Apparatus and method for fitting a flexible strip

Abstract: A robot hand is disclosed for fitting a length of channel-shaped sealing strip 8 to a flange 6 running around the door opening of a motor vehicle body. The sealing strip, with the sides of its channel initially splayed apart, is held coiled in a cassette 54. A take-up roller 32 is initially driven by a motor 30 to pull a length of the strip out of the cassette until its end F engages the flange, rollers 64,66 and 68 confining the strip to move in a curved path. Cradle 62 carrying these rollers is then moved clear of the path by piston-cylinder assemblies 60 and 80. The robot hand is then caused to travel around the door opening in the direction of the arrow G, motor 30 now rotating rollers 38 and 40 instead of roller 32. Rollers 38 and 40 press the sides of the channel of the sealing strip 8 into gripping engagement with the flange 6 and also drive the robot hand around the door opening.

Description: The invention relates to a robot arrangement for fitting a length of channel-shaped strip onto a mounting flange or the like, comprising mounting means, means on the mounting means for supporting the strip in a manner permitting it to be driven longitudinally, constraining means on the mounting means for constraining the strip to follow a predetermined curved path as it moves longitudinally so as to present the mouth of the channel facing outwardly of the curved path, the side walls of the channel of the strip being splayed apart when it is driven along the curved path and onto the flange, and strip-pressing means for pressing the splayed-apart side walls of the strip into gripping engagement with the sides of the flange. Such an arrangement is shown in DE-A-3 541 865. In this known arrangement, which describes the closest proir art, the constraining means comprises a plurality of pulleys which are mounted adjacent to each other on the outside of the curve of the curved path and which therefore ensure that the strip approaches the mounting flange in the correct direction. However, it is of course necessary for the robot arrangement to move along the flange as it lays the strip on the flange and presses the side walls of the strip into gripping contact with the flange. During this movement of the robot arrangement, the rollers of the constraining means move with and in front of it. If the mounting flange is, for example, a flange running around a door or other opening in a motor vehicle body, the flange will undergo sharp bends and will also run closely alongside other parts of the vehicle body. The presence of the rollers of the constraining means in front of the robot arrangement as it moves along the flange causes a problem because it impedes the manoeuvreability of the robot arrangement, making it difficult or impossible for it to follow sharp bends in the flange and these rollers may also tend to collide with adjacent parts of the vehicle bodywork. In addition, the strip pressing means of this known arrangement comprises a roller having two axially spaced discs which rotate with the roller and press on the side walls of the channel of the strip. Such an arrangement may not provide very effective pressing together of the splayed-apart side walls of the strip. The invention aims to overcome or mitigate these problems. FR-A-2 626 805 shows various arrangements of tools for use in fitting a channel-shaped strip onto a mounting flange or the like, where the side walls of the strip are initially splayed-apart. The tools provide two rollers rotatable about parallel axes spaced apart by such distance as to receive the splayed-apart side walls of the strip between them as it embraces the flange and to press them into gripping engagement with the sides of the flange. However, the tools described are hand tools, the strip being placed manually onto the flange. In accordance with the invention, the known robot arrangement is characterised in that the strip-pressing means comprises at least two drive rollers mounted on the mounting means adjacent the distal end of the curved path and rotatable about parallel axes spaced apart by such distance as to receive the splayed-apart side walls of the strip between them as it embraces the flange, motor means on the mounting means for driving the rollers in such predetermined rotary directions that they contact the splayed-apart side walls of the strip and press them into the said gripping engagement with the sides of the flange and also drive