CN107117462B - Device and method for determining the position and/or orientation of at least one suspended conveyor relative to a suspended feed unit - Google Patents

Abstract

The invention relates to a position determination device (20) for determining the position and/or orientation of at least one suspended conveying body (12) relative to a suspended feed unit (14), wherein the position determination device comprises a weight sensor unit which is designed to: a weight signal dependent on gravity is provided at a plurality of weight sensor positions, wherein the gravity is at least partially caused by the at least one suspended conveyance body and at least partially acts on the suspended conveyance unit. The position determining device according to the invention also has an evaluation unit which is configured to: based on the weight signal, a position or orientation of the at least one suspended conveyor body relative to the suspended feed unit is at least partially ascertained. The invention also relates to a method for determining the position and/or orientation of at least one suspended conveyor body relative to a suspended feed unit.

Description

Device and method for determining the position and/or orientation of at least one suspended conveyor relative to a suspended feed unit

Technical Field

The invention is based on the field of production control, in particular flexible conveying and positioning of production objects. The invention relates to a device and a method for determining the position and/or orientation of at least one suspended transport body relative to a suspended feed unit.

Background

Improved design and improvement of production control and production optimization can often be of great technical and economic significance in industry. Here, the concept "industrial 4.0" is a generic concept, which is combined with advances in these areas. The trend in this technical field can be here to manufacture lines up to the flexibility of such lines, which can individually manufacture individualized products.

Such a system is particularly interesting here: the system provides as many degrees of freedom of movement as possible for the items to be transported, for example up to three translational and three rotational degrees of freedom. Here, for example, a levitation feed unit can be used with which one or more transport bodies are levitated, i.e. lifted or floated, without contact, and can be fed in the feed direction. Here, the levitation feed unit can have a stator shoe system in which the magnet coils are arranged such that: the respective conveying bodies, which can also be referred to as "Mover movers", are made free-floating in accordance with the principle of magnetic levitation to be able to move and feed the tiles passing through the levitation feed unit and in this way to be accessible to different positions. Usually, the conveyance body is provided with a permanent magnet so as to be levitated by the levitation feed unit. Alternatively or additionally, however, a magnetic field generated by an electromagnet can also be used in the transport body. In general, the levitation feed unit can have an induction coil configured to: is flowed through by an electric current in order to suspend and supply a magnetic, in particular permanently excited, transport body in a contactless manner.

An exemplary levitation feed unit is described in WO 2013/059934 a 1.

The knowledge of the exact position or orientation of the conveying body relative to the levitation feed unit can be of great importance here in order to achieve an exact positioning and secure feeding of the conveying body. In particular, knowledge of position with sub-millimeter accuracy is necessary for some purposes.

In this case, a large number of hall sensors are usually used, which are typically arranged on the upper side of the levitation-supply unit, on which one or more transport bodies are to be levitated and transported. In this case, the hall sensor can be configured in a suitable manner for: the magnetic field caused by the suspended transport body is detected in a spatially resolved manner, and the position of the transport body is determined therefrom by means of the position of the hall sensor detecting the corresponding signal. In order to be able to determine the position of the suspended conveying body with high accuracy, a very high density of hall sensors or a very small spacing between adjacent hall sensors on the suspension feed unit can be required. In principle, it is suitable here that the smaller the distance between adjacent hall sensors, the higher the achievable accuracy of the position determination.

On the basis of the usually large number of hall sensors required, a levitation feed unit, which allows the position of the transport body to be determined with high accuracy, can thus require large manufacturing costs and/or large purchase and maintenance costs.

It is therefore desirable to provide a possible solution for determining the position and/or orientation of a suspended conveyor body relative to a levitation feed unit which requires little expenditure of cost and nevertheless allows the position and/or orientation to be determined with high accuracy.

Disclosure of Invention

According to the invention, a device and a method for determining the position and/or orientation of at least one suspended transport body relative to a suspended feed unit are proposed with the features according to the invention. Advantageous embodiments are the subject matter of the preferred and further embodiments and the following description.

