GB2281395A - Apparatus for use in manufacture and inspection - Google Patents

Abstract

A modular system for use in manufacture and/or inspection of three-dimensional components such as pipework assemblies comprises, mounted a generally planar base (1), a plurality of first supports (10, 20). Each first support (10, 20) carries, via a second support (30,40) set on the first support, third support units which engage directly with part of the component being made or inspected. The third support units can include jigs or other fixtures for, e.g., positioning clips, end pieces or T-pieces. The connections between the support units may be adjusted to vary the position and orientation of the third support units to enable them to be located as desired. <IMAGE>

Description

APPARATUS FOR USE IN NANUFACTURE AND m INSPECTION This invention relates to apparatus for use in manufacture and inspection to assist correct threedimensional positioning.

There are many instances in the manufacture of articles where the shape and configuration of the article are of major importance, and deviations from the desired shape or configuration can have adverse consequences. Shape and configuration can be imparted with relative ease in many manufacturing processes - moulding, casting, turning, for example - and in such cases it is relatively easy to check that the item as made is in fact of the desired dimensions and shape, or at least lies within the permissible tolerances for the item in question.

There are, however, other areas which do not lend themselves either to simple accurate manufacture or checking. One example is the production of specialised components for engineering assemblies, e.g. pipework assemblies for use, as part of an aircraft engine or air frame, automotive lubrication systems and various military and radar applications. These components are complex in shape and may have a number of other attachments such as end fittings and fixing clips, which need to be accurately made and fitted to form a subassembly which can subsequently be worked into position and secured.

In the past, such items were generally produced first by hand, with the finished item being used as a master or model for the subsequent manufacture of a jig or fixture, usually made of wood or metal, and which then defines the physical shape and size of the item. This jig or fixture could subsequently be used as a pattern against which to form or align further sub-assemblies in volume production. Such an approach is expensive and time consuming, and in any event relies on a master "original part" being first made. Nowadays, CAD systems are widely used, and these do not produce a "master part in physical form, only a set of data which define that part spacially.

We have now found that manufacture and inspection of such items can be considerably facilitated by the use of a modular structural system which can be built up from a base using standard components to provide a temporary pattern or jig which, after use, can be disassembled and then rebuilt for future use with a different item.

According to the present invention, there is provided apparatus for use in defining a plurality of loci in three dimensions to facilitate manufacture or inspection of a three-dimensional article, the apparatus comprising a generally planar base an array of engagement means on the base a plurality of first support units each having means to engage the engagement means on the base at a desired fixed position, and a connector movable with respect to the engagement means in a direction substantially normal to the plane of the base to vary the distance of the connector from the base a plurality of elongate second support units engageable with the connectors of the first support units in a fashion that the end of each second support unit may be variably spaced from the connectors, and a plurality of third support units each engageable directly or indirectly with a second support unit at a position distant from its engagement with one of the first support units and each having a locus-defining surface at a position remote from its engagement with the second support unit.

Preferably the connector of the first support unit can be rotated about the axis normal to the plane of the base and means are provided to fix the connector in a given rotational position.

Using apparatus of this type it is particularly straightforward either to make or inspect components where a physical master component exists or in cases where the component is defined only by a set of dimensional data. In the latter case, it is convenient to provide that the planar base is accurately flat and can cooperate with distance measuring means enabling the locus-defining surfaces of the third support units to be set above the (generally horizontal) base plate in the desired positions.

Each position can thus be defined by a series of support units built up in sequence from the base, the final support unit being, e.g. specialised depending on the precise purpose for which the particular position is defined. For example, in the case of a pipe for an aeroengine, some of the support units most remote from the base will be end fixture holders and some of them will be clip holders which may be used to hold clips in position while they are attached to a piece of pipe, e.g. by brazing, welding or adhesion. Other specialised third support units may be envisaged, for example, a jig for holding three pipe ends to be united with a T-piece.