the mounting means along the flange drawing the strip longitudinally along the curved path and onto the flange, and by transporting means on the mounting means which is operable to move the constraining means clear of the curved path when the leading end of the strip at the distal end of the curved path has embraced the flange. Apparatus embodying the invention for fitting a sealing strip onto a motor vehicle door opening will now be described, by way of example only, with reference to the accompanying drawings in which: Figure 1 is a side view of the door opening showing the apparatus in block form only; Figure 2 is a cross-section of the sealing strip when finally fitted onto a flange surrounding the opening; Figures 3 and 4 are cross-sections of the sealing strip in the form which it has before it is fitted onto the flange, and when it is initially fitted onto the flange, respectively; Figure 5 is a perspective view of a robot hand forming part of the apparatus and in the state it assumes during an initial stage in the fitting process; Figure 6 corresponds to Figure 5 but shows the robot hand in a later state; Figure 7 corresponds to Figures 5 and 6 but shows a still later state; Figure 8 shows an enlarged perspective view of part of the robot hand to illustrate part of its mechanism in greater detail; Figure 9 shows the gear train within the robot hand; Figure 10 is a diagrammatic view of the robot hand but showing the gear train of Figure 9 in phantom form and with other parts omitted; Figure 11 shows the robot hand and illustrates it at another stage during the fitting process; Figure 12 illustrates a support assembly by means of which the robot hand can be attached to the robot arm; Figure 13 shows how the support assembly of Figure 12 is fitted to the robot hand; Figure 14 shows a side view of the support assembly of Figure 12 looking in the direction of the arrow XIV of Figure 12; and Figures 15 and 16 correspond to Figures 10 and 13 respectively but show a modified construction. Figure 1 shows the door opening 5 of a motor vehicle body. This door opening is defined by a flange 6 which runs around the door opening, lying generally in its plane, and which is formed where the inner and outer body panels come together, and are welded, at the door opening. In order to provide a seal for the door opening 5, the manufacture of the car body involves the fitting of a sealing strip (see Figures 2,3 and 4) onto the flange 6. Figure 2 shows a cross-section through the flange with the sealing strip 8 in position thereon. As shown, the sealing strip 8 comprises a channel-shaped gripping section 10 which, in use, embracingly grips the flange 6 and supports a soft tubular sealing section 12, so that the sealing strip runs around the door opening, with the sealing section 12 on the outside of the opening. When the door (not shown) closes onto the opening 5, it partially compresses the tubular sealing section 12 so as to form a weather-proof seal. The gripping section 10 is of channel-shape in cross-section and (in this case) is made of extruded rubber material 15 with an embedded channel-shaped metal carrier 16. The extruded material defines gripping lips 18 and 19 which frictionally grip the opposite facing sides of the flange and help to hold the gripping section firmly in position on the flange; lip 19 is directed oppositely to the other lips to provide improved sealing. As illustrated, the extruded material forming the gripping section 10 is integrally extruded with further extruded rubber forming the tubular sealing section 12. Instead, however, the gripping section 10 may be manufactured separately, and the tubular sealing section 12 attached to it afterwards, as by means of adhesive. In such a case, for example, the extruded material for the gripping section 10 may be plastics. The extruded material may be extruded so that different parts have different hardness. Thus, the lips 18 and 19 may be extruded from softer material than the remainder of the channel-shaped extruded material of the gripping section 10. This relative softness helps their sealing and gripping function. The extruded material of the tubular sealing section 12 may be of foamed or cellular construction to improve sealing efficiency. The metal carrier 16 may take any suitable form. For example, it may be made of continuous metal strip. Instead, however, it can be made of U-shaped links either connected together by short flexible connecting links or entirely