US2476038A

US2476038A - Machine used for the assembly of large-sized metal panels

Info

Publication number: US2476038A
Application number: US626059A
Authority: US
Inventors: Golbert Serge
Original assignee: Societe Nationale des Constructions Aeronautiques du Sud Est SNCASE
Current assignee: Societe Nationale des Constructions Aeronautiques du Sud Est SNCASE
Priority date: 1945-06-06
Filing date: 1945-11-01
Publication date: 1949-07-12
Anticipated expiration: 1966-07-12

Description

July 12, 1949. GQLBERT 2,476,038

MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet l Pia-1.

fiwenzor 55x GoLBERT fitter-hey:

July 12, 1949. s. GOLBERT 2,476,038

MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 2 [m enzor I SERGE 60L BERT Attorney:

July 12, 1949.

Filed NOV. 1, 1945 9 Sheets-Sheet 5 fltwmay y 1949- s. GOLBERT 2,476,938

. MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 4 fmre/vzar Serge Go/ber-f Byidmm du 89 July 12, 1949. s. GOLBERT 2,476,038

MACHINE USED FOR THE ASSEMBLY 0? LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 5 Inventor Atorney:

July 12, 1949. s. GOLBERT 2,476,038

MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 6 FiGJQ. fiiaw FEM-- JJE'RGE 60455,??- L July 12, 1949. s. GOLBERT 2,476,038

- MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 7 [n Yen to)- SER E GOL 55m Attorney:

July 12, 1949.

MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed NOV. 1, 1945 9 Sheets-Sheet 8 1.76 154 m5, 0 I I o FieQO Rlll ll/ I Inventor SERGE GoLBERT 4 a I flzzorneys s. GOLBERT 2,476,038

July 12, 1949.

s. GOLBERT 2,476,038 MACHINE USED FOR THE ASSEMBLY OF LARGE SIZED METAL PANELS Filed Nov. 1, 1945 9 Sheets-Sheet 9 [)Weh/or SERGE GOLBERT Patented Jul 12, 1949 UNITED STATES PAT ENT F Fl C E MACHINE USED FOR r s ASSEMBLY OF LARGE-SIZED METAL PANELS Application November 1, 1945, Serial No. 626,059 In France June 6, 1945 This invention relates to certain improvements in machines used especially in aircraft construction for assembling panels or stiffened metal sheets of large dimensions, and for securing to such panels stiffeners, flanges, ring-frames and the like.

Where panels of small dimensions are being manufactured, the assembling machine (riveting or spotwelding machine) usually remains stationary and the part is generally displaced by hand, or as the case may be, with the help of a small monorail or of any other suitable means.

In the known processes; the spot welding or the mechanical riveting of large panels having a double curvature, for instance, generally gives rise to considerable drawbacks because of the great number of displacements to which the to be assembled must be subjected in order to obtain the suitable positioning thereof with respect to the machine whicli isfixed'.

The chief diificulty consists less in the weight of the element than in its dimensions which may be as large as 33 feet. Moreover in some cases the load may also be considerably high because the element is too fragile and must bemaintained for assembly on a frame. The methods which be used are therefore different from the case of small elements.

The main object of the invention is to provide an improved method for assembling large sized metal panels and for securing to such panels stiifeners, flanges, ring-frames and the like.

Another object of the invention is to provide a method in which the assembling machine, which is carried by a movable frame, is angularly and translationally displaced whereby, when opera tive, at any assembly point the perpendicularity of the assembly means to the surface of the panels to be assembled is obtained, whatever the curvature may be at this point, while said panels are rightly set in any required position at the starting of: the operation.

Another object of the invention is to provide an assembling machine of the character described in: which the angular and translational displaceand translationaldisplacements of the assembling 17 Claims. (01. 219'-4')'.

machine, in relation to the required spacing between twoconsecutive assembly points for a step to step displacement parallel to the assembly line, and, at once, forthe other angular and translaticnal displacements in relationto the tangent plane ataii-y assembly point.

Further advantageous features of the invention will be made clear from the following descriptionreferring to the accompanying drawings given by way of example only and wherein Fig. 1 is a diagrammatic perspective view of a machine improved according to the invention.

Figs} 2 to 15' represent anexemplary practical embodiment of a-machine according to the inventi'cnnamely Fig. 2- is-adiagrammatic perspective view showing the suspending means of an assembling machine whe'rein the assembly tools are horizontally disposed.

Fig. 318 a diagrammatic perspective view showing the distribution on a gantry, not shown, of the controls ensuring all movements of the machine.

Fig. 4 is aviewpartly in elevation and partly in section of the whole apparatus in mounted condition.

Fig. 5- is a view from the left partly in section corresponding to Fig. 4.

Fig. 6 isa partial plan-view of Fig. 5 showing the mechanismcontrolling the pivoting motions of the machine in a horizontal plane.

Fig- '7 is a diagrammatic view in perspective at smaller scale of stationary rails and longitudinal and transverse cars.