In one aspect, the invention relates to a position determination device for determining a position and/or an orientation of at least one suspended conveyance body relative to a suspended feed unit, the position determination device comprising a weight sensor unit configured to: is arranged at the levitation feed unit and provides a gravity-dependent weight signal at a plurality of weight sensor locations, wherein the gravity is at least partially induced by the levitated conveyance body and at least partially acts on the levitation feed unit. The position determining device according to the invention also has an evaluation unit which is configured to: based on the weight signal, a position or orientation of the at least one suspended conveyor body relative to the suspended feed unit is at least partially ascertained.

In another aspect, the invention relates to a method for determining the position and/or orientation of at least one suspended conveyor body relative to a suspended feed unit, wherein the method comprises the steps of: providing a weight signal at a plurality of weight sensor locations along the levitation feed unit, wherein the weight signal is dependent on gravity, and wherein the gravity is induced by the levitated conveyance and acts at least partially on the levitation feed unit. The method further has the steps of: determining a position or orientation of the at least one suspended conveyance body based on the weight signal.

According to a preferred embodiment of the invention, the weight sensor unit can also have further components, such as, for example, wiring and/or shielding and/or fastening elements, in addition to one or more weight sensor elements. The evaluation unit can, for example, have a computing unit, for example a CPU or a computer, and can be connected to the weight sensor unit and, if present, to the magnetic sensor unit. Furthermore, the evaluation unit can also carry out other tasks, for example the control of the levitation feed unit, at which the position determination device is mounted.

The weight sensor unit and/or the evaluation unit and/or the position determination device can, for example, also be integrated completely or partially into the levitation feed unit. The evaluation unit can be integrated into a control element of the levitation feed unit, for example.

In a further aspect, the invention therefore relates to a feeding device for the controlled transport of at least one magnetic, in particular permanently excited, transport body, comprising a levitation feeding unit, wherein the levitation feeding unit is provided for: the at least one magnetic conveying body is suspended in a contactless manner and is fed along the feed unit in at least one feed direction, and the feed device according to the invention further comprises a position determination device according to the invention.

The invention provides the advantage that the position and orientation of the suspended conveyance body can be determined by means of the weight of the suspended conveyance body. In this case, the orientation is obtained, for example, if the gravitational force is not uniform over the area or base area of the transport body, or by means of a known/predefined geometric dimension of the at least one transport body, which can be detected by the sensor element and taken into account for determining the orientation. According to the invention, it is thus possible to determine the position and orientation of the transport body independently of the prevailing magnetic field. In this case, the device is not limited to a single determination of the position of the transport body, but rather can also determine the position and orientation of a plurality of transport bodies, preferably also one after the other and/or simultaneously. The invention has the advantage that for reliable position determination it is not necessary to use a magnetic field which is usually very dynamic, in particular formed by the magnet or magnets, usually designed as permanent magnets, in the conveying body and by the magnets, usually designed as electromagnets, of the levitation and supply unit. In this way, measurement inaccuracies, which can be caused by dynamic or locally and/or temporally strongly varying magnetic fields, can furthermore be reduced or avoided. Cumbersome coordination or calibration (as these are often necessary, when the position determination is carried out by means of measuring the magnetic field) is not required according to the invention or at least not in the same scale.

A further advantage of the invention is that the weight sensor unit of the position determination device according to the invention can be provided as a layer of its own or can have a layer which can be mounted, for example, at a conventional levitation feed unit. This allows, for example, the position determination device according to the invention to be used to retrofit existing levitation feed units, without the magnetic field caused by the levitation feed unit and/or by the transport body having to be taken into account in the optimization of the position determination device. In general, the position determination device according to the invention is preferably configured such that: so that the position determination can be carried out independently of the magnetic field present and the magnetic field preferably has no significant influence on the operation of the position determination device. Furthermore, it is possible that the position determination device is optimized independently of the levitation feed unit, in particular independently of the arrangement and design of the magnets of the levitation feed unit, and for the desired measurement accuracy.

