DE20216108U1 - Punch, embossing and forming machine for flat material, has press part connected to punch tool via pivotally mounted lever - Google Patents

Abstract

The press part (3) acting upon the punch tool (11) is connected to a lever (5) pivotally mounted in the machine frame. This lever is connected to the punch tool via a roller (7.1) and intermediate lever (7), so that when the press part is in the resting position, the punch tool is raised, and the press part can be moved quickly in a downwards direction without encountering any force in order for it to reach a position immediately above the flat material, subsequent movement of the press part being through the deadpoint region at a very shallow angle, in order to generate a high press or punch pressure over a short path. Once punching, embossing or forming is complete, the press part is returned to its starting position, since the kinetic energy after the deadpoint region acts in the upwards direction. The machine is used to punch, emboss and/or form flat pieces or webs of paper, plastic, laminated paper, metal or similar material.

Description

Utility model registration:

(10.10.02/gr1)

1. Applicant:

Grossmann Maschinenbau GmbH, Donauschwabenstr. 27, 89555 Steinheim

2. Title:

Punching and/or embossing device for high cycle rates

3. Area of application:

Punching holes and/or embossing in a continuous process in flat semi-finished products, such as plates, strips, cut pieces made of the following materials: cardboard, laminated cardboard material, multilayer material, sheet metal, etc.

4. Preliminary remarks on the state of the art :

If you want to punch holes in flat materials economically and with the highest precision in a continuous process or make similarly economical and precise impressions in such materials, it is important to carry out an equally short punching process with a small stroke in the very short downtimes using a process that enables very short cycle times.

According to the current state of the art, the following work is carried out:

5. State of the art and disadvantages of the state of the art:

The state of the art known to the inventor provides for a direct hydraulic or pneumatic drive of the punching tool.

The full punching force must be applied in the punching direction, which leads to jerky or shock-like force progression and only allows low cycle speeds, since the retraction of the cylinder acts as a loss of time.

Other solutions also work with a pneumatic cylinder as a drive and integrated linear guide, which, in addition to the disadvantages described above in mass production, also has the disadvantage of a shorter service life (malfunctions sometimes occur after just 40 hours). For these reasons, previous punching tools are considered to be a brake on the machines.

Solutions with a rotating punching tool, the axis of which is parallel to the strip but transverse to the direction of travel, and which allow punching without stopping the strip, require that the rotation speed of the punching tool and the strip speed are absolutely synchronized during the punching process. Such solutions are currently only known in designs in which the precision of punching required for many applications is not achieved, with problems both in maintaining the exact position coordinates of a hole and in the diameter or profile tolerances and the tolerances for right-angled cutting from top to bottom, i.e. concerning the hole wall.

6. Object of the invention:

The object of the invention is to implement a large number of very short, high-precision punching strokes in succession for creating punch holes or embossings (recessed, raised or mixed) during the short downtimes of otherwise rapidly moving flat material.

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• t t

The control can be set up in such a way that, for safety reasons, the cylinder only receives an impulse when the track is at a standstill.

To become even faster, it can also be controlled so that the punching tool moves in the direction of the moving material web, but only touches the material web when the relative speed between the punching tool and the material web is zero.

Solution to the task:

The task is solved by the pressing force acting either through a pneumatic cylinder on a kinematic system (knee lever principle, cam discs or the like) so that both the forward stroke and the reverse stroke lead to a punching process, whereby the punching tool is first guided close to the strip, which has been brought to a standstill for a short time, with a large and fast stroke and low force and then the embossing or punching is carried out with a short path and high force,
or a cam disk with an integrated cam groove ensures the movement sequence through a rotary motor (servo motor or similar), whereby at least 1, possibly even 2 to 4 punching strokes can be generated with one revolution.

or by a rotary motor (servo motor or similar), a punching tool carrier whose axis is parallel to the belt and perpendicular to the direction of travel is rotated, whereby a kinematic system of levers and/or cam disks keeps the actual punching tool absolutely parallel to the belt over the entire cutting depth during cutting and retraction, as is the analogously constructed counter tool under the belt, while the oval shape of the tool carrier means that after lifting off the moving belt, the rotation speed can be set by controlling the drive motor (servo motor) in such a way that the punching tool only comes into engagement again when the correct distance from hole to hole has been covered by the belt movement.

