DE202020106000U1 - Meter counter - Google Patents

Abstract

Measuring device (10) for measuring an advance of a cable (2) of a sewer cleaning and / or sewer inspection system, comprising
- A compensation device (30), comprising
- At least one magnet (50; 50 ') rotatably mounted about an axis of rotation (DA; DA'), and
- A magnet holder (40) for receiving the at least one rotatably mounted magnet (50; 50 '), and
- A magnetic field sensor (60), wherein
- the cable (2) can be guided past the compensating device (30) when the cable (2) is advanced,
- The at least one rotatably mounted magnet (50; 50 ') is arranged on the magnet holder (40) in such a way that the advance of the cable (2) rotates the at least one rotatably mounted magnet (50; 50') about the axis of rotation (DA ; DA ') can be brought about, the magnetic receptacle (40) of the compensating device (30) being adapted to follow a movement of the cable (2) in the radial direction during the advance, and
- The magnetic field sensor (60) is arranged at a distance from the at least one rotatably mounted magnet (50; 50 ') and is adapted to detect the rotations of the at least one rotatably mounted magnet (50; 50'), the detected rotations being a measure of the Advance of the cable (2).

Description

Field of invention

The invention relates to a measuring device for measuring a feed rate of a cable of a sewer inspection and / or maintenance system.

Background of the invention

Sewer inspection and / or maintenance systems are introduced into a sewer and advanced or moved in the sewer in order to inspect or service or rehabilitate the sewer. Such sewer inspection and / or maintenance systems usually have cables or push rods, with which sensors and / or image recording devices can be advanced in the sewer.

Usually, the cable or the sliding eel is pushed into the canal or advanced in the canal by means of a propulsion device. The propulsion device can be a driven wheel or a driven belt. The cable touches the driven wheel or belt and is advanced due to the static friction between the surface of the cable and the wheel or belt. Such a propulsion device can be arranged, for example, on a carriage which is moved in the channel in order to advance or retract a cable or a push rod relative to the carriage. Such a propulsion device can, however, also be arranged on a cable drum, which is usually located outside the sewer shaft, in order to unwind the cable or the sliding shaft from the cable drum or to wind it onto the cable drum.

In the ideal case, the cable or the push rod is conveyed by the jacking device without errors and without wear. However, this ideal case rarely occurs in practice.

• - Der Durchmesser des Kabels / des Schiebeaals ändert sich über seine Länge, etwa aufgrund von Quetschungen.
• - Kabel / Schiebeaale unterschiedlichen Durchmessers sollen befördert werden.
• - Das Kabel / der Schiebeaal soll so befördert werden, dass das Kabel / der Schiebeaal nicht beschädigt wird. Insbesondere soll eine möglichst verschleißfreie Beförderung des Kabels / des Schiebeaals gewährleistet werden.
• - Während der Beförderung des Kabels / des Schiebeaals können sich die Reib- bzw. Hafteigenschaften des Kabels / des Schiebeaals ständig ändern. Die Reib- bzw. Hafteigenschaften hängen insbesondere von äußeren Umwelteinflüssen, etwa Verschmutzung ab. Die Reib- bzw. Hafteigenschaften können beispielsweise aber auch von der Steifigkeit und/oder von dem Mantelmaterial des Kabels / des Schiebeaals abhängen.

In practice, difficulties in conveying the cable or the pushing eel through the jacking device can consist of, for example:

• - The diameter of the cable / the sliding eel changes over its length, for example due to crushing.
• - Cables / pushing eels of different diameters should be transported.
• - The cable / push eel should be transported in such a way that the cable / push eel is not damaged. In particular, it is intended to ensure that the cable / push rod is conveyed with as little wear as possible.
• - During the transport of the cable / pushing eel, the friction or adhesive properties of the cable / pushing eel can change constantly. The friction and adhesive properties depend in particular on external environmental influences, such as pollution. The frictional or adhesive properties can, for example, also depend on the rigidity and / or on the jacket material of the cable / the sliding shaft.

• - Zwischen dem Kabel / dem Schiebeaal und der Vortriebseinrichtung entsteht ein Schlupf, sodass das Kabel / der Schiebeaal nicht mehr oder nicht wie gewünscht befördert wird.
• - Der Schlupf kann zu einem Verschleiß des Kabels / des Schiebeaals und/oder zu einem Verschleiß der Vortriebseinrichtung, insbesondere der Räder bzw. Riemen führen.

In practice, the difficulties mentioned usually have the following disadvantages:

• - There is a slip between the cable / pushing eel and the propulsion device, so that the cable / pushing eel is no longer transported or not transported as desired.
• The slip can lead to wear of the cable / the sliding shaft and / or wear of the propulsion device, in particular the wheels or belts.

Said slip arises when the static friction between the propulsion device and the cable / pushing shaft required for the effective advance of the cable / pushing shaft is not achieved, so that the wheel or belt rotates without further conveying the cable / pushing shaft. This results in the further disadvantage that the specific feed (i.e. the conveyed length in one and / or the other direction) of the cable / push rod can no longer be correctly determined. The exact position of, for example, the head of a sliding eel in the canal can no longer be determined under certain circumstances, which can mean that the exact position of damaged areas in the canal can no longer be determined either.

Another disadvantage of the slip is that the sliding friction that occurs between the propulsion device and the cable / push rod leads to undesired heat development. As a result, on the one hand, the cable / the sliding eel, in particular the jacket of the cable / the sliding eel, can heat up, so that breaks must be taken in order to cool down the cable / the sliding eel again. A heated cable / heated sliding eel can also be subject to greater wear than a non-heated cable / heated sliding eel. On the other hand, the propulsion device, i.e. heat the wheel or the belt strongly, which can lead to a considerable and rapid wear of the propulsion device.

The problem of heating also has a particularly negative effect if, for example, a trolley one Sewer inspection and / or maintenance system are to be used in an explosive environment, and the propulsion device is arranged on the carriage. The risk of explosion is then significantly increased.

