Press for producing a molded part and method for changing a die on a press

Abstract

In order to shorten set-up times, a press for producing a molded part from pourable material, having an apparatus for driving a die comprising a cylinder unit having a cylinder housing and having a cylinder piston is proposed, wherein the cylinder housing is the actuator of the cylinder unit and the cylinder piston is the stator of the cylinder unit.

Claims

1. Press for production of a molded part from a pourable material, having an interchangeable adapter that comprises a pressing unit for accommodating a die, and having an apparatus for driving the die, comprising a cylinder unit having a cylinder housing and a cylinder piston, wherein the pressing unit has an upper traverse and a lower traverse that are held at a distance from one another via columns, on which a die accommodation plate of the pressing unit is displaceably mounted, wherein the cylinder housing is an actuator of the cylinder unit and the cylinder piston is a stator of the cylinder unit, and the cylinder piston comprises a ring piston that is fixed in place with reference to the cylinder unit.

2. Press according to claim 1, wherein the cylinder housing is disposed on an outside of the stator of the cylinder unit, displaceable relative to the cylinder unit.

3. Press according to claim 1, wherein the cylinder housing is disposed to be fixed in place on a die accommodation of the die.

4. Press according to claim 1, further comprising indexing or positioning bolts for guiding the interchangeable adapter with regard to a machine table of the pressing unit.

Description

(1) Further advantages, goals, and properties of the present invention will be explained using the following description of a powder press for the production of a molded part from a pourable material, which is particularly shown also in the attached drawing. The drawing shows:

(2) FIG. 1A schematically, a side view of the press, partly in section, with an interchangeable adapter that has not yet been lowered, in a pressing position;

(3) FIG. 1B schematically, a side view of the press, partly in section, with an interchangeable adapter in a set-up position, before it is moved into the pressing position shown in FIG. 1A;

(4) FIG. 2 schematically, in a further side view, partly in section, of the press from FIGS. 1A and 1B, with the interchangeable adapter partly lowered; and

(5) FIG. 3 schematically, a further side view, partly in section, of the press from FIGS. 1A, 1B, and 2, with the interchangeable adapter completely lowered.

(6) A first exemplary embodiment, shown in FIGS. 1 to 3, shows a press 1 for the production of a molded part from a pourable material, having an interchangeable adapter 2 comprising a pressing unit 3 having a die accommodation plate 4 for accommodating a die, not shown here.

(7) The pressing unit 3 has an upper traverse 5 and a lower traverse 6, which are held at a distance from one another by means of columns 7 (numbered only as an example here). In this exemplary embodiment, the columns 7 are configured as slide devices 8 on which the die accommodation plate 4, in particular, can slide and thereby be displaced in height within the pressing unit 3. In this exemplary embodiment, the pressing unit 3 comprises a total of four columns 7.

(8) To drive the die accommodation plate 4, the pressing unit 3 comprises a corresponding apparatus 9 for driving the die, not shown here, or the die accommodation plate 4, which apparatus comprises a cylinder unit 10 having a two-part cylinder housing 11 and having a cylinder piston 12. It is unusual, in this connection, that the cylinder housing 11 is the actuator of the cylinder unit 10 and the cylinder piston 12 is the stator of the cylinder unit 10; in other words, the cylinder housing 11 is the moving part of the cylinder unit 10 and the cylinder piston 12 is the fixed component with regard to the cylinder unit 10.

(9) This means that the cylinder housing 11 is displaced with regard to the cylinder piston 12, thereby making it possible to achieve the enormous advantage that pourable material that is lying around can reach sensitive regions of the cylinder unit 10 in significantly poorer manner, ideally not at all. As a result, the risk of increased wear, for example on sealing devices of a hydraulic system of the cylinder unit 10, is reduced, thereby making it possible to advantageously reduce the maintenance effort and the maintenance frequency.

(10) This also makes significantly faster and more cost-advantageous changing of the die on the press 1 possible, among other things, because the adapter 2 can be replaced significantly faster than was usual until now, as a result of the low maintenance effort.