Fig. 8 isa diagrammatic view in perspective on a smaller scale ofa gantry and a transverse car.

Fig. 9 is a diagrammatic view in perspective of an alternative embodiment corresponding to Fig. 8 with' a longitudinal car.

Figs.- 10 and II are diagrams showing the relative positions'of the gantryandof the longitudinal car in operation.

Figs. 12 and 13 are diagrammaticviews in elevation showing the vertical and horizontal distances by which the machine is offset and which should be compensated: for, in order to bring the ends of the assembly tools back to: the same horizontal plane, whatever the: angular setting and the curvature of the panels to be assembled may be.

Fig. 14 is a plan view corresponding to Fig. 13 showing the error made inthe spacing of the welding spots or the rivets by rotating the machine in a horizontal plane after the transversal compensation has} been cheated.

Fig. 15 ls-adiagrammatic elevationalview showing the device which may beused to ensure coincidence for all positions between the vertical pivotal axis of the machine and the ends of the assembly tools.

Fig. 16 is a diagram of the electric, oil and air circuits controlling the various movements of the machine.

Figs. 17, 18 and 19 are diagrams of the contacting devices.

Figs. 20 and 21 diagrammatically represent the combined control enabling the movements, in relation to the tangent plane atthe assembly point, to be carried out. s

Fig. 22 represents a similar device to the one shown in Figs. 20 and 21, but using photo-electric cells.

The accompanying drawingsshow a spot-welding machine with horizontal electrodes of a known type as adapted to a suspending device according to the invention. However, in the event of a welding or riveting machine of a different type, having for example vertical electrodes or rivet stamps, the device may be used in a similar manner without considerable alterations. In order to simplify the various movements of the machine, which should be effected rapidly for a satisfactory output, the panels and the parts to be assembled should be correctly positioned; for example, when assembling panels with plane stiffeners, the edge of the latter should be contained in a horizontal plane, which eliminates the necessity of vertical displacement.

This result is obtained by fixing the panel to be assembled on a support which may be angularly positioned in any desired position.

The necessary displacements may be effected as shown in Fig. 1 which is a theoretical diagram applicable to all machines according to the invention. The assembling means (welding or riveting means generally), which may either be of any known type or else especially designed for mounting on a machine according to the invention, is diagrammatically represented by two electrodes a and b. It may be pivoted about a horizontal axis XX perpendicular to the electrodes and intersecting them at their point of contact. It is carried by a carriage c slidably mounted on a frame 01 whereon it may be subjected to vertical displacement. Said frame d may rotate around a vertical axis YY intersecting axis XX at the point where said axis XX intersects the axis ZZ of the electrodes, so that the rotations will not generate a displacement of the electrodes. Where such condition may not be fulfilled, the possibility of correction should be provided for to compensate for such displacement. The axis of rotation YY' is rigidly connected with a carriage e which is turn is carried by a carriage i slidably mounted on the bed g of the machine, which, according to the working conditions which are to be obtained may be either a foundation anchored to the ground, or the frame of a travelling crane fixed or carried by a gantry, as will be described hereafter. The carriage e slides along the carriage 7 along a direction perpendicular to the direction of displacement of the latter with respect to the bed 9.

It is evident that any embodiment of a machine providing for all five displacements defined above remains within the scope of the invention. By way of example only, a machine according to the invention will be hereinafter described in greater detail.

As illustrated in Figs. 2 3, 4, which show embodiments, modified as to certain constructional details, the assembling (welding or riveting) machine M having for instance horizontal assembly tools (electrodes or rivet stamps) is fixed at four points, for example on a frame I provided on its two upper cross members l and l with two runways I and I engaging rollers 2 rotatably mounted on the yoke 3 whereon the machine M is suspended, said yoke carrying a vertical tubular member 4 having an annular section.

Said tubular member 4 is slidably mounted in a swiveling sleeve member 5 supported by a ball thrust bearing 5*; it is fixed to a transverse slideblock 6 comprising assembled channel irons and rollers journaling on said irons and running along rails 1 welded to the inner faces of the cross members of the longitudinal slide member 8. Said slide member 8 travels along runways provided on the upper horizontal platform of a gantry 40 constituted by squared metal box girders braced and assembled by means of welded gussets for example.

For the longitudinal displacement of the machine, several alternative systems may be provided:

1. As illustrated in Fig. '7, the longitudinal slide-member or carriage 8 runs on rails I21 supported by stationary posts I22 and carries rails 123 on which runs the transverse slide-block 6. Said embodiment requires a considerable amount of framework and would only be advantageous for lengthy operations.

2. As illustrated in Fig. 8, the transverse slideblock 6 runs on transverse rails I24 provided on the upper platform of a gantry I25 which travels, as a movable crane, on rails I26 fixed on the ground. Said embodiment is more simple than the first, but the load to be displaced during operation is greater, which constitutes a considerable drawback inasmuch as the longitudinal displacement should be carried out rapidly.