Furthermore, the invention provides the advantage that the measurement of the weight force does not necessarily have to be carried out at the upper side of the levitation-supply unit, i.e. at the side on which the conveying body should be levitated (levitation side), but for example also at the lower side or at the side facing away from the levitation side, as long as the effect of the weight force of the levitated conveying body extends towards and/or is transmitted towards and/or causes a detectable effect at this location. For example, the weight force of the transport body acting on the levitation feed unit can be transmitted by the levitation feed unit to a weight sensor unit, which is arranged, for example, at the lower side of the levitation feed unit. For example, the weight of a conveyor body at its position relative to the levitation feed unit can cause a deformation of the individual components or the entire levitation feed unit at this position, which can also be determined at the lower side of the levitation feed unit.

Since the weight sensor unit is not necessarily arranged on the levitation side of the levitation-feeding unit, but can also be arranged at other locations, the subsequent installation in existing systems is facilitated and the levitation height or such a height can be lowered, for example, in keeping the same flying height of the levitated transport body: the transport body must be kept at this level by the levitation feed unit during levitation. This has the advantage that less effort is required for raising and maintaining the transport body at the flight level set for the transport than in the case of higher levitation heights, and therefore less energy consumption is required. Furthermore, a smaller levitation height can also lead to an improved stability of the transport body during levitation and/or during transport.

In an advantageous variant of the invention, it is also possible to install one or more weight sensor units at different locations at the levitation feed unit, for example, so that redundant measurement signals and/or greater accuracy can be determined.

In particular, it is not necessary according to the invention that the position determining device and/or the weight sensor unit is in mechanical contact with the conveying body, the position of which is to be determined. In fact, it is sufficient according to the invention that the weight force of the conveying body is transmitted to and/or acts on the levitation feed unit or the position determination device or the weight sensor unit by means of magnetic forces. This is done in particular by mechanical contact between the magnet element (in particular a coil) of the levitation feed unit carrying the transport body and the weight sensor unit.

It is a further advantage of the invention that the position determination device can be provided cost-effectively. For example, the weight sensor unit can be configured to: the weight signal is provided by means of a deformation of the coil layer of the levitation feed unit, in particular located inside it. In other words, the weight sensor unit can be set for: the deformation of the levitation feed unit is determined, which is caused by the transport body (whose position should be measured). Such deformations can often be measured by simple and/or cost-effective means, so that the acquisition and/or maintenance costs can be significantly lower for the position determination device according to the invention than for conventional position determination devices, which indicate the determination of the magnetic field, in particular for position determination. Such deformations can preferably be reinforced by installing magnetically active, e.g. magnetostrictive, materials, which further simplifies the measurement.

In a preferred manner, the weight sensor unit can at least partially have pressure-sensitive and/or force-sensitive and/or shape-change-sensitive and/or piezoelectric and/or piezoresistive and/or capacitive and/or inductive properties and/or have a material or element with such properties. For example, when the weight force of the conveying body acts on the weight sensor unit at the respective position, in this way an electrical signal (current or voltage) or a change in such a signal can be obtained, on the basis of which a weight signal for position determination can then be provided.

Here, the weight sensor unit can have a plurality of weight sensor elements which are arranged at a plurality of weight sensor positions of the levitation feed unit. Alternatively or additionally, the weight sensor unit can have a flat weight sensor element, which can be arranged flat on the levitation feed unit. For example, such a flat-construction weight sensor element can comprise one or more layers, for example having suitable properties as described above, in order to determine the gravitational force acting thereon. Preferably, the flat weight sensor element is configured such that: so that the occurrence of gravity can be ascertained from this position resolution at a plurality of weight sensor positions. In other words, the flat weight sensor element is configured in such a way that: so that the provided signal, which is formed by the weight force acting on it, also achieves the position at which the weight force acts on the flat-embodied weight sensor element. This can be achieved, for example, by a division or grid of the flat weight sensor elements, wherein the size of the division can be adapted to the desired resolution. In this case, for example, the individual segments can represent in each case one weight sensor position at which the weight force can be measured and the segments can be assigned locally to the presence of the weight force. Alternatively or additionally, a plurality of segments, which in particular abut one another, can also jointly represent a weight sensor position.