Advantages of the invention:

1. Flat, gentle, gliding, non-jerky force progression

Avoiding the impacts that occur when the full punching force is applied in a linear direction

2. Greatest force effect near the dead center

= long travel of the pneumatic cylinder and short travel of the punching tool.

3. Longer service life because only one forward or reverse stroke is required per punch.

4. Higher cycle speed, since the pneumatic cylinder uses forward and reverse strokes or the servo motor can convert one revolution into one or more punching cycles.

5. High precision in terms of the accuracy of the position coordinates, the hole profile and hole wall tolerances.

9. Description of implementation examples:

Examples of implementation are shown as sketches and are described in more detail below.

Show it:

Figure 1 shows a simple embodiment of the invention. A cylinder pivot bearing 2 and a pneumatic cylinder 3 are attached to a base body 0 of the punching device with a holder for cylinder pivot bearing 1 (part of the base body) in such a way that the fork head 4 of the cylinder piston is connected to the upper toggle lever bearing 5.1 via a long lever 5, with the long lever 5 being moved about the toggle lever pivot point 5.2 in the base body recess 6 in such a way that on the other side the short lever 7 is moved in the opposite direction via the toggle lever joint 5.3, which is connected via the lower toggle lever bearing 7.1 to the holder for the lower toggle lever bearing 8, part of the base plate 9 for the punching die and the holder of the punching die 10 for the punching die 11. Since the holder for the lower toggle lever bearing 8 can only move in the direction specified by the column guides 12, the rotary movement on the short lever 7 causes a longitudinal movement in the punching direction, which initially occurs quickly and without counterpressure. As soon as the punching tool comes into contact with the strip, the toggle lever joint 5.3 is in the dead center area, ie the movement of the lever 5 only causes a small stroke in the punching direction, but with very great force due to the small angle shortly before the dead center.

Figure 2 shows the position of the long lever 5 and the short lever 7 for the lowest position of the punching tool 11, in which the punched material can fall freely downwards.

Figure 3 shows the position of the toggle lever connection 4, 5, 7, 8 when the piston of the pneumatic cylinder 3 has been fully extended and the punching tool 11 has been retracted.

When the pneumatic piston is retracted, the same punching process takes place, i.e. two punching processes are achieved with a back and forth movement of the piston of the pneumatic cylinder 3.

Figure 4 shows an embodiment in which the toggle lever connection 4, 5, 7, 8 is replaced by a curve segment 5, which lies in a recess 6 provided for this purpose in the base body 0 and is moved about the curve segment pivot point 5.2, whereby by means of curve 7 - a milling cutout forms an upper curve and a lower or complementary curve in which the rollers 7.2.1 and 7.2.2 rotate about the lower axle bolt 7.1, the holder 8 for the lower axle bolt 7.1 and thus the base plate 9 for the punch and the holder 10 of the punch 11 can be moved up and down in the direction of the column guide 12.

Here too, the downward movement initially occurs quickly and without counterpressure in accordance with the curve. As soon as the punching tool comes into contact with the strip, the transferring axle bolt 7.1 is in the dead center area, i.e. the movement of the cam disk 5 only causes a small stroke in the punching direction, but with great force due to the small angle before the dead center.

Figure 5 shows, analogously to Figure 2, the position of the curve segment 5, which has led the punching tool 8 to the bottom dead center. In a secondary figure (detail section through curve

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disc 5) shows how the rollers 7.2.1 and 7.2.2 are arranged in a milled recess of the curve segment 5 so that play-free guidance is ensured at the top and bottom and the movement can be transmitted downwards via axle bolt 7.1.

Figure 6 shows, analogously to Figure 3, how the base plate for the punch 9 was guided upwards again by fully extending the pneumatic piston 3.
When the cylinder 3 is moved back, the same punching process takes place, ie two punching processes can be carried out with one back and forth stroke.

Figure 7 shows an embodiment in which a servo motor 3 acts as a pressure sensor via a cylinder 5 with milled curves 7 on rollers 7.2.1 and 7.2.2 that run in the curves and thus move the holder 8, the base plate 9, the holder 10 with the punch 11 downwards or upwards depending on the curve.