3. As illustrated particularly in Figs. 9, 10 and 11, and as a compromise between the preceding embodiment, the longitudinal carriage 8 travels along rails provided on the upper platform of a gantry 40 provided with rollers 81 moving on a runway. The longitudinal carriage 8 may have a run comprised of from 3,3 feet to 6,6 feet, whereby it will not be possible to assemble the panels by means of a single operation; it will be necessary to move the gantry 40 after having brought back the longitudinal carriage 8 to its initial position.

Applying a different method, the longitudinal displacement of the carriage, to which the panels to be assembled are secured could, in a similar way, be effected; the assembling machine being suspended to a fixed frame-work. Such disposition requires a considerable extent of framework, but the loads to be displaced are less heavy especially in the case where short panels are being assembled.

Apart from the machines various movements namely: rotation in a horizontal plane, rotation in a vertical plane, longitudinal displacement, transverse displacement and vertical motion, it may be necessary to provide two additional motions to compensate for the theoretical error owing to the fact that the vertical pivotal axis does not pass through the point of contact of assembly tools, but passes through the center of gravity G of the machine located below the suspension points thereof (Fig. 12).

The pivoting of the machine in a vertical plane, required to suitably position the assembly tools with respect to the tangentto the vertical curve of the work in said plane, along the line of assembly, causes a transverse offset of the axis of the machine equal to the distance AB, and a vertical oiiset equalto the distance CD (Fig. 13), since the point of contact of assembly tools E should at all times be contained in the same horizontal plane in order to provide a straight line of assembly. The vertical compensation or correction is obtained by means of runways l and I provided with a suitable curved shape and the transverse or horizontal compensation or correction is accomplished by means of the slide member or carriage 6 controlled by a feeler as will be explained below.

This last mentioned transverse displacement causes the pivotal axis of the machine to be offset in a vertical plane, which will therefore no longer pass through the contacting point of assembly tools and causes an error in the longitudinal spacing OF equal to the distance EF (Fig. 14). In the event the vertical distance (Fig. 12) equals 6,6 feet, for an angle a. equalling 15", a spacing of 1%" and a horizontal radius of curvature equal to 33 feet for example, the error the spacing will be approximately .04, but curva tures and spacing are generally smaller than those given above and the error in spacing may be regarded as negligible. However such error could be avoided altogether by providing the displacement of assembly tools along their (Fig. 15), thus eliminating the horizontal compensation. In such conditions, the pivotal axis of the machine in a Vertical plane is no longer offset, but the control of the contacting tools should be synchronized with the control of the displacement of the suspending roller 2, and the shape of the runway I will be diiferent from the shape used for vertical compensation.

All the controlling means of the machine, except the vertical displacement control, are automatic, the intermittent advance or feed corresponding to the longitudinal spacing, and the welding or riveting operation being likewise automatically operated; all the positioning movements are controlled by electric feelers, whereby the contacting electrode or rivet stamp is maintained in contact with the work While, at the same time it is thereby positioned in a direction perpendicular to the curvature of said work along the line of assembly.

The control of the various movements for angularly positioning and displacing the machine and compensating or correcting the positions thereof is for example embodied as shown in the diagram of Fig. 16 and may be analyzed as follows:

1. Control of the vertical displacement Vertical displacement along the axis of the tubular member 4 (Fig. 3) is obtained by means of a hydraulic jack 9 the fixed piston in of which has its shank Ill anchored to the lid I! of a second tubular (member H the base N of which bears on a disk or washer 8| fixed in turn to a rotating sleeve rigidly connected to the first tubular member 4, the cylinder 9 of the jack being coaxially secured to the top of said first tubular member. The jack 9 is controlled through two valves, an inlet valve l2 and a discharge valve 53, controlled by electric contacts 84 and !5 (Fig. 16) actuated by hand, the oil being in neutral position remaining within cylinder 9 An automatic control has not been contemplated for the vertical displacement of the machine, because in the event where ring frame flanges are being welded to the fuselage of an aircraft for example, it is difficult to provide a constant spacing in consequence of the frequent interruptions made necessary by the presence of longitudinal stringers. However, there may easily be provided automatic control for certain applications in any given branch of the art, simply by means of a cam or of a cam surface. In the latter case, there may even be contemplated a variable vertical spacing in connection with the distribution of obstructions fixed to the panels, such as stiffeners or the like. It is obvious that the smaller the spacing, the greater may be the rate of output. In the case where an angle iron for example is being welded along an approximately but not exactly horizontal line, the displacement of the machine may easily be made automatic as follows (Fig. 17); the contacts 2| and 22 are controlled by a feeler 21 contacting the angle iron 2| said feeler having to be previously fixed in position by a spring 2 I.

