DE102011001347A1 - Direct current electromotor for use with drive motor in e.g. interior of door, for window lifter in car, has rotor comprising cavities, and brushes pressed against collector/commutator in radial directions and spaced at specific angle - Google Patents

Abstract

The electromotor (10) has a connector element provided for a power source, and a cover (19) for a retaining housing (11). A stator body comprises a tubular shaped magnet, which is magnetized at four poles, where each section of the poles is in the form of a circular edge. An angle of the circular edge is about 90 degrees, and a rotor (13) has 9 cavities. Brushes (16) are pressed against a collector/commutator in radial directions and spaced at an angle of about 80 degrees. The tubular shaped magnet is arranged in the housing.

Description

The invention relates to an improved DC electric motor, in particular for geared motors for windows, seats, windscreen wipers and other applications in vehicles.

Known and widely used today are electric motors with associated reduction gear for use, for example, in motor vehicles for moving window regulators, windscreen wipers, seat parts and the like, which are characterized mainly by their compactness.

Such electric motors are in fact suitable for installation in narrow spaces, such as the interior of a door or the trunk lid or the hood of a vehicle.

In view of increasing customer demand for vehicles, eg. As automobiles, SUVs, but also watercraft, with servo devices such. As window regulators, seats, windshield wipers and the like are equipped, and in view of the ever-increasing demand for such compact electric motors is more and more in this area the need to automate the production of such compact electric motors in order to quickly as possible to the rapid change of Market while keeping costs at a competitive level.

The quest for increased automation of manufacturing is associated with the simplification and standardization of component production, which is not only aimed at faster assembly, but also at specifying the manufacture of engines that are ready for use in vehicles of different manufacturers and the in turn different standards, eg. B. in the control of the movement of the electric motor.

Nowadays, the reading of the position, velocity and acceleration of a drive shaft of a DC electric motor to be installed in a motor vehicle usually takes place with an incremental device in which an electronic control unit detects a zero point (upon reaching and recognizing a stop) and at this zero point a first calibration executes so that starting from this zero point, the electronics by counting the pulses that it receives from a sensor disposed in the engine and the drive shaft facing sensor can detect and evaluate the movements of the drive shaft.

Particularly common in electric motors for such applications are the digital sensors known as "Hall-effect sensors".

When such sensors are used, the electronics detect a series of 1/0 transitions, and from the counting of them, they extract the information about the position, speed and acceleration of the drive shaft and thus the associated drives.

Further, the possibility is known to perform the survey of the parameters of the drive shaft rotation without resorting to Hall sensors by the electronics for reading the analog feed signal is formed.

In particular, the electronics for counting the so-called "commutation ripples" or the voltage peaks formed, which go back to the commutation between brush and collector.

However, in order to be readable by the control electronics, a corresponding analog signal must have a low noise level well filterable by the electronics, with pulse levels (the voltage spikes at commutation) of sufficient energy to be well recognized by the electronics. In this way, the analog signal is comparable to a digital signal and as such calculable.

To achieve this, there must be a stable balance in the contact between brush and collector / commutator.

Each vehicle manufacturer uses its own dedicated electronic control unit, and the design of an electronics unit that processes an analogue signal, such as the "ripple" signal, requires a different development than an electronic system that processes a digital signal, like that of a Hall sensor detected signal is.

Object of the present invention is to provide an improved DC electric motor, in particular for gear motors for windows, seats, windscreen wipers and the like, which has a better stable balance of contact zones between the brush and collector and at the same time by automated or semi-automated operations to manufacture, the standardization of the components and the structural changes that are preferred to allow for its automated production, generally do not affect its performance and, in particular, do not limit the ability to detect the rotational movement of the drive shaft in an optimal manner in an analogous way.

In the context of this object, an improved electric motor is provided, which can be used with known reduction gears, without special changes have to be made to these.

Within the scope of this object, a DC electric motor is provided which can be controlled both by means of an analog signal and by means of a digital signal and is no less powerful than similar known electric motors.

Finally, a DC electric motor, in particular for moving z. B. of window regulators, seats, windscreen wipers and the like in motor vehicles, which can be realized with known systems and techniques.

• – der Statorkörper aus einem rohrförmigen Magneten besteht, der an vier Polen magnetisiert ist, von denen jeder einen Schnitt in Form eines kreisförmigen Bogens hat, wobei der Bogen eine Winkelweite von 90° hat,
• – der Rotor neun Hohlräume aufweist,
• – zwei Bürsten vorhanden sind, die in radialen Richtungen, die in einem Winkel von 80° beabstandet sind, gegen den Kollektor/Kommutator gedrückt sind.

