DE3615291A1 - ELECTROMAGNETIC CONVERTER AND DEVICE FOR DETERMINING A RELATIVE SPEED AND / OR A FORM USING SUCH A CONVERTER - Google Patents

Description

PATENTAN WALTSBURO SCHUMANNSTR. 97 D-4OOO DÜSSELDORF 1 Telephone: (0211) 683346 · Fax: (0211) 6790871 ■ Telex: 8586513 cop d

PATENT LAWYERS:
Dipl.-Ing. W. COHAUSZ ■ Dipl.-Ing. R KNAUF Dipl.-Ing. HB COHAUSZ ■ Dipl.-Ipg. D- H. WERNER ■ Dr rer. nat. B. REDIES

Radiodetection Limited May 5, 1986

Western Drive, 46123

Bristol.
BS14 OAZ. / Great Britain

Electromagnetic converter and device for determining a relative speed

ability and / or a shape using such a transducer

The present invention relates to an electromagnetic converter and a device for determining a relative speed and / or a shape using such a transducer. The invention can be used in the detection a rotary movement and / or to determine the position and / or orientation of a body. the

The invention further relates to a remote control device and to devices with remotely controllable mobile elements are provided, for example devices for penetrating the ground or so-called "moles".

Generally speaking, according to the invention, a rotation of a Converter caused to a synchronously changing magnetic field to create. This field is recorded in one or more angular positions. The axis of the field preferably forms

an oblique angle with the axis of rotation, so that the field performs a circular motion around the axis.

The field preferably changes with time, i.e. it is induced by an alternating current, whereby the changing field is detected inductively via a detector. The degree of inductive coupling between the detector and the field is dependent on the angular position of the transducer relative to the detector.

In one embodiment, a rotatable body is rotatably connected to a transducer, which is an elongated ferromagnetic Comprises member extending at an angle to the axis of rotation. An excitation coil can be arranged be that its axis has at least one coaxial to the axis of rotation component, so that the ferromagnetic Element can be induced and magnetized in the longitudinal direction. The axis of the then magnetized by the Element built up field is aligned to the element, but runs at an angle to the axis of rotation. This Field therefore performs a circular movement around the axis of rotation, synchronized with the rotation. The rotating field can be detected. An embodiment of a corresponding detector or receiver comprises a detector coil which is a ferromagnetic May have core. Such a detector coil is preferably arranged to the excitation coil that in there is essentially no direct inductive coupling between them (in the absence of the ferromagnetic Element). The detector is preferably arranged so that the degree of coupling with the field of the transducer during the rotation fluctuates between almost 0 and a maximum value. This excitation coil is preferably operated with alternating current applied so that the induced field of the ferromagnetic element changes, and the resulting,

changing flow is captured.

In a preferred embodiment, the rotation of a shaft with the help of a ferromagnetic element, which is fixed is connected to the shaft, detected an excitation coil magnetically coupled to the element and a detector coil. The excitation coil preferably runs coaxially to the shaft. It is preferably arranged in a stationary manner (alternatively the excitation coil can also rotate together with the shaft, i.e. wound around the ferromagnetic element be. It can then be excited via slip rings). The axis of the detector coil preferably runs parallel to a tangent to the excitation coil and essentially in a radial plane thereof. The detector can also be arranged symmetrically about the axis of rotation, with its own axis parallel to the plane the excitation coil extends. The axes of the ferromagnetic element, the shaft and the excitation coil intersect preferably at about one point. Preferably, the shaft is non-magnetic and non-conductive, at least in the vicinity of the excitation coil and the ferromagnetic element.

