KR19980085251A - Processing Balance - Google Patents

Abstract

A trolley body, a driving means, a wheel freely disposed with respect to the trolley body, rotation transmission means for transmitting the rotation generated by the driving means to the wheel, and a traveling surface disposed on the trolley body. And a permanent magnet employing an operating position for generating a suction force, a retracted position retracted from the operating position, a lever connected to the permanent magnet, a processing torch provided in the bogie body, and the bogie body. It has a handle that is fixed to it. In this case, when the work cart is placed on the running surface and the lever is slightly rotated, a suction force is generated between the permanent magnet and the running surface, and the permanent magnet falls down at once and adopts an operating position. Thus, while the permanent magnet adopts the operating position, the movable cart is pressed against the running surface by the suction force, so that sufficient friction force can be generated between each wheel and the running surface. Therefore, the traction force can be sufficiently generated when driving the processing trolley. Thus, when the machining is finished and the operator operates the lever to rotate the permanent magnet and puts it in the retracted position, the suction force generated between the permanent magnet and the running surface is eliminated, so that the processing cart can be lifted with a small force. .

Description

Processing Balance

1 is a perspective view of a welding bogie in an embodiment of the present invention.

2 is a perspective bottom view of a welding trolley in an embodiment of the present invention.

3 is an enlarged view of a permanent magnet in the embodiment of the present invention,

4 is a view for explaining the function of the lever having a handle in the embodiment of the present invention.

* Description of the symbols for the main parts of the drawings *

10: welding cart 11: bogie body

12: permanent magnet 13a, 13b: rotating shaft

14: lever 15: coil spring

17: motor 28: front and rear positioning device

29: up and down position adjustment device 30: angle adjustment bracket

32: welding torch 51: magnet chamber

52: right driving bacteria chamber 53: left driving bacteria chamber

57: reducer 59: mounting condition adjusting device

77: the handle

[Background of invention]

[Field of Invention]

The present invention, processing cart Iii).

[Related Technologies]

Conventionally, when performing a fillet weld, butt weld, or the like in a welded joint, a welding bogie as a processing bogie is disposed on a horizontal plate as a running surface, and the weld bogie is used as a vertical plate. To drive along. To this end, the welding trolley is provided with a motor, and can be driven by driving the motor to rotate the drive wheels. Moreover, the imitation roller is arrange | positioned, and it is possible to perform welding line imitation automatically by rotating this imitation roller against a vertical board | plate material.

By the way, when welding is performed using the said welding trolley, it is necessary to set a welding trolley at a welding start point, or to remove from a welding end point. Thus, in order to facilitate the transport of the welding trolley, a feeding device for supplying a wire as a welding material to the welding torch is arranged in a place separate from the welding trolley, and the wire is torch cable. It supplies to the welding torch through.

In this case, since the welding torch cable follows the welding bogie while the welding bogie is running, the welding line imitation cannot be reliably performed unless the traction force for pulling the welding torch cable is sufficient.

Thus, in order to increase the traction force, there is provided a welding bogie in which drive wheels are formed by electromagnets or permanent magnets. Moreover, the welding trolley which arrange | positions an electromagnet or a permanent magnet at the bottom of a welding trolley | bogie, and runs at intervals between an electromagnet or a permanent magnet and a horizontal board | plate material is provided.

However, in the conventional welding trolley, in the case of the welding trolley in which the driving wheels are formed of electromagnets or permanent magnets, the friction coefficient of the surface of the driving wheels is small, so that a sufficient friction force cannot be generated between the driving wheels and the horizontal plate material. If foreign matter is caught between the driving wheel and the horizontal plate member, the welding substitute will be turned, and the welding line will not be imitated, and welding will be impossible.

On the other hand, in the case of a welding trolley in which an electromagnet or a permanent magnet is disposed at the bottom, the driving wheel can be formed of a rubber material, so that not only a sufficient friction force can be generated between the driving wheel and the horizontal plate, but also the driving wheel and the horizontal plate and Even if foreign matter gets caught in the gap, the welding truck can be stabilized and run, and welding can be performed.

However, the space between the electromagnets or permanent magnets and the horizontal plate is spaced, so that the suction force by the electromagnets or permanent magnets must be so large.

Therefore, in the case of using an electromagnet, if the suction force is to be increased, the size of the electromagnet becomes large, and the welding bogie becomes large.