Object of the invention

The object of the present invention is therefore to provide solutions which at least partially avoid the disadvantages known from the prior art and with which the actually conveyed length of a cable / a pushing eel can be determined more reliably.

Solution according to the invention

According to the invention, this object is achieved with a device according to the independent claim. Advantageous refinements and developments of the invention are given in the dependent claims.

• - eine Ausgleichseinrichtung, umfassend
• - zumindest einen um eine Drehachse drehbar gelagerten Magneten, und
• - eine Magnetaufnahme zur Aufnahme des zumindest einen drehbar gelagerten Magneten, und
• - einen Magnetfeldsensor, wobei
• - das Kabel beim Vorschub des Kabels an der Ausgleichseinrichtung vorbeiführbar ist,
• - der zumindest eine drehbar gelagerte Magnet derart an der Magnetaufnahme angeordnet ist, dass durch den Vorschub des Kabels Drehungen des zumindest einen drehbar gelagerten Magneten um die Drehachse bewirkbar sind, wobei die Magnetaufnahme der Ausgleichseinrichtung angepasst ist, einer Bewegung des Kabels in radialer Richtung während des Vorschubs zu folgen, und
• - der Magnetfeldsensor beabstandet zum zumindest einen drehbar gelagerten Magneten angeordnet ist und angepasst ist, die Drehungen des zumindest einen drehbar gelagerten Magneten zu detektieren, wobei die detektierten Drehungen ein Maß für den Vorschub des Kabels sind.

Accordingly, a measuring device for measuring an advance of a cable of a sewer cleaning and / or sewer inspection system is provided

• - A compensation device, comprising
• - At least one magnet rotatably mounted about an axis of rotation, and
• - A magnet holder for receiving the at least one rotatably mounted magnet, and
• - A magnetic field sensor, where
• - the cable can be guided past the compensating device when the cable is advanced,
• - The at least one rotatably mounted magnet is arranged on the magnet holder in such a way that the advancement of the cable can cause rotations of the at least one rotatably mounted magnet about the axis of rotation, the magnet holder being adapted to the compensation device, a movement of the cable in the radial direction during the Feed to follow, and
• the magnetic field sensor is arranged at a distance from the at least one rotatably mounted magnet and is adapted to detect the rotations of the at least one rotatably mounted magnet, the detected rotations being a measure of the advance of the cable.

The magnet mount of the compensating device is adapted to follow a movement of the cable in the radial direction during the advance in order to ensure that the rotation of the magnet is effected even in the event of a radial movement of the cable during the advance. a movement of the cable in the radial direction can be present, for example, when the cable moves away from the compensating device, past which the cable is guided during the advance.

• - ein Schwenken der Magnetaufnahme um eine Schwenkachse oder
• - ein lineares Verschieben der Magnetaufnahme

zu bewirken, wodurch die Magnetaufnahme der radialen Bewegung des Kabels folgt.The compensation device can comprise an actuator, in particular a spring element, acting on the magnet holder, the actuator being designed

• - A pivoting of the magnet holder about a pivot axis or
• - a linear displacement of the magnet holder

to effect, whereby the magnetic recording follows the radial movement of the cable.

The magnet holder can comprise a swivel arm, and the at least one rotatably mounted magnet can preferably be arranged at a free end of the swivel arm. “At a free end” means in the context of the invention that the magnet can be arranged in the area of the free end or in the vicinity of the free end.

It is advantageous if the actuator is arranged relative to the magnet receptacle in such a way that the application of an actuating force to the magnet receptacle presses the at least one magnet rotatably mounted on the magnet receptacle onto the passing cable. In one embodiment of the invention, the actuator can be arranged in or on the pivot axis.

The at least one rotatably mounted magnet can be arranged in a housing, the housing preferably having a rotationally symmetrical shape, in particular a cylindrical shape.

In one embodiment of the invention, the housing can have a rough surface. Depending on the material of the cable jacket, the static friction between the housing and the cable surface can be improved.

In one embodiment of the invention, the pivot axis can form the axis of rotation of the at least one rotatably mounted magnet.

• - das drehbar gelagerte Element mit dem zumindest einen drehbar gelagerten Magneten koppelbar ist, und
• - die Drehungen des drehbar gelagerten Elements durch die Kopplung mit dem zumindest einen drehbar gelagerten Magneten auf den zumindest einen drehbar gelagerten Magneten übertragbar sind, um den zumindest einen drehbar gelagerten Magneten zu drehen.

In one embodiment of the invention, the measuring device can comprise a rotatably mounted element which is arranged on the magnet holder in such a way that rotations of the rotatably mounted element can be brought about by advancing the cable, wherein

• - the rotatably mounted element can be coupled to the at least one rotatably mounted magnet, and
• the rotations of the rotatably mounted element can be transmitted to the at least one rotatably mounted magnet by coupling with the at least one rotatably mounted magnet in order to rotate the at least one rotatably mounted magnet.

It can be advantageous here if the rotatably mounted element is arranged on the free end of the magnet holder and the rotatably mounted magnet is arranged on the pivot axis of the magnet holder.

The magnetic field sensor can be arranged in a space having a negative pressure or an overpressure.

Furthermore, a system comprising two measuring devices according to the invention is provided, the two measuring devices being arranged on different sides of the cable, preferably on two opposite sides of the cable, and each being adapted to determine a measured value for a feed of the cable in relation to the respective measuring device , the advance of the cable in relation to the system being derived from the measured values determined, preferably by forming an average value from the measured values determined. Any measuring errors of a measuring device can thus be compensated for. Measurement errors can occur, for example, when the cable moves faster in the radial direction during the feed than the magnet holder can follow this radial movement - this can lead to brief deviations between the speed of rotation of the magnet and the feed speed of the cable.