(11) It is understood that the stator can be implemented in many varied structures. It has proven to be particularly advantageous to configure the cylinder piston as a ring piston 13 that is fixed in place with regard to the cylinder unit 10, as is implemented in the present exemplary embodiment.

(12) In contrast, the cylinder housing 11 is disposed on the outside—shown with the reference number 14—on the stator of the cylinder unit 10, in displaceable manner, preferably in translationally 15 displaceable manner, with regard to the cylinder unit 10.

(13) In this connection, the cylinder housing 11 is firmly connected with the die accommodation plate 4.

(14) Both the stator and the actuator of the cylinder unit 10 are disposed concentrically around the center press axis 16 of the press, in this exemplary embodiment, thereby creating a very stable cylinder unit 10.

(15) According to a further aspect of the present invention, the press 1 is characterized by a vertical drive 20 for the interchangeable adapter 2. The vertical drive 20 comprises a device 21 for raising and/or lowering the interchangeable adapter 2, whereby the raising and/or lowering device 21 is disposed, in this exemplary embodiment, in its essential modules, on the underside—indicated with the reference number 22—of the interchangeable adapter 2.

(16) The raising and/or lowering device 21 is equipped with one hydraulic adapter clamping cylinder 23 and four hydraulic track cylinders 24 (numbered as examples here). Both the adapter clamping cylinder 23 and the track cylinders 24 are provided in a floor plate 25 of the press 1. In this connection, the adapter clamping cylinder 23 is disposed centrally, and the track cylinders 24 are disposed in corner regions of the foundation 25, in each instance.

(17) The adapter clamping cylinder 23 has a clamping head 26 at the top, which can engage into a corresponding undercut 27 of the lower traverse 6, when the interchangeable adapter 2 is moved or has been moved into a pressing position 28. Such a pressing position 28 is shown in FIGS. 1A, 2, and 3.

(18) The floor plate 25, together with the counter-sinkable track rails 29, forms a machine table 30 of the press 1. The counter-sinkable track rails 29 and the hydraulic track cylinders 24 are components of a height level regulation (not explicitly numbered here) of the vertical drive 20 and are essentially oriented parallel to the hydraulic adapter clamping cylinder 23. In this regard, the main directions of action of the hydraulic track cylinders 24 can be oriented counter to the main direction of action of the hydraulic adapter clamping cylinder 23, in structurally simple manner, thereby making it possible to always press the adapter 2 against the counter-sinkable track rails 29 and to thereby hold the interchangeable adapter 2 in firm contact with the counter-sinkable track rails 29 with its chassis 31.

(19) In this exemplary embodiment, the chassis 31 comprises wheels 32 (numbered only as examples here).

(20) It is understood, however, that the chassis 31 can also have a different form, for example can be equipped with a corresponding pneumatic system, thereby allowing the interchangeable adapter 2 to slide over the track 34 between a set-up position 33 (see FIG. 1B) and the pressing position 28.

(21) Good vertical guidance of the interchangeable adapter 2 occurs, in the pressing position 28, also by means of a vertical support 35 of the vertical drive 20, as will be described further below.

(22) For advantageous movement of the interchangeable adapter 2 between the pressing position 28 and the set-up position 33, the interchangeable adapter 2 has a horizontal drive 40 having a mobile change-over cart 41. The interchangeable adapter 2 can thereby be displaced, in advantageous manner, by means of a simple horizontal translational movement between the pressing position 28 and the set-up position 33.

(23) For horizontal guidance of the interchangeable adapter 2, the horizontal drive 40 also comprises a horizontal stop 42, which particularly serves as a move-in limit for the change-over cart 41. In this way, horizontal pre-positioning of the interchangeable adapter 2 can be guaranteed in particularly rapid and operationally reliable manner.