In addition, if the distance between the electromagnet or permanent magnet and the horizontal plate member is made small in order to increase the suction force, for example, when the welding bead is formed on the horizontal plate member, the welding bogie cannot be driven safely.

In contrast, when the permanent magnet is used, the permanent magnet has a large suction force against its own weight, so the size of the permanent magnet does not need to be increased. However, when the welding is finished, a large force is required when the welding bogie is removed from the end point of welding. Handleability worsens.

Thus, the permanent magnets adopt an operating position close to the horizontal plate member and a retracted position away from the horizontal plate member, and at the end of welding, operate the lever using the principle of lever to evacuate the permanent magnet. It is possible to remove the welding cart with a small force.

However, in order to put the permanent magnet in the retracted position, it is necessary to operate the lever against the suction force, which not only increases the operating force of the lever but also enlarges the mechanism of the lever. In addition, in order to reduce the force required for removing the weld bogie, the retracted position must be set at a position sufficiently far from the horizontal plate material, so that the dimensions of the weld bogie become large.

[Summary of invention]

The present invention solves the problems of the conventional processing trolley, and can not only generate a sufficient friction force between the driving wheel and the running surface, but also stably run even if foreign matter is caught between the driving wheel and the running surface. The present invention aims to provide a processing trolley which can be removed with a small force and has a small dimension.

To this end, according to the present invention, in the processing trolley, a rotation body for transmitting the bogie body, the driving means, a wheel freely disposed with respect to the bogie body, and the rotation generated by the driving means to the wheels. A permanent magnet disposed on the vehicle body, the permanent magnet employing an operating position for generating a suction force between the running surface, a retracted position withdrawn from the operating position, a lever connected to the permanent magnet, and And a processing torch mounted on the balance body, and a handle fixed to the balance body.

In this case, when the processing trolley is placed on the running surface and the lever is slightly rotated, a suction force is generated between the permanent magnet and the running surface, and the permanent magnet falls down at once and adopts an operating position. Thus, while the permanent magnet adopts the operating position, the processing cart is pressed against the running surface by the suction force, so that sufficient friction force can be generated between each wheel and the running surface.

Therefore, the traction force can be sufficiently generated when driving the processing trolley.

Thus, when the processing is finished and the operator operates the lever to place the permanent magnet in the retracted position, the suction force generated by the research magnet between the running surface is eliminated, and thus the processing cart can be lifted with a small force.

In another bogie of the present invention, there is again a spring for applying a force to direct the permanent magnet to the retracted position.

In this case, if the processing trolley is placed on the running surface and the lever is rotated slightly, suction force is generated between the permanent magnet and the running surface, and the permanent magnet falls down quickly against the spring force by the spring, and adopts the operating position. do. Thus, while the permanent magnet adopts the operating position, the processing trolley is pressed against the running surface by the suction force, so that sufficient friction force can be generated between each wheel and the running surface.

Therefore, the traction force can be sufficiently generated when driving the processing trolley.

Thus, the machining ends, and when the worker grabs the handle and tilts it, the movable trolley tilts in the same direction and tilts in the same direction as the permanent magnet in the operating position. As a result, the suction force generated by the permanent magnet between the running surface is small, so that the permanent magnet adopts the retracted position at once by the spring force by the spring.

Thus, at this time, the suction force generated by the permanent magnet between the running surface is eliminated, so that the processing cart can be lifted with a small force.

In still another processing trolley of the present invention, the permanent magnet is freely oscillated, parallel to the running surface in the operating position, and nonparallel to the running surface in the retracted position.

In this case, the suction force can be reduced only by rotating the permanent magnet.

In another processing trolley of the present invention, the processing torch is again a welding torch.

Specific Example

EMBODIMENT OF THE INVENTION Hereinafter, embodiment of this invention is described in detail, referring drawings.

1 is a perspective view of a welding trolley in an embodiment of the present invention, and FIG. 2 is a perspective bottom view of a welding trolley in an embodiment of the present invention, and FIG. 3 is an enlarged view of a permanent magnet in an embodiment of the present invention.

In the drawings, reference numeral 10 denotes a welding bogie as a processing bogie which causes a traveling surface not shown at the time of welding, for example, to run on the horizontal plate in the direction of the arrow A. FIG. 11 is a balance body, and this balance body 11 is an aluminum body. The upper wall 11a, the front wall 11b, the rear wall 11c, the right 11d arrange | positioned at the right side with respect to a travel direction, and the left wall 11e arrange | positioned at the left side with respect to a travel direction are formed.