These and other objects, which will become more apparent hereinafter, are achieved by an improved DC electric motor, especially for geared motors for power windows, seats, windscreen wipers and other similar applications in vehicles, comprising a stator housing housing and a rotor having a drive shaft comprising a housing Collector / commutator, corresponding brushes for the collector / commutator carries, further comprising a connector element for the power supply of the motor, a closure cover for the housing, characterized in that

• The stator body consists of a tubular magnet magnetised on four poles, each of which has a section in the form of a circular arc, the arc having an angular extent of 90 °,
• The rotor has nine cavities,
• - There are two brushes, which are pressed in radial directions, which are at an angle of 80 °, against the collector / commutator.

Other features and advantages of the invention will be more fully apparent from the description of three preferred embodiments of the improved DC electric motor of the present invention, which are illustrated by way of non-limitative example in the accompanying drawings. Show it

1 a partially exploded perspective view of the electric motor according to the invention in a first embodiment,

2 a side view of the electric motor of 1 .

3 the section on the section line III-III of 2 .

4 a part of an exploded view of the electric motor according to the invention in its first embodiment,

5 a partially sectioned side view of the electric motor according to the invention,

6 an exploded perspective view of an electric motor according to the invention in a second embodiment,

7 a partially sectioned side view of the electric motor of 6 .

8th a further exploded perspective view of the engine in its second embodiment, and

9 an exploded perspective view of the electric motor according to the invention in a third embodiment.

In his in the 1 to 5 The first embodiment shown is an improved DC electric motor according to the invention, in particular for geared motors for window regulators, seats, windscreen wipers and other applications in vehicles as a whole with the reference numeral 10 designated.

The electric motor 10 includes a receiving housing 11 for a stator body 12 and for a rotor 13 with a drive shaft 14 with collector / commutator 15 and brushes 16 and 17 , All the above elements are in the sectional view of 3 clearly visible.

The electric motor 10 further comprises a connector element 18 for powering the motor and a cap 19 for the housing 11 ,

• – der Statorkörper 12 von einem rohrförmigen Magneten 20 gebildet ist, der mit vier Polen magnetisiert ist, wobei jeder dieser Pole einen Schnitt in Form eines kreisförmigen Bogens hat, wobei der Bogen eine Winkelbreite von 90° hat,
• – der Rotor 13 neun Hohlräume 21 hat,
• – zwei Bürsten 16 und 17 vorhanden sind, die in radialen Richtungen in einem Winkelabstand A von im Wesentlichen 80° gegen den Kollektor/Kommutator 15 gedrückt sind.

The peculiarity of the electric motor according to the invention 10 lies in that

• - the stator body 12 from a tubular magnet 20 which is magnetized with four poles, each of these poles having a section in the form of a circular arc, the arc having an angular width of 90 °,
• - the rotor 13 nine cavities 21 Has,
• - two brushes 16 and 17 present in the radial directions at an angular distance A of substantially 80 ° to the collector / commutator 15 are pressed.

Of the four poles are in the 3 two shown, with a first pole (north pole) with 20a and a second pole (south pole) with 20b is designated.

The shape of the stator 12 , a tubular magnet, its four poles, a rotor 13 with nine cavities 21 and the position of the brushes, which are spaced 80 ° apart, allow the best possible Commutation "ripple" for this type of electric motor to realize.

In this first embodiment of the electric motor according to the invention 10 is the body 22 of the connector element 18 designed so that it partially with a movement in the direction parallel to the drive axis in a recess 26 on the body of the lid 19 and with quick-latching, z. B. two matching teeth 24 and 25 of which at least one is elastically deformable, is to be fastened there.

The body 22 of the connector element 19 has receiving seats for electronic components that detect an analog signal of movement of the drive shaft.

In this embodiment, a first seat 27 for a Hall sensor 28 which interacts with one on the drive shaft 14 pressed cylindrical magnet 29 is provided, and a second seat (not visible in the drawings) for a passive element 30 for the connections 31 provided for the transmission of the signals and the supply.

The directly on the body of the connector element 18 trained seat 27 for the Hall sensor 28 allows the Hall sensor quickly and economically without the interposition of other pre-assembly serving recordings on the electric motor 10 while maintaining its correct position relative to the cylindrical magnet 29 sure.

The brushes 16 and 17 are each in appropriate seats 32 respectively. 33 with a radial course on the lid 19 assembled.

These seats can either be integral with the lid or on separate and later mounted on the lid components.

In a brush motor, the angular position of the brushes that produces the maximum electrical efficiency is the one that mimics the magnetic division.

With four magnetic poles, each with an angle of 90 °, this results in the maximum power with 90 ° between the brushes.

In a motor with permanent magnets, the vibration and thus the noise, which is a very important parameter for the evaluation of the quality of an electric motor for power window or seat adjustment devices, the lower the more constant during the 360 ° of rotation of the rotor by the interaction of Stator and rotor generated torque is because each torque peak generates vibrations and accelerations.

