DE20003631U1 - Device for locating a movable body in a given space - Google Patents

Description

Kuhnke GmbH
Lütjenburger Strasse 101
23714 Malente

Device for locating a movable body in a given space

The invention is based on a device for locating a movable body in a given space with end faces by means of Maxwell fields that change depending on the position of the body in the space and can be measured and evaluated.

Such devices are used, among other things, on/in actuators that contain a body in a given space that can be moved translationally over a limited distance. Such a body is, for example, the piston or slide of an actuator unit, whereby the given space enclosing the body is formed from a cylinder tube made of a magnetically non-conductive material. The body that can be moved in the space is equipped with a permanent magnet to apply MaxwelF fields, the field lines of which penetrate the magnetically non-conductive room wall to the outside of the room. Outside the room, one or more sensors are arranged at a given location, which, when they reach the location, measure the room

The field lines penetrating the wall are detected and evaluated as a signal. The actuator can be fluidically or electrically operated.

A fluidically operated actuator has a piston that is radially pressure-tight and mounted in a translationally movable manner as a body that can be moved in space. A translational movement is forced upon the piston along its path of movement by alternating pressurization and pressure relief.

An electrically operated actuator of the type in question has, for example, a body that is guided along its path of movement and can be moved in translation, and which is held in place at its front ends by a deflection means. The deflection means can be, for example, a cable pull or a toothed belt that allows the carriage to perform a translational movement via the drive of an electric motor and in conjunction with a deflection roller. Preferably, the carriage is also equipped with a permanent magnet for signal interrogation, which interacts with a location-detecting sensor in a similar way to a fluidic actuator.

The disadvantage of these cited designs is that the sensor is arranged radially on the outer side of the space surrounding the body. The space required as a result makes the actuator with the mounted sensor unsuitable for radially restricted installation conditions.

Furthermore, devices for locating a movable body in a given space are known, with which a continuous query of the current position of the body in the space is possible. In a technically simple embodiment, the body has a sliding device that interacts with a linear potentiometer along the path of movement of the body in such a way that a location-related electrical resistance is set as a measurement signal.

The disadvantage here is that, on the one hand, the potentiometer is subject to wear due to the grinding device on the resistance track, and, on the other hand, that a considerable amount of equipment is required to encapsulate this measuring system sufficiently against environmental and pollution influences, which occur especially within the room, so that no unwanted changes in resistance occur.

DE 31 16 333 C2 describes a device of the type mentioned, which determines the position of the body in a room using a transmitting/receiving device. Here, a transmitting and receiving device is adapted to the room, whereby sound waves, light waves or magnetic waves are specifically emitted and reflected by the body. The emission occurs in pulses. By measuring the travel time of the signal, a conclusion can be drawn about the current location of the movable body in the room. The disadvantage of this design is the considerable amount of equipment and measurement technology required. Furthermore, this measuring arrangement requires a certain minimum distance between the body and the device emitting the waves.

DE 31 23 572 C2 discloses a device for locating a moving body, in which groups of magnetic storage tracks are applied to a carrier along the path of movement of the body. The location-related dependency of the body is recognized and evaluated by a read-write-erase head. This makes it possible to optionally write, erase and rewrite individual groups of tracks from outside the room using appropriate codes or programs. This design also requires equipment and measuring technology.

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The object of the invention is to propose a device for locating a moving body in a given space, which enables wear-free, point-by-point or continuous measurements with high accuracy and at the same time is protected against environmental influences in the broadest sense. In addition, the device should not increase the radial dimensions of an actuator along the path of movement of the body in space. Furthermore, it should be inexpensive to manufacture and suitable for large series.

The object is achieved in that at least one flux guide device conducting Maxwell fields is assigned to the room along at least part of the possible movement path of the body in the room, that the respective location-defining field exits the flux guide device at the front or at least near one front side of the room, furthermore that the location-defining field is detected by a sensor assigned outside the room, on the exit side of the field from the flux guide device, and an evaluation circuit arranged downstream of the sensor is arranged at the front or at least near one front side of the room and the sensor.

The inventive concept is described below using a fluidic actuator, a so-called piston-cylinder unit, as an example. In such a piston-cylinder unit, the space is formed, for example, by a circular or elliptical cylinder tube with a predetermined wall thickness and corresponding longitudinal extension made of magnetically non-conductive material. A translationally movable body in the form of a piston is arranged within the space, which is connected, for example, to a piston rod emerging from the space to release force. The end faces of the cylinder tube that axially delimit the space are each sealed pressure-tight with a closing part, a so-called cylinder cover, with at least one of the closing parts having an opening through which the piston rod penetrates from the inside of the space to the outside.