Furthermore, a system is provided comprising two measuring devices according to the invention, one measuring device being arranged on a trolley of a sewer cleaning and / or sewer inspection system, and the other measuring device being arranged on a cable drum. “Arranged on a cable drum” means that the other measuring device is assigned to the cable drum. This allows the advance of a cable to be measured both on the cable drum and on the trolley. In the most favorable case, the deviation between the two measured feed rates is zero or at least negligibly small. If the two measured feed rates deviate from one another, measures can be taken to compensate for this difference again. For example, the advance on the cable drum can be accelerated if the advance measured on the cable drum is smaller than the advance measured on the carriage.

The cable can be a push rod or a power cable or a data cable or a combination thereof.

Figure list

• 1 ein Vortriebssystem zum Vorschub eines Kabels;
• 2 eine perspektivische Ansicht einer Ausgleichseinrichtung einer Messvorrichtung zum Messen eines Vorschubs eines Kabels;
• 3 die Ausgleichseinrichtung aus 2 in einer Ansicht von unten;
• 4 eine Schnittansicht der Messvorrichtung gemäß des in 1 gezeigten Schnittes A-A;
• 5 eine Schnittansicht der Messvorrichtung gemäß des in 1 gezeigten Schnittes B-B;
• 6 eine Ausgestaltung und deren Funktionsweise einer Messvorrichtung;
• 7 eine alternative Ausgestaltung und deren Funktionsweise einer Messvorrichtung;
• 8a eine erste Variante eines Verfahrens zur Erkennung eines Schlupfes beim Vorschub eines Kabels;
• 8b eine zweite Variante eines Verfahrens zur Erkennung eines Schlupfes beim Vorschub eines Kabels;
• 8c eine dritte Variante eines Verfahrens zur Erkennung eines Schlupfes beim Vorschub eines Kabels;
• 9 ein Blockdiagramm eines Vortriebssystems zur Erläuterung eines Verfahrens zur Reduzierung eines Schlupfes beim Vorschub eines Kabels;
• 10 eine alternative Ausführungsform eines Vortriebssystems; und
• 11 eine weitere alternative Ausgestaltung und deren Funktionsweise einer Messvorrichtung.

Further details and features of the inventions as well as specific, particularly advantageous exemplary embodiments of the invention emerge from the following description in conjunction with the drawing. It shows:

• 1 a propulsion system for advancing a cable;
• 2 a perspective view of a compensation device of a measuring device for measuring a feed of a cable;
• 3 the compensation device 2 in a view from below;
• 4th a sectional view of the measuring device according to FIG 1 Section AA shown;
• 5 a sectional view of the measuring device according to FIG 1 shown section BB;
• 6th an embodiment and its functioning of a measuring device;
• 7th an alternative embodiment and its functioning of a measuring device;
• 8a a first variant of a method for detecting slip when advancing a cable;
• 8b a second variant of a method for detecting slip when advancing a cable;
• 8c a third variant of a method for detecting a slip when a cable is being advanced;
• 9 a block diagram of a propulsion system for explaining a method for reducing a slip when advancing a cable;
• 10 an alternative embodiment of a propulsion system; and
• 11 a further alternative embodiment and its mode of operation of a measuring device.

Detailed description of the invention

In the following, exemplary embodiments of the invention are described using a cable. Instead of a cable, a sliding eel can also be used according to the invention. Furthermore will The following methods are described which only serve to illustrate the functionality of the system according to the invention.

The subjects of the present invention are in no way restricted to the exemplary embodiments described below, but rather serve to better understand the invention. Nevertheless, the objects and methods described below are advantageous embodiments of the invention.

If a “linear” advance of a cable or a pushing eel is referred to below, this means the advancement of a cable or a pushing eel, that is, the conveyance of the cable or a pushing eel along its longitudinal axis. In the context of the invention, this also means the unwinding or winding up of a cable or a push rod from a cable drum or onto a cable drum with the aid of a propulsion system.

In the following, “feed” always means conveying the cable or the pushing eel in one or the other direction relative to the jacking system. This means that during a feed, the cable or the sliding eel is pushed into the canal or pushed out of the canal (if the jacking system is in the canal, for example on a carriage) or pulled out (if the jacking system is outside the canal, for example located on a cable drum).

1 shows an embodiment of a propulsion system 1 for feeding a cable 2 a sewer cleaning and / or sewer inspection system.

With the jacking system 1 can the cable 2 forward (in the direction of the arrow P ) or backwards (against the direction of the arrow P ) are pushed or transported. With the cable 2 it can be a relatively rigid cable, whereby the propulsion system 1 also suitable for feeding less rigid or slack cables. With the jacking system 1 In particular, sliding eels can also be advanced, which are usually very rigid.

At the front end of the cable 2 Inspection units (for example cameras) or tools (for example grippers) can be arranged as well.

The jacking system 1 has a propulsion device 20th on. The jacking device 20th here has two wheels or rollers, at least one of the two wheels / rollers being driven. The cable is clamped between the two wheels. With the help of the driven wheels / rollers, which rest on the surface of the cable, the cable is moved when the wheels / rollers turn. The second wheel or the second roller serves as a counter wheel or counter roller that is not driven.

As an alternative to the two wheels / rollers, two drive belts can also be provided, one of the two belts also being driven here. But both belts can also be driven.

In yet another alternative, the propulsion device 20th have a roller / wheel and a belt, wherein preferably the belt is driven.

In yet another alternative, the propulsion device 20th a jaw drive to advance the cable 2 exhibit.

The embodiments of a propulsion device described above 20th have in common that at a feed of the cable 2 the feed force can be greater than the static friction between the propulsion device 20th and the cable 2 what a slip between the cable and the jacking device 20th may result. This is particularly the case (but not only) when the surface of the cable 2 or the rollers / belts / wheels are dirty or damp, so that the static friction between the propulsion device 20th and cables 2 is significantly reduced.

A challenge when feeding a cable 2 of a sewer cleaning and / or sewer inspection system is to prevent such slippage when the cable is advanced 2 to be detected as soon as possible after the occurrence in order to be able to intervene in the propulsion system to correct it, to adjust the rate of advance somewhat or to switch off the propulsion system in the event of extreme slip.