The division or the grid of the flat-structured weight sensor element is preferably realized by a column-like and row-like arrangement of electrodes (see fig. 5), wherein the electrodes defining the column are spaced apart from the electrodes defining the row in the measuring direction. The electrodes are preferably embedded in a material, such as a dielectric, which defines a resistance between the respective row and column electrodes, which resistance depends on the force of gravity at this location. This dependency is achieved in particular by deformation at this location.

Preferably, such a layer can be constructed very thin, in particular not thicker than 5mm, preferably not thicker than 1mm, particularly preferably not thicker than 0.5mm, still more preferably not thicker than 0.25mm, most preferably not thicker than 0.1 mm. In particular, such thin layers can also be suitable for: is arranged on the levitation side of the levitation-feeding unit and nevertheless achieves a reduction of the levitation height of the transporter relative to conventional position determination devices.

For example, piezoelectric layers can be used in order to generate an electrical signal when the pressure changes, the force changes or the shape changes. Alternatively or additionally, a piezoresistive layer can be used, which changes its electrical resistance when pressure, force or shape changes. Also other layers can be used which change their resistance when deformed, for example a combination of a flexible layer, for example from a polymer material, and a metal layer, for example platinum. The local electrical resistance of the metal layer at the weight sensor location is predefined at least in part by cracks and/or holes. The microstructure of the metal layer at the position of the weight sensor can be changed by deformation, so that the resistance is changed depending on the deformation. Here, preferably, a material or a structure is used: the resistance of which changes linearly or quadratically with the deformation, wherein other correlations can also be suitable. In this case, in particular, strain gauges or materials and/or devices which function according to the same or similar principles are used. Furthermore, it can also be advantageous to use a layer formed from a triboelectrically charged material, in which layer the internal contact caused by the gravitational force leads to an electrical signal.

Alternatively or additionally, a plurality of punctiform weight sensor units can also be used, which are each designed to: the gravity is measured point by point. In this case, the sensor density or the spacing between adjacent weight sensor units (as is also the case with the conventional use of hall sensors) must be selected in a suitable manner in order to achieve the desired resolution or accuracy in position determination.

Advantageously, position detection is also possible in the vertical arrangement of the levitation and supply units and in the corresponding movement of the transport body in the plane comprising the z-axis. In particular, in this case, the gravitational force acting at the center of gravity of the transport body results, via a lever effect conveyed by the magnetic force between the transport body and the levitation feed unit, in different forces in the horizontal direction acting at the magnet of the levitation feed unit, which can be detected by the deformation sensor element.

According to a preferred embodiment, the invention can also additionally comprise or be combined with a magnetic sensor unit which is configured to: providing magnetic signals dependent on magnetic forces at a plurality of magnetic sensor positions along the levitation feed unit, wherein the magnetic forces are at least partially caused by the levitated transport body and at least partially act on the levitation feed unit, and wherein the evaluation unit is further configured to: at least partially ascertaining a position or orientation of the at least one levitated transporter relative to the levitated feed unit based on the weight signal and the magnetic signal. In other words, the position determination device can be set such that: so that the evaluation unit uses not only the weight signal but also the magnetic signal in order to determine the position of the suspended conveying body. In this way, for example, redundant position determinations can be carried out, for example, in order to reduce susceptibility to interference. Such combinations can also be used, for example, to improve the position resolution and thus the accuracy of the position determination.

In particular, such a combination can be advantageous here: that is to say when a conventional levitation-feed unit with a hall sensor for position determination is extended with a position determination device according to the invention, which then can use the magnetic signal provided by the hall sensor in addition to the weight signal.

Further advantages and constructional aspects of the invention emerge from the description and the drawings.

It is clear that the features mentioned above and those yet to be explained below can be used not only in the respectively specified combination but also in other combinations or alone without departing from the framework of the invention.

The invention is schematically illustrated in accordance with an embodiment in the drawings and will be described in detail hereinafter with reference to the drawings.

