CH717313A2 - Device for removing a punched part from a punching device. - Google Patents

Abstract

The invention relates to a device for removing a punched-out part (13) from a punching device (10), the parts being punched from an endless web of a film and discharged through an output opening in the die, the punched-out part (13) being introduced through an introduction opening in a magazine (15) arrives. The invention is characterized in that the device has at least one holding part with an outer surface (7), that the outer surface (7) has at least one suction area which is operatively connected to a negative pressure source (vacuum source), that the holding part along a path can be moved from the dispensing opening to the introduction opening, in the area of which the punched-out part (13), preferably by a stripping surface (16), is stripped from the holding part and fed to the introduction opening.

Description

The invention relates to a device for removing punched parts from a punching device, according to the preamble of claim 1.

The punching device, to which the invention relates in particular, punches out of continuous material that is present in film form, parts, so-called circuit boards, which are used to close yogurt cups, coffee capsules and other containers. The thickness of the endless web is less than 0.5 mm, mostly far less. The foils are mainly structured as follows: Aluminum in combination with a sealing medium, sealing media can be heat seal lacquers or sealable coex coatings; Polyester (PET) in one or more layers with a seal coating; Combinations of paper with plastic, for example PET / paper / PET; Paper (especially in the case of film webs containing paper, the maximum thickness can be achieved) with at least one barrier layer; compostable plastics such as PLA; also in the above-mentioned combinations with plastics; laminated aluminum foils, possibly laminated with plastic film (s) or paper, Aluminum / aluminum composites are also conceivable, also multi-layer V, with 2-layer composite one speaks of duplex, with 3-layer of triplex composite film.

All of these films can be printed, both in mirror and in frontal printing.

In the prior art, the punched part, the board, is pressed by the punch into a through opening, the punch opening, the die and forms in this a growing stack consisting of the punched parts. On the outside of the die, where the through opening forms an output opening, a magazine is attached with an inner shape that corresponds to the circumferential shape of the punched parts, and in which a movable, variously spring-loaded or otherwise guided stop is provided, if necessary. The bottom of the stack of punched-out parts rests against the stop; and it is either moved by the punching force, or it is moved accordingly from the outside. If a sufficiently high (thick) stack has been formed in this magazine, depending on the experience of the user, punched parts in the appropriate height, thus estimated number, are removed by hand, the stamp is brought back into the adjacent position and if necessary all of this takes place either without or with only a brief interruption in the punching process.

For the punching process itself should only be carried out that usually several, offset in the direction of movement, rows with parts to be punched are provided from the clocked moving endless material in order to utilize the endless material as much as possible. The pressure already applied, etc., is taken into account, all of this is known in the prior art and therefore does not require any further explanation here.

The main disadvantage of this known from the prior art procedure is that the number of each manually removed parts can never be precisely determined, and that it is therefore necessary for the producer to work with a certain margin of safety in order to raise objections avoid, and that this will result in a significant loss of profitability. Another set of problems concerns the necessary manual handling of the removed stack itself, because despite the use of gloves and breathing masks, in rare cases, but inevitably, individual parts are contaminated, which is disadvantageous in subsequent use, practically exclusively in connection with food is. Any kind of late removal of a sufficiently grown stack either leads to an emergency stop of the punching device as a whole or, even worse, to overflowing of the stack or to problems with the punching itself when the stack "grows back" into the punching form, the foil deformed or damaged and thus also interferes with the punching of the other webs.

There is thus a great need for a device which avoids these disadvantages and it is the aim and object of the invention to provide such a device.

The object of the invention is achieved by a device which has the features specified in the characterizing part of claim 1. In other words, a device is attached to the outside of the punch in the area of the dispensing opening which moves a holding part with an outer surface past the dispensing opening, the outer surface having at least one area which is in operative connection with a negative pressure source (vacuum source) stands (suction area), whereby a board located in the dispensing opening is sucked in and placed against it, and wherein the outer surface together with the adjacent board is moved from the dispensing opening to a dispensing area, where the board, preferably through a stripping surface, is moved from the outer surface is stripped off and gets into a magazine.

The term negative pressure source means in the application and the claims that it has the effect that an air pressure below ambient pressure always prevails on the at least one area of the outer surface during the operative connection.

