DE102005051552B4 - Leakage monitoring device - Google Patents

Abstract

Leakage monitoring device, in particular for liquid supplies in machine tools, having a channel (3), which is provided for the passage of a leakage liquid with an inlet (5) and with an outflow port formed as outlet (6), and with a leakage liquid detection means (8) characterized in that the leakage liquid detecting means (8) for detecting a level of the leakage liquid is formed in a riser pipe (7) in liquid communication with the passing channel (3), and a flow rate regulator (9) is provided.

Description

The The present invention relates to a leakage monitoring device according to the preamble of claim 1.

to Detection of fluid leaks is the use of monitoring devices known. You are using a leakage fluid detection agent equipped by means of which the signaling of a occurred Leakage possible is. Such leakage monitoring devices Among other things, for monitoring of fluid supplies used by components in machine tools, for. For lubricating and / or coolant supplies and more.

For example, this describes EP 0 799 670 B1 under the specification of a constructive and simple as possible construction of such a leakage monitoring device for a machine tool with a rotatably mounted part. It consists of a so-called "mounting block" in which a channel is provided for the passage of a leakage fluid, in which project two electrodes. When a leak occurs, the leaking liquid flows through the channel, connecting the two electrodes in an electrically conductive manner. As a result, a voltage drop occurs at an electrical resistor connected in series with a voltage source between the two electrodes, which voltage drop is detected by a measuring instrument connected in parallel with the resistor. This in turn forwards a corresponding signal to a machine control unit for interrupting the current machining process.

Furthermore, the publications JP 61 159 129 A or JP 3274435 A different leakage monitoring devices are removed.

Task and advantages of the present invention

The The object of the present invention is a leakage monitoring device to improve the type set forth.

These The object is solved by the features of claim 1. In the dependent claims are advantageous and expedient developments of the invention.

Accordingly The invention relates to a leakage monitoring device, in particular for fluid supplies in machine tools, with one provided for the passage of a leakage fluid Channel and a leakage fluid detection means. It is characterized by the fact that the leakage liquid Detektionsmitttel a Level of leakage fluid captured in a riser and that a flow regulator is provided.

a such structure of a leakage monitoring device the realization is based on the fact that with many on a leakage to be monitored liquid supplies a permissible, minimum Leakage occurs, which is superimposed by certain level fluctuations can be. These level fluctuations in the leak have different causes. On the one hand are for it different operating conditions during the startup of the machine and the subsequent operating phase causally. On the other hand, there are also manufacturing tolerances individual components of the liquid supply and concomitantly changing during operation Make leakage cross sections. Another major cause is Impurities in the leakage fluid caused by clogging Such leakage cross sections a temporary damming of the leaking liquid cause, so after a flushing of the respective leakage cross-section a temporary, sometimes strong swelling in the level of the leaking fluid occurs.

Around these level fluctuations from the signaling of a serious To be able to hide leakage, was through the riser according to the invention a storage space or storage volume in the leakage monitoring device provided, which for buffering a temporarily increasing, however harmless amount of leakage fluid is designed. First after crossing a certain level in this buffer or storage volume a serious leakage is assumed and by the leakage fluid detection means triggered a signaling.

The Riser can be designed differently depending on the application be. In a first, simple embodiment, this may for example be a be outgoing from the channel bore, at least partially above of the channel, based on the installation position of the leakage monitoring device is located.

The Blanking allowed Level fluctuations can on the one hand on the volume design of the Rising pipe are influenced, on the other hand, by the type and detection position a leaking liquid through that provided leakage fluid detection means.

A further possibility of influencing the sensitivity, and thus to avoid a spontaneous, but incorrect leakage signaling due to a transient level fluctuation, consists in the design of the Ab flow cross section of the leakage monitoring device.

Here uses a flow rate regulator according to the invention, which either as an interchangeable element, each with a different flow cross section may be formed, or, where appropriate, even means for change having the flow cross-section.