The pressure feed of the jack 9 is effected by means of a compressor I6 having a constant rate of how, driven by an electric motor 18, connected to a pneumatic accumulator I! which also supplies oil to: the jacks l8 and N for locking the machine at a given obliquity in a vertical plane, to the jack ill for controlling the pivotal movements in a horizontal plane and to the jacks 20 for controlling longitudinal displacement. When calculating the rate of flow of the compressor IS, the jack 29 may be omitted as it does not operate at the same time as the raising jack 9. The other jacks which have a very small oil displacement can also be disregarded.

Contacts 2! and 22 induce starting or stopping of the electric motor l8 of the compressor it according to the oil level within the pneumatic accumulator H. In normal use, the coil 23 (Fig. 16) is not supplied with current and the contacts 2| and 22 are closed. As soon as the floater 2 reaches its maximum level and closes the contact 2!, the coil 23 is energized, opens the contact 25 and stops the motor l8. The oil level within the accumulator l'l goes down again, but the motor I8 remains dead in spite of the fact that contact 2! is open, as the coil 23 is energized through the closed contact 26. When the oil is at its lowest level in accumulator II, the floater 24 closes the contact 22, the coil 26a is energized and opens the contact 21; the coil 23 which is no longer supplied with current', closes the contact 25 which starts the motor l8. If the floater 24 rises once more in the accumulator H, the motor l8 continues to rotate in spite of the closing of contact 21, since contact 26 is open.

In the diagram of Fig. 3, motor l8 and compressor l6 have been illustrated as fixed to beds located on each side of the suspending yoke 3 and directly coup-led, but in the embodiments illustrated in Figs. 4 and 5, though a similar arrangement as the one shown in Fig. 3 has been adopted, wherein there is provided a transmission using a V-shaped belt, having a reduction ratio proportional to the respective velocities of the motor I8 and the compressor I6. The lower portion 4 of the vertical tubular member 4 having an annular section, thus offering satisfactory resistance to torque, serves as an oil container and is for this purpose made oil tight.

In order to reduce the weight of movable mem bers, the compressor unit could have been located on the gantry 40. In that case, oil supply to the hoisting jack 9 and to the locking jacks Ill and la would be rovided by means of flexible piping aevaoae but, in consequence of the high pressure used (2100 lbs/sq. in.) it is preferred to use flexible piping only for the supply of the jacks having a small oil displacement and to place the compressor unit on the elements carrying the main jack, namely on the suspending yoke 3.

2. Control of the longitudinal displacements (a) Intermittent spacing of the longitadinalcarriage- 8.-The translation of carriage 8 is effected by means of a pinion 28 controlled by a jack through a pawl 30 and ratchet wheel 3! in mesh with a rack 29 pivoted in a yoke 32, rigidly connected to the carriage 8 and guided within two rest members 33 fixed to the gantry 40 (Fig. 4). The jack 20 is set in motion by the displacement of the contact 32 which closes the circuit of the coil 33 and places the valve 34 in its position of admission; a cam 35 actuated by hand or through an electric motor 36 provided with a reduction gear closes the contact 32 at regular intervals. The rate of operation is given by the rate of rotation of the cam 35. carriage 8 closes the contact 31, the coil 38 is supplied with current and opens the contact 39 which may only be put back in closed position by hand.

The return run of the jack 2i) and of the pawl 30 is efiected by means of springs, the release spring of the pawl having sufiicient strength to provide a braking eifect on the ratchet wheel 3!.

As information, the average rate of displacement of the carriage 8 is about 4 ft. per minute; there will thus be needed about 2 seconds to effect a translation corresponding to the maximum longitudinal spacing 1%", the corresponding speed of the jack 20 being then equal to 10 feet per minute.

(b) Displacement of the gantry 40 and quick return motion of the carriage 8.-As stated above, the gantry 40 should be displaced after the longitudinal carriage B has performed its whole run thereon. The opposite translations of the gantry 40 and of the carriage ll are synchronized (Figs. 10 and 11) so that said carriage will remain in the same relative position with respect to the fixed point constituted by the last welding spot or rivet set in place on the work. The control of both these translations is effected by means of the motor 4!. By pushing on the button 42 which controls the displacement in the direction of the work, the motor M is started and simultaneously current is supplied to the coil 43, which opens the valve of the jack 44 which operates the dog clutch bar 84. In that position, the pinion 28 is disconnected from the pawl control and in mesh with the transmission shaft 35 connected to the electric motor ll and fitted on the gantry 40. The jack 44 may be selected of the same power as the jack 2%! because the connection of dog clutch bar 84 requires a strong axial pressure. w

It is not necessary to press on the button 32 during the displacement of the carriage 3 and of the gantry 40, since by closing the main contact, the auxiliary contact 45 is simultaneously opened. At the end of the quick return run, a stop member opens the contact 46 and stops the motor li. Such opposite displacements of the gantry 49 are achieved by means of the contact 41, but in that case the carriage 8 is not positive driven. The transmission of the rotational movement to the driving wheels 8'! of the gantry 49 is efiected by shafts such as 85a and 86 carried by bearings fixedly secured on the framework and which are operatively connected between each other and to the motor 4|, on one hand, by means of a bevel gearing and 89 and, on the other hand, by

At the end of its run, the

ail)

means of a unit comprising a reduction gear, a worm wheel and a worm gear.

