EP0865845A1 - Method for holding together split molds or dies subjected to internal pressure and device for carrying out the method - Google Patents

Abstract

Top and bottom tools (7, 8) between the top and bottom plates (1, 2), which are kept apart by distance pieces (3), are clamped together by connector elements (5). One or several membrane-like disks (4) with a fixing flange (21) and/or a fixing ring (22) are/is located below the top and/or above the bottom plate, with a hydraulically tight seal formed between the plate (1, 2) and the disk (4). The top and/or bottom plate (1, 2) are/is provided with a connection (6) for delivery of a high-fluid into the space between the plate and the disk (4). The top and bottom tools form a tool block which together with a workpiece (24) can be slid into and out of the space between the plates (1, 2).

Description

The invention relates to a method for holding two together shared tools or dies that are subjected to internal high pressure are, according to the preamble of claim 1 and to a device Preamble of claim 2, preferably for performing the method.

Tools, in particular for hydroforming (IHU) or for die casting, exist with regard to loading and unloading Workpieces from an upper and a lower tool, which during the Pressurization must be held together. A conventional press design, e.g. For die forging or sheet metal forming, whereby the Lower tool is firmly connected to the press stand and that on Press ram attached upper tool performs a relatively large stroke. This stroke must be so large that the workpiece is loaded and unloaded can and that even the tools or dies are regular can be cleaned. These are the cycle times correspondingly long because the processes of loading, closing the dies, Forming, opening the dies, unloading and cleaning in general only can be executed one after the other. Because of the very large stroke of the Upper tool there are versions in which the idle stroke with a long stroke and small force and the closing stroke with short stroke and large force over separate facilities are applied. The tappet guides are with the known devices arranged relatively far from the tool and the press construction naturally builds very large. With manual loading the press is also mainly due to the high pressures at Internal high pressure forming a high effort in terms of occupational safety to operate.

DE 195 13 444 A1 describes a method and an apparatus for hydrostatic cold forming of hollow profiles Hydroforming known, one of the desired forms of Pressure build-up curve corresponding to the workpiece for the deformation required workpiece pressure is realized and at the same time dependent the locking forces of the surrounding internal pressure of the sheet metal body Tool set in hydroelectronically controlled pressure cylinders Surface sections are applied. The printing cylinders are as Membrane cylinders with a small volume and thus lower Compression amount trained and so with differentiated pressure applies that depending on the respective internal pressure the corresponding one ideal closing force can be applied locally. For loading and unloading However, it is necessary that a pressure cushion is attached to which the individual printing cylinders are arranged, is pulled out of the press, so that the upper part of the tool is lifted by auxiliary cylinders and that Workpiece can be removed from the press. Then be conversely, the workpiece is placed on the lower part of the tool Lowered upper part of the tool, the pressure pad back into the press drove in and pressurized the pressure cylinder so that the Hydroforming can take place. The time between two Forming processes is due to the large number of work steps for loading and Unloading the workpieces for a long time.

The invention has for its object a generic method and / or propose a device, such problems not occur.

The solution to this problem is described in claims 1 and 2. The Subclaims 2 and 4 to 6 contain useful additional suggestions.

In the method according to the invention, the tools are not as in a common press design with the help of hydraulic cylinders with large Hub held together, but the arrangement of one or several membrane-shaped discs on the bottom and / or top of the Plates. These disks become elastic and hydraulically tight with the plates connected. When the space between plate and Disc before the forming process begins, the disc becomes solid with relative small stroke pressed against the top or bottom of the tools. Of the Gap is provided with appropriate holes and connections connected to the hydraulic system. Due to the small stroke and a small amount of space is sufficient. Hydraulic fluid to generate the required contact pressure on the tools. The two tools (lower and upper tool) with the corresponding in Recesses arranged workpiece are a tool block summarized and are as a whole after releasing the contact pressure on the tools laterally between those at a fixed distance from each other arranged plates pulled out and over a transport system appropriate loading and unloading stations promoted. When using multiple Tool blocks can be used immediately after removing one tool block another tool block with one still added to the finished workpiece machining workpiece in the holding device between the Plates are inserted. It is advantageous if the removal of the Do not work the tools within the holding device be raised at least by the height of the finished workpiece have to. This process can take place in a separate unloading station. The means for the holding device that the stroke of the Membrane-shaped disc only needs to be large enough for the tool block can be moved in and out unhindered. To make this easier Driving process, it has proven to be beneficial to use the tool block moving from rollers on appropriate transport tracks.

To realize a possibly additionally required relative stroke During the forming process, the lower and / or upper tool can be inserted hydraulic ram can be integrated, which act directly on the workpiece can.

To fix the two tools on each other are preferably perpendicular pin-like guide elements are provided on the longitudinal axis thereof corresponding holes or recesses of the two tools are. These guide elements can also absorb lateral forces so that the the two plates and the spacers arranged between them such forces are burdened. The holding device is similar arranged like a machine tool in a protective housing that offers protection especially when using the high hydraulic pressures.