One such flow regulator allows, for example, the use one and the same housing structure a leakage monitoring device for different use cases with different basic levels or different degrees fluctuating level of the monitored, leaking liquid.

to further operational improvement of the leakage monitoring device can these be equipped with a pollution protection, z. In the form of a sieve, a filter, a clarification chamber, in which heavy Can settle particles, and more.

ever according to embodiment and operation of the leakage liquid detection means may further be a vent for the Riser be provided so that the leaking liquid without back pressure in the riser can rise. To avoid a fluid discharge can this vent furthermore have a corresponding closure element, for. B. in the form of a vent at a corresponding level of flooding closing body. Preferably is its own weight so big that after lowering the level, the vent even with a slight adhesion effect is released again. For this ball shapes have particularly favorable proved, which have completely independent of location always the same sealing surface and thus reliably close a round hole.

The Leakage liquid detection means can in a first embodiment comprise at least one arranged in the riser electrical contact, which by immersion in the leakage liquid an electric Circuit closes. A second, also in contact with the leaking liquid End of this circuit is preferably also by means of a formed such electrical contact, which is not must necessarily be arranged in the riser to close the Circuit between these two contacts through the leaking liquid to enable. He just has to come in contact with her as well.

Around a reliable one Addressing the leakage monitoring device via a ensure a long period of time to be able to can such contacts with an alternating voltage, in particular an AC voltage are applied, the purity of the contact surface supported. In particular, in this case, a frequency in the range of about 560th kHZ regarded as advantageous, since these among other oxidation processes at the contact surface, for example, a brass contact and an associated Insulation layer structure at least reduced.

In Preferably, a switching contact can be provided in the following be that by closing or open the circuit described above undergoes a state change. in this connection it may be a changeover contact to a closer or around an opener. The particular advantage of such a contact lies in its potential freedom. Thus, this can with appropriate contact choice in each other circuit for triggering a signal or event due to over-leveling in the leakage monitoring device to get integrated.

to Detection of a level crossing the leaking fluid can different physical properties are used. In a first embodiment for example, the change an inductance be recorded. By closing a circuit due to a correspondingly high level of Licking liquid, such as described above, may be a change an inductance formed in this circuit can be achieved, which in turn then the above-described change of state of the electrical Switching causes.

In a modified embodiment thereof may instead of the inductance change also a capacity change be evaluated.

A another possibility The leakage detection is through the use of a pressure-sensitive Detector element. Particularly suitable for this purpose are pressure-sensitive Micro switches, which also provide potential-free switching contacts. As pressure to be detected, for example, the air pressure in the, in this case unilaterally closed riser be used, which by swelling of the leaking liquid in the riser through Reduction of the remaining air volume also accordingly increases. Such embodiments are very reliable, switch exactly and are also still inexpensive to produce.

Embodiment:

The invention will be apparent from the drawings and the description referring thereto her explained. Show it:

1 the structure of a Leckageüberwachunsgvorrichtung in a sectional view AA by a housing after 2 ;

2 an end view of the housing of the leakage monitoring device;

3 another sectional view BB and

4 a second end view of the housing of the leakage monitoring device.

1 shows the structure of a leakage monitoring device in a sectional view through a corresponding housing 2 , For the passage of a leakage fluid, corresponding to the directions of the arrows 4 , is a channel 3 with an inlet 5 and an outlet 6 intended. One with the channel 3 in liquid-conducting connection standpipe 7 forms a storage volume in which a certain amount of leaking fluid can be absorbed, which z. B. was caused by a transient level fluctuation of a leaking fluid. Thus, it is possible to mask level fluctuations of a leaking fluid to some extent from the signaling of serious leakage.

Only when a certain level is exceeded, such a serious leakage is assumed, so that leakage liquid detection means 8th address when exceeding this level.

In the present embodiment, the riser 7 as a bore in the housing 2 formed, with its level above that of the channel, based on the installation position of the leakage monitoring device. Another influence on the stowage behavior in the riser 7 is through one in the outlet 6 of the channel 3 arranged flow regulator 9 given. In the present example, this flow rate regulator 9 formed as an insert with a provided for a particular application, solid cross-section.

With a temporarily increased influx of leaking fluid this jams at the tapered outflow point using the channel volume up into the riser 7 , If the swelling of the leaking liquid is only a temporary event, this accumulated amount of liquid will flow off again over time, with a subsequent, usual inflow. By contrast, if, for example, there is damage in a supply system to be monitored, the level continues to increase until the leakage liquid detection means respond.

