DE102004013022B3 - Electric motor has section counter, which features a stationary and a moving part for a stable drive - Google Patents

Abstract

The first of the two parts facing the surface of the other part has alternating areas with differing magnetic permeabilities. The second part features permanent magnets and sensors, so that a magnetic flow, which is generated by the permanent magnets, is available in the respective sensitivity ranges of the sensors. The value and the direction of the magnetic flow within the respective sensitivity range are dependent on the position of the first part and are alterable in such a way that by means of the sensors, signal voltage pulses are generatable. The invention features at least a rotor and a stator, whereby the stator and rotor, in a first axial section, are designed as an asynchronous, a synchronous or a reluctance motor. In the second axial section the surface of the rotor, which faces the stator, features alternating recesses and increases, whereas the stator features permanent magnets and sensors, so that the magnetic resistance, dependent on the rotor position, is variable in such a manner that by means of the sensors signal voltage pulses can be generated.

Description

The The invention relates to a section counter and a drive.

One Drive comprises at least one linear or rotary electric motor. When rotary electric motor is also an optionally from the electric motor includes driven gear from the drive.

From the EP 0 724 712 B1 is known as a section counter a rotation angle sensor, on whose rotor magnets are provided, which have an alternating direction of magnetization in the circumferential direction. At the periphery stationary Wiegand sensors, ie pulse-wire sensors and / or voltage-generating motion sensors are provided, which deliver a voltage pulse at its exit when passing a respective magnet, which is provided to an electronic circuit.

adversely is in the process of providing magnets on the rotor. They have to be like that be attached to the centrifugal forces even at high speeds resist. In a linear instead of rotary execution of the Rotation angle sensors would have disadvantageously along the rotor so along the route many Magnets are attached. This leads to extremely high costs the production and corresponding costs.

From the EP 1 310 771 A1 a pulse signal generator is known in which according to the description, in particular column 2, line 46 to column 3, line 5, of the sensor moved past teeth that magnetic field acting on the magnet wire 1, is so variable that Barkhausen jumps generated are detectable.

adversely is that the sensitivity range is very small and the Signal-to-noise ratio the signal is usable only with very strong teeth. Especially Only a small part of the generated by the permanent magnets Magnetic flux passed through the pulse wire.

From the DE 102 59 223 B3 a position detector is known in which the movable part comprises magnets whose generated magnetic flux is guided via an air gap to a pulse wire. The disadvantage here is that in the case of a linear design, many magnets are necessary on the movable part and thus high costs arise. In addition, a connection point is necessary for each magnet, which thus also represents a weak point.

From the DE 600 03 067 T2 a security system is known in which a sensor with the magnets is mounted together on a part. However, the sensor is just a common coil and thus detects changes in the included flow. In the other, movable relative to the first part Barkhausen micro-wires are arranged whose magnetization folds when they come close to the magnet. The sudden field changes during folding result in relatively small flux changes in the sensor coil. The disadvantage here is that no downstream electronics can be supplied. In addition, a large part of the flow is not passed through the sensitive area of the sensor. The changes in the field flux, which can be effected by the Barkhausen microwires, are very small. Thus, disadvantageously, the signal-to-noise ratio is unfavorable. Because it is essential that the Barkhausen effect does not take place within the coil but far away from it. In addition, at the DE 600 03 067 T2 disadvantageous that at the other, relative to the first part movable part over the entire length of the microwires are provided. This is expensive and expensive. A further disadvantage is that the sensor used is a coil whose inductance must be determined (cf. DE 600 03 067 T2 Section [0041] and [0042]), for which a complex high-frequency electronics is necessary.

Of the The invention is therefore based on the object, a more stable drive and to develop the angular momentum sensor.

According to the invention Task at the section counter according to claim 1, 4, 5 or 28 and in the drive according to the solved in claim 21 specified characteristics.

basics Features of the invention in the section counter are that in rotary execution for counting Of angle sections, including as a revolution counter, in linear design for counting of linear sections, so also as odometer counter providable is.

In particular, it is essential that the section counter comprises a stationary part and a part movable relative thereto,
wherein a first of the two parts has alternating regions with different magnetic permeabilities along its surface facing the second of the two parts,
and that the second part comprises permanent magnets and sensors arranged in such a way that there is magnetic flux in the respective sensitivity ranges of the sensors, which is generated by the permanent magnets,
wherein the amount and the direction of the magnetic flux in the respective sensitivity range is variable depending on the position of the first part such that signal voltage pulses can be generated by means of the sensors.

