EP0772501B1 - Method of forming a neck and flange on a cylindrical hollow body and a device for carrying out the method - Google Patents

Abstract

A method and an apparatus for forming circumferentially extending necked and flanged parts at an end of a bilaterally open hollow cylindrical body. First and second axially aligned shafts carry axially displaceable first and second inner tools, respectively. Each inner tool has a circumferential body-shaping and a circumferential body-supporting surface. In a first axial position of the two inner tools the shaping surfaces together define a circumferential shaping groove situated inside the hollow body, and the body-supporting surfaces support the hollow body. In a second axial position the two inner tools are at a greater axial distance from one another than in the first position to allow introduction of a hollow body therebetween. A third shaft, carrying an outer tool having a circumferential shaping surface, extends parallel to the first and second shafts. A positioning arrangement is provided for aligning the circumferential shaping surface of the outer tool with the circumferential shaping groove and for radially moving the outer tool towards the two inner tools such that a circumferential portion of the hollow body is deformed and forced into the shaping groove causing the two inner tools to axially spread apart from one another.

Description

The invention relates to a method for forming a tipped and crimped Section at one end of a cylindrical hollow body open at both ends, in particular a can frame, by means of two internal tools and one External tool, the internal tools, of which at least one is rotationally driven, moved axially relative to the hollow body in its interior and then the outer tool radially against the the internal tools located hollow body is moved that the provided section of the hollow body in one of the two inner tools commonly formed concave circumferential contour is pressed and the outer tool and the inner tools in their starting position the back of the deformed body.

The invention further relates to a device for performing the above Procedure for the end to be teased and flared of the cylindrical Hollow body two axially movable inner tools, of which at least one is drivable, with one corresponding to the tipped and crimped end Contour and a radially movable against the inner tools has outer mold.

A generic method and a corresponding device are off known from EP 0 290 874 A2. The known device is suitable for Simultaneously teasing and flanging both ends of an open at both ends Can frame. It has a tool arrangement for each end each consisting of two inner tools and one outer mold. The Both inner tools of each tool arrangement are as drivable Shaft fixed disc and designed as a swash plate. The fixed disc has a cylindrical outer surface to which in the direction of the swashplate, a tapering contour connects the Neck contour of the finished shaped box corresponds. The diameter of the cylindrical surface is smaller than the inside diameter of the tipped end the can frame and thus significantly smaller than the inside diameter of the cylindrical wall of the can frame. The swashplate, which by its nature is radially adjustable and accordingly has no fixed axis of rotation, is formed from two washers, the flanging or flange contour of the tipped and flared end of the can frame. Both Ring discs are fixed radially against each other by an annular shoulder, but slightly displaceable in the axial direction, the Ring shoulder has a diameter that is slightly smaller than that Inside diameter of the undeformed can frame.

A disadvantage of the known device is that the can frame at its Recording only due to the diameter ratio of the inner tools is gripped by a narrow edge of an annular disc. This is one safe transport of the can frame in the circumferential direction is not ensured, and it can be due to the between the can frame and the internal tools possible slip to paint damage to the can frame.

Other known devices for teasing and crimping the open end the can body of a so-called two-part can (which in the finished state consists of two Share, the can body forming a piece with the bottom and a Cover) consists essentially of a the bottom of the hollow body axially fixing floor stamp, two internal tools through which the Wall of the cylindrical hollow body in the phase of teasing and flanging is supported on the inside, and an outer mold that the Teasing and flaring the can body causes. One such device is known from DE 28 05 321 C2 and US Pat. No. 4,070,888. Point at her the two inner tools have different diameters, at least the diameter of one of the two inner tools is much smaller is the inside diameter of the tinned can body. The two Internal tools are staggered on a common shaft Shaft sections slidably arranged against each other. After the The can body is pushed over the two inner tools using the base stamp has been, the wall of the can body by an eccentric Infeed of the inner tools against the outer mold pressed. While the outer mold cannot be moved axially, the two inner tools will work in opposite directions depending on the infeed depth axially shifted. Only the outer one is driven in rotation Molding tool; the internal tools must therefore be above the one in between Can body is brought to the required target speed. Also in this known device it comes as a result of between the can body and the internal tools slip to paint damage on the can body. Furthermore, the ring contour of the outer mold leads to wrinkles in the (tucked) area of the Can body.

