DE2806185A1 - WELDING MACHINE - Google Patents

Description

DESCRIPTION

The invention "relates to welding machines that use it enable workpieces or parts of workpieces to be brought into the correct position automatically and precisely and with one another to weld and eject the welded workpieces from the machine.

In the case of repetitive work to "weld similar parts, it is necessary to weld the To bring parts exactly into the correct position relative to one another and to place them in relation to one another during the welding process Support welding head; It is also necessary to remove the workpieces quickly after the welding process, around the welding machine to pick up the next to be welded Parts ready to make.

It is particularly difficult to align adjacent edges of workpiece sections exactly with one another, so that they can be welded together with the help of plasma welding heads. With such welding devices it is necessary the edges to be welded very precisely into the

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to bring the correct position to each other, with the workpiece sections after the start of the welding process their position to one another remain unchanged, which is in contrast to Determine sink welding procedures in which the to Welding bands are pressed against each other with force in order to shift part of the metal, the is brought to melt during the welding process.

The invention is based on the task of an automatic To create welding machine that makes it possible to relatiyzu each other as well as adjacent edges of the workpieces to hold exactly in the correct position compared to a welding head, Furthermore, a welding machine is to be created, to which one teaching belongs, which is used to ensure that the edges to be welded are in exactly the right position to one another hold, this teaching also serves to eject the workpieces from the machine. Furthermore, a Welding machine are created in which the workpiece edges to be welded relative to each other and relative to the Path of a welding head held exactly in the desired position and welded together, the workpiece is ejected from the machine after welding, and with all operations at high speed expire. In addition, a welding machine is to be created in which the parts to be welded exactly into the be brought correct position against a gauge, whereupon the gauge is removed, and the edges to be welded be moved towards each other along a distance greater than the thickness of the gauge to ensure that the edges are pressed firmly together. Finally, a welding machine is to be created in which the to be welded Parts brought to rest on surfaces facing away from each other of a rail-shaped gauge and then be clamped so that it is possible to press the edges of the parts against the jig for precise alignment to ensure.

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According to the invention , this object is achieved by creating a welding machine in which the edges of workpieces that are to be welded in order to produce a finished product are arranged in such a way that they come to rest on a gauge which automatically moves into a rest position, whereupon the workpieces are brought closer to one another until they touch, with an even contact pressure being applied, the workpiece edges being arranged in the path of a movable welding head which is brought into a rest position after the welding process has ended, the teaching of the ejection of the welded workpiece effected from the machine, and all these work steps are synchronized so that large series of workpieces can be welded in quick succession.

An embodiment of the invention is explained in more detail below with reference to schematic drawings. It shows:

1 shows a side view of a welding machine according to the invention;

FIG. 2 shows the front of the welding machine according to FIG. 1; 3 shows the partial section 3-3 in FIG. 1;

Fig. 4 is a view of part of the welding machine of Fig. 2 on a larger scale as well as in one other operating state;

5 shows an illustration of the electrical control circuit and associated parts of the welding machine;

Fig. 6 is a view of part of the welding machine of Fig. 2 on a larger scale for illustrative purposes the initial position of the workpiece sections;

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FIG. 7 shows the clamping of the workpiece sections in a representation similar to FIG. 6; FIG.

8 shows, in a representation similar to FIG. 7, a further operating state of the welding machine; and

9 shows a representation similar to FIG. 8, from which the position of the workpiece sections during welding can be seen.

To the illustrated, generally designated 10 according to the invention Welding machine includes a welding head 12, a jig 14 and a jig 16, all of which be carried by a frame 18. The welding machine is particularly suitable for welding the edges 20 of a metal strip, which have been brought into contact with one another, which was previously generally the shape of a circular ring 22 has been given.

According to FIG. 2, the clamping device 14 includes an assembly 24 arranged on the left side and one on the assembly 26 arranged on the right-hand side, which serve to remove the associated edges 20 of the tire 22 during the welding process to hold in their position. A stationary workpiece support 28 belongs to the left clamping assembly 24, which is arranged in a stationary manner opposite the frame 18, and there is also a vertically movable clamping part 30, this with the aid of a hydraulic cylinder 32 in relation to the workpiece support 28 is generally perpendicular can be moved.

