DE10362261B4 - Electric motor - Google Patents

Abstract

Electric motor, comprising at least one stator housing (1), a rotor (2) and a fan wheel (7), the stator housing (1) comprising a B-bearing flange, the fan wheel (7) being connected to the rotor (2), wherein the fan wheel (7) is arranged axially outside the B-bearing flange, can be rotated in an area protected by a fan cover (5) and on its side facing the B-bearing flange has a receptacle on which a pole ring (11) with the fan wheel ( 7), with the electric motor having a brake (12) and with evaluation electronics (8) being arranged between the brake (12) and fan wheel (7) and sensors being connected to and arranged with the evaluation electronics (8) in such a way that the sensors are connected to the Pole ring (11) cooperate in such a way that information on the angular position and / or speed of the rotor (2) can be transmitted from the evaluation electronics (8) by means of a data line (10), or the evaluation electronics (8) are detachably connected to the B-bearing flange i st to form an electric motor without a brake (12), the B-bearing flange being intended to accommodate a B-side bearing of the rotor (2).

Description

The invention relates to an electric motor.

From the DE 199 24 201 C2 a speed sensor system is known which is particularly simple and inexpensive. The blades of a fan wheel of a motor are detected by sensors. The generated data rate is advantageously so low that an inexpensive bus system can be used to transfer the data. The disadvantage here is that the angular resolution depends on the number of fans and is therefore also limited. In addition, the sensors require a lot of space outside the engine.

The closest prior art is that DE 295 14 026 U1 , from which it is known that a proximity sensor with encoder flags is used for speed detection in an electric motor.

A frequency converter for a drive device is known from 196 22 396 A1.

From the EP 0 942 513 A2 an electric motor is known.

From the EP 1 003 268 A1 an electric lathe is known.

A polyphase electrical rotating machine is known from US 2002/0 158 523 A1.

From the U.S. 4,803,376 A a control method for an electric machine is known.

From the DE 199 26 542 A1 a connector unit for a junction box of an electric motor is known.

From the DE 695 13 089 T2 a device for angular position detection is known.

From JP H08-275 483 A, a brushless electric motor designed as an internal rotor is known.

The invention is therefore based on the object of developing a motor that is to have a robust and inexpensive encoder system.

According to the invention, the object is achieved with the electric motor according to the features specified in claim 1.

Essential features of the invention in the electric motor are that it comprises at least a stator housing, a rotor and a fan wheel,
wherein the stator housing comprises a B-bearing flange, in particular for receiving a B-side bearing of the rotor,
wherein the fan wheel is connected to the rotor, i.e. in particular rotates with the rotor,
wherein the fan wheel is arranged axially outside the B-bearing flange, is rotatable in an area protected by a fan cover and has a receptacle on its side facing the B-bearing flange, on which a pole ring is connected to the fan wheel
wherein the electric motor has a brake
and an electronic evaluation system is arranged between the brake and the fan wheel
and sensors are connected to the evaluation electronics and arranged in such a way that the sensors interact with the ring in such a way that information about the angular position of the rotor can be transmitted from the evaluation electronics by means of a data line.

The advantage here is that the resolution does not depend on the number of blades on the fan wheel, but can be selected as required. In addition, the required structural volume is much smaller and both the sensors and the evaluation electronics and the ring can be provided in a protected manner inside the fan cover.

In an advantageous embodiment, the ring has alternating magnetization on its circumference. The advantage here is that the resolution of the encoder according to the invention can be determined by means of the selection of the magnetized areas. For example are 12 or even 50 or more areas can be trained. The invention thus provides a resolution of 30 ° or even 7.2 ° or less. This is sufficient for a simple industrial positioning task. Thus, even an asynchronous motor can be used as an electric motor for positioning, that is to say it can be used in a positioning drive.

In an advantageous embodiment, the ring is a ferrite or a ferrite plastic. The sensors are then designed as Hall sensors, Wiegand wires, impulse wires or other magnetic field-sensitive sensors. The advantage here is that the sensors are insensitive to contamination and / or moisture and can be provided with temperature compensation. Power supplies can advantageously be dispensed with with Wiegand or pulse wires.