separate. Another possibility is to construct the carrier from wire looped to and fro. Figure 3 shows the configuration of the sealing strip before it is fitted on the flange. It will be apparent that the sides of the channel of the gripping section 10 are splayed apart as compared with the configuration shown in Figure 2. This splayed apart configuration facilitates the assembly of the sealing strip 8 onto the flange 6 - as shown in Figure 4. After the sealing strip 8 has been fitted onto the flange 6 in the splayed-apart configuration shown in Figures 3 and 4, the splayed-apart sides of the channel are then pressed towards each other so that they assume the configuration shown in Figure 2, firmly gripping the sides of the flange and holding the sealing strip 8 securely in position on the flange. The apparatus and methods now to be described are concerned with the automatic fitting of the sealing strip 8 onto the flange 6, the fitting process involving the fitting of the seal 8 onto the flange in the splayed-apart configuration shown in Figures 3 and 4 and the subsequent step of forcing the channel walls of the gripping section towards each other to produce the result shown in Figure 2. The apparatus comprises several parts: a robot (not shown) having a robot arm (see Fig. 13) which carries a support assembly (illustrated in Figures 12 and 13), and a robot hand 20 which is fitted to the support assembly and will now be described in detail with reference to the various Figures of the drawings. Figure 1 illustrates the robot hand 20 in block form only and shows how it carries a cassette 22 (to be described in more detail below) containing a coil of the sealing strip 8 which is fed out of the cassette by the robot hand 20 which constrains it to follow a curved path and mounts it on the flange 6, whereafter the robot hand travels along the flange and rollers, to be described in detail below, force the splayed-apart sides of the gripping section towards each other. This process would normally be carried out before the door is fitted to the body. Figure 1 shows the robot hand 20 in two different positions and attitudes as it travels along the flange. Referring to Figure 5, the robot hand 20 comprises a body indicated generally at 24. The housing 24 has a casing 26, 28 containing a gear train to be described in more detail below by means of which a motor 30 (an electrical or pneumatic rotary motor for example) can drive various rollers. One of these rollers is a take-up roller 32 which is mounted adjacent a free-running roller 33. Motor 30 is connected to drive roller 32 through a planetary gear box and the gear train (to be described below) within the casings 26 and 28. In addition, the casing 28 supports drive rollers 38 and 40 which are rotatable about vertical axes and are driven by motor 30 via the planetary gear box 36 and the gear train within housings 26 and 28. Casing 28 also supports a free-running horizontally rotatable top roller 42. Also mounted on the housing 24 is a second motor 44. This motor, which may also be a rotary electrical or pneumatic motor, is connected through a gear box 46 for angularly moving a support arm 48 in the directions of the arrow A. Support arm 48 supports three claws 50 which engage a central boss in the cassette 22 which is shown dotted in Figure 5. Cassette 22 may take one of the forms disclosed in the published United Kingdom Patent Specification No. 2229702, though may take any other suitable form. Cassette 22 contains a coil of sealing strip 8, of the form shown in Figures 2,3 and 4, there being a predetermined length of such sealing strip within the cassette, this predetermined length matching the peripheral length of the flange 6 around the door opening 5. The housing 24 also supports a pneumatic piston-cylinder assembly 60 whose piston is oval in cross-section so that it cannot rotate. The piston-cylinder assembly 60 is connected to a cradle 62 which supports six contour rollers 63 to 68. Figure 8, which is a part view looking generally in the direction of the arrow VIII of Figure 5, and omits some of the contour rollers, illustrates the mechanism in greater detail. As will be seen, the cradle 62 is pivotally connected to a shaft 70 carried by a frame 72. The frame 72 comprises side members 74 and 76 which are interconnected by the shaft 70 and a rod 78. A pneumatic piston-cylinder assembly 80 contains a piston (not shown) having a piston rod 82 rotatably connected by a connection 84 to