According to FIG. 2, a workpiece support 34 belongs to the clamping assembly 26 on the right-hand side the frame 18 is supported so that it is opposite de; ' Can move workpiece support 28 horizontally. to the workpiece support 34 includes a bearing block 36, which protrudes substantially vertically upwards, and a second

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hydraulic cylinder 38, the piston rod of which is connected to a clamping part 40. The cylinders 32 and 38 are for simultaneous actuation with a common source, not shown, for a hydraulic pressure medium connected, and they are inclined to the vertical at a small angle so that the clamping parts 30 and 40 relative to the hoop-shaped workpiece 22 move generally in radial directions around the edges 20 of the workpiece to be clamped or released again as required. The clamping part 40 is together with the cylinder 38 and the bearing block 36 as well as the workpiece support 34 can be moved horizontally. Such a movement can be brought about by a hydraulic actuating device 41 which can be retracted in order to move the said assembly according to FIG. 2 to the left, and which are extended to cause the slidable assembly to move to the right.

The jig 16 is supported on the frame 18 so that it is generally horizontal between its retracted position and their extended position can be moved, as indicated in Fig. 1 with solid lines or with dashed lines is. In its extended position, the jig 16 lies between the two clamping assemblies 24 and 26, with there is a gap between the clamping assemblies according to FIG. To move the rail-shaped gauge 16 is used a hydraulic cylinder 36 which rests on the frame 18 at the rear of the welding machine 10, generally horizontally is arranged

The tire 22 is inserted into the welding machine 10 when between the clamping assemblies 24 and 26 as shown in FIG there is a gap, for this purpose the edges 20 of the workpiece are placed on the left workpiece support 28 and the right workpiece support 34 so arranged,

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that they are in contact with teaching 16. Then the chucks 30 and 40 are opened with the aid of the hydraulic cylinders 32 and 38 moved down and brought to bear on the edges 20 in order to support them with the part supports 28 and 34 to be braced.

The welding head 12 is supported by an elevated rail arrangement 48, which forms part of the frame 18, and along which the welding head is movable. The welding head includes a welding nozzle 52, which in the preferred embodiment of the invention is a plasma welding nozzle is designed as described in US Pat. No. 2,806,124. According to FIG. 1, a generally belongs to the welding nozzle 52 perpendicular tubular section 52 for guiding the arc and the arc gases through. the Nozzle 52 is movable together with a guide part 54 which is pivotable about an axis 56 relative to a movable support structure in the form of a carriage 58. According to Fig. 1 is the carriage 58 is connected at its upper end to a grooved member 60 with which a tongue member 62 in sliding engagement is available, as shown in FIG. The tongue part 63 is with the rail construction 48 of the Frame 18 rigidly connected and has an approach of generally V-shaped cross-section, which is in the Longitudinally extending threaded spindle 66 cooperates. According to Fig. 1, the threaded spindle 66 is through a coupling 68 coupled to a direct current motor 70. The reversible and its speed can be changed. The rotational movement of the reversible motor 70 is through the Coupling 68 is transferred to the threaded spindle 66, the thread of which engages with a drive part 72 as shown in FIG which forms part of the grooved component 60. Thus, each rotation of the motor 70 causes itself the grooved component 60 moves relative to the tongue part 62, and that the welding nozzle 52 is moved accordingly. The movement of the welding nozzle 52 is used to actuate electrical

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shear switches that become a control circuit to be described belong.

Not only can the nozzle 52 be moved along the rail structure 48, but it can also be moved as shown in FIG about the axis 56 between that shown with solid lines Pivot position and the position indicated by dashed lines. Between the guide part 54 and the carriage 58 extends a tension spring 74, so that the welding nozzle 52 according to FIG. 1 constantly in the direction of its vertical Position is biased.

There is a limit stop in the path of movement of the welding nozzle 52 78 arranged so that when the welding head moves with the nozzle 52 according to FIG. 1 from left to right, the guide part 54 for bearing against the stop 78 comes to cause the welding nozzle and support member 54 to pivot to the position shown in solid lines will.

At a front part of the frame 18, the welding machine 10 is provided with a protective cover 80, which is between their open position and their closed position is vertically displaceable. The protective cover 80 is balanced by a counterweight 81, see above that the operator each with the protective cover must bring the hand into its closed position. Closing the protective cover also serves to engage it to bring with a locking device 82 so that it maintains its closed position, and aim to reopen the Protective cover, which is done electrically, an electromagnet is actuated, which is part of the locking device 82 forms. The protective cover 80 has the task of protecting the operator against the welding nozzle 52.

