DE102008038263B4 - Transfer press with CUP stage - Google Patents

Abstract

Transfer press, consisting of a press frame, a press table, a main tappet, a plurality of step tools and a CUP-stage for forming a CUP part, characterized in that the CUP step a separate and independent of the drive for the main tappet (3) and the step tools (5; 6) equipped drive (8), said drive (8) is associated with a planetary roller screw (9) which drives a spindle nut (12) in a CUP tappet (13), which guided linearly in guides (14) becomes.

Description

The invention relates to a transfer press, comprising a press frame, a press table, a main ram, a plurality of step tools and a CUP stage for forming a CUP part.

For various technical applications, objects with different geometric contours are formed from sheet metal structures by multi-stage forming. For this purpose, separate presses can be used in the production process for each forming step, which are linked together to form a press line. Such a chaining of individual machines is predominantly realized for large-area or highly contoured components, for example in the automotive industry for the production of body parts. If the components to be produced are smaller, as an alternative to a press line individual forming stages can be integrated in a common structural unit, with technical solutions in this regard being known as a stepped press or transfer press.

The transfer presses predominantly have a crank or joint drive for a press ram and several successive step tools. Thus, starting from a blank over several intermediate forms to the final shape several forming stages can be integrated in a press, in practice, six or more forming stages have been realized. The feed and transport devices for the continuous transfer of the workpieces are often adapted to the kinematics of the main tappet via a cam control.

The transfer presses are sometimes assigned so-called CUP stages in order to produce the blank cutting operation in one stage and then a first drawing operation. In this case, a cutter arranged on the press ram cuts a blank from the fed strip material. The feed takes place via a feed, which is arranged offset by 90 ° to the transfer movement in front of or behind the press, wherein the strip material can be fed by means of a zig-zag or pivoting movement. The cut-out blank is first held in the bottom dead center (UT) via a detent of the main tappet. Thereafter, the blank is pressed with a second additional drive via a guided plunger, to which a drawing punch is attached, in a deeper than the cutting plane lying die. The thus pulled sleeve is called CUP. This CUP part is stripped in the transfer plane and transported with the transfer to the next drawing stage.

The drive for the CUP stage has hitherto been via cam or lever drives, which are firmly coupled to the movement of the main tappet. This fixed coupling requires complicated adjustments to the CUP tool when changing the diameter of blank or CUP part, as well as changing the height of the CUP part. For a higher CUP stroke, the entire CUP drive must be changed. However, this is unacceptable in economic terms. Substantial changeover times and additionally necessary tool parts or necessary modifications of the CUP drives, levers and curve elements make a quick and flexible conversion of such a press not possible. In addition, only parts of a certain length can be pulled by the fixed stroke of the cam drives. The changeover effort to change the drive curves is very high, because the entire drive shaft of the machine must be removed and a new drive curve for the CUP stage must be installed. It is important to pay attention to a defined ratio to the drive of the main tappet, because the movements of main tappet and CUP tappet must run synchronized with each other. Furthermore, a return movement of the CUP ram up essential to release the supplied strip material. In this case, the drawing punch must drive out of the belt to start the feeding movement of a roll feed for the strip material. Fast retracting movements of the pull ram provide advantages, especially at high stroke rates, because this increases the available travel time for the tape feed.

The object of the invention is to provide a transfer press with a CUP stage, which can be converted with a small time and handling effort for different geometries of blanks and / or CUP parts.

This object is achieved by the CUP-stage has a separate and designed independently of the drive for the main tappet and the step tools drive, this drive is associated with a planetary roller screw that drives a spindle nut in a CUP tappet, which is guided linearly in guides , Advantageous embodiments are the subject of subclaims, whose features are described in more detail in the embodiment.

The CUP tappet is associated with a freely programmable independent drive for which preferably an electric motor is used. As an alternative, the use of a hydraulic drive is proposed. Regardless of its specific configuration, this drive drives a planetary roller screw directly or indirectly (for example, via a toothed belt). The planetary roller screw, which has a spindle nut in the CUP Pushes ram is rotatably arranged. The linear movement of the CUP ram generates the drag operation. In this case, a part-dependent tool part is attached to the lower end of the CUP tappet.

By using the planetary roller screw very large forming forces can be applied. This forming forces are effectively derived via a strong axial bearing of the spindle in the press frame. In addition, high speeds and consequently high stroke rates are possible. Due to the tight guidance of the CUP tappet can be dispensed with a further leadership of the drawing tool.