In another known device of the latter type, the two inner tools also have different diameters, whereby in this case too, at least the diameter of one of the two inner tools is significantly smaller than the inside diameter of the teased, again the body of a hollow body representing a two-part can (EP 0 588 048 A1). The internal tools are arranged on a shaft, whereby one of the inner tools is axially displaceable. After the hollow body has been pushed over the two inner tools and after eccentric Infeed of one of the inner tools is done by radial infeed axially displaceable outer form roller against the wall of the hollow body the inner tools pressed. As a function of the infeed depth, the Form roller and one of the inner tools axially displaced. With this device only the axially displaceable inner tool is driven in rotation. This known device also damages the paint on the hollow body. There is also an uneven crimp.

Another device is known, the two axially displaceable and radial fixed inner tools as well as an axially fixed and radially movable outer Has molding tool (EP-PS 0 520 693). Here too, the two have Inner tools of different diameters, the inner tool can rotate with the smaller diameter in an eccentric position, in contact with the body, which in turn forms the body of a two-part can Hollow body. The outer mold is capable of radial movements perform while the cylindrical hollow body rotates. It will outer mold in the section of the to be teased and crimped Hollow body pressed. Even with this device is because of the different Diameter of the two inner tools no uniform flaring to achieve.

The invention is based on the object, the method and the device to improve the type mentioned in that the described Disadvantages do not occur and that with the new method or new device hollow cylindrical bodies open at both ends, in particular Frames of three-part cans, tucked and flanged to protect the surface can.

• Die beiden Innenwerkzeuge werden von einer voneinander entferten Position mit entgegengesetzter Richtung in den Hohlkörper eingefahren,
• in der Lage des geringsten Abstandes zwischen den beiden Innenwerkzeugen wird der Hohlkörper von diesen axial fixiert und axial kraftschlüssig erfaßt,
• es wird ein zusätzlicher, radial wirkender Kraftschluß zwischen mindestens einem Innenwerkzeug und dem Hohlkörper hergestellt
• und das Außenwerkzeug wird formgebend gegen den Hohlkörper angedrückt.

As far as the procedure is concerned, this task is solved by the following steps:

• The two inner tools are inserted into the hollow body in a direction opposite to one another,
• in the position of the smallest distance between the two inner tools, the hollow body is axially fixed by these and gripped axially,
• an additional, radially acting frictional connection between at least one inner tool and the hollow body is produced
• and the outer tool is pressed against the hollow body in a shaping manner.

By retracting the inner tools from opposite one another distant positions in the hollow body and by returning to the Starting positions can be with the parts moving into the hollow body a relatively large diameter. And this can Diameter larger than the diameter of the tipped part of the hollow body, because the inside tools are on both sides of the tipped part in their Starting position can be reduced. Because of this large diameter given a good precentering of the hollow body on the internal tools.

With the axial adhesion between the internal tools and the hollow body, that is created over the ends of the hollow body becomes the hollow body accelerated to the speed of the inner tools without the surface is stressed by friction on the inside of the hollow body.

To the surface on the inside of the hollow body even during the actual Molding process (teasing and flanging) from damage by To maintain slip, an additional radial frictional connection is provided between at least one inner tool and the hollow body.

Around the contour given by the two inner tools for teasing and flaring as stable as possible is after further training provided the two inner tools when axially moving together center to each other.

So in the event that only one inner tool is permanently driven in rotation a rapid acceleration of the other, non-driven inner tool according to a further development of the invention, that at the end of the axial movement of the inner tools inside the hollow body has a rotational force and / or Form fit between the two inner tools is produced.

