JPS6021031B2 - resistance seam welding machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention has two electrode rollers arranged one above the other, and the welding current is transmitted from a fixed position to a rotating part with respect to these electrode rollers. guided by a welding device, one of the rollers being supported by an oscillating arm, and further comprising a transfer device for advancing the workpiece to be welded relative to the ferrule roller. Regarding resistance seam welding machines.

In known resistance seam welding machines, the welding current flows from a stator forming a stationary part to a rotor forming a rotating part rotatably supported on this stator between these stators and the rotor. The conduction is carried out by a conductive fluid, preferably mercury, within the gap.

In this case, the electrode rollers consisting of stator and rotor together with the welding current transmission device form a structural unit. For example, the side plate (Zarge) from which the socket is made has two electrode rollers arranged one above the other forming a longitudinal weld seam, and one electrode roller has to be placed inside the side plate. In resistance seam welding machines, for reasons of location, there is no possibility of current transfer from the electrode roller to the rotor via the stator and the conductive fluid, which are placed at the end of one conductive arm. There is no possibility of current transmission.

In order to adapt it to the purpose, a second electrode roller attached to the outside of the workpiece, e.g. the side plate, is formed inside the workpiece in the same way as the aforementioned electrode roller, i.e. the electrode roller and the electrode roller are simply welded below. The device for transmitting current from a stationary part to a rotating part, such as a current-rotation transmission device, forms a structural unit. The last-mentioned electrode roller is arranged at the end of the swingable arm and is swung outwards when the workpiece to be welded is inserted between the two electrode rollers. be made so that it can be done.

In this case, the tensioning arm is swingably arranged on the machine platform so that it can move up and down in a plane extending in a direction that coincides with the direction of advancement of the workpiece. The electrode roller, which forms a unit with the welding current rotation transmission device, has a relatively large weight acting on the end of the overhanging arm. Furthermore, the electrode roller is pressed against the workpiece, for example by a spring, in order to provide the necessary welding force. A special feature is the electrode roller which is arranged for an upward oscillating movement when inserting the workpiece between the two electrode rollers, so that due to the large mass of the electrode roller 50% of the welding force is
It is necessary to generate a large acceleration force exceeding . As the forward speed of the workpiece increases, this relationship becomes even more problematic. Furthermore, when inserting the workpiece between the electrode rollers, grooves or notches are created in the initial part of the workpiece, which can lead to significant defects in the subsequent machining of the workpiece or to the production of defective products. ). As efforts are constantly being made to increase the forward speed, increasing difficulties arise in connection with the above-mentioned problems. It is therefore an object of the invention to reduce the mass of the assembly consisting of the arm and the electrode roller and to eliminate all the disadvantages mentioned above.

In order to solve the above-mentioned object, the present invention provides a resistance seam welding machine of the type mentioned at the outset, in which an electrode roller capable of oscillating movement is arranged on an overhanging arm extending transversely to the direction of advancement. a housing in which the overhanging arm is swingably supported in the machine platform about a swing axis spaced apart from the electrode roller and extending transversely to the axis of rotation thereof, and rotatable within the housing; a shaft supported and supporting an electrode roller at its free end, and such that the housing forms a stationary part of the aforementioned current-carrying bag and said shaft forms a rotating part; It is characterized by being The distance of the electrode roller from the swing axis of the overhanging arm is
Preferably it is substantially greater than the distance of the end of the housing towards the electrode roller from the aforementioned pivot axis. Due to this arrangement and configuration of the projecting arm, the welding current rotational transmission device of the electrode roller, which together with the electrode roller forms a structural unit in the above-mentioned known machines of this kind, is projecting outwards. It is directly supported on the machine table as a mass body made equal to the swing axis of the overhanging arm, and thereby the mass of the electrode roller that performs one vertical movement is substantially reduced.

