DE102016003993A1 - Arrangement for determining the position and / or speed of a movable part - Google Patents

Abstract

Arrangement for determining the position and / or speed, in particular angular position and / or rotational speed, of a movable part, wherein the arrangement - a permanent magnet having permanent magnet arrangement - a, in particular on its side facing the permanent magnet side, equipped with sensors circuit board - flow guide parts and a return part wherein permanent magnets are arranged one behind the other in the direction of movement, wherein between the respective sensor and the permanent magnet arrangement, a respective flux guide member is arranged, wherein on the side facing away from the flux guide parts of the circuit board, the return part is arranged.

Description

The invention relates to an arrangement for determining the position and / or speed of a movable part.

It is well known that the magnetic field of permanent magnets is detectable by means of Hall sensors.

From the JP 2013-128 377 A An arrangement for determining the position and / or speed is known.

From the DE 103 29 150 A1 An electric machine is known.

From the DE 38 01 171 C1 a device for detecting the rotational speed of the shaft of an exhaust gas turbocharger is known.

The invention is therefore based on the object to develop an arrangement for determining the position.

According to the invention the object is achieved in the arrangement according to the features indicated in claim 1 or 10.

• – eine Dauermagnete aufweisende Dauermagnetanordnung
• – eine, insbesondere auf ihrer den Dauermagneten zugewandten Seite, mit Sensoren bestückte Leiterplatte,
• – Flussführungsteile und ein Rückschlussteil

aufweist,
wobei Dauermagnete in Bewegungsrichtung hintereinander angeordnet sind,
wobei zwischen dem jeweiligen Sensor und der Dauermagnetanordnung ein jeweiliges Flussführungsteil angeordnet ist,
wobei auf der von den Flussführungsteilen abgewandten Seite der Leiterplatte das Rückschlussteil angeordnet ist.Important features of the invention in the arrangement for determining the position and / or speed, in particular angular position and / or rotational speed, of a movable part, are that the arrangement

• - A permanent magnet having permanent magnet assembly
• A printed circuit board equipped with sensors, in particular on its side facing the permanent magnet,
• - Flow guide parts and a return part

having,
wherein permanent magnets are arranged one behind the other in the direction of movement,
wherein a respective flux guide part is arranged between the respective sensor and the permanent magnet arrangement,
wherein on the side remote from the flow guide parts of the circuit board, the return part is arranged.

It is advantageous in this case that a magnetic flux generated by the permanent magnet arrangement can be conducted through the flux guide parts to form a return element, in which the magnetic fluxes introduced by the flux guide elements add up vectorially. Therefore, the effective flux present in the return part is essentially vanishingly small.

In an advantageous embodiment, the permanent magnets each have the same length in the direction of movement and / or the permanent magnets are regularly spaced apart in the direction of movement. The advantage here is that a simple production is executable.

In an advantageous embodiment, the permanent magnets have a direction of magnetization perpendicular to the direction of movement,
wherein directly adjacent permanent magnets have mutually reverse magnetization direction. The advantage here is that the magnetization direction is transversal. In the case of rotational movement, a radially or axially directed magnetization is thus advantageous.

• – bei gleichmäßiger Bewegung des bewegbaren Teils die Sensorsignale eines jeweiligen Paares von Sensoren um m·360°/N zueinander verschoben sind, wobei N die Anzahl der Sensoren und m eine natürliche Zahl zwischen 0 und N, insbesondere eins oder zwei, ist,
• insbesondere wobei zu jeder natürlichen Zahl zwischen 0 und N mindestens ein Paar zuordenbar ist.

In an advantageous embodiment, the spacing of the flow guide parts, in particular the end regions facing the permanent magnet arrangement, in particular end faces, of the flux guide parts in the direction of movement is such that

• With uniform movement of the movable part, the sensor signals of a respective pair of sensors are shifted by m.sup.360.degree. / N relative to one another, where N is the number of sensors and m is a natural number between 0 and N, in particular one or two,
• in particular, wherein at least one pair can be assigned to each natural number between 0 and N.

