JPS6217616A - Electromagnetic transducer assembly and means for measuring relative speed and/or arrangement by using said assembly - Google Patents

Abstract

(57) [Summary] This bulletin contains application data before electronic filing, so abstract data is not recorded.

Description

DETAILED DESCRIPTION OF THE INVENTION Field of the Invention The present invention relates to an electronic transducer assembly and means for measuring relative velocity and/or position using the assembly. It can be used to measure position and/or orientation. In another aspect, the invention provides a remote control device and a remote; IJIi211 capable mobile element;
For example, it relates to an assembly with a soil boring machine or tunnel boring machine (■ole).

[Disclosure of the invention]

Broadly, in a first aspect, the invention preferably includes rotating a transducer to produce a sinusoidally varying magnetic field and detecting the magnetic field at one or more angular positions. , the magnetic field has an axis that defines an approximately acute angle to the axis of rotation, so that the magnetic field pivots about the axis.

Preferably, the magnetic field changes over time, for example induced by an alternating current, and the changing magnetic field is inductively captured by the detector. Generally, the degree of inductive coupling between the detector and the magnetic field is a function of the angular position of the transducer relative to the detector.

In one form, a transducer is fixed to the rotatable object, the transducer comprising an elongate ferromagnetic element extending at an angle to the axis of rotation, and the axis of the excitation coil being magnetized at least longitudinally. A component is provided coaxial with the axis of rotation such that the ferromagnetic element to be processed can be guided. The magnetic field created by the &PLed ferromagnetic element has an axis aligned with the ferromagnetic element but at an angle to the axis of rotation. therefore,
This magnetic field rotates around the rotation axis in synchronization with the rotation. j
The ti magnetic field can be detected. One form of detector or receiver includes a detector coil with a ferromagnetic core. Such a detector coil is preferably arranged relative to said excitation coil such that (in the absence of ferromagnetic elements) there is substantially no direct inductive coupling between the detector coil and said excitation coil. /I will be done. Preferably, the detector is arranged such that the degree of coupling to the transducer's magnetic field varies from substantially zero to a maximum during rotation. Preferably, an alternating current is supplied to the excitation coil such that the induced magnetic field of the ferromagnetic element changes and the final changing magnetic flux is detected.

In one preferred arrangement, the rotation of the shaft is
Detection is achieved by a ferromagnetic element fixed to the shaft, an excitation coil magnetically connected to the ferromagnetic element, and a detector coil. Preferably the excitation coil is arranged coaxially with the shaft. Preferably the excitation coil is fixed; alternatively, the excitation coil is wound for example on a ferromagnetic element and rotates with the shaft. This excitation coil can be excited via a current collector ring. Preferably, the axis of the detector coil is in a direction parallel to a tangent to the excitation coil and substantially in the radial plane of the excitation coil. In one variant, the detector is symmetrical about the axis of rotation, the axis being parallel to the plane of the excitation coil. Preferably, the axes of the ferromagnetic element, the shaft and the excitation coil intersect at approximately one point.

Preferably, the shaft is non-magnetic and non-conducting at least in the vicinity of the excitation coil and the ferromagnetic element.

In such a preferred arrangement, when the excitation coil is supplied with alternating current and the shaft rotates, the fluctuating induced magnetic field of the ferromagnetic element produces a varying magnetic flux inside the detector coil, whose central amplitude is a first maximum value, a first minimum value (substantially zero), and a second maximum value (different in phase from the first maximum value with respect to the excitation magnetic field) during one rotation of the shaft. , passes through the second minimum value. The detector coil can therefore provide an output signal relating to the rotation of the shaft. A plurality of detector coils angularly distributed around the shaft can provide a polyphase output from which information about the angular position of the shaft can be calculated. In fact, multiple detectors provide data about the position and orientation of the shaft. In other types of arrangements, the object is provided with a transmitter assembly that includes a rotating shaft. The use of the detectors described above makes it possible to measure the position and orientation of objects.