Thus, below the upper wall 11a, the front wall 11b, the rear wall 11c, the right wall 11d and the left wall 11e seat the seating compartment 51, the right wall 11d the right driving wheel room 52, the front wall 11b, the rear wall 11c and the left wall 11e. Drive wheel accommodation chamber 53 is formed, respectively.

The permanent magnet 12 is disposed in the magnet housing chamber 51. The permanent magnet 12 is freely supported on the brackets 16a and 16b suspended from the rear surface of the upper wall 11a, and adopts the retracted position indicated by the solid line in FIG. 2 and the operating position indicated by the broken line.

To this end, the front end and the rear end of the permanent magnet 12, the rotation shaft 13a, 13b is formed to protrude respectively. Thus, the rotating shaft 13a extends forward through the bracket 16a and the front wall 11b and is fixed to the lever 14 outside the magnet housing chamber 51. The rotating shaft 13b extends rearward through the bracket 16b.

For example, a first stopper (not shown) is provided on the right wall 11d so that the permanent magnet 12 does not fall to the right wall 11d side more than the retracted position. In addition, the second stopper 55 is provided on the left wall 11e so that the permanent magnet 12 does not incline toward the horizontal plate side more than the operating position, and extends in the horizontal direction.

Thus, a spring, for example, a coil spring 15, is disposed between the permanent magnet 12 and the bracket 16b around the rotating shaft 13b to apply a force to roll the permanent magnet 12 toward the retracted position by the coil spring 15. .

Therefore, when the lever 14 is rotated by a predetermined angle in the direction of the arrow B so that the permanent magnet 12 is inclined at the same angle, the permanent magnet 12 is driven by the coil spring 15 by its own suction force generated between the horizontal plate and the like. It resists the spring force and falls to 90 ° at a time, stops by reaching the second stopper 55, and adopts an operating position. In the meantime, since the lever 14 rotates to 90 degrees following the permanent magnet 12, the force for operating the lever 14 becomes unnecessary.

In this manner, since the permanent magnet 12 can be placed in the operating position only by rotating the lever 14 at a predetermined angle with a small force, the operability of the welding trolley 10 can be improved.

On the other hand, when the welding trolley 10 is not placed on the horizontal board member, the permanent magnet 12 does not generate a suction force between the horizontal board member. Therefore, even if the lever 14 is rotated by 90 ° and the permanent magnet 12 is in the operating position, the permanent magnet 12 rises at once by the spring force of the coil spring 15, and adopts the retracted position when the force for operating the lever 14 is released. . Since the lever 14 rotates following the permanent magnet 12, the force for operating the lever 14 is unnecessary.

By the way, the permanent magnet 12 is formed by two magnetic poles 12a, 12b and yoke 12c, and the magnetic poles 12a and 12b are exposed on one side of the permanent magnet 12, and in other cases, surrounded by the yoke 12c. do. Therefore, the magnetic flux is connected between the magnetic poles 12a and 12b so that the magnetic flux is formed only on the side where the magnetic poles 12a and 12b are exposed.

In this case, when the permanent magnet 12 is placed in the operating position, a magnetic path is formed between the magnetic poles 12a and 12b and the horizontal plate, and the leakage magnetic flux can be almost eliminated, so that the suction force by the permanent magnet 12 can be increased. . Incidentally, when the permanent magnet 12 is tilted, the magnetic path formed between the magnetic poles 12a, 12b and the horizontal plate member becomes smaller so that the suction force by the permanent magnet 12 is reduced. Thus, when the permanent magnet 12 is placed in the retracted position, almost no magnetic path is formed between the magnetic poles 12a, 12b and the horizontal plate, and no suction force by the permanent magnet 12 occurs.

In the permanent magnet 12, the depth can be increased by increasing the distance between the magnetic poles 12a and 12b, so that the suction force by the permanent magnet 12 can be increased by that much.