The movement of the flange arm thus occurs not in a plane oriented in the same direction as the forward direction, but in a plane lying transversely to the forward direction. . The welding current rotation transmission device of the electrode lo-fu, which is the main mass, is extended from the electrode roller with respect to the swing axis of the overhanging arm, which is spaced apart from the electrode roller. Further configurations of the electrode rollers allow the electrode rollers to be made hollow according to the purpose, thereby further reducing the mass. Furthermore, in other configurations suitable for the purpose, an electrode roller is disposed at the free end, a rattan rotatably supported by the housing, an overhanging arm capable of swinging movement together with the housing, and a welding current rotation transmission device. This further helps to reduce mass if the shaft itself is also hollow. In this case, the transmission of current takes place from the closed housing to the shaft via a conductive fluid, such as mercury, which is present in the annular gap between the housing and the shaft for current conduction, and to the electrode loaf. . Additionally, the hollow shaft allows for the inclusion of separate supply and return channels for cold soot for cooling the electrode rollers in configurations suitable for still other purposes.

To dissipate the heat generated during resistance welding from the electrode roller, cooling water is passed through an axial hole in the stator of the smoke electrode roller containing mercury between the stator and the roller. This was done with extremely low efficiency. That is, it has been impossible to directly cool the rollers with cooling water. However, if the hollow electrode roller is placed at the end of the hollow shaft containing the refrigerant supply and return channels, the area around the electrode roller can also be very effectively cooled from inside the hollow loaf. be. The arrangement of the welding current rotation transmitting device in an overhanging manner relative to the swinging shaft of the overhanging arm also makes it possible to drive the electrode roller through the hollow shaft without any play.

To drive the electrode rollers without play, a computer control device is provided for controlling the speed of forward movement of the workpiece by the transfer device and the welding rollers.
In this case, the speed of the drive motor of the transport device is controlled by the computer in such a way that the first welding point is in each case at an adjustable distance from the front edge of the workpiece, e.g. the side plate, and the electrodes which propel the workpiece further The speed of the roller drive motors is controlled by the computer so that each final weld point is at an adjustable distance from the trailing edge of the workpiece. Such speed control is such that one of the weld points produced by each half-wave of the welding current comes directly to the leading or trailing edge of the workpiece, and the material in that area burns and the workpiece The purpose is to prevent excessive processing and surprising results. Further details and advantages of the invention emerge from the following description and the drawings, in which embodiments of the subject matter of the invention are shown by way of example only.

1 and 2, a resistance seam welding machine is shown with a housing 11, a hollow shaft 12 rotatably supported within the housing, and an overhanging arm consisting of an electrode roller 13 disposed at the end of the hollow ball. 10 and also the drive device for the drive of the hollow shaft with electrode rollers are shown.

The direction of advance of the workpiece, which is not shown in the drawing, is indicated by arrow B. Electrode roller 13 and forward direction B
Although the angle Q between the electrode rollers is shown exaggerated, such a slightly oblique positioning of the electrode rollers may be useful when welding a workpiece, such as the end of the side plate 15 as shown in FIG. From the green part shown in FIG. 1, the side plate 15 according to FIG.
The longitudinal edges of the upper electrode roller 1 are to be welded.
3 and the electrode loaf 17 supported in the welding arm 16 below this to ensure that they are kept in an overlapping relationship. From FIGS. 1 and 2, a housing 1 forming an overhanging arm 10 together with a hollow shaft 12
1 has a machine base 19 mounted so as to be swingable around a swing shaft 18 spaced apart from the electrode roller 13 and extending transversely to the rotation axis of the machine.

From FIG. 2, the electrode roller 13 from the overhanging arm swing shaft 18
The spacing a is substantially larger than the spacing b of the end of the housing 11 towards the electrode roller from the above-mentioned pivot axis 18.
The housing 11, together with the hollow ball 12 contained therein, constitutes the majority of the weight of the overhang arm. This is because, as can be seen from FIG. 4, the pith is hollow, similar to the electrode roller 13. The hollow shaft 12 is rotatably supported within the housing 11 by a roller bearing 20.

Hollow Koji 1 from the outside of the housing between both roller bearings
2 and has a solid wall, so that the housing 11 represents the stationary part of the current transmission device, while the hollow shaft 12 represents the rotating part of this current transmission device. . In the axially sealed annular gap 21 between the housing 11 and the hollow shaft 12 there is a conductive material, for example mercury, for transmitting the welding current from the stationary part to the rotating part of the current transmission device. There is a fluid. As can be seen in FIG. 1, housing 11 is electrically conductively connected to a current path 22 which extends from one side of housing 11 laterally across the entire housing as seen in FIG. are doing. As can be seen from Figure 1,
The extending arm 1 can be moved up and down in a plane perpendicular to the side plate 15 by being supported in a swinging manner around a swinging axis 18.