From The advantage here is that a power fail-safe absolute-revolution counter produced is, in the case of rotary execution, the magnets stationary, ie are non-rotating vorsehbar and thus no centrifugal forces they work. The regions of different permeability are as increases and depressions and thus by means of molding on the solid body or as sheet package executable and thus keep all centrifugal forces was standing.

Vorteiligerweise are permanent magnets for generating magnetic flux providable, the flows essentially in at least two circles, the circles each both areas of the first and the second part include. First and second part are designed such that during the movement of the first Partly, ie the linear movement or rotational rotation of the first Part, the resulting in the sensitivity range of the sensor River, which from the superposition of the arises from the two circles flow shares, umpolbar is. Each sensor can be assigned to two such circles, the essential for the River in the sensitivity range are responsible. Vorteilig is in the invention that the first part in cheaper Just do areas have different magnetic susceptibility or permeability must and thus when moving the first part, the two respective Shares of the river in the sensitivity range differently strong pronounced are. The different degrees of severity are even predictable that a reversal of the resulting flow is achievable. To are also arranged in the second part yokes in a suitable manner.

On these are even Wiegand wires as Sensors can be used, which supply voltage pulses during polarity reversal.

at In an advantageous embodiment, the signal voltage pulses fed to an electronic circuit that derives from the energy of this Signal voltage pulses can be supplied and a counter for the pulses includes, wherein the count can be stored non-volatile is. The advantage here is that no further energy supply necessary is.

at According to an advantageous embodiment, the counter is a FRAM block, ie in FRAM technology, executed. In particular, there is no external supply for supplying the counter and no supply from other energy storage, such as batteries or like that, necessary. The advantage here is that energy-saving Technology is usable and the meter reading can be stored over long periods.

at an advantageous embodiment, the counter is a single block executed. The advantage here is that lower costs and lower susceptibility are reachable.

at According to an advantageous embodiment of the block of a rectifier circuit supplied, in turn, from the signal voltage pulses of the sensors is taken care of. The advantage here is that the supply of the device in easier and cheaper Way from the signals themselves are achievable.

at According to an advantageous embodiment, the sensors are pulse-wire sensors and / or Wieganddrahtsensoren. In particular, the sensors work after the Barkhausen effect. The advantage here is that known inexpensive Standard sensors are usable.

at an advantageous embodiment, the electric motor is linear or constructed rotationally. The advantage here is that both versions are covered by the invention and thus the advantages of both engines the invention can be achieved.

at an advantageous embodiment, the stator and rotor in a third axial range, a fine angle sensor. Advantageous is doing that a control and / or control of the electric motor according to the achievable to the fine angle sensor.

at According to an advantageous embodiment of the meter reading number of revolutions and / or partial revolutions again. In particular, are rotatory in execution three sensors provided. The advantage here is that a direction of rotation detection is possible.

at In an advantageous embodiment, the block is a bus subscriber accomplished or has an electrical interface for data transmission. The advantage here is that the meter reading can be transmitted to other devices is.

Essential features of the invention in the drive are that it comprises at least one electric motor comprising at least one movable part and a stator,
wherein the stator and the movable part are constructed in a first axial region in the manner of an asynchronous motor, synchronous motor or reluctance motor,
wherein the movable part in a second axial region along its surface facing the stator facing each other with ver has different magnetic permeabilities,
and that the second part, ie stator, comprises such arranged permanent magnets and sensors, that in the respective sensitivity ranges of the sensors magnetic flux is present, which is generated by the permanent magnets,
wherein the amount and the direction of the magnetic flux in the respective sensitivity range is variable depending on the position of the first part such that signal voltage pulses can be generated by means of the sensors.

From The advantage here is that in rotatory design, the magnets stationary, ie are non-rotating vorsehbar and thus no centrifugal forces on this Act. The raises and depressions are by means of molding on the solid body or executable as a laminated core and thus withstand all centrifugal forces.

Vorteiligerweise The electric motor is also integrated with that on its rotor shaft section counter executable. this makes possible a particularly compact and inexpensive design of the electric motor. Of the Drive is also associated with an electric motor included Gearbox executable.