For forward displacements of the gantry, displacements in the direction of the feed of the work without translation of the carriage 8 in the opposite direction, the control system of the jack 44 is eliminated by switching the contact 48. During the welding or riveting operation 1. e. when motors 36 are running, the gantry 40 may not be displaced as the contact 39 is open; conversely if the motor 4! is running, riveting or welding is impossible because the circuit is then broken by the switch 50.

3. Control of the pivoting displacement in a horizontal plane The rotation is controlled by the jack l9 actuating the toothed sector 5| coaxial with the tubular member 4 and locked thereon by means of a rack 52 guided within a fixed supporting member on the transverse carriage 6, the maximum angular run in each direction being limited to 20, for example. The jack I9 is operated by means of the

coils

53 and 54 actuating the

valves

55 and 56 and the supply circuit of which is controlled by the fee-lei 5'! in connection with the horizontal curvature.

If the axis of the electrodes E is perpendicular to the surface of the work, the feelers 51 remain in neutral position and the

contacts

58 and 59 are open. If, during the advance motion of the machine, a variation occurs in the curvature of the work, the feeler Bl pivots about a vertical axis and closes one of the contacts 58 or 59 (Fig. 18) the corresponding

coil

53 or 54 is then energized and one of the

valves

55 or 56 is opened.

The jack i9 is thus displaced in the appropriate direction, until the electrodes are located in a plane perpendicular to the Work. At that instant, the feeler 5'! returns to neutral position and stops the rotation, which may likewise be hand controlled by the buttons 60 and 6!. The minimum angular displacement causing the feeler 51 to start actuating the contacts should be of the order of about 1; the feeler should, moreover, be resiliently secured in the longitudinal direction to avoid deterioration thereof during lateral displacements of small amplitude. As the frequency of operation is very great (10 to 15 pivoting displacements per minute) it is necessary, on one hand, to provide very strongly constructed electric controls, and, on the other hand, to bring the inertia to a minimum, as the total time, during which the machine should be positioned, should be comprised between one and two seconds.

4. Control of the pivotal displacement in a vertical plane Such control is essentially carried out in the same way as the control of pivoting in a horizontal plane; in this case however the coils 62 and 63 control a reversing switch 64 adapted to reverse the rotation of the motor 55 according to the direction of inclination which should be given to the machine. Pivoting in a vertical plane is caused by the displacement of the suspension points of the machine 1. e. of the rollers 2. To provide for vertical compensation, indicated by the straight portion CD of Fig. 12, the pin of each roller 2 is fixed on an intermediate member 66 slidably mounted on the nut-carrying member 61, which in turn is guided along two

bars

68 and 69 rigidly secured to the frame I. On the diagram shown in Fig. 3 there are provided two half frames l secured on either side of the machine; in that case, the control of the pivotal displacement in a vertical plane is effected by means of a unit I0, comprising a worm gear and a worm wheel, driven by a motor 65 carried by the frame I, two bevel pinions II being provided at both ends of the shaft 9| rotatably mounted in supports fixedly secured to the vertical members of the frame I, and at the corresponding end of each of the screws I2.

In the embodiment illustrated in Figs. 4 and 5, a single frame I bridges the transformer I3 and a single control screw I2 is provided between the rimmed rollers 2. Such an arrangement is more simple than that first described, but increases the necessary height of the gantry 40. In consequence of the frequency of starts, a somewhat low working ratio is selected for the intermediate transmission members. The motor is provided either with a brake having an electromagnetic release system, or with a counter current braking system. Moreover it is possible that such braking device will not be indispensable in the event the power transmission between the motor and the machine is effected by means of a worm gear.

5. Control of the transverse displacement This automatic control is carried out by means of a feeler or contactor I4 slidably mounted in a direction perpendicular to the bearing surface and which actuates contacts I5 or 16 (Fig. 19). The sensibility of such contacts should be of the order of .016" which requires the use of an amplifying device. Such lateral displacement of the machine may likewise be controlled by pressing buttons 11 or I8 according to the sense of translation desired.

The electrical controls are based on the same principle as in the last two control means described and will therefore not be described again,

The motor 92 for controlling the lateral displacement is fixed on the longitudinal carriage 8; on the motor shaft is keyed through a reduction gearing a pinion for the control of a set 94 of gears, one of which 95 acts as a nut actuating to rotate in one or the other direction a screw 93 having trapezoidal threads and secured by a yoke 96 to the carriage 6.

6. Control for locking the machine after pivotal displacement iii 6 bet-tied! plane The movement of the machine is locked, when welding or riveting is to be carried out, by means of two opposite jacks I8 and I8 housed in the suspending yoke 3 and controlled through a coil 19 shunting the control circuit of the machine itself.

