EP1638711B1 - Embossing machine and method for embossing workpieces - Google Patents

Abstract

The embossing machine comprises a displaceably guided matrix frame (8) inside of which an eccentric shaft (4) for driving the die (13) is mounted. The matrix frame (8) is displaced by means of a cam plate (5) directly coupled to the eccentric shaft (4). This enables a forced movement between the die (13) and the matrix (9), which is superimposed with regard to the workpiece (1) to be embossed in such a manner that the die (13) executes only the smallest movements relative to the workpiece (1). The workpiece holder (15) is mounted in a manner that enables it to move relative the matrix frame (8), whereby the workpiece (1) is correctly positioned between the die (13) and the matrix (9) by a combined pivotal and displacing movement, and the embossing processes can be subsequently carried out on the periphery by rotating the workpiece holder (15). The forced guiding and the arrangement of the workpiece holder (15) make it possible to achieve very high working speeds with a high level of precision.

Description

The present invention relates to an embossing machine according to the preamble of claim 1, a method for embossing workpieces according to the preamble of claim 7 and the use of such embossing machine.

Embossing machines have long been known in various designs. The main tool of these machines is a punch, which is brought against the usually resting on a die or against it adjacent workpiece by applying pressure to a defined depth in abutment. The embossing achieves a plastic deformation of the material on the frosted area of the workpiece. As a rule, a recess is created on the side of the punch and, if necessary, a bulge is created on the side of the die.

As workpieces primarily metals are processed with such machines, which requires that the applied with the punch forces must be very large in order to achieve plastic deformation of the material.

The forces applied for this purpose are conventionally transmitted either mechanically via an eccentric shaft or hydraulically directly to the punch. The conventional mechanical machines usually have very large dimensions, since the force must be built and transmitted directly at the location of the stamp, and are therefore suitable for the processing of large items. The hydraulic machines can, since the pressure build-up separated from Stamp is made, also be smaller and are also suitable for the machining of smaller parts.

From the EP 1 074 320 is a mechanical punching and embossing machine is known in which by a forced coupling of the movement of the die and stamp with very small relative movements between the punch resp. Die and workpiece a punching or embossing effect is achieved.

This machine is particularly well suited for relatively small hollow cylindrical workpieces, in which the punches resp. Embossments along a single, defined radius must be rotationally symmetrical.

If, however, in the case of rotationally symmetrical, plate-shaped workpieces, in particular with concave or convex surfaces, the embossments must be carried out at different positions on the workpiece, then the machine has disadvantages due to its fixed workholding which can only be rotated about one axis. Thus, the workpiece must be repeated several times in several such machines for the different punching resp. Embossing positions are each set up and used separately. This means a disadvantageous cost and high production times.

The use of hydraulic machines is also not suitable due to the associated high manufacturing tolerances for such workpieces. The marking holding time required to achieve a precise embossing depth depends on various parameters whose precise compliance can not be guaranteed.

The object of the present invention was to find an embossing machine, which allows accurate, fast embossing in particular of rotationally symmetrical workpieces, wherein the embossments at different radial positions with mutually different wall inclinations resp. Curvatures must be performed.

This object is achieved according to the invention by a machine having the features of claim 1. Further, preferred embodiments of the machine result from the features of claims 2 to 6.

The fact that the workpiece holder is movable on the one hand in a plane relative to the machine frame, and on the other hand is pivotable about an axis perpendicular to this plane, the workpiece can be quickly and easily brought into the appropriate processing position. The machining of the imprints to be applied generally along the circumference of the workpiece at defined intervals can preferably be accomplished simply by arranging the retaining mandrel of the workpiece rotatably in the workpiece holder.

Preferably, this rotary drive, which is advantageously provided with a control for exact positioning, housed directly in the workpiece holder. In addition to the retaining pin, a counter-holder is preferably mounted in the workpiece holder, which is designed to be rotatable. This ensures a reliable and rotationally fixed fixation of the workpiece in the workpiece holder. At the same time, however, the workpiece can also be easily applied to the workpiece holder resp. remove from this again.

