DE2914383A1 - Thermoplastics component frictional welding appts. - has rotary and axially movable spindle for one component and suction grippers holding other component - Google Patents

Abstract

Appts. for frictional welding of thermoplastics components has a spindle supported by a holder and carrying a component to be welded to a larger component. Spindle holder is supported by a support disposed externally of the frictional surface and the component is engaged by a counter support. Welding is no longer dependent on the size of components.

Description

Designation: Friction welding device and process

for friction welding Description: The invention relates to a device for friction welding and a method for friction welding.

The device for friction welding plastic parts has a friction workpiece holder, on a drivable spindle equipped with a feed device is arranged and one having a larger area formed by plastic Workpiece to be fastened takes up the friction workpiece and the softening heat on the friction surface generating moves and advances, and one connected to the advancing device Support device for the axial feed forces.

The method is used to produce a friction weld between a smaller, less deformable plastic part and a large plastic part with a curved or non-flat, elastically deformable container, housing-> Wall or blackboard surface.

Friction welding of plastics has been known for a long time.

Different possibilities, parameters and problems are in the following Brochures dealt with: R. Schaefer - Friction welding of plastics - in welding and Cutting (1970), No. 2, pages 56 to 62; H. Frehsel - Friction welding of plastics - in wt - Z. ind. Complete. 61 (1971) No. 8, pages 493 to 498; S. Nöckel - Problems of plastic friction welding - in ZIS-Mitteilungen 10/74, pages 1264 to 1272; M. Neitzel et al - Friction welding of plastics in chemical pipes, Plastververarbeitung 29. Jg. 1978, pages 319 to 324.

So far, friction welding has been modified slightly, if necessary Lathes, drilling machines or for individual special purposes of connection-smaller Mass-produced special friction devices. According to the aforementioned Writings, the failure of suitable friction welding devices is regretted. Diverse Usable friction welding devices, especially for joining plastic parts with large friction surfaces are missing so far. Above all, they seem to be rational Connect relatively large parts of a few decimeters in diameter to be taken into account Parameters, friction welding conditions and device parts have not yet been fully recognized to have become.

In the last-mentioned document there is only a simple workshop friction welding machine with simply infinitely variable, but not particularly brakable spindle drive and simple hydraulic feed system and simple common jaw chuck.

It does not allow the pipe section to be attached to a possibly even arched one Welding container.

Si drills and lathes will provide the required counterforce always brought on the back of the friction surface. Accordingly, the size is the Always parts through the projection of the spindle carrier or the center height of the lathe limited'. Also, up to now friction welded connections have only been made on planes or through corresponding pre-processing methods adapted areas or very small areas, where bumps are not important. However, if you want large-scale Establish friction welded joints, so one must both from the process design as well as the machine design are looking for suitable ways to initiate and absorption of the required forces without impairing the friction conditions allow to # free of shrinkage and shrinkage cracks friction welds all over the To be able to produce surface. So that the friction welding process is efficient and for different workpieces of large dimensions is suitable, must device and processes take into account the different circumstances, as special machines not extra for the much smaller series or constantly changing conditions can be made.

Accordingly, the invention addresses the problem of the friction welding device to connect quickly with the larger workpiece and convert the friction surfaces into one for Bring the reaming of the friction workpiece suitable position.

To achieve this, the part relating to the device sees the Invention a arranged outside the friction surface connected to the spindle holder Support and one effective from the outside in the opposite direction to the pressure direction of the spindle counterforce holding device acting on the larger workpiece.

Such a device can be of any size at any point Workpiece to be applied. With the support, it lies down in the area of the friction surface on the workpiece. The counterforce holding device pulls / essentially the workpiece against the support and all forces are only from the outside of the workpiece applied and supported. Friction welding is no longer the size of the Workpieces dependent and the device can be attached quickly. According to a In an advantageous further development, the counterforce holding device is located outside the support. In principle, the arrangement can also be reversed for special cases especially when parts are machined on a standard support that are just about their size, but that small parts should be rubbed open, that one can retract-accommodate means within the support.

However, it is particularly useful if the counterforce holding device is outside. Then the support limits a completely free and clearly defined one Area for rubbing in a predetermined plane while the counterforce holding device parts can be anywhere outside.