The advantage here is that a sine / cosine evaluation is executable and / or from the course of the sensor signals, the angular position or its course can be determined and optionally the rotational speed.

In an advantageous embodiment, the permanent magnets are arranged such that the magnetic field generated by the permanent magnet arrangement has a period length L in the direction of movement,
wherein the distance of the flux guide parts, in particular of the permanent magnet assembly facing end portions, in particular end faces, the flow guide parts in the direction k · L + m · L / N, where N is the number of sensors and k is a natural number and m is a natural number between 0 and N is,
in particular, wherein at least one pair of flow guide parts can be assigned to any natural number between 0 and N. The advantage here is that a highly accurate determination of the angular position is possible.

In an advantageous embodiment, an air gap is arranged between the permanent magnets of the permanent magnet arrangement and the respective flow guide part. The advantage here is that no Contact between the non-rotatably connected to the rotatable member permanent magnet and the stationary flow guide parts occurs.

In an advantageous embodiment, the direction of movement is the direction of rotation and / or circumferential direction, wherein the magnetization direction is designed radially or axially,
in particular, wherein a normal of the circuit board plane intersects the axis of rotation of the rotatable part and / or the circuit board plane is aligned parallel to the axis of rotation of the rotatable part. The advantage here is that a rotary design is easy to produce.

In an advantageous embodiment, the sensors fitted on the printed circuit board are arranged in an air gap between the flow guide part and the return part. The advantage here is that the sensors can be arranged in a plane, although the permanent magnet assembly is designed like a ring, especially as glued to a ring permanent magnets.

In an alternative embodiment, each flow guide part is wrapped with a winding which acts as a sensor,
wherein the return part touches the flow guide parts respectively. The advantage here is that no air gap between the return part and flow guide parts is arranged.

In an advantageous embodiment, the sensors are designed as Hall sensors. The advantage here is that a simple detection is executable.

In an advantageous embodiment, the return part and flow guide parts are made of ferrite. The advantage here is that a cost-effective production is possible.

Further advantages emerge from the subclaims. The invention is not limited to the combination of features of the claims. For the skilled person, further meaningful combination possibilities of claims and / or individual claim features and / or features of the description and / or figures, in particular from the task and / or posing by comparison with the prior art task arise.

The invention will now be explained in more detail with reference to figures:

In the 1 an arrangement according to the invention for detecting the angular position of a rotatably mounted part is shown schematically.

In the 2 is an enlarged section of the 1 shown.

In the 3 an oblique view of the arrangement is shown.

As shown in the figures, the rotatably mounted part is a ring 2 executed on the circumferentially one behind the other permanent magnets 1 are arranged.

It points to one of the permanent magnets 1 each adjacent circumferentially next permanent magnet 1 a reverse magnetization direction.

The magnetization direction is preferably provided in the radial direction or opposite to the radial direction.

At three circumferentially spaced locations are flux guide members 3 arranged, which has a small radial distance to the ring 2 and the permanent magnet 1 exhibit. Between the permanent magnets 1 and the respective end region of the respective flow guide part 3 So each one air gap is provided. The permanent magnets 1 are arranged equidistantly in the circumferential direction and / or each have the same length in the circumferential direction. The spacing of the points is chosen such that, with a uniform rotational speed, the time profile of the amount of the flow introduced into the respective flux guide part has a phase-shifted phase by 120 ° in comparison to one of the two other flux guide parts 3 having.

The flow guide parts 3 conduct the flow at its other end region via a respective further air gap in a return part 4 which acts as a magnetic inference. For this purpose, only a single integrally executed return part 4 intended.

A circuit board 5 is with sensors 6 equipped, wherein in the respective further air gap in each case a sensor 6 is arranged. In this way, the magnetic flux is in the respective flux guide part 3 determinable. As a result of the common conclusion part 4 The superimposed river disappears.

By the assembly of the printed circuit board 5 is a simple production allows, wherein the evaluation unit for the evaluation of the sensor signals also on the circuit board 5 can be equipped.

