MACHINE ELEMENT

Abstract

A machine element, in particular for a shaping machine, having a lubricated bearing and/or a seal and at least one drainage conduit for catching a medium issuing from the bearing and/or the seal, preferably substantially pressure-lessly. A collecting device is provided for collecting the medium which is caught in the at least one drainage conduit over a period of time, and a measuring device is adapted to directly and/or indirectly measure an amount of the medium collected by the collecting device over the period of time.

Claims

1. A machine element, in particular for a shaping machine, comprising a lubricated bearing and/or a seal and at least one drainage conduit for catching a medium issuing from the bearing and/or the seal, preferably substantially pressure-lessly, and at least one collecting device for collecting the medium which is caught in the at least one drainage conduit over a period of time, and a measuring device adapted to directly and/or indirectly measure an amount of the medium collected by means of the at least one collecting device over the period of time.

2. The machine element according to claim 1, wherein the measuring device is adapted to measure the amount of the medium collected by means of the at least one collecting device during and/or after the period of time, wherein the period of time is preferably established in advance.

3. The machine element according to claim 1, wherein the measuring device is adapted on the one hand to measure a property, that varies with the amount of the collected medium, of the medium which is collected by means of the at least one collecting device and on the other hand to measure the period of time, wherein a measurement value of the period of time at a moment in time at which a measurement value of the property of the collected medium reaches and/or exceeds a limit value serves as a measurement in respect of the amount of the medium collected over the period of time.

4. The machine element according to claim 1, wherein the machine element is a hydraulic cylinder having at least one sealed pressure chamber.

5. The machine element according to claim 1, wherein the machine element is a rotary feedthrough, preferably with a plurality of mutually sealed media conduits.

6. The machine element according to claim 5, further comprising a plurality of mutually sealed media conduits, wherein there are separate drainage conduits for the various media conduits.

7. The machine element according to claim 1, further comprising a plurality of drainage conduits, with which separate collecting devices are respectively associated.

8. The machine element according to claim 1, further comprising a main drainage conduit in which separate drainage conduits are brought together, wherein the at least one collecting device is arranged in and/or at the main drainage conduit.

9. The machine element according to claim 1, wherein the at least one collecting device has at least one of the following: a stop valve arranged in the at least one drainage conduit, a pressure limiting valve arranged in the at least one drainage conduit, and/or a container connected to the at least one drainage conduit.

10. The machine element according to claim 1, wherein the measuring device has a pressure sensor for detecting a pressure in the at least one drainage conduit.

11. A shaping machine having a machine element according to claim 1.

12. A method of determining an amount of a medium issuing over a period of time from a lubricated bearing and/or a seal, wherein medium issuing from the bearing and/or the seal is collected over the period of time, and the amount of the medium collected over the period of time is directly and/or indirectly measured.

Description

BRIEF DESCRIPTION OF THE DRAWINGS

[0031] Further advantages and details of the invention will be apparent from the Figures and the related specific description.

[0032] In the drawing:

[0033] FIG. 1a shows a first embodiment of a rotary feedthrough according to the invention,

[0034] FIG. 1b shows a second embodiment of a rotary feedthrough according to the invention,

[0035] FIG. 2a shows an embodiment of a hydraulic cylinder according to the invention, and

[0036] FIGS. 2b and 2c show symbolic views of various configurations of a shaping machine according to the invention.

DETAILED DESCRIPTION OF THE INVENTION

[0037] The machine element 1 shown in FIG. 1a is a rotary feedthrough or union. It has a plurality of media passages 9 which are sealed off relative to each other by seals 3.

[0038] There are also a plurality of separate drainage conduits 5 which all open into a main drainage conduit 4.

[0039] In that respect it is to be mentioned that the main drainage conduit 4 can be composed of a main drainage passage in a component of the rotary feedthrough and a flexible or non-flexible conduit portion connected thereto, like for example a tube or a hose. In the present embodiment a stop valve which for example is in the form of a two-way valve serves as the collecting device 6. A corresponding stop valve can be actuated electrically or electronically, in which respect theoretically it is also possible to use a hand-operated stop valve. In addition there is a measuring device in the form of a pressure sensor.

[0040] The stop valve can be opened at regular intervals and thereafter it is possible by means of the pressure sensor to observe how quickly the pressure rises. If that occurs significantly faster than in previous observation cycles it is to be assumed that there is increased leakage.

[0041] It is to be noted that not all seals 3, media passages 9 and separate drainage passages 5 are provided with reference numerals in order to maintain clarity of the drawing.

[0042] FIG. 1b is a view similar to that of FIG. 1a, with the collecting device 6 being of a different configuration.

[0043] More specifically in FIG. 1b the collecting device 9 is formed by a pressure limiting valve. The pressure limiting valve can be set for example to about 0.5 bar above ambient pressure. When that pressure in the main drainage conduit 4 is reached the pressure limiting valve opens and the pressure in the main drainage conduit 4 fallstogether with the separate drainage conduits 5. That opening of the pressure limiting valve can be detected as a drop in pressure by way of the pressure sensor (measuring device 7). If the time between those activations of the stop valve decreases significantly it can also be assumed that there is increased leakage.

[0044] FIG. 2a shows an embodiment of the invention, the machine element 1 being a hydraulic cylinder having at least one sealed pressure chamber 8. At the side of the pressure chamber 8, that is remote from the seal 3, the drainage conduit 5 leads away, with pressure mediumin this case primarily hydraulic medium from the pressure chamber 8being caught in the drainage conduit 5.

[0045] The collecting device 6 and measuring device 7 according to the invention are of a similar structure to the example of FIG. 1a. Naturally it would also be possible to carry out measurement of the leakage rate as in FIG. 1b. Further examples are described in relation to FIG. 2b.

[0046] FIG. 2b is a purely diagrammatic view of a shaping machine 10 having a machine element 1 and a drainage conduit 5. Connected to the drainage conduit 5 is a container in which the medium leaking from the machine element 1 is collected, that is to say the container forms the collecting device 6. Two examples of possible ways of detecting the amount of medium in the container are illustrated. This would be on the one hand detecting the volume of the medium in the container by way of a float 7. (It will be appreciated that the level of the float has to be detected by way of a separate or integrated device. That however is not shown in the diagrammatic view in FIG. 2b.)

[0047] The second example would be a weighing device as the measuring device 7, on which the container is arranged. The mass of the medium in the container or a similar value can be detected by the weighing device.

[0048] The two embodiments illustrated in FIG. 2b can be used both with a measuring specification with a previously predetermined period of time and also with a limit value for the volume or mass.

[0049] FIG. 2c diagrammatically shows an embodiment of the invention, wherein a machine element 1 of a shaping machine 10 has a plurality of separate drainage passages 4. Each separate drainage passage 4 is connected for that purpose to a combination of collecting device 6 and measuring device 7 so that in this embodiment it is possible to precisely ascertain from which of the separate drainage passages 4 an increased leakage is coming. If an embodiment as shown FIG. 2c is implemented in an embodiment as shown in FIG. 1a or FIG. 1b it would thus be possible to establish the media passages 9 from which the increased leakage is originating.

LIST OF REFERENCES

[0050] Machine element 1 [0051] Bearing 2 [0052] Seal 3 [0053] Main drainage conduit 4 [0054] Separate drainage conduit 5 [0055] Collecting device 6 [0056] Measuring device 7 [0057] Pressure chamber 8 [0058] Media conduit 9 [0059] Shaping machine 10