These features can be realized essentially by two types of devices: In the first variant, the device has at least one arm which is rotatably mounted with a shaft about its, preferably horizontal, axis and at its free end either itself, or in the form of an attached plastic part having the outer surface, which is in communication with the vacuum source through the arm and the shaft.

When using a plastic part, the arm has an end face which is preferably approximately tangential to the axis and is either flat or cylindrical, with generators approximately parallel to the axis of rotation of the arm.

In a variant, the arms can be designed to be radially divided, the outer part being designed to be pivotable within limits with respect to the inner part, whereby the peripheral speed of the suction area can be well controlled.

In the second variant, the outer surface is formed on a plate or plate-shaped part, which is moved in a guide, for example by means of a toothed belt, past the dispensing opening and is guided to the dispensing area. There, after the board has been dispensed, the small plate is moved back to the dispensing opening, with an intermediate storage facility possibly being arranged in order to be able to easily and quickly exchange one type of plate for another type of plate.

The generally preferred clocking of the movement can be achieved by appropriate transfer of the platelets to different transport devices in the individual sections of their trajectory, which has the advantage that only individual platelets have to be delayed and accelerated again. A certain disadvantage is the not so simple supply of vacuum, but this can be done by the individual transport devices where it is necessary along the path of movement, and otherwise be dispensed with without disadvantages.

More about the first embodiment:

If the arm is now, preferably clocked, with the standstill or strong slowdown, then occurs when the end face is in the area of the dispensing opening, is rotated about its axis, so the frontmost board (the punched piece) remains according to the The negative pressure depends on the outer surface and is guided by the further rotation to the delivery area, in which it is stripped from the surface and, due to the circumferential speed, slides approximately tangentially, preferably along a guide surface, into the magazine.

The timing of the arm movement can, but does not have to be, matched to the timing of the punching device. For example, a slightly higher number of cycles can be provided in order to make it easier and possible to have a time reservoir for changing the magazine when the arm is stationary, without having to stop the punching device.

Under clocked is understood that the rotation of the shaft is always briefly stopped or at least almost stopped when the arm is with its outer surface essentially in the middle (in the area of the centroid) to the punched part, so that the suction and adhesion can take place without a (disruptive) sliding movement occurring. As a result, the relative position between the punched-out part and the surface of the arm is determined with sufficient accuracy, and is maintained even when the punched-out part is accelerated and transported.

Since it comes to punching rates with a cycle of up to 500 / min, you can not get by with just one arm on the shaft, and in one embodiment of the invention it is therefore provided that several arms are arranged evenly distributed around the shaft , are provided, of course, are always located in the same plane normal to the shaft.

Excellent results were achieved with six-armed devices in which the offset in the circumferential direction was 60 °, which caused the shaft and arms to stop six times per revolution, something that is not a problem with stepper motors or the like even at the necessary speeds .

For reasons of strength and because of the ease of processing, the production by turning, milling, wire erosion, etc. from an aluminum disc is the preferred production method, whereby aluminum (or aluminum alloy) due to its low density also the necessary acceleration and stopping compared to stainless steel or others Materials favors. The use of plastic is possible, but only makes sense in special cases because of the more complex production compared to aluminum.

For better adhesion of the punched parts and to reliably prevent their unwanted contact with aluminum, as is often required, the actual contact surface (= surface of the arm) is optionally made of a layer of food-grade plastic (silicone, NBR, PUR ), which is clamped, screwed or otherwise fastened onto the aluminum part of the arm, whereby either a distribution of the suction channels can also be provided in the plastic part, or channels that are essentially radially aligned with the openings provided for this purpose in the aluminum part are provided . Instead of individual clamping parts on the respective arm, it is also possible to form a ring, possibly with a suitably structured inner surface, complementary to the end faces.

The invention is explained in more detail below using an exemplary embodiment of the first embodiment and with reference to the accompanying drawings. 1 shows an axial view of a first embodiment according to the invention, partially in section, FIG. 2 shows a section along the line II-II in FIG. 1, FIG. 3 shows a view in the direction of the arrow III of FIG. 1, FIG. 4 a perspective view, FIG. 5 a side view of the entire device, partly in section, FIG. 6 an embodiment of the first variant on a punch, partly in section and FIG. 7 the second embodiment.