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Furthermore, a guide block 84 is arranged on a front part of the welding machine 10, which according to FIG V-shaped cutout 85 which receives the tapered front end 86 of the jig 16 to ensure that the gauge is exactly parallel to the rail structure 48 and therefore also parallel to the path of the welding head 12 is arranged. When the tapered end 86 of the jig engages the V-shaped cutout 85 stands, the gauge 16 is precisely aligned, and here the edges 20 of the workpiece are in contact with the gauge, so that they are exactly in the right position.

The two clamping assemblies are in the starting position of the welding machine 10, in which there is no workpiece in the machine 24 and 26 separated by a horizontal distance, and the teaching is shown in FIG Way arranged in between. The chucks 30 and 40 on the left and right are in theirs, respectively opening division, as the hydraulic cylinders 32 and 38 have retracted. At the same time, the welding nozzle 52 is in its fully inclined position, with the guide member 54 rests against the stop part 78, so that the welding head 12 is arranged at an angle to the vertical is, wherein the opening of the nozzle 52 is above the path of movement of the jig 16.

The operator arranges under the conditions just mentioned an elongated strip of material which has previously been deformed into a generally circular ring 22, so indicate that the edge portions 20 lie on the workpiece supports 28 and 34 and in contact with both longitudinal sides of teaching 16. If the strip of material to be welded is relatively thin and flexible, it is necessary to change the material in the form of a substantially round ring 22, because the operator can easily handle the material Bend to the edges 20 to rest on the jig 16

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bring. The faces 75 of the teaching facing away from one another are exactly parallel to one another, so that, according to FIG. 6, when the edges 20 of the workpiece are brought into contact with the faces 75, these edges also assume a parallel position. or if its edges can maintain their flat shape, the edge portions of the workpiece according to FIG. 6 are inclined towards the gauge 16 at an acute angle. If a control device, for example the foot switch 90 shown in FIG. 5, is actuated by hand, the hydraulic cylinders 32 and 38 are extended so that the clamping parts 30 and 40 are moved in the direction of the workpiece supports 28 and 34. Initially, the outer edges 76 of the clamping parts 30 and 40 are in contact with the edge portions of the workpiece in order to grasp them and set them at an angle to the jig 16 as shown in FIG. Then the cylinders 32 and 38 is further extended, the Etnspannteile 30 and 40 are further moved to bring about respective exchangeable clamping rails 77 for engaging the outer surface of the workpiece ¹ 22nd As the hydraulic cylinders move further, the clamping members 30 and 40 are caused to pivot about their outer edges 76 and to bend the edge portions of the workpiece so that the edges 20 are pressed down while they remain in firm contact with the surfaces 75 of the jig until the workpiece and the gauge reach the position shown in FIG. Here, the edges 20 of the workpiece sections are in firm contact with the surfaces 75, and the workpiece sections are arranged both in a common plane and at right angles to the surfaces 75 of the teaching. The edges 20 thus assume the correct position in which they extend parallel to one another with a high degree of accuracy. Only limited pivoting movements of the clamping parts 30 and 40 are required, and in the embodiment shown these movements are made possible by the fact that relatively loose fits at the knee

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lever assemblies are present which connect the cylinders 32 and 38 to the clamping parts 30 and 40.

Once the workpiece 22 has been firmly clamped using the clamping assemblies 24 and 26, the operator pulls the protective cover 80 down from its upper position. As soon as the protective cover reaches its lower position, it is automatically locked in its closed position by the device 82, and it actuates one Switch 92, which according to Pig. 5 controls the hydraulic actuator 46 so that the actuator is retracted to pull the gauge 16 according to FIG. 1 to the right. When doctrine 16 is in its extreme position approaches on the right side, a switch 94 is operated as shown in FIG. 5 to put the motor 70 into operation, whereupon the welding head 12 with the nozzle 52 according to FIG is advanced to the left. During the initial movement to the left, the guide member 54 disengages from the stop 78 brought so that the spring 74 the weld head 12 with the nozzle 52 in a generally vertical position pivots.

While the welding head 12 is in its vertical position, the guide part 54 is lifted from the switch 96, in order to cause the hydraulic actuating device 41 according to FIG. 2, the right clamping assembly 26 according to FIG move left to take the place of gauge 16. This horizontal movement of the right clamping assembly takes place over a distance that is greater than the thickness of the gauge 16 and thus also greater than the original distance between the edges 20 of the workpiece sections. Because the workpiece sections are originally in the same plane were arranged on both sides of the jig, the movement of the Einspännbaugruppe 26 initially leads to the fact that the edges 20 of the tire 22 are brought to bear against one another.