The counter force holding device parts can with purely mechanical Means work. However, it is expedient to form them with piston-cylinder units, one ends of which are connected to the spindle support, while the other ends Ends equipped with attack elements for attachment to the large workpiece are. At least two of such piston-cylinder units should be provided, however, it can also be three, four or six. You should be evenly around the Support to be distributed to attract the workpiece well.

Hooks, claws, grippers for eyelets, undercut ones are used as attack elements Parts or the like in question that are either present on the workpiece, or by any method, in particular by gluing or rubbing on can be attached. Since plastic surfaces are usually smooth, they are suitable as attack elements for fast work suction holder. These should be interchangeable especially if the device is not only used for a specific product will. If they are articulated to the piston-cylinder assemblies, they can can also be placed on surfaces that are inclined to the friction plane or that are used to to bring the workpiece into one plane. To let the holder attack in a variety of ways, the piston-cylinder units are expediently articulated on the spindle holder at one end and at the other end secured against sideways evasion. A special one easy work and good accessibility to the friction area as well as safe Bracket arise when the support of a partial open Aufsetzkrone is formed on the articulated on opposite sides Holding arms are provided for the piston-cylinder units. Such a device construction is easy and inexpensive to manufacture. It can also be designed to be interchangeable.

The whole device is with stable holding and guiding; average to be equipped for versatile adjustment and locking of the friction spindle unit, for example in the manner of a column drilling machine with a height adjustable on a column Slide, a swiveling connection between the slide and the spindle holder and above all a mechanical feed and retraction device for the whole Spindle holder as well as expediently also with a sliding guide for the column, especially when used for welding nozzles on large container walls or the like, which are set up in front of the friction welding device.

One. Such a device can also be attached to a non-flat surface from the outside Apply elastically deformable container wall or the like made of plastic and they are elastic with the help of the counterforce holding device and the support in the friction area deform into a plane. With it one can for the first time directly, not evenly bar on a container wall without special pre-processing a smaller plastic workpiece, for example fasten a pipe connection, a socket connection or the like.

It was recognized that within the scope of the problem according to the invention, namely to bring the friction surface into a suitable position for the application of larger parts, a generally new procedure has been found which makes it particularly simple Way allows to make connections with large uneven parts that however, it is not tied to the fact that the supporting forces are applied from the outside.

In such a procedure according to the invention, the arched or uneven surface in one of the size of the smaller plastic part to be attached corresponding area resiliently to a plane at least in one ring area The surface is deformed and the smaller plastic part is rubbed and the forces for the elastic deformation of the large plastic part are canceled. Man has recognized that plastic sheets> such as container walls or the like, can be deformed to the required extent without adverse long-term effects and that the low residual stresses are well absorbed, especially since the plastics themselves adapt to this shape through their creep behavior. You can see this deformation even a long time before the actual rubbing process with the inventive Carry out device by, in special cases, the straightening forces overnight can act and / or possibly also the large workpiece in the straightened Position heated for example by warm air.

According to the invention, the friction welding process can now be used as a fast one and inexpensive methods in place of the otherwise very time-consuming and costly Connection of pipe connections, retaining lugs or the like with larger plastic parts such as containers, pipes or the like occur. The forces for elastic deformation of the large plastic part is best lifted after the friction connection has cooled down on. Although it is also possible to hold the workpiece from behind against a support to press and keep level, however, it is particularly expedient within the scope of the invention to the deformation forces for the elastic support as support pressure forces and tensile forces to attack the large workpiece from the outside, so you are in the size of the workpieces used are not limited and can use the device according to the invention, However, which is also suitable for flat parts, use it in a particularly simple manner. Further essential features are also in the following with reference to the drawings given part of the description.

The invention is explained in more detail below with reference to the drawings and described.

1 shows the side view of a device for rotary friction welding with a container wall shown in section, which is in the friction welding position is deformed; FIG. 2 is a view of the friction welding device according to FIG. 1 from the left but without container wall; 3 is a horizontal section along lines 3-3 in Fig. 1 and 2 through the friction welding device and the container wall in a somewhat larger format Scale and partly more precise representation with schematic indication of some circuit elements and FIG. 4 shows a diagram of the various process and welding parameters.

The friction welding device 10 shown in FIGS. 1 to 3 is used in this example to "a" wall 11 of a container of large diameter to attach a nozzle 12 in the friction welding process. The container with the wall 11 stands on the floor 14 in front of the friction welding device, which is on floor rails 15 has horizontal guide rails 16.