With the freely programmable electric or hydraulic drive, it is possible to follow any mechanical curves, to establish the synchronization of the CUP stage to the main tappet or to release them again in a certain travel range. The stroke length and stroke of the CUP tappet can be changed via simple programming. Furthermore, a very fast backward movement of the pull ram is possible.

As a result of the inventive separation of the drive assembly for the CUP stage from the drive for the main ram and the step tools, the transfer press can be converted with a small amount of time and handling effort for different geometries of round blanks and / or CUP parts. In this case, the optimization of existing tools and a quick conversion to new parts are possible in an advantageous manner, without an additional installation effort or the otherwise necessary change of components.

An embodiment of the invention is illustrated in the drawing and will be described below. Show it:

1 the basic structure of a transfer press according to the invention in side view

2 the basic structure of the transfer press in plan view

The apparent from the drawing transfer press consists of a press frame 1 , a press table 2 , a main pestle 3 with ram guides 4 and several step tools, one of which is a tool top 5 and a tool base 6 are shown. Furthermore, the transfer press comprises an additional CUP stage.

The one on a console 7 The press-supported CUP stage has a separate and independent drive for the main ram 3 and the step tools designed drive 8th for a planetary roller screw 9 on. According to the drawing, this separate drive is a freely programmable electric servomotor 8th designed. Alternatively, a design as a hydraulic drive is possible.

With the separate drive 8th can the planetary roller screw 9 driven directly or indirectly. In the drawing, a variant is shown with indirect drive, wherein the connection between servo motor 8th and planetary roller screw 9 via a toothed belt 10 he follows.

The planetary roller screw 9 is an axial bearing 11 assigned. About this axial bearing 11 can the forming forces occurring effectively in the press frame 1 be derived.

The planetary roller screw 9 drives a spindle nut 12 in a CUP tappet 13 who is in guides 14 is guided linearly. At the Ronde associated end portion of the CUP tappet 13 there is a tool holder 15 , In this tool holder 15 a tool part is attached, the contour of which is to be formed each CUP part 16 is tuned.

The transfer press further comprises an assembly 17 for the parts transfer. In the cutting plane 18 is the tape feed.

In the operation of the transfer press is one of the supplied strip material in the cutting plane 18 cut Ronde first held in the bottom dead center. After that, this round plate is over the CUP tappet 13 that's about servomotor 8th , Timing belt 10 , Planetary roller screw 9 and spindle nut 12 powered and in guides 14 is guided, with the at the tool holder 15 attached tool part in a deeper than the cutting plane 18 lying drawing die for forming a CUP part 16 pressed. Thereafter, the transport and the alignment of the CUP part take place 16 Components to be manufactured in further forming stages by the assembly 17 ,

LIST OF REFERENCE NUMBERS

1

press frame

2

press table

3

main slide

4

ram guides

5

Upper die

6

Tool part

7

console

8th

drive

9

Planetary roller screw spindle

10

toothed belt

11

axial bearing

12

spindle nut

13

CUP-ram

14

guides

15

tool holder

16

CUP-part

17

parts transfer

18

cutting plane

Claims (8)

Transfer press, comprising a press frame, a press table, a main ram, a plurality of step tools and a CUP step for forming a CUP part, characterized in that the CUP step a separate and independent of the drive for the main ram ( 3 ) and the step tools ( 5 ; 6 ) designed drive ( 8th ), this drive ( 8th ) a planetary roller screw ( 9 ) associated with a spindle nut ( 12 ) in a CUP tappet ( 13 ) in guided tours ( 14 ) is guided linearly. Transfer press according to claim 1, characterized in that the planetary roller screw spindle ( 9 ) an axial bearing ( 11 ) for deriving the forming forces in the press frame ( 1 ) assigned. Transfer press according to claim 1, characterized in that the separate drive ( 8th ) the planetary roller screw ( 9 ) drives directly. Transfer press according to claim 1, characterized in that the separate drive ( 8th ) the planetary roller screw ( 9 ) indirectly drives. Transfer press according to claim 4, characterized in that the separate drive ( 8th ) the planetary roller screw ( 9 ) via a toothed belt ( 10 ) drives. Transfer press according to claim 1, characterized in that the separate drive ( 8th ) for the planetary roller screw spindle ( 9 ) is designed as a freely programmable electric motor. Transfer press according to claim 1, characterized in that the separate drive ( 8th ) for the planetary roller screw spindle ( 9 ) is designed as a freely programmable hydraulic drive. Transfer press according to claim 1, characterized in that at the end of the CUP tappet associated with the blank ( 13 ) in a tool holder ( 15 ) a tool part is fixed, the contour of which in each case to be formed CUP part ( 16 ) is tuned.

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