In order to implement the inventive concept in a first embodiment, the cylinder tube is made of a magnetically non-conductive material, as are the end parts on the front. By means of appropriate fluidic control, the body moves in space, forming two changeable spaces. This change in the size of the space takes place in the longitudinal extension of the space while the cylinder tube inner diameter remains the same and is dependent on the current location of the body in space.

Separated from the space by a wall, the cylinder tube has flux guide devices, at least one of which terminates at one end of the tube. At this end of the flux guide device, a magnetic field is introduced onto the flux guide device, for example by a permanent magnet or an electromagnet, which spreads out within the flux guide device and allows stray fields to emerge on its surface. These stray fields are absorbed in the space by a flux guide device assigned to the movable body, fed into another flux guide device and fed to a sensor via the latter. The sensor and the magnet used are in turn operatively connected via another flux guide device, so that a closed circuit of magnetic flux is created. An evaluable signal is always given when this circuit is disturbed, i.e. interrupted or closed, strengthened or weakened. An interruption of this circuit can be achieved, for example, if one of the flux guide devices has a location-defined length that is shorter than the distance the body moves. If the body exceeds the length-limiting section of the flux guide device due to its movement, the flow circuit is interrupted and this is detected as a signal by the sensor. If the direction of movement of the body changes, the body moves back into the flow circuit and closes it, which inverts the signal of the interrupted flow circuit.

For example, if an actuator has several flux guiding devices, each of different lengths, each with an associated sensor, each of these flux guiding devices is also assigned at least one defined signal, depending on the location of the movable body.

In another application, a transmission piece with high conductivity for the fields used is inserted between the flux guide device and the movable body. This transmission piece can be moved from the front sides along the movement path of the body and fixed at a predetermined location.

If the location of the transfer piece and the movable body match, an increased flow in the circuit results, which is detected by the sensor and fed to the evaluation circuit.

In yet another version, the piston-cylinder unit is provided with several movable, i.e. adjustable, transfer pieces. The adjustment to a specific location can be made from one or both ends of the piston-cylinder unit depending on the expediency or requirements. With such a piston-cylinder unit, for example, a defined stop position of the piston on the respective end part on the front side can be set and checked.

If the transfer pieces are set at locations before the piston's stop position, a useful signal is also emitted at these positions. This signal influences, for example, a valve that feeds a defined, controlled counterpressure into the space corresponding to the vent. This reduces the original kinetic energy of the piston, so that a relatively soft end stop occurs.

In a further embodiment, a location-related changing signal is produced over the movement distance of the body, whereby the current location of the body in space can always be localized. For example, one can proceed in such a way that the device generating the field, e.g. a permanent magnet, is assigned to the movable body and thus travels along the movement distance of the body along the axis of movement. The space is in turn operatively connected to at least one flux guide device, the flux guide device being designed in such a way that the stray fields emerging from the device generating the field have to overcome a measuring air gap that changes proportionally to the distance over the entire movement distance. This can be achieved by, for example, the movement distance of the body and the surface of the flux guide device forming the measuring air gap running at a predetermined angle in such a way that the signal measurable at the sensor changes as a preferably proportional signal, related to the distance to be traveled. This signal therefore provides continuous information about the current location of the body in space.

In yet another embodiment, the flow guide device is provided with alternating elevations and depressions at a defined distance, so that sensors receive a defined number of signals over the distance of movement. Conclusions can be drawn about the location of the body from the signals, and the speed of the body in space can be derived from the temporal pulse sequence.

In a further embodiment of the inventive concept, several flux guide devices are provided, each of which is in a corresponding operative connection with the device generating the field and provides different signals, possibly to different sensors, depending on the location. These different signals are fed to an evaluation circuit, the result of which defines the current location of the body in space. This can be done, among other things, by

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As the movement distance of the body increases, a measuring air gap increases depending on the location, while a further measuring air gap of another flux guide device decreases. As an example of a flux guide device with a changing air gap, a magnetically conductive component is selected which tapers in a wedge shape or cone shape according to the movement distance. Such a flux guide device is particularly useful when the movement distance is limited to short distances. If the movement distance is greater, it has proven useful to provide flux guide devices with elevations and depressions on their measuring surface at defined distances. As an example of a simple design, a magnetically conductive part with a round cross-section has been selected here, which has a thread-like structure with a defined outer surface and defined pitch. When passing through the body, defined pulse sequences are also emitted. Depending on the task, it is advantageous to use several measuring devices of this type at the same time, whereby a longitudinal offset of the elevation to be measured is preferably selected, for example in order to achieve a mutual phase shift of 90°. This - and the evaluation circuit - makes it possible to locate the body in space more precisely and to identify its direction of movement.