• an getrennten Wellen angeordnet sind, deren Achsen miteinander fluchten,
• bei ihrer axialen Beweglichkeit einerseits eine voneinander entfernte Endlage einnehmen, die ein Einführen des Hohlkörpers zwischen die Innenwerkzeuge senkrecht zu ihrer gemeinsamen Achse ermöglicht und andererseits eine Endlage aufweisen, in der sie sich innerhalb des Hohlkörpers befinden,
• in ihrem zur Aufnahme des Hohlkörpers jeweils vorgesehenen Bereich (zylindrische Teile) den gleichen Durchmesser aufweisen, wobei dieser nur geringfügig kleiner ist als der Innendurchmesser des zylindrischen Hohlkörpers
• und mit ihrer jeweiligen Welle zusätzlich gegen axialen Druck verschiebbar gelagert sind,

daß in dem zur Aufnahme des zylindrischen Hohlkörpers vorgesehenen Bereich mindestens eines Innenwerkzeugs eine radial wirkende Spannvorrichtung vorgesehen ist, die gegen die Innenwandung des zylindrischen Hohlkörpers andrückbar ist
und daß das äußere Formwerkzeug zur Bildung des geneckten und gebördelten Endes soweit gegen die Profilkonturen der Innenwerkzeuge zustellbar ist, daß die beiden Innenwerkzeuge axial auseinander geschoben werden.The object on which the invention is based is achieved in a device of the type mentioned at the outset by
that the two interior tools

• are arranged on separate shafts, the axes of which are aligned with one another,
• in their axial mobility, on the one hand, assume a distant end position that enables the hollow body to be inserted between the internal tools perpendicular to their common axis and, on the other hand, have an end position in which they are located within the hollow body,
• have the same diameter in their area provided for receiving the hollow body (cylindrical parts), this being only slightly smaller than the inside diameter of the cylindrical hollow body
• and with their respective shafts are additionally mounted to be displaceable against axial pressure,

that in the area provided for receiving the cylindrical hollow body, a radially acting clamping device is provided, which can be pressed against the inner wall of the cylindrical hollow body
and that the outer mold for forming the tipped and flanged end can be advanced against the profile contours of the inner tools so that the two inner tools are pushed axially apart.

Due to the internal tools designed according to the invention, there is a complete and uniform support of the cylindrical hollow body, whereby the tipped and flanged area of the cylindrical hollow body can be trained very evenly. Because the inner tools are arranged on separate waves, these can be after teasing (local tapering or retraction of the side wall of the cylindrical Body, English: necking) on either side of the tipped hollow body be pulled out. This allows the tools to be proportionate large, at least larger than the inside diameter of the teased Area, be trained in what a good investment of the internal tools the inner wall of the cylindrical hollow body allows. Your outside diameter is only so much smaller than the inside diameter of the hollow body that an unimpeded movement of the inner tools into the hollow body and out of this is possible. Thanks to the radial clamping device of the at least one inner tool, which is against the inner wall of the cylindrical hollow body presses is a secure, slip-free hold of the Hollow body also accessible during the actual molding process. On uneven material intake can be avoided. Conveniently the clamping device must be operated mechanically or hydraulically.

A particularly expedient embodiment of the device consists in that when axially pushing the inner tools together Centering is given.

If only one inner tool is permanently driven in one device is, it is provided that the inner tools a non-positive and / or positive Have coupling for transmission of torques among each other.

Furthermore, it is advantageous for the axial detection of the hollow body if the Internal tools are provided with stop rings, the diameter of which is larger than the inside diameter of the cylindrical hollow body.

In a particularly advantageous development of the device, this is at least a rotatable inner tool with a separate, speed-controlled Drive motor connected. This allows the speed of the internal tools and possibly the hollow body regardless of the speed of the Adjust the rotating body and it can turn on one turn of the hollow body related infeed of the outer tool (mm / revolution of the hollow body) be adjusted or regulated. This allows different neck contours achieve optimal.