At the rear end of the balance body 11, the reducer 57 is disposed on the upper wall 11a, and the motor 17 as the driving means is disposed on the reducer 57, and the rotation generated by driving the motor 17 is decelerated by the reducer 57. Is output to the output shaft 57a of the reducer 57. The drive side bevel gear 18a is fixed to this output shaft 57a, and this drive side bevel gear 18a and driven side bevel gear 18b are meshed, and the rear wheel drive shaft 19a is fixed to this driven side bevel gear 18b again. Thus, the dimension of the drive side bevel gear 18a is set smaller than that of the driven side bevel gear 18b. Accordingly, the rotation output to the output shaft 57a can be further decelerated by the driving side bevel gear 18a and the driven side bevel gear 18b to be transmitted to the rear wheel drive shaft 19a.

By the way, this rear wheel drive shaft 19a is rotatably supported with respect to the truck body 11 through a bearing (not shown) at the rear end of the main body 11, and the right end of the rear wheel drive shaft 19a extends through the right wall 11d, It is fixed to the wheel 21a at the right rear side from the outside of the magnet housing chamber 51. The left end of the rear wheel drive shaft 19a extends through the left wall 11e and is fixed to the left wheel 21b on the outside of the magnet housing chamber 51.

Thus, the vehicle body 11 is driven in a four-wheel drive system, and the rotation transmitted to the rear wheel drive shaft 19a can be transmitted to the wheel 21c in the right front and the wheel 21d in the left front, respectively. To this end, the front wheel drive shaft 19b is freely supported by the front end of the balance body 1 via a bearing (not shown), with respect to the body main body 11, and the right end of the front wheel drive shaft 19b extends through the right wall 11d, It is fixed to the wheel 21c outside the magnet housing chamber 51. The left end of the front wheel drive shaft 19b extends through the left wall 11e and is fixed to the wheel 21d from the outside of the magnet housing chamber 51.

Thus, the sprocket 22a is fixed to the rear wheel drive shaft 19a, and the sprocket 22b is fixed to the front wheel drive shaft 19b, respectively, and the chain 24 is wound around both sprockets 22a and 22b.

In this way, the rotation generated by driving the motor 17 is transmitted through a rotation transmission means comprising drive side bevel gear 18a, driven side bevel gear 18b, rear wheel drive side 19a, sprockets 22a, 22b, chain 24 and front wheel drive shaft 19b. It is transmitted to each wheel 21a-21d, and can drive the welding trolley 10. In this case, each wheel 21a-21d becomes a drive wheel. Then, only the wheels 21a and 21b or the wheels 21c and 21d may be driven.

Thus, since each of the wheels 21a to 21d is formed of a rubber material, not only can the wheels 21a to 21d be generated with sufficient friction force, but also the wheels 21a to 21d and the horizontal plate material. Even if foreign matter gets caught between the two, the welding trolley 10 can be stabilized and run.

In this case, if the distance between the permanent magnet 12 and the horizontal plate is set to about 7 [m / m], the suction force generated by the permanent magnet 12 is about 10 [kg], and the weight of the welding cart 10 is about 8 [kg]. ], A force of about 18 [kg] can be applied between the wheels 21a to 21d and the horizontal plate.

Thus, the welding torch 32 as the processing torch is disposed at the center of the balance body 11 by tilting the right wall 11d side up and the left wall 11e side down so that welding can be carried out while driving the welding truck 10. The welding torch 32 is fixed to the valve state adjusting device 59 while tightening the torch clamp (torch holder) 31, and a wire 32a serving as a welding material protrudes from the tip. A welding torch cable 32b is connected to the rear end of the welding torch 32 so that the wire 32a can be supplied from a feeding device not shown through the welding torch cable 32b.

In the torch clamp 31, the pipe portion 32c of the welding torch 32 is bent and tightened, whereby the welding torch 32 itself can be prevented from rotating when the welding torch cable 32b is towed.

Thus, the mounting state adjusting device 59 is for accurately placing the tip of the welding torch 32 at the welding position, and the forward and backward position for moving the tip of the welding torch 32 back and forth (right and left with respect to the traveling direction of the welding carriage 10). And an adjusting device 28, an up and down position adjusting device 29 for moving the tip of the welding torch 32 up and down, and an angle adjusting bracket 30 for changing the inclination of the welding torch 32.

The front-rear position adjusting device 28 is made of a handle 28a and a moving block 28b. In this moving block 28b, a trapezoidal screw (not shown) rotated by the handle 28a corresponds to the trapezoidal screw on the surface of the upper wall 11a. Each rack is formed, which is not shown. Therefore, by moving the said handle 28a, the said moving block 28b can be moved to arrow C direction (left-right with respect to the advancing direction of the welding trolley | bogie 10).