In order to avoid disturbances in the response of the leakage monitoring device, this further has a contamination protection 10 on, which here in the form of a filter and / or sieve insert in the inlet 5 is arranged.

In the present embodiment according to 1 is the riser 7 with a vent 11 provided, so that an unhindered rise of the monitored, leaking liquid in the riser is possible. To avoid an overflow of this leaking liquid and thus an exit from the housing 2 is hereinafter a closure element 12 intended for ventilation. In the present case, this is a spherical float 12 , which in accordance with increased liquid level in the vent formed as a bore 11 is pressed sealingly.

To detect a level to be reported of the leaking liquid in the riser 7 is in this at least an electrical contact 13 arranged. This is part of the leak fluid detection means 8th and closes by immersion in the leaking fluid along with another electrical contact 14 and the wires 15 an electrical circuit. This electrical circuit points at the end of the lines 15 , as shown in the 3 , an inductive electrical detector element 16 in the form of a coil. This coil changes its inductance abruptly as soon as the electrical contacts 13 . 14 be electrically connected by the leaking liquid.

This sudden inductance change causes one with the coil 16 coupled evaluation unit to change the switching state of an electrical contact. Preferably, this electrical contact is integrated in the evaluation and formed potential-free. Particular preference is given to the formation of an opener, thereby simultaneously monitoring a to the plug 18 connected cable to a possible interruption is possible.

The 2 and 4 each show an end face of the housing 2 , From the 2 is like in the 1 the training and arrangement of the riser 7 above the canal 3 seen. The 4 only serves to show the section plane BB.

1

Leakage monitoring device

2

casing

3

channel

4

arrow

5

inlet

6

outlet

7

riser

8th

Leakage liquid detection means

9

Flow regulators

10

pollution protection

11

vent

12

closure element

13

electrical Contact

14

electrical Contact

15

management

16

inductive detector element

17

evaluation

18

plug

Claims (12)

Leakage monitoring device, in particular for liquid supplies in machine tools, having a channel ( 3 ), which is for the passage of a leakage fluid with an inlet ( 5 ) and with an outlet ( 6 ) and with a leakage fluid detection means ( 8th ), characterized in that the leakage fluid detection means ( 8th ) for detecting a level of the leakage fluid in one with the passing channel ( 3 ) in liquid-conducting connection standpipe ( 7 ) and that a flow rate regulator ( 9 ) is provided. Leakage monitoring device according to claim 1, characterized in that the riser ( 7 ) at least partially above the channel ( 3 ) is trained. Leakage monitoring device according to claim 1 or 2, characterized in that a pollution protection ( 10 ) is provided. Leakage monitoring device according to one of the preceding claims, characterized in that a vent ( 11 ) for the riser ( 7 ) is provided. Leakage monitoring device according to one of the preceding claims, characterized in that a closure element ( 12 ) for venting ( 11 ) of the riser ( 7 ) is provided. Leakage monitoring device according to one of the preceding claims, characterized in that in the riser ( 7 ) at least one electrical contact ( 13 . 14 ) is provided, which closes an electrical circuit by immersion in the leakage liquid. Leakage monitoring device according to one of the preceding claims, characterized in that an exposure of an inadmissible leakage case in contact with the leakage fluid in contact electrical contact ( 13 . 14 ) is provided with an alternating voltage, one for the maintenance of the surface of the contacts ( 13 . 14 ) has favorable frequency. Leakage monitoring device according to one of the preceding claims, characterized in that a switching contact is provided, which by closing or opening of the electrical contacts ( 13 . 14 ) comprehensive circuit undergoes a state change. Leakage monitoring device according to one of the preceding claims, characterized that the switching contact is formed floating. Leakage monitoring device according to one of the preceding claims, characterized in that the leakage fluid detection means ( 8th ) an inductive detector element ( 16 ). Leakage monitoring device according to one of the preceding claims, characterized in that the leakage fluid detection means ( 8th ) comprises a capacitive detector element. Leakage monitoring device according to one of the preceding claims, characterized in that the leakage fluid detection means ( 8th ) comprises a pressure-sensitive detector element.