The propulsion device is used to recognize / detect a slip (hereinafter also referred to as slip detection) 20th adjusted, a first reading M1 of the feed. The first reading M1 indicates how far the jacking device 20th the cable 2 would have advanced under ideal conditions, ie without slippage. The first reading M1 can for example be derived from the number of revolutions of the drive wheels. The jacking device 20th has suitable detection means for this, which are known per se from the prior art. If there is a slip, the first measured value deviates M1 however, on the actual feed.

The propulsion system also includes 1 a measuring device 10 to measure the feed rate of the Cable 2 , where in 1 of the measuring device only the compensation device 30th you can see. With the measuring device, a feed of the cable becomes independent of the propulsion device 20th detected or measured.

The measuring device here has a compensation device 30th and a magnetic field sensor in 1 can not be seen on. The magnetic field sensor is adapted to rotations of a magnet, which is part of the compensation device 30th is to be detected, with the number of detected rotations of the magnet being a measure of the advance of the cable 2 can be derived. Based on the number of detected rotations of the magnet, the measuring device is independent of the propulsion device 20th a second reading M2 the feed ready. The second reading M2 indicates how far the cable is 2 was actually advanced. The measuring device is with reference to 2 to 7th described in detail.

The jacking system 1 also has an evaluation unit 80 (please refer 9 ), which is adapted to that of the jacking device 20th provided first measured value M1 and that of the measuring device 10 provided second measured value M2 to process. The procedural steps for processing the two measured values M1 , M2 and the resulting reduction in cable slip 2 are related to 8th described in detail.

The evaluation unit essentially calculates 80 a difference ΔM between the first reading M1 and the second measured value M2 , and compares this difference to a predetermined threshold T . Becomes the threshold T exceeded, there is a certain amount of slip, which should or must be reduced.

Is the amount of the difference ΔM equal to zero, then the cable is advanced without slippage. Is the amount of the difference ΔM between zero and the threshold T , then there is a slip that can be tolerated. In one embodiment of the invention it can be provided to reduce the slip even if the difference ΔM between zero and the threshold T lies so that a continuous regulation of the feed can be made.

To reduce the slip, the propulsion system includes 1 or the evaluation unit 80 a control device 90 , wherein the control device is adapted to the advance of the cable 2 through the jacking device 20th to control. In one embodiment of the invention, the advance of the cable 2 through the jacking device 20th be slowed down when the amount of the difference ΔM between the first reading M1 and the second measured value M2 the predetermined threshold T exceeds. But it can also be provided for the advance of the cable 2 through the jacking device 20th to slow down as soon as the amount of the difference ΔM between the first reading M1 and the second measured value M2 is greater than zero.

The control device 90 can be adapted to slow down the feed or the propulsion device so long, preferably to slow it down in stages, until the amount of the difference ΔM between the first reading M1 and the second measured value M2 the predetermined threshold T falls below or until the amount of the difference ΔM between the first reading M1 and the second measured value M2 is again zero or close to zero.

In an alternative embodiment, provision can also be made for the advance of the cable 2 to accelerate when the predetermined threshold T is exceeded. This may be necessary, for example, if the advanced cable lags behind another unit advanced in the channel due to the slip and the associated reduced advance speed, i.e. is advanced more slowly than the other unit due to the slip. For example, two cables can be pushed into a channel independently of one another, for example each with a jacking system shown here 1 . If a slip occurs on the cable in one of the jacking systems, while no slip occurs in the other jacking system, then the cable pushed forward by one jacking system remains behind the other cable. In order to catch up on this “residue” caused by the slip, the advance of the cable is accelerated.

In a further embodiment of the invention, the cable 2 with two independent jacking devices 20th be advanced. A propulsion device can be arranged on a carriage located in the canal, which for example pushes a sliding eel into a side canal. The other propulsion device can be arranged on a cable drum which is located outside the channel and which unwinds the sliding shaft from the cable drum and pushes it into the channel (in the direction of the trolley). Here it can happen that the advancing device of the carriage pushes the sliding eel into the side channel without slipping, while the advancing device of the cable drum pushes the sliding eel into the canal with slippage. In order to reduce the advance caused by the slip on the cable drum compared to the advance on the carriage, it can be provided to accelerate the advance by the advance device of the cable drum.

The jacking device 20th is therefore provided for the feed (in the direction of the arrow P or against the direction of the arrow P ) of the cable 2 to effect and at the same time a first measured value M1 that represents the target feed rate (the target feed rate can deviate from the actually effected feed rate (= actual feed rate) due to a slip). The measuring device 10 is therefore used to measure the effective advance of the cable 2 (= Actual feed rate, which is the second measured value M2 is provided), ie actually from the propulsion device 20th effected feed, provided. Will the cable 2 from the jacking device 20th If advanced without any slip, the two measured values give way M1 and M2 do not differ from one another, or only differ from one another by a negligibly small value.

As explained above, the control device 90 be adjusted to adjust the feed rate (speed up or slow down) if the difference ΔM between the first reading M1 and the second measured value M2 the predetermined threshold T exceeds. In one embodiment of the invention, however, it can also be provided to adjust the feed rate when the amount of the difference ΔM between zero and the threshold T is. For example, by accelerating the propulsion device (for example drive belt or drive wheel), if necessary, more static friction can again be established between the propulsion device and the push rod / cable, so that the difference before the threshold value is reached T can be compensated or reduced. Becomes the threshold T if exceeded, alternative measures can be initiated, for example the entire system can be switched off in order to avoid damage to the system and / or the push rod / cable.

In the following, with reference to 2 to 7th Refinements of a measuring device 10 shown. On the one hand, the measuring device 10 as with reference to 1 described, part of a tunneling system 1 and thus an essential contribution to the detection of cable slip 2 deliver. On the other hand, the measuring device can be used independently of a propulsion system for measuring an advance of a cable 2 be used.