The hollow electrode roller 13 itself has only a small mass, so that between the two electrode rollers 13 and 17 the side plate 1
5, no grooves or notches are created in the twill portion of the side plate. The necessary welding pressure is provided by a spring 23 supported on the machine base 19 and acting on the end of the shaft 12. As can be seen from Figures 2 and 3, the hollow shaft 1
2 is a cold soot supply path 25 for cooling the electrode roller 13;
and a return 26.

A supply channel 25 and a return channel 26 disposed inside the hollow shaft 12 in the form of an annular space are located concentrically with each other by a tube arranged in the center of the hollow shaft, with an annular hollow space between them. There is a space 27. The joint arrangement of the cooling chamber with a hollow space 27 intervening only containing space and the same arrangement of the return path extends to the electrode roller 13 at the front of the hollow shaft to further reduce the weight. However, the rear part of the hollow shaft 12 has no hollow space between the supply and return channels for the cold butterfly. The hollow shaft 12 is connected via an angularly movable coupling 30, for example a disc clutch, to an intermediate tube 31 through which the cold soot feed and return sections are separated and parallel to each other. Tubes 32 and 33 located at are adapted to penetrate therethrough.

In the area of the coupling 30 there is a flexible pipe connection for the supply and return of coolant. intermediate tube 31
is further connected to an electric motor 39, preferably a stepper motor, via another angularly movable coupling 36.
is connected to a hollow drive shaft 37 of a transmission 38 which is flanged. The feed and return channels of the sleeve extend through the transmission 38 and the hollow drive shaft 37. The soot is introduced and discharged via a rotary flow device of conventional construction, which is not shown in the drawings. The arrangement and configuration of the drive of the hollow shaft 12, as can be seen in FIG. It is also possible to consider providing it in the section. As can be seen from FIG. 4, the electrode roller 13 consists of a flange 41 integral with the hollow shaft 12 and a disc body 43 connected to this flange by screws 42. Annular electrode 44
is held vertically between the disc body and the flange 41.

This electrode roller has a hollow space 45 inside, and this hollow space is connected to a refrigerant supply 9*25 and a return path 26, so that cold soot can circulate inside the electrode roller. It is arranged to directly contact the annular electrode 44 which generates the largest amount of heat.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a schematic front view of an overhanging arm and a bearing in a machine stand according to an embodiment of the present invention. FIG. 2 is a scaled plan view of a driving device for an overhanging arm and an electrode roller. FIG. 3 is a sectional view of the overhanging arm taken along line A--A in FIG.
FIG. 4 is a sectional view of the front end of the extending arm supporting the electrode roller.・10...Extended arm, 11...Housing, 12...Hollow shaft, 13, 17...
・Electrode lo-fu, 15...Side plate, 16...
...Welding arm, 18... Swing axis, 19...
・Machine base, 21... Annular gap, 23...
Spring, 25... Supply path, 26... Return path, 27... Hollow space, 38... Transmission device, 39... Electric motor, 41...
・Flange, 43...Disc body, 44...
- Annular electrode, 45...Hollow space. Figure 1 Figure 2 Figure 3 Figure 4

Claims (1)

[Claims] 1 having two electrode rollers arranged one above the other,
The welding current is directed to each of these electrode rollers by means of a device for transmitting the current from a stationary part to a rotating part, one of these rollers being oscillated. In a resistance seam welding machine, the electrode roller 13 is supported on a movable overhang arm and further has a transfer device for advancing the workpiece to be welded relative to the electrode roller. is arranged on an overhanging arm 10 extending transversely to the direction of advancement B, which overhanging arm is spaced from the electrode roller and has a pivot shaft 18 extending transversely to its axis of rotation. a housing 11 which is rotatably supported within the housing and a housing 11 which is swingably supported within the machine table 19 and whose overhanging arm is swingably supported within the machine base 19 and which is rotatably supported within the housing; characterized in that it comprises a shaft 12 supporting at its end the electrode roller 13, and further characterized in that the housing constitutes the fixed part of the current transmission device and the part on which said shaft rotates. resistance seam welding machine.