The vertical position adjusting device 29 is a handle 29a, a moving block 29b, and a fixed block 29c fixed to the moving block 28b of the front and rear position adjusting device 28, and in the moving block 29b, the handle 29a is used. On the surface of the fixed block 29c, a rack (not shown) corresponding to the trapezoidal screw is formed on the surface of the fixed block 29c to be rotated. Therefore, by moving the knob 29a, the movable block 29b can be moved in the direction D (up and down direction).

In addition, the angle adjustment bracket 30 is a rectangular adjustment plate 30a disposed in parallel with the moving block 29b, a screw 30b for fixing the adjustment plate 30a to the moving block 29b at the four corners of the adjustment plate 30a, and the side of the moving block 29b. And an onboard adjustment plate not shown. Therefore, the angle of the welding torch 32 can be adjusted by rotating this adjustment screw.

Moreover, in the rear end of the said trolley | bogie main body 11, the control box 33 is fixed on the upper wall 11a adjacent to the said reducer 57 and the motor 17. As shown in FIG. In this control box 33, various handles 33a are disposed. By operating the handles 33a, it is possible to switch the running and stopping of the welding trolley 10, to change the traveling speed, and to change the start and end of welding. have.

Thus, in order to travel along the vertical plate not shown in the welding bogie 10, a pair of arms 23a, 23b are projected and disposed in the left direction of the welding bogie 10, and the imitation rollers 24a, 24b are respectively disposed on the arms 23a, 23b. Rotation is supported freely. Therefore, while the welding trolley 10 is driven, the welding line imitation can be automatically performed by rotating the imitation rollers 24a and 24b against the vertical plate member.

Moreover, since each arm 23a, 23b is fixed to the front wall 11b and the rear wall 11c by the bolt 62, respectively, and adjusts the position with respect to the trolley | bogie main body 11 of each imitation roller 24a, 24b, it is possible to adjust the amount of protrusion. . For this purpose, a long groove 61 is formed at the rear end of each of the arms 23a and 23b, and a bolt 62 is inserted into the long groove 61 so as to loosen the bolt 62 so that the arms 23a and 23b can be moved in the horizontal direction.

And in this embodiment, although each arm 23a, 23b can be moved only in a horizontal direction, instead of the said long groove 61, for example, using the "H" type groove | channel, each arm 23a, 23b can be moved not only in the horizontal direction but also in the vertical direction.

By the way, when the welding trolley | bogie 10 of the said structure is run along a vertical board | plate material, and it welds by the welding torch 32, the metal melted by welding will scatter.

Thus, if the scattered metal is solidified and enters the left drive wheel accommodation chamber 53 and is pinched between the wheels 21a to 21d and the horizontal plate, the welding bogie 10 can not pivot and weld line imitation cannot be performed. It is done.

Thus, a skirt 72 (shown only in FIG. 1 for the convenience of explanation) is disposed on the left side of the left drive wheel accommodation chamber 53, and the left drive wheel accommodation chamber 53 is covered by this skirt 72. In addition, the skirt 72 is provided so as to be movable up and down with respect to the bogie body 11, so that the lower end can always be slid to the horizontal plate while the welding bogie is traveling in the tenth position.

In the case where weld beads and the like are formed on the horizontal plate, at least the front lower end 72a of the skirt 72 is bent so that the weld beads and the like can easily ride over.

Thus, the stop switch 75 is disposed on the front wall 11b so that the welding cart 10 can be stopped when the welding cart 10 reaches the welding end point. This stop switch 75 has a pressing part 75a which always applies a force forward by a spring or the like not shown. Moreover, at the said welding end point, the stopper which is not shown in figure at the position corresponding to the said press part 75a is arrange | positioned previously.

Therefore, when the welding trolley 10 reaches the welding end point, the pressing portion 75a is pushed back against the spring force of the spring by the stopper, and the stop switch 75 is turned off. As a result, the motor 17 is stopped and the welding cart 10 is stopped.

The handle 77 is attached to the rear wall 11c of the balance body 11. The handle 77 is formed from a standing portion 77a, which is erected vertically from the rear wall 11c, and a handle portion 77 which protrudes forward from the upper end of the standing portion 77a and is fixed, and the handle portion 77b extends from the center portion to the front of the body body 11. .