Some embodiments of the invention will now be described in more detail with reference to the accompanying drawings.

〔Example〕

As shown in FIGS. 1 to 3, the shaft lO whose rotation is to be investigated is non-magnetic and electrically insulating at least in the illustrated portion. The hole 12 passes through the rotation axis at an acute angle. Five ferromagnetic elements 14, preferably made of ferrite, are fixed symmetrically within the hole 12 and protrude by the same amount on both sides so as not to affect the balance of the shaft IO. A fixed excitation coil 16 is disposed coaxially around the shaft IO, in its central radial plane the axes of the shaft 10 and the ferromagnetic element 14 intersect. The central opening 18 of the coil 16 is connected to the shaft 10 and the ferromagnetic element 1.
Conductor lO large enough to allow free rotation of 4
is connected to the AC servo motor. Detector 22 comprises an elongated coil 24 wound around a ferrite core in the form of a cylindrical rond 26. The axis of the detector 22 is parallel to the tangent to the excitation coil 16 or the shaft IO and lies in the central plane of the excitation coil 16.

In operation, an alternating current (preferably at a frequency in the range of 1 kHz to 150 kHz) is supplied to the excitation coil 16. During the half cycle, the induction of current causes the ferromagnetic element 14 to become a bar magnet, with north and south poles at its ends. Of course, in the next half cycle the poles are reversed. Therefore, the ferromagnetic element 14 becomes a bar magnet that repeats reversals.0 Ferromagnetic element 1
The axis of the magnetic field provided by 4 is aligned with the ferromagnetic element 14, but at an angle to the axis of rotation of the shaft IO, so that the field pivots around the shaft IO at its rotational speed. This magnetic field is coupled to the detector 22, the degree of coupling varying with angular position. (From another perspective,
The guide bar magnet can be broken down into an axial component and a radial component with respect to the shaft 10. The radial component provides a varying magnetic field. This varying magnetic field rotates with shaft 10 and is also coupled to detector 22 . Its degree of coupling changes with angular position. Referring to FIG. 3, coupling occurs when the ferromagnetic portion ff114 is in a plane parallel to the detector 22 (
3a and 3C), and at a position of 90° to the plane (Figs. 3b and 3d).
Figure) becomes essentially zero. In fact, the signal induced in the detector coil 24 is in opposite phase 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 from the coil 24 are Fourth
As shown in the figure. The solid line 30 and the dashed line 32 show the modulation envelope of the signal during one revolution, this envelope section having two bulges B, B' and a node N. In the first bulge B, the signal current 31 in the detector is in phase with the excitation signal 29, and in the second bulge B' it is in opposite phase. This phase relationship can be detected and used to generate an output signal that provides phase information as shown, for example, by line 30. This signal is a quasi-sinusoidal waveform whose shape depends on the angle of the ferromagnetic member 14 with respect to the shaft 10 and whose modulation frequency is Q! It is purely related to the rotational speed of the shaft 10. It will be readily seen that the output from the single detector 22 provides the input for a remote tachometer 39 which provides a display indication of rotational speed, if separate detectors 40a, 40b (FIG. 2) are used. 1 as well as the detector 22
If spaced 20 degrees apart, the modulation of the signals induced in the three detectors would constitute a three-phase pattern.

From this, the angular position of the shaft can be calculated accurately over the entire 360°. A pair of detectors separated by 90° would give a two-phase result as well, and of course other polyphase systems could be created R4Q.

As shown in FIGS. 1-3, the single or each detector coil 24 is preferably tangential to the shaft 10 and in the plane of the excitation coil 16 because: This arrangement prevents direct coupling to the excitation coil 16 and simplifies the output signal. However, other arrangement structures may be adopted. For example, the center of the detection W40c shown in FIG.
, but the axis of the detection F540c is within the shaft 10
is parallel to the axis of This arrangement provides an output that varies in magnitude but does not vary in phase, the maximum output will correspond to the null position of FIG. 3b, with the center of the detector 40d shown in FIG. Detection S 40
The axis of d is perpendicular to the axis of shaft 10; this arrangement will provide an output that varies in both phase and magnitude.