In a brush electric motor designed for compactness, these vibration / noise effects increase, either because of the smaller number of cavities and poles, or because of the decision to use permanent magnets with better magnetic properties.

To reduce vibration and noise, the best combination results when the difference between the number of poles of the stator and the number of cavities of the rotor is a prime number and therefore no simultaneity of input and output between the homologous points of the pole pieces of the rotor and the Magnetic poles of the stator is present.

A further improvement in this sense is given by the use of the tubular and one-piece stator body, since in this way no "violent" interaction of forces between the edges of the pole pieces of the rotor and the edges of the magnetic poles is generated, precisely because physically the magnetic poles of four separate bricks are produced, each with its edges creating a non-constant air gap, but because the magnetic poles are created by magnetizing a single tubular element defining a constant air gap.

The described solution of the invention with four in a tubular magnet 20 generated magnetic poles and nine pole shoes 21a or nine cavities 21 of the rotor 13 Realizes such a state of minimal vibration.

However, in order to optimize the ripple signal, the concurrency of the commutation is required to double the voltage / current peak, and therefore the angular position is preferred in which the angle between the brushes is 80 °.

The tubular magnet 20 is in interference fit in the housing 11 arranged.

Alternatively, the tubular magnet is arranged in clearance. This solution could generate, within the tolerances, unpleasant vibrations and noises when the tubular magnet is beaten against the housing.

The clearance thus requires the additional use of fasteners. One way to, even partial, attachment consists in a bond. Bonding, however, is a process that slows down the productivity of automated manufacturing equipment.

Therefore, the attachment of the tubular magnet in the seat is preferably carried out by such cooperation of mechanical means and partial bonding that the mechanical means keep the tubular magnet in the seat and in position, as long as the adhesive z. B. does not reach 100% of its effectiveness.

Alternatively, the permanent magnet 20 only with mechanical anti-rotation means on the housing 11 established.

The rotation of the tubular magnet 20 inside the case 11 is achieved by using z. B. an anti-rotation ring 35 prevents the excess with in the housing 11 is arranged and by means of a tooth or more teeth 36 that of the ring 35 go out and engage in correspondingly shaped recesses 37 on the magnet 20 are suitable, in the axial direction of the tubular magnet 20 is plugged.

At the bottom side of the housing 11 is the tubular magnet 20 by a connection between one on the inside of the housing 11 protruding tooth 38 and a second recess 39 at the bottom of the tubular magnet 20 held.

The 6 to 8th show an improved DC electric motor according to the invention, in a second embodiment, in total with the reference numeral 110 is designated.

In this second embodiment, the lid 119 shaped so that he has an electronics card 140 covers and receives, in turn, with the connector element 118 connected is.

This electronic card 140 carries on one side, the inside of the case 11 facing, the brushes 116 , which are spaced apart by an angle of 80 °, and on the other side a Hall sensor 28 for insertion into a corresponding, suitably shaped seat 127 is provided, which receives him and maintains the correct position and in the lid 119 the cylindrical magnet 129 is formed facing.

The annular magnet 120 , which forms the stator body, has a first upper recess 137 for a corresponding one of the anti-rotation ring 135 protruding tooth and a second lower recess 139 for the tooth 138 at the bottom of the case 111 ,

The brushes 116 are inserted into corresponding radially extending chambers and are pressed by one end of a corresponding coil spring, or they are mounted on elastic supports with leaf springs or carried by other similar and equivalent devices and pressed.

In a third embodiment of the improved DC electric motor according to the invention, which in the exploded view of 9 shown and there by the reference numeral 210 is designated, the anti-rotation means consist of a tooth 235 from the bottom edge of a tubular section 250 protrudes, extending from the lid 219 to the interior of the case 211 extended, with the tooth 235 for engaging in a corresponding first upper recess 237 at the top of the tubular magnet 220 is provided.

The tubular magnet 220 also has a second lower recess 239 for the tooth 238 at the bottom of the case 211 on.

The improved DC electric motor according to the invention 10 . 110 and 210 may be a motor with straight, ie according to a rectilinear path with a direction parallel to the axis of rotation extending rotor cavities or with inclined, ie running on an inclined path rotor cavities.

Accordingly, the inventive improved DC electric motor 10 . 110 and 210 a tubular magnet 20 . 120 and 220 with straight, that is, according to a rectilinear path with a direction parallel to the axis of rotation extending poles or with inclined, ie extending on an oblique path poles.

In practice, it has been shown how the invention fulfills the stated tasks.

