Device for stretching metal semi-finished product in form of single sheet along stretching section having stretching frame and method for stretching metal semi-finished product using such device

Abstract

The invention relates to a device for stretching a metal semi-finished product in the form of a single sheet along a stretching section having a stretching frame (2), comprising: a pressure column (7, 8) extending in the axial direction of the stretching section; a first clamping head (3), in which a first narrow side of the semi-finished product to be stretched can be clamped and which can be axially displaced by means of a stretching cylinder (5, 6); the device according to the invention is characterized in that at least one axial input device and one axial output device of the stretching frame (2) are provided, and the clamping heads (3, 4) are designed to clamp a first narrow edge of the semi-finished product to be stretched, and in that the clamping heads (3, 4) are designed to clamp a second narrow edge of the semi-finished product to be stretched. In this way, the semi-finished product to be stretched can be axially guided through at least one, preferably through the two chucks (3, 4).

Description

[0001] This application is a divisional application of an international application entering the Chinese national phase, with an application date of September 25, 2020, an international application number of PCT / EP2020 / 076926, a national application number of 202080071096.4, and a title of "Device for stretching a metal semi-finished product in the form of a single sheet along a stretching section with a stretching frame and method for stretching a metal semi-finished product using the device". Technical Field

[0002] The invention relates to a device for stretching a metal semi-finished product in the form of a single sheet along a stretching section with a stretching frame, the device comprising: a pressure column extending in the axial direction of the stretching section; a first chuck in which a first narrow edge of the semi-finished product to be stretched can be clamped and which can be axially displaced by means of a stretching cylinder; and a second chuck in which a second narrow edge of the semi-finished product to be stretched can be clamped.

[0003] The invention also relates to a method for stretching a metal semi-finished product in the form of a single sheet along a stretching section using the above-mentioned device. Background Art

[0004] Sheet stretching machines and sheet stretching methods of the above type are known in the prior art, for example, from the published documents DE 10 2016 105 306A1 and DE 10 2015 214 207A1.

[0005] Such sheet stretching machines typically have two chucks to be aligned with each other, which can be displaced in opposite directions to apply a tensile force oriented along the stretching direction. The sheet stretching machine is used for stretching and / or straightening rolled or pressed stretch objects, in particular for stretching and / or straightening individual sheets or plates clamped or wedged in the chucks. Depending on the configuration of the sheet stretching machine, the two chucks can be moved during stretching. Of course, a layout is generally obtained in which there is a fixed chuck and a chuck displaceable relative thereto. Such a layout is known, for example, from DE10 2015 14 207A1, where the movable chuck can be displaced via a hydraulic stretching cylinder and a stretching rod, while the fixed chuck includes a slide block that can be locked relative to the pressure column element of the stretching frame. Locking is desired at different locations because different operations are performed when stretching individual sheets or plates compared to the case of quasi-continuous straightening of sheets wound into coils with different workpiece lengths or sheet lengths or plate lengths, and the stretching frame must be set accordingly. Methods and devices for straightening metal sheets wound into coils are known, for example, from EP 1 923 150B1 and US2002 / 0104360A1.

[0006] Known sheet stretching machines load and unload sheets from above by means of a lifting device. The chuck must first be set to a size larger than the size of the sheet to be stretched. Then, the chucks are moved together and convey the sheet to a clamping device integrated into the chuck. For unloading, after the stretching process, the clamp is opened and the chuck is moved again to a size larger than the size of the stretched sheet. The disadvantage of this processing method is that a relatively large stroke of the stretching cylinder is required because the chuck must be set to a size larger than the length of the sheet to be stretched. In addition, the non-productive time of the stretching process is long compared to the time required for stretching. Overall, the required cycle time is relatively large. Summary of the Invention

[0007] The object on which the present invention is based is to provide a sheet stretching machine of the type described at the beginning and a corresponding method, in which the non-productive time is reduced and thus the cycle time is optimized overall.