2 shows a perspective view of a compensation device 30th a measuring device 10 for measuring a feed of a cable 2 .

The compensation device 30th includes one about an axis of rotation THERE rotatable magnets 50 and a magnetic holder 40 for holding the magnet 50 . The magnetic mount 40 is here as one about a pivot axis SA designed pivotable swivel device. An alternative embodiment of a compensation device 30th is related to 11 described.

The swivel device 40 points in the in 2 embodiment shown a swivel arm 41 on, at the free end of the around the axis of rotation THERE rotatably mounted magnet 50 is arranged. The swivel arm 41 we pivoted by applying a force. The actuating force is provided by an actuator or actuating means, for example a spring element. The positioning force acting on the swivel arm causes the free end of the swivel arm 41 and thus also the magnet located there 50 towards the cable 2 is pivoted.

The rotatable magnet 50 is designed here diametrically magnetized ring magnet, the magnet 50 can also be a diametrically magnetized disc magnet or can have another shape, as long as the magnet 50 perpendicular to the axis of rotation THERE is magnetized. The magnet 50 has at least one north pole and at least one south pole. In 2 is the magnet 50 on the underside of a rotatably mounted element 52 arranged.

The rotatable element 52 in this embodiment simultaneously forms a housing 51 in which the magnet 50 is arranged. The case 51 can generally be one around the axis of rotation THERE have rotationally symmetrical shape, the in 2 The cylinder shape shown is merely exemplary.

In one embodiment, the housing 51 have a concave curved surface that mates with a convex curved surface of the cable 2 is adapted so that the housing makes an effective contribution to guiding the cable 2 causes. Movements of the cable along the longitudinal axis of the housing 51 can thus be reduced or avoided.

When the cable is fed 2 becomes the cable 2 at the compensation device 30th passed by. The rotatable magnet 50 is in this way on the magnet holder 40 or on the swivel device 40 arranged that by the advance of the cable 2 Rotations of the magnet 50 around the axis of rotation THERE be effected. Furthermore, the magnet holder 40 or the swivel device 40 the compensation device 30th adapted to a movement of the cable 2 , in particular to follow a movement of the cable in the radial direction during the advance. This ensures that even with a radial movement of the cable 2 ie when the cable is away from the magnet 50 moved away, the rotation of the magnet during the advance 50 through the cable 2 is effected. In the in 2 embodiment shown touches the housing 51 or the rotatably mounted element 52 the cable 2 (please refer 1 ) so that the linear feed rate of the Cable 2 Rotations of the rotatably mounted element 52 and thus the rotatably mounted magnet 50 around the axis of rotation THERE causes.

3 shows the compensation device 30th out 2 in a view from below.

This view also shows an embodiment of the actuator 70 as a spring element. The swivel arm becomes the means of the spring force provided by the spring element 41 acted upon by an actuating force, which causes a pivoting of the pivot device 40 around the pivot axis SA causes. This ensures that the magnet mount 40 or the swivel device 40 the radial movement of the cable 2 follows as the on the swivel arm 41 acting spring force ensures the free end of the swivel arm 41 permanently against the passing cable 2 is pressed.

The magnet 50 is in one around the axis of rotation THERE rotatably mounted element 52 arranged, wherein the rotatably mounted element 52 a housing 51 for the rotatable magnet 50 forms and here at the free end of the swivel arm 41 is arranged. By the actuating force of the actuator 70 or the spring element 70 becomes the swivel arm 41 the swivel device 40 such in the direction of the cable 2 pressed that case 51 or the rotatably mounted element 52 the cable 2 touch. This causes a feed of the cable 2 the rotatably mounted element 52 or the housing 51 set in rotation, whereby also in the rotatably mounted element 52 or housing 51 arranged magnet in rotation around the axis of rotation THERE is moved.

In a further embodiment, the actuator 70 or the spring element 70 in the swivel axis SA be integrated, and thus also generate an actuating force that swivels the magnet holder 40 or the swivel device 40 around the pivot axis SA causes.

The position information "left", "right", "below" and "above" refer in the following to the cable to be fed 2 .

4th shows a sectional view of the measuring device 10 according to the in 1 shown section AA.

In the representation of the 4th is the compensation device 30th to the left of the cable to be fed 2 arranged. An arrangement of the measuring device would be equally conceivable 10 right, below or above the cable to be pushed 2 .

The magnet 50 is here in a housing 51 arranged, which in turn is rotatable about the axis of rotation THERE is stored. This is also the magnet 50 around the axis of rotation THERE rotatable.

In one embodiment of the invention, the magnet 50 Can be rotated around the axis of rotation even without a housing THERE be arranged on the pivot arm. This applies equally to all shown embodiments of the invention.

At a distance from the rotatable magnet 50 the compensation device 30th is the magnetic field sensor 60 arranged. The magnetic field sensor 60 is in this case arranged stationary, ie not movable, so that the magnet 50 relative to the magnetic field sensor 60 turns. In the in 4th The embodiment shown is the magnetic field sensor 60 below the magnet 50 arranged.

In the in 4th The embodiment shown is the magnetic field sensor 60 in an overpressure room 61 arranged. An arrangement in a room having a negative pressure is also possible.

It is advantageous if the magnetic field sensor 60 offset to the axis of rotation THERE of the magnet 50 is arranged. This ensures that the magnetic field sensor 60 the rotations of the magnet 50 , which is designed here as a diametrically magnetized ring magnet, can detect. The rotations of the magnet 50 cause in the measuring range of the magnetic field sensor 60 a change in magnetic flux over time, causing the rotations of the magnet 50 become detectable. The one from the magnetic field sensor 60 detected rotations are a measure for the advance of the cable 2 .