As already mentioned, a skewer detector can be used to measure the rotational speed of the shaft 10, and a plurality of detectors can be used to provide data regarding its angular position. Additionally or alternatively, multiple detectors can be used to calculate the orientation of the shaft relative to the detectors if the orientation changes. Therefore, as described above, the rotatable shaft IO and the ferromagnetic member 14
A transducer assembly comprising an excitation coil 16 and an excitation coil 16 is mounted on the object. The rotating magnetic field created by this is 1
It may be detected at predetermined locations by one or more remote detectors. The swirling motion of the magnetic field means that the depth and phase characteristics of the modulation of the detected signal are indicative of the orientation of the detector relative to the transducer assembly. If the transducer assembly includes a fixed detector suitably mounted on the housing of shaft 10, arranged as shown in FIG. 6, for example, the phase of the detector output and the output phase of the remote detector are By comparing these, their relative orientations can be easily determined.

The angular difference around the axis of rotation of the shaft corresponds to the phase shift.

The use of high frequency alternating current increases the rate of change of magnetic flux produced within the detector, so that detection is possible over considerable intervals from standstill to high speed.

Moreover, the strain in the induction magnet creates a rotating magnetic field, a property of which allows another form of measurement.

Figures 7 and 8 are the illustrated embodiments described above! ! ! Although the device shown in FIG.

As shown in FIG. 7, the toroidal ferromagnetic core 43 is completely filled with continuous, evenly spaced windings 44. As shown in FIG. The dash-dotted line with an arrow indicates that the magnetic flux guided into the rod 14 is divided into two parallel paths passing through the donut-shaped core and induces an electromotive force. aligned diametric leader lines x,
Develop a maximum voltage at x'. When the shaft IO rotates, the voltage decreases, and when the shaft IO rotates 90 degrees, the voltage at these lead wires becomes zero. The voltage increases with further rotation, but
The direction of the phase is opposite to the frequency of the alternating current supplied to the excitation coil 16. The amplitude of the voltage becomes more precisely sinusoidal as the angle of rotation changes than in the embodiment described above. Three lead wires spaced 120" apart at x, y, z locations will produce a three-phase (delta) voltage between them.

As shown in Figure 8a, the four lead wires are connected to the inside of the winding.
yl xZ When formed at 90° intervals at yl, diametrical leader lines x, x' and y, y'
The signal voltages measured at points will be sinusoidal curves offset from each other by 90°.

The measured signal contains an alternating stray frequency induced in the coil 16 by the rotation of the rod shown in FIG. This result is illustrated in FIG. 9 with the configuration of FIG. 8, which preferably produces a DC level that varies in amplitude and polarity with the relative phase of the modulating signal with respect to the supply frequency. It will be clear that the two curves correspond to the sine and cosine of the rotation angle. Conventional electronic techniques can be applied thereto (by processing means 48) to obtain analog or digital data corresponding to the absolute angular position of the shaft.

The device therefore functions like a conventional brushless resolver but is of very simple construction.

A conventional resolver has a wire-wound two-phase stator and a one-phase wire-wound rotor, and also incorporates a rotating transformer that excites the rotor. These require precise construction and S-wires.

The device according to the invention is not only simple and inexpensive to manufacture, but also consists of a single stator assembly of a donut-wound core and an internal excitation coil and a ferrite core or equivalent laminated steel construction. Since it has only children, it can be made smaller. It will be clear that the structure of Figure 7 can be substituted for a three phase brushless sink 0.11 machine.

Next, an apparatus for electromagnetic surveying of the placement and movement of invisible moving objects will be described with reference to FIGS. 10 and 11.