When in such a preferred embodiment alternating current is applied to the excitation coil and As the shaft rotates, the fluctuating induced field of the ferromagnetic element creates a changing one Magnetic flux within the detector coil, its mean amplitude during a single rotation of the frond a first maximum, a minimum (essentially 0), a second maximum (opposite a different phase excitation at the first maximum) and a second minimum. The detector coil can thus be on

provide the output signal related to the rotation of the shaft. A variety of detector coils used in Angular distances spaced around the shaft can provide a polyphase output signal from which information about the angular position of the shaft can be derived. In fact it can use a variety of detectors Provide data on the position and orientation of the shaft. In another embodiment, a Body provided with a transducer unit, which is a rotatable Having shaft. The use of the detectors described above makes it possible to determine the location and Determine the orientation of the body.

Embodiments of the invention are shown in FIG Connection with the drawing explained in detail. Show it:

FIG. 1 shows a side view of a device designed according to the invention;

Figure 2 is a front view of this device;

characters

3a to 3d views similar to FIG. 1 for explanation

Figure 4

the functioning;

a diagram of the detector output signal;

characters
5 and 6

Views similar to Figure 1 showing other embodiments;

Figure 7a is a view similar to Figure 2 showing a detector in the form of a toroid;

FIG. 7b shows a side view of the device of FIG. 7a, with the detector in section is shown;

characters
8a and 8b

Views similar to Figures 7a and 7b showing a further embodiment;

Figure 9 is a diagram to explain the

Operation of the embodiment of Figure 8;

Figure 10

Figure 11

Figures 12a and 12b

a vertical section through a penetration device (Mole) according to the invention;

a perspective view of a second embodiment of one according to the invention trained piercing device;

Side and inside views of a toroidal transducer or aerial Axial section;

FIG. 13 shows an axial section through the toroidal transducer of FIG a longitudinal coil is equipped;

Figure 14 is a view similar to Figure 13 showing a modified embodiment;

FIG. 15 shows an axial section through a practical embodiment of a transmission unit for

a piercing device; and

Figure 16 shows a detail of the embodiment of the figure

15 in a different orientation. 5

Figures 1 to 3 show a shaft 10, the rotation of which is to be examined and at least in the one shown Section is not magnetic and designed as an electrical insulator. A bore 12 extends through the axis of rotation at an acute angle. A ferromagnetic element 14 (which is suitably made of ferrite) is mounted symmetrically in the bore so that there are equal distances on each side protrudes from this and thus does not disturb the equilibrium of the shaft 10. A stationary excitation coil 16 is arranged coaxially to the shaft 10 and mounted around this in such a way that its central radial plane is the plane of intersection of the axes the shaft 10 and the element 14 contains. The central opening 18 of the coil 16 is large enough to be free Allow rotation of the shaft 10 and member 14. Lines 20 lead to an alternating current source. A Detector 22 has an elongated coil 24 wound around a ferrite core in the form of a cylindrical rod 26 is. Its axis runs parallel to a tangent to the excitation coil 16 or the shaft 10 and is located in the center plane of the excitation coil 16.

In operation, an alternating current (preferably with a frequency in the range from 1 kHz to 150 kHz) is applied to the Excitation coil 16 placed. During a half cycle, the current induces the ferrite element 14 so that this becomes a bar magnet with a north pole and a south pole at opposite ends. Naturally the poles are reversed in the next half cycle.

The element 14 thus becomes a continuously switching bar magnet. The magnetic field built up by the element 14 has an axis which is aligned with the axis of rotation of the shaft 10, but extends at an angle to this, so that the field executes a circular movement around the shaft 10 at its rotational speed. This field is coupled to the detector 22, the degree of coupling depending on the angular position (the induced bar magnet can also be divided into an axial and a radial component relative to the shaft 10). The radial component forms a fluctuating magnetic field which rotates together with the shaft 10 and is coupled to the detector 22 (the degree of coupling depending on the angular position). As can be seen from Figure 3, the coupling has a maximum when the element 14 is in a plane parallel to the detector 22 (Figures 3a and 3c), and is essentially zero in positions offset by 90 ° (Figures 3b and 3d). The signals induced by the detector coil 24 have an opposite phase (in relation to the excitation signal in the excitation coil 16) in the positions of FIGS. 3a and 3c. The excitation signal 29 and the output signal of the coil 24 are shown in FIG. The solid line 30 and the dashed line 32 show the signal modulation envelopes for one revolution. This section of the envelope has two bulges B, B ¹ and a node N. In the first bulge B, the signal current 31 in the detector is in phase with the excitation signal 29, while it has an opposite phase in the second bulge B '. This phase relationship can be detected and used to carry a phase information