On the horizontal guide rails 16 is, with the help of the drive motor 17 movable, the base frame 18 of a column 19 guided. To his The horizontal and vertical rollers 20 serve as guidance. The drive motor 17 can the column 19 at a desired distance from the one here forming the container wall 11 larger workpiece can be brought. The spindle holder 21 has a vertical slide 22, which is guided in a height-adjustable manner on the column 19. To its height adjustment a screw spindle 23 is used, which is inserted into a corresponding nut 24/22 on the vertical slide intervenes. The screw spindle 23 is rotated with the aid of the gear motor 25 and thereby the vertical slide 22 up and down into the desired position emotional.

A horizontal guide housing is pivotable about the axis 26 on the vertical slide 27 attached. It is with the help of the rotary guide rings 28 on the vertical slide 22 attached. The locking means are not shown in detail. It becomes appropriate an angle scale is attached for setting the required inclination of the spindle.

In the horizontal guide housing 27 is in the direction of the main axis of rotation A feed and brake cylinder 30 is guided in a displaceable and lockable manner. He wears on his that Vertical slide 22 opposite side one Rack 31, in which a pinion 32 engages, which on a with the handwheel 33 connected shaft 34 is rotatably arranged. The shaft 34 is in the horizontal guide housing 27 rotatably mounted. The sliding connection can be tightened with a toggle 35 will.

At the rear end of the feed and brake cylinder 30 is a motor 37 flanged. It is an electronically adjustable speed and a motor that can be suddenly braked electronically.

Inside the feed and brake cylinder 30 are three cylinder-fixed Cylinder space boundary walls 38 with the help of ring seals and shaft locks attached. They are penetrated by a hollow feed piston rod 39. These carries two piston disks 40 fastened with shaft locks, which are sealed, however, are slidably guided in the cylinder 30. The hollow feed piston rod 39 has a sufficient length in both end positions between the cylinder boundary walls 38.1 and 38.3 to be sealed. Triple seals in these cylinder walls ensure a perfect seal.

A radial bearing is located in the front end 39.1 of the feed piston rod 41.1 and a thrust bearing 42.1 attached.

Approximately in the middle is another radial bearing 41.2 and one in the reverse direction effective axial bearing 42.2 arranged. The spindle is in these 43 rotatable, but not axially displaceable with respect to the feed piston rod 39 stored. The rear end 43.1 of the spindle 43 is splined 44 provided, which is axially displaceable in a splined sleeve 45, but non-rotatable intervenes. The splined sleeve 45 is rotationally fixed on the motor shaft 46 of the motor 37 and fixed axially immovable. The spindle 43 is rotatable and axially displaceable to drive. It can be moved with the aid of the piston disk 4a2. The spindle 43 carries at its front end a chuck 47 in which a friction workpiece holder can be replaced 48 can be used. The friction workpiece holder 48 can be exchanged for a drill chuck will. The friction workpiece holder 48 carries a pressure disk 48.1 with it, for example a centering attachment 48.2, onto which the pipe socket 12 is slipped as a friction workpiece 12 is. An adhesive strip 49 secures the non-rotatable connection.

On the front end 30.1 of the feed and brake cylinder 30 is a support 50 is placed on it. It is made of a pipe which runs along the line 50.1, as can be seen from FIG. 3, is excluded to one side Access to the chuck 47, the friction workpiece holder 48 and the friction workpiece 12 to obtain. The front end 50.2 is provided with recesses 50.3 so that support webs 50.4 stop and a support crown results, within which the friction surface RF lies.

On the attachment attachment 50.5 are on opposite sides the bearing blocks 51 attached, on which pneumatic 52 piston-cylinder units with Help the bolts 53 are pivotally mounted. The front ends 54.1 of the piston rods 54 are screwed into connecting and pivot bearing rods 55.