Drawings

FIG. 1A shows a schematic view of a conventional feed device with a levitation feed unit and a conventional magnetic sensor unit in cross-section;

FIG. 1B shows a schematic view of a feeding set with a preferred embodiment of a position determining device according to the invention in a cross-sectional view;

fig. 2 shows a schematic view of the functional principle of a preferred embodiment of the position determination device according to the invention in a sectional view;

fig. 3 shows a schematic view of a further preferred embodiment of the position determination device according to the invention in a sectional view;

fig. 4 shows a schematic view of a further preferred embodiment of the position determination device according to the invention in a sectional view;

fig. 5 shows a schematic view of a further preferred embodiment of the position determination device according to the invention in a sectional view;

fig. 6 shows a schematic view of a further preferred embodiment of the position determination device according to the invention in a sectional view.

Detailed Description

The features of the different preferred embodiments can be combined with each other without departing from the idea of the invention. Identical or similar components are provided with the same reference numerals in the figures and are not explained several times in order to avoid repetitions. The figures are merely schematic representations which are not necessarily to scale to correctly reflect the size relationships between the individual components.

Fig. 1A shows a schematic representation of a feed device 10 in cross-section with a conveyor body or "mover" 12 suspended by a suspended feed unit 14 and capable of being transported in a feed plane 100 (perpendicular to the drawing). The levitation and supply unit 14 has a coil layer 16, in which magnetic coils (not shown) are arranged, by means of which magnetic fields can be generated for lifting or levitation of one or more transport bodies 12. The levitation is achieved by balancing and adjusting the attractive and repulsive magnetic forces between the respective conveying body 12 and the levitation feed unit 14, which are caused by the magnetic field generated in the coil layer 16 and the one or more permanent magnets 12a in the conveying body 12. The strength of the magnetic field or the strength of the magnetic force determines the levitation height 120 of the transport body on the levitation transport unit 14. The actual flight height 140 of the transport body 12 is determined here by subtracting the height or thickness of possible components, which are formed on the levitation feed unit 14, i.e. between the coil layer 16 of the levitation feed unit 14 and the transport body 12, from the levitation height 120.

The feeder 10 shown in fig. 1A has a magnetic sensor unit 18 on the levitation feed unit 14 for determining the position of the transport body 12 relative to the levitation feed unit 14 in a feeding plane 100. Here, the conventional magnetic sensor unit 14 has a plurality of hall sensors (not shown) which are arranged in the feeding plane 100.

Thereby, the flying height is reduced by the thickness of the magnetic sensor unit 18 in the conventional feeding apparatus 10. If, for example, a flight height 140 of at least 1.5mm is required for frictionless and interference-free transport of the conveyance body and if the magnetic sensor unit 14 has a thickness of the same 1.5mm, a levitation height 120 of at least 3mm is required. The coil layer 16 can have a thickness of 6mm, for example.

Fig. 1B shows a schematic view of a preferred embodiment of a feeding set 10 according to the invention with a preferred embodiment of a position determining device 20 according to the invention. The position-determining device 20 here comprises a weight sensor unit 22 and an evaluation unit 24. The weight sensor unit 22 is arranged in the embodiment shown on the underside of the levitation feed unit 14 and in particular below the coil layer 16.

The position determination is in this case not carried out by detecting the magnetic field induced by the feed body 12 at its position, but rather by detecting the force of gravity which is exerted or transmitted by the magnetic field between the respective feed body 12 and the coil layer 16 or by the magnetic force onto the coil layer 16. The weight sensor unit 22 is configured here for: the deformation of the coil layer 16 or the levitation feed unit 14 is detected at the position of the corresponding carrier body 12 based on the weight force or the pressure applied by the carrier body, which is applied to the coil layer 16 or the levitation feed unit 14 and at least partially transmitted to the weight sensor unit 22.

In particular, the weight sensor unit 22 does not have to be formed above the coil layer 16 in order to be able to detect deformations and/or pressures by the presence of the suspended conveying body 12 and to provide a weight signal based thereon. In particular, the pressure or deformation is greatest at the location of the levitation feed unit 14, at which or on which the conveyance body 12 is present. In this way, a weight signal can be provided by means of a position-resolved pressure or deformation measurement of the weight sensor unit 22, so that the evaluation unit 24 can determine or ascertain the position and/or orientation of the conveying body 12.