In another application, the piston rod of a fluidic actuator is designed as a movable flux guide device. In this case, the body is equipped with a device that generates the field, e.g. a permanent magnetic ring, in the manner described, so that part of the field is fed to the sensor via the piston rod and the piston rod-side end part, the cylinder cover penetrated by the piston rod. In this case, both the piston rod-side end part and the piston rod itself are magnetically conductive. Furthermore, at least one additional flux guide device is assigned, which either causes a changing measuring air gap or has elevations and depressions of defined distance on the surface to be measured.

An extremely compact design is achieved when both the device generating the field and the sensor measuring the field are arranged at the front of the room. It is particularly advantageous if at least the sensor and the evaluation electronics form a common unit, which if possible also accommodates the device generating the field, e.g. an electromagnet. Such a unit can be integrated in the closing part of the room to save space. Depending on the design, additional installation space can be saved by using a flexible circuit board for the evaluation circuit, the sensor and the device generating the field.

The device according to the invention for locating a movable body in a given space is of course not limited to fluidic actuators with a piston rod. Rather, it is also possible to determine the location of the body, for example, in a fluidic cylinder without a piston rod in a defined and continuous manner.

In another application, the inventive concept is used in a device with an electric motor drive, in which a translatory movable carriage is connected to a motor-driven driver unit. Here, the current location of the carriage can also be queried and the measured values are fed to the evaluation circuit.

In yet another embodiment, the proposed device is associated with a passive device that is driven by an actuator. An example is the mechanics of a boom whose movements are motor-driven or electromagnetic. Here, too, the current position of the boom or of a carriage that can be moved on the boom can be detected by a device of this type.

The device that generates the field provides so-called Maxwell fields as a measurement variable, which assume defined location-related variables at the location of the body in space and are recorded as such by the sensor. These fields can be electrical and/or magnetic in nature, whereby the sensors must be suitable for the respective operating principle.

Further advantageous embodiments emerge from the subclaims. The device for locating a movable body in a given space is described with the aid of the drawing in an exemplary application with a fluidic actuator, a so-called piston-cylinder unit.

Referring to the piston-cylinder unit, the reference symbols mean:

1 body moving in space = piston

2 movable flow guide device = piston rod

3 given space = cylinder space

variable space = variable cylinder space

4 circumferential transformation with finite longitudinal extension that radially limits the space = length-limited cylinder tube

the front side delimiting the length of the room

5.2 = Front side of the cylinder tube

End part closing off the room at the front = cylinder cover 6.2

7.1 Flow guidance device > Movement distance S of the body in space

7.2 Flow guide < Movement distance S of the body in space

7.3 Flux guide device with measuring surface at an angle to the X-X axis of motion 7.10

7.4 ditto 7.3

7.5 circular flux guide device, arranged at an angle α, β to the axis X - X

7.6 ditto 7.5

7.7 Flow guidance device with defined spaced elevations and depressions

7.10 Measuring surface of the flow guide device

8 Limitation of the measuring section for point signaling

9 device generating the field, e.g. permanent magnet, electromagnet, ...

9.1 ring-shaped, radial magnetic permanent magnet as piston magnet

10 Sensor

11 Flow control device for the return flow

11.1 Cylinder cover designed as a flow guide device

12 Evaluation circuit

13 Survey

14 Deepening

15 defined distance between elevation and elevation, or between depression and depression

16 Device generating the field, e.g. permanent magnet

Focusing means for the field (e.g. circumferentially pointed iron disk

18 Pulse sequence diagram

19 Cylinder tube wall

20 Transfer piece

21 Adjustment means

α, β Angular deviation of the measuring surface 7.10 of the flux guide device or the axes X«, Xp to the movement axis X-X

M ₁ - M ₄ location-defining, location-related changing measuring air gap

S Movement distance of the body in space = piston stroke

X-X axis of movement of the body in space = axis of movement of the

Piston in the cylinder chamber F _e field lines
X ₀ , Xß axes of the cross-sectionally symmetrical flux guide devices 7.5, 7.6

Show it:

Fig. 1 a piston-cylinder unit in longitudinal section in basic construction for point signal detection,

Fig. 2 and 3 each show an embodiment for a continuous location-based measurement of the piston in the cylinder chamber,

Fig. 4 shows an incrementally measuring version as a further embodiment, Fig. 5 shows the pulse diagram according to the structure of Fig. 4.