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Thereafter, the clamping assembly 26 is moved a further amount, with the associated workpiece section between the clamping part 40 and the support 34 moves. As a result, the edges 20 are pressed firmly against one another in order then to be welded to one another. To this To facilitate firm pressing of the edges 20, the hydraulic cylinder 38 exerts pressure on the right clamping part 40 which is less than the pressure that the hydraulic cylinder 32 exerts on the clamping part 30 on the left side brings up. For this purpose, it can be ensured that the cylinder 38 has a smaller inner diameter than the cylinder 32, or the hydraulic pressure supplied to the cylinder 58 can be limited accordingly. In practice it has the gauge 16 has a thickness of about 16 mm so that after removal of the gauge and after movement of the clamping assembly 26 covers this assembly a distance of about 16 mm to close the gap according to FIG. 8, which was previously by the Teaching was taken. The chuck assembly 26 then continues to move an additional distance of approximately 6.5 mm so that the portion of the workpiece held by the clamping assembly 26 will move that amount must before this clamping assembly is brought to a standstill, according to the full stroke of the cylinder 41 or according to FIG. 9, depending on the effectiveness of a stop 79. As soon as the factory tücbabs sections have reached this position, they are held tightly against each other, but no additional force is applied, to press the edges 20 against each other.

When the clamping assembly 26 according to FIG. 9 has reached its final position, it is between the relevant parts there is only such a distance that the welding nozzle 52 can be brought into the vicinity of the abutting edges 20 in order to start the welding process perform. With this arrangement, the consumable rails 77 support the workpiece edges, and also they absorb heat from the weld seam in order to transfer it to the

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To release clamping parts 30 and 40, so that a warping of the edges 20 is avoided in order to create a uniform ensure smooth weld seam.

While the left clamping assembly 24 is in its closed position moved, the movement of the welding head 12 is continued to the left until the nozzle 52 reaches the starting point of the The weld seam is reached, whereupon a limit switch 98 is actuated by the moving carriage 58, as shown in FIG to initiate the welding process. The welding head 12 is formed along the edges 20 formed by the abutting edges Seam moves, being aligned on a plane in which, according to FIG. 9, originally the left side surface 75 of teaching 16 found. After the welding seam has been completed, a further switch 100 is actuated by the carriage 58, to end the welding process. At the same time, the hydraulic cylinders 32 and 38 are retracted, to release the clamping assemblies 24 and 26, and the right clamping assembly 26 moves horizontally as shown in FIG To the right. During this latter movement, the protective cover or door 80 provided with the counterweight 81 is opened unlocked so that it can be brought up into its open position.

After completion of the welding process, the welding nozzle 52 moves along an additional distance, so that the Carriage 58 actuates a further limit switch 102, by means of which the motor 70 is reversed so that the welding head 12 is moved to the right again according to FIG. When reversing the direction of movement of the welding head, the hydraulic Cylinder 46 is actuated so that it is extended to advance the gauge 16 to the left as shown in FIG. Here occurs the left end of the gauge in the gap between the clamping assemblies 24 and 26, and the gauge detects the welded ring 22 in order to place it against the workpiece

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Eject supports 28 and 34. It comes at the same time provided with a cam surface left end of the gauge 16 to rest on the lower end of the guide member 54 to the The welding head 12 can be pivoted about the axis 56. Thereafter, the welding nozzle 52 is raised at an angle in a Moved position opposite the welding path to the right, wherein the guide part 54 cooperates with the top of the gauge 16. When the guide part 54 to bear against the stop 78 comes, the weld head 12 and guide member are pivoted an additional amount to the switch 96 to operate so that the motor 70 is switched off to prevent any further movement of the welding head 12 to the right impossible to do. When this operating state is reached the welded tire 22 has been ejected from the welding machine and the welding machine is ready for that pick up the next workpiece to be welded.

The electrical control circuit with those already mentioned Switches is in Fig. 5 in connection with schematic indications of the relevant parts of the welding machine shown.