The advantage that is particularly visible in fig. 1B is that the flight height 140 is not reduced by the components to be mounted between the coil layer 16 and the carrier 12 and thus in the illustrated case the flight height 140 is equal to the levitation height 120. For this reason, the levitation height 120 can also be reduced to 1.5mm when, for example, a flying height 140 of 1.5mm is required, so that the energy consumption and the required magnetic field of the coils in the coil layers and the strength of the magnets 12a in the transport body 12 can be reduced and the stability of the levitation can be increased.

Fig. 2 shows a schematic view of the functional principle of a preferred embodiment of the position determination device 20 according to the invention. It is shown here that the presence of the suspended conveying body 12 at its location in the suspended feed unit 14 causes a deformation 200 based on gravity, which is at least partially transmitted to the weight sensor unit 22. The weight sensor unit 22 in this case has at least one weight sensor element or is divided into segments at a plurality of weight sensor locations 22a, so that at least one segment is associated with each weight sensor location 22 a.

For example, the size of the segments and/or the distance of the weight sensor positions 22a from one another can be selected such that: so that the deformation is detected only at the weight sensor position 22 a. The evaluation unit 24 then determines from the weight signal the position of the conveying body 12 in dependence on the weight sensor position 22a, at which the deformation was detected. Alternatively, the size of the segments and/or the distance of the weight sensor positions 22a from one another can be selected such that: so that, as shown in fig. 2, the deformation can be detected, preferably to different extents, at a plurality of weight sensor positions 22 a. In this case, the determination of the position and orientation of each transport body 12 can be effected particularly accurately, for example by taking account of a weighting of the detected deformations or by forming an average.

Fig. 3 shows a schematic view of a further preferred embodiment of the position determining device according to the invention, in which the weight sensor unit 22 is mounted on the upper side of the coil layer 16 or of the levitation feed unit 14 and is covered with a cover layer 26. It is to be noted here that the illustration in fig. 3 is not true to scale, but the thickness relationship between the individual layers can be configured differently than shown.

In particular, such an embodiment is particularly advantageous here: i.e. when the weight sensor unit 22 and the cover layer 26 are particularly thinly formed. This can be the case, for example, when using sensor cells with a thickness of less than 0.5mm or only 0.1mm and also when the cover layer 26 has a thickness of not more than about 0.25mm or 0.1 mm. However, in such a thinly constructed weight sensor unit 22 and cover layer 26, the difference between the flying height 140 and the flying height 120 can be kept small, in particular in comparison to the significantly greater thickness of a typically hall sensor layer (for example of the order of 1.5 mm).

In this case, the cover layer 26 can be designed such that: such that the cover layer reduces or prevents the risk of damage to the weight sensor unit 22 and/or the coil layer 16 due to mechanical effects and due to intruding fluids and/or particles. As long as the weight sensor unit 22 and/or the coil layer 16 consist of a plurality of tiles, an effective protection of the gaps between adjacent tiles can be facilitated in particular. Particularly advantageous can be a cover layer 26 which reduces the risk of intrusion of water and/or moisture and/or oxygen, so that degradation of sensitive components can be reduced.

Furthermore, the cover layer 26 can be designed to: effective protection against biological and/or chemical reactants is also formed. For example, the cover layer 26 can also be made of a particularly resistant plastic and/or of metal. A cover layer made of special steel is particularly advantageous, since even in small thicknesses this special steel offers effective protection before mechanical action and before fluids and particles.

In particular, in the case in which a robust cover layer 26 is constructed, the need for resistance of the weight sensor unit 22 and/or the coil layer can be small. For example, in this case too, a generally very sensitive piezoelectric polyvinylidene fluoride layer (PVDF layer) with metal contacts can be used in the weight sensor unit 22, which is typically susceptible to degradation in the event of oxidation or the ingress of moisture.