Fig. 1 shows a piston-cylinder unit consisting of a cylinder tube 4 of limited length, which accommodates a piston 1 in a radially sealed manner but which can move translationally along the movement axis XX. The piston 1 is connected to a piston rod 2 and the cylinder tube 4 is pressure-tightly sealed at its end faces 5.1 and 5.2 by a cylinder cover 6.1 and 6.2. The cylinder chamber 3 is divided by the piston 1 into the variable cylinder chambers 3.1 and 3.2. By alternately pressurizing the cylinder chambers 3.1 and 3.2 via the fluid connections A ₁ and A ₂ , the piston 1 is pressurized on one side while the other side is relieved of pressure, so that the piston travels through the movement distance S while releasing a usable force that can be tapped at the piston rod.

In order to make such a piston-cylinder unit accessible for position sensing of the piston, according to the example, the cylinder tube 4 is made of a magnetically non-conductive material, e.g. aluminum. The cover 6.2 and/or piston rod 2 are also made of a magnetically non-conductive material. At a suitable point, the cylinder tube 4 has longitudinally extending recesses into which, for example, round flux guide devices 7.1, 7.2 made of a magnetically conductive material, e.g. iron, are inserted.

The piston 1 is also made at least partially from a material that conducts magnetic field lines F _e . The flux guides 7.1 and 7.2 are introduced from the front side 5.1 into the cylinder tube 4. The flux guide device 7.1 extends, for example, over at least the entire length of the movement path S and ends flush with the front side 5.1. A further flux guide device 7.2 is introduced parallel to the flux guide device 7.1, the longitudinal extent of which is limited from the flush end of the front side 5.1 to its end 8. In order to enable position detection of the piston 1 within the cylinder tube 4, a device that generates MaxweH fields is required. This device is, for example, a permanent magnet 9, the north pole N of which comes into contact with the flux guide device 7.1 on the front side 5.1. The flux guide device 7.2 preferably has contact with a sensor 10 that detects Maxwell fields in the area of the front side 5.1. The sensor 10 is connected to the south pole S of the permanent magnet via a further flux guide device 11, preferably with contact. This results in a flow of the magnetic field lines F _e starting from the north pole N of the permanent magnet 9, through the flux guide device 7.1, the piston 1, and from there through the flux guide device 7.2, the sensor 10, the further flux guide device 11 to the south pole S of the permanent magnet 9. This creates a magnetically closed flux circuit.

It is also possible to use an electromagnet instead of the permanent magnet 9. Depending on the signal evaluation method selected, an electromagnet with a direct or alternating field can be used.

If the fluid connection A ₁ is pressurized and the chamber 3.2 is relieved of pressure at the same time, the piston 1 with the piston rod 2 moves in the direction of the cylinder cover 6.2, whereby the piston 1 passes over the end 8 of the flux guide device 7.2. As a result, the flow of the field lines at the end is significantly reduced or interrupted, which is detected by the sensor 10.

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This detection signal of the sensor 10 is electronically processed in an evaluation circuit 12 and made available as a useful signal.

In a preferred embodiment, the magnet 9, the sensor 10 and the evaluation circuit 12 are arranged on a common base plate. Both a pole of the magnet 9 and the associated sensor surface preferably touch the mutually facing end faces of the respectively associated flux guide device 7.1 or 7.2. Electromagnets are also sensibly arranged so as to touch the surface.

It is also possible to integrate several flux guide devices analogous to the flux guide device 7.2 in different longitudinal extensions into the cylinder tube 4, whereby a signal is generated at the respective end of the respective flux guide device when the piston passes through.

Depending on the operating principle, a sensor can be selected that either outputs an electrical signal, such as a Hall sensor or a field plate, or the sensor can also be of a fluidic type, so that a fluidic signal is provided. A correspondingly designed micromechanical sensor valve can be used as a fluidic sensor, the valve actuation unit of which is influenced by magnetic field lines, for example. The respective evaluation circuit is accordingly of an electrical or fluidic type. A fluidic evaluation circuit can, for example, consist of a miniaturized proportional valve that can be controlled by the micromechanical sensor valve.