The possibility of using the device to measure the relative orientation of a rotating shaft and a remote detector has already been mentioned. This special embodiment is effective for electromagnetic surveying of relative position and orientation, which cannot be measured by optical means or the like, for example when the surveyed object is hidden underground. If the transmitting element with the excitation coil and rotating transducer of FIG. 1 is provided at a known location and orientation, it is attached to the object to be placed or moved! Uke 3 with typical linear ferrite rondo
A signal is induced in the element at the frequency supplied to the excitation coil (reference frequency), but that signal will be modulated according to the rotational speed; the depth and amplitude of the modulation relative to the reference frequency signal will depend on the rotation of the transmitter. A second transmitter located at another known location that varies with the relative orientation of the axis and the receiver's Rondo axis, the changes of which may be amenable to mathematical or computer analysis, may similarly It is possible that the relative displacement of the receiver with respect to is computer analyzed, so that the results of the two calculations allow the position of the receiver to be calculated by the triangular 1j FI quantity. If simultaneous computer analysis is required, the receiver signals can be thoroughly filtered and different reference frequencies for each transmitter can be used. Of course, more than two transmitters can be used to increase the reliability of the computer analysis results. A general example for simple monitoring of the linear motion of a soil drilling tool is shown in FIG. 10, and an overview of a steerable soil drilling tool is shown in FIG.

In Figure 10, a drilling tool (tunnel excavator) 50 is designed to follow a straight path indicated by an arrow and is driven by fluid power via a hose 55. It would be possible for pipes or cables to be inserted through the earth beneath roads without disturbing the soil, however changes in soil hardness or encountering unexpected obstacles may cause tunnel excavators to This can cause the vehicle to deviate from a straight line, leading to undesirable results if undetected.

If the tunnel boring machine is fixed to the receiving element 51
and if the transmitter assembly 52 located within the drilling start hole is provided with a shaft that is precisely aligned with the hole to be drilled, the transmitter assembly 52 is detected by the receiving element and transmits air or liquid to the tunnel boring machine. Cable 60 along the power supply
The signal fed back by should have only a reference frequency whose amplitude attenuates as the distance increases, but
As long as the tunnel excavator and receiver axes are aligned, there is zero modulation. If the tunnel boring machine moves away from this straight path by a divergence angle d, the frequency of the signal from the receiving element 51 will be modulated, the depth of modulation will increase by d, the phase of this modulation varies by an angle p, which is the required direction of deflection about the axis of the hole. If the transmitter is provided with a detector reference coil 53 of known orientation around the axis of rotation, the comparison of the phase of the signal 53 with the phase of the signal 51 by the signal processing means 62 facilitates the measurement of the angle p. Therefore, this system makes it possible to examine divergence angles that exceed specified limits and to indicate the direction of divergence.

Referring to FIG. 11, the tunneling F11 aircraft is designed and constructed for incorporation into a remote power control system. This tunnel excavator has a pair of rondo type receiving elements 51.
I am doing 54. These receiving elements are generally elongated coils on a ferromagnetic core.

To facilitate calculation, these receiving elements are preferably at right angles to each other, one of them (51) being exactly aligned with the body of the tunneling machine. There are multiple spaced apart transmitters.

The illustrated embodiment has three feeders (T+, T2, T3).
are using. Each of the transmitters is placed at a precisely known position, tilt, and orientation by conventional T-measurement techniques. A longitudinal receiving element 51 receives a respective signal from each transmitter, the signals providing modulation with respect to the relative attitude and orientation of each transmitter.

Analysis of the two signals by computer 70 shows that vectors Vl, V2, v3 representing the digit 1 for each transmitter are fJ
allow to be calculated. Therefore, the exact position of the tunnel boring machine is calculated and compared to the required trajectory, and corrective signals are provided to the remote tiht system 64 if necessary. (The transmitters can be energized sequentially or simultaneously if they use different frequencies and/or rotational speeds.