DieFig.1 shows a view in the axial direction of a shaft on which a removal wheel 1 with six arms 2 is mounted. An opening 3 can be seen in the center, which is used to attach it to the shaft (not shown). The six arms 2 are connected to one another by a stabilizing ring 4 in order to increase the mechanical stability and to prevent vibrations. At the outer end, the arms 2 have heads 5 which are used to attach plastic supports 8, which in turn come into contact with the punched parts to be removed. In the embodiment shown, approximately U-shaped plastic parts (support 8) are placed over the central areas of the heads 5 and fixed in the U-shaped recesses of the respective head 5 by frictional engagement by means of elastically deformable clamping strips 9. This has proven to be easy to replace and therefore easy to clean after it has been removed.

In partial section, a longitudinal bore 6 can be seen in the interior of one of the arms 2, which extends from the central opening 3 to the end face 11 of the arm, below (within) the support 8 made of plastic.

DieFig.2 shows a section along the line II-II of Fig. 1, the longitudinal bores 6 as well as the thin supports 8 and the central opening 3 are clearly visible.

DieFig.3, a view in the direction of the arrow III in FIG. 1, shows the outer surfaces 7 of the supports 8, which are provided with several suction openings 12. which become channels through the inner surface of the supports 8, which lead to the individual suction openings 12 and, in total, form the suction area 19 to which a vacuum (negative pressure), possibly also overpressure, is applied.

DieFig.4 represents an embodiment of the invention in a perspective view, the arms 2, the ring 4, the suction openings 12 and the clamping strips 9 can be clearly seen.

DieFig.5 shows, schematically and partially in section, the arrangement of a removal wheel 1 on a punching device 10, of which only the area in which the punched parts, the boards 13, a stack 14 in the through opening of the die 21 to Form output opening is shown. For the sake of simplicity, the punching plane is shown oriented vertically, but in practice it is mostly inclined “backwards” so that the punching tool performs a downward movement with one component in the working direction.

The moment of contact of one of the outer surfaces 7 with the foremost board of the stack 14 is shown, without loss of generality, with the horizontal arm 2 and the vertical position of the boards in the stack 14. The direction of rotation of the wheel 1 is indicated by the arrow D. indicated, for the sake of clarity, no circuit board is shown on the neighboring arm; only again on the arm, which is close to the area of a magazine 15, is one drawn in. This board protrudes several times over the width of the outer surface 7 on both sides of the plane of the drawing and is moved by a sliding surface 16 provided on both sides of the outer surface 7, which can be part of the magazine or, preferably, is fixedly arranged on the removal device detached from the outer surface 7 and, through its impulse, reaches the magazine 15 along the sliding surface 16, where the stack 20 that has already been formed is indicated by corresponding hatching. The clear dimensions of the magazine correspond at least essentially to those of the output opening of the punching device. In practice, the longitudinal extension of the magazine 15 is usually significantly longer in order to be able to accommodate a larger number of blanks 13.

The clocking of the movement of the wheel 1 facilitates the precise counting of the blanks removed and, when the desired number of pieces is reached, stops the removal and thus enables the magazine to be changed. After changing the magazine, blanks are removed again at a greater speed than are punched, the stack 14 becomes more “airy” and the game repeats itself.

The situation in the area of removal from the stack can be varied in different ways and adapted to the circumstances. Thus, a retaining device for the blanks is preferably provided at the end of the punching device in the area of the dispensing opening, which allows the arm to pass through in a suitable (radial) size and thus ensures that removal conditions are always the same. In addition, when the wheel is at a standstill (removal of the magazine), the arm 2, which is then directed towards the stack 14, can also support the latter, namely in the central area of its end face.

An embodiment of this embodiment is shown in FIG. 6, which shows a situation similar to that of FIG has in the embodiment on the stabilization ring 4 joints 23 for the arms 2 with axes of rotation parallel to the axis of rotation 17, so that their inner sections, from the shaft with the opening 3 to the ring 4, do not move relative to one another, but their outer sections 22 around the respective axis are pivotable.