The flow guide parts 3 each run from the sensor 6 to the ring 2 with the permanent magnets 1 , The normals of the next adjacent permanent magnet 1 facing, just shaped Surface portion of the end portion is directed in each case in the radial direction. These surface sections are thus on the permanent magnets 1 directed towards. Because the flow guide parts 3 however, to those on the circuit board 5 arranged sensors 6 extend and also there the normal of each of the circuit board 5 facing, just shaped surface portions, ie end faces, the end portion are aligned parallel to the normal of the circuit board level, at least two of the flux guide parts must be curved. A rectilinear design is therefore only with a flow guide part 3 executable. In this case, the axis of rotation of the rotatably mounted part is aligned parallel to the printed circuit board plane.

Preferably, the flow guide parts 3 and the rear part 4 made of ferrite or of another soft magnetic material.

The conclusion part 4 is on the of the river guide parts 3 opposite side of the circuit board 5 arranged. Thus, in the respective air gap between the respective flow guide part 3 and the rear part 4 only the respective sensor 6 and a printed circuit board area.

The vertical, so in the radial direction projections of the end portions of the flow guide parts 3 on the outer surface of the ring 2 are circumferentially spaced from each other such that the distance from the first to the second projected area two thirds or four-thirds of the regular distance between two adjacent permanent magnets 1 is, where integer multiples of this regular distance can be added.

The permanent magnets 1 are made equal in the circumferential direction and spaced from each other regularly. Thus, the distance between two circumferentially successively arranged permanent magnet is the same.

The respective circumferentially adjacent permanent magnet 1 is magnetized in the opposite direction. Thus, the period length of the arrangement in the circumferential direction is twice the distance between two circumferentially adjacent permanent magnets 1 , The distance between the first and circumferentially adjacent projected region of the respective flow guide part 3 is an integer multiple of the period length plus one third of the period length. The distance between the third and opposite to the circumferential direction next adjacent projected area of the respective flow guide part 3 is also an integer multiple of the period length plus one third of the period length.

Thus, the distance between the first and in the circumferential direction after the second, so third, projected area of the respective flow guide part 3 an integer multiple of the period length plus a two-thirds of the period length.

Upon rotation of the pole wheel thus the curves of the sensor signals of the sensors 6 each shifted by 120 ° or 240 ° to each other.

By evaluating the sensor signals, the relative angle of rotation to an initial position can thus be determined and / or the rotational speed, ie the rotational speed of the ring 2 ,

As sensors 6 Hall sensors are particularly suitable here.

In a further embodiment according to the invention, there is no air gap between the return part and the respective flow guide part 3 available. Thus, lower losses are present. But then there are the sensors 5 can not be arranged in an air gap, each of the flow guide parts 3 wrapped with a winding and the induced voltage detected and evaluated. From the voltage curves, the angular ranges covered and / or the rotational speed are thus determined. However, a minimum speed is necessary, which depends on the sensitivity threshold of the voltage detection, ie the value of the smallest, detectable, non-zero voltage.

In a further embodiment of the invention, the flow guide parts 3 executed interrupted on a housing wall, so that a simple seal and / or installation can be achieved. Particularly advantageously, the housing wall is made of plastic or aluminum or other non-magnetic material, in particular therefore not ferromagnetic, not antiferromagnetic, non-ferrimagnetic and not antiferrimagnetischem material. A diamagnetic material is therefore particularly well suited.

In a further embodiment of the invention is / are the ring 2 and / or the permanent magnets 1 in a fan of an electric machine, in particular electric motor, integrated.

In a further embodiment of the invention, a sine / cosine evaluation of the sensor signals is provided, since thus the angular position and the speed can be executed in a simple and inexpensive manner.

In a further embodiment of the invention is an axial direction of magnetization of permanent magnets 1 provided wherein the circumferentially directly adjacent permanent magnets each have reverse magnetization direction. Thus, then the sensors and / or flux guide elements 3 axially behind the permanent magnets 1 arranged.