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Output signal, i.e. that represented by line 30 is. This signal is quasi-sinusoidal, the actual shape depending on the angle that the element 14 relative to the shaft 10 assumes. The modulation frequency is based in a simple manner on the speed of rotation of the shaft 10 related. The output of a single detector 22 can thus be an input for a remote one Provide tachometer 39 available, which generates a display showing the speed of rotation.

If further detectors 40a, b (FIG. 2) are arranged in a manner corresponding to the detector 22 at intervals of 120 ° are, the modulation of the signals induced in the three detectors forms a three-phase pattern from which the The angular position of the shaft can be calculated precisely over the full 360 °. Two detectors 90 ° apart lead in a corresponding manner to a two-phase result. Of course, other multiphase systems can also be used in can be generated in a corresponding manner.

The or each detector coil 24 is preferably arranged tangentially to the shaft 10 and in the plane of the excitation coil 16, as shown in Figures 1 to 3. This simplifies the output signal, since it is a direct one Coupling with the excitation coil 16 is avoided. However, other positions can also be used. For example FIG. 5 shows a detector 40c, the center of which is still in the plane of the excitation coil 16, however, its axis runs parallel to the axis of the shaft 10. This leads to an output signal whose size is variable, the phase of which, however, is not variable, the maximum being the 0 position of FIG. 3b is equivalent to. Figure 6 shows a detector 40d, the center of which is on the axis of the shaft 10 and its

Axis runs normal to this. This leads to an output signal where both phase and size are variable.

As explained above, a single detector can be used to determine the speed of rotation of the shaft 10, and a variety of detectors can be used can be used to provide data on their angular position. Furthermore or alternatively, a plurality of Detectors are used to calculate the orientation of the shaft relative to the detectors, if any should be changeable. Therefore, a body can be provided with a transducer unit having a rotatable shaft 10, a ferromagnetic element 14 and an excitation coil 16 in the manner described above.

The field, which is generated in this way and executes a circular movement, can be passed through one or more remotely located detectors are detected. The district. movement of the field means that the modulation depth and the phase properties of a detected signal the orientation of the detector relative to the transducer unit Show. If this unit has a fixed detector (as arranged in Figure 6 and suitably attached to a Housing of the shaft 10 mounted), can by comparing the phase of the output signal of this detector with that of a remotely located detector, their relative orientation can be determined in a simple manner. Angular differences around the axis of rotation (the shaft) correspond to phase shifts.

By using an alternating current of a high frequency, a high degree of variation of the flow can be generated in a detector, so that detection

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36T5291

from standstill to high speeds and beyond is possible over considerable distances. In addition, the inclined position of the induced Magnets that generate a circular motion field, the properties of which allow other types of determination do.

FIGS. 7 and 8 show a device which essentially corresponds to that of the preceding figures, but has a different embodiment of a detector. Instead of the rod-shaped detector elements 26, 40 etc., a detector 41 in the form of a toroid, that is to say an annular detector, is used. As FIG. 7 shows, a toroidal ferromagnetic core 43 is completely occupied by a continuous, equally spaced winding 44. The dash-dotted line L with arrows indicates how the flux induced in the rod 14 is divided into two parallel paths through the toroidal core, so that electromotive forces are generated which generate a maximum voltage at diametrically opposite taps x, x ¹ in alignment with the Create rod 14. By rotating the shaft 10, the voltage at these tapping points is reduced to 0 after a movement of 90 °. A further rotation increases the voltage, but with the opposite phase relative to the frequency of the alternating current applied to the excitation coil 16. The amplitude of the voltage follows a sinusoidal path relative to the angle of rotation (more precisely than in the previous embodiments). Three taps x, y, z, which are arranged at intervals of 120 °, generate three phase (delta) voltages between them.