The joints 23 preferably also have the transition openings for the discharge of air to the shaft, these can be interrupted under certain circumstances in suitable positions to facilitate the detachment of the boards and to prevent the suction of air when empty. If this is not desired, flexible hoses can be arranged in cross bores to ensure the connection.

This pivoting is effected by a lever 24 which is fixedly, in particular non-rotatably, connected to the outer section 22, which is guided with its free end in a link 26 by means of a sliding block or a roller 25. In a manner known per se, the local angular speed (and thus the local circumferential speed) of the suction area 19 is determined by the interaction of the link, lever joint and outer section and can be adapted to the respective specifications. In particular, on the one hand a complete stopping of the removal wheel 1 as a whole can be avoided, while at the same time the suction area nevertheless comes to a complete or almost complete standstill in the removal area.

With knowledge of the invention, the person skilled in the art can easily determine the necessary shape of the backdrop. The stabilizing ring 4 does not have to be provided if it also allows the joints 23 to be designed in a simple and stable manner.

The Fig. FIG. 7 shows an example of the second embodiment of the invention in a representation analogous to that of FIG. The belt 27 runs over a guide 28, which is curved in the example shown, and two deflection rollers 29, 30 with the running direction in the direction of the arrow L. Preferably, the roller 30, which is arranged at the end of the guide 28, is driven so that the belt 27 is in the area the guide 28 (upper run) is reliably subjected to train and therefore rests on the guide 28. A regulation of the tension of the belt 27 can be created either by a movable, preloaded bearing of the roller 29 or a separate tensioning device. As an alternative to the driven roller, a drive via a friction roller or a toothed belt (with a toothed belt) can be provided in the lower strand.

In the area of the guide 28, the application of a vacuum between the guide and the back of the belt and suitable openings in the belt in the area of the suction areas 19 ensure that they are supplied with negative pressure. In the area of the delivery point, for the roll 30, the supply can be minimized, for example by the lack of connections to the vacuum source or even the provision of ventilation openings, and thus the delivery can be made easier; A subdivision transverse to the direction of movement is also possible, which allows overpressure to be applied in the delivery area. The sliding surface of the guide is, because of the necessary supply of negative pressure, at least in the area that is swept over by the openings in the band, correspondingly profiled in order to allow the passage of the sucked air; The supply openings in the guide must also be provided in this area.

Since, as mentioned at the outset, the parts 13 to be punched are usually provided in several lanes on the endless belt, several, mutually offset removal devices are to be arranged in the punching device 10, which is easily accomplished by a person skilled in the art with knowledge of the invention.

A wide variety of sensors can be provided for monitoring which, for example, optically recognize the unwanted detachment of circuit boards during transport with the arm and ensure a suitable response via an IT system.

The possibility created by the device according to the invention of arranging one or more sensors for checking the quality of the board in the area of its trajectory is particularly favorable. These sensors can optically check the print image including its conformity with the outline of the punched-out part, they can check the uniformity of the thickness of the sealing layer and the like. The fact that they are connected to a corresponding evaluation unit and trigger the intended reaction when anomalies are detected then again corresponds to the state of the art and does not need to be explained in more detail here.

Geometrically, it should be noted that the total radius from the axis of rotation 17 to the end face 11 or, if available, to the outer surface 7 of a support 8 corresponds to the distance of the axis of rotation to the output opening of the die, the tolerance of the strength (thickness) of a few punched-out parts 13 corresponds. With regard to this “output opening of the die, it should also be noted that it does not have to be aligned with an outer surface of the punching device, but can be at a distance from it, for example by means of guides, as shown in FIG. 6. It is preferred that, as shown in FIG. 5, the arm 2 comes into a position that is parallel, preferably in alignment, with the axis of the stack (leading through its center of gravity). Then, when the wheel 1 comes to a standstill, a safe suction of the foremost plate at the appropriate point is guaranteed.

To avoid sucking in dust or foreign bodies, it is possible to make the connection of the longitudinal bores 6 with the central opening or the vacuum line there so that a connection with the vacuum source takes place only in the angular position in which it is for suction and keeping a circuit board is necessary. This can also reduce the power of the vacuum source. In further refinements, it is possible to subdivide the opening 3 and to apply excess pressure to the arms 2 in the angular positions in which they do not transport a blank in order to reliably blow any dirt out of the various bores, openings and lines.