(24) The present press 1 can have a particularly simple construction in that the horizontal stop 42 simultaneously carries the vertical support 35 for the interchangeable adapter 2. If necessary, the horizontal stop 42 can have a sensor system for detection of the position and/or speed of the change-over cart 41 on its side facing the interchangeable adapter 2. Such a sensor system can, however, also be provided at another suitable location, also on the change-over cart 41 or the interchangeable adapter 2. In particular, it is also possible that one part of this sensor system is provided on the horizontal stop 42 or at a different suitable fixed location, while another part is provided on the change-over cart 41 or on the adapter 2, and both of these parts of the sensor system interact with one another.

(25) The press 1 is particularly also developed further by means of an automatic change mechanism, which works together with the sensors mentioned above for automatic displacement of the interchangeable adapter 2 into a working region, in this exemplary embodiment the pressing position 28 of the press 1, or out of the working region of the press 1.

(26) To control the speed of the mobile change-over cart 41 of the interchangeable adapter 2, the automatic change system advantageously possesses a device for controlling the speed. In this regard, the risk of damaging the press 1 or the interchangeable adapter 2 as the result of an unsuitable speed is almost completely excluded, because the change-over cart 41 can then gently drive up to the horizontal stop 42.

(27) With regard to a further aspect of the present invention, the press 1 has a hydraulic coupling 50 with an adapter-side coupling part 51 and with a press-side coupling part 52.

(28) Furthermore, the hydraulic coupling 50 has a device 53 for coupling the two coupling parts 51 and 52, whereby the coupling device 53 has not only fixed coupling elements 54 but also movable coupling elements 55.

(29) The interchangeable adapter 2 can additionally support itself vertically with the adapter-side coupling part 51, for which purpose the adapter-side coupling part 51 is laid down onto the press-side coupling part 52. Centering of the interchangeable adapter 2 in the region of the hydraulic coupling 50 takes place by means of the fixed coupling elements 54. Once the interchangeable adapter 2 has been pre-centered within the press in such a manner, the hydraulic coupling 50 can additionally be coupled by means of the movable coupling elements 55, whereby the movable coupling elements 55 at least comprise an automatic coupling 56 (numbered only in FIG. 1B, for the sake of clarity).

(30) The press-side coupling part 52 is configured with a particularly simple construction by means of the vertical support 35 of the vertical drive 20, whereby the fixed coupling elements 54, as centering pins (not additionally numbered, for the sake of clarity), engage into corresponding bores of the fixed vertical support 35. In this regard, unintentional intrinsic tension of the adapter 2 within the press 1, as the result of which the hydraulic coupling could be subject to overly great stress, is excluded.

(31) Furthermore, in this exemplary embodiment the hydraulic coupling 50 also comprises at least the hydraulic adapter clamping cylinder 23 for vertical displacement of the interchangeable adapter 2 with regard to the machine table 30, so that the adapter-side coupling part 51 and the press-side coupling part 52 can be coupled with one another during lowering of the interchangeable adapter 2. In this regard, in this exemplary embodiment, the hydraulic coupling 50 is also characterized, in its totality, by the hydraulic adapter clamping cylinder 23.

(32) The press 1 furthermore has indexing or positioning bolts 57 for guiding the interchangeable adapter 2 directly on the machine table 30, which bolts can be assigned, in this exemplary embodiment, additionally to the coupling elements 54 and 55 of the coupling device 53 of the hydraulic coupling 50. In this way, the interchangeable adapter 2 can be pre-positioned within the press 1, on the machine table 30, even before the coupling elements 54 and 55 of the coupling device 53 engage between the adapter-side coupling part 51 and press-side coupling part 52, and this can accordingly be advantageous even independent of the hydraulic coupling 50, but, in interplay with the hydraulic coupling 50, particularly protects the other fixed coupling elements 54, such as the centering pins, from overload, so that these can regularly be designed to be more delicate and therefore less robust.