In order to make particular imprinted with respect to the circumferential line on the workpiece embossed, a sensor is preferably used. This sensor, preferably an optical sensor, is advantageously arranged directly on the workpiece holder and detects the position of the embossments already carried out. Based on this information, it is possible by means of a correspondingly established control, which controls the rotation of the retaining mandrel, simple and precise, to pivot the workpiece into the correct position for the following stamping operation.

This can be easily, quickly and in particular precise embossing executed especially on plate-shaped workpieces. Such workpieces are, for example, converter plates for use in automatic transmissions, such as those used in large numbers in vehicles. On the one hand, these are relatively small workpieces, in which the embossments must be carried out with high precision, since these serve to receive the guide vanes.

Preferably, the embossing machine according to the invention has a feed resp. Removal device for the workpieces, which automatically feeds the workpieces to the workpiece holder resp. this removed after processing.

In order to be able to carry out different embossings on the same workpiece as efficiently and quickly as possible, it is further preferably proposed that a plurality of processing stations be arranged parallel to one another. A processing station essentially has the punch and associated die and in each case an associated workpiece holder on. The transport from one processing station to the next can be done for example by the feeding and removal device. Thus, it is advantageously possible to achieve high production rates even with workpieces with mehren, different embossing forms, which must be produced with different punches and dies.

The object is further achieved by a method according to the features of claim 7. Further preferred embodiments emerge from the features of the further claims 8 and 9.

By preferentially detecting the already existing embossings, further embossings with different punches or on another circumferential line can be carried out with high precision and fast.

The combination of very precise and efficient mechanical stamping together with a flexible and precisely controlled workpiece fixture results in the desired high production rates with high accuracy.

According to the invention, such a machine according to claim 10 is used.

By the inventive arrangement resp. Sliding and pivoting of the workpiece holder embossments can be performed exactly and with high speed and precision at the designated positions on each workpiece.

• Fig. 1 den schematischen Längsschnitt durch eine erfindungsgemässe Maschine mit einem tellerförmigen Werkstück, welches mit dem Stempel von der Innenseite her bearbeitet wird;
• Fig. 2 den schematischen Längsschnitt im Bereich von Stempel und Matrize mit eingeführtem Werkstück; und
• Fig. 3 den schematischen Längsschnitt im Bereich des Werkstückhalters bei der Beschickung mit dem Werkstück.

An embodiment of the present invention will be explained below with reference to drawings. Show it

• 1 shows the schematic longitudinal section through an inventive machine with a plate-shaped workpiece, which is processed with the stamp from the inside;
• FIG. 2 shows the schematic longitudinal section in the area of punch and die with inserted workpiece; FIG. and
• Fig. 3 shows the schematic longitudinal section in the region of the workpiece holder in the loading of the workpiece.

FIG. 1 schematically shows the longitudinal section through an embossing machine according to the invention. The workpiece 1 to be machined is held in a workpiece holder 15, which is connected to the machine frame 16. In this case, the workpiece 1 is held rotatable about its axis of symmetry w.

About a drive shaft 3, for example, designed as a propeller shaft, the eccentric shaft 4 is driven. In the illustrated embodiment, the eccentric shaft 4 is arranged coaxially with the control disk 5.

The control disk 5 has on its underside a control track in the form of a circumferential groove 6. The groove 6 may be formed, for example, as eccentric to the axis of rotation of the eccentric shaft formed, circumferential groove. In this groove 6 engages a pin 7, which is connected to the feed carriage 2.

The delivery of the feed carriage 2, for example, via a threaded spindle 18 of a mechanical or electric drive 19 which is connected to the machine frame 16th is firmly connected to be set in the direction of the axis h to the workpiece 1. This setting is preferably NC controlled.

The eccentric shaft 4 is mounted in the die frame 8, which is guided in parallel in the direction of the machining axis h slidably in the machine frame 16. When driving the drive shaft 3, the die frame 8 is now according to the formation of the groove 6 of the control disk 5 periodically moved in his leadership back and forth, bringing the arranged at the end of Matrizenrahmens 8 die 9 against the corresponding outer side of the workpiece 1 comes into abutment. is lifted from it. According to the formation of the groove 6, this movement takes place with a larger or smaller path, in each case once per revolution.

