SYSTEM FOR MONITORING STANDARD PARTS

Abstract

System for measuring misalignment of a tool (2) in a press device (1), the tool (2) comprises at least a first part (3) and a second part (4), which are movable relative to another in a guided manner by means of guide means comprising at least a guide pillar (10) provided in the first part (3) which is led in a guide bush (12) provided in the second part (4), wherein the system comprises measuring means (20) provided to detect misalignment of the tool (2). According to the invention, the measuring means (20) are mounted directly at the guide means.

Claims

1. System for measuring misalignment of a tool in a press device, the tool comprising a first part and a second part, which are movable relative to another in a guided manner by guide means comprising a guide pillar provided in the first part which is led in a guide bush provided in the second part, the system comprising measuring means adapted to detect misalignment of the tool, wherein the measuring means are mounted directly at the guide means.

2. System according to claim 1, wherein the measuring means are mounted at the guide pillar.

3. System according to claim 1, wherein the measuring means are mounted in a longitudinal bore provided in the guide pillar.

4. System according to claim 3, wherein the measuring means are fixedly secured in the longitudinal bore by means of holding elements.

5. System according to claim 1, wherein the measuring means are configured as a strain gauge sensor comprising a pillar shaped structure and at least one strain gauge attached to the pillar shaped structure.

6. System according to claim 5, wherein a pair of strain gauges are attached on opposite sides of the pillar shaped structure.

7. System according to claim 1, wherein the measuring means are configured as a capacitive sensor comprising a first cylinder with a first capacitive plate and a second cylinder with a second capacitive plate separated from each other by a distance (d).

8. System according to claim 1, wherein the measuring means are configured as a fiber optic sensor.

9. System according to claim 8, wherein the fiber optic sensor is configured as a low-coherence interferometric sensor.

10. System according to claim 1, wherein the measuring means are adapted to determine deflection and/or deviations from rectangularity of the guide pillar in respect of the first part of the tool.

11. System according to claim 1, wherein the measuring means are configured to determine deviations during set-up of the tool.

12. System according to claim 1, wherein the measuring means are adapted to be connected to a processing unit to transmit signals via wireless transmission.

13. System according to claim 1, wherein the measuring means are configured to determine a temperature of the guide pillar to which they are attached.

14. System according to claim 10, wherein the measuring means are adapted to determine magnitude and direction of the deviation from rectangularity.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0037] FIG. 1 shows a longitudinal section through a press device comprising a tool, in particular a first part and a second part, movable relative to another in a guided manner by means of guide means;

[0038] FIG. 2 is a perspective view of a longitudinal section through a sensor according to a first embodiment of the invention;

[0039] FIG. 3 is a perspective view of a longitudinal section through a sensor according to a second embodiment of the invention;

[0040] FIG. 4a is a schematic view of a guide pillar with a sensor according to a third embodiment of the invention;

[0041] FIG. 4b is a schematic view of the guide pillar with the sensor according to FIG. 4a in a deflected position.

DETAILED DESCRIPTION OF THE INVENTION

[0042] Shown in FIG. 1 is a die-set structure of a press device 1, comprising a tool 2. The tool 2 comprises depending on the complexitiy of the tool 2 a plurality of plates put together and made up of at least a first part 3 or first mold half and a second part 4 or second half mold, in particular a blanking or punching die or a mold. In FIG. 1 the die set structure comprises a matrix indicated by 8 and a die guide plate indicated by 9. The first and second parts 3, 4 of the tool 2 can be moved in a guided way by guide means relative to each other from a closed position to an open position and vice versa. In general, guide means are used in tool or injection mold constructions and in machine apparatus and device constructions when high guidance accuracy is required.

[0043] In tool 2 the first part 3, which can bear guide pillars 10, can be separated from the second part 4, which is provided with corresponding guides, particular guide bushes 12 for receiving the guide pillars 10 in which the guide pillars 10 are led, for example by means of ball bearings in cages.

[0044] If the die-set structure is used for a molding operation a mold can be attached on separating surfaces of the first part 3 and/or the second part 4 which is filled in the closed position of the tool 2 with a material to be formed like a cast material which is pressed into the mold, in particular in a horizontal direction. After opening the mold, the so-called preform can be removed from the mold.

