Perforating machine and method for producing a perforated material section

Abstract

The invention relates to a perforating machine (1) for producing a perforated material section (2), comprising: a tool upper part (11) which can be moved in a stroke direction H and which comprises a plurality of perforating needles (2) that are arranged in a specified pattern in a transverse direction Q and can be moved via a press beam (15) such that the perforating needles punch through the inserted material section (20); a stationary tool lower part (12), the material section (20) being supplied between the tool lower part and the tool upper part (11); and a hold-down device (13) which is arranged between the tool upper part (11) and the tool lower part (12) and which can be moved in the stroke direction H via the press beam (15) such that the hold-down device (13) presses together the inserted material section (20) against the tool lower part (12) to an adjustable height in order to punch the perforating needles (2) into the material section (20) to be perforated. The invention also relates to a method for producing a perforation (10) of a material section (20) using a perforating machine (1) according to one of the aforementioned claims, having the following steps: supplying the material section (20) between the tool lower part (12) and the hold-down device (13); pressing together the material section (20) to an adjustable height using the hold-down device (13); and producing a perforation (10) of the material section (20) by punching the material section (20) by means of the perforating needles (2).

Description

[0001] DESCRIPTION

[0002] Perforation machine and method for producing a perforated material section

[0003] The present invention relates to a perforation machine for producing a perforated material section and a method for producing a perforation of a material section with such a perforation machine.

[0004] The present invention is in the field of perforation machines, in particular perforation machines for perforating laminated materials.

[0005] DE 33 39 503 A1 discloses a punching machine with several punches, each interacting with a die, a drive device for the punch movements, and a feed device for the cyclical advancement of the material to be punched through the punching machine. At least one of the punches, preferably all of the punches, is provided with its own switchable drive and / or a switchable coupling to the drive device. The punching machine further comprises a machine table with several receiving positions, each for a tool unit. The tool unit has at least one die and at least one punch that can be actuated by the drive device.The tool unit with the die and a punch interacting with the die has its own switchable drive or a switchable and de-switchable coupling device for transmitting the punch drive force. DE 41 35 787 A1 describes a punching processing device for producing a punching pattern, comprising an upper die with a punch holder with several punches and with an underlying stripper plate with bores for receiving the ends of the punches projecting from the punch holder in such a way that they can be extended or retracted, and a lower die with bores into which the ends of the punches enter during the punching process. Feed devices move a material unit inserted between the lower die and the stripper plate intermittently synchronously with the punching process.The punches are held in the punch holder for upward and downward movement, with the top surfaces of the punch heads being either smooth or flush with the upper surface of the punch holder. Press heads are used, each with a head surface for depressing the punch heads. Additionally, a stepped portion preventing depressing is movable by press head drive devices such that either the head surface or the blunt portion is aligned with the respective punch head. The press head drive devices are controlled by a control circuit that generates binary-coded processing data corresponding to the punching pattern.

[0006] German utility model DE 20 2017 103 498 U1 discloses a perforating machine with a machine table and a striking element movable relative thereto. A perforating tool is mounted either on the machine table or on the striking element, and a die is associated with the other part of the perforating tool. The tool is guided between the perforating tool and the die in a driveable manner in the longitudinal direction of the material web for perforating the material web. Additionally, means are provided for simultaneously moving the perforating tool and the die in the transverse direction to the material web.

[0007] German utility model DE 20 2014 104 997 U1 describes a punching machine with several punching dies, whose punch heads are mounted in a punch support plate. The mounting of the punch heads in the punch support plate is designed in such a way that an undercut is created during the return stroke of the punches, with a drive element indirectly moving the punch support plate. The punching machine has at least one locking element, which is assigned to at least one punch and is located between the drive element and the punch support plate.The locking element is movable in two operating positions, wherein in a first operating position the locking element fills the space between the drive element and the punch head of the at least one punch and in a second operating position the locking element forms its free space above the punch head of the at least one punch and wherein in addition the at least one punch is held by a braking element at least in the second operating position of the locking element.

[0008] From the German utility model DE 20 2019 000 468 a punching / perforating machine is known which is equipped with the following features, namely a punching / perforating tool with a plurality of punching punches / perforating needles arranged in a longitudinal direction in a predetermined grid, which are movable via a pressure bar which is operatively connected via a control device to a drive unit for generating a punching / perforating stroke transversely to the longitudinal direction, a control block for controlling / activating / deactivating the punching punches / perforating needles by the control device during the punching / perforating process and is characterized in that the punching / perforating tool and / or the control block is / are each designed as a separate assembly, which is each arranged separately as a unit detachably attachable within the punching / perforating machine.With this punching / perforating machine, the material unit Z-web is fed intermittently in the transport direction before each punching / perforating stroke, and the punching or perforation is performed. The punching / perforating pins, which are individually activated for each stroke, can be individually activated or deactivated for the punching / perforating process. Due to the cyclical feeding of the material unit Z-web, the possible perforation patterns are predetermined by the design specifications of this machine.

