INDICATOR FOR INDICATING THE STRENGTH OF AN ALTERNATING MAGNETIC FIELD OF A PRIMARY CONDUCTOR

Description

[0001] The invention relates to a display means for displaying the strength of an alternating magnetic field of a primary conductor.

[0002] It is well known that an alternating magnetic field induces an alternating voltage in a coil.

[0003] From the US 4 775 832 A A display means for displaying the strength of an alternating magnetic field of a primary conductor is known, wherein the display means comprises an oscillating circuit.

[0004] From the DE 32 35 535 A1 A display device for locating metal objects and for displaying the strength of alternating electric fields of a primary conductor by means of an oscillating circuit is known.

[0005] From the EP 0 551 606 A2 A metal detector with an oscillating circuit is known.

[0006] From the DE 10 2015 012 439 B3 The closest prior art is a system for the inductive transmission of electrical energy from a primary winding to the secondary winding of a vehicle that can be moved on a floor.

[0007] A wireless resonant transmission of electrical energy is known from XP 055672293.

[0008] From the US 2 931 974 A A geophysical exploration method is known.

[0009] From the WO 2012 / 143082 A1 A system for inductive energy transfer to a consumer is known.

[0010] From the US 2014 / 139223 A1 A field gradient antenna is known.

[0011] From the WO 2015 / 087736 A1 A magnetic detection device is known.

[0012] From the EP 2 053 426 A1 is a display unit for a metal detector.

[0013] The invention is therefore based on the object of designing a display means.

[0014] According to the invention, the object is achieved by the display means according to the features specified in claim 1.

[0015] Important features of the invention in the display means for displaying the strength of an alternating magnetic field of a primary conductor are that the display means comprises one or more luminous means, wherein the display means comprises a housing which has flat surface sections whose respective normal directions are not aligned parallel to one another, in particular wherein or wherein the display means comprises a cube-shaped, cuboid-shaped, tetrahedral or polyhedral housing, wherein the display means has an inductance forming an oscillating circuit with a capacitance, wherein the illuminating means or means can be supplied from the oscillating circuit.

[0016] The advantage here is that the indicator does not require an energy storage device and reacts specifically to the resonant frequency of the oscillating circuit. Thus, only the strength of the alternating magnetic field at the resonant frequency is detected. The indicator can therefore be used as an indicator for detecting an operating state in a system.

[0017] In an advantageous embodiment, the resonant circuit is a parallel resonant circuit or a series resonant circuit. The advantage here is that a correspondingly high voltage can be provided.

[0018] According to the invention The inductor has a coil core and a coil winding wound around it. The advantage here is that the inductor is easy to manufacture.

[0019] According to the invention The coil core has three core parts, each aligned perpendicularly to the other two, with a partial winding of the coil winding wound around each of the core parts. The coil winding is formed from the partial windings connected in series. The advantage here is that the strength of the magnetic field can be detected regardless of the orientation of the display unit.

[0020] In an advantageous embodiment, the housing is made of an optically transparent material. This advantageously allows the illuminant to be arranged inside the housing.

[0021] In an advantageous embodiment, the respective light source(s) is arranged in a recess extending through the housing. This is advantageous because it allows for simple manufacturing.

[0022] In an advantageous embodiment, the respective light source is arranged inside the housing, surrounded by the housing. This is advantageous because the light source is easy to protect.

[0023] In an advantageous embodiment, the light source(s) are powered, in particular exclusively, by the oscillating circuit. This is advantageous because no energy storage device, such as a battery or accumulator, is required for the display device.

[0024] Important features of the system with the aforementioned display means are that a primary conductor designed as a line conductor and supplied with alternating current is laid in a floor of the system, in particular below a floor level, wherein the display means is arranged on the surface of the floor, in particular on the floor level.

[0025] The advantage here is that the line conductor can be detected by means of the display device when it is subjected to an alternating current whose frequency is equal to the resonant frequency of the oscillating circuit of the display device.

[0026] Further advantages emerge from the dependent claims. The invention is not limited to the combination of features in the claims. Further possible combinations of claims and / or individual claim features and / or features of the description and / or the figures will become apparent to those skilled in the art, particularly from the problem and / or the problem posed by comparison with the prior art.

[0027] The invention will now be explained in more detail using schematic illustrations: In the Figure 1 a display unit is shown at two different distances to a primary conductor 3. In the Figure 2 A first electronic circuit of the display unit is schematically sketched. Figure 3 An alternative second electronic circuit of the display unit is schematically sketched.

[0028] As in Figure 1As shown, a system has an elongated primary conductor 3, whose magnetic field is Figure 1 is shown schematically. The display unit has an LED 2 as a light source, which does not light up when the distance from the primary conductor 3 is large and lights up when the distance from the primary conductor 3 is small.

[0029] This is done with the Figure 2 shown electronic circuit, which is arranged in the display means.