) However, in order for the steering system to work correctly, it is important to know the changes in the rolling axis of the tunnel boring machine. If the tunnel excavator is provided with fins 64 for left or right maneuvers, for example, a 90° roll of the tunnel excavator will cause the fins 64 to perform an amplifier down switching maneuver. Become.

To provide this information a second receiving element 54 is required, the axis of which is perpendicular to the axis of the longitudinal element 51. If the axis of the receiving element 54 is horizontal in the operating position of the tonsure excavator, for example, the modulated signal received by this receiving element 54 is fixed horizontally at the selected position (by the receiving! element 66). If the tunnel boring machine rolls during movement, the receiving element 54°6 will have a similar phase to the received signal.
The phase difference of the signals from 6 will be related to the roll angle, and the steering system will be adjusted by appropriate means to correct the roll.

The embodiments of the above-mentioned fixed and mobile systems are based on the idea of a fixed transmitter and a mobile receiver.

replace those relationships and attach the transmitter to the moving object,
It will be clear that the receiving elements could be mounted at precisely known positions and poses, in which case a single transmitter system would be required to compute the position vectors from several receiving stations simultaneously. It is enough.

Since tunnel boring machines and similar moving objects are remotely powered, for example by compressed air, the attached electromagnetic elements need to have a configuration that allows a working line, such as a fluid power connection hose, to penetrate therethrough. In either case, cables are used that carry power and/or data. The ring typically passes through a transmitter or receiver.

(If it is desired to provide separate information about ff?il and rolling, two separate receivers or transmitters are required. These are two separate receivers or transmitters fixed at right angles to each other as in FIG. Although it can be provided by a wire-wound antenna, this arrangement has two limitations.

tJll It is not possible to easily provide passageways such as fluid flow lines through it.

(bl) Ferromagnetic ronds that are in close contact with each other have a certain amount of interaction and tend to give local distortions of the magnetic field.

FIGS. 12-14 show antenna or transmitter assemblies that can overcome the two limitations listed in F. These use an annular shape of material.

Virtually all of the conventional ferromagnetic core material inside each sense winding can be used, thus preventing or ameliorating such local interactions and field distortions.

Starting with a description of the rolling attitude sensing or transmitting device, FIG. 12 shows an antenna 78 that, like all wireless antennas, can be used for transmitting or receiving signals. The antenna 78 includes a donut-shaped ferromagnetic member 80, typically a helically wound piece of steel of suitable thickness and magnetic properties. A donut-shaped winding 82 is provided on this magnetic member and terminates at locations a and b. The antenna comprises a series of two nominally equal sections (on each side of diameter AB in Fig. 12a) covering 180°, these sections having a vertical external axis indicated by dashed line 84 in Fig. 12a. Arrange them so that their emf is additive when subjected to an alternating magnetic field. The magnetic flux within the core is split and passes through each half of the toroidal core, and a similar result would occur if this element were used as a transmitter. When terminals a and b are energized with DC or AC voltage, magnetic poles reside at points A and B in a manner analogous to the historical Gram-ring (Gra+u+e-ring) armatia, with a spacing in the A-B direction. A magnetic field is generated across them. When alternating current is used for excitation, the magnetic field is also alternating current. Thereby, an electromotive force signal (not shown) in an appropriate direction can be induced into the receiving antenna.

Therefore, in this embodiment, where antenna 78 serves as a transmitter, points C, D are magnetically neutral. antenna 7
It will be equally clear that 8 can be used as a receiver; in fact, FIGS. 7 and 8 show antennas 43, 44 serving such a role.

An external magnetic field in the horizontal direction C-D produces a zero output at terminals a, b. Therefore, the signal output changes to a quasi-sinusoidal waveform with the relative orientation of the nine elements to the external alternating magnetic field, and A-
It is maximum in the B direction and minimum in the CD direction. The phase of the output also changes with respect to the magnetic field source during rotation of t'J, and the magnetic fields relative to each other will cause the output to pass through at zero. Therefore, the amplitude and phase of the signal can be processed by a suitably designed electronic system to provide an external magnetic field source and receiver f8, as already described with reference to FIGS. 7-9.
Gives information about the relative angular orientation of the element.