[0009] Conventional perforation machines secure the piece of material to be perforated by enclosing it in a frame. When an elastic material is introduced into the punching / perforating machine, the material may deform, for example, if the punching die is pressed against the surface. This is particularly disadvantageous for multi-layered elastic materials, such as laminated leather. If the material is compressed differently during punching, variations in the perforation pattern can occur.

[0010] Based on the cited prior art, the present invention is based on the object or technical problem of providing a perforating machine of the type mentioned above that enables the precise perforation of elastic materials by compressing the material in the direction of movement of the perforating needles, thus reducing its height. The perforating machine according to the invention and the method for producing a perforation using such a perforating machine are defined by the features of independent claims 1 and 10, respectively. Advantageous embodiments are the subject of the respective dependent claims.

[0011] The invention comprises a perforation machine for producing a perforated material section, comprising an upper tool part, a lower tool part, and a hold-down device. The upper tool part is movable in a stroke direction and has a plurality of perforating needles arranged in a transverse direction in a predetermined grid, which are movable via a pressure bar such that they punch through the inserted material section. The lower tool part is stationary, with the material section being fed between the lower tool part and the upper tool part.The hold-down device arranged between the upper and lower tool parts is movable in the stroke direction via the pressure beam such that the hold-down device presses the inserted material section against the lower tool part to a variably adjustable height (in order to establish predetermined (at least two) different (vertical) positions of the hold-down device according to the material section) in order to punch the perforating needles into the material section to be perforated through the pressed material section. Variable means that the height adjustment, for example, pneumatically or mechanically, can be selected differently depending on the material section, so that the thickness in the pressed state of the material section can be changed, particularly depending on the material section.By the hold-down device pressing the inserted material section against the lower tool part to an adjustable height, it is possible to perforate elastic materials precisely because the material section is compressed to the same height each time before punching, which ensures uniform material processing. The perforating needles (punches) contained in the tool can be controlled independently of one another and can therefore be selected according to the desired perforation pattern. According to an advantageous aspect, first springs with a spring constant K1 are arranged between the lower tool part and the hold-down device, and second springs with a spring constant K2 are arranged between the hold-down device and the upper tool part, where K1 < K2. This means that less force is needed to compress the first springs than is required for the second springs.

[0012] Preferably, the spring constants K1 and K2 are selected such that, upon movement of the pressure beam toward the lower tool part, the hold-down device is pressed via the second springs against the force of the first springs to the adjustable height of the hold-down device. The second springs thus transfer the force exerted by the pressure beam on the upper tool part to the hold-down device, while the distance between the upper tool part and the hold-down device remains constant.

[0013] Advantageously, the difference between spring constants K1 and K2 is selected such that the first springs are compressed to the adjustable height until they reach the hold-down device, before the perforating needles punch into the material section, whereby the second springs are then compressed. If K1 is selected in this way, the first springs are compressed and the hold-down device is pressed against the material section, thus compressing it. Accordingly, K2 should also be selected such that more force is required to compress the second springs than to compress the material section. Only when the adjustable height is reached can the hold-down device no longer be pressed down, so that the second springs are compressed by the applied force.

[0014] According to a preferred aspect, the length of the second springs is selected such that when the second springs are compressed upon movement of the pressure beam, the perforated needles punch completely through the inserted material section and are inserted into the lower part of the tool. When the second springs are relaxed, the perforated needles are completely above or in the hold-down device, so that they do not touch the material section. Only when the second springs are compressed does the distance between the upper part of the tool, on which the perforated needles are arranged, and the hold-down device decrease, so that the needles are pushed through the hold-down device and penetrate the material section. The lower part of the tool has recesses coordinated with the position of the perforated needles, into which the perforated needles penetrate after completely penetrating the material section.

[0015] According to one advantage, the perforation machine further comprises column guides between the lower tool part and the blank holder. These maintain the precise position of the upper and lower tool parts relative to each other, thus ensuring precise and repeatable movement of the tool parts.

[0016] The height is preferably adjusted using an intermediate layer, whereby the intermediate layer is interchangeably arranged between the hold-down device and the lower tool section. The intermediate layer is attached to the hold-down device. Depending on the height of the intermediate layer, the movement of the hold-down device is limited by the intermediate length coming into contact with the lower tool section. This means that the height to which the material section is pressed can be varied by using different intermediate layers. This can prevent tool wear or breakage during the machining process. Furthermore, depending on the material type, thickness and strength, the optimal hold-down force can be used to securely fix the material without damaging it. This enables even pressure distribution during machining. It also prevents displacement of the material in the T / Q direction during the process.According to an advantageous aspect, the perforation machine further comprises a fitting screw, which adjusts the distance between the hold-down device and the lower tool part when the first springs are in the relaxed state. This allows the distance to be adjusted to the height of the material section to be inserted.