The switch 90 is connected to a power source 104 and is operated by the operator with one foot, to close a circuit to a control device 91, which simultaneously actuates solenoid valves to the clamping cylinders 32 and 38 extend. That too Switch 92 connected to the power source 104 is closed in response to the closing of the protective cover 80 in order to close a solenoid valve associated with the cylinder 46 press so that the gauge 16 is withdrawn. When the jig actuating cylinder 46 is retracted, a switch 94 actuated to the circuit between the power source and a control device for the reversible motor to close so that the welding head 12 is moved. The switch 96 is normally inclined by the

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Welding nozzle 52 held open. The movement of the weld head 12 enables the nozzle 52 to be at such an altitude assume that the switch 96 closes the circuit between the power source 104 and a solenoid valve that associated with the cylinder 41 to retract this cylinder and the right clamping assembly 26 in its closed position opposite to the left clamping assembly 24 to bring. As the welding head continues to move forward 12, the switches 98, 100 and 102 are operated one after the other. Switch 98 is normally open, and so is the switch 100 connected to power source 104 remains normally closed; the welding head 12 becomes the system brought to the switch 98, this switch is closed to the circuit through the switch 100 to the Power source 104 to close, thereby starting the welding process is initiated. If the welding head comes to rest on the switch 100, this is opened to start the welding process to end and at the same time to release one of the locking device 82 associated electromagnet so that the Protective cover 80 moved up and in its opening division can be brought. At the same time causes the switch 100, which is also connected to the control device 91 and the Cylinder 41 is connected to cause cylinders 32 and 38 to simultaneously retract to the clamping assemblies 24 and 26, with the cylinder 41 extended to make the clamping assembly 26 level move and bring them into their open position. The further movement of the welding head 12 causes the Switch 102 is operated, which is connected to the motor control device, so that the motor is reversed; at the same time, the solenoid valve on the cylinder 46 is actuated so that the gauge 16 is extended. Is moving the welding head to the rear, it comes to rest on the switch 96 again; around the circuit between the power source 104 and to close the motor 70 so that the motor is stopped.

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The control circuit of Fig. 5 is so designed that when the clamping assemblies 24 and 26 by the operation of the pedal valve 90 have been brought into their closed position, the subsequent closing of the protective cover 80 and the switch 92 automatically causes each of the the remaining control switches 94 - 102 are operated one after the other, to automatically control the facilities concerned.

While hydraulic cylinders 32, 38, 41 and 46 are used in the preferred embodiment of the invention, they do it is of course also possible to use various other types of devices for generating a linear movement or To use hydraulic motors.

According to the above description, a welding machine has been created by the invention which makes it possible to automatically the mutually abutting edges of a workpiece, e.g. a ring made from a strip of material, to be welded, the edges being precisely aligned with one another with the aid of a gauge, the gauge according to is removed after aligning the edges so that the edges are brought into firm contact with one another for the purpose of welding can be. After finishing the welding process, the welded workpiece is ejected from the machine, and the machine is prepared to pick up the next workpiece; the movements of the parts concerned for holding, positioning, welding and ejecting the workpiece are in the correct chronological order brought about.

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Claims (15)