(33) The essential course of the method for changing a die on the press 1 is structured as follows in this exemplary embodiment:

(34) The interchangeable adapter 2 is transferred from the pressing position 28 (see FIG. 1A) to the set-up position 33 (see FIG. 1B). There, either the die can be removed from the die accommodation plate 4 and replaced with a different die, so that subsequently the interchangeable adapter 2 is moved back from the set-up position 33 to the pressing position 28. Or the entire adapter 2 is replaced with a different interchangeable adapter 2, which was previously equipped with a corresponding die. In any case, the adapter 2, correspondingly prepared with the required die, is transferred from the set-up position 33 back to the pressing position 28. In this connection, the interchangeable adapter 2 is rolled, with its wheels 32, over the track 34, onto the counter-sinkable track rail 29, which surrounds the machine table 30 of the pressing unit 3 at least in part. Up to that time, a first interstice 70 with a distance that is selected to be sufficiently large so that the indexing and positioning bolts 57 are situated above the track 34 or above the machine table 30 and that the movement sequences described above can proceed in operationally safe manner exists between the track 34 and/or the counter-sinkable track rail 29 and/or the foundation 25. The distance of the first interstice 70 is determined, in fixed manner, by the selected diameter of the wheels 32, in this exemplary embodiment.

(35) Once the interchangeable adapter 2 has been brought up all the way to the horizontal stop 42 by means of its horizontal drive 40 (see FIG. 1A), the interchangeable adapter 2 is lowered within the press 1, along the center press axis 16, in a first lowering phase (see FIG. 2), by means of the counter-sinkable track rail 29. In this connection, the interchangeable adapter 2 is pre-positioned with regard to the machine table 30, by means of a vertical movement 71 (see FIGS. 2 and 3), in that the indexing and positioning bolts 57 thread into corresponding recesses 72 in the foundation 25.

(36) During the further course of the vertical movement 71, the interchangeable adapter 2 is additionally centered on the vertical support 35 by way of the hydraulic coupling 50, and also hydraulically coupled by means of closing the coupling 50.

(37) The vertical movement 71 is continued until the first interstice 70 (FIGS. 1A and 1B) successively decreases in size (see further interstice 73; FIG. 2), so that ultimately, the interchangeable adapter 2 sits on the floor plate 25 of the press 1 with its lower traverse 6, ready for use, and is clamped on the machine table 30 by means of the hydraulic adapter clamping cylinder 23 (FIG. 3).

(38) The vertical movement 71 downward and upward is essentially initiated by the adapter clamping cylinder 23.

(39) In order to be able to displace the die into an operating position, by means of the die accommodation plate 4, without the risk of excessive contamination by a pourable material existing in this connection, the cylinder housing 11 of the hydraulic cylinder unit 10 is displaced, in the sense of an actuator, with regard to the cylinder piston 12 of the hydraulic cylinder unit 10, thereby causing the die or the die accommodation plate 4 to be driven directly by the cylinder housing 11.

(40) It is understood that the exemplary embodiment explained above is only a first embodiment of the present invention. In this regard, the embodiment of the invention is not restricted to this exemplary embodiment that has been explained.

REFERENCE SYMBOL LIST

(41) 1 press 2 interchangeable adapter 3 pressing unit 4 die accommodation plate 5 upper traverse 6 lower traverse 7 columns 8 slide device 9 drive apparatus 10 cylinder unit 11 cylinder housing 12 cylinder piston 13 ring piston 14 outside 15 translational(ly) 16 center press axis 20 vertical drive 21 raising and/or lowering device 22 underside 23 adapter clamping cylinder 24 track cylinder 25 floor plate 26 clamping head 27 undercut 28 pressing position 29 track rail 30 machine table 31 chassis 32 wheels 33 set-up position 34 track 35 vertical support 40 horizontal drive 41 change-over cart 42 horizontal stop 50 hydraulic coupling 51 adapter-side coupling part 52 press-side coupling part 53 device for coupling 54 locally fixed coupling elements 55 movable coupling elements 56 automatic coupling 57 indexing and positioning bolt 70 first interstice 71 vertical movement 72 recesses 73 further interstice