JPH06210344A - Method and device for producing tubular body - Google Patents

Abstract

PURPOSE: To make it possible to extremely rapidly and cost effectively deform a flat strip material to a short tubular body by forming the strip material to a required length, then forming the material to a U shape, curving the material until its both longitudinal edges come into contact with each other and closing the longitudinal joint part by welding, etc. CONSTITUTION: A punching device 4 is disposed as a first working station. Many perforating punches and cutters are arranged in the device 4 to form a perforated flat sheet. In succession, a hand-over station 5 is disposed. Many stoppers and hand-over grippers are arranged in the station 5. Another working station 6 for deforming the sheet to a U-shaped component member is disposed behind the station 5. The U-shaped component member is supplied in a tubular form to another working station 7 and is supplied to a laser welding station 8 where the longitudinal joint part formed at the time of deforming is welded.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a method for making tubular bodies from flat strip material and an apparatus for carrying out the method.

[0002]

2. Description of the Prior Art It is known to wind flat strip material around a mandrel and provide a butt joint or an overlap joint which is closed in this case.

However, this known method is extremely time-consuming and requires a number of different and tedious operations on the strip material.

In addition, it is also possible to produce tubes of long length by continuous deformation, to weld the formed longitudinal joints likewise continuously and then to cut appropriately short pieces.

This method requires a mechanical device which is very inflexible and extremely long with respect to the diameter of the pipe to be manufactured.

It is also known to perforate still flat starting material, then bend it into a tube, weld it, and only then cut it to length. This requires complex mechanical equipment that is extremely inflexible. Furthermore, the tube becomes difficult to weld in the area of the holes and becomes non-circular.

[0007]

SUMMARY OF THE INVENTION It is an object of the invention to provide a method and a device which makes it possible to produce relatively short tubular bodies economically.

[0008]

According to the invention, the object is to form a strip of material to the required length in a first working step and then to form a U-shaped strip of material in a second working step. And then in a third processing step the strip material is curved until both longitudinal edges touch each other and then in another processing step the longitudinal joint is closed, for example by welding.

[0009]

The processing steps, in which the strip material passes continuously, allow the flat strip material to be transformed into short tubular bodies very quickly and thus economically.

As a result, even if the pipe diameter or the pipe length is changed, the minimum equipment cost is required. This is because each individual component can easily be adjusted to different dimensions.

In this case, it is very advantageous, according to the invention, to provide the strip material made of sheet metal with a large number of holes in the first processing step and to cut this strip material to a predetermined length.

This is very advantageous especially when producing inserts for silencers of motor vehicles with internal combustion engines. This is because it is possible to produce the correct size of strip material in a single operation and to provide this strip material with the required number of holes distributed over the entire surface.

In this case, the first processing stage can be directly associated with other devices or can be set up separately from these devices.

Furthermore, it is extremely advantageous to weld the longitudinal joints by laser.

Laser welding makes it possible to weld longitudinal joints in a particularly desired manner without undue heating and the material distortions associated therewith.

In a further advantageous embodiment of the invention, a measuring device is provided which controls the laser when welding the longitudinal joint and detects the edge of the longitudinal joint which has not yet been welded.

This controls the inaccuracies that may occur when the strip material is deformed into a tubular shape and prevents the laser from covering a large unneeded area.

In the apparatus of the present invention for manufacturing a tubular body from a flat strip material made of a thin metal plate, a large number of holes are provided in the supplied endless strip material, and the strip material is cut into a predetermined length. A first processing station with a punching device is provided.

The strip material can be prepared very economically only by this first processing station. In this case, it does not matter at all whether this first processing station is integrated into another device or is arranged independently of these devices.

Furthermore, according to another aspect of the invention, it is very advantageous to provide a large number of punching punches in the punching device, on the punching punch opposite the strip material to be punched. The sides are covered by plates that are arranged in an easily replaceable manner.

In this case, the required number of punches can be used in each case and can be fixed by plates.

Further, in the present invention, the lower surface of the plate may be provided with a notch into which an unnecessary punch is drawn for punching.

This allows the punching device to be equipped with a large number of punching punches which cover all possible punching patterns and to activate each required punching punch by simple replacement of the cover plate. This is because the unnecessary punches are pulled into the notches.

In order to facilitate the replacement of the cover plate, according to the invention, a punching device is mounted in the device in such a way that it can be moved transversely to the direction in which the strip material is conveyed.