Similarly, this form of transmitting element causes the orientation of its external magnetic field to vary with the rolling angle, which orientation can be sensed and interpreted by a suitable remote receiving system.

For sensing or transmitting axial position, the embodiment of FIG. 13 shows a similar donut-shaped element 78, which
8 further comprises a simple longitudinal coil 86 wound on a continuous profile 88 surrounding the toroidal winding.

A horizontal or axial external alternating magnetic field, as shown by dashed line 90, in the path to the receiver is concentrated within the ferromagnetic core along the donut shape and induces an emf in the axial winding 86, but the donut No electromotive force is induced in the type winding 82, and the induced electromotive force is at its maximum when the direction of the magnetic field coincides with the axis of the coil. As the direction of the external magnetic field moves away from this axis, the emf decreases and becomes zero when the direction of the magnetic field and the axis of the coil are at right angles. Further relative rotation increases the emf, but in an opposite phase direction with respect to the alternating magnetic field source.

In application to the transmitter, energizing the longitudinal coil 86 at terminals c, d produces a magnetic field directed towards the axis of the coil, from which the signal is processed by a suitable remote receiving system to the transmitter and receiver. Position information about the aircraft's relative attitude and sorting is collected.

Although the principle has been described using a complete toroidal core, similar beneficial effects can be obtained by separating the toroidal core and windings into two halves, as shown in FIG. The donut-shaped core consists of two halves 80a, 80b, each of which is provided with a winding portion 82a, 82b. Place the core end in position A.

The B'"c exposure enhances the generation or sensing of external magnetic fields in the A-B direction. Furthermore, the most effective location of the toroidal winding is in the center, resulting in improved material usage and performance. a short central winding 82a connected in series at points,
It will be found that it is more efficient to provide only 82b, the exposed portion Δ.

Removal of the ferromagnetic material at B results in a small longitudinal winding 86
The overall cross-section of the structure is more oval than circular, which has the effect of reducing the coupling to.

8-A method for easily and inexpensively manufacturing a deformed donut-shaped core that acts strongly as a bipolar structure in the B-axis direction is described in the 12th
Using a simple cylindrical core, such as the core 80 shown in FIGS. The method is to drill through holes along A and B). (Of course, the winding 82 is not provided in the region of the hole 90°92.) As is clear from the above description, the entire ferromagnetic material of the donut-shaped core is joined to two sets of wires, and therefore the ferrite or other suitable material to minimize interaction problems that arise with separate winding antenna ronds. It will also be clear that this structure has a cylindrical space inside for passing piping or other cables.

FIGS. 15 and 16 show a preferred embodiment of a rotating magnetic field transmitter +00, which is suitable for monitoring a tunnel boring machine, for example as schematically shown in FIG. 10 or 11. FIG. The transmitter includes a transducer assembly 102 and a non-metallic shaft 1
04 and means 106 for rotating the shaft 104.

Transducer assembly 102 is essentially the same as the transducer assembly described with reference to FIGS. 7-9. However, it has been found preferred that the ferromagnetic member 108 is a laminated steel core. This is because the laminated steel core can transmit high power. For simplicity of construction, element 108 is formed by a pair of parallel sections, each consisting of a laminated structure of rectangular sheets. To accommodate these, the shaft 104 has an angled slot 110 (see FIG. 16) in its central portion 112. The two parts of element 108 are fastened together around shaft 104 by a fastening bolt 114 that passes through a hole in the end part of element 108 and threads into a nut.