In a further embodiment of the invention, the arrangement is not rotational but linear. Thus, the embodiments are carried out, so to speak, unrolled.

LIST OF REFERENCE NUMBERS

1

permanent magnets

2

ring

3

River guide part

4

Return part

5

circuit board

6

Sensor, in particular Hall sensor

QUOTES INCLUDE IN THE DESCRIPTION

This list of the documents listed by the applicant has been generated automatically and is included solely for the better information of the reader. The list is not part of the German patent or utility model application. The DPMA assumes no liability for any errors or omissions.

Cited patent literature

• JP 2013-128377 A [0003]
• DE 10329150 A1 [0004]
• DE 3801171 C1 [0005]

Claims (11)

Arrangement for determining the position and / or speed, in particular angular position and / or rotational speed, of a movable part, the arrangement comprising a permanent magnet arrangement having permanent magnets, a printed circuit board equipped with sensors, in particular on its side facing the permanent magnet, flow guide parts and a return part wherein permanent magnets are arranged one behind the other in the direction of movement, characterized in that between the respective sensor and the permanent magnet arrangement, a respective flux guide member is arranged, wherein on the side facing away from the flux guide parts of the circuit board, the return part is arranged. Arrangement according to claim 1, characterized in that the permanent magnets each have the same length in the direction of movement and / or the permanent magnets are regularly spaced apart in the direction of movement. Arrangement according to at least one of the preceding claims, characterized in that the permanent magnets have a direction of magnetization perpendicular to the direction of movement, wherein directly adjacent permanent magnets have mutually reverse magnetization direction. Arrangement according to at least one of the preceding claims, characterized in that the spacing of the flow guide parts, in particular of the permanent magnet arrangement facing end portions, in particular end faces of the flow guide parts are spaced apart in the direction of movement such that - with uniform movement of the movable member, the sensor signals of a respective pair of Sensors are shifted by m · 360 ° / N to each other, where N is the number of sensors and m is a natural number between 0 and N, in particular one or two, in particular wherein at any natural number between 0 and N at least one pair is assigned , Arrangement according to at least one of the preceding claims, characterized in that the permanent magnets are arranged such that the magnetic field generated by the permanent magnet arrangement in the direction of movement has a period length L, wherein the distance of the flux guide parts, in particular of the permanent magnet assembly facing end portions, in particular end faces, the Flow direction parts in the direction of movement k · L + m · L / N, where N is the number of sensors and k is a natural number and m is a natural number between 0 and N, in particular where each natural number between 0 and N at least one pair is attributable to flow guide parts. Arrangement according to at least one of the preceding claims, characterized in that an air gap is arranged between the permanent magnets of the permanent magnet arrangement and the respective flux guide part. Arrangement according to at least one of the preceding claims, characterized in that the movement direction is the direction of rotation and / or circumferential direction, wherein the magnetization direction is carried out radially or axially, in particular wherein a normal of the printed circuit board plane intersecting the axis of rotation of the rotatable member and / or the printed circuit board plane parallel to the Rotary axis of the rotatable part is aligned. Arrangement according to at least one of the preceding claims, characterized in that the assembled on the circuit board sensors are arranged in an air gap between the flow guide part and the return part. Arrangement according to at least one of the preceding claims, characterized in that the sensors are designed as Hall sensors. Arrangement, in particular according to at least one of claims 1 to 7, for determining the position and / or speed, in particular angular position and / or rotational speed, of a movable part, wherein the arrangement - a permanent magnet having permanent magnet assembly - a circuit board, - windings - flow guide parts and a return part, wherein permanent magnets are arranged one behind the other in the direction of movement, wherein between the respective sensor and the permanent magnet arrangement, a respective flux guide member is arranged, wherein on the side facing away from the flow guide parts of the circuit board, the return part is arranged. characterized in that each flux guide part is wound with a winding which acts as a sensor, wherein the return part touches the flux guide parts respectively. Arrangement according to at least one of the preceding claims, characterized in that the return part and flow guide parts are made of ferrite.

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