When the horizontal guide housing is not swiveled, the connection and pivot rods 55 vertically, as can be seen from FIG. 1. There are suction cups on them 56 pivoted. They have dovetail guides 56.1 into which the Suction cups 57 can be plugged in interchangeably. The suckers 57 are with the screws 56.2 secured. The suction cups 57 are designed according to the workpiece. In the exemplary embodiment they are, as illustrated in FIG. 2, designed as elongated rectangles. One elongated ring seal 58, each semicircular in the upper and lower areas is performed, ensures an airtight system on the surface 11.1 of the larger Workpiece. Against lateral evasion of the suction cups 57 as a result of undesired pivoting of the piston-cylinder units 52, the connecting and pivoting rods 55 are on their outer ends articulated with retaining arms 59, which in turn on bearing journals 60 sit on opposite sides of the support 50 attached 4ih in the area of the webs 50.4, as can be seen in more detail in FIG. So the piston rods 54 can be extended and retracted freely, with they pivot slightly. The suction cups 57 can with their suction holders 56 pivoted on the connecting and pivoting rods 55 to adapt to the surface shape are set in each case according to the deformation forces. To compensate sideways movements when pulling straight, the suction holder 56 should be slightly sideways be slidably mounted.

The suckers 57 are via a suction air line 65 and a shut-off valve 66 connected to a suction air source 67. In the drawing is the clarity only the line 65 to the right sucker 57 is shown in FIG. 3. she leads also to the left suction cup 57 * For the control of the pneumatically operated Rib cylinder assemblies 52, a valve 68 is provided, to which the two lines 69.1 and 69.2 of the cylinder 52.

The left cylinder 52 is also connected accordingly.

A compressed air line 70 connects the valve 68 with the maintenance unit 71, which is a pneumatic unit with filter, pressure control valve and oiler which is connected to a pressure belt source 72. The compressed air line 70 leads also to a valve 73> to which the lines 74.1 and 74.2 are connected which lead to the feed cylinder space 30.4 and 30.5. The lines 74.1 and 74.2 are also partially shown in the wall of the cylinder 30. The lines are also shown schematically The space 30.6 of the cylinder 30 and the space 30.7 are with a practically incompressible pressure medium, such as Hydraulic oil filled, its leakage from a pressurized storage tank 76 are fed via a check valve 77. To the one adjacent to the pneumatic space 30.5 Hydraulic space 30.7 leads the hydraulic line 78.1. To the opposite hydraulic room 30.6 leads the hydraulic line 7.2. These can be included within the cylinder wall their valves lie. The valves and throttles are only for the sake of clarity schematically relocated to the outside. The lines 78.1 and 78.2 are through a check valve 79 connected to one another in such a way that the pressure medium from space 30.7 is unthrottled can flow into space 30.6, but not the other way around. Parallel to the check valve 79 an adjustable throttle 80 is connected, for example as from the end face can be formed in the cylinder screwable needle valve.

Parallel to both valves is a stopcock 81, which is also a gradually closable throttle valve. The throttle 80 is so dimensioned or adjust so that it only lets through a very small and slow flow of oil> while the throttle and / or shut-off valve 81 completely covers the line cross-section can release and enables a rapid flow of the oil if it is whole is open. Manual actuations 66.1> 68.1, 73.1 and 81.1 are required for all valves shown. With them, the machine can mainly be used for smaller series and for test purposes can be controlled very easily and well by hand.

Instead of or in addition to manual controls, remote controls can also be used be provided on the valves, so that the device can be wholly or partially can be operated by means of a program control.

The electrical line for supplying and / or controlling the motor 37 is denoted by 83. It leads to an electrical switching element 84> which is only shown schematically as a box. This is used to switch on and off as well as for speed setting and for sudden braking of the motor 37. It can, as indicated schematically by the dashed line 85, with the actuation 81.1 of the valve 81 of the hydraulic braking device, as explained below, coupled are to this valve 81 when braking the motor 37 immediately according to the Open friction welding conditions.

With the device and the procedure according to the invention worked as follows.

The workpiece with a larger area formed by plastic, here, for example, a curved container wall 11 is in a position near the Horizontal guide rails brought. The device shown can be flat Parts or also cylindrically curved parts, such as container walls, or otherwise irregular and unevenly shaped parts are used. With the illustrated Suckers 57 with closed seals 58 can hold parts that at least one of the size of the suction cups 57 and smooth ones corresponding to their spacing Have surface, here for example surfaces with radii of curvature of 400 mm and more. With the drive motor 17, the column 19 is at a desired distance from the workpiece 11 brought so that fine adjustment with the handwheel 53 is still possible. With the gear motor 25, the spindle holder 21 is brought to the desired height. If necessary, its axis A is brought into the desired angular position. Then the support 50 brought into contact with the wall 11 by turning the handwheel 33. By actuation of the valve 68, the piston rods 54 are extended and the suction cups 56 for contact brought to the surface 11.1. After actuation of the valve 66, the suction air acts in the spaces between the seals 58, so that the / 57 suction cups are on the surface 11.1 and hold it firmly. By actuating the valve 68 compressed air is directed into the cylinder space (not shown) adjacent to the container wall 11 and the piston rods 54 are drawn in and the suction cups 56 are moved back so far, until the curved surface in the friction surface area RF within the crown-shaped support 50 is brought into a plane, at least in the ring area that the plastic pipe socket 12 opposite. The plastic pipe socket 12 is on the friction workpiece holder 48 attached so that it is supported on the thrust washer 48.1.