In an advantageous embodiment of the invention, a delivery station is provided with a large number of extrudable stoppers, which can be extruded depending on the length of the sheet and with respect to the stopper the leading edge of the sheet. Are brought into contact with one another so that the seat is centered with respect to its respective length.

The delivery station cuts the perforated strip material to a predetermined length, regardless of whether the preceding cutting and perforating operation steps are integrated into the apparatus or performed independently of the apparatus. Adjust for the next processing step according to its size.

Particularly preferably, a vertically downwardly adjusted punch and a lower die of substantially U-shaped or semicircular shape are provided in a separate machining station, the punch being the punch. And at the end positions where the lower molds collide with each other, at least approximately to the bottom of the lower molds, project into the lower molds, and in this case the length of the strip material (sheet) between which the punch and the lower molds are deformed. Have at least approximately equal lengths.

Such a configuration of the processing station allows a very economical first variant of strip material.

In this case, it is particularly advantageous in accordance with the invention that the lower mold is provided with rotatably mounted rollers on the upper longitudinal edges on which the strip material drawn into the lower mold rolls. Move.

This allows the strip material to be deformed, in particular with material protection.

It is also very particularly advantageous according to the invention that a pusher bar is arranged at the bottom of the lower die, which pusher is vertically upwardly extrudable at least slightly from the lower die and between the pushbar and the punch. The strip material to be deformed is clamped.

This ensures that the strip material is retained at the beginning of the deformation and during the deformation process and is not displaced laterally.

Particularly preferably, the lower mold is formed from two parts, in which case both parts can be adjusted towards and away from each other.

When the two components are moved closer to each other, the upward legs are compressed further, so that the legs extend upward at least in the vertical direction after unclamping.

According to the present invention, a semi-circular upper mold as well as a semi-circular upper mold is provided in another processing station,
Between the two molds, the U-shaped deformed strip material is adapted to be clamped and deformed into a closed tubular shape.

More preferably, according to the invention, a laser welding device is provided, on the underside of which a conveying device is arranged for continuously conveying the strip material to be bent into a tube.

In this way, the longitudinal joints formed when the strip material is curved are closed in a very economical manner for continuous transport.

In the present invention, a roller driven as a conveying device is arranged.

Furthermore, a circulating tightening device may be provided as a carrying device.

In addition to carrying in a suitable configuration, the fastening device also carries out compression of the longitudinal joints. This results in improved welding results.

In a further advantageous embodiment of the invention, a longitudinally movably mounted laser welding device is provided, on the underside of which the clamping device for strip material is bent into a tubular shape. Are arranged.

This ensures that the tubular strip material is fixed exactly during the welding process.

In a further development of the invention, a sensor device is provided which detects the course of the longitudinal joints of the strip material to be bent and, in connection therewith, controls the laser welding device laterally.

This makes it possible to use a laser beam with a very small width and thereby to prevent adjacent areas of strip material from being exposed to unnecessary heat loads.

[0045]

1 shows an apparatus for producing a tubular body with the reference numeral 1. This relatively short tubular body, also called a short tube, is made from a strip 2 which is unwound from a storage reel (not shown) and fed flat into the straightening device 3.

A punching device 4 is provided as a first processing station in which a large number of punch punches and cutters are arranged to form a flat sheet having punched holes. . This punching device 4
A delivery station 5 is provided next to, and a large number of stoppers and delivery grippers are arranged in the delivery station.

Furthermore, the punching device 4 can be spatially provided separately from the delivery station, in which case the delivery station 5 is used as a loading station for the next device.

Behind the transfer station, another processing station 6 for transforming the sheet into a U-shaped component is provided. This U-shaped component is fed in tubular form to another processing station 7. This tubular component is supplied to a laser welding station 8 for welding the vertical joint formed during deformation.

FIG. 2 shows a sectional view of the punching device 4. In this case, a large number of punches 22 are provided in the plate 21 with holes.
Are movably supported in the longitudinal direction. Perforated plate 21
A cover plate 23 is arranged on the upper side of the cover plate, and a bag hole 24 is provided from the lower surface in the cover plate. Such a blind hole is arranged at a location where the punch 22 which does not have to function is provided.

When the punching device 4 moves closer, the punch assigned to the bag hole projects into this bag hole, while another punch is held in the pushed position via the cover plate 23 and is on the lower side. Make a hole in the strip material located at. At the same time, the perforated cutting pieces are cut as sheet 25 from the strip material via a cutter, not shown.