the upper end of the cradle 62. The piston-cylinder assembly 60 (see Figure 5), has a piston rod 88 connected to the side member 76. In a manner and for purposes to be described, the piston-cylinder assembly 60 moves the frame 72 to and fro in the direction of the arrows B, so as to carry the cradle 62 with it and its contour rollers, while the piston-cylinder assembly 80 pivots the cradle 62 about the axis of the shaft 70 in the directions of the arrows C. The operation of the robot hand as so far described will now be explained with particular reference to Figures 4,5 and 6. As already explained, the robot hand 20 is carried at the end of a robot arm (in the manner to be described in more detail below). The robot, which may be a six-axis robot, swings the robot hand 20 to a position where there is a stack of cassettes 22. The robot moves the swinging arm 48 into such position that the claws 50 engage the bore of one of the cassettes in the stack and picks up the cassette in the manner shown in Figure 5. The robot then swings the robot hand 20 into position over the flange 6 of the door opening 5, so that the rollers 38 and 40 are positioned on opposite sides of the flange as shown in Figure 5. It will be appreciated that this process is carried out during the normal assembly line manufacture of a motor vehicle body, and each body would automatically be brought to a predetermined position on the track adjacent to the robot. As shown in Figure 1, the robot hand is positioned between 80 and 90 angular degrees to the direction of the flange. A short length of sealing strip 8 protrudes from each cassette when picked up. The orientation of the sealing strip within the cassette 22 is such that the open mouth of the splayed-apart channel of the gripping section 10 (Figures 2,3 and 4) faces upwardly, as viewed in Figure 5. The first stage in the fitting process involves the movement of the cassette 22 generally to the right in the direction of the arrow D as shown in Figure 5. As shown in Figure 5, the claws 50 are mounted on a carrier 90 which is slidably mounted on the swinging arm 48 and is slid rightwards in the direction of the arrow D by a pneumatic or electric motor 91 mounted on the arm 48 and driving the carrier 90 through a rack and pinion arrangement 92. This rightward movement of the cassette moves the protruding end of the sealing strip 8 into the bight between the take-up roller 32 and the free-running roller 34 (Figure 5). In a manner to be described, motor 30 is then energised and rotates roller 32 in an anti-clockwise direction (as viewed in Figure 5) so as to pull the sealing strip 8 from the cassette 54. The emerging sealing strip passes over guides 93 and 94 and engages the contour rollers 63 to 68 in that order, these rollers constraining the the emerging sealing strip to follow the curved path shown in Figure 5, the strip passing further free-running guide rollers 96, 98, 96A and 98A. Distanced by a predetermined distance from its emerging initial end, the sealing strip 8 carries a sensible mark (for example, a white dot) which is sensed by a photocell arrangement (not visible) located near guide roller 93. Logic circuitry associated with the photocell stops the motor 30 (though permits its subsequent free running) when this dot is sensed, the dot being positioned so that the take-up roller 32 drives just sufficient length of emerging sealing strip as is necessary for its initial end to engage the flange 6 as shown at F in Figure 5. It will be observed that the open splayed-apart mouth of the sealing strip 8 is now engaging the flange 6. The piston-cylinder 80 (Figure 8) is now energised so as to pivot the cradle 62 in the direction C as shown in that Figure. Cradle 62 thus moves into the position shown in Figure 6, with the contour rollers now being moved clear of the sealing strip 8 and so that the cradle 62 is moved away from the flange 6. The contour rollers 63 to 68 are no longer required because the sealing strip 8 is constrained in its curved path (as illustrated dotted in Figure 5) by virtue of the fact that its end F is engaging the flange. The piston-cylinder assembly 60 is then energised so as to move the frame 72 (Fig. 8) to the right as viewed in that Figure. The cradle 62 thus now has the position shown in Figure 7 and is completely clear of the flange 6. Motor 30 is now caused (in the manner to be explained) to rotate the rollers 38 and 40 and at the same time the robot arm moves the robot hand 20 