[0008] This object is achieved by a device having the features of claim 1. The object on which the present invention is based is also achieved by a method having the features of claim 7. Advantageous designs of the present invention result from the dependent claims.

[0009] According to one aspect of the present invention, there is provided a device for stretching a metal semi-finished product in the form of a single sheet along a stretching section having a stretching frame. The device includes: a pressure column extending in the axial direction of the stretching section; a first chuck in which a first narrow edge of the semi-finished product to be stretched can be clamped and the first chuck can be axially displaced by means of a stretching cylinder; and a second chuck in which a second narrow edge of the semi-finished product to be stretched can be clamped. The device according to the present invention or the sheet stretching machine according to the present invention is characterized in particular in that at least one axial input device and an axial output device of the stretching frame are provided, and the chucks are configured such that the semi-finished product to be stretched can be axially guided through at least one, preferably through two chucks. Thus, the sheet can be input and output in the direction of the force action during stretching.

[0010] Loading and unloading the device from above by means of a crane is thus eliminated. The input and output of each sheet can be fully automated. The cycle time required for stretching each sheet is drastically reduced. In addition, the length of the stretching cylinder is reduced, whereby the sheet stretching machine according to the present invention can have a smaller overall size.

[0011] Preferably, at least one chuck has at least one chuck opening that is open in the stretching direction, such that the sheet to be stretched can be axially moved into the relevant chuck opening from the outside. The chuck openings preferably face away from each other in the axial direction of the stretching section in the stretching frame, and at least one chuck is configured such that the sheet can be guided through the relevant chuck so that the sheet can be positioned between the chucks.

[0012] In the sheet stretching machine according to the invention, it can be proposed that during the stretching or elongation of the sheet, both chucks can move. Preferably, the second or the first chuck is locked or can be locked relative to the pressure column element of the stretching frame. For this purpose, the stretching frame can have, for example, a locking device corresponding to that described in DE 10 2015 214 207 A1.

[0013] The chuck can have, in a known manner and method, means for clamping and / or wedging the workpiece or the sheet.

[0014] The axial input device advantageously includes an input roller path and the axial output device includes an output roller path. The input roller path and / or the output roller path can include driven rollers, such that the conveyance of the sheet and the output of the sheet can be carried out in the axial direction of the stretching section.

[0015] Preferably, the input roller path and / or the output roller path are height-adjustable, so that the sheet can be positioned at the middle height level of the sheet stretching machine or the stretching plane during loading or unloading. Generally, the sheet to be stretched is usually provided on a roller path above the ground. The input roller path can receive the sheet to be stretched at the height level where the sheet is provided. Then, the input roller path is guided past the relevant chuck and set at the corresponding height level. The stretched sheet is transported away in a similar manner and method by means of the output roller path.

[0016] Preferably, first and second loading devices are provided, wherein the first loading device is arranged on the first chuck and the second loading device is arranged on the second chuck, and the loading devices each include a driven roller. The loading devices serve to position the sheet to be stretched at a height at which the sheet is centered on the longitudinal axis and the sheet is driven.

[0017] The sheet is preferably transported from below by means of driven rollers and a pressing roller acting from above. The loading devices can each have a centering unit. For example, the centering unit can be configured in the manner and method described in DE 10 2016 105 306 A1, and for the purpose of disclosure, this document is hereby incorporated by reference in its entirety.

[0018] In an advantageous variant of the device according to the invention, it is proposed that at least one transverse straightening press is arranged between the first chuck and the second chuck. The transverse straightening press can be configured such that it applies a force acting perpendicular to the tension force or the stretching force to the sheet. Thereby, the relevant sheet can be transversely straightened during stretching, such that the sheet is prevented from bending during stretching. Preferably, a plurality of movable transverse straightening presses are provided, and the transverse straightening presses can move together in the stretching direction of the sheet during stretching.

[0019] Alternatively or additionally, a centering device may be provided at at least one transverse straightening press, which centering device centers the sheet when the sheet is fed to the second chuck.