The excitation coil 116 wound on the spool 118 is
108 is formed so as to hold it tightly. Thus, when assembling the device, element 108 follows coil 116.
must be installed. Two parts can be easily inserted into each hole 1
After being inserted into 10, they are connected to each other by bolts. To balance the 'It element 10a around the rotor 104, the position of the element 108 can be microadjusted by a variable link extending from the bolt 114 to the shaft 104. Each link includes a non-metallic fastening rod 120 extending between portions of element 108 and a non-metallic fastening rod 120 extending from fastening rod 120 to shaft 104.
An elongated non-magnetic bolt 122 extends through it to a range that can be adjusted by m.

Each bolt 122 carries a non-gold bibalance weight 124 that balances against the forces produced by element 108 as shaft 104 rotates.

The rotating means 106 is a motor 1 connected to the shaft 104.
26, and the shaft 104 is journaled in a bearing 128 mounted on the non-magnetic end 1130. End plate 13
A cylindrical housing part 132,134 is installed between the coil spool 11
8 to hold the spool 118.

The receiver 136 for providing the reference signal is formed as a longitudinal coil wound on a ferrite rod. The coil is located within a radial cavity in one end plate 130.

The electronic systems required to capture data from the rotating magnetic field of the transmitting element from the received signal are not described, as several different techniques and circuits can be devised by those skilled in the art, and This is because they are used in guidance systems that involve wireless communication between the guided object and a receiving or control station.

Of course, the devices and methods (and parts thereof) described above can be used in different conditions and combinations, and for different purposes.

[Brief explanation of the drawing]

Fig. 1 is a side view of a device showing an embodiment of the present invention, Fig. 2 is a front view of an embodiment of the device, and Figs. 3a to 3d are views similar to Fig. 1 for explaining the operation. , FIG. 4 is a graph of the detector output, FIGS. 5 and 6 are views similar to FIG. 1 showing another embodiment of the invention, and FIG. 7a is a second diagram with a donut-shaped detector. FIG. 7b is a side view in cross section of the detector of the device of FIG. 7a; FIGS. 8a and 8b are views similar to FIG.
9 is a graph for explaining the operation of the embodiment shown in FIG. 8; FIG. 10 is a vertical sectional view of a tunnel excavator assembly using the device of the present invention; FIG. 11 is a perspective view of another tunnel boring machine assembly using the device of the present invention; FIGS. FIG. 14 is a view similar to FIG. 13 showing another embodiment; FIG. 15 is a practical example of a transmitter assembly for a tunnel excavator; The axial sectional view showing the embodiment, FIG. fj416, is a detailed view of the main part of the device shown in FIG. 15, viewed from another direction. 10i104...Shaft, 14;108...Ferromagnetic element, 16;116...Exciting coil. Cleaning of the blank drawing below (no changes in J) Fta, 2 (::1o, 3. Fw;, 3b Day 0.3c
FIG, 3dFtcy, 4 Fta, 9 Procedural amendment (method) August 13, 1985 Commissioner of the Patent Office Black 1) Akio Yu 1, Indication of the case 1986 Patent Application No. 103243 2, Title of invention Electromagnetic transducer Assembly and means for measuring relative velocity and/or position using the assembly 3, relationship to the amended case Patent applicant name: Radio Detection Limited 4, agent address: 105 Toranomon, Minato-ku, Tokyo -Chome 8th 1O No. 6,
Subject of amendment (1) “Representative of applicant” column of application 12) Power of attorney (3) Drawing 7, contents of amendment 111 (as shown in Appendix 21 (3) Engraving of drawing (no change in content) 8 List of attached documents J11 Correction application 1 copy (2) Power of attorney and translation 1 copy each (3) Engraved drawings 1 copy

Claims (1)