Instead of supplying all the jacks from a single compression unit at a pressure of 2100 lbs/sq. in., it is possible to provide a special unit providing a somewhat lower pressure for the less powerful jacks with a View to avoiding the use of high pressure flexible connections.

There may also be provided a combined control system for the two pivotal displacements and the transversal displacement, in connection with the position and the shape or the surface of the work. Such a system is diagrammatically shown in Figs. 20 and 21. Three feelers 99, I00 and IOI contact the surface of the work and are distributed along a circumference of about 4 to 6" in diameter. It may be admitted that the three points of contact with the work are sumciently close to each other as to define a tangent plane to the surface. Three levers I02, I03 and I04 operate to transfer the displacementof the feelers to the side of the machine in order to free the central portion wherein are located the rivet stamps or the electrodes. The ends I30, I3I and I32 of the levers bear on a disk member I05 carrying at the opposite side a spherical element I06 and operate to maintain said disk member at all times parallel to the tangent plane (or in symmetrical planes thereof). Moreover the supporting frame IE8 of the disk member is longitudinally slidable to compensate for the displacement of the tangent plane. The contactor I4 provides through contacts I5 and I6 for the corresponding transverse displacement of the machine. A spring I01 maintains parts I08 and I06 and the levers of the feelers in contact with respect to each other. The disk member carries a contactor H89 the end of which is displaceable on a sphere concentric to the spherical element of the disk member. Said sphere is divided into five portions. The central portion I33 corresponds to neutral position (machine at rest). The four other portions I34, I35, I35 and I3! are electrically connected respectively to relays 53, 54, 62 and 63 controlling the two pivotal displacements of the machine (see Fig. 19);

As the contactors may be subject to wear, a different form of embodiment, comprising an arrangement similar to the aforesaid arrangement may be contemplated. Such embodiment consists in substituting photo electric cells for the contactor. Such disposition is stronger, probably ofiers less inertia, and is diagrammatically illustrated in Fig. 22. The cell IIO controlling the pivotal displacements is, similarly to the sphere of the preceding embodiment; divided into five zones each of which is electrically connected to the relay controlling the corresponding displacement. The contactor I09 carried by the disk member is replaced by a mirror II I reflecting onto the cell the image of a luminous source I I2. Similarly contacts I5 and 16 are relaced by a cell II3 divided into two zones each of which is connected to the corresponding relay controlling the transverse displacement and receives the luminous spot reflected from a luminous source I I4 by a mirror II5 carried by the contactor 14. v

As illustrated in Fig. 16,- the electrical controls and all the elements of such controls have been represented adjacent to the corresponding motors in order to make the drawing more easily understandable. Practically, such controls should be grouped in a single box located at the lower portion of the gantry as well as all the contactors and buttons which should be combined on a single switchboard readily accessible to the operator of the machine. The box containing the condensers 91 of the supply circuit of the machine proper is fixed to a' platform 98 located on the gantry or at any other convenient location.

The electric power is supplied by means of a trolley, the movable elements being connected thereto by means of flexible connections.

The contactors should be strongly constructed and have a very low inertia in consequence of the frequency of starts (10 to 15 per minute); according to the spacing between welding spots or rivets the complete operation cycle is effected in four or five seconds.

All the positioning displacement of the machine. namely the two pivotal displacements and the transversal displacements should be carried out simultaneously with the longitudinal displacement.

All the elements of the-electric. controls are supplied through the circuit 80 and, so long as there is at least one element of the machine in motion, the Welding or riveting operation may not take place as thecontactor 50 opens the corresponding circuit. H

The invention is of course not to be considered as restricted by the examples of embodiment as represented and describedherein. The invention is defined by its essential features as described at the beginning of the present application and comprises within its scopeall means and combinations of means suitableto embody such features.

What I claim as my invention and desire to secure by Letters Patent is:

1. An apparatus for the assembly of large sized panels comprising means for supporting said panels to be assembled, means for rightly setting said supporting means in the initial required position, means for maintaining said supporting means in said initial position during the assembly Work, assembly means, means for translating said assembly means along three distinct axes, means for pivoting said assembly means in a plane tangent at any assembly point to thesurfaoe of said panels to be assembled until it is contained in the plane of greatest incline and means for pivoting said assembly means in said plane of greatest incline, whereby said assembly means are positioned in a directionno'rm'al to the surfaces of said panels to be assembled, Whatever the curvature of said surfaces may be at the assembly point;