Fig. 1

eine erfindungsgemäße Vorrichtung im Längsschnitt,

Fig. 2

die Vorrichtung mit auseinandergefahrenen Innenwerkzeugen, von denen nur eins ständig angetrieben wird,

Fig. 3

eine Antriebsanordnung für das eine antreibbare Innenwerkzeug der Vorrichtung nach Fig. 2 in schematischer Darstellung und

Fig. 4

eine andere, mit einer Spannvorrichtung versehene Vorrichtung in einem auszugsweisen Längsschnitt.

The invention is explained in more detail below using an exemplary embodiment in conjunction with the drawing. Show it:

Fig. 1

a device according to the invention in longitudinal section,

Fig. 2

the device with the internal tools moved apart, only one of which is constantly driven,

Fig. 3

a drive arrangement for the one drivable inner tool of the device of FIG. 2 in a schematic representation and

Fig. 4

another, provided with a clamping device in a partial longitudinal section.

The device 50 shown in FIG. 1 has several stations 51 for formation a section to be teased and crimped one at both Ends of open cylindrical hollow body 1, in particular a can frame, on. The formation of a tucked and beaded section is fundamental in U.S. Patent 4,070,888, particularly in Figs. 10-14. The device 50 has a body firmly connected to the machine frame 21 52 with a central axis 53. There are two rotating bodies on the body 52 54, 55 rotatably supported about the axis 53. The evenly around axis 53 arranged stations 51 are located in both rotating bodies 54, 55 stored. The rotating bodies 54, 55 are each with a ring gear 56, 57 provided and can be synchronized by a (not shown) rotary drive be rotated. The central axis of rotation 53 can, as shown, be horizontal or be arranged vertically. The rotating bodies 54, 55 can also together form a body.

The formation of the section to be teased and crimped on both Ends of open cylindrical hollow body 1 is carried out by two of each opposite Sides insertable into the cylindrical hollow body 1 Molding tools 2 and 3 (hereinafter referred to only briefly as internal tools) and an axially fixed outer mold 4. In this device Axes 2A and 3A of inner tools 2 and 3 are aligned. The Internal tools 2 and 3 are with shafts 2W and 3W in sleeves 14, 15 arranged, which in turn are each rotatably supported in a holder 16, 17 are. The shafts are 2W, 3W with the associated sleeves 14 and 15, respectively e.g. via a spline connection 18 non-rotatably, but axially to each other slidably connected. The inner tools 2, 3 are one or several compression springs 8 and 9 are supported against the sleeves 14 and 15 in the sense that the spring force in each case towards the other inner tool 3 or 2 is directed.

The holders 16, 17 are each in a corresponding via a guide shaft 20 Guides 22, 23 of the rotating body 54, 55 are not rotatable in the direction of Axes 2A, 3A are slidably guided and are each driven by a linear drive Form of a control groove 24, 25 and one firmly connected to the body 52 engaging driver part 26 attached to the guide shaft 20, e.g. in the form of a guide roller, moving towards and away from each other. The greatest distance between the two inner tools 2, 3 must be apart be greater than the length of the hollow body to be teased and flanged 1 (see Fig. 2).

At the ends of the sleeves facing the respective inner tool 2 or 3 14, 15, an annular gear 28 is attached, which with a further (not shown) rotary drive is connected. The inner tool 2 has - seen in the direction of the inner tool 3 - one to the system one end of the hollow body to be teased and crimped 1 provided stop ring 5, a short cylindrical part 30, one tapering part 31 and a central recess 32. The inner tool 3 has - seen in the direction of the inner tool 2 - one to the system the other end of the hollow body 1 provided stop ring 6, a relatively long cylindrical part 33, the diameter of which is somewhat smaller is the inside diameter of the one to be teased and crimped Hollow body 1, a tapered part 34 and a centering projection 7. The cylindrical parts or sections 30, 33 serve to receive the teasing and flanging hollow body 1. Their outer diameters are the same size and so much slightly smaller than the inside diameter of the Hollow body 1 that the inner tools 2, 3 easily withdrawn from their Position (in which they are apart) in the for detection Retracted hollow body 1 coaxial to the axes 2A, 3A can be.