The curve is chosen in such a way that the punching knife is moved very quickly towards the strip through a steep curve and then the curve becomes increasingly flatter, similar to an oblique plane, so that a great deal of force can be exerted on the material over a short punching path.

Figure 8 shows a similar design in which the servo motor is replaced by a rack and pinion, which is acted upon by a hydraulic or pneumatic pressure sensor. All other functions are analogous to those in Figure 7.

Figure 9 shows that a pressure sensor 3 acts on a cam rod 5 which is mounted in such a way that it moves in the longitudinal direction, whereby the cams 7 milled on both sides act on the punching knife 11 via rollers 7.2.1 and 7.2.2 via the holder 8, the base plate 9 and the tool holder 10. Here too, the curve is selected in such a way that when the tool is started up, the tool is quickly brought to the material strip by means of a steep curve and then a very large force can be exerted on the punching knife by means of a flatter curve at the turning point of the curve.

Figure 10 shows that the rotary encoder 3 moves the rotary lever 5 in a circular motion via the axis 4 when the tool holders 10 fastened to the rotary lever 5 come close to the material strip, and are held absolutely parallel to the strip in the punching area via bolts 12.1 and 12.2 which engage in curves which are introduced on the respective opposite side of the base frame.

As soon as the tool holders 10 with tool 11 have been lifted out of the belt area, they leave the curves and can then be moved upwards without guidance.

The same applies to the counterpart with lower tool 11.1 mounted on the underside.

The rotary lever 5 can be designed for 1, 2, 3 or more tools.

Claims (7)

1. Device for punching, embossing and/or deforming flat elements or webs made of paper, plastic, laminated paper, metal or similar material with a pressure sensor which acts on a punching tool, characterized in that the pressure sensor 3 is connected to a lever 5 which is also mounted on the base frame and which is connected to the associated punching tool via rollers 7.1 in Fig. 4 or intermediate lever 7 in such a way that when the pressure sensor is in the rest position the punching tool is raised, when the pressure sensor moves the punching tool quickly without pressure build-up. B. moves downwards into the punching position close to the material to be processed and the further movement of the pressure sensor through the dead center area runs at a very flat angle (inclined plane/curve), whereby a high punching or pressing pressure can be generated over a short distance, while after punching, embossing or processing has been completed, the further movement of the pressure sensor brings the tool back again, since the kinematics after the dead center area causes a longitudinal movement in the opposite direction, i.e. upwards. 2. Device according to claim 1 ( Fig. 1 to 3/4 to 6), characterized in that the axis of the punching tool runs preferably at a right angle to the axis of movement of the pressure sensor operating with forward and backward movement. 3. Device according to claim 1 ( Fig. 7 and 8), characterized in that the axis of the punching tool running in the direction of movement is identical to the axis of the pressure sensor operating with rotary movement, or runs parallel thereto. 4. Device according to claim 3 ( Fig. 7), characterized in that the pressure sensor is a servo motor 3, which is connected via a cylinder 5 with milled curves 7 and rollers 7.2.1 and 7.2.2 via holder 8, base plate 9, holder 10 to the punch 11 in such a way that the punch is moved up and down when the cylinder 5 rotates. 5. Device according to claims 3 and 4 ( Fig. 8), characterized in that instead of the servo motor as a pressure sensor, a hydraulic or pneumatic piston 3 is connected to the cam cylinder 5 via a rack 4.1 and a pinion 4.2. 6. Device according to claim 1 and 2 ( Fig. 9), characterized in that the pressure sensor 3 acts on a curved rod 5 with curves 7 on both sides, in which rollers 7.2.1 and 7.2.2 are located on both sides, which are connected to the punching tool 11 via holder 8 with base plate 9 and tool holder 10, so that a reciprocating longitudinal movement leads to up and down movement of the punching tool. 7. Device according to claim 1 ( Fig. 10), characterized in that the axis of the punching tool holder is arranged at right angles to the axis of a pressure sensor working with rotary movement and can thus rotate about the axis of the pressure sensor, the punching tool is movably attached to the punching tool holder and is kinematically guided via levers and/or cam disks in the immersion or punching area absolutely parallel to the material strip and the distance to the strip to be processed is reduced by slightly more than the punching stroke, so that when the punching tool holder is rotated after the punching knife has touched the strip, the punching knife and strip move at the same speed as a roller with a counter tool arranged underneath in the same direction.