If four tapping points at intervals of 90 ° at

x, y, χ ¹ and y ^{1 of} the winding 45 are arranged, as shown in Figure 8a, the signal voltages, which ^{are measured at the diametrically opposite tapping points x, x 1} and y, y ', run through sinusoidal curves, which by 90 ° are shifted against each other. Although the measured signals include the AC carrier frequency in coil 16 which is modulated by rod rotation in the manner illustrated in Figure 4, it is more convenient to show these signals after demodulation via conventional electronic techniques (via signal processing means 48), see above that direct current levels are generated whose size changes with the amplitude of the modulation and whose polarity changes with the relative phase of the modulated signal to the supply frequency. This result is shown in FIG. 9 for the construction of FIG. It is evident that the two curves correspond to the sine and cosine of the angle of rotation. Conventional electronic techniques (via signal processing devices 48) can be used to derive analog or digital data representative of the absolute angular position of the shaft.

The device therefore has the same behavior as a conventionally designed brushless resolver, however with a much simpler construction. The conventionally designed resolver has a wound two-phase stator and a wound single-phase rotor and further comprises a rotary converter to the required To provide rotor excitation. This makes a high level of accuracy in the design and Winding required. The device according to the invention is not only simpler and cheaper to manufacture, but is also better suited to miniaturization, since it only has a single stator unit with a toroidal one

wound core and an inner excitation coil as well as a non-wound rotor made of a ferrite rod or an equivalent laminated steel structure. The embodiment of Figure 7 can be a Replace three-phase brushless resolver.

A device for electromagnetic monitoring, Arrangement and tracking of moving objects out of sight is now in connection with FIGS. 10 and 11 are described.

The possibility of using the device to determine the relative orientation of the Rotating shaft and a remotely located detector pointed out. A special application example for this is the electromagnetic measurement of positions and orientations that are not optical or equivalent Facilities can be carried out, i.e. if the object to be measured is underground.

If a transmitter, which includes the rotating transducer and the excitation coil of Figure 1, on a known Point with a known orientation is placed in a receiver, which is typically a coiled Ferrite rod includes, which is attached to the object to be located or guided, with a signal the frequency applied to the excitation coil (reference frequency) induced, however, depending on the degree of Rotation is modulated. The modulation depth relative to the reference frequency signal and the amplitude change with the orientation of the axis of rotation of the transmitter and the rod axis of the receiver in a way that is a makes mathematical analysis and calculation possible. A second transmitter in a different known location

_ -I Q _

is arranged, makes a calculation of the relative orientation of the receiver in a corresponding manner Transmitter possible so that the two results provide a derivation of the actual position of the receiver via enable triangulation. If a simultaneous calculation is to be carried out, different Reference frequencies are used for each transmitter along with suitable filtering of the receiver signals will. Of course, more than two transmitters can also be used to increase the trust level of the Increase calculation result. A corresponding application is shown in FIG. 10 in connection with the simple one monitoring of the rectilinear movement of an earth drilling tool and shown in Figure 11 in connection with the guidance of a steerable version of such a tool.

As can be seen in Figure 10, there is a piercing tool ("Mole") 50 formed so that it traverses a rectilinear path through the illustrated Arrow is indicated. The tool is driven via a hose 55 with the aid of a fluid. For example, it can be the laying of a pipe or a cable through the ground act on a road without affecting the road surface or the traffic flowing on it should be drawn. However, the tool may be due to variations in soil consistency or deviate from the rectilinear path as a result of encountering unexpected obstacles, resulting in undesirable Consequences if such a deviation remains undetected.