slightly along the flange as shown by the arrow G in Figure 6. This movement causes the initial end F of the sealing strip 8 to be laid down upon the flange 6 and to be embraced by the rollers 38 and 40. These rollers are positioned apart by a predetermined distance so that they press the splayed-apart sides of the gripping section 10 towards each other into the configuration shown in Figure 2. Because these rollers are driven by the motor 30, they continue to move the robot hand 20 to the right, in the direction of the arrow G, thus causing the sealing strip 8 to be continuously drawn out of the cassette 22 and laid upon the flange 6 with its gripping section 10 initially in splayed-apart configuration, the gripping section then being converted into the configuration shown in Figure 2 by the rotating rollers 38,42. During this process, the robot and the support assembly arm (not shown) cause the robot hand 20 to apply downward pressure onto the sealing strip 8 as it is being mounted on the flange 6, this pressure being applied through the medium of the free-running roller 42. The gripping section 10 is thus properly seated on the flange 6. In Figures 5,6, and 7, the sealing strip 8 is illustrated without the sealing section 12 (see Figures 2,3 and 4). However, this would of course be present and the roller 40 would apply side pressure to the corresponding splayed-apart side wall of the channel of the gripping section 10 via the sealing section 12. The free running roller 42 drives a tachometer 102 (see Figures 10 and 11) which thus produces an output dependent on its rotational speed which is a measure of the speed of movement of the robot hand 20 along the flange 6. A signal corresponding to this speed is fed to the control mechanism for the robot itself so that the robot can match the movement of its arm to the actual movement of the robot hand along the flange. The process continues until the full length of the sealing strip 8 has been laid on the flange. When the final end of the sealing strip passes over the photocell referred to above, it is sensed and causes the motor 30 to cease rotating the rollers 38 and 40 at a predetermined later instant which is such that the final end of the emerging sealing strip will have been laid on the flange. A corresponding signal is fed to the control for the robot itself so that the robot movement ceases. The robot then lifts the robot hand 20 clear of the body ready for a repeat of the process described on the next vehicle body arriving on the assembly track. The manner in which the motor 30 drives the take-up roller 32 and the drive rollers 38 and 40 will now be described with reference to Figures 9 and 10. Referring to Figure 9, motor 30 drives a shaft 110 via the gearbox 36. Shaft 110 is rigid with a gear 114 which rotates a gear 116 via intermediate gears 118 and 119. Gear 116 drives take-up roller 32 via a free wheel unit 120. As shown in diagrammatic form in Figure 9, the sealing strip 8 is positioned in the bight between the take-up roller and the free-running roller 34, Figure 9 showing the gripping section 10 and the sealing section 12 of the sealing strip. Shaft 110 is also rigid with a crown gear 122 engaging a second crown gear 124 driving a shaft 126. Shaft 126 drives the drive roller 38 and, through the intermediary of gears 128 and 130, the other drive roller 40. Figure 9 also shows the free-running top roller 42 and the tachometer 102 connected to it, although these are not part of the gear train being described. When motor 30 is first energised, it drives the take-up roller 32 in the anti-clockwise direction as viewed in Figure 5, and in this way drives the emerging initial end of the sealing strip 8 along the curved path towards the flange 6 in the manner described above. This rotation of motor 30 also causes rotation of the drive rollers 38 and 40. However, the latter rotation is of no effect because they are clear of the flange 6 and the sealing strip has not yet become positioned between them. In the manner already described, the photocell referred to above stops the motor 30 when the end F of the sealing strip has reached the flange 6 (Figure 5). Motor 30 is then reversed. Because of the free wheel unit 120, it no longer rotates the take-up roller 32, although the latter is now free to rotate as the sealing strip 8 is continued to be drawn from the cassette 22 by virtue of movement of the robot hand along the flange (in the manner described). The reversed movement of