Fig. 1

einen Schnitt durch die erfindungsgemäße Zusammenhaltevorrichtung

Fig. 2

eine Draufsicht auf die Vorrichtung nach Fig. 1

Fig. 3

eine Draufsicht auf die Vorrichtung nach Fig. 1 und 2 und ein Transportsystem für die Werkzeugblöcke.

The invention is explained in more detail, for example, with reference to the attached FIGS. 1 to 3. Show it

Fig. 1

a section through the holding device according to the invention

Fig. 2

a plan view of the device of FIG. 1st

Fig. 3

a plan view of the device of FIGS. 1 and 2 and a transport system for the tool blocks.

Lanzen abdichten", Nachstauchen" und Bauteil aufblasen" ausführen. Diese Axialzylinder 9,10,11 fahren nach dem Klemmen der Werkzeuge 7,8 mit Hilfe der Scheibe 4 bis zum Werkstück 24 vor. Die Anordnung der Axialzylinder 9,10,11 richtet sich nach der Form der herzustellenden Teile. In Fig. 3 sind z.B. zwei Axialzylinder 9,11 und in Fig. 2 drei Axialzylinder 9,10,11 dargestellt. Zur Positionierung der Werkzeuge 7,8 sind diese über Führungen 23 miteinander verbunden. Diese Führungen 23 nehmen auch Querkräfte auf, die damit nicht die Plattenkonstruktion 1,2,3 belasten. Die über die Führungen 23 zu einem Werkzeugblock 20 zusammengefügten Werkzeuge 6,7 bilden innen einen Raum, der im wesentlichen die Form des herzustellenden Werkstückes 24 besitzt. Der Werkzeugblock 20 mit dem darin angeordneten Werkstück 24 wird als Einheit auf Rollen 12 und auf Transportbahnen 18 von der Zusammenhaltevorrichtung zu verschiedenen Stationen 13 bis 16 zur Be- und/oder Entladung der Werkstücke 24 transportiert. Dieser Transport kann durch z.B. nicht dargestellte externe Hydraulikzylinder oder andere Transporteinrichtungen erfolgen. Nach dem Umformvorgang in der Zusammenhaltevorrichtung wird die Platte 4 entlastet, wodurch sich diese vom Werkzeug 6,7 abhebt und den Werkzeugblock 20 freigibt. Dieser wird zwischen den Platten 1,2 herausgezogen und nach Fig. 3 z.B. über die Transportbahn 18 zu einer Entladestation 13 gebracht, wo die beiden Werkzeughälften voneinander getrennt werden und das fertige Werkstück entnommen werden kann. Anschließend wird der Werkzeugblock 20 weitertransportiert zur Beladestation 14. Dort erfolgt die Bestückung mit einem neuen Rohteil. Anschließend wird der Block 20 in Beladebereitschaft (Station 15) gebracht. Falls die Vorrichtung aufgrund der Anordnung der Axialzylinder 9,10,11 (vgl. Fig. 2) nur von einer Vorderseite zugänglich ist, wird eine zusätzliche Station 16 vorgesehen, die dann abwechselnd mit der Station 14 die Be- und Entladung nur von einer Seite vornimmt. Die Zusammenhaltevorrichtung kombiniert mit dem Werkzeugblocktransportsystem nach Fig. 3 arbeitet kontinuierlich. Die Vorrichtung ist in einem Schutzgehäuse 19 ähnlich wie bei einer Werkzeugmaschine aufgestellt und dadurch allseitig geschützt.The device according to FIG. 1 consists of a lower plate 2 and an upper plate 1, which are kept at a distance by parallel spacers 3 and are clamped together by connecting elements 5, for example screws or tie rods. A membrane-shaped disk 4, which is very thin in relation to this plate, is arranged below the upper plate 1. The disc 4 is provided on the outer edge with a mounting flange 21 which, with the aid of a mounting ring 22, produces a hydraulically sealed connection between plate 1 and disc 4. The upper plate 1 is provided with a connection 6 through which a liquid medium is passed under high pressure between the plate 1 and the disc 4 during the forming process. As a result, the membrane-shaped plate 4 lowers against the tool composed of the upper tool 8 and the lower tool 7 and keeps this divided tool closed during the forming process. A hydraulic ram 17 is integrated in the lower tool 7 in order to realize an additional relative stroke during the forming. In the case of larger workpieces 24 and the associated larger dimensions of the tools 7, 8, a plurality of membrane-shaped disks 4 can also be arranged next to one another or act on the surface of the tool at different points. In order to introduce the required internal pressure into cavities of the workpiece 24 for the actual hydroforming, one or two or more axial cylinders 9, 10, 11, which perform the known functions, are laterally fastened in the spacers 3