When a receiver 51 is attached to the "mole" and the transmission unit 52 mounted in an output shaft with its shaft in precise alignment with the The hole to be drilled should be the signal that should be detected by the receiver and transmitted over the cable 60 along the feeder of the pneumatic or hydraulic working medium for the tool is returned, only the Contain reference frequency and have a decreasing amplitude with increasing distance, but one Have zero modulation as long as the tool and the receiver axis coincide. When the tool deviates from this straight path by a divergence angle d, the signal from the receiver 51 with the Modulated rotation frequency. The modulation depth increases with d. The phase of this modulation varies with the Angle p, which is the deviation relative to the required hole axis. If the The transmitter is provided with a detector reference coil 53 of a known orientation about the axis of rotation by comparing the phase of the signal 51 with the phase of the signal 53 (via signal processing devices 62) the angle ρ can be determined. This system is therefore able to respond to a predetermined one To draw attention to the degree of divergence going beyond the limit and, moreover, the direction of this divergence to display.

As Figure 11 shows, the penetration tool is designed so that it can be controlled remotely. It has two rod-shaped receivers 51, 54. These receivers are elongated coils on ferromagnetic cores. They are preferred for ease of calculation arranged perpendicular to each other, with a

Core 51 is precisely aligned with the body of the tool. A plurality of spaced apart transmitters can be provided. In the illustrated embodiment, three transmitters (T-, T ₂ and T ₃ ) are used. Each transmitter has a known position, tilt, and orientation that have been established through normal surveying techniques. The elongated receiver 51 receives a corresponding signal from each transmitter which carries a modulation related to the relative position and orientation of a corresponding transmitter. By analyzing the two signals (via a computer 70), the vectors V., V ₂ and V ₃ , which embody the position relative to the corresponding transmitters, can then be calculated. The exact position of the tool can thus be calculated and compared with the required path, and a correction signal can be sent to the remote control system 64 if this should be necessary (the transmitters can be switched on one after the other or at the same time if they have different frequencies and / or Use rotation values).

However, in order for the tax system to work properly, it is It is important to know any changes in the roll axis of the tool. If the tool is with Ribs 64 is provided, for example to enable steering to the left or right, a rolling of the Tool by 90 ° cause these ribs to steer up or down instead.

To obtain this information, a second receiver 54 is required, the axis of which is normal to Axis of the longitudinal element 51 runs. When the axis

54 extends horizontally, for example in the starting position of the tool, has any of the tool received modulated signal has a corresponding phase reference as a signal received by another receiver 56 is received, which is arranged horizontally at a selected location. If the tool in the course of its Traversal rolls, the phase difference between the signals from 54 and 66 to the Roll angle related, the steering system is set so that this corrects via suitable devices will.

The exemplary embodiments described and illustrated below for locating and tracking systems are based for reasons of expediency on the concept of fixed transmitters and moving receivers. It goes without saying however, that the conditions can also be reversed, i.e. the transmitter attached to the moving object and the Receiver can be installed in known locations and in known locations. In this case can be a single Transmission frequency is sufficient for a simultaneous calculation of the position vectors of various receivers be.

Such penetration or piercing tools and corresponding objects can, for example, through Compressed air, driven from a remote location, so that the attached electromagnetic Elements must be designed so that the corresponding line for the work equipment, for example a fluid tube through which it may extend. In any case, cables can be provided to Work equipment and / or the corresponding data

wear. That means that usually only a ring-shaped Volume is available for transmission or reception of the corresponding conditions.

If it is desired to provide separate information about the position and the rolling process, then two separate receive or transmit channels required. These can be provided by two coiled aerials fixed at right angles to each other, as shown in FIG. This embodiment however, has two limitations:

(a) She is not readily eligible for the passage of one Fluid line etc. suitable;

(b) the ferromagnetic rods that are in close proximity are arranged to each other, affect each other to a certain extent, so that that of the other element sensed or generated field is locally deformed.

In FIGS. 12-14, aerial or converter units are shown with which these restrictions are eliminated can be. In these units, the active material is arranged in a ring. Essentially the entire common ferromagnetic core material can be used within each sense winding, with one such above-mentioned local influencing and field deformation is avoided or correspondingly reduced.