In another advantageous embodiment, the ring has alternating areas on its circumference, each of which has different values of a physical variable, in particular different values of the dielectric constant ε. The advantage here is that it causes disturbances due to the magnetic mode of operation of the motor and / or brake, have no influence on the measuring process of the sensors.

In an advantageous embodiment, the sensors are designed as field plate sensors or as other sensors that are sensitive to the values of the physical variables. The advantage here is that it is only necessary to make the values of a physical variable on the circumference variable. With the physical size, density ‘, the material can be varied accordingly. With the physical quantity dielectric constant, the material can be implemented alternately as a metal and then as an insulator. However, the density of metallic particles in a plastic matrix can also be varied.

In an advantageous embodiment, the data line runs at least partially in a hybrid cable or can be produced by modulating it onto power cables. The advantage here is that no special cable has to be laid, but rather the high-voltage cables, which have to be laid anyway, are provided with modulation devices either in a modified form as hybrid cables or in the usual form. Overall, this can be carried out in a simple and inexpensive and compact manner. In addition, the wiring is simple and robust.

In an advantageous embodiment, the evaluation electronics process the signals from the sensors in such a way that data in a bus format, such as a field bus or the like, can be transmitted via the data line. The advantage here is that the signals from the sensors do not have to be transmitted in real time, but rather the information about the angle can be transmitted in digitized form as data in fieldbus format.

In an advantageous embodiment, the data line leads to a power converter, converter and / or an electronic circuit. The advantage here is that power converters, converters and / or an electronic circuit for control and / or regulation can use the data about the angular position of the rotor and can thereby support the calculations. In particular, the control and regulation can be designed as a positioning control. The motor can even be used as an asynchronous motor, in particular in connection with an electric working brake.

In an advantageous embodiment, a converter and / or a converter is provided on the electric motor. The advantage here is that such an integrated converter or converter motor can be provided to form a compact, robust positioning drive.

Essential features of the invention in the modular system are that it comprises at least one at least two sizes, each characterized by a parameter, such as rated power, shaft height of the electric motor above the base plate, maximum torque that can be generated or the like, the electric motor each having at least one Comprises stator housing, a rotor and a fan wheel,
wherein the stator housing comprises a B-bearing flange, in particular for receiving a B-side bearing of the rotor,
wherein the fan wheel is connected to the rotor, i.e. in particular rotates with the rotor,
the fan wheel having a receptacle on its side facing the B-bearing flange, on which a ring is connected to the fan wheel,
with at least two sizes, the receptacle is designed similarly in such a way that the same ring can be provided for the respective fan wheels.

The advantage here is that only a few parts are necessary, but a large number of different electric motors, in particular different sizes, can be produced. Not only the ring but also the evaluation electronics can be used with different sizes.

In an advantageous embodiment, the motor is an electric motor with a brake, in particular with an electromagnetically actuated asynchronous motor. The advantage here is that a complete positioning drive can be implemented.

Further advantages result from the subclaims.

• In der 1 ist ein erfindungsgemäßer Elektromotor in Schnittansicht schematisch gezeichnet.
• In der 2 ist ein erfindungsgemäßer Elektromotor mit Bremse, also ein Bremsmotor, in Schnittansicht schematisch gezeichnet.

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

• In the 1 an inventive electric motor is shown schematically in a sectional view.
• In the 2 is an inventive electric motor with a brake, so a brake motor, shown schematically in sectional view.

The electric motor includes a stator housing 1 and one rotatable relative to this via two bearings 3 mounted rotor 2 . On the stator housing 1 is a terminal box 4th for connection devices attached on which a converter 6th is mounted with cooling device. The electric motor according to the invention can thus also be implemented as a converter motor. At least one thermal barrier is provided between the stator windings and the electronics of the converter or converter. The dissipation of the heat generated by the power semiconductors of the power converter or converter takes place essentially via the heat sink, whose cooling fins are in the 1 and 2 are executed to the engine. In further Embodiments according to the invention can additionally or alternatively provide cooling fins directed away from the motor. In addition, the invention also relates to pure electric motors without a converter or converter, this converter or converter being mountable in the field or in a switch cabinet and being connected to the electric motor at least with electrical supply lines.

