FR2633114A1 - ELECTRIC MACHINE OF THE ELECTRIC MOTOR TYPE WITHOUT MANIFOLD HAVING AN OPTICAL SENSOR - Google Patents

Abstract

The invention relates to an electric machine. In this electric machine comprising a casing, a stator and a rotor 1 comprising at least one track for producing signals, which can be optically identified, as well as an optical sensor 12, 13, 14, the latter is arranged outside the casing and at least one light guide 7, 8, 9 is provided between the area of the signal producing track 4 and the optical sensor for the transmission of optical signals. Application in particular to direct current motors without a collector.

Description

The invention relates to an electric machine comprising

  a housing, a rotor and a stator, in which the rotor

  carries at least one signal generation track, capable of

  to be identified optically and for detecting the angular position of the rotore and at least one

optical transmitter.

  Such a machine is known from the patent application

  German patent published under No. 34 18 153. This machine can be arranged in the form of a motor, for example in the form of a DC motor without collector. For obtaining switching signals for the detection of

  the angular position of the rotor, the latter contains a pis-

  te production of signals, which is explored using a sensor. The disadvantage of this type of signal formation

  must be seen in the fact that the sensor disposed close to

  The immediate momentum of the rotor is subjected, by the currents of the mo-

  tor, to intense parasitic electromagnetic fields.

  In addition, the sensor can be damaged by warming up

  the engine, but simultaneously the replacement of such a

  the engine, which is located inside an engine, also takes

a lot of time.

  This is why the invention aims to create a

  electrical machine, in which an identification is guaranteed.

  tion, insensitive to disturbances, of the

rotor.

  This problem is solved in a device of the type in-

  thanks to the fact that the optical sensor is arranged outside the housing of the electric machine and that at least

  a light guide for transmitting optical signals

  is planned between the area of the production runway

signals and the optical sensor.

  An important advantage of this solution must be seen

  in the fact that we now avoid-a disturbance of

  very sensitive electronic posing, which represents the sensor

  optical, based on the operation of the engine.

  In addition, the optical sensor can be easily replaced

  placed in the case of a defect. It is not necessary

  to access the inside of the engine.

  Another advantage should be seen in the use of light guides for the transmission of optical signals.

  As is known, the light guides are almost

  sensitive to temperature influences, and especially to

  A-vis parasitic electromagnetic field.

  According to an alternative embodiment of the invention,

  is proposed to integrate the optical sensor in an electronic circuit

  order. This electrical control circuit is

  particularly necessary in the case of a motor with con-

  tinu for controlling the different motor windings

  and contains the entire electronic control system.

  An integration of the optical sensor has the advantage of

  that the sensor signals can be

  directly to the control circuit and without any additional transmission lines. Such control circuits are protected in general by means of a box vis-à-vis

  dust and other atmospheric influences. This if

  that the same protection provisions apply

also to the optical sensor.

  According to an alternative embodiment, the light guide may be equipped with a plugging device. This plugging device is intended to arrange the end of the light guide, turned towards the signal production track, so as to allow it to be plugged into the motor housing. For this purpose, a corresponding receiver device is provided on the motor housing. This plug-in connection has the further advantage that the motor can be very easily separated from the electrical control circuit, for example when replacing the motor or the control circuit or when replacing the light guides. themselves. It is also possible to arrange this plug-in device for several light guides so that it suffices to use a single connector for a multiplicity

transmission lines.

  According to another embodiment of the invention,

  it is proposed to equip the light guide with a head

  flex. This has the advantage that the transmission of light from the light source to the track of

  signals are produced by means of the gui-

  of light. This light is reflected on the track of

  signal production and reflected radiation is also

  sent using the light guide to the optical sensor.

  The signal generation track is suitably formed of a sheet of plastic material fixed on the front face of the rotor. Reflective surface areas and non-reflective surface areas are provided

  on this plastic sheet.

  Advantageously, these superficial zones are distributed

  depending on the distribution of the rotor poles ,.

  that is to say that the optical sensor is sent a signal form, which is identical to the angular position of the poles of the rotor, so that the switching signals can be drawn directly from the signals received, to achieve the

engine control.

  The production of the optical signal is carried out, for example

  by means of a light signal generator, which is also

  located in the electrical control circuit. The signal

  light is sent, by means of what is called a cou-

  cry Y, at the reflex head of the light guide. As a general

  light signals, a light diode can be used.

  nescence. The invention will be explained hereinafter more

  detailed with reference to an exemplary embodiment.

  Figure 1 shows a schematic representation of a

  device for identifying the position of the rotor.

  Figure 2 shows a schematic representation of a

  rotor having a signal generation track.

  Figure 3 shows a partial view of a motor

  carrying a plug-in light guide.

  The rotor 1 of an engine, for example a motor with

  Continuous reactor without collector is shown in FIG. 1. This rotor 1 carries a plurality of permanent magnets on a wire.