If one begins with the requirements for the roilage detection or transmission, FIG. 12 shows an aerial 78 which like all radio antennas for sending or receiving

Signals can be used. It comprises a toroid of ferromagnetic material 80, which is usually around a helically wound steel strip of suitable thickness with appropriate magnetic Properties for the respective application purpose, on which there is a toroidal winding 82 which ends at a and b. This in turn comprises two nominally equal sections in a row, each covering 180 ° (one on each side of the diameter AB in Figure 12a) and are arranged in such a way that their electromotive forces add up when they change to an external one Magnetic field in the vertical direction, which is indicated by the dashed line 84 in Figure 12a, exposed will. It goes without saying that the resulting flux in the core runs through each half of the toroidal core divides; a corresponding effect arises when this element is used as a transmitter. Excitation terminals a, b with an alternating or direct voltage form at points A and B in one of the historical gram winding anchors corresponding magnetic poles, so that a field of orientation A-B is generated in the space. If at the excitation alternating current is used, the field also changes. This can emf signals in a receiving aerial induce appropriate orientation (not shown).

The aerial 78 (antenna) thus serves as a transmitter. In this mode of operation, points C and D are magnetically neutral. It will be understood that the aerial 78 can also be used as a receiver. Figures 7 and 8 show an aerial 43, 44, which fulfills this function. An outer field with a horizontal orientation C-D leads to an output signal from 0 to terminals a and b. The signal output therefore changes approximately sinusoidally with the orientation of the element to the outer alternating field, with a maximum for the A-B direction and a minimum for the C-D direction is obtained. The phase of the signal output also changes

relative to the field source, since the rotation of the element and the field relative to one another causes the signal output passes through the zero state. The signal amplitude and signal phase can therefore be designed appropriately electronic systems are processed to provide information about the angular orientations of the receiver and the external field source available, as already described in connection with FIGS. 7 to 9 has been. A suitable transmitter of this configuration causes the orientation of its external field changes with the roll angle, which is then detected and interpreted by suitable remote receiver systems can be.

The embodiment shown in FIG. 13 has the same features for axial position detection or transmission toroidal element 78, which is further provided with a simple longitudinal coil 86 which is wound around a suitable shaped element 88, which is the toroidal winding surrounds. It is understood that when used as a receiver, an external alternating current field in the horizontal or in the axial direction, as indicated by the dashed line 90, along in the ferromagnetic core of the toroid is concentrated and an electromotive force in the axial winding 86, but not in the toroidal winding 82 is generated. The induced electromotive force has a maximum when the field direction and the coil axis coincide. As the direction of the external field moves away from this axis, the falls electromotive force decreases to zero when both are perpendicular to each other. Another relative rotation increases the electromotive force, but in opposite phase relative to the AC power source.

When used as a transmitter, an excitation of the steering coil 86 at the terminals c and d causes one of the coil axis outgoing and oriented field generated. The signal from this field can be located via appropriate remote locations Receiver systems are processed to 'position information about the relative position and the distance between transmitter and receiver.

Although the principle of the invention in conjunction with a full toroidal core has been explained, the same advantages can be obtained by using divided the toroidal core and windings into two halves, as shown in FIG. This quasi-toroidal core is divided into two halves 80a, 80b with corresponding winding sections 82a, 82b. By exposing the ends of the nuclei at points A and B, development or palpation becomes external Fields in A-B direction improved. Furthermore, the most effective section of the toroidal winding is the middle one Section, so it should be more efficient for material use and operation, only short middle ones To use windings 82a and 82b, which in turn are connected in series. The removal of ferromagnetic Material at the exposed points A and B has only a slight weakening effect on the coupling to the Longitudinal winding 86, however, the overall cross-section of the structure becomes oval rather than circular.