An adhesive strip 49 applied to the circumference of both holds him tight. Now during the expanse; Compressed air into the Cylinders 52 securing the holding of the workpiece on the friction welding device 10 by actuation of the valve 73 compressed air is passed through the line 74.1 into the feed chamber 30.4, so that the piston disk 40.2 moves in the feed direction V and thereby the Feed piston rod 39 takes with it. This takes the spindle via the axial bearing 42 43 with. This moves in the splined sleeve 45. The disc piston 40.1 displaces the oil from the brake cylinder chamber 30.6 via the line 78.2. So that the feed takes place in rapid traverse, the valve 81 is opened so that the throttle 80 bypassed will. Just before the Reibwerkstückstirnfläche 12.1 on the surface 11.1 of the larger Workpiece 11 touches down, the valve 81 is closed and by actuating a corresponding switch in the switching element 84, the motor 37 is set in rotation, so that the friction workpiece 12 is rotated. The speed is set to a value the diameter and the size of the friction surface taking into account the material properties is equivalent to. Some of the processes described above can run simultaneously.

The various parameters of the process and the welding process are shown in FIG. The time is shown on the abscissa. On the ordinate different parameters are given in each case. The representation is not linear, but is only intended to show the relationships and possible progression of the individual values. In the top, 1st diagram, the pressure pzv in the feed cylinder space 30.4 is shown.

In the 2nd diagram below, the reverse thrust pressure pzr is in the reverse cylinder space 30.5 shown.

In the third diagram is the feed or return speed VG of the spindle 43 and thus of the friction workpiece 12 is shown.

In the fourth diagram with the designation V is the course of the vacuum V shown in the suckers 57.

The return path W of the suction devices 57 is shown in the fifth diagram.

The sixth diagram shows the penetration depth s of the friction workpiece 12 shown greatly exaggerated in the area of the wall 11 starting from the surface 11.1.

In the seventh diagram, the speed n of the motor 37 is shown.

The eighth diagram shows the temperature J in the weld seam.

The switch-on processes described above take place in, the period of time from the beginning of a cycle at time t0 to time t3 in the 5th diagram. They can also take place in a different relative time allocation than was previously done one after the other has been described. In any event, the device as a whole is at time t3 ready for the rubbing process. The spindle 43 is driven by the pressing force in the feed chamber 30.4 according to the relatively high speed when the valve is open 81 advanced at rapid traverse up to time t6.

The pressure oil is removed from the at a relatively high speed Brake chamber 30.6 diverted into oil chamber 30.7. Shortly before the point in time was reached t6, the motor 37 is switched on at time t4 and is open until time t5 accelerates its set maximum speed. When he has achieved this, will valve 81 is closed at time t6, so that the feed rate VG, as can be seen from the 3rd diagram VC, drops considerably, for example to Values from 0.05 mm / s to about 0.1 mm / s or 0> 3 mm / s.

This reduction in speed is due to very heavy throttling of the oil flow of the line 78.2 in the throttle 80 is reached. It is essential to good friction welding and working with low torques with large friction surfaces.

While in the feed cylinder space 30.4 the constant pressure pzv - like can be seen from diagram 1 - prevails, the friction workpiece 12 until the point in time t7, the touchdown on the surface 11.1 5 slowly advanced. Begins at time t7 the rubbing process. The speedn decreases slightly and the temperature ffi increases from room temperature at a constant low feed rate almost linearly or approximately parabolically up to a maximum value of max. Has in this state the friction zone RZ the largely liquid required for the friction weld connection State at time t8 achieved. Until time t9, i.e. in the softening phase T1 is at a constant low feed rate VG the friction workpiece 12 according to the 6th diagram with the representation of the penetration depth s has been pushed forward evenly and pressed into the wall 11. It has it covered a distance of about 1 to 2 mm. Upon reaching the highest desired Temperature v max and lowest viscosity is activated at time t8 of the switching member 84 of the motor 37 electronically braked abruptly, so that a further rubbing and thus a further supply of heat in the friction zone and that through the rubbing caused the associated molecules to tear off stops.