  2. These permanent magnets 3 are arranged with

  alternating larities and with a direction of radial magnetization

  the, on the shaft 2 so as to form a rotor having three pairs of poles. A signal generation track consisting of zones 5a, b, c reflecting the light and zones 6a, b, c not reflecting the light is located on the front face 4 of the rotor 1. The distribution of the zones is chosen from way that they correspond to

  the distribution of the poles of the permanent magnets 3. To

  to detect the angular position of the rotor, three light guides 7,8,9 are provided, the ends of which are directed

  to track 4 signal production. These guides to

  7,8,9 are fixed for example on the housing, not shown.

  here, from the rotor. The light guides 7,8,9 comprise reflex heads, at their ends facing the signal production track. This means that each light guide simultaneously emits a light signal and

  that the light reflected by the production track of

  is received again. The light guides 7,8,9 penetrates

  trent in a housing 10, in which three optical sensors 12,13,14 and three signal generators 15a, b, c

  are arranged on a plate 11. This casing contains, for example,

  also a control circuit necessary for the control of the motor. Each of the light guides 7, 8, 9 is constituted by a multiplicity of light guides

  thin individuals, who are brought together to form a

  CWater. The injection by coupling of the light, which is pro-

  by light signal generators 15a, b, c, is

  through so-called Y-couplers, that is to say, part of the various

  light 7,8,9 is connected to the light signal generator.

  15a, b, c. The other part of the light guides is

  corded to the respective optical sensors 12,13,14. As a result

  the transmission of light to the mirror head of the light guide

  of respective light is made using a portion of the individual light guides. The other part of the individual light guides ensures the transmission of light, reflected on the signal transmission track 4, on the

  respective optical sensors. The signals received by the

  12,13,14 can be used both for

  determine the rotational speed of rotor 1 only to determine

  undermine its angular position. The identification of the position

  angle of the rotor is necessary for example for the control

  of, without collector, motor coils. It is visible

  in this figure 1 that no electronic component is dis-

  placed on the rotor and therefore in close proximity to the magnetic fields of the permanent magnets and the motor coils, not shown here. All componentstelsque

  the sensors, the light sources, are located outside

  the engine in a crankcase 10. Therefore this ex-

  any damage to these electronic components, due to spurious fields, vibrations or

temperature.

  In Figure 2, there is shown in a schematic representation, another variant of a rotor having a signal generation track. The constitution of the rotor 16

  is identical to that of the rotor shown in Figure 1.

  Only the signal generation track 17 has a structure

  slightly modified. This track 17 of production of

  There are three individual tracks 18,19,20. A guide

  of light 21,22,23 is associated with each of these tracks indi-

  dividuelles. These light guides 21,22,23 are located side-

  side-by-side in the radial direction and can therefore be gathered in a compact manner in a single housing 24. The light guides 21, 22, 23 are also

  connected to a boot mill not shown here, in which

  optical sensors and a light signal generator

nous.

  The schematic representation of Figure 2 is

  produced, in Figure 3, in the form of a partial view of a motor, in a sectional representation. The rotor 16

  is rotated so that it can rotate, through

  a shaft 25 and ball bearings 26, in a housing 27 of the engine. Corresponding coils 28,29 of the motor are located on the housing 27 of the engine. These coils form the stator of the motor. A recess 30 is provided in the housing 27 of the engine. The housing 24 of the light guides 21,22,23 is located in this recess 30. The housing 24 is designed as a removable plug-in connector,

  which is fixed in the recess 30, so that it is possible to

  read as well a simple mounting of the light guides on

  the motor a simple replacement of the light guides.

  The light guides 21, 22, 23 have the reflection heads 31, 32, 33, which are directed towards a production track 17

  of signals. This signal generation track 17 is

  attached to the rotor 16 and comprises the individual tracks 18,

  19,20, shown in Figure 2. Naturally, on the

  this of the three light guides indicated in the description,

  it is also possible to provide several light guides. The combination of the ends, located on the motor side, light guides in a housing 24 is advantageous in all cases, since this common stack greatly facilitates the assembly and replacement of the entire beam of

light guides.

Claims (8)

  Electrical machine comprising a housing, a rotor and a stator, in which the rotor comprises at least one signal generation track, which can be identified optically and used to detect the angular position of the rotor.   rotor, and at least one optical sensor is provided.   the optical sensor (12, 13, 14) is disposed outside the housing of the electric machine and at least one light guide (7, 8, 9) for transmitting optical signals is provided between the region of the signal generation track (4) and the optical sensor (12,13,14).   2. Electrical machine according to claim 1,   characterized in that an electrical control circuit is provided outside the housing and that the optical sensor (12,   13, 14) is disposed within the control circuit.   3. Electrical machine according to claim 2, characterized   characterized in that the light guide (21,22,23) comprises, at its end facing the signal generation track (17), a plug-in device and that the housing (27) has a recess ( 30) for connecting   removably the light guide to the housing (27).   4. Electrical machine according to claim 3, characterized   characterized in that several light guides (21, 22, 23)   carry a single plug-in device (24).   5. Electrical machine according to any one of the   1 to 4, characterized in that the guide to   (21,22,23) has, on its end turned towards   the signal generation track (4, 17), a head flex.   6. Electric machine according to any one of the   Claims 1 to 5, characterized in that the signal generation track (4, 17) consists of a sheet of plastics material, which is fixed on a front face   rotor (1,16), the optical signals being produced at   yen of superficial areas (5,6) with different reflections.   7. Electric machine according to any one of the   Claims 1 to 6, characterized in that the subdivision of the surface areas (5, 6) with different reflections corresponds to the subdivision of the rotor poles (1, 16).   8. Electric machine according to any one of the   Claims 1 to 7, characterized in that a generator is provided inside the electrical control circuit   light signals (15) for introducing a light signal.   in the optical guide (7,8,9).