A simpler and cheaper way to produce a modified one toroidal core with improved ability to act as a Swei-Pol structure in A-B direction in taking a simple tubular core (like core 80 in Figures 12 and 13) and two diametrically drill opposing rows of diametrically extending holes 90, 92 (Figure 12b) the length of the core

(at locations A and B in Figure 12). (Of course then no windings 82 present in the areas of the holes 90, 92).

From the foregoing it is clear that the entire ferromagnetic content of the toroidal core is applied to both Sets of windings are coupled so that in this way interference problems are kept to a minimum which are present in separately wound rods made of ferrite or another suitable material are. It is also clear that therein a free cylindrical space for the passage of pipes or other Cables is created.

Figures 15 and 16 show a presently preferred embodiment of a transmitter 100 for a circular motion Executing field used to monitor a penetration device is suitable, as shown in Figures 10 or 11. The transmitter has a converter unit 102, a non-metallic shaft 104, and means 106 for rotating the shaft 104.

The converter unit 102 is basically the same as that used in connection with FIGS to 9 has been described. However, it was preferred to have the ferromagnetic element 108 here as a laminated steel core to train, as such can transmit higher energy. For the sake of simple construction, this is Element 108 is formed from two parallel sections, each consisting of a stack of rectangular layers. To assemble these sections, the shaft 104 has two angled slots 110 (see FIG. 16) in a central section 112. The two sections of the element 108 are by means of clamping bolts 114, which are

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through openings in the end regions of the element 108 and engaged with nuts to clamp the shaft 104 together.

The excitation coil 116 wound around a coil element 118 is designed so that it surrounds the element 108 closely. It is therefore, when assembling the device, it is necessary to mount the element 108 after the coil 116. The two Sections can easily be inserted into their respective slots 110 and then over bolts 114 together get connected. In order to balance the element 108 around the rotor 104, its position is variable Linkage parts that extend from bolts 114 to shaft 104 are finely adjustable. Every linkage part has a non-metallic tie rod 120 extending between the portions of the member 108, and a elongated non-metallic pin 122, which extends from the pull rod 120 through the shaft 104 in an adjustable Measure extends. Each peg 122 carries a non-metallic counterweight 124 to thereby reduce the weight of the element 108 to balance forces generated during the rotation of the shaft 104.

The rotating device 106 has a motor 126, which with the shaft 104 is coupled. The shaft is in bearings 128

mounted, which are mounted in non-metallic end plates 130, between which tubular housing sections 132, 134 are mounted, which are in engagement with the bobbin holder 118 and position it. 30th

The receivers 136 for generating a reference signal are designed as longitudinal coils which are wound around ferrite rods and are mounted in radial cavities in an end plate 130.

The electronic systems used to collect the data from the circular motion fields of the transmitters of the receiver signals have not been described above, as a large number of Different techniques and circuits can be used by a person skilled in the art for this purpose and in guidance systems including radio transmissions between the guided object and the receiving or control stations finds.

Naturally, the devices and methods described above (as well as parts thereof) can be used in different Situations apply and are used for different purposes than those described above.

Claims (1)