In a further embodiment not shown here, two measuring devices 10 be provided, with a measuring device 10 on one side of the cable 2 and the other measuring devices 10 on the other (opposite) side of the cable 2 are arranged. The magnetic field sensors 60 of the two measuring devices 10 can thus detect the rotations of the respective magnet independently of one another. From the two measuring devices 10 The measured values provided, a mean value can be formed, which is then used as a measure for the advance of the cable 2 can be used.

5 shows a sectional view of the measuring device or the compensation device 30th according to the in 1 shown section BB.

The swivel arm is clearly visible here 41 , at the free end of the magnet 50 is arranged. the magnet 50 is also here in a housing 51 housed, the rotatable about the axis of rotation THERE on the swivel arm 41 is arranged. The axes of rotation are also clearly visible here THERE offset arrangement of the magnetic field sensor 60 and the actuator 70 , this one from behind against the swivel arm 41 presses.

In a further embodiment of the measuring device 10 can the magnetic field sensor 60 on the magnet holder 40 or on the swivel arm 41 spaced from the magnet 50 be arranged. The one around the axis of rotation THERE rotatably mounted magnet 50 can alas in this embodiment at the free end of the swivel arm 41 be arranged. It can also be advantageous here if the magnetic field sensor 60 offset to the axis of rotation THERE of the magnet is arranged.

6th shows how the swivel mechanism works 40 an embodiment of the compensation device 30th .

The pivoting device is pivotable about the pivot axis SA arranged and comprises a pivot arm 41 . At the free end of the swivel arm 41 is a around an axis of rotation THERE rotatably mounted magnet 50 arranged, wherein the rotatably mounted magnet the cable 2 touched. At a distance from the rotatably mounted magnet 50 is a magnetic field sensor 60 arranged, which is adapted to rotations of the rotatably mounted magnet 50 around the axis of rotation THERE to be detected, the detected rotations being a measure of the advance of the cable 2 are.

With a radial movement of the cable 2 , shown in 6th The rotatably mounted magnet follows through the dashed lines 50 the cable 2 by pivoting the pivoting device 40 or by pivoting the swivel arm 41 around the pivot axis SA . The swiveling of the swivel arm 41 can by means of a on the swivel arm 41 acting actuating force F. be effected. The force F. can for example be provided by a spring element.

This ensures that the rotatably mounted magnet 50 the cable 2 even with a radial movement of the cable 2 touches the cable 2 with a feed, the rotatably mounted magnet rotates continuously 50 around the axis of rotation THERE causes.

The rotatable magnet 50 is mounted with as little friction as possible.

7th shows how the swivel mechanism works 40 an alternative embodiment of the compensation device 30th .

The swivel device 40 is also pivotable about the pivot axis here SA arranged and comprises a pivot arm 41 . According to this alternative embodiment, the magnet 50 ' rotatable around the swivel axis SA arranged. In this case, the axis of rotation DA ', about which the magnet can be rotated, agrees with the pivot axis SA match. The magnet 50 ' can also in this embodiment in a housing 51 be arranged.

In this alternative embodiment, the pivot arm is at the free end 41 an element rotatably mounted about an axis of rotation 52 arranged so that by the advance of the cable 2 Rotations of the rotatably mounted element 52 be effected.

The rotatable element 52 is with rotatable magnets 50 ' connectable or coupled. The rotatable element 52 and the rotatably mounted magnet 50 ' can be coupled via a belt, for example. The coupling allows rotations of the rotatably mounted element 52 on the rotatable magnet 50 ' be transmitted to the rotatably mounted magnet 50 ' to turn.

The magnetic field sensor 60 is at a distance from the rotatably mounted magnet 50 ' arranged, and adapted, rotations of the rotatably mounted magnet 50 ' to detect the axis of rotation DA ', the rotations detected being a measure of the advance of the cable 2 are.

With a radial movement of the cable 2 , shown in 7th through the dashed lines, the rotatably mounted element follows 52 by pivoting the swivel arm 41 the cable 2 . The swiveling of the swivel arm 41 can also be done here by means of an on the swivel arm 41 acting actuating force F. be effected. The force F. can for example be provided by a spring element.

This ensures that the rotatably mounted element 52 the cable 2 even with a radial movement of the cable 2 touches the cable 2 continuous rotations of the rotatably mounted element during a feed 52 around the axis of rotation THERE causes the rotations of the element 52 due to the coupling also rotations of the magnet 50 ' cause around the axis of rotation DA '.

8a shows a flowchart of a first variant of a method for detecting a slip when a cable is being advanced 2 .

In the method of reducing slip of a cable 2 becomes a first measured value M1 the advance of the cable 2 determined. Further becomes independent of the first measured value M1 a second reading M2 the advance of the cable 2 determined. The first reading M1 and the second reading M2 can be determined with a predetermined frequency. The second reading M2 represents the actual advance of the cable 2 (= Actual feed rate).

Between the first reading M1 and the second measured value M2 becomes a difference ΔM formed, and the advance of the cable 2 is adjusted (slowed down or accelerated) when the amount of the difference ΔM a predetermined threshold T exceeds.

In one embodiment of the method, the second measured value can M2 using the measuring device described above 10 be determined. To determine the second measured value M2 becomes a rotatable magnet 50 ; 50 ' on the cable 2 arranged by the advance of the cable 2 is rotated. There is also a magnetic field sensor 60 relative to the magnet 50 ; 50 ' arranged, with the magnetic field sensor 60 the rotations of the magnet 50 ; 50 ' are detected, so that the second measured value from the detected rotations M2 can be derived. This also applies to those with reference to 8b and 8c described procedure.

In an alternative embodiment of the method, the advance of the cable 2 be adjusted, preferably adjusted gradually, until the amount of the difference ΔM between the first reading M1 and the second measured value M2 the predetermined threshold T falls below again.

8b shows a variant of the method in which the measured values M1 and M2 the difference in the advance of the cable 2 represent over a predetermined time interval.

8c shows another variant of the method in which the measured values M1 and M2 the last measured feed of the cable 2 represent. The two variants are described below on the basis of a run through the process steps.