Especially is the drive also a finely resolving sensor additionally providable. Thus, not only sections are detectable but also between the sensors lying in the sections.

1

rotor

2

yoke

3

sensor

4

permanent magnet

21

counters block

The invention will now be explained in more detail with reference to figures:
In the 1 a device according to the invention is shown schematically. Here is the rotor 1 shown linearly. However, the alternative rotary embodiment according to the invention takes place in a corresponding manner.

Rotor and stator are movable relative to each other. The rotor 1 has a variable thickness in the direction of movement, with elevations and depressions alternating. The stator comprises three E-shaped yokes 2 , Wherein on the two outer legs of the E permanent magnets 4 are arranged and the middle leg of the E of the sensor 3 is arranged. In this case, the sensor is arranged on the center leg of the E, that from the center leg of the E-shaped yoke exiting magnetic flux is passed through the sensor.

Of the Sensor is a voltage pulse generating detector which increases with increasing and / or decreasing magnetic flux generates a voltage pulse, So briefly generates a voltage. Advantageously, a Wiegand wire sensor, so a pulse wire sensor used.

When the rotor moves past the stator, the sensor detects 3 different magnetic flux, because the magnetic resistance between the legs of the E varies depending on the rotor position.

The yokes 2 are spaced apart and the sensors 3 are arranged parallel to each other and oriented in the same direction.

The stator comprises at least three sensors 3 and yokes 2 ,

The permanent magnets of two adjacent legs of two different and adjacent yokes 2 are oriented in opposite directions. Thus, so a minimum distance should be maintained in order to obtain a sufficient signal from the sensors.

at a rotary version the sensors are circumferentially arranged at 120 ° intervals such that the orientations of the sensors are always radial and to each next Neighbors 120 ° angled are aligned.

The signals of the sensors are according to 2 respectively supplied to diodes which charge a capacitor to which the supply voltage for a counter module 21 is removed. The counter module 21 is supplied by the momentarily generated voltage pulses. The signals are also fed to the counter module for evaluation, in particular for counting.

at rotary design three voltage pulses are generated per revolution. The meter reading of the meter counts however only the pules of one of the three sensors, which in the following also as Reference pulse sensor is beschzeichenbar.

Because three sensors are arranged on the circumference, the direction of rotation is recognizable and the meter reading is thus an absolute value counter for turns usable. Advantageously, counts the meter reading So up and down depending on the detected direction of rotation.

The counter module 21 has an interface, which allows data transmission to other electronic devices or bus subscribers is.

The counter module 21 saves the counter reading to a non-volatile memory. Particularly advantageous here is the FRAM technology. Thus, the counter module can be supplied solely from the voltage pulses and requires no further power supply. For data exchange with other bus participants, however, an additional power supply is advantageous, especially in slow or non-rotating motor.

The Sensors together form a section counter. at rotatory execution so counted angle sections and in linear design linear sections are counted.

at other embodiments of the invention be instead of the increases and recesses each material areas with different permeability arranged. Thus, different in the movement of the rotor strongly magnetizable areas in the sensitivity range of respective sensors. Advantageously, such an embodiment is also very easy and inexpensive to manufacture. With linear design are the costs for the rotor is very low and in rotary design is a high stability against centrifugal forces achievable.

In further embodiments of the invention are according to 3 orienting the orientations of the adjacent sensors in opposite directions. Thus, the permanent magnets can be oriented differently by 180 °. This results in the advantage that the yokes are providable without spacing. The magnetic fields of the directly adjacent permanent magnets do not weaken.

For rotary execution of a 3 constructed speed sensor, three sensors are arranged, thereby direction detection is enabled. The sensors are all radially aligned and arranged, for example, rotated by 90 ° to the nearest neighbor. The three associated yokes are touchingly mountable, with the first and third not touching each other.

In a rotary execution, the after 3 is executed, three sensors are arranged on the stator around the circumference of the rotor, wherein the sensors in the circumferential direction, although directly follow each other, but the first is spaced from the third sensor. So it is an irregular arrangement on the periphery advantageous. Direct contact between the first and third sensors would weaken the field of the adjacent permanent magnets.