the motor 30 causes the rollers 38 and 40 to rotate in the correct rotary directions to drive the robot hand 20 in the direction of the arrow G (Figure 5). During the initial motion of motor 30, rollers 38 and 40 clearly rotate in the opposite directions to these "correct" directions; however, this is immaterial because rollers 38 and 40, being clear of the sealing strip at this time, have no effect. Figure 10 illustrates how the gears referred to in Figure 9 are arranged within the casings 26 and 28. As the robot hand 20 travels around the door opening, its orientation will have to change at each end or corner in the opening. At the points indicated at J,K,L,M and N in Figure 1 the robot hand is caused to turn angularly by an appropriate distance (90 degrees in the case of points J,K and N), turning about the sixth axis of the robot which is aligned with the centre of the radius of the particular bend or corner. As the robot hand travels around the door opening, it is also necessary to ensure that the cassette 22 does not interfere with the door opening itself or other adjacent body parts. In order to assist in this, motor 44 can be energised at appropriate points in the movement around the door opening to adjust the position of the cassette by turning the swing arm 48, as shown in Figures 1 and 11. In addition, the carrier 90 (Figure 5) can be slid in the direction D and in the reverse direction for the same purpose. Figure 12 shows the support assembly 150 which is fitted to the end of the robot arm 152 (Figure 13). The support assembly comprises a member 154 which is rigid with the arm 152 and can be angularly turned by the arm about an axis 156 (the robot's sixth axis). Member 154 is rigid with a first support plate 158 which is attached to a second support plate 160. The plates 158 and 160 are linked together by resilient shock absorbing means (not shown) which permits relative movement between the two plates in the directions indicated at P by plus and minus 12 millimetres. Plate 160 rigidly supports a vertical pillar 162 carrying the robot hand holder 164. The latter is slidable relative to the member 162 in the directions Q within a range of plus and minus 40 millimetres. Figure 13 shows how the support assembly 150 is actually attached to the robot hand itself. The limited ranges of movement in the directions P and Q permit some lattitude in the programming of the robot's movements and enable account to be taken of the inevitable tolerances in the dimensions of the vehicle body and its positioning on the assembly track. Thus, the robot could be programmed to move the robot hand in a series of straight lines, corresponding to the approximately straight lengths of the flange, with any deviations in the flange from actual straight lines being accommodated by the limited ranges of movement in the directions P and Q. Figure 14, which is a view looking in the direction of the arrow XIV of Figure 12 but with the support assembly 150 fitted to the robot hand 20, shows how the support assembly 150 may carry pointers 170,172 to indicate the amount of relative movement in the directions P,Q (Figure 12), as a programming aid. As the robot carries the robot hand around the door opening, it applies a substantially constant pressure to the outside of the base of the channel of the gripping section of the sealing strip 8 (via the top roller 42, see Fig. 5). Fitting of the sealing strip to the flange normally starts along the bottom of the door opening (between points J and K in Figure 1) and the exerted pressure is approximately 4 bar. This pressure is maintained as the robot hand travels around the door opening and the robot therefore has to take account of the changing effect of the weight of the robot hand itself. A constant thrust unit 166 (see Figure 12), acting between the member 162 and the robot hand support 164, helps to maintain this constant pressure. Figures 15 and 16 correspond to Figures 10 and 13 respectively and show a modification. The modification comprises the provision of an additional electric motor 180 which is connected to drive the roller 32 and the removal of the connections via gears 118 and 119 (see Figure 10) between motor 30 and roller 32. Thus, in the modified arrangement the drive to the rollers 38 and 40 on the one hand and the drive to the roller 32 on the other hand are completely separate and are derived from separately controllable motors 30 and 180 respectively. The operation is otherwise the same.