To change the hole pattern, only cover plate 23 is replaced with another cover plate with the appropriate pattern. To facilitate this, the perforated plate is mounted so that it can be pulled forward from the device.

On the unloading side of the sheet 25, as shown in FIG. 3, a large number of constantly driven rollers 31 are provided, and the sheet moves on these rollers 31. A further roller 32 is mounted on the upper side of the driven roller 31, which roller together is adjustable downwards towards the seat 25 and which can be pressed against the driven roller 31. The sheet is thus conveyed.

A large number of stoppers 33 that can be pushed upward in the moving direction of the sheet 25 are arranged. Each of these stoppers is pushed upward in relation to the sheet length and is used as a terminal stopper for the sheet.
This ensures that the seat is always centered regardless of its length.

In FIG. 4, the upper roller is omitted and the lower driven roller 31 is shown in a plan view. The sheet 25 is conveyed toward the pushed-out stopper 33 and is gripped by a gripper 41 which is movable laterally in the arrow direction 42 at a rear corner.

On the vertical side of the sheet opposite to the gripper,
A stopper strip 43 is arranged to support the sheet when gripped by the gripper. This stopper strip is adjustable laterally according to the width of the sheet. Gripper 421
When the user grips the sheet, the stopper 33 moves downward and away, and the gripper 41 conveys the sheet to the next processing station.

FIG. 5 shows a cross-sectional view of another processing station 6. The processing station has a punch 51 which projects downwards from above having a lower end with a substantially circular cross section. A U-shaped lower die 52 is arranged so as to face the punch 51.
Moves upward toward the punch 51 so as to plunge into the lower mold. In this case, the sheet placed on the lower mold is U
It is transformed into a glyph.

Rollers 53 for facilitating the introduction of the sheet into the lower mold are provided on the upper edge of the U-shaped lower mold and on both sides of the opening edge.
54 are arranged. The lower mold consists of two parts, the two parts being pivotally mounted separately and adjustable relative to one another.

Thus, after the sheet has been drawn into the lower mold, the lower molds are additionally compressed against one another and thus fix the U-shaped seat. This allows the seat to have legs that extend parallel to one another after being pulled out of the lower mold.

At the bottom of the lower mold is arranged an upwardly pushable push rod 55 which moves upward in the lower starting position of the lower mold and in this case moves the seat between the push rod and the punch 51. Tighten with. When the lower die moves upward, the push rod is returned at the same time.

The next processing station 7 shown in FIG. 6 is provided with a semi-circular lower mold 61 and a semi-circular upper mold 62, and a U-shaped curved sheet between these molds. Is tightened. In the center of the upper die, a knife-shaped cutter 63 is arranged so that it can be pushed downward.

When the two molds 61, 62 move closer to each other, both ends of the sheet move inward and make cutter contact, while at the same time the lower section of the sheet makes contact with the lower mold and of the lower mold. Take a shape. The knife-shaped cutter is then returned to support the ends of the sheet against each other.

When the two molds are moved closer together, the sheet also takes the shape of the upper mold in the upper section and is thus formed with a circular cross section, in which case the two ends of the sheet are in direct contact with each other. In this case, if necessary, the knife-shaped cutter can be extruded again in order to release the tubular component from the upper mold.

The tubular components are fed to the next station 8 where the laser welding equipment is located. Below the welding nozzle 81 there is arranged a rotatably mounted, driven roller 82, as shown in FIG. 7, which guides and conveys the tubular component. Used for.

An additional guide roller 83 is arranged on the upper side of the conveying roller 82, and this guide roller prevents the displacement of the constituent member during the conveying through the welding device.

A short distance before the welding nozzle is a sensor device 84 which detects the exact course of the longitudinal joints of the components which are bent into one another in the form of a tube and is thereby detected. Control the laser welding equipment laterally. A line camera is provided as the sensor device, but another sensor device may be provided.

Instead of the guide rollers and the conveying rollers, it is also possible to provide a clamping device, which circulates along a chain, for example, as shown in FIG. 8 for conveying the tubular components.

Another possibility of precisely forming the weld joint is obtained by immovably clamping the tubular component in a suitable receiving member and movably supporting the welding nozzle in the longitudinal direction.

[Brief description of drawings]

1 is a schematic view of an apparatus for producing a tubular body, in which a number of stations for processing and deforming flat strip material are located in succession.

FIG. 2 shows the interior of a first processing station for cutting and punching strip material to length.

FIG. 3 shows a transfer station for adjusting different lengths of strip material for subsequent stations.