2. An apparatus for'the assembly of large sized panels comprising means for supporting said panels to be assembled, means for rightly setting said supporting means in the initial required position, means for maintaining said supporting means in said initial position during the assembly work, assembly means, a composite travelling frame for suspending said assembly means comprising a first part on which said assembly means are fixed and pivotable around a vertical axis intersecting said assembly'means at their point of contact, a second part on which said first part is pivotally mounted and a third part longitudinally movable with respect to the assembly line and on which said second part is transversally movable with respect to said line, means for pivoting said assembly means according to the vertical curvature of the panels at any assembly point about a horizontal axis perpendicular to the same and intersecting said assembly means at their point of contact, means for displacing vertically said assembly means according to the height of the assembly point,-means for pivoting the first part of said frame according to the horizontal curvature of said panels at said assembly point, means for transversally displacing the second part of said frame on said third part according to the transverse position of said assembly point and means for effecting an intermittent longitudinal movement of the third part of said frame according to the spacing between two successive assembly points. j

3. An apparatus as claimed'in claim 2, in which the third part of the composite frame comprises a gantry on which the second part comprising a carriage is transversally movable, H

4. An apparatuses claimed in claim 2, in which the third part of the composite frame is also composite and comprises a gantry longitudinally movable with respect to the assembly line and a carriage longitudinally movable on said gantry with respect to said line and on which the second part is transversally movable, whereby the assembly for a set of assembly points located in a determined region of the panels may be effected without longitudinally displacing the gantry the load of which is important.

5. An apparatus for the assembly of large sized panels comprising means for supporting said panels to be assembled, means for rightly setting said supporting means in the initial required position, means for maintaining said supporting means in said initial position during the assembly work, assembly means, a composite travelling frame for suspending said assembly means comprising a first part on which said assembly means are fixed and pivotable around a vertical axis intersecting said assembly means at their point of contact, a second part on which said first part is pivotally mounted and a third part longitudinally movable with respect to the assembly line and on which said second part is 'transversally movable with respect to said line, means for pivoting said assembly means according to the vertical curvature of the panels at any assembly point about a horizontal axis perpendicular to the same and intersecting said assembly means at their point of contact, means for displacing vertically said assembly means according to the height of the assembly point, means for pivoting the first part of said frame according to the horizontal curvature of said panels at said assembly point, means for transversally displacing the second part of said frame on said third part according 'to the transverse position of said assembly point, means for effecting an intermittent longitudinal movement of the third part of said frame according to the spacing between two successive asembly points and means for controlling said two pivoting means and said transversal displacing means in relation with the tangent plane to said panels at the assembly point. 7

6. An apparatus as claimed in claim 2, in which thethird part of the composite travelling frame, comprises a carriage adapted to support the two first parts of said frame and tobe longitudinally displaceable, and in which the means for eifecting an intermittent longitudinal movement of said third part of the composite frame, comprises a horizontal longitudinal member rigidly connected to said carriage, means for displacing longitudinally said member, means adapted to operate step by step said displacing means in relation with the required spacing between two consecutive assembly points and means for stopping said step by step operative means at the end of the longitudinal displacement of said third part. e

'7. An apparatus as claimed in claim 2, in which the third part of the composite travelling frame, comprises a carriage adapted to support the two first parts of said frame and to be longitudinally displacea-ble and a gantry adapted to supportsaid carriage and to be longitudinally 'displaceable, and in which the means for the longitudinal intermittent displacement of said third part of the frame, comprises a horizontal longitudinal member rigidly connected to said carriage, means for displacing longitudinally said member, means carried by said gantry adapted to operate step by step said displacing means in relation with the required spacing between two consecutive assem-- bly points, means for stopping said step by step operating means at the end of the longitudinal displacement of said carriage on said gantry, secondmeans for longitudinally displacing said gantry after said carriage has performed its whole run thereon, means for actuating said first displacing means in relation to the longitudinal displacement of said gantry so that said carriage remains in a position corresponding to the last point assembled, means for connecting said first displacing means with said step by step operating means and for disconnecting the same from said actuating means and inversely, and means adapted to stop said actuating means at the end of the relative longitudinal displacement of said gantry regarding said carriage.

8. An apparatus as claimed in claim 2, in which the means for the vertical displacement of the assembly means, comprises a vertical member carried by said composite travelling frame adapted to carry said assembly means and means for vertically displacing said member regarding the movable parts of said frame.

9. An apparatus as claimed in claim 2, in which the means for the vertical displacement of the assembly means, comprises a vertical member carried by said composite travelling frame a dapted to carry said assembly means, means for vcrtically displacing said member regarding the movable parts of said frame and means adapted to operate step by step said vertically displacing means in relation with the required spacing be tween two consecutive assembly points.

10. An apparatus as claimed in claim 2, in which the first part of the composite travelling means comprises a vertical member carried by said composite travelling frame adapted to carry the assembly means and to pivot around a vertical axis perpendicular to the horizontal axis perpendicular to the assembly means and intersecting them at their point of contact, and in which the means for the pivoting of the first part of said composite frame around a vertical axis comprises a feeler contacting at least one of the surfaces to be assembled, means adapted to pivot said member till said assembly means are perpendicular to the surfaces to be assembled when said feeler is displaced from its neutral position by a change in the horizontal curvature of said surfaces, and means for stopping said pivoting means when the assembly means are perpendicular to the surfaces to be assembled and for returning said feeler in neutral position.