Furthermore, the position determining device 20 according to the invention in other preferred embodiments (not shown) can also have a plurality of weight sensor units 22 and/or a plurality of cover layers 26. For example, multiple weight sensor units 22 can be arranged at one side or different sides of the coil layer 16 and/or the levitation feed unit 14. Furthermore, a plurality of cover layers 26 can also be arranged on one side or on different sides of the coil layer 16 and/or the levitation feed unit 14 and cover one or more weight sensor units 22 or be arranged between a plurality of weight sensor units 22.

In fig. 4 to 6, further preferred embodiments of the position determination device 20 according to the invention are shown in cross-sectional views. In fig. 4, the position determination device 20 has, for example, a weight sensor element, for example a strain gauge, embedded in the material to be enclosed at a weight sensor location 22a, and an embedded structure or element 22 b.

In fig. 5, three further embodiments of the weight sensor unit 22 are schematically illustrated, which are separated on the image by vertical dashed lines. In any case, the weight sensor cell has a column electrode 22c and a row electrode 22d spaced from each other and from each other such that a respective one of the projected intersections between the column electrode 22c and the row electrode 22d is represented as a weight sensor position 22 a. According to a first variant (on the left), the weight sensor unit 22 has no additional embedded elements or structures. According to a second variant (middle), the weight sensor unit 22 has a structure 22b embedded at the weight sensor location 22 a. According to a third variant (on the right), the weight sensor unit 22 has embedded structures 22b outside the weight sensor position, i.e. each embedded structure 22b is located in projection onto a main plane of extension not only between two column electrodes 22c but also between two row electrodes 22 d.

In a further advantageous embodiment, the grids of the electrode and of the embedded structure are different, in order to thereby achieve a further improvement in the positioning accuracy.

The embedded structure or element 22b of fig. 4 and 5 can have a signal-supporting structure, for example a magnetically active (e.g., magnetostrictive) element, which changes its shape and/or size by the influence of a magnetic field from the suspended carrier and thereby induces a signal in the weight sensor unit 22. In addition to the weight-based deformation, which is transmitted to the weight sensor unit 22 by the deformation of the coil layer 16, the magnetic force-based deformation, which is caused by the magnetic force of the one or more permanent magnets 12a of the conveying body 12, thus also contributes to the weight signal. This is particularly advantageous for vertical arrangements, in which the gravitational force is vertically established on the magnetic force, since this improves the position and/or orientation determination.

Alternatively or additionally, the embedded structure or element 22b also has a sensitive or signal-generating structure, for example a magnetically sensitive (e.g. magnetoresistive) element, which changes its electrical resistance under the influence of a magnetic field from the suspended carrier. Such elements are part of a magnetic sensor unit 18 for generating a magnetic signal. This is particularly advantageous for vertical arrangements, in which the gravitational force is vertically established on the magnetic force, since this improves the position and/or orientation determination.

Fig. 6 shows a further preferred embodiment in which the coil layer 16 and the weight sensor unit 22 are structured. In particular, the respective individual coil element 16a is arranged at a weight sensor position 22a on an individual weight sensor element (vice versa) which is in turn arranged on a common carrier. The intermediate space can be filled, for example, with an optional buffer layer (e.g., epoxy) in order to hinder the intrusion of dirt or the like.

Claims (18)

1. A position determining device (20) for determining a position and/or an orientation of at least one levitated transport body (12) having one or more permanent magnets (12 a) relative to a magnetic levitation feed unit (14), the position determining device comprising:

a weight sensor unit (22) configured to: -arranged at the levitation feed unit (14) and providing a weight signal dependent on gravity at a plurality of weight sensor positions (22 a), wherein the gravity is at least partly caused by the at least one levitated transport body (12) and acts at least partly on the levitation feed unit (14);

an evaluation unit (24) configured to: based on the weight signal, a position and/or an orientation of the suspended conveying body (12) relative to the suspended feeding unit (14) is at least partially ascertained.