EXPECTATIONS 1. Machine for welding adjacent workpiece sections, characterized by being movable between first and second positions Teaching, clamping devices (24, 26) for each of the two workpiece sections (20), the clamping devices on opposite sides of the jig are arranged and operable to grasp the workpiece sections and place them in To keep plant on the doctrine when the doctrine is in its first position, a device (41) by means of which can move the clamping devices towards each other when the gauge is in its second position is located in order to bring the workpiece sections to rest against one another, a welding head (12), which is in the immediate Proximity of the abutting workpiece sections is movable, as well as a device (58) for moving the welding head such that the workpiece sections are welded together to produce a finished workpiece, wherein the clamping devices are releasable with respect to the workpiece sections and can be moved away from one another, wherein this movement takes place as a function of the fact that the welding head reaches the position in which the weld seam is completed, the doctrine being movable into its first position zv / ischen the clamping devices as soon as the gQ9833 / 1 060 Clamps have been removed from each other so that the gauge grips the workpiece and takes it out of the machine ejects, with a support part (28, 34) and a clamping part (30, 40) for each clamping device belong, wherein the clamping parts are movable with respect to the support parts, this on one side the jig arranged clamping part and the associated support part are movable to a workpiece portion to grasp, and these parts together with the workpiece section opposite the other clamping part, the other support part and the other workpiece portion are movable after the jig in its second Position has been brought, and wherein the support part and the clamping part on one side of the teaching grasp a workpiece section with a certain force, while the other clamping part and the other support part grasp the other workpiece section with a smaller force, so that a sliding movement of the other workpiece section compared to the clamping device is possible if the workpiece sections thereby to System are brought together that the clamping devices are moved towards each other. 2. Machine according to claim 1, characterized by two pressure medium-actuated cylinders (32, 38) which the clamping devices (30, 40) are assigned, the one cylinder exerting a force on one of the clamping parts that is smaller is than the force applied to the other chuck to cause a sliding movement of a workpiece portion (20) to enable between the one clamping part (40) and the associated support part (34). 3. Machine according to claim 1, characterized in that the welding head (12) is movable along a path which in in the immediate vicinity of the workpiece sections (20) if the welding head between 809833/1060 2806195 its first and its second position is moved, and that the welding head can be brought into an elevated position above the movement path of the gauge (16) and after completion of the welding process can be moved from the second to the first position. 4. Machine according to claim 3 »characterized in that a guide part (54) belongs to the welding head (12) which can be brought to bear on the teaching (16) if the Gauge is in its first position to keep the weld head in its raised position while it comes out of the second is brought into the first position. 5. Machine according to claim 4, characterized in that the welding head (12) can be moved from an elevated position into a welding position, and that this movement is in Dependent on it is brought about that the teaching (16) is brought into its second position. 6. Machine according to claim 1, characterized in that a protective cover (80) is present which, between a Open position and a closed position can be moved in order to protect an operator against the welding head (12), while this executes its welding movement, and that a device (82) is present which is dependent on the Movement of the protective cover in its closed position is actuatable to cause the jig (16) in its second Position is brought. 7. Machine according to claim 6, characterized in that the protective cover (80) in its open position as a function thereof it can be brought about that the welding head (12) reaches the position in which the welding process ends is. 8. Machine for welding adjacent workpiece sections, marked by a 809833/1080 between a first and a second position movable jig (16), two devices (24, 26) for clamping the Workpiece sections (20) arranged on opposite sides of the jig, these devices being operable are in order to detect surfaces of the workpiece sections facing them and the workpiece sections in contact with the Teaching so firmly that they are in alignment with one another on a common plane when the teaching is in its first position is, the gauge has a predetermined width, further by means (41) by means of which the clamping devices are moved towards each other when the gauge is in the second position, in order to move the workpiece sections towards one another, wherein the clamping devices can be moved along a path, which is greater than the thickness of the gauge in order to bring the workpiece sections into firm contact with one another, a welding head (12), which can be moved in the immediate vicinity of the workpiece sections resting against one another, and a device (46) for moving the welding head in such a way that the workpiece sections are welded together so that a finished workpiece is created. 9. Haschine according to claim 8, characterized in that it is possible for one of the workpiece sections (20) to be welded to face the associated clamping device (26) to move when a relative movement of the clamping devices towards each other is brought about. 10. Haschine according to claim 8, characterized in that the clamping device (24) on one side of the gauge (16) maintains its position, while the other clamping device (26) is moved towards them. 11. Haschine according to claim 8, characterized in that the clamping device arranged on one side of the gauge (16) 809833/1080 Means (26) is suitable to grasp the associated workpiece section (20) with a predetermined force, the is smaller than the force with which the clamping device (24) on the other side of the teaching the associated Workpiece section detected. 12. Machine according to claim 8, characterized in that the clamping device (26) on one side of the jig (16) can be moved into a predetermined position, the latter Movement takes place along a distance which is greater than the thickness of the gauge, and that the two clamping devices be held firmly in place during the welding process. 13. Machine according to claim 8, characterized in that the clamping devices (24, 26) are releasable with respect to the workpiece sections (20) and can be moved away from one another, these movements are brought about after the end of the welding process, and that the gauge (16) from the second position is movable into the first position between the clamping devices in order to grasp the finished workpiece and to move it relative to the chucks so that it is ejected from the machine. 14. Machine according to claim 8, characterized in that a support part for each of the two clamping devices (24, 26) (28, 34) and a clamping part (30, 40), with the clamping parts opposite the support parts are movable, and that the workpiece sections (20) are initially brought to bear against the gauge (16) that they extend at an angle thereto, whereupon the movement of the clamping parts towards the workpiece sections leads to the application of a force which has a component directed at the jig, through which the workpiece sections be brought into permanent attachment to the teaching. 809833/1060 2506185 15. Machine according to claim 8, characterized in that the clamping devices (24, 26) are operable to initially grasp the workpiece sections (20) at points and to clamp, which are offset from the edges of the workpiece sections, while these edges on the jig (16), the workpiece sections opposite the side surfaces (75) facing them each below the teaching diverge at an acute angle, and that the clamping devices can be actuated to thereafter the workpiece sections at second points, which are closely adjacent to the edges of the workpiece sections, around the workpiece sections to bring from their inclined position against the side surfaces of the teaching in a position in which they are in a common plane. 809833/1060