In the description and the claims, the terms “front”, “rear”, “top”, “bottom” and so on are used in their usual form and with reference to the object in its usual position of use. When it comes to an endless belt, “running direction” refers to the local direction of movement in the intended operation, “transverse to it” essentially means a direction that is rotated by 90 °.

It should also be pointed out that in the description and the claims information such as "lower area" of a suspension, reactor, filter, structure, or a device or, more generally, an object, the lower half and in particular the lower Quarter of the total height means, "lowest area" the lowest quarter and in particular an even smaller part; while "middle area" means the middle third of the total height (width - length). All of this information has its common meaning, applied to the intended position of the object in question.

In the description and the claims, “essentially” means that a deviation of up to 10% of the specified value, if it is physically possible, includes both downwards and upwards, otherwise only in the meaningful direction is. When specifying degrees (angle and temperature), this means ± 10 °.

In terms such as: "a solvent", a suction area, etc., the word "a" is not to be regarded as a numerical word, but as an indefinite article or as a pronoun, unless the context indicates otherwise.

The term: “combination” or “combinations”, unless otherwise stated, stands for all types of combinations, starting from two of the constituents in question up to a large number or all of such constituents, the term: “containing” also stands for "consisting of".

The features and variants specified in the individual configurations and examples can be freely combined with those of the other examples and configurations and used in particular to characterize the invention in the claims without necessarily taking along the other details of the respective configuration or the respective example

List of reference symbols:

1 removal wheel 2 arms 3 opening 4 stabilization ring 5 heads 6 longitudinal bore 7 outer surface 8 plastic support 9 clamping strip 10 punching device 11 end face 12 suction opening 13 blanks 14 stack (through opening) 15 magazine 16 sliding surface 17 axis of rotation 18 through opening 19 suction area 20 stack (magazine) 21 Die 22 outer section 23 Joint 24 Lever 25 Guide roller 26 Link 27 Belt 28 Guide 29 Deflection roller 30 Deflection roller 31 Punching tool

Claims (7)

1. Device for removing a punched-out part (13) from a punching device (10), the parts being punched from an endless web of a film and discharged through an output opening in the die (21), the punched-out part (13) being fed through an introduction opening reaches a magazine (15), characterized in that the device has at least one holding part with an outer surface (7), that the outer surface (7) has at least one suction area (19) which is in operative connection with a negative pressure source (vacuum source) means that the holding part can be moved along a path from the dispensing opening to the introduction opening, in the area of which the punched-out part (13) is stripped from the holding part, preferably by a stripping surface (16), and fed to the introduction opening. 2. Device according to claim 1, characterized in that the punched-out part (13) is stripped off by applying excess pressure to the suction area (19). 3. Device according to claim 1 or 2, characterized in that it has at least one arm (2) which is rotatably mounted with a shaft about its, preferably horizontally arranged, axis of rotation (17) that the arm (2) at its free End, its head (5), which forms the holding part, has an end face (11) that at least one opening in this end face is connected to the vacuum source through the arm (2) and the shaft, and that the end face (11 ) the outer surface (7), or this is formed on a support (8) on the head (5). 4. Apparatus according to claim 3, characterized in that the arms (2) are divided into inner sections, which are immovable with respect to the shaft, and outer sections (22) which are connected to the inner sections via joints (23), and that the outer sections (22) are non-rotatably connected to levers (24), the free ends of which are guided by means of guide rollers (25) which run in a link (26). 5. The device according to claim 4, characterized in that it has several arms (2), that these are connected to one another by means of a stabilizing ring (4), and that the joints (23) are arranged in the connection area. 6. Apparatus according to claim 1 or 2, characterized in that the suction areas (19) of the outer surface are arranged on an endless belt (27) and are connected by means of through openings to the underside of the belt, that the belt (27) from the The dispensing opening is moved to the introduction opening and is guided in this area by a preferably curved guide (28) so that the vacuum source is in operative connection with the volume between the guide (28) and the belt (27), that in the area of the dispensing opening and the introduction opening deflection rollers ( 29, 30) are provided for the band (27). 7. Apparatus according to claim 6, characterized in that the deflection roller (30) provided in the region of the introduction opening drives the belt.