Seal lances ", Upsetting "and Inflate the component ". After the tools 7, 8 have been clamped, these axial cylinders 9, 10, 11 move with the aid of the disk 4 to the workpiece 24. The arrangement of the axial cylinders 9, 10, 11 depends on the shape of the parts to be produced. 3 shows, for example, two axial cylinders 9, 11 and three axial cylinders 9, 10, 11 in Fig. 2. For positioning the tools 7, 8, they are connected to one another via guides 23. These guides 23 also absorb transverse forces, which are thus do not load the plate construction 1, 2, 3. The tools 6, 7 joined together via the guides 23 to form a tool block 20 form a space on the inside which essentially has the shape of the workpiece 24 to be produced, the tool block 20 with the workpiece 24 arranged therein transported as a unit on rollers 12 and on transport tracks 18 from the holding device to various stations 13 to 16 for loading and / or unloading the workpieces 24. This transport can be carried out by h For example, external hydraulic cylinders or other transport devices, not shown, are carried out. After the forming process in the holding device, the plate 4 is relieved, whereby it stands out from the tool 6, 7 and releases the tool block 20. This is pulled out between the plates 1, 2 and, according to FIG. 3, is taken, for example, via the transport path 18 to an unloading station 13, where the two tool halves are separated from one another and the finished workpiece can be removed. Subsequently, the tool block 20 is transported on to the loading station 14. There, the assembly takes place with a new blank. Then the block 20 is brought ready for loading (station 15). If, owing to the arrangement of the axial cylinders 9, 10, 11 (cf. FIG. 2), the device is only accessible from a front side, an additional station 16 is provided, which then alternates with the station 14 for loading and unloading only from one side makes. The holding device combined with the tool block transport system according to FIG. 3 works continuously. The device is installed in a protective housing 19 similar to a machine tool and is therefore protected on all sides.

• sehr einfache Konstruktion, wenige Teile, keine herkömmliche Presse erforderlich
• Verkürzungen der Taktzeit durch Trennen der Vorgänge Reinigen, Beladen, Schließen der Werkzeuge, Umformen, Öffnen der Werkzeuge, Entladen
• automatischer Ablauf durch Werkzeugtransportsystem
• hoher Arbeitsschutz durch Schutzgehäuse
• Wegfall von Werkzeugwechselzeiten.

In summary, the following advantages result for the method according to the invention and the device for carrying out the method:

• very simple construction, few parts, no conventional press required
• Shortening the cycle time by separating the processes cleaning, loading, closing the tools, forming, opening the tools, unloading
• automatic process through tool transport system
• high work protection through protective housing
• Eliminate tool change times.

Reference symbol list:

1

top plate

2nd

lower plate

3rd

Spacers

4th

membrane-shaped disc

5

Connecting elements, e.g. Screws or tie rods

6

Connection for liquid medium

7

Lower tool

8th

Upper tool

9,10,11

Cylinder (axially movable)

12th

roll

13-16

Stations for loading and / or unloading the workpieces 24

17th

hydraulic ram for additional relative stroke

18th

Transport lanes for 20

19th

Protective housing

20th

Tool block

21

Mounting flange on the outer edge of 4

22

Fastening ring for 21 on 1

23

Guide element for positioning 7 and 8

24th

workpiece

Claims (6)

Method for holding together two divided tools or dies that are subjected to internal pressure, whereby a) upper and lower tools between an upper plate and a lower plate, which are kept apart by parallel spacers, are clamped by connecting elements, b) to hold the tools together, one or more membrane-shaped disks are arranged on the underside of the upper plate and / or on the upper side of the lower plate, which are pressed hydraulically and / or mechanically against the upper and / or lower tool during the internal pressurization of the tools, c) for loading and unloading the tool block consisting of lower and upper tools, the disks are relieved and / or withdrawn to the plates, and d) outside of the holding device in which the tools are subjected to internal pressure, the loading and unloading of the workpieces takes place in or out of the tool block in one or more stations. Device for holding together two divided tools or dies that are subjected to internal pressure, preferably for carrying out the method according to claim 1, wherein a) upper and lower tools (7, 8) between an upper plate (1) and a lower plate (2), which are kept at a distance by parallel spacers (3), can be clamped by connecting elements (5), b) one or more diaphragm-shaped disks (4) are arranged below the upper and / or above the lower plate (1, 2), which have a hydraulically sealed connection with a circumferential outer fastening flange (21) and / or a fastening ring (22) Form the plate (1,2) and the disc (4), c) the upper and / or lower plate (1, 2) is provided with connections (6) through which a liquid medium can be introduced under high pressure into the intermediate space between plate (1, 2) and disc (4) during the forming process and d) upper and lower tools (7, 8) can be inserted as a tool block (20) with a workpiece (24) arranged therein for the forming process between the plates (1, 2) and can be removed after the forming process. Device according to claim 2, characterized in that at least one of the tools (7, 8) has a hydraulic tappet (17) integrated in it, which during the forming process has an additional relative stroke between the plate (1, 2) and the tools (7, 8). generated. Device according to claim 2 or 3, characterized in that the upper and lower tools (7, 8) are positioned relative to one another via guide elements (23). Device according to claim 2, 3 and 4, characterized in that the tool block (20) is mounted on rollers (12). Device according to at least one of claims 2 to 5, characterized in that the holding device is arranged in a protective housing (19).

Images