[0020] The object on which the present invention is based is also achieved by a method of stretching a metal semi-finished product in the form of a single sheet along a stretching section by means of the above-described sheet stretching machine according to the present invention. The method is characterized by the following method steps:

[0021] - Feeding the single sheet to a first chuck with its first narrow edge in the axial direction of the stretching section,

[0022] - Guiding the sheet through the first chuck and feeding the sheet to a second chuck with its first narrow edge in the axial direction of the stretching section,

[0023] - Fixing the sheet in the first chuck and the second chuck,

[0024] - Stretching the sheet to a preset length with a preset stroke, and

[0025] - Transporting the stretched sheet through the second chuck in the axial direction of the stretching section.

[0026] The sheet can be guided past the first chuck and fed to the second chuck and the stretched sheet can be transported through the second chuck by means of the first and second loading devices.

[0027] Advantageously, the sheet is transversely straightened by means of at least one transverse straightening press during stretching, i.e., transversely to the axial extension or transversely to the stretching force acting in the axial direction. During stretching, at least one transverse straightening press can move together in the stretching direction of the sheet.

[0028] Preferably, the sheet is automatically positioned at a preset position within the stretching frame by means of at least one position measuring system before being fixed in the chuck by means of the first and / or second loading devices. For example, a grating can be constructed in the chuck, which detects the position of the sheet. With the position information thus obtained, the drive of the loading device can accurately position the sheet within the stretching frame. Description of the Drawings

[0029] The present invention will be explained below with reference to the accompanying drawings according to embodiments.

[0030] The drawings show:

[0031] Figure 1 A side view of a sheet stretching machine according to the present invention is shown, and

[0032] Figure 2 Shows according to Figure 1 A top view of the sheet stretching machine. Detailed Description of the Invention

[0033] The sheet stretching machine 1 according to the present invention comprises a stretching frame 2, said stretching frame having first and second chucks 3, 4 which are movable within the stretching frame 2. The stretching frame 2 comprises first and second stretching cylinders 5, 6, wherein the first stretching cylinder is supported on a first pressure column 7 and the second stretching cylinder 6 is supported on a second pressure column 8. The first and second pressure columns 7, 8 respectively form supports for first and second stretching rods 9, 10 of the first and second stretching cylinders 5, 6. The first and second stretching rods 9, 10 are respectively arranged aligned with the first and second pressure columns 7, 8 and form the stretching frame 2. The first chuck can be displaced along the stretching rods 9, 10 by means of the stretching cylinders 5, 6. The stretching cylinders 5, 6 are loaded with a pressure medium by means of a hydraulic drive, whereby a movement of the first chuck 3 relative to the second chuck 4 in the axial direction of the stretching section formed by the stretching frame 2 is caused. In the described embodiment, the second chuck 4 is locked relative to the pressure columns 7, 8, i.e. fixed, while the first chuck 3 can move relative to the second chuck 4.

[0034] The chucks 3, 4 respectively have chuck mouths 11. The chuck mouths face away from each other within the stretching frame 2. The chuck mouth 11 of the first chuck 3 is open towards the input roller path 12 and the chuck mouth 11 of the second chuck 4 is open towards the output roller path 13. The chucks 3, 4 respectively comprise clamping jaws 16 which wedge the sheet along the stretching direction and which can be opened for threading of the sheet or semi-finished product. The input roller path 12 and the output roller path 13 comprise driven rollers.

[0035] A first loading device 14 is associated with the first chuck 3, said first loading device being arranged on the side facing the chuck mouth 11, while a second loading device 15 is associated with the second chuck 4, said second loading device being arranged on the side facing away from the chuck mouth 11. The loading devices 14, 15 comprise driven rollers and cause positioning and centering of the sheet within the stretching frame 2.