In particular, the invention provides an improved DC electric motor, in particular for power window motors, seats, windscreen wipers and the like, which has a better stable balance of contact zones between the brush and collector and which is to be manufactured simultaneously by automated or semi-automated operations, the Standardization of the components and the structural changes that are preferred to enable its automated production, generally do not affect its performance and in particular do not limit the ability to detect the rotational movement of the drive shaft in an optimal manner in an analogous way.

In addition, with the invention, an improved electric motor has been realized, which can be used with known reduction gears, without special changes to these must be made.

Furthermore, the invention specifies a DC electric motor which can be controlled both by means of an analog signal and by means of a digital signal and is no less powerful than similar known electric motors and therefore adaptable to the various internal standards of the vehicle manufacturer.

Finally, with the invention, a DC electric motor, in particular for moving z. Example of window regulators, seats, windscreen wipers and the like in motor vehicles, which can be realized with known systems and techniques.

Numerous modifications and variations of the invention thus conceived are possible, all of which are within the scope of the inventive concept. In addition, all details can be replaced by other, technically equivalent elements.

In practice, the materials used as well as the dimensions and shapes are arbitrary depending on the requirements and the state of the art.

Whereuper reference numerals follow a property or technique in the appended claims, such reference numerals are merely for the better understanding of the claims, and thus have no limiting effect on the interpretation of any element exemplified by such reference numerals.

Claims (9)

Improved DC electric motor ( 10 ), in particular for gear motors for windows, seats, windscreen wipers and similar applications in vehicles, comprising a receiving housing ( 11 ) for a stator body ( 12 ) and for a rotor ( 13 ) with a drive shaft ( 14 ) with collector / commutator ( 15 ) and brushes ( 16 . 17 ), characterized in that it further comprises a connector element ( 18 ) for the power supply of the motor, he a closure cover ( 19 ) for the housing, wherein the stator body ( 12 ) from a tubular magnet ( 20 ) magnetized at four poles, each of which has a section in the form of a circular arc, the arc having an angular width of 90 °, the rotor ( 13 ) nine cavities ( 21 ) has two brushes ( 16 . 17 ) which are pressed against the collector / commutator in radial directions spaced at an angle (A) of substantially 80 °. An improved DC electric motor according to claim 1, characterized in that the body ( 22 ) of the connector element ( 18 ) for partially inserting and fastening by means of quick-latching means in a recess ( 26 ) on the body of the lid ( 19 ) suitable is. Motor according to the preceding claims, characterized in that the body ( 22 ) of the connector element ( 18 ) Receiving seats for electronic components, which is used to raise an analogue motion signal of the drive shaft ( 14 ) are provided. Motor according to the preceding claims, characterized in that the brushes ( 16 . 17 ) on the lid ( 19 ) each in a corresponding seat ( 32 . 33 ) are mounted with a radial course. Motor according to the preceding claims, characterized in that the tubular magnet ( 20 ) in the housing ( 11 ) is arranged in interference fit with this. Motor according to claims 1 to 4, characterized in that the tubular magnet ( 20 ) is inserted with play in the housing and with mechanical anti-rotation means on the housing ( 11 ). Motor according to the preceding claims, characterized in that the anti-rotation means consist of an anti-rotation ring ( 35 ), which are oversized in the housing ( 11 ) and by means of one or more teeth ( 36 ) in the axial direction on the tubular magnet ( 20 ), which is from the ring ( 35 ) and for engaging in appropriately shaped recesses ( 37 ) on the magnet ( 20 ), wherein the tubular magnet ( 20 ) from the side of the bottom of the housing ( 11 ) of a connection between one on the inside of the housing ( 11 ) protruding tooth ( 38 ) and a second recess ( 39 ) at the bottom of the tubular magnet ( 20 ) is held. Motor according to claims 1 and 6, characterized in that the cover ( 119 ) is shaped so that it has an electronic card ( 140 ) and which, in turn, engage with the connector element ( 118 ), the electronic board ( 140 ) the brushes spaced apart by 80 ° ( 116 ) and at least one Hall sensor ( 128 ), which is suitable for insertion into a corresponding suitably shaped seat ( 127 ) for picking up and maintaining the correct operating position of the cylindrical magnet ( 129 ) facing the lid ( 119 ), is suitable. An improved DC motor according to claims 1, 6 and 8, characterized in that the anti-rotation means from a tooth ( 235 ) extending from the lower edge of a tubular section ( 250 ) protruding from the lid ( 210 ) to the interior of the housing ( 211 ), whereby the tooth ( 235 ) for engaging in a corresponding first upper recess ( 237 ) at the upper edge of the tubular magnet ( 220 ) is suitable, and from a second lower recess ( 239 ) at the bottom of the tubular magnet ( 220 ) for a tooth ( 238 ) at the bottom of the housing ( 211 ) consist.

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