Claims: A robot arrangement for fitting a length of channel-shaped strip (8) onto a mounting flange (6) or the like, comprising mounting means (20), means (22) on the mounting means (20) for supporting the strip (8) in a manner permitting it to be driven longitudinally, constraining means (62 - 68) on the mounting means (20) for constraining the strip (8) to follow a predetermined curved path as it moves longitudinally so as to present the mouth of the channel facing outwardly of the curved path, the side walls of the channel of the strip (8) being splayed apart when it is driven along the curved path and onto the flange (6), and strip-pressing means (38,40,42) for pressing the splayed-apart side walls of the strip (8) into gripping engagement with the sides of the flange (6), characterised in that the strip-pressing means comprises at least two drive rollers (38,40) mounted on the mounting means (20) adjacent the distal end of the curved path and rotatable about parallel axes spaced apart by such distance as to receive the splayed-apart side walls of the strip (8) between them as it embraces the flange (6), motor means (30) on the mounting means (20) for driving the rollers (38,40) in such predetermined rotary directions that they contact the splayed-apart side walls of the strip (8) and press them into the said gripping engagement with the sides of the flange (6) and also drive the mounting means (20) along the flange (6) drawing the strip (8) longitudinally along the curved path and onto the flange (6), and by transporting means (60,72,80) on the mounting means (20) which is operable to move the constraining means (62 - 68) clear of the curved path when the leading end of the strip at the distal end of the curved path has embraced the flange. A robot arrangement according to claim 1, characterised in that the constraining means comprises a member (62) carrying at least one guide roller (63 - 68), the member (62) being mounted for pivotal movement on the mounting means (20) so as to pivot the guide roller (63 - 68) into and out of engagement with the strip (8) in the curved path and also mounted for translational movement in a direction transverse to the curved path. A robot arrangement according to claim 2, characterised in that the transporting means includes piston-cylinder means (60,80) connected to the member (62) for causing the said pivotal and translational movement thereof. A robot arrangement according to any preceding claim, characterised in that the strip (8) is initially stored in a coil thereof of predetermined length in a cassette (22) which is adapted to be supported by the mounting means (20) for dispensing therefrom. A robot arrangement according to claim 4, characterised by motor means (44) carried by the mounting means (20) for adjusting the position of the cassette (22) thereon. A robot arrangement according to claim 4, characterised in that the motor means (44,91) is capable of adjusting the position of the cassette (22) in two transverse directions. A robot arrangement according to any preceding claim, characterised by initial drive means (30,32) for engaging the leading end of the strip (8) protruding from the cassette (22) and for feeding the end into and along the curved path, and energisable to cause the leading end of the strip (8) to be fed to the distal end of the curved path. A robot arrangement according to claim 7, characterised by sensing means for sensing the passage of the strip (8) therepast and to control the initial drive means (30,32) to feed such length of the strip (8) as feeds the leading end of the strip (8) to the end of the curved path. A robot arrangement according to claim 7 or 8, characterised in that the initial drive means (30,32) comprises a take-up roller (32) driven by the motor means (30) which drives the drive rollers (38,40). A robot arrangement according to claim 9, characterised by free wheel means (120) interposed between the motor means (30) and the take-up roller (32), whereby the motor means (30) drives the take-up roller (32) through a predetermined amount of angular movement via the free wheel means (120) and simultaneously drives the drive rollers (38,40) in directions opposite to the said predetermined directions, the predetermined amount of angular movement being such as to feed the leading end of the strip (8) to the end of the curved path,; and in that, at the completion of the predetermined amount of angular movement, the motor means (30) drives the drive rollers (38,40) in the said predetermined directions and is prevented from driving the take-up roller (32) by the free wheel means (120), the free wheel means (120) permitting free-wheeling of the take-up roller (32) in response to subsequent passage of the strip (8) along the curved path. A robot arrangement according to claim 7 or 8, characterised in that the initial drive means includes a motor (180) which is additional to the motor means (30) driving the drive rollers (38,40). A robot arrangement according to any preceding claim, a further roller (42) mounted adjacent to the drive rollers (38,40) but rotatable about an axis transverse thereto so as to engage the strip (8) on the mounting flange (6) and to be driven by such engagement as the robot arrangement moves along the flange and lays the strip (8) thereon. A robot arrangement according to claim 12, characterised by speed measuring means (102) for measuring the speed of rotation of the further roller (42) and controlling the robot to move the robot arrangement along the mounting flange (6) at a corresponding speed. A robot arrangement according to claim 13, characterised by support means (150) interposed between the robot and the robot arrangement and permitting a predetermined degree of limited movement therebetween to accommodate programming tolerances and dimensional tolerances in the position of the mounting flange (6). A robot arrangement according to claim 14, characterised by indicating means (170,172) on the support means (150) for indicating the extent of such limited movement at any time.

Inventors: GOEDDERZ DIETER, GOEDDERZ, DIETER
Applicants: DRAFTEX IND LTD, DRAFTEX INDUSTRIES LIMITED
Application year: 1991
Main classification: B23P19
IPC codes: B62D65, B60J10, B23P19, B23P21