are much greater than with the conventional devices.

This objective is achieved in 80 far as the invention provides a device intended to equip a trimming machine including a motor driving a machining tool, the said machine operating by resting against a trimming template fastened to a component, one edge of which has an excess length to be removed, the said template guiding the movement of the said tool during the operation of removing the said excess length, the said device being intended to be fixed onto the end of the machine and being characterized in that it consists of a C-shaped component with two superimposed flanges which are rigidly joined together by one of their ends and separated from one another by an open gap on the opposite side to the connected ends of the flanges to allow the said excess length to engage between the said flanges, the said flanges having, on the open side of the gap, guide flanks which are designed to rest on the said trimming template and having an orifice of ^ axis perpendicular to the said gap passing through them in the vicinity of the guide flanks, for the passage of the said machine tool.

Admittedly, a device forming a support and a guide for cutting elements of varying widths is known from US-A-4,768,570. However, this known device does not consist of a single C-shaped component, but of two independent flanges fastened together by screws and nuts.

The gap in this device consists of an intermediate component 30 which acts as a guide. This is therefore a very different device from the one which forms the subject of the present invention.

A device is also known, from US-A-2,925,017, which provides a guiding function, but this device is of extremely complicated structure and has no C-shaped component consisting of two flanges through which the trimming tool passes.

Preferably, the thickness of the gap of the device according to the invention is approximately 0.5 mm greater than the thickness of the component which is to be trimmed.

With the excess length of the component being held permgnently between the two flanges in the gap, one can be sure that the tool is operating perpendicularly to the edge of the component; furthermore, by virtue of the presence of the guiding flanks, the tool can be made to work on both sides of the component, while all the time being assured of correct positioning on the template: in fact, in one position of the machine, one of the flanks interacts with the guiding template while, in the inverted position of the machine, it is the other flank which fulfils this function.

The system according to the invention has quite a specific advantage in the case of portable manual trimming machines, but it applies equally well to fixedstation machines.

The means for fastening the device according to the invention onto the end of the trimming machine may consist of a mounting plate secured to, or integral with, one of the flanges and exhibiting a fastener which is designed to interact with a complementary member provided on the said machine. This embodiment will be suitable, for example, in the case where the machining tool is a rotary burr.

The abovementioned fastening means may assume varying forms depending on the type of machine adopted and depending on the configuration of the corresponding tool: cutting tool, diamond-encrusted burr, milling tool, nibbling tool, fluid jet cutting tool, laser cutting tool, etc.

The part of the flanges which is situated on the open side of the gap is advantageously in the form of a portion of a circle because that makes guiding relative to the trimming template easier and guarantees concentricity at all points in the path of the tool.

For preference, the gap, on the opposite side to its open side, has a widened chamber making it easier for the said guide flanks to move over the templates of components being formed. To the same end, it is also advantageous to chamfer the lateral sides of the flanges, along the entire length of the gap.

The flange situated on the machine side may be thicker than the opposite flange so as to take a thick trimming template, for sample an already-existing template, the thickness of the opposite flange being sufficient to bear correctly against the template.

Other features and advantages of the invention will emerge from the following description given with reference to the appended drawings in which: - Figure 1 illustrates a trimming machine of the prior art, in two positions relative to the trimming template, - Figure 2 represents the device according to the invention, in a first embodiment, mounted on the end of the body of a trimming machine, - Figure 2a is a section on a-a of Figure 2, - Figure 2b is a view in the direction of the arrow B of Figure 2, - Figure 3 is a side view, in more detail, of the device of Figure 2, - Figure 4 is a plan view of the device of Figure 2, - Figure 5 is an end-on view of the device of Figure 2, - Figure 6 is a side view of a second embodiment of the invention, and - Figure 7 is a plan view of the device of Figure 6.

In order to make it easier to understand the nature and advantages of the device according to the invention, the operating principle of a manual trimming machine according to the prior art will first be described, which machine, in Figure 1, is represented in two different positions, respectively at the two ends of a guiding template.

More precisely, the body 1 of the machine, which can be held in the hand, contains a motor. At the end of the body 1 there is fitted a trimming head 2 from which a tool 3 extends which, in the example represented, is a rotary burr. The trimming head 2 includes a feeler 4 which is intended to slide along the edge 6 of a trimming template 5 fastened to a component P to be trimmed.

As can be seen in Figure 1, in the case of a complicated component P (here a Z-shaped component), it is impossible or very difficult to trim the end A of the component because the trimming head 2 will run into the template 5 in the position represented in the top part of the figure.

In such a case, the only solution is to invert the machine, but the tool 3 is then no longer guided on the template 5 and the edge of the component P cannot be trimmed conveniently.

As Figure 2 shows, in particular, the device according to the invention makes it possible to overcome this difficulty because inverting the machine (position in broken line, to the right in the figure) makes it possible to have guidance which is just as effective as in the other position of the machine (position in solid line, to the left of the figure).

The first embodiment of the invention will now be described in more detail with reference to Figures 2 to 5.

In order to simplify the explanation, it will be assumed that the device according to the invention equips a portable trimming machine of the same type as that of Figure 1, of which part of the body 1 can be seen, and which will not be described again. The components common to Figure 1 and to Figures 2 to 5 are identified by the same references.

The device according to the invention includes a member 10 for fastening or coupling at the end of the machine (for example a screw thread, as represented).

The member 10 is secured to a mounting plate 11 of elongate shape and which bears against the front face of the machine so as to be immobilized thereon.