[0017] Advantageously, the inserted material section comprises multi-layer material with a flexible layer, with the adjustable height of the hold-down device being selected such that the flexible layer is compressed. Examples of multi-layer materials include leather, synthetic leather, paper, film including carrier materials such as foam, or laminated materials.

[0018] A further aspect of the invention comprises a method for creating a perforation in a material section using a perforation machine according to one of the preceding claims, comprising the steps of feeding the material section between the lower tool part and the hold-down device, compressing the material section to an adjustable height using the hold-down device, and creating a perforation in the material section by punching the material section using perforating needles. The compression and perforation of the material section occur sequentially due to the force exerted by the continuous movement of the pressure bar on the upper tool part.

[0019] Advantageously, the material section is pressed together before the perforating needles touch the material section for punching. This pressing action fixes and compresses the material section so that the perforation is created precisely across the entire height of the material section.

[0020] It is preferred that the perforating needles be withdrawn from the material section before the compression of the material section is released. This occurs by releasing the force from the pressure bar, and the second springs first relax. Subsequently, the decreasing pressure of the hold-down device leads to a relaxation of the material section. This is supported by the relaxation of the first springs.

[0021] The invention and advantageous embodiments thereof are described and explained in more detail below with reference to the examples shown in the drawings. The features shown in the description and the drawings can be used individually or in any combination according to the invention.

[0022] They show:

[0023] Fig. 1 schematic representation of a perforation machine according to the invention

[0024] Fig. 2 Cross section of the first spring

[0025] Fig. 3 Schematic representation of a material section with perforation

[0026] Fig. 1 shows a perforation machine 1 according to the invention for producing a perforated material section 20, wherein the transport direction T of the material section 20 points into the plane of the drawing. This perforation machine 1 comprises an upper tool part 11 movable in a stroke direction H with several perforating needles 2 arranged in a transverse direction Q in a predetermined grid, which are movable via a pressure bar 15, and a fixed lower tool part 12, between which and the upper tool part 11 the material section 20 is fed. Between the upper tool part 11 and the lower tool part 12, a hold-down device 13 is arranged, which is located above the

[0027] Material section 20 and is movable in the stroke direction H via the pressure beam 15 such that the hold-down device 13 presses the inserted material section 20 against the tool base 12 to an adjustable height in order to punch the perforating needles 2 into the material section 20 to be perforated through the pressed-together material section 20.

[0028] First springs 31 with a spring constant K1 are arranged between the lower tool part 12 and the hold-down device 13, and second springs 32 with a spring constant K2 are arranged between the hold-down device 13 and the upper tool part 11. The spring constant K1 is smaller than that of the second springs K2. In the variant of the perforation machine shown here, the first and second springs 31, 32 are compression springs. First and second springs 31, 32 are preferably located on both sides of the inserted material section 20. The spring constants K1 and K2 are selected such that the movement of the pressure beam 15 in the direction of the lower tool part 12 presses the hold-down device 13 against the force of the first springs 31 up to the adjustable height. The second springs 32 transfer the force of the pressure beam 15 to the hold-down device 13. The material section 20 is also pressed against the lower tool part 12 to a predetermined height.The difference between the spring constants K1 and K2 is also selected such that the first spring 31 is compressed until the hold-down device 13 has reached the set height. If the hold-down device 13 is still above the set height, the second spring 32 is only compressed to a negligible extent. Only when the hold-down device 13 is positioned are the second springs 32 then compressed, so that the perforating needles 2 penetrate into the material section 20. Due to the selected length of the second spring 32 and the perforating needles 2 and the selected height of the hold-down device 13, the perforating needles 2 penetrate completely through the inserted material section 20 when the second springs 32 are compressed. The tips of the perforating needles 2 can be inserted into the lower tool part 12. For this purpose, recesses can be arranged in the lower tool part 12, which are matched to the grid in which the perforating needles 2 are arranged on the upper tool part 11.

[0029] Once the material section 20 is penetrated by the perforated needles 2, the pressure bar 15 releases the force, causing the second springs 32 to relax and thus pull the perforated needles 2 out of the material section 20. Once they no longer completely touch the material section 20, the first springs 31 also relax, so that the hold-down device 13 is raised, so that the material section 20 is no longer compressed.

[0030] Column guides can be seen between the lower tool part 12 and the hold-down device 13. These ensure precise alignment of the two, which is also maintained during the movement of the hold-down device 13 relative to the lower tool part 12 in the Q and T directions. If the perforation needles 2 are guided through guiding recesses in the hold-down device 13, as in the example shown in Fig. 1, this ensures that the perforation 10 in the material section 20 is identical in each repetition. In addition, an intermediate layer 16 is arranged on the hold-down device 13 on the side facing the lower tool part 12. This intermediate layer is replaceable and determines the height to which the material section 20 is pressed together.