At the eccentric pin 17 of the eccentric shaft 4, a connecting rod 10 is arranged, which is connected for example via a connecting pin 11 with the punch arm 12. This punch arm 12 is likewise arranged displaceably in the die frame 8 in the radial direction with respect to the workpiece axis w. During the rotation of the eccentric shaft 4 so that the punch arm 12 is once again reciprocated at each revolution and thus also the arranged at the end of the punch arm punch 13th

Due to the illustrated arrangement of the eccentric shaft 4, control disk 5 and eccentric pin 17, a coupled, positively driven movement of both the die 9 and the punch 13 is effected, wherein the relative movement of the punch 13 with respect to the workpiece 1 depending on the design and arrangement of the groove. 6 the control disk 5 in relation to the stroke of the eccentric pin 17 may be very small.

The workpiece holder 15 is now according to the invention designed such that therein the workpiece 1 is held rotatable about both the axis of symmetry w, but can also perform a vertical movement along the axis v and in addition a pivoting movement about the axis s, which is perpendicular to the axis h and v , can perform. Next punch 13 and die 9 can be moved along the axis h resp. be positioned. Thus, it is possible to position the workpiece 1 at the intended position for attaching embossing between the punch 13 and the die 9. These movements are advantageously NC controlled. Subsequently, the intended embossing can be carried out by defined defined rotational movements about the axis w with high precision along the circumference of the workpiece 1.

In particular dish-shaped, at the edge of a concave or convex surface having workpieces 1 can be processed by this machine very precise and fast.

If further embossments with the same embossing tool 13 along a further circumferential line on the workpiece 1 must be performed, this can be achieved by appropriate repositioning of the workpiece holder 15 and thus of the workpiece 1 with respect to punch 13, respectively. Matrix 9 is very easy and fast.

By detecting the already executed imprints, for example by means of an optical sensor, the starting position of the workpiece 1 can be easily determined and adjusted. This means that non-contiguous imprints in a defined position can be created quickly with high precision. This is required, for example, for components of automatic transmissions, such as Transducer plates, in which subsequently guide vanes must be used in these embossings. Very high demands are made on the precision of the embossing itself as well as their positioning on the workpiece 1.

If a plurality of embossments with different configurations, ie with different stamp shapes, have to be carried out on the same workpiece 1, a device is provided in which several, for example two or three such embossing stations are arranged and operated parallel to one another and the workpieces 1 are completely finished Processing on one of these stations the next station to be supplied. Thus, the workpieces 1 can be processed practically parallel and a very high production rate can be achieved.

FIG. 2 shows, in a smaller detail, the processing area of the embossing machine according to the invention in more detail. In the illustrated position, the workpiece 1 is already brought by the process and pivoting of the workpiece holder 15 in the desired processing position. The point to be machined of the workpiece 1 is exactly in the processing axis h of the embossing machine, ie between the punch 13 and the die 9. The interaction of the movements of the punch 13 and die 9 in a known manner, the embossing process can now be triggered, the position of the workpiece 1 remains unchanged. As a rule, several embossments along the circumference of the workpiece 1 at regular, defined intervals must be attached, this can be easily by rotating the workpiece 1 to the workpiece axis resp. Haltedornachse w done. So that the workpiece 1 is not in this position from the retaining pin 20th drops, a counter-holder 21 is provided, which reliably and the workpiece 1 against unintentional rotation pressed against the retaining mandrel 20. The counter-holder 21 is advantageously arranged axially movable on the workpiece holder 15 in order to release the workpiece 1 again.

Further, from Figure 2, the insertion of the workpiece 1 in this processing position augrund the starting position of the workpiece 1 'shown in dashed lines can be seen. In this position, the workpiece 1 is compared to the machining axis h in a vertical position, and can be introduced from top to bottom between the punch 13 'and die (not shown here). Subsequently, the workpiece 1 can be brought by combined lowering and pivoting in the position shown in Figure 2, i. the position of the axis of rotation s' shifts to position s. At the same time also punch 13 and die 9 are moved together to their original position. Through these common, coordinated movements virtually every position of the workpiece can be brought into a processing position between the punch 13 and die 9.

Finally, FIG. 3 also shows the charging or charging situation. The workpiece holder 15 is pivoted such that the workpiece 1 comes to lie upwards. From a feed device 22, the workpiece 1 is lowered down until it reaches the holding mandrel 20 in support. Subsequently, the counter-holder 21 can be positioned over the workpiece 1 and press this from above against the retaining mandrel. Now the workpiece holder 15 can be moved according to the previous description, ie be moved and swiveled, the workpiece 1 is held reliably.