[0036] A sheet not shown is fed to the stretching frame 2 from the right via the input roller path 12 in the drawing. The sheet is then received by the first loading device 14 and guided centrally through the chuck mouth 11 of the first chuck 3 accordingly. The first narrow edge of the sheet (the narrow edge leading in the conveying direction) is fed to the second chuck 4 and introduced and fixed in said second chuck. The second narrow edge of the sheet (the narrow edge following in the conveying direction) is fixed in or is fixed in the first chuck 3. Then the first chuck 3 moves relative to the second chuck 4, wherein the sheet is stretched between the first and second chucks 3, 4. After the stretching process is completed, the clamping or wedging of the sheet is released and the sheet continues to be fed through the second chuck 4 onto the output roller path 13. Immediately afterwards, another sheet can be loaded via the input roller path 12.

[0037] List of reference numerals

[0038] 1 Sheet stretching machine

[0039] 2 Stretching frame

[0040] 3 First chuck

[0041] 4 Second chuck

[0042] 5 First stretching cylinder

[0043] 6 Second stretching cylinder

[0044] 7 First pressure column

[0045] 8 Second pressure column

[0046] 9 First stretching rod

[0047] 10 Second stretching rod

[0048] 11 Chuck mouth

[0049] 12 Input roller table

[0050] 13 Output roller table

[0051] 14 First loading device

[0052] 15 Second loading device

[0053] 16 Jaw

Claims

1. An apparatus for stretching a metal semi-finished product in the form of a single sheet along a stretching section having a stretching frame (2), the apparatus comprising: Pressure columns (7, 8) extending in the axial direction of the stretching section; A first chuck (3) in which the first narrow edge of the semi-finished product to be stretched can be clamped and the first chuck can be axially displaced by means of stretching cylinders (5, 6); and a second chuck (4) in which the second narrow edge of the semi-finished product to be stretched can be clamped, characterized in that at least one axial input device and an axial output device of the stretching frame (2) are provided, and the chucks (3, 4) are configured such that the semi-finished product to be stretched can be axially guided through at least one, preferably through two chucks (3, 4).

2. The device according to claim 1, characterized in that The axial input device includes an input roller table (12) and the axial output device includes an output roller table (13).

3. The device according to claim 2, wherein The input roller table (12) and / or the output roller table (13) includes driven rollers.

4. The device according to claim 2 or 3, characterized in that, The input roller table (12) and / or the output roller table (13) is height adjustable.

5. The device according to any one of claims 1 to 4, characterized in that, A first loading device and a second loading device (14, 15) are provided, wherein the first loading device (14) is associated with the first chuck (13) and the second loading device (15) is associated with the second chuck (4), wherein the loading devices (14, 15) preferably each include driven rollers.

6. The device according to claim 5, characterized in that The loading devices (15, 15) each have at least one centering unit.

7. The device according to any one of claims 1 to 6, characterized in that, At least one preferably movable transverse straightening press is provided between the first chuck and the second chuck (3, 4).

8. A method for stretching a metal semi-finished product in the form of a single sheet along a stretching section by means of the device according to any one of claims 1 to 7, characterized in that, The method has the following method steps: - Feeding a single sheet in the axial direction of the stretching section with its second narrow edge to the first chuck; - Guiding the sheet through the first chuck and feeding the second narrow edge of the sheet in the axial direction of the stretching section to the second chuck; - Fixing the sheet in the first chuck and the second chuck; - Stretching the sheet to a preset length with a preset stroke; and - Transporting the stretched sheet in the axial direction of the stretching section through the second chuck.

9. The method according to claim 8, characterized in that, Guiding the sheet through the first chuck and feeding the sheet with its second narrow edge to the second chuck, and transporting the stretched sheet through the second chuck by means of the first loading device and the second loading device.

10. The method according to claim 9, wherein Transversely straightening the sheet during stretching.

11. The method according to any one of claims 8 to 10, characterized in that, Moving at least one transverse straightening press in the stretching direction of the sheet during stretching.

12. The method according to any one of claims 8 to 11, characterized in that The sheet is automatically positioned in a preset position within the stretching frame by means of at least one position measuring system before being fixed in the chuck by means of the first loading device and / or the second loading device.

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