2. The position determining apparatus (20) according to claim 1, wherein the weight sensor unit (22) is configured to: the weight signal is provided without mechanical contact between the weight sensor unit (22) and the at least one suspended conveying body (12).

3. The position determining apparatus as claimed in claim 1 or 2, wherein the weight sensor unit (22) has at least one weight sensor element and/or a plurality of weight sensor elements of flat construction.

4. The position determining apparatus (20) according to claim 3, wherein said at least one weight sensor element is connected planarly to said levitation feed unit (14).

5. Position determining device (20) according to claim 3, wherein the at least one weight sensor element has at least partially pressure-sensitive and/or force-sensitive and/or shape change-sensitive and/or piezoelectric and/or piezoresistive and/or capacitive and/or inductive properties.

6. The position determining apparatus (20) of claim 3, wherein the at least one weight sensor element is set such that: such that the weight sensor element at least partially changes its electrical resistance when loaded with a mechanical force and/or when loaded with a mechanical pressure and/or in a mechanical deformation.

7. The position determining apparatus (20) according to claim 6, wherein the magnitude of the change in the electrical resistance is dependent on the magnitude of the pressure of the loaded machine and/or on the magnitude of the force of the loaded machine and/or on the degree of deformation of the machine.

8. The position determining apparatus (20) of claim 7, wherein the dependence is linear or squared.

9. The position determining apparatus (20) of claim 3, wherein the at least one weight sensor element is set such that: such that the weight sensor element generates an electrical signal when loaded with a mechanical force and/or when loaded with a mechanical pressure and/or in a mechanical deformation.

10. The position determining apparatus (20) according to claim 9, wherein the amplitude of the generated electrical signal depends on the magnitude of the pressure of the loaded machine and/or on the magnitude of the force of the loaded machine and/or on the degree of deformation of the machine.

11. The position determining apparatus (20) of claim 10, wherein the dependence is linear or squared.

12. Position determining device (20) according to claim 3, wherein the at least one weight sensor element is provided for being arranged at a side of the levitation feed unit (14) which side faces away from the levitation side of the levitation feed unit (14).

13. The position determining apparatus (20) according to claim 1 or 2, wherein the weight sensor unit (22) has a magnetically active material (22 b).

14. The position determining apparatus (20) according to claim 1 or 2, wherein the weight sensor unit (22) has a magnetostrictive material (22 b).

15. The position determining apparatus (20) according to claim 1 or 2, further comprising a magnetic sensor unit (18) configured to: providing magnetic signals dependent on magnetic forces at a plurality of magnetic sensor positions, wherein the magnetic forces are at least partially caused by the at least one levitated transport body (12) and act at least partially on the levitated feed unit (14), and wherein the evaluation unit (24) is further configured for: at least partially determining a position or orientation of the at least one levitated transport body (12) relative to the levitated feed unit (14) based on the weight signal and the magnetic signal.

16. A feeding device (10) for the controlled feeding of at least one magnetic conveying body (12), comprising:

a levitation feed unit (14) configured to: -suspending the at least one magnetic conveyance body (12) in a contactless manner and conveying it along the feed unit (14) in at least one conveying direction (100); and

position determining apparatus (20) according to any one of the preceding claims.

17. A method for determining a position and/or orientation of at least one levitated transport body (12) having one or more permanent magnets (12 a) relative to a magnetic levitation feed unit (14), the method comprising the steps of:

providing weight signals at a plurality of weight sensor locations (22 a) along the levitation feed unit (14), wherein the weight signals are dependent on gravity, and wherein the gravity is caused by the levitated transport body (12) and acts at least partially on the levitation feed unit (14); and is

Determining the position and/or orientation of the at least one suspended conveying body (12) on the basis of the weight signal.

18. The method of claim 17, further comprising the steps of:

providing magnetic signals at a plurality of magnetic sensor locations along the levitation feed unit (14), wherein the magnetic signals are dependent on a magnetic force, and wherein the magnetic force is induced by the at least one levitated transport body (12);

wherein the position or orientation of the at least one suspended conveying body (12) along the suspended feed unit (14) is determined by means of the weight signal and the magnetic signal.

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