The braking takes place within a very short time, for example a period of time of less than 1 s. At the same time, the valve 81 is now either suddenly or gradually opened depending on the friction conditions. This can significantly reduce the hydraulic oil be expressed more quickly from the brake chamber 30.6 by bypassing the throttle 80. As can be seen from time> t9 to t 11, the speed VG rises steeply to the multiple value of about 0.5 mm / s to about 1 mm / s. At the same time penetrates the friction workpiece 12, as can be seen from the 6th diagram, much faster in the wall 11, which leads to a compression of the parts to be welded with a larger Pressure leads. Since the Temperaturyü, as can be seen from the 8th diagram, steeply through Cooling and displacement of the warm melt decreases, occurs from time tll to at time t12 the solidification in the friction zone RZ. Included the workpiece 12 follows the shrinkage completely, so that voids and shrinkage cracks be avoided. Its feed rate VG decreases according to the hardening initially steep and then gradually / to 0 until t12. It has its final location achieved.

In this phase it is only a fraction of a further 'millimeter penetrated. However, this change in feed rate is particularly effective for large ones Share a good connection and allow it to work with relatively little torque and large parts of up to 5 decimeters, for example, at sufficient speed To rub the diameter. With a 1 KW motor that you can only use for a short time Used friction welding process, you can without too much overheating because of the large Work intervals with torques 30% and more above the normal values and thereby obtains a much lighter and cheaper device. Possibly. can, as shown in dashed lines in the first diagram pzv, the holding pressure when cooling increased if this appears necessary. The heating and softening process has become in the vertical dashed line running through all the diagrams Lines of the area T1 played between the times t7 and t9. He is finished by the sudden braking of the drive motor 37 between times t8 and tlO. Braking and switching of the valve 81 can be carried out with one another in the manner known to the person skilled in the art common ways electrically, electronically, mechanically, hydraulically or pneumatically be coupled.

When still acting as shown in diagrams 4 and 5 The vacuum in the suction cups and the wall 11 held therewith is after they have completely cooled down the weld seam at point in time t13 removes the pressure pzv in the cylinder chamber 30.4, by switching over the valve 73 and the back pressure nzr into the cylinder space is established 30.5 passed so that the spindle 43 is moved back after the adhesive tape 49 is removed. The connector 12 remains on the wall 11. The brake oil flows from the room 30.7 especially via the check valve 79 back into the room 30.6. This back pressure is effective in the time periods t13 to t15. The withdrawal is between the time periods t 13 to t 14 shown in the third diagram VG. Now the friction workpiece holder can 48 taken from the chuck 47 and exchanged for a drill or boring tool will.

In another feed and turning cycle T2 between the times t16 and t18 can now be the space within the welded connection piece 12 - the in Fig. 3 is shown in dashed lines in the front friction workpiece holder position - be drilled or gouged out. As a hydraulically braked pneumatic Feed device and a speed adjustable motor are provided, can very be delicately twisted out or gouged out. Only after time t18 after the boring, during the retraction of the spindle 43, the vacuum in the suction cups 57 canceled and the suction cups 57 can be used again to be advanced as shown up to time t19. The container wall 11 now resumes in the part in which it has not been worn away, its rounded shape is provided, provided that it is has not been slightly deformed by creeping and friction #.

A new container wall or the like can be in a similar Another workpiece can be added quickly to the cycle. By working from only one side can be particularly quickly in different places or different Walls are worked.

With the device and the procedure described one can achieve particularly short welding times of up to about 10 seconds. The cooling times take up to 300 sec.

A high welding quality, which is also very reproducible, can be achieved, be achieved. Since you can deform the welding zone into a plane, you can now something can also be attached to uneven or curved parts by friction welding, if the surfaces allow a membrane-like deformation. This can be in special cases can also be started a long time before the friction welding process in order to achieve the Exploiting creeping behavior. Since the restoring forces are not too great, are The stresses during the machining process and the residual stresses are also low They are further broken down by crawling.

The device and procedure can not only be used in rotational friction welding but can also be used in oscillation friction welding. The initially smooth one Alignment of elastically deformable parts for welding on plastic can also can be used for other vibration welding processes. Switching the feed rate can not only be used with such devices and procedures, where -the forces are applied from one side to the larger workpiece, but also in those devices and procedures in which the support from the opposite side.