[0030] As in Figure 2 As shown, an inductance is provided which can be inductively coupled to the primary conductor 3, so that an induced voltage can be provided at the terminals of the inductance if the coupling to the primary conductor is sufficiently strong, in particular if the distance falls below a threshold value.

[0031] The voltage provided by the inductance can be used to supply a series circuit formed by the lamp and a capacitor.

[0032] The inductance and capacitance are dimensioned in such a way that the series resonant circuit thus formed when the light source is neglected has a resonant frequency which is equal to the frequency of the alternating current impressed into the primary conductor.

[0033] As soon as the magnetic field generated by the primary conductor at the location of the inductance of the display unit exceeds a first threshold value, the lamp lights up.

[0034] In the alternative embodiment according to Figure 3 is instead of the series resonant circuit according Figure 2 A parallel resonant circuit is provided. The lamp, the inductance, and the capacitor are connected in parallel.

[0035] The examples according to Figure 2 and Figure 3switch the lamp on at different magnetic field strengths because different voltages are provided by the series resonant circuit or parallel resonant circuit with an alternating magnetic field of the same strength.

[0036] The display unit has a cubic or at least cuboid-shaped housing. Thus, the inductance can be provided by a coil whose coil core, preferably made of ferrite, can be positioned in a well-defined position relative to the primary conductor, since the display unit can be placed on the floor.

[0037] The primary conductor 3 is laid as an elongated line conductor in the ground, i.e., arranged in a horizontal position. Thus, the primary conductor 3 is located below the ground level, on which the display unit can be positioned. When approaching the primary conductor 3, i.e., when the distance decreases and the magnetic field becomes stronger, the lamp begins to illuminate at a certain position.

[0038] Preferably, the display unit is displaced, particularly at ground level, along the plane whose normal direction is parallel to the direction of the line conductor, i.e., primary conductor 3. The relative spatial orientation of the display unit with respect to primary conductor 3 always remains the same.

[0039] Since the inductance and the capacitance form a series resonant circuit at Figure 2 or a parallel resonant circuit at Figure 3 form.

[0040] The light source 2 is arranged in a recess extending through the housing.

[0041] In further embodiments of the invention, the housing of the display unit is a tetrahedron.

[0042] In further embodiments according to the invention, a light source is arranged on each of the side surfaces of the polyhedral housing, in particular, the light sources being connected either in series or in parallel. The light sources then begin to illuminate simultaneously when a sufficiently strong magnetic field is present.

[0043] In further embodiments according to the invention, the housing is made of an optically transparent material so that the illuminant(s) can be arranged inside the display unit.

[0044] In further embodiments according to the invention, a first and a second illuminating means are arranged on the housing, wherein the electronic circuit is designed such that the first illuminating means illuminates when the strength of the alternating magnetic field lies between a first and a second threshold. However, the second illuminating means only illuminates when the strength of the alternating magnetic field lies above the second illuminating means.

[0045] The second threshold value is greater in magnitude than the second threshold value. List of reference symbols

[0046] 1 Housing part 2 LED 3 Primary conductor

Claims

1. Display means for displaying the strength of an alternating magnetic field of a primary conductor (3), wherein the display means has one or more illumination means (2), wherein the display means has an inductor that forms a resonant circuit together with a capacitor, wherein the one illumination means or the plurality of illumination means (2) can be powered from the resonant circuit, characterised in that the display means has a housing (1) that has planar surface portions, the respective normal directions of which are not oriented in parallel with one another, wherein the inductor has a coil core and a coil winding wound around said coil core, wherein the coil core has three core parts, each oriented perpendicularly to the other two, wherein one part-winding of the coil winding is wound around each of the core parts, wherein the coil winding is formed from the part-windings, which are connected in series with one another.

2. Display means according to claim 1, characterised in that the display means has a cube-shaped, parallelepiped-shaped, tetrahedron-shaped or polyhedron-shaped housing (1).

3. Display means according to claim 1 or claim 2, characterised in that a series circuit, formed of the one illumination means or of one of the plurality of illumination means (2) and the capacitor, which is configured as a condenser, can be powered from the voltage that can be provided by the inductor, wherein the resonant circuit has a resonant frequency that is equal to the frequency of the alternating current impressed on the primary conductor (3).

4. Display means according to any of the preceding claims, characterised in that the housing (1) is made of an optically transparent material.

5. Display means according to any of the preceding claims, characterised in that the one illumination means or the plurality of illumination means (2) is / are in each case arranged in a through-opening that extends through the housing (1) or in that each illumination means (2) is arranged in the housing interior enclosed by the housing (1).

6. Display means according to any of the preceding claims, characterised in that the one illumination means or the plurality of illumination means is / are powered solely from the resonant circuit.

7. Facility comprising a display means according to any of the preceding claims, characterised in that a primary conductor (3) which is in the form of a line conductor and to which alternating current is applied is installed in a floor of the facility, i.e. in particular below a floor level, wherein the display means is arranged on the surface of the floor, in particular on the floor level.