[Claims] 1. A transducer for producing a changing magnetic field, comprising: a shaft (10; 104) having an axis of rotation; an elongated ferromagnetic element (14; 108) disposed on said shaft (10; 104) so as to extend; and an excitation coil (16; 116);
6; 116) is longitudinally aligned with the elongated ferromagnetic element (14; 108) in the direction of magnetization such that the path of the current through the excitation coil (16; 116) depends on the direction of the current in the excitation coil (16; 116). A ferromagnetic element (14
; 108), whereby a swirling magnetic field can be generated by rotation of the shaft (10; 104) while an alternating current is passed through the excitation coil (16; 116). 2. Transducer according to claim 1, in which the excitation coil (16; 116) is substantially coaxial with the axis of rotation of the rotatable shaft (14; 104). 3. A transducer-receiver assembly comprising a transducer according to claim 1 or 2, comprising at least one receiver (22) capable of generating an electrical signal when subjected to a changing magnetic field. ;40a,
40b; 40c, 40d; 41; 51, 53, 54; 7
8; 136). 4. Transducer according to claim 3
In the receiver assembly, at least one said receiver comprises a detection coil (22; 22, 40a, 40b) and at least one said receiver comprises an excitation coil (16).
a transducer-receiver assembly arranged so that there is substantially no direct inductive coupling therebetween; 5. Transducer according to claim 3
In the receiver assembly, a plurality of receivers (22
, 40a, 40b). 6. Transducer according to claim 3
A transducer-receiver assembly, wherein at least one of said receivers comprises a toroidal coil (41; 78) disposed substantially coaxially with respect to the axis of rotation of the shaft. 7. Any one of claims 3 to 6
In the transducer-receiver assembly described in
The receiver (22a, 40a, 40b; 44; 51, 5
signal processing means (39; 48; 62; 70) connected to at least one of 3, 54, 66) and receiving electrical signals;
It further comprises signal processing means (39; 48; 62;
70) is configured to calculate and display data regarding the rotation of the shaft (10; 104) from the electrical signals. 8. Any one of claims 3 to 7
In the transducer-receiver assembly described in
The receiver comprises a donut-shaped coil (41; 78), which has a plurality of taps at different angular positions of the coil, by which a multiphase electrical signal can be input. Transducer-receiver assembly with removable parts. 9. Any one of claims 3 to 8
comprising a transducer-receiver assembly as described in
An apparatus for monitoring the position and orientation of an object (50), the transducer-receiver assembly comprising a transmitter assembly and a receiver assembly that are mutually replaceable; a monitoring device, one of which is adapted to be attached to said object; 10. A monitoring device according to claim 9, wherein the transmitter assembly comprises a reference receiver (40d; 53; 136) fixed relative to the transducer, the reference receiver (40d; 53; ; 136) is adapted to generate an electrical signal when subjected to a varying magnetic field by the transducer, and the monitoring device is further connected to the reference receiver and at least one receiver (51, 54) of the receiver assembly. a monitoring device comprising data processing means (62; 70) for receiving respective signals from said signals, said data processing means being adapted to compare said signals. 11. The monitoring device according to claim 9 or 10, wherein the receiver assembly (51, 54) is attached to the object (50), and the transmitter assembly is separated from each other. A monitoring device comprising at least two transducers (T_1, T_2, T_3) in different positions. 12. A monitoring device according to any one of claims 9 to 11, wherein the receiver assembly comprises two receivers (51, 54), said two receivers (5
1, 54) has a magnetic axis, and the two receivers (51, 54) have a magnetic axis;
54) whose axes lie in mutually perpendicular planes. 13. In the monitoring device according to any one of claims 9 to 11, the receiver assembly comprises a coil (41;
78). 14. The monitoring device according to claim 13, wherein the receiver assembly comprises a toroidal or substantially toroidally wound coil (80; 82a, 82b) and a longitudinally wound coil (86). ), wherein the coils are arranged coaxially. 15. An apparatus for monitoring the position and orientation of an object, comprising a transmitter assembly and a receiver assembly that are mutually replaceable, wherein one of the transmitter assembly and the receiver assembly is connected to the object. The transmitter assembly includes at least one coil assembly longitudinally connected to a toroidal or substantially toroidal wound coil (80; 82a, 82b). A monitoring device comprising a wound coil, said coil being arranged coaxially.