The removal of the machined workpiece 1 can now be carried out in the same way in the reverse order.

Claims (10)

1. Embossing machine comprising machine frame (16), punch (13), female die (9) and a workpiece holder (15) for receiving a workpiece (1), wherein the female die (9) is held in a parallel in relation to the working axis (h) displaceably guided female die frame (8), which is relocatably guided within the machine frame (16) by a cam disk (5) in relation to the workpiece holder (15), and punch (13), which is arranged at a die arm (12) which is relocatably guided within the female die frame (8), is connected to an excentric shaft (4), which is rotatably mounted in the female die frame (8) of female die (9), and wherein the excentric shaft (4) and the cam disk (5) are directly coupled to one another and connected to a drive shaft (3), characterized in that the workpiece holder (15) is movably arranged within a guiding axis (v) perpendicular in relation to the working axis (h) and perpendicular in relation to the moving layer of the female die frame (8) and is rotatably arranged around a further rotating axis (s) arranged perpendicular in relation to the guiding axis (v) and perpendicular in relation to the working axis (h).
2. Embossing machine according to claim 1, characterized in that the workpiece holder (15) comprises a mandrel (20) and a slidable counter holder (21) for the workpiece (1), wherein said mandrel (20) is arranged perpendicular in relation to the rotating axis (s).
3. Embossing machine according to claim 2, characterized in that mandrel (20) is drivably arranged so as to be drivable via a driving facility, preferably around its positioning axis (w).
4. Embossing machine according to one of claims 1 to 3, characterized in that the workpiece holder (15) comprises at least one sensor for the detection of recesses or markings of the workpiece (1), preferably an optical sensor.
5. Embossing machine according to one of claims 1 to 4, characterized in comprising further a feeding installation, for applying or removing workpieces (1) to or from the workpiece holder (15).
6. Embossing machine according to one of claims 1 to 5, characterized in that multiple punches (13) and female die plates (9) are arranged parallel to each other within the machine frame (16) as discrete machining stations, each having its own workpiece holder (15).
7. Method for applying embossings to axial-symmetrical, dish-shaped workpieces (1) along at least one circumference line with an embossing machine according to one of claims 1 to 6, characterized in
   supplying the workpiece (1) to a workpiece holder (15) and holding said workpiece (1) centered;
   feeding the workpiece holder (15) in a linear motion in relation to the embossing machine and deviating it around a rotating axis (s) perpendicular in relation to the working axis (h) such as the circumference line for receiving an embossing will be positioned between the punch (13) and female die (9) of the embossing machine;
   whereas punch (13) and female die (9) will be eventually displaced in coordination along the working axis (h);
   subsequently performing embossing actions onto the workpiece (1) by the punch (13) and female die (9), whereas the workpiece (1) will be rotated about a predetermined angle around its axis (w) between two subsequent embossing actions;
   subsequently the workpiece holder (15) eventually being rotated around its rotating axis (s) into a further position, whereas eventually again the workpiece holder (15) is displaced along the working axis (h) in relation to the embossing machine and/or punch (13) and female die (9) and performing further embossing actions onto the workpiece (1);
   finally rotating the workpiece holder (15) around its rotating axis (s) into its initial position and eventually displacing it in relation to the embossing machine and thereafter detaching the processed workpiece (1) from the workpiece holder (15).
8. Method according to claim 7, characterized in that the workpiece (1) will be fed subsequently into at least two machining stations of the embossing machine arranged parallel to each other and will be machined therein.
9. Method according to claim 7 or 8, characterized in that preliminary to the start of the following machining action the position of an already machined embossing will be detected by a sensor, preferably by an optical sensor, and based upon the analysis of this detection the workpiece (1) will be rotated by the workpiece holder (15) around its axis (w) to establish a defined relative position of the already machined embossing in relation to the punch (13), either in the actual machining station or in the following machining station.
10. Use of an embossing machine according to one of the claims 1 to 6 for the machining of axial-symmetrical hollow-cylindrical workpieces (1), preferably with concave or convex surface.

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