The rotor 2 is with a fan wheel 7th releasably connected with blades, which is in one of the fan cover 5 protected area is rotatable. In particular, the fan wheel is connected to the rotor shaft of the rotor by means of a keyway connection 2 connected

On the B-bearing flange of the stator housing 1 , in particular on the side facing away from the output, i.e. on the B-side, there is an electronic evaluation system 8th releasably connected to the B-bearing flange, which includes sensors. On the fan wheel 7th is a pole ring, i.e. a ring 11 with alternating direction of magnetization on the circumference. The sensors detect the magnetic field of the ring that is rotatable relative to them and are attached to the circumference offset from one another, so that the direction of rotation can be detected. For example, if the pole ring is off 12 Areas consists of which 6th Areas with their magnetic north pole facing the sensors and 6th Areas with their magnetic south pole facing towards the sensors, the sensors are advantageously arranged offset by 15 ° on the circumference of the pole ring.

In further exemplary embodiments according to the invention, the evaluation electronics are from an electronics housing that surrounds them 9 protected. Alternatively, protection can also be achieved by overmolding or encapsulating with a plastic.

The evaluation electronics are with a data line 10 connected, which leads to the converter and feeds this information about the angle of the fan wheel. At least in those exemplary embodiments according to the invention in which the power converter or converter is mounted separately from the motor, that is to say in the field or switch cabinet, the data line can also be implemented in an integrated manner with the supply lines. To this end, a hybrid cable can be used in a first variant, which comprises power lines for supplying the motor and signal lines for data transmission and / or for the transmission of control signals. In a second variant, the data to be transmitted can be modulated onto the supply lines themselves.

In the embodiment of the invention according to 1 the evaluation electronics, including sensors and ring, are therefore compact, protected by the fan cover and the resolution is independent of the number of fan blades on the fan wheel 7th . Depending on the requirements, the ring can be designed so that not only 12 , rather 50 or more pulses per revolution can be provided.

In the 2 is a corresponding version with a brake 12 shown, with the evaluation electronics not between the B-bearing flange of the stator housing 1 and fan wheel 7th , but between brake 12 and fan wheel 7th is arranged.

The evaluation electronics can thus be used in a modular system of electric motors that includes electric motors and electric motors with brakes, as well as converter motors and converter motors with brakes. Converter motors are electric motors with an integrated converter as in the 1 and 2 shown schematically.

The ring is designed in such a way that it can be used with at least two sizes of the series, i.e. with at least two different power classes of electric motors. For this purpose, the fan wheel is designed differently in both sizes, but with the same receptacle for the ring. The same ring can therefore always be used with at least two fan impellers of the series of different sizes. Thus, the number of parts in the series is kept small overall and the storage space and costs are reduced.

In further exemplary embodiments according to the invention, the ring is connected to the fan wheel with fastening clips.

In further exemplary embodiments according to the invention, the fan wheel is made of plastic and the ring is made of ferrite or a ferrite plastic. In the latter variant, the ring is made from a plastic into which ferrite particles were mixed before the injection molding process.

In further exemplary embodiments according to the invention, the fan wheel is made from a plastic with magnetizable particles. Thus, the ring can be implemented integrated into the fan wheel, so to speak. The fan wheel is then alternately magnetized on the circumference differently, this magnetization taking place on approximately that radius on which the sensors are arranged.