Fig. 2 describes a piston-cylinder unit in which the current location of the piston 1 within the cylinder tube 4 can be continuously recorded. For this purpose, the flow guide devices 7.3 and 7.4 are introduced into the cylinder tube 4. These flow guide devices differ from those according to Fig. 1 in that the flow guide devices 7.3 and 7.4 have a

have a measuring surface 7.10 running at an angle α, β. This results in a continuously, preferably uniformly changing measuring air gap M ₁ or M ₂ over the entire movement distance. In this example, the piston 1 is equipped with a radially magnetized permanent magnet 9.1, the north pole of which emerges near the cylinder tube wall 19, while its south pole emerges near the piston rod 2. In order to obtain a closed magnetic flux circuit, the cylinder cover 6.2 is made of magnetically conductive material and is thus designed as a flux guide device 11.1. The piston rod 2 is also magnetically conductive. This arrangement described results in two fluxes of different intensity:

1. From the north pole N of the magnet 9.1, the measuring air gap Mi must first be overcome, after which the field lines penetrate into the flux guide device 7.3 and from there are fed via the sensor 10.1, the further flux guide device 6.2 (11.1), the piston rod 2 to the south pole S of the magnet 9.1.

2. From the north pole N, the field lines must overcome the measuring air gap M ₂ before they enter the flux guide device 7.4 and from there enter the south pole S again via the sensor 10.2, the further flux guide device 6.2 (11.1) and the piston rod 2.

It can be seen from Fig. 2 that the measuring air gaps M ₁ , M ₂ change continuously in opposite directions over the stroke. Depending on the task, the signals taken from the sensors 10.1 and 10.2 are fed to an electrical evaluation circuit, for example, the result of which represents the evaluation signal. The respective position of the piston can thus be recorded without contact over the entire movement distance of the piston within the cylinder tube. Here too, it is necessary that the cylinder tube 4 and the cylinder cover 6.1 are made of magnetically non-conductive material. The measuring air gaps M ₁ , M ₂ can be filled with any magnetically non-conductive substance.

Another embodiment analogous to Fig. 2 is shown in Fig. 3. Here, the flux guide devices 7.5 and 7.6 consist, for example, of cross-sectionally symmetrical, round, magnetically conductive material. The flux guide devices 7.5, 7.6 are introduced into recesses in the cylinder tube 4, whereby the recesses preferably run at an angle α, β, in relation to the movement axis X-X. The measuring function is ensured both when the angles α, β are the same or different. The cylinder tube 4 and cylinder cover 6.1 are made of magnetically non-conductive material, while the cylinder cover 6.2 is magnetically conductive and serves as a flux guide device 11.1. The piston rod 2 is also magnetically conductive.

Fig. 4 shows another application example. Here, two flux guide devices 7.7 are arranged parallel to the movement axis X-X and are provided with a profile with elevations 13 and depressions 14, at least on the measuring surface 7.10. The patterns of the elevations and depressions are preferably offset from one another by a quarter of a period in order to query and evaluate not only the location but also the direction of movement of the piston. In this embodiment, the number of elevations or depressions is counted over the movement distance S of the piston 1, resulting, for example, in a pulse sequence diagram according to Fig. 5. This arrangement makes it possible to use either the operating principle according to Fig. 1 or according to Fig. 2. The outer contour of the flux guide device 7.7 can, for example, be designed in the form of equally spaced depressions 14, comparable to a rack, but also in a round, cross-sectionally symmetrical design in the form of a thread with a defined pitch. In order to obtain a more precise statement about the piston position, it has proven useful to equip the piston with a focusing device 17.1, which is known per se. The field lines are bundled in this focusing device so that a clear recognition of the elevation or depression on the surface of the flux guide device 7.7 is achieved. By temporally administering and evaluating the counting pulses,

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Along the movement path, in addition to determining the location, the respective piston speed can also be recorded.

Fig. 6 shows an example in which the device for locating, in this case again a piston in a cylinder tube, where between the piston 1 equipped with a permanent magnet 9.1 and the flux guide device 7.2, a transmission piece 20 is inserted that can be adjusted over the movement distance S by an adjustment means 21, in this example by a threaded spindle. The transmission piece is magnetically conductive and bridges a large part of an otherwise large measuring air gap at its location. This results in an increased flux, which is detected by the sensor 9 and made available as a measuring signal.