The base and support units are preferably of metal. The base preferably has a regularly spaced array of fixing apertures on it, e.g. threaded holes, enabling the first support units to be simply bolted on at suitable positions. Second and third support units can then be added in sequence until the desired position is achieved, i.e. the position-defining surface on the third unit is where it is meant to be. Both first and third support units are thus preferably constructed in two parts movable with at least one (and preferably more) degree of freedom one relative to the other, and wherein each is provided with fixing or locking means to enable the two parts to be fixed spacially relative to one another, enabling the final locus-defining surface on each third support to be located where desired, both as regards position and orientation, relative to the base.As will appear below, the second support units may be single part units.

As noted above, the third support units may be directly or indirectly engageable on the second support units.

While for reasons of rigidity it is preferred not to have too many units in series, it is within the scope of the invention to provide more than three support units in series on the base where convenient.

It should be noted that the manufacture of each of the supports does not require high precision manufacture with tight dimensional tolerances. Rather, the supports merely need to be made adequately robustly, especially in cases where four are in series, counting from the base, and with good flexibility of positional adjustment between their component parts. Fixing or locking means can be conventional, for example clamping screws or nuts to fix a pin in a sleeve at a desired axial and rotational position.

The invention is described, by way of example, with reference to an embodiment shown diagrammatically in the accompanying drawings, in which Figure 1 is a diagrammatic perspective view of parts of apparatus according to the present invention, Figures 2, 3 and 4 are diagrammatic views of various third support embodiments; Figure 5 is a view of a clipholder; Figure 6 is a diagrammatic view of an alternative headpiece to that shown in Figure 2, which has the facility to accept various attachments, e.g. plungers and face plate; Figure 7 is a face plate attachment for use with the headpiece of Figure 6; Figure 8 is a diagrammatic view of a simplified tee setting piece which can be used as an alternative to that shown in Figure 3;; Figure 9 is a view of a profiled clip station which is used in conjunction with a clamping tag setting piece shown in Figure 5 and which is to fit on the third support shown in Figure 2, and Figure 10 is a photograph showing apparatus according to the invention in use.

Referring to Figure 1, this shows a corner of a base plate 1 having on it an array of threaded holes 2 regularly spaced at a suitable pitch, for example 20 mm.

Only one corner is shown as the overall size of base plate will vary with the job in hand. Also, although the base plate is drawn as if resting on a horizontal surface, there is no objection in principle to the plane of the base plate being inclined to the horizontal or even vertically mounted, and this may be desirable in certain manufacturing situations.

Screwed into the base plate 1 are two first supports 10, 20. Each consists of a cylindrical base part 11, 21 bearing a threaded stud or a threaded bore on or in its lower part allowing it to be screwed into plate 1 or on to a threaded stud previously loosely screwed into plate 1. Base parts 11, 21 have a central bore into which fits a shaft 12, 22 bearing at its upper end as drawn a transverse sleeve 13, 23. The shaft can slide vertically in the base part and can rotate about its axis. A transverse lock screw 14, 24 is set in a threaded bore transverse to the central bore in base part 11, 21 enabling sleeves 13, 23 to be fixed at a desired height above plate 1 and at a desired angle with respect to its edges.

Each first support unit 10, 20 carries a second support unit 30, 40 respectively consisting of a shaft 31, 41 adapted to fit into sleeve 13, 23 respectively and to be held at a desired axial position and angular orientation by means of a transverse lockscrew 15, 25 respectively set in a threaded bore in the wall of sleeve 13, 23. The end of each second support unit 30, 40 carries a transverse sleeve 32, 42, the wall of which has a similar threaded lockscrew 33, 43 set in it.

Sleeves 32, 42 are for the reception of a third support unit or they can also receive a further second support unit which, in turn, can then receive a third support unit. Clearly, it is convenient for the internal diameters of sleeves 13, 23, 32 and 42 and the bore in base parts 11, 21 all to be identical, and for the diameters of shafts 12, 22, 31 and 41 likewise identical, to maintain overall versatility of the apparatus.

Figures 2 to 4 show various units which each have a mounting post 50 which fits into sleeve 32, 42 and can be fixed therein using lockscrew 33, 43 respectively.