[0031] Fig. 2 shows the cross-section of a first spring 31 and its surroundings. It can be seen that the intermediate layer 16 has a recess for the first spring 31, so that its length and thus its restoring force are independent of the intermediate layer 16 used. It is shown that a fitting screw 17 is inserted into the first spring 31, with which the distance between the hold-down device 13 and the lower tool part 12 can be changed when the first springs 31 are in the relaxed state. This allows even taller material sections 20 to be fed into the perforation machine 1 after adjustment using the fitting screw 17.

[0032] Fig. 3 shows an example of an inserted material section 20. This is a multi-layer material 21, 22 with a flexible layer 22. The upper layer 21 can comprise a less elastic material such as leather or paper. The creation of a perforation 10 with a perforation machine 1 comprises the steps of feeding the material section 20 between the lower tool part 12 and the hold-down device 13, pressing the material section 20 together to an adjustable height by the hold-down device 13 and creating a perforation 10 in the material section 20 by punching the material section 20 using perforating needles 2. The figure shows that the perforation 10 comprises both the upper layer 21 and the flexible layer 22. The perforation 10 can, as shown, only partially extend into the flexible layer 22 or penetrate it completely.

Claims

CLAIMS 1. Perforation machine (1) for producing a perforated material section (2) comprising - a tool upper part (11) which is movable in a stroke direction (H) and has a plurality of perforating needles (2) arranged in a transverse direction (Q) in a predetermined grid, which perforating needles can be moved via a pressure bar (15) in such a way that they punch through the inserted material section (20); - a fixed tool lower part (12), between which and the tool upper part (11) the material section (20) is fed; and - a hold-down device (13) arranged between the upper tool part (11) and the lower tool part (12), which is movable in the stroke direction (H) via the pressure bar (15) such that the hold-down device (13) presses the inserted material section (20) against the lower tool part (12) to a variably adjustable height in order to punch the perforating needles (2) into the material section (20) to be perforated through the pressed-together material section (20).

2. Perforation machine (1) according to claim 1, wherein first springs (31) with a spring constant K1 are arranged between the lower tool part (12) and the hold-down device (13), and second springs (32) with a spring constant K2 are arranged between the hold-down device (13) and the upper tool part (11), wherein K1 <K2.

3. Perforation machine (1) according to claim 1 or 2, wherein the spring constants K1 and K2 are selected such that by a movement of the pressure beam (15) in the direction of the tool lower part (12) the hold-down device (13) is pressed via the second springs (32) against the force of the first springs (31) up to the adjustable height.

4. Perforation machine (1) according to claim 2 or 3, wherein the difference between the spring constants K1 and K2 is selected such that the first springs (31) are compressed to the adjustable height until they reach the hold-down device (13) before the perforating needles (2) punch into the material section (20), whereby the second springs (32) are compressed.

5. Perforation machine (1) according to one of the preceding claims, wherein the length of the second springs (32) is selected such that when the second springs (32) are compressed after reaching the hold-down device (13) to the adjustable height upon movement of the pressure bar (15), the perforating needles (2) punch completely through the inserted material section (20) and are introduced into the lower tool part (12).

6. Perforation machine (1) according to one of the preceding claims, further comprising column guides (40) between the tool lower part (12) and the hold-down device (13).

7. Perforation machine (1) according to one of the preceding claims, wherein the height is adjusted via an intermediate layer (16), wherein the intermediate layer (16) is arranged interchangeably between the hold-down device (13) and the lower tool part (12).

8. Perforation machine (1) according to one of the preceding claims, further comprising a fitting screw (17), with which the distance between the hold-down device (13) and the lower tool part (12) is adjusted in the relaxed state of the first springs (31).

9. Perforation machine (1) according to one of the preceding claims, wherein the inserted material section (20) comprises multi-layer material (21, 22) with a flexible layer (22), and wherein the adjustable height is selected such that the flexible layer (22) is compressed.

10. A method for producing a perforation (10) of a material section (20) with a perforation machine (1) according to one of the preceding claims, comprising the following steps: - feeding the material section (20) between the tool base (12) and the hold-down device (13); - compressing the material section (20) to an adjustable height by the hold-down device (13); and - Creating a perforation (10) of the material section (20) by punching the material section (20) using perforated needles (2).

11. The method according to claim 10, wherein the material section (20) is compressed before the perforating needles (2) (20) touch for punching.

12. The method according to claim 10 or 11, wherein the perforating needles (2) are pulled out of the material section (20) before the pressing of the material section (20) is released.

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