11. An apparatus as claimed in claim 2, in. which the means for pivoting the assembly means about a horizontal axis perpendicular to the same and intersecting them at their point of contact, comprises a member carried by the composite travelling frame adapted to carry said assembly means and to pivot about said horizontal axis, a feeler contacting at least one of the surfaces to be assembled, means adapted to pivot said member till said assembly means are perpendicular to the surfaces to be assembled when said feeler is displaced from its neutral position by a change in the vertical curvature of said surfaces, and means for stopping said pivoting means when the assembly means are perpendicular to the surfaces to be assembled and for returning said feeler in neutral position.

12. An apparatus as claimed in claim 2, in which the means for pivoting the assembly means about a horizontal axis perpendicular to the same and intersecting them at their point of contact, comprises a member carried by the composite travelling frame adapted to carry said assembly means and to pivot about said horizontal axis, a feeler contacting at least one of the surfaces to be assembled, means adapted to pivot said member till said assembly means are perpendicular to the surfaces to be assembled when said feeler is displaced from its neutral position by a'change in the vertical curvature of said surfaces, means for stopping said pivoting means When the assembly means are perpendicular to the surfaces to be assembled and for returning said feeler in neutral position, means for compensating the horizontal offset of said assembly means induced by said pivoting movement and means for compensatin the vertical offset of said assembly means induced by said pivoting movement.

13. An apparatus as claimed in claim 2, in which the second part of the composite travelling frame, comprises a carriage adapted to support the first part of said frame and to be trans versally displaceable, and in which the means for the transverse displacement of said third comprises a horizontal transverse member rigidly connected to said carriage, a feeler contacting at least one of the surfaces to be assembled and means for transversally displacing said member in relation with the displacement of said feeler.

14. An apparatus as claimed in claim 2 comprising means for locking said apparatus when operative after pivotal displacement in vertical plane.

15. An apparatus as claimed in claim 5, in which the means for operating the three last movements in relation to the tangent plane to the panels at any assembly point, comprises a set of three feelers for contacting at least one of the surfaces to be assembled along a circumference the center of which is the assembly point, a plane surface, means for transferring the displacements of said feelers to said plane surface for maintaining the same parallel to the tangent plane at the assembly point, and means connected to said plane surface for operating said three movements for compensating the movements of said plane surface, in order to maintain said assembly means at any assembly point in a direction normal to the tangent place.

16. An apparatus as claimed in claim 5, in which the means for operating the three last movements in relation to the tangent plane to the panels at any assembly point, comprises a set of three feelers for contacting at least one of the surfaces to be assembled along a circumference the center of which is the assembly point, a plane surface, means for transferring the displacements of said feelers to said plane surface for maintaining the same parallel to the tangent plane at the assembly point, a spherical element carried by said plane surface, a supporting frame having a spherical recess on which bears said spherical element, adapted to slide transversally in relation to the transverse displacement of said plane surface and having a spherical surface concentric to said spherical element divided into five portions, one portion. corresponding to neutral position and the four other corresponding two by two to each of said pivotal displacements, a fourth feeler connected to said supporting frame adapted to operate the means for the transverse displacement in relation to the sliding movement of said supporting frame and a fifth feeler carried by said spherical element adapted to bear on said spherical surface and to operate the means for the pivotal displacement corresponding to the one of said four portions on which it bears.

1'7. An apparatus as claimed in claim 5 in which the means for operating the three last movements in relation to the tangent plane to the panels at any assembly point; comprises a set of three ieelers for contacting at least one of the surfaces to be assembled along a circumference the [center of which is the assembly point, a plane mirror, means for transferring the displacements of said feelers to said plane mirror for maintaining the same parallel to the tangent plane at the assembly point, a spherical element carried by said plane mirror, a'supporting frame having a spherical recess on which bears said spherical element, adapted to slide transversally in relation to the transverse displacement of said plane mirror, a first luminous source, for lighting the center of said mirror, a first photo electric cell for receiving the luminous ray reflected by the center of said mirror and divided into five portions, one portion corresponding to neutral position and the four other corresponding two by two to each of said pivotal displacements, a fourth feeler connected'to said supporting frame, a second mirror carried by said fourth feeler, a second luminous source for lighting the center of said second mirror, a second photo electric cell for receiving the luminous ray reflected by the center of said second mirror and divided into three portions, one'po-rtion corresponding to neutral position and the two other to said transverse displacement, means for operating the means for the transverse displacement when the luminous ray reflected by 16 the center of said second mirror is intersected by one of the two operative portions of said second cell and. means for operating the means for the pivotal displacement corresponding to the one of the four operative portions of said first cell which intersects the luminous ray reflected by the center of said first mirror.

SERGE GOLBERT.

REFERENCES CITED The following referenlces are of record in the file of this patent:

UNITED STATES PATENTS