Patent Application
20230372990
Extrusion presses usually operate in such a manner that a block to be extruded is pressed by a punch in the direction of a die (direct extrusion presses). In addition, extrusion presses with which a block transducer or transducer, as the case may be, with a metal block is pressed against a hollow pressing punch (indirect extrusion presses) are also common. Such presses comprise, for example, a press frame with one or more piston-cylinder units acting between a cylinder bar and a counter bar and applying the press force, along with a container holder and a running bar carrying a pressing punch. The runner bar and the container holder can be slid on guide columns of the press frame. In addition, these are provided with adjustable guide shoes, which have guide surfaces aligned with the main axis of the press. For trouble-free operation of such an extrusion press and for high dimensional accuracy of the wall thickness of the hollow sections produced, a central alignment of the container holder to the pressing tools is important.
DE 39 01 961 A1 describes a horizontal extrusion press with an axially displaceable container holder and running bar in the press frame between lower, weight-bearing guides and upper, hold-down guides. For the flush alignment of the container holder and the pressing tools, the container holder and the press frame are provided with adjustable guide shoes, which are resiliently connected to the container holder and the press frame by means of pressure elements and are held under the pressure force in positive-locking contact with the upper guides, wherein measuring sensors are provided between the container holder and the press frame for acquiring and indicating an inclination of the transducer axis. The measuring sensors are arranged on the upper, holding-down guide shoes to the container holder and to the running bar between the guide shoes and the container holder or running bar, as the case may be, carrying them, measuring and indicating the distance of the guide shoes to the container holder or running bar, as the case may be, parallel to the pressure elements, and the pressure elements are themselves designed as measuring sensors. In DE 39 01 961 A1, it is proposed that the measuring sensors be assigned measuring value indicators on the control stand of the press, which indicate any deviations that occur such that the operating personnel can recognize the extent of the deviations and, if necessary, carry out the corrections. Canting, asymmetrical thermal expansion or the like lead to a change in the distance between the end pieces of the container holder or the running bar and the sliding guides, such that the guide shoes are displaced under the effect of force from the disk spring assemblies provided on them. Although any angular and transverse deviations in the flush position of the transducer are reliably detected in this manner, detection takes place indirectly via the measuring sensors on the individual guide shoes, which makes automated monitoring and central alignment of the container holder along with the running bar of the press more difficult.
A generic method and such a press are also known from EP 3 677 356 A1.
Further prior art is known from documents EP 3 003 701 B1, CN 107243586 A, CN 201669364 U, JP 2020-99 930 A, U.S. Pat. No. 6,259,110 B1 and JP H04 141 337.
The disclosure relates to a method for monitoring and changing at least one component, for example a running bar or a container holder, slidingly guided between abutments of a press frame within the press frame. The disclosure relates in particular to a method for monitoring the position and changing the position of at least one component slidingly guided within the press frame between abutments of a press frame, in particular of a running bar and/or container holder, wherein the method comprises continuously measuring a central alignment of the slidingly guided component within the press frame and correcting the alignment of the slidingly guided component within the press frame as a function of the acquired measurement result by means of adjustable guide elements of the sliding guides of the press.
The disclosure further relates to a press having a press frame and having cross bars that absorb the press forces when the press is in operation, at least one component that is slidingly guided within the press frame, in particular a slidingly guided running bar, slide and/or container holder, having sliding guides provided on the guide columns, and having adjustable guide elements of the sliding guides.
The disclosure is based on the object of providing a method, which enables relatively simple monitoring of the central alignment of the components movably guided in the main axis of the press and automatically correcting the central alignment of such components.
The object is achieved with the features of the method as claimed. The object is further achieved by a press as claimed. Advantageous variants of the invention are covered by the respective subclaims.
According to one aspect, a method for monitoring the position and changing the position of at least one component, in particular a running bar, slide and/or a container holder, slidingly guided within a press frame between abutments of a press frame, is provided, wherein the method comprises continuously measuring a central alignment of the slidingly guided component within the press frame and correcting the alignment of the slidingly guided component within the press frame as a function of the acquired measurement result by means of adjustable guide elements of the sliding guides of the press, characterized in that the central alignment of the slidingly guided component within the press frame is measured by sensing the location of two reference points of the slidingly guided component in a plane extending transversely to the longitudinal center axis of the press.
A slidingly guided component, the central alignment of which is to be monitored and corrected by the method in accordance with the disclosure, can be, for example, a running bar of a press. However, the method is not limited to this; rather, the central alignment of a container holder on a press can also be monitored, displayed to a plant operator and/or automatically corrected by a corresponding open-loop or closed-loop control. By measuring the position of the reference points, the central alignment or position of the slidingly guided component, as the case may be, relative to the main axis of the press or to the longitudinal center axis of the press, as the case may be, can be determined in an X-Y coordinate system. By comparing the target position with the actual position of the coordinates of the reference points, the required correction of the alignment of the slidingly guided component can be determined. The method can be used regardless of the number of columns or pressure sleeves, as the case may be. This makes it possible to monitor and/or change the position of a guided component of, for example, a 2-column or 4-column press.