Under the mounting plate 11, and secured to it, there are two elongate flanges 12 and 13 joined together by their end 14, these two flanges being superimposed and separated from one another by a gap 15 so as to form an elongate C, when viewed from the side. The front face, or front flank, of the device, that is to say the opposite side to the connected ends 14 of the flanges, is open and this opening gives access 16 to the gap 15. The device is also open, at 17 and 18, along the lateral edges of the flanges (Figure 5). The openings 17 and 18 of the gap 15 are preferably chamfered. The gap 15 advantageously has a widened chamber 19, set away from the frontal access 16.

The flanks 20 and 21 of the ends of the flanges 12 and 13 have a rounded profile in the shape of a portion of a circle.

The assembly formed by the coupling member 10, the mounting plate 11 and the two flanges 12 and 13 has an orifice 22 (see Figures 3 to 5) passing through it, whose axis 23 is perpendicular to the plane of the gap 15. This orifice 22, which emerges on both sides of the assembly, allows the trimming tool 3 to pass through, which trimming tool, in the case represented, is a rotary burr.

As can be seen in Figure 3, the generatrix of the tool 3 is set back relative to the front flanks 20 and 21 of the flanges. It will be noted that the upper flange 12 is thicker than the lower flange 13.

It will be understood that, in order to trim the component P of Figure 2, the gap 15 is engaged, via its access 16, over the edge of the component P until the flank 20 of the flange 12 comes into contact with the trimming template 5.

With the edge 25 of the component P held in the gap 15, it can be understood that the perpendicularity of the trimming tool 3 is perfect and that the cut edge of the component P will be perfectly straight.

In Figure 2, the excess length of the component P to be removed is denoted by L, and the desired cutting line is denoted by x-x'. It can be seen that the template 5 is set back relative to this cutting line x-x'.

It is sufficient (position in solid line, to the left in Figure 2) to slip the flank 20 of the upper flange 12 of the device according to the invention along the template 5 in order to achieve trimming, it being possible for the chopped-off material to be removed into the chamber 19 of the C-shaped component.

When one wishes to operate on the right-hand edge of the component P, the machine is inverted (position in broken line, to the right of Figure 2): it is then the flank 21 of the lower flange 13 which comes into contact with the trimming template 5, giving perfect guidance.

Any wrong move is thus eliminated.

Figures 6 and 7 represent an alternative to the embodiment of the device according to the invention which is designed for a tool known as a "stage screw". This is a cutting tool in the form of a helix or spiral, driven in rotation and shearing the component to be trimmed (right-hand thread).

In these Figures 6 and 7, the same references as before have been used when denoting the same components, and the same references followed by the prime sign have been used when denoting similar components.

The diameters of the tool 3' and of the orifice in the trimming head 2' are adjusted to give good shearing of the component to be trimmed. The means 11 for coupling the device according to the invention is integral with the trimming head 2'. Instead of being integral therewith, the two components 11' and 2 could be separate, but securely attached.

In the annexed claims reference numbers have been used purely by way of aiding comprehension but such use is not intended to have any scope-limiting effect whatsoever.

Claims

1. Device intended to equip a trimming machine including a motor driving a machining tool (3; 3'), the said machine operating by resting against a trimming template (5) fastened to a component (P), one edge of which has an excess length (25) to be removed, the said template guiding the movement of the said tool (3; 3') during the operation of removing the said excess length, the said device being intended to be fixed onto the end of the machine and being characterized in that it consists of a C-shaped component with two superimposed flanges (12, 13; 12', 13) which are rigidly joined together by one of their ends (14) end separated from one another by an open gap (15) on the opposite side to the connected ends of the flanges to allow the said excess length to engage between the said flanges, the said flanges (12, 13; 12', 13) having, on the open side of the gap, guide flanks (20, 21) which are designed to rest on the said trimming template (5) and having an orifice (22) of axis (23) perpendicular to the said gap (15) passing through them in the vicinity of the guide flanks (20, 21), for the passage of the said machine tool (3; 3').

2. Device according to Claim 1, characterized in that the part of the flanges (12, 13; 12', 13) which is situated on the open side of the gap (15) is in the form of a portion of a circle.

3. Device according to Claim 1 or 2, characterized in that the gap (15), on the opposite side to its open side, has a widened chamber (19) making it easier for the said guide flanks (20, 21) to move over the templates of components (P) being formed.

4. Device according to any one of the preceding claims, characterized in that the flange (12; 12') situated on the machine side is thicker than the opposite flange (13).

5. Device according to any one of the preceding claims, characterized in that the gap (15) furthermore emerges laterally (17, 18) on the lateral side of the flanges.

6. Device according to any one of the preceding claims, characterised in that the thickness of the gap (15) is approximately 0.5 mm greater than the thickness of the component (P) which is to be trimmed.

7. Device intended to equip a trimming machine including a motor driving a machining tool (3; 3'), the said machine operating by. resting against a trimming template (5) fastened to a component (P), one edge of which has an excess length (25) to be removed, the said template guiding the movement of the said tool (3; 3') during the operation of removing the said excess length, the said device being intended to be fixed onto the end of the machine and being characterised in that it consists of a C-shaped component with two superimposed flanges (12, 13; 12', 13) which are rigidly joined together by one of their ends (14) and separated from one another by an open gap (15) on the opposite side to the connected ends of the flanges to allow the said excess length to engage between the said flanges.

8. A device according to claim 1 or claim 7 subsequently as herein described with reference to and as shown in Figures 1 to 5 or Figures 6 and 7 of the accompanying drawings.