At the in 8b The variant shown can be the linear advance of the cable 2 for example be measured at a predetermined frequency. The values measured at the measuring time to for the first measured value M1 (t ₀ ) and the second measured value M2 (t ₀ ) of the advance of the cable are temporarily stored and made available. Likewise, the measured values at the current measuring time t ₁ , that is to say the first measured value M1 (t ₁ ) and the second measured value M2 (t ₁ ) for the advance of the cable 2 provided and cached. The first measured value is derived from the measured values provided M1 and the second reading M2 determined from the difference between the measured values at the current measuring time t ₁ and the measured values at the previous measuring time to. Thus represent the first measured value M1 and the second reading M2 in each case the distance of the cable that was linearly advanced in the last time interval between t ₀ and t ₁ 2 . Between the first reading M1 and the second measured value M2 becomes a difference ΔM formed, and the advance of the cable 2 will be adjusted when the amount of the difference ΔM a predetermined threshold T exceeds. Before the next run, the measurement values at the current measurement time t ₁ are temporarily stored as measurement values for the previous measurement time to.

At the in 8c The variant shown can be the advance of the cable 2 can also be measured at a predetermined frequency. The first measured value M1 and the second reading M2 determined and provided at the current measurement time. In contrast to the one in 8b shown variant is no longer required. Between the first reading M1 and the second measured value M2 becomes a difference ΔM formed, and the advance of the cable 2 will slow down when the amount of the difference ΔM a predetermined threshold T exceeds. In case of cable slippage 2 has been detected, the next test will be for a cable slip 2 the first reading M1 and the second reading M2 each reset to zero.

In a further variant, not shown here, the first measured value M1 and the second reading M2 can also be averaged from a plurality of measurements over a predetermined period of time, or filtered in some other way, in order to remove a noise of the first measured value M1 and / or the second measured value M2 to minimize.

9 shows a block diagram of a propulsion system 1 to explain a method for reducing slip when advancing a cable 2 .

The jacking device 20th of the jacking system 1 is adapted to a cable 2 to advance, taking a first reading M1 of the feed (= target feed) of the cable 2 to provide. Furthermore, the measuring device 10 of the jacking system 1 adjusted, a second reading M2 of the feed (= actual feed) of the cable 2 to provide.

The first reading M1 and the second reading M2 become an evaluation device 80 made available or handed over, with in the evaluation device 80 a difference ΔM between the first reading M1 and the second measured value M2 is formed.

In a variant of the method in which the first measured value M1 and / or the second measured value M2 As described above, the evaluation device can be determined or filtered from a plurality of measured values 80 also the first reading M1 and / or the second measured value M2 determine or filter from the majority of measured values.

The first reading M1 and the second reading M2 are determined at the same point in time or over the same period, so that the difference ΔM between the first reading M1 and the second measured value M2 when the cable is advanced 2 without slipping below a predetermined threshold T is essentially zero.

The evaluation device 80 is with a control device 90 coupled or connectable, so that between the evaluation device 80 and the control device 90 Data and possibly program commands can be exchanged. The control device 90 controls the advance of the cable 2 through the jacking device 20th . If the amount of the difference ΔM a predetermined threshold T exceeds, causes the control device 90 an adjustment V the advance of the cable 2 . By adapting V of the feed can be the slip of the cable 2 be reduced.

The evaluation device 80 and the control device 90 can be designed as a unit.

10 shows an alternative embodiment of the propulsion system 1 for feeding a cable 2 a sewer inspection and / or maintenance system. The cable 2 can also be a pushing eel here.

This in 10 shown driving system 1 includes a jacking device 20th to advance the cable 2 , which here includes a belt drive. The propulsion system also includes 1 a temperature sensor 15th , 15 ' , where the temperature sensor 15th , 15 ' in the area of the jacking equipment 20th or in the feed direction (arrow P ) of the cable 2 after the jacking device 20th is arranged.

The temperature sensor 15th is preferably adapted to a temperature of the cable 2 to detect. The temperature of the cable describes the externally determinable temperature on the surface of the cable 2 , essentially the temperature of the cable jacket or the jacket of the sliding shaft. The temperature sensor 15 ' is preferably adapted to detect a temperature of the propulsion elements, such as the belt of the belt drive.

The jacking system 1 also includes an evaluation device here 80 and a control device 90 . The temperature sensor 15th , 15 ' can the evaluation device 80 the detected temperature of the cable 2 or provide the propulsion elements. Here are the evaluation equipment 80 and the control device 90 can be coupled or coupled for the exchange of data. Furthermore, the control device 90 the advance of the cable 2 through the jacking device 20th Taxes. The evaluation device 80 is adapted to check whether the detected temperature is above or below a predetermined threshold value T lies. The control device is also adapted to the advance of the cable 2 through the jacking device 20th adjust when the detected temperature exceeds the predetermined threshold T exceeds.

The temperature sensor 15th , 15 ' can measure the temperature without contact, for example using an infrared measurement.

The control device is preferably 90 also adjusted here, the advance of the cable 2 through the jacking device 20th to adapt, preferably to adapt gradually, until the detected temperature exceeds the predetermined threshold value T falls below again.

For detection of slippage when a cable is being fed 2 can be the measured temperature of the cable 2 or the feed elements provide information about the existence of a slip, since the cable 2 or the feed elements can be heated quickly and to high temperatures in the event of a slip. In the event of a slip, an adaptation, in particular a slowing down of the feed, brings about an immediate reduction in the slip and thus a significant reduction in the temperature of the cable or the feed elements.

The method can be adapted such that when a slip is detected, the feed is adapted, preferably adapted in stages, until the measured temperature reaches the predetermined threshold value T falls below again.

11 a further alternative embodiment and its mode of operation of a measuring device.