The handle 77 has a function of a handle for carrying the welding trolley 10 by holding the handle 77b after the completion of welding, and a lever for placing the permanent magnet 12 in the retracted position.

Next, the function of the lever of the handle 77 will be described.

4 is a view for explaining the function of the lever of the handle in the embodiment of the present invention.

In the figure, 10 is a welding bogie, 11 is a bogie body, 11a is an upper wall of this bogie body 11, 11d is a right wall of the bogie body 11, 11e is a left wall of the bogie body 11, 12 is a permanent magnet, 13b is a rotating shaft, 15 is a coil spring, 21a is a right rear wheel, 21b is a left rear wheel, 55 is a second stopper, 77 is a handle, 77a is a standing part of the handle 77, 77b is a handle part of the handle 77, 81 is a horizontal plate .

As described above, when the welding trolley 10 is traveling on the horizontal plate 81, the permanent magnet 12 resists the spring force by the coil spring 15 by its own suction force generated between the horizontal plate 81. To adopt the operating position.

Thus, while the permanent magnet 12 adopts the operating position, the welding bogie 10 is pressed against the horizontal plate 81 by the suction force, so that a sufficient frictional force is generated between the wheels 21a to 21d (FIG. 2) and the horizontal plate 81. Can be generated.

Therefore, when the welding trolley 10 is driven, the welding torch cable 32b (FIG. 1) moves following the welding trolley 10, but a sufficient pulling force for pulling the welding torch cable 32b can be generated. I can do it.

Therefore, when welding is complete | finished and an operator grasps the said handle part 77b and inclines the handle 77 to arrow E direction, for example, about 5 degrees, the welding trolley 10 will be the most right side of the wheel 21a, It is inclined in the same direction about the lower end point P1, and the permanent magnet 12 in the operating position is inclined in the same direction, so that the permanent magnet 12 degrees and the horizontal plate 81 are non-parallel.

As a result, the suction force generated by the permanent magnet 12 between the horizontal plate member 81 becomes small, so that the permanent magnet 12 is instantaneously generated by the spring force by the coil spring 15, and adopts the retracted position. In the meantime, since the lever 14 rotates following the permanent magnet 12, the force for operating the lever 14 is unnecessary. The permanent magnet 12 can be rotated by operating the lever 14 without tilting the handle 77.

In this case, when the distance between the point P1 and the center P2 of the handle 77b is AL and the distance between the point P1 and the point P3 corresponding to the center of the permanent magnet 12 on the horizontal plate 81 is BL, The distance AL is about three times the distance BL. Therefore, the welding trolley 10 can be tilted only by applying a force 1/3 of the suction force generated by the permanent magnet 12 to the handle portion 77b, and the permanent magnet 12 can be placed in the retracted position.

In this embodiment, although the operator inclines the handle 77 in the direction of arrow E, the permanent magnet 12 is placed in the retracted position. However, the operator holds the handle 77b and handles in the direction opposite to the direction of arrow E. The permanent magnet 12 may be placed in the retracted position by tilting 77.

Although the welding trolley 10 is used as the processing trolley and a welding torch 32 is mounted on the welding trolley 10 for welding, a gas cutting trolley is used as the processing trolley and a gas cutting torch is mounted on the gas cutting trolley. Gas cutting may be performed.

Moreover, although the processing trolley is made to drive on a horizontal board material, it can also drive on a vertical board material.

In addition, this invention is not limited to the said embodiment, It is possible to make various changes based on the meaning of this invention, These are not excluded from the scope of this invention.

Claims (4)

(a) the balance body, (b) drive means, (c) a wheel which is freely rotated with respect to the bogie body, (d) rotation transfer means for transmitting the rotation generated by the drive means to the wheel; (e) a permanent magnet disposed on the balance body and employing an operating position for generating a suction force between the running surface, and a retracted position withdrawn from the operating position; (f) a lever connected to the permanent magnet, (g) a processing torch installed in the balance body; (h) the processing bogie, characterized in that it has a handle fixed to the bogie body. The processing cart of Claim 1 which has a spring which applies the force which directs the said permanent magnet to a retracted position. The processing cart according to claim 1, wherein the permanent magnet is freely oscillated, parallel to the running surface in the operating position, and nonparallel to the running surface in the retracted position. The processing cart according to claim 1, wherein the movable torch is a welding torch.