COHAUSZ & FLORACK ori-on, 3b I Ό23 ι PATENT AGENCY OFFICE
SCHUMANNSTR. 97 D-4OOO DÜSSELDORF 1 Telephone: (0211) 683346 Fax: (0211) 6790871 ■ Telex: 8586513 cop d PATENT LAWYERS:
Dipl.-Ing. W. COHAJSZ Dipl.-Ing. R. KNAUF ■ Dipl.-Igg. HB COHAUSZ Dipl.-Ing. DH WERNER Dr. rer. nat. B. REDIES May 5, 1986 46123 Claims 1. Converter for generating a variable magnetic field, marked by: A rotatable shaft (10, 104 \ having an axis of rotation; an elongated ferromagnetic element (14, 108) mounted on the shaft (10, 104) so that it lies beneath extends at an acute angle to its axis of rotation; and an excitation coil (16, 116) so arranged with respect to the elongated ferromagnetic element (14, 108), that through the passage of a current through the coil (16, 116) the elongated ferromagnetic element (14, 108) is induced so that it is magnetized in the longitudinal direction with a direction of magnetization which is determined by the Direction of the current in the coil (16, 116) is dependent, so that a rotation of the shaft (10, 104) a Circular motion executing magnetic field can be generated, while an alternating current through the coil (16, 116) flows. 2. Converter according to claim 1, characterized in that that the excitation coil (16, 116) is substantially coaxial with the axis of rotation of the rotatable shaft (10, 104) is arranged. 3. Converter / receiver unit with one converter after one of the preceding claims, characterized in that that it has at least one receiver (22, 40a, b, 40c, d, 41, 51, 53, 54, 78, 136) which is able to generate an electrical signal when exposed to a varying magnetic field. 4. converter / receiver unit according to claim 3, characterized marked is that at least one receiver has a detector coil (22, 40a, 40b) and so relative to the excitation coil (16) is arranged so that there is essentially no direct inductive coupling between them. 5. converter / receiver unit according to claim 3, characterized gekenn ze ichnet that it has a plurality of such receivers (22, 40a, 40b), which in corresponding different angular positions are arranged relative to the axis of rotation of the shaft. 6. converter / receiver unit according to claim 3, characterized in that at least one receiver a toroidal coil (41, 78) preferably mounted substantially coaxial with the axis of rotation of the shaft is. 7. converter / receiver unit according to one of claims 3 to 6, characterized in that it further comprises a signal processing device (39, 48, 62, 70) which is connected to at least one receiver (22, 40a, b, 44, 51, 53 , 54, 56) is coupled to receive the electrical signal therefrom and is able to derive from the signal data relating to the rotation of the shaft (10, 104) and to display this data.
10 8. converter / receiver unit according to one of claims 3 to 7, characterized in that the receiver has a toroidal coil (41, 78) which has a plurality of tapping points in different angular positions of the coil, so that an electrical Multiphase signal can be derived. 9. Device for monitoring the position and orientation of a body, characterized by a transducer / receiver unit according to one of the claims 3 to 8, a transmitting device and an Eittpfangeneinheit which are displaceable relative to one another, wherein either the transmitting unit or the receiving unit can be mounted on the body. 10. Apparatus according to claim 9, characterized in that the transmitting unit has a reference receiver (4Od, 53, 136), which is fixed relative to the transducer and is able to generate an electrical signal to produce when it is exposed to a variable magnetic field due to the transducer, and that the device further comprises a data processing device (62, 70) which is connected to the reference receiver and at least one receiver (51, 54) of the receiving unit is coupled in order to receive corresponding signals therefrom received, wherein the data processing device is able to compare these signals. 11. Apparatus according to claim 9 or 10, characterized in that g e that the receiving unit (51, 54) can be mounted on the body (50) and that the transmitting unit at least two transducers (T ,, T_, T ^) connected to each other having spaced locations. 12. Device according to one of claims 9 to 11, d a characterized in that the receiving unit comprises two receivers (51, 54), each one have magnetic axis, and that the axes of the two receivers (51, 54) in substantially one another perpendicular planes. 13. Device according to one of claims 9 to 12, as through characterized in that the receiving unit has a toroidal or quasi-toroidal shaped wound coil (41, 78) comprises. 14. Device: "according to claim 15, characterized in that g e characterizing net that the receiving unit is the toroidal or quasi-toroidal wound coil (80, 82a, b) and a longitudinally wound coil (86) and that the coils are arranged coaxially are. 15. Device for monitoring the position and orientation of a body, characterized in that it has a transmitting unit and a receiving unit, which are displaceable relative to one another that the Sfeideeinheit or the receiving unit on the body is mountable and that the transmitter unit at least comprises a coil unit which is toroidal or quasitoroidal wound coil (80, 82a, b) and a longitudinally wound coil, which coaxially are arranged.