By rotating the inner tools 2, 3 about their own axes 2A and 3A the cylindrical hollow body 1 is also set in rotation. The Andes Internal tools 2 and 3 provided stop rings 5, 6 position the cylindrical hollow body 1 in the start phase of the necking and flanging process and grasp it with the positive connection given by the springs 8, 9. For mutual centering of the two inner tools 2 and 3 engages the centering approach 7 of the inner tool 3 into the recess 32 of the inner tool 2 a.

The outer mold 4 is designed as a profile roller and in a Rotating body 54 pivotally mounted swing arm 35 is mounted. The Swing arm 35 has a driver part 36 designed as a cam roller provided, the in a fixed with respect to the body 52 control groove 37 engages. Via the cam drive (control nut 37, driver part 36) the outer die 4 toward the coaxial axes 2A, 3A delivered or removed from them. If the outer mold 4 is delivered, the relevant wall section of the cylindrical hollow body pressed towards the tapered sections 31, 34. Becomes the outer mold 4 after it (with the interposition of the wall of the Hollow body 1) rests on the tapered sections 31, 34 in the direction of axes 2A, 3A, the inner tools give way 2, 3 apart against the force of the springs 8, 9 accordingly. there the degree of tapering (necking) can be changed or adjusted become. At the same time, the outer end of the hollow body 1 forms when in contact and sliding on the tapered end 31 an outward Flanged flange, so that there is an overall teased and flared Forms edge section on the hollow body 1.

In the device shown in Fig. 4 with internal tools 2 ', 3' and an outer mold 4 ', the inner tool 3' has a radially acting Tensioning device 10 with a tensioning piston 11 (hereinafter only briefly Called piston), a cylinder 12 receiving the piston and one Tension chamber 13 on. The piston 11 is in the direction of a compression spring 38 pressed on the inner tool 2 '. If the inner tools 2 ', 3' for Receiving a hollow body 1 are moved apart axially, is the piston 11 pushed so far out that a shoulder or projection 39 from the inner tool 3 'projects outwards.

The clamping chamber 13 is a cavity in the inner tool 3 'through a very thin outer wall 40 is formed. The clamping chamber 13 is above a radial bore 41 in line connection with the cylinder 12. Both rooms 12, 13 and the line connection 41 are with a liquid pressure medium filled. If now the inner tools 2 ', 3' for receiving a hollow body 1 move together, the piston 11 over the projection 39 from one part the end face of the inner tool 2 'pressed into the cylinder 12. The displaced pressure medium enters the clamping chamber 13 and expands the thin wall section 40 to the outside, as shown in FIG. 4 somewhat is exaggerated. The flared outer wall portion 40 is gripped thereby the wall of the hollow body 1 and thus creates a good friction connection between the inner tool 3 'and the hollow cylinder 1, making an optimal Carriage is guaranteed.

In the embodiment shown in Fig. 2, only the right inner tool 3 driven, which preferably, as with the inner tool 3 ' described, is provided with a clamping device 10. Accordingly, the Sleeve 15 provided with a gear 28. The sleeve 14 'of the left inner tool 2 has no such gear.

If the internal tools are moved together via the control grooves, the centering lug 7 of the inner tool 3 slides into the recess 32 of the Inner tool 2. At the end of the moving together, the centering shoulder presses 7 against a friction lining 43 arranged in the recess 32. This The friction lining and the centering projection 7 together form a frictional connection Coupling between the two inner tools, through the inner tool 2 is driven each time the inner tool 3 moves together.

Fig. 3 shows a drive for the gear 28, which is assigned to the inner tool is. The gear 28 and the holder 17 are in the working position in dash-dotted lines and in the retracted position in extended Lines shown. A motor 60 attached to the body 52 also drives a gear 62 with an internal toothing 63 on its pinion 61. The gear 62 also has an external toothing 64 which engages with the gear 28 stands. Since the gear 28 is displaced axially, the external toothing has 64 a corresponding width.