In further exemplary embodiments according to the invention, the ring is not made of alternately magnetizable material, such as ferromagnet, ferrimagnet and / or permanent magnets, but a material is provided in which a physical parameter, such as electrical conductivity or dielectric constant or an electrical or magnetic susceptibility, is pronounced in varying degrees on the circumference of the ring. The sensors must then be selected accordingly. The physical parameter should preferably be varied periodically in such a way that a changed value of the parameter is assigned to each adjacent angular range and the alternation of the angular ranges can thus be detected by means of the sensors when the rotor rotates and information about the angular position and / or angular speed can thus be determined. For example, the ring can be produced from pieces of metal and plastic arranged alternately on the circumference. Field plate sensors or other sensors sensitive to electrical conductivity can thus be used as sensors.

3 shows an embodiment according to the invention again in more detail. The ring is pushed onto an elevation on the fan wheel and can be fixed with an adhesive point or an elastic and protruding plastic nose on the fan wheel. The ring also has a certain excess. The case 9 is screwed to the B-bearing flange. In other exemplary embodiments according to the invention, however, it can also be connected by gluing or riveting.

List of reference symbols

1

Stator housing

2

rotor

3

camp

4th

Terminal box

5

Fan cover

6th

Power converter with cooling device

7th

Fan wheel with blades

8th

Evaluation electronics

9

Electronics housing

10

Data line

11

ring

12

brake

Claims (17)

Electric motor, comprising at least one stator housing (1), a rotor (2) and a fan wheel (7), wherein the stator housing (1) comprises a B-bearing flange, the fan wheel (7) being connected to the rotor (2), wherein the fan wheel (7) is arranged axially outside the B-bearing flange, is rotatable in an area protected by a fan cover (5) and on its side facing the B-bearing flange has a receptacle on which a pole ring (11) with the fan wheel (7) is connected, wherein the electric motor has a brake (12) and an electronic evaluation system (8) being arranged between the brake (12) and the fan wheel (7) and sensors are connected to and arranged with the evaluation electronics (8) in such a way that the sensors interact with the pole ring (11) in such a way that the evaluation electronics (8) provide information about the angular position and / or speed of the rotor (2) by means of a data line ( 10) are transferable, or the evaluation electronics (8) being detachably connected to the B-bearing flange to form an electric motor without a brake (12), wherein the B-bearing flange is provided for receiving a B-side bearing of the rotor (2). Electric motor after Claim 1 , characterized in that the fan wheel (7) is arranged to rotate with the rotor (2). Electric motor according to one of the preceding claims, characterized in that the pole ring (11) has an alternating magnetization on its circumference. Electric motor according to one of the preceding claims, characterized in that the pole ring (11) is made of ferrite material. Electric motor according to one of the preceding claims, characterized in that the pole ring (11) is a ferrite plastic. Electric motor according to one of the preceding claims, characterized in that the sensors are designed as Hall sensors, as Wiegand or impulse wires or as other, magnetic field-sensitive sensors. Electric motor after Claim 1 , characterized in that the pole ring (11) has alternating areas on its circumference, each of which has different values of a physical variable. Electric motor after Claim 7 , the alternating areas each have different values of dielectric constant ε. Electric motor according to one of the preceding Claims 1 to 5 or 7th or 8th , characterized in that the sensors are designed as field plate sensors or as other sensors sensitive to the values of the physical variables. Electric motor according to one of the preceding claims, characterized in that the data line (10) runs at least partially in a hybrid cable or can be produced by modulating it onto power cables. Electric motor according to one of the preceding claims, characterized in that the evaluation electronics (8) process the signals from the sensors in such a way that data can be transmitted in a bus format, such as a field bus or the like, via the data line (10). Electric motor according to one of the preceding claims, characterized in that the data line (10) leads to a power converter (6), converter and / or an electronic circuit. Electric motor according to one of the preceding claims, characterized in that the electric motor can be used in a positioning drive. Electric motor according to one of the preceding claims, characterized in that the electric motor can be used for positioning an object. Electric motor according to one of the preceding claims, characterized in that the electric motor is an asynchronous motor. Electric motor according to one of the preceding claims, characterized in that the electric motor is an electric motor with an electromagnetically actuatable brake. Electric motor according to one of the preceding claims, characterized in that a converter and / or a converter (6) is provided on the electric motor.

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