The speed can be switched to several different modes Way. It is important that the feed device with a large feed force can work, a switchable braking device is assigned.

In special cases, mechanical solutions could be sufficient, provided you work smoothly. However, with the small feed distances, this is only a fraction one millimeter difficult or hardly to reach. Hydraulic braking devices are better suited because they can be regulated much more sensitively. It is suitable The switchover with a hydraulic valve is particularly suitable for the sensitive solution that is easy to switch and can also be classified in a program. However, it is also possible if it is for device or procedural reasons makes sense to the one designed in different ways normal rapid traverse feed to mechanically couple a hydraulic braking device for the creep speed, whose Connection can easily be released and switched on again, for example by Pawls that are connected to the drag piston.

The supports or abutments and the suction cups are in their shape and size to match the ~ workpieces. Instead of the suction cups you can also use existing ones Undercuts, eyelets, cavities or the like are attacked. Also can When attaching larger parts, smaller holders are first used by friction welding or attach by gluing, in which the tensile forces for holding are then initiated will. After only small parts or pipes were previously connected by friction welding, it is easily possible with the device according to the invention at three meters high Containers at any point, pipe connections or for the mechanical Structure to attach important connection elements quickly and inexpensively.

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Claims (11)

Designation: Friction welding device and method for friction welding Claims: 1. Device for friction welding plastic parts with a friction workpiece holder, on a drivable spindle equipped with a feed device is arranged and one on one a larger area formed by plastic having workpiece to be fastened takes up friction workpiece and on the friction surface moves and advances generating the softening heat, and with one with the advancing device connected support device for the axial feed forces, d a d u r c h g e -k e n n n e i c h n e t that an outside of the friction surface (RF) arranged> with the spindle holder (30) connected support (50) and opposite to Pressure direction (V) of the spindle (43) effective from the outside on the larger workpiece (il) attacking counterforce holding device (52,56,57) are provided. 2. Apparatus according to claim 1, since dur c h g e -k e n n z e i c h n e t that the counterforce holding device (52, 56, 57) outside of the support (50) is arranged. 3. Apparatus according to claim 2, d a d u r c h g e -k e n n z e i c h n e t that the counterforce holding device at least two evenly around the Support (50) distributed, one end attached to the spindle holder (30; 50.5, 51) Has piston-cylinder units (52), the other ends (54.1) of which with engagement elements (56, 57) are equipped for attachment to the large workpiece (11). 4. Apparatus according to claim 3, d a d u r c h g e -k e n n z e i c h n e t that the engagement elements are suction holders (56, 57). 5. Apparatus according to claim 4, d a d u r c h g e -k e n n z e i c h n e t that the engagement elements have replaceable suction cups (57). 6. Device according to one or more of claims 1 to 5, d a it is indicated that the engagement elements (56, 57) are articulated (55,56) are attached to the piston-cylinder units (52/54). 7. Device according to one or more of claims 1 to 6, d a it is indicated that the piston-cylinder units (52) on one End (53) articulated to the spindle holder (30, 50) and at the other end (54) against lateral evasion secured (59) are performed. 8. Device according to one or more of claims 1 to 7, d a it is indicated that the support (50) from a partial open Aufsetzkrone (50.2, 50.3, 50.4) is formed on the opposite Articulated support arms (59) for the piston-cylinder units (52, 54) are provided on the sides are. 9. A method for producing a friction weld between a smaller, little deformable plastic part and a large plastic part with a curved or non-flat, elastically deformable container, housing, wall or board surface, which shows that the arched resp. uneven surface (11.1) in one of the size of the smaller plastic part to be fastened (12) corresponding area tF) elastic to at least one ring area (RZ) flat surface is deformed and the small plastic part (12) rubbed and the forces for the elastic deformation of the large plastic part (11) are canceled will. 10. The method according to claim 9, d a d u r c h g e k e n nz e i c h n e t that the forces for the elastic deformation of the large plastic part (11) after the friction connection (t 18) has cooled down. 11. The method according to claim 9 or 10, d a d u r c h, one g e k e n n z e i h n e t, the deformation forces for the elastic deformation as support pressure forces (50) and tensile forces (52, 57) attack the large workpiece (11) from the outside (11.1) leaves.