The motor 60 is speed-controlled, regardless of the speed of the Rotating bodies 54, 55. This allows the control nut 37 to be used Infeed of the outer tool 4 with respect to one revolution of the Internal tools 2, 3 and the hollow body 1 vary.

Claims (10)

1. Method of forming a necked and flanged section at one end of a bilaterally open cylindrical hollow body (1), in particular of a can body, by means of two inner tools (2, 3; 2', 3') and one outer tool (4), whereby at least one inner tools is driven for rotation and the inner tools (2, 3; 2', 3') are axially displaceable in relation to the hollow body (1) into its inner and afterwards the outer tool (4) is radially displaced towards the hollow body (1) which is arranged on the inner tools in such a manner that its sector provided therefor is pressed in a concave circuit contour (31, 34) formed mutually by the both inner tools (2, 3; 2', 3') are moved back into their starting position before the shaping of the hollow body (1), characterized by the following steps:

   both inner tools (2, 3; 2', 3') entering the hollow body (1) by approaching the inner tools from a distant position

   axial fixing and frictional grasping of the hollow body (1) by the inner tools (2, 3; 2', 3') when their mutual distance is smallest

   generating an additional, radially acting force of friction between at least one inner tool (3') and the hollow body (1)

   and shaping pressure of the outer tool (4) onto the hollow body (1).
2. Method according to claim 1, characterized in that the both inner tools (2, 3; 2', 3') are centered when axially approaching.
3. Method according to claim 1 or 2, characterized in that the end of the axially approaching of the inner tools (2, 3; 2', 3') a frictional and/or shape contact is effected between at least one inner tool (3) driven for rotation and the other inner tool.
4. Device for carrying out the method according to one of the claims 1 to 3, comprising for forming necked and crimped ends of a cylindrical hollow body (1) two axially movable inner tools (2, 3; 2', 3'), at least one of them being driven for rotation and having a contour corresponding the necked and crimped end and an outer tool (4) radially displaceable in relation to the inner tools (2, 3; 2', 3'),characterized in that the both inner tools (2, 3; 2', 3')

   are mounted on separate shafts (2W, 3W) being axially aligned (2A, 3A)

   when axially an inserting of the hollow body (1) between the inner tools (2, 3; 2', 3') prependicular to their common axis (2A, 3A) and having a second end position in which the inner tools are situated inside the hollow body (1)

   having the same diameter in the section (cylindrical parts 30, 33) provided for the reception of the hollow body (1), whereby the diameter is only a little bit smaller than the inner diameter of the hollow body (1),

   running in bearings and being additionally displaceable with the respective shaft (2W, 3W) against axial pressure (springs 8, 9), that in the section for reception of the hollow body (1) at least one inner tool has a radially effective clamping device (10) which can be pressed against the inner wall of the hollow body (1) and that for forming a necked and crimped end the outer shaping tool (4, 4') can be moved to such an extend against the profile contours of the inner tools (2, 3; 2', 3') that both inner tools (2, 3; 2', 3') are axially pushed apart from one another.
5. Device according to claim 4, characterized in that one inner tool (3) has a centering projection (7) and the other inner tool (2) has a corresponding recess (32), and that the inner tools (2, 3; 2', 3') can be axially driven in a position wherein the centering projection (7) enters into the recess (32).
6. Device according to claim 4 or 5, characterized in that the inner tools (2, 3; 2', 3') have a frictional and/or shape contact gear for transmitting torques mutually.
7. Device according to one of the claims 4 to 6, characterized in that the inner tools (2, 3; 2', 3') are provided with annular abutment flanges (5, 6) whose diameter is greater than the diameter of the cylindrical hollow body (1).
8. Device according to one of the claims 4 to 7, characterized in that the clamping device (10) can be activated mechanically or hydraulically.
9. Device according to one of the claims 4 to 8, characterized in that at least one inner tool (3) driven for rotation is connected to an own speed governed drive motor (60).
10. Device according to one of the claims 4 to 9, characterized in that the inner tool (3, 3') is driven for rotation via the clamping device.

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