[0045] Furthermore, the die-set structure can be used for a blanking and/or punching operation.

[0046] By setting-up the tool 2 in the press device 1 parallelism of surface pairs and of supporting surfaces have to be carefully maintained. FIG. 1 shows the tool 2 further comprising a die 5, in particular a stamping tool or punch, guided in the die guide plated 9. As illustrated in this figure deviation of the plates 3, 4 from congruency, backlash of the guiding of the tool 2 or deviation from angularity of the support of the guiding means can result in a tilted matrix axis 6. Further, if the guide means, in particular the guide pillars 10, are deflected and/or deviate from rectangularity further deviation from congruency and misalignement of the first part 3 and the second part 4 to each other can occur.

[0047] According to the invention, measurement means for measuring misalignment of a standard parts such as a guide pillar 10 are provided. Therefore, a longitudinal bore 14 extending from the one end of the guide pillar 10, e.g. a free end and coaxially to the guide pillar axis 16 is provided, wherein a diameter of the longitudinal bore 14 is smaller than a diameter of the guide pillar 10. Inserted into the longitudinal bore 14 is a measuring means (not shown) as described in detail later.

[0048] FIG. 2 shows a perspective view of a longitudinal section through a measurement means 20 according to a first embodiment of the invention. The measuring means 20 comprises a pillar shaped structure 22 on which a surface sensing element in form of a strain gauge 24 is attached, forming a strain gauge sensor. The measuring means 20 is configured to be inserted into the longitudinal bore 14 of the guide pillar 10 and to be fixedly mounted to the end regions of the guide pillar 10 by holding elements. Therefore, at end regions of the pillar shaped structure 22 ring shaped elements 26 can be provided, which come to abut against the end faces 11 of the guide pillar 10 when the pillar shaped structure 22 is fully pushed into the longitudinal bore 14 and can be fixedly mounted in position e.g. by press fitting.

[0049] At a circumference of the pillar shaped structure 22 at least one strain gauge 24 is provided. Preferably, two strain gauges 24 are attached in pairs on opposite sides of the pillar shaped structure 22 such that both can detect compression and tension depending on the direction of deflection of the guide pillar 10.

[0050] FIG. 3 shows a measurement means 20 according to a second embodiment of the invention wherein similar elements as in the first embodiment are characterized equivalently. The measurement means 20 is configured as a capacitive sensor 30 comprising a first cylinder 32 and a second cylinder 34 wherein a first surface of the first cylinder 32 provides a first capacitor plate 36 and a second surface of the second cylinder 34 provides a second capacitor plate 38 separated to each other by a distance d. If the guide pillar 10, in which the capacitive sensor 30 is embedded in any appropriate way in the longitudinal bore 14, is subjected to deformation or deflection the first and/or second capacitor plates 36, 38 will experience translation and/or rotation, which will affect the distance d and thus directly the determined capacitance of the capacitor sensor 30.

[0051] FIGS. 4a and 4b shows a measurement means 20 according to a third embodiment of the invention. The FIGS. 4a and 4b show schematically a guide pillar 10 in which a fiber optic sensor 40 is embedded in the longitudinal bore 14 coaxially with the guide pillar axis 16. The optical sensor 40 is configured as a fiber optic sensor, in particular as an interferometric sensor comprising a process unit 42 comprising inter alia an interferometer such as a Fabry-Pérot-Interferometer, a transducer to convert an optical signal into an electrical signal and a processor. For example light from a low-coherence source (not shown) is divided into a measurement fiber 44 and a reference fiber 46 arranged inside of the measuring means 20. The measurement fiber 44 is connected to the measuring means 20 such that during bending the measurement fiber 44 is elongated. FIG. 4a shows the guide pillar 10 in a straight position. FIG. 4b shows the guide pillar 10 subjected to deflection that can be detected by the fiber optic sensor 40.

[0052] Although the present disclosure has been described with reference to particular means, materials and embodiments, one skilled in the art can easily ascertain from the foregoing description characteristics of the present disclosure, while various changes and modifications may be made to adapt the various uses and characteristics as set forth in the following claims.