The fact that the measuring arrangement preferably senses a position deviation ≤2 mm, preferably ≤0.5 mm, even more preferably ≤0.1 mm, makes it possible to correct even small deviations and thus improve the repeatability of the pressing process.
The method in accordance with the disclosure has the advantage that the reference points or reference markings, as the case may be, provided, for example, on the running bar of the press can be sensed optically and thus over a certain distance. The reference points are preferably arranged at two points as far apart from one another as possible around the longitudinal center axis of the press and preferably in a plane extending transversely to the longitudinal center axis of the press.
For example, markings that can be sensed by laser can be used as reference points. The sensing of position or sensing the location, as the case may be, of the reference points preferably takes place by means of at least one measuring arrangement provided on the press frame. For example, an image-processing sensor system can be considered as a measuring arrangement. This can additionally be equipped with a laser triangulator for the acquisition of depth information.
In an advantageous variant of the method, it is provided that the guide elements of the sliding guide are adjusted automatically as a function of the acquired measurement result.
Preferably, the number of adjustment processes and/or the adjustment path covered and/or the position data associated with each adjustment process is captured in an open-loop or closed-loop control device. The open-loop or closed-loop control device can primarily be designed to initiate an adjustment process on the guide elements of the sliding guide automatically, i.e. without prompting by the operator. However, the open-loop or closed-loop control device can also output corresponding information to the operator, who then initiates an adjustment process. In addition, as mentioned above, the open-loop or closed-loop control device can also output information about the wear condition of the sliding guide.
Preferably, the press reshapes metallic materials. With this application in particular, the machining forces that occur are high and the required tolerances of the finished press components are low. The changing of position reduces wear on the press and can compensate for deviations in order to maintain the required component tolerances.
Preferably, the method is used in open-die forging, closed-die forging, isothermal forging, ring blanking, deep-drawing, extrusion and/or piercing or drawing presses, as the case may be.
According to a further aspect a press is provided, having a press frame and, during operation of the press, cross bars that absorb the press forces, at least one component, in particular a running bar and/or a container holder, which is guided in a sliding manner on guide columns within the press frame, having sliding guides provided on the guide columns, and having preferably automatically adjustable guide elements of the sliding guide, wherein, in order to carry out the method described above, at least two reference points, which are arranged at a distance from one another and can preferably be sensed optically, are provided on the slidingly guided component or on the running bar, as the case may be, in a plane extending preferably transversely to the longitudinal center axis of the press, and wherein at least one measuring arrangement for sensing the location of the reference points is provided on the press frame.
The press frame of the press can have as abutments, for example, a cylinder bar and a counter bar, which can be connected to one another by tie rods. The press can be designed as a horizontal or vertical direct extrusion press or horizontal or vertical indirect extrusion press.
The invention is explained below with reference to an exemplary embodiment shown in the drawings.
The guide element 10 comprises a housing 12, in which a spindle 13, which is rotatably mounted in a bushing 14, extends. The spindle 13 extends through first and second threaded bores 16,17 of an adjusting wedge 15, which is displaceable within the housing 12 by rotating the spindle 13. The thread of the threaded bores 16, 17 is a movement thread complementary to the thread of the spindle 14. The adjusting wedge 15 rests against a guide wedge 18, which is connected to a sliding block 19 or a sliding plate, as the case may be. The sliding block 19, which forms part of the sliding guide 6, is designed as a wear part and is adjustable parallel to the longitudinal center axis 4 or the main axis, as the case may be, of the press 1.
At its end projecting from the housing 12, the spindle 13 is provided with a contact 11 for the drive axle of a drive unit (not shown). For example, a drive unit can be a direct-acting electric motor or consist of a motor with a gearbox. To change the position of the sliding block 19, the spindle 13 is rotated with a corresponding drive unit. The rotary movement causes the adjusting wedge 15 to slide in or against the direction of the drawn arrow A, thereby causing the guide wedge to slide in or against the direction of arrow B and either increasing or decreasing the distance S between the guide columns 5 and the sliding block 19.
| Number | Date | Country | Kind |
|---|---|---|---|
| 10 2020 212 829.4 | Oct 2020 | DE | national |
This application is a national stage application, filed under 35 U.S.C. § 371, of International Patent Application No. PCT/EP2021/077879, filed on 8 Oct. 2021, which claims the benefit of German Patent Application No. 10 2020 212 829.4, filed 12 Oct. 2020.
| Filing Document | Filing Date | Country | Kind |
|---|---|---|---|
| PCT/EP2021/077879 | 10/8/2021 | WO |