Instead of of course, the three sensors on the circumference of the stator are also more sensors can be arranged. It is essential in the invention, however, that the period length p of raises and depressions on the rotor or corresponding variation of the magnetic permeability matched to the rotor is in an advantageous ratio to the distances a of the sensors. In particular, the ratio p is advantageous : a = 4: 3. In the case of a linear design, p and a are each a length value. For rotary version p and a are each an angle value.

Vorteiligerweise one of the sensors can be used as reference pulse wire, ie 0 °. Thus, the absolute number of revolutions is relative to this Reference determinable.

In the connected counter module It is advantageous not only to store the count of the sensor but also the information, which sensor last a voltage pulse has generated and supplementary which sensor before this last active sensor a voltage pulse has generated. Thus, also in the area around the reference pulse sensor always one-to-one and clear how many revolutions of the rotor in total already present.

Around to ensure a robust interaction with a fine angle sensor it is necessary that the counter module not only the number of sections determined by the reference sensor registered, the exceeded were, for example, over the interface to a higher-level control system as information available but at least the information must be provided which of the impulse wires triggered last Has. The background is that during the transition of the fine angle sensor (in the linear case fine section sensor) from 359 degrees to 1 degree not it can be ensured that the reference pulse sensor is accurate is positioned at 0 degrees and increases the count by one or decreased. Rather, with an inaccuracy of the counter of to expect a few degrees. Nevertheless, an exact number of revolutions Therefore, it is necessary to know if the reference sensor already triggered or not yet, that is the last triggering sensor the sensor was in front of the reference sensor.

Of the described speed sensor is advantageous in an electric motor integrated. Thus, with the least effort another axial Area of the rotor shaft of the electric motor executable as a speed sensor.

A fine angle sensor is additionally connectable for higher requirements, for example high-precision positioning. Advantageously, a speed sensor such as resolver In can be used for this purpose crematory encoder or an inductive encoder system.

Claims (31)