Figure 2 shows a unit with a ball and socket joint between post 50 and a mounting block 52. The block 52 can be locked into position by a lever 53 operating in known fashion. Set on block 52 in one of the T-groove standard mounts is a suitably positioned angle plate 55 for defining a tube location, the tube being part of the subassembly it is desired to manufacture. In this and subsequent figures, the piece being made (or checked) is denoted 60.

Figure 3 shows a tee setting jig with setscrews 65 for fixing the tube 60 relative thereto and an angled surface 66 for locating a T-piece setting station.

Figure 4 shows a V-groove support station complete with clamp which is used at the initial setting stage and on pipework containing short straights.

Figure 5 shows how, during manufacture, certain parts may be set on to tube 60 which is supported elsewhere along its length by some third supports. As shown in Figure 5 a clamping tag setting piece 70 is held by a calliper clip 72 against the pipe 60, tightened in place by a hand-nut 74. The correct position of tag setting piece 70 can be easily determined using suitable measuring methods such as a co-ordinate measuring machine or conventional measuring techniques working from the base 1, such as height gauge, sine bar or dial gauge.

Referring to Figure 6, this shows an alternative headpiece to that shown in figure 2. A central block 80 is seated on the ball (of the ball and socket joint) and can be tightened in position by a lever 82. A shaft 84 slides through the central block 80 in the direction of arrow 85 and can be clamped against axial movement by means not shown. One end of shaft 84 has an end alignment piece including a spigot 87 which fits in the end of a pipe unit, and a shoulder 88 which abuts the end of the pipe, and which alignment piece is held in place by a threaded shaft which can be turned by a lever 86.

If the end of the pipe unit is to have a flanged fitting mounted to it, the end alignment piece may be removed by turning lever 86 anti-clockwise until it becomes released. A faceplate shown in Figure 7 with a threaded hole 89 in its centre can then be threaded on to the shaft and tightened up against the end of shaft 84.

The alignment spigot 81, working in conjunction with the alignment guide 83, which is fixed to shaft 84, prevents shaft 84 rotating, which ensures alignment through the full travel of shaft 84 in block 80, when the face plate of Figure 7 is attached and needs to be moved to and fro (but without rotation) between successive assembly operations.

Figure 8 shows a simple form of T setting piece. The pipe may be clamped between a screw clamp 90 and a v-groove 91. The U-shaped body 92 carries an angled surface 93 analogous to surface 66 in Figure 3.

Figure 9 shows a clip setting piece. It has a fixing hole 94 for the receipt of a bolt holding it on to one of the T-section grooves of block 52, and a profiled groove 95 of shape complementary to the clip to be attached to the pipe. The fixing hole for the clip has its position defined by a location pin 96 which can be threaded into a tapped hole 97, and unscrewed therefrom to assist removal of the pipe assembly after the clip has been fixed to the pipe.

Claims (6)

1. Apparatus for use in defining a plurality of loci in three dimensions to facilitate manufacture or inspection of a three-dimensional article, the apparatus comprising a generally planar base an array of engagement means on the base a plurality of first support units each having means to engage the engagement means on the base at a desired fixed position, and a connector movable with respect to the engagement means in a direction substantially normal to the plane of the base to vary the distance of the connector from the base a plurality of elongate second support units engageable with the connectors of the first support units in a fashion that the end of each second support unit may be variably spaced from the connectors, and a plurality of third support units each engageable directly or indirectly with a second support unit at a position distant from its engagement with one of the first support units and each having a locus-defining surface at a position remote from its engagement with the second support unit.

2. Apparatus according to Claim 1, wherein the connector of the first support unit can be rotated about the axis normal to the plane of the base and means are provided to fix the connector in a given rotational position.

3. Apparatus according to Claim 1 or 2, wherein some of the third support units include a ball and socket joint and means for locking and releasing movement between the ball and socket of the joint.

4. Apparatus according to any one of Claims 1 to 3, wherein each support unit includes clamping means to enable it to be fixed at a desired position with respect to an adjacent support unit connected thereto.

5. Modular apparatus substantially as hereinbefore described with reference to Figures 1 to 9 of the accompanying drawings.

6. Modular apparatus substantially as shown in the accompanying photograph.