4 is a plan view of a transport roller of the delivery station of FIG.

FIG. 5 shows another processing station having a punch and a U-shaped lower die for the first deformation of strip material.

FIG. 6 is a schematic view of a processing station having a semi-circular lower mold as well as a semi-circular upper mold.

FIG. 7 is a side view of another processing station provided with a laser welding device.

FIG. 8 is a plan view of a conveying device for tubular bodies to be welded.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 device 2 strip material 3 straightening device 4 punching body 5 delivery station 6, 7 processing station 8 laser welding device 21 plate with holes 22, 51 punch 23 cover plate 24 bag hole 25 sheet 31, 32, 53, 54 roller 33 stopper 41 Gripper 43 Stopper Strips 52, 61 Lower Die 55 Push Rod 62 Upper Die 63 Cutter 81 Welding Nozzle 82 Conveying Roller 83 Guide Roller 84 Sensor Device

Claims (19)

[Claims] 1. A strip material is formed into a desired length in a first processing step, then a strip material is formed into a U-shape in a second processing step, and then a strip material is formed in both longitudinal directions in a third processing step. Method for producing a tubular body from a flat strip material, characterized in that the edges are curved until they touch each other and then in a separate processing step the longitudinal joints are closed, such as by welding. 2. A strip material comprising a thin metal plate
2. The method according to claim 1, wherein the strip material is cut into a predetermined length by providing a large number of holes in the processing step. 3. Laser welding of vertical joints,
The method according to claim 1 or 2. 4. The method according to claim 3, wherein a measuring device is used to detect the edge of the unwelded longitudinal joint, which controls the laser when welding the longitudinal joint. 5. An apparatus for producing a tubular body from a flat strip material made of sheet metal, the endless strip material being supplied with a large number of holes,
5. A method according to any one of claims 1 to 4, characterized in that a first processing station with a punching device is provided for cutting the strip material to length. Device for doing. 6. A multiplicity of punching punches is provided in the punching device, the upper side of the punching punch opposite the strip material to be punched being covered by an easily replaceable plate. The device of claim 5, wherein 7. The apparatus according to claim 6, wherein the lower surface of the plate is provided with a notch into which an unnecessary punch is drawn for punching. 8. A punching device is movably mounted in the device transversely to the strip material transport direction.
Device according to any one of claims 5 to 7. 9. A delivery station having a large number of push-out stoppers is provided, which can be pushed out according to the length of the sheet, and the front edge of the sheet abuts against the stoppers. 9. The device according to claim 5, wherein the seat is adapted to be centered with respect to the respective length. 10. A vertically downwardly adjusted punch and a lower die formed in a substantially U-shaped or semicircular shape are provided in a separate machining station, the punch comprising a punch and a lower die. At the end positions where they collide with each other, at least approximately at the bottom of the lower mold, they have thrust into the lower mold,
10. The device according to claim 5, wherein the punch and the lower mold have a length which is at least approximately equal to the length of the strip material (sheet) which is deformed between them. 11. A roller rotatably supported on both upper longitudinal edges of the lower mold, on which the strip material drawn into the lower mold rolls. The device according to claim 10. 12. A strip material, in which a push rod is arranged at the bottom of a U-shaped lower mold, the push rod being vertically upwardly withdrawable at least slightly from the lower mold and to be deformed between the push rod and the punch. Device according to claim 10 or 11, wherein is tightened. 13. A device according to claim 10, wherein the U-shaped lower mold is made up of two parts, wherein the two parts are adjustable towards and away from each other. 14. A semi-circular lower mold and a semi-circular upper mold are provided in a separate processing station, between which the U-shaped deformed strip material is clamped and closed. It is designed to be transformed into a tubular shape,
Device according to any one of claims 10 to 13. 15. A laser welding device is provided,
15. The device according to claim 10, further comprising a conveying device arranged below the laser welding device for continuously conveying the strip material to be bent into a tubular shape. 16. The device according to claim 15, wherein rollers driven as a transport device are arranged. 17. The device according to claim 15, wherein a circulating tightening device is provided as the transport device. 18. A laser welding device, which is mounted so as to be movable in the longitudinal direction, is provided, and a clamping device for strip material that is bent into a tubular shape is arranged below the laser welding device. 15. The device according to any one of 10 to 14. 19. A sensor device according to claim 5, wherein a sensor device is provided for detecting the course of the longitudinal joints of the strip material to be bent and in connection therewith laterally controlling the laser welding device. The device according to item 1.