A section counter comprising a stationary part and a relatively movable part, characterized in that a first of the two parts along its the second of the two parts facing surface having alternating areas with different magnetic permeability, and that the second part such arranged permanent magnets and sensors comprising magnetic fluxes generated in the respective sensitivity ranges of the sensors, which are generated by the permanent magnets, wherein the sensors pulse-wire sensors and / or Wieganddrahtsensoren, wherein the amount and the direction of the magnetic flux in the respective sensitivity range depending on the position of the first part is so variable that signal voltage pulses can be generated by means of the sensors. section counter according to at least one of the preceding claims, characterized in that at least two magnetic circuits are formed in the second part which are also due to the alternating areas of the go first part, while during the movement of the first part of the in the sensitivity range of the Sensors trained river alternately dominated by the two circles is. section counter according to at least one of the preceding claims, characterized that the shares originating from the respective circles in the magnetic Flow in the sensitivity range of the sensor different direction and the associated Amount during the Movement of the first part varies. Section counter, full a stationary one Part and a relatively movable part, characterized, that a first of the two parts along its the second the two parts facing surface alternate areas having different magnetic permeabilities, and that the second part such arranged permanent magnets and sensors includes that in the respective sensitivity ranges of the sensors magnetic Flow is present, which is generated by the permanent magnets, in which the sensors are pulse-wire sensors and / or Wiegand-wire sensors, in which the amount and the direction of the magnetic flux in each Sensitivity range dependent is variable from the position of the first part so that means the sensors signal voltage pulses are generated, being in the second part at least two magnetic circuits are formed, which also through the alternating areas of the first Part go, while during the movement of the first part of the in the sensitivity range of the Sensors trained river alternately dominated by the two circles is whereby the shares originating from the respective circles different at the magnetic flux in the sensitivity range of the sensor Have direction and the associated Amount during the movement of the first part varies. Section counter, full a stationary one Part and a relatively movable part, characterized, that a first of the two parts along its the second the two parts facing surface alternate areas having different magnetic permeabilities, and that the second part such arranged permanent magnets and sensors includes that in the respective sensitivity ranges of the sensors magnetic Flow is present, which is generated by the permanent magnets, in which the sensors are pulse-wire sensors and / or Wiegand-wire sensors, in which the amount and the direction of the magnetic flux in each Sensitivity range dependent is variable from the position of the first part so that means the sensors signal voltage pulses are generated, the magnetic flux in the air gap perpendicular to the normal of the air-gap plane is directed. section counter according to at least one of the preceding claims, characterized that permanent magnets and sensors are connected by yokes, in particular for reducing the magnetic resistance of the permanent magnets outgoing field lines, which are due to the sensitivity ranges of Sensors go through. section counter according to at least one of the preceding claims, characterized that the direction of the magnetic flux in the respective sensitivity range depending on the position of the first part is umpolbar. section counter according to at least one of the preceding claims, characterized that the magnetic flux in the respective sensitivity range a sensor is generated by at least two permanent magnets. section counter according to at least one of the preceding claims, characterized that yokes essential for the training of circles are provided. section counter according to at least one of the preceding claims, characterized that the areas with different magnetic permeabilities than Depressions and elevations are provided. section counter according to at least one of the preceding claims, characterized that the areas with different magnetic permeabilities than ferromagnetic and non-ferromagnetic areas provided are. section counter according to at least one of the preceding claims, characterized that the signal voltage pulses of the sensors of an electronic Circuit supplied which can be supplied from the energy of these signal voltage pulses is and which is a counter for the Pulse includes, where the count non-volatile storable is. section counter according to at least one of the preceding claims, characterized that the counter as FRAM module, ie in FRAM technology. section counter according to at least one of the preceding claims, characterized that to supply the meter no external supply and no supply from other energy stores, like batteries or the like, is necessary. section counter according to at least one of the preceding claims, characterized that the counter as a single electronic component, in particular integrated Block, executed is, wherein a logic circuit and associated memory integrated in the block are. section counter according to at least one of the preceding claims, characterized that the component is supplied by a rectifier circuit, which in turn provides from the signal voltage pulses of the sensors is. section counter according to at least one of the preceding claims, characterized that the sensors work at least according to the Barkhausen effect. section counter according to at least one of the preceding claims, characterized that the meter reading Number of revolutions and / or part revolutions. section counter according to at least one of the preceding claims, characterized that with linear or rotary execution of the section counter three Sensors are provided, in particular for Wegstreckenrichtungserkennung or direction of rotation detection. section counter according to at least one of the preceding claims, characterized that the block is designed as a bus subscriber or an electrical Interface for data transmission having. Drive, comprising at least one at least a movable part and a stator comprising an electric motor, in which the stator and the movable part in a first axial area in the manner of an asynchronous motor, synchronous motor or reluctance motor is constructed, characterized in that the movable one Part in a second axial area along its the stator facing surface each other has alternating regions with different magnetic permeabilities, and that the second part, so stator, so arranged permanent magnets and sensors includes that in the respective sensitivity ranges the magnetic flux sensor is present, that of the permanent magnets is generated wherein the sensors pulse-wire sensors and / or Wieganddrahtsensoren are, where the amount and the direction of the magnetic flux in the respective sensitivity range depending on the position of the first Partly so changeable is that generated by the sensors signal voltage pulses are. Drive after at least one of the preceding Claims, characterized in that the drive and / or the electric motor constructed linear or rotary. Drive after at least one of the preceding Claims, characterized in that the axial direction in a rotary Motor is oriented in the direction of rotation axis. Drive after at least one of the preceding Claims, characterized in that the axial direction in a linear Motor is oriented perpendicular to the direction of movement. Drive after at least one of the preceding Claims, characterized in that the axial direction in a linear Motor perpendicular to the shortest Rotor-stator connecting line and / or oriented perpendicular to the orientation of the sensors, ie transverse to the direction of movement. Drive after at least one of the preceding Claims, characterized in that the stator and rotor in a third axial area a finely dissolving linear displacement sensor or a finely resolving angle sensor, so one Fine angle sensor includes. Drive after at least one of the preceding Claims, characterized in that a section counter after at least one of previous claims is arranged in the drive. Section counter, full a stationary one Part and a relatively movable part, one or more Permanent magnets and three or more impulse wires, due to a relative Movement between stationary and moving part provide electrical energy pulses, as well as a nonvolatile Counter module, thereby marked that from the counter module the information can be taken as often has triggered a definable as a reference sensor pulse wire and which pulse wire last triggered a pulse. section counter according to claim 28, characterized in that in addition the Information available can be set, which pulse wire has triggered a pulse as the penultimate. section counter according to claim 28 or 29, characterized in that the number the triggers of the reference sensor depending on the direction up or down countable are. section counter according to at least one of the claims 28 to 30, characterized in that the section counter after at least one of the claims 1 to 20 executed is.