The compensation device 30th the measuring device 1 also includes a magnet holder in this embodiment 40 who have an arm here 41 includes. At the free end of the arm 41 that the cable 2 facing is a magnet 50 arranged, which is rotatable about an axis of rotation THERE is stored. The arm 41 according to this embodiment itself is essentially perpendicular to the cable 2 aligned and linear (in the direction of the arrow P ) movably mounted. As with the configurations of the measuring device described above 1 has the measuring device 1 also here a magnetic field sensor 60 on, which is spaced from the magnet 50 is arranged such that the magnetic field sensor 60 Can detect rotations of the magnet.

The magnetic mount 40 or the arm 41 is having an actuating force F. urged to the arm 41 towards the cable 2 to move and thereby the magnet 50 against the cable 2 to press. The actuating force vector F. is thus essentially perpendicular to the longitudinal axis of the cable 2 . For the application of the magnet holder 40 or the arm 41 with the actuating force F. an actuator, for example a spring element, can be provided.

The one on the magnetic mount 40 or on the arm 41 Acting actuating force causes the magnet 50 radial movement of the cable 2 follows so that it is ensured that the magnet 50 always rests on the cable and the cable, regardless of a radial movement, the magnet during a feed 50 turns. In the 11 Units shown as dashed lines show a radially moved cable 2 and the compensating means followed the radial movement of the cable 30th .

According to all of the embodiments described above, the compensation device 30th designed so that at least the magnet 50 radial movement of the cable 2 can follow, ie if the cable moves to the right while it is being fed, the magnet follows this movement and also moves to the right, so that the magnet is always in contact with the cable.

List of reference symbols

1

Propulsion system

2

electric wire

10

Measuring device

15, 15 '

Temperature sensor

20th

Propulsion device for advancing the cable 2

30th

Compensation device

40

Magnet mount (e.g. swivel device with swivel arm)

41

Arm or swivel arm of the magnet holder 40

50, 50 '

rotatably mounted magnet

51

casing

52

rotatable element

60

Magnetic field sensor

61

Room exhibiting negative pressure / positive pressure

70

Actuator, e.g. Spring element

80

Evaluation device

90

Control device

A-A

Section A-A

B-B

Section B-B

DA, DA '

Axis of rotation

F.

Actuating force

LA

Longitudinal axis of the cable 2 or the jacking system 1

M1

first measured value of the feed of the cable 2

M2

second measured value of the feed of the cable 2

P

Arrow; Feed direction of the cable 2

SA

Swivel axis

T

Threshold

V

Adjusting (slowing down / accelerating) the cable 2

ΔM

Difference between the first measured value M1 and the second measured value M2

Claims (10)

Measuring device (10) for measuring a feed rate of a cable (2) of a sewer cleaning and / or sewer inspection system, comprising - a compensation device (30), comprising - at least one magnet (50; 50 'rotatably mounted about an axis of rotation (DA; DA') ), and - a magnetic mount (40) for receiving the at least one rotatably mounted magnet (50; 50 '), and - a magnetic field sensor (60), wherein - the cable (2) can be guided past the compensation device (30) when the cable (2) is advanced, - the at least one rotatably mounted magnet (50; 50 ') is arranged on the magnet holder (40) in such a way that, by advancing the cable (2), rotations of the at least one rotatably mounted magnet (50; 50') about the axis of rotation (DA; DA ') can be brought about, wherein the magnet holder (40) of the compensation device (30) is adapted to follow a movement of the cable (2) in the radial direction during the advance, and - the magnetic field sensor (60) is spaced apart from the at least one rotatably mounted magnet (50; 50 ') is arranged and adapted to detect the rotations of the at least one rotatably mounted magnet (50; 50 '), the detected rotations being a measure of the advance of the cable (2). Measuring device according to Claim 1 wherein the compensating device (30) comprises an actuator (70), in particular a spring element, acting on the magnet holder (40), the actuator (70) being designed, - pivoting of the magnet holder (40) about a pivot axis (SA) or - to cause a linear displacement of the magnet holder (40), whereby the magnet holder (40) follows the radial movement of the cable (2). Measuring device according to one of the preceding claims, wherein the magnet holder (40) comprises a swivel arm (41), and the at least one rotatably mounted magnet (50) is preferably arranged at a free end of the swivel arm (41). Measuring device according to Claim 2 or 3 , the actuator (70) being arranged relative to the magnet holder (40) in such a way that an actuation of the magnet holder (40) with an actuating force of the actuator (70) affects the at least one magnet (50; 50 'rotatably mounted on the magnet holder (40)) ) presses against the cable (2) that is passed by. Measuring device according to one of the preceding claims, wherein the at least one rotatably mounted magnet (50; 50 ') is arranged in a housing (51), the housing (51) preferably having a rotationally symmetrical shape, in particular a cylindrical shape. Measuring device according to one of the preceding Claims 2 to 5 , wherein the pivot axis (SA) forms the axis of rotation (DA ') of the at least one rotatably mounted magnet (50'). Measuring device according to one of the preceding claims, further comprising a rotatably mounted element (52) which is arranged on the magnetic receptacle (40) in such a way that rotations of the rotatably mounted element (52) can be brought about by the advance of the cable (2), wherein - The rotatably mounted element (52) can be coupled to the at least one rotatably mounted magnet (50; 30 '), and - The rotations of the rotatably mounted element (52) can be transmitted to the at least one rotatably mounted magnet (50; 50 ') by coupling with the at least one rotatably mounted magnet (50; 50'), around the at least one rotatably mounted magnet ( 50; 50 ') to rotate. Measuring device according to one of the preceding claims, wherein the magnetic field sensor (60) is arranged in a space (61) having a negative pressure or an overpressure. Measuring device according to one of the preceding claims, wherein the cable is a push eel. System comprising two measuring devices according to one of the preceding claims, wherein the two measuring devices are arranged on different sides of the cable (2), preferably on two opposite sides of the cable (2), and are each adapted to a measured value for a feed of the cable (2) in relation to the respective measuring device, the advance of the cable (2) in relation to the system being derived from the measured values determined, preferably by forming an average value from the measured values determined.

Images