Claims (18)

1. Device for locating a movable body ( 1 ) in a given space ( 3 ) with end faces ( 5.1 , 5.2 ) by means of Maxwellian fields which change depending on the location of the body ( 1 ) in the space ( 3 ), can be measured and evaluated, characterized in that at least one flux guide device ( 7.1-7.6 ) conducting Maxwellian fields is assigned to the space ( 3 ) along at least part of the possible movement path (S) of the body ( 1 ) in the space ( 3 ), that the respective location-defining field exits the flux guide device on the front side, or near at least one front side ( 5.1 , 5.2 ) of the space ( 3 ), furthermore that the field is detected by a sensor ( 10 ) assigned to the sensor outside the space ( 3 ) on the exit side of the field from the flux guide device, and a downstream evaluation circuit ( 12 ) is arranged on the front side or at least near a front side ( 5.1 , 5.2 ) of the room ( 3 ) and the sensor ( 10 ). 2. Device according to claim 1, characterized in that the flow guiding device ( 7.1-7.6 ) is at least partially separated from the space ( 3 ) by a wall ( 19 ). 3. Device according to one of the preceding claims, characterized in that the geometry of the flux guide device ( 7.3 , 7.4 or 7.5 , 7.6 ) is shaped or arranged in such a way that a location-related changing measuring air gap (M ₁ , M ₂ or M ₃ , M ₄ ) is formed between the body ( 1 ) and the flux guide device at least over a part of the possible movement distance (S) of the body ( 1 ) in the space ( 3 ). 4. Device according to one of the preceding claims, characterized in that the sensor ( 10 ) and the evaluation circuit ( 12 ) are a one-piece assembly. 5. Device according to one of the preceding claims, characterized in that the sensor ( 10 ) and the evaluation circuit ( 12 ) are at least partially arranged on a flexible printed circuit board as a one-piece assembly. 6. Device according to one of the preceding claims, characterized in that the body ( 1 ) within the space ( 3 ) is connected mechanically to at least one flux-conducting device ( 2 ) in a way that conducts the magnetic or Maxwellian fields, and that the flux-conducting device ( 2 ) penetrates at least one end ( 6.1 , 6.2 ) of the front side ( 5.1 , 5.2 ) in a movable manner to the outside of the space ( 3 ). 7. Device according to one of the preceding claims, characterized in that more than one flow guide device (7.1 and 7.2, or 7.3 and 7.4, or 7.5 and 7.6), each spaced apart from one another, is assigned to the space ( 3 ). 8. Device according to one of the preceding claims, characterized in that one sensor ( 10.1 , 10.2 ) is assigned to more than one flux-conducting device and that the measurement signals detected by the sensor ( 10.1 , 10.2 ) are formed as a resultant via a sensor bridge circuit and the resultant is further processed in the evaluation circuit ( 12 ). 9. Device according to one of the preceding claims, characterized in that the flux guiding device (7.5,7.6) is symmetrical in cross-section and the axis of motion (X X) of the space (3) to the center line (X_&alpha; X_&beta;) of the flow guide device (7.5,7.6) each run at an angle (α, β) such that between the body (1) and the flow guide device (7.5,7.6) over at least part of the movement distance (S) of the body (1) in the room (3) a location-dependent changing measuring air gap (M₃, M₄) is formed. 10. Device according to claim 9, characterized in that the angles (α, β) are at least approximately equal. 11. Device according to claim 9, characterized in that the angles (α, β) are different. 12. Device according to one of the preceding claims, characterized in that the measuring surface ( 7.10 ) of the flux guiding device ( 7.7 ) is provided alternately with defined spaced and shaped elevations ( 13 ) and depressions ( 14 ). 13. Device according to claim 12, characterized in that the elevations ( 13 ) and depressions ( 14 ) correspond at least approximately to the shape of a thread with a defined pitch. 14. Device according to claims 12 and 13, characterized in that the flux guiding device ( 7.7 ) is arranged parallel and spaced apart from the movement axis (XX). 15. Device according to claims 12 and 13, characterized in that the axes (Xα Xβ) of the flux guiding device ( 7.7 ) run at an angle (α, β). 16. Device according to one of the preceding claims, characterized in that at least one transmission piece ( 20 ) with high conductivity for the fields used is arranged between the flux guiding device and the movable body ( 1 ). 17. Device according to claim 16, characterized in that the transmission piece ( 20 ) is adjustable and fixable along the movement path (S) of the body ( 1 ). 18. Device according to claims 16 and 17, characterized in that the adjustment of the transmission piece ( 20 ) takes place from one end face ( 5.1 , 5.2 ).