DE2360182A1 - Electric motor with speed reducer - has armature mounted for rotation to permanent magnets armature shaft - Google Patents

Abstract

The electric motor has a metal casing in which two permanent field magnets are secured. The armature is mounted by journals in sintered bushes, for rotation relative to the magnets on a shaft having a screw threaded portion for meshing with a toothed wheel. A stop of plastics material engages the end face of the shaft of the armature when the motor is operating, the stop having a hexagonal cross section shank force fitted into the casing which serves to prevent rotation of the stop, and therefore acts to support the armature when it is rotating. The motor further includes a stop device in the form of a blade being operated to short circuit the armature when the operating switch of the motor is in the stop position.

Description

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Electric motor

The invention relates to a Slektroraotor with Permanent magnet and reduction gear \ in a bucket housing

from tiefgezop; enem sheet for protecting DES engine and the Wide-earth magnetic flux ..

S09-824 / 0413

The present description dier +; to Offenbai-u: ^; of the item, for a patent (or G-erauchS'.iuecer) for industrial and economic use is requested, which is in accordance with the disclosure of the inventive concept on improvements in electric motors with permanent magnets and reduction gears zuiji is used for windshield wipers in motor vehicles.

The electric motor according to the invention has a housing made of deep-drawn sheet metal, which has the following tasks: protection of the motor, transmission of the magnetic flux and fastening of the magnets that generate the flux, which are attached by means of a special adhesive tape. According to the invention, the housing does not serve as a bearing for the rotor, as is the case with conventional motors in which a closure cover or a frame is provided as a bearing, or the bearing is carried out directly on the housing. In the case of the housing according to the invention, a hexagonal opening is provided on the rear side, in which a plastic rivet with a spherical support head and hexagonal shaft is fastened by means of a press seat, the head serving as a stop for the rotor end. The hexagonal shape of the opening and the shaft serves to prevent the rivet from rotating during operation of the motor. The rivet is molded from plastic with a low coefficient of friction and high impact resistance; As a result, a low braking torque is achieved with the friction against the rotor and at the same time the noise generated by the beating axial movement of the rotor is dampened. / ^x deep-drawn

An important feature of the improvements mentioned is seen in the attachment of the magnets to the housing. So far the The magnets are attached to the housing by means of spring strips attached to the the housing has been riveted; This made the structure of the engine complicated and the cost of parts greater, so that assembly was more difficult and inefficient. According to the invention, it is proposed to thank the magnets To attach special adhesive tape that is not changed by the operating temperature and the vibrations of the engine.

The single bracket which this engine has and which is connected to the housing is formed by the connecting element from the engine to the body of the motor vehicle. The bracket is used to hold the gearwheel, which is a ^ reifi ^ into the worm of the rotor shaft and at the same time / the cut-off device ι 509824 / CK13 ^is *, _M -2-,

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included in it. The brush holder, which is made of heat-resistant, high-temperature-resistant material and serves as a guide for the brushes and for the springs that press the former against the collector, is attached directly to the holder. It is a brush holder in which three brushes are applied in the pulling direction, each of which is supported on a wall of the brush holder; the brush holder can therefore be designed with so much play that the brushes are prevented from sticking; on the other hand, the brushes are also prevented from vibrating and a corresponding reduction in annoying noise is achieved. For motors with a speed s. Only two brushes are provided, which are offset from one another by 180; on the other hand, three brushes are provided for motors with zv / ei speeds _s with only one brush holder being used in both cases _e

In order to facilitate the shaping, the brush holder housings are open at the top and are closed by a cover with three grooves for the passage of the brush feed lines »The cover has a shape that is particularly suitable for guiding the brush feed lines _? this prevents the supply lines from rubbing on the collector.

At the neck of the bracket, where the worm of the rotor shaft enters, two sintered sockets are attached with a press fit, which serve as bearings for the rotor; The shaft journals, which are located at each end of the Schneclce, are mounted in these bearings. The reason for this novel arrangement of the bearings is to be seen in the fact that the greatest transverse stresses / take place via the gearwheel of the reduction gear; it is therefore logical to place the bearings on both sides of the point from which this stress originates. The magnetic forces of attraction of the magnets on the plate pack are insignificant because the induction across the air gap is low. It is thus not necessary, v / urther bearings of the L at the other end to provide ^K uf erwell e. The advances in modern technology make it possible to achieve perfect alignment of the two lines, since both are located in the same position, so that the disadvantages associated with conventional articulation are avoided. / ^x on the runner «», «,« _Al "50_9824 / 0413

The direction of rotation of the motor is set so that the Axialk of the rotor "when a torque is delivered by the motor acts on the bracket, which is the toughest part of the engine represents, and not on the back of the case. Only the impact movements act on the plastic stop a, due to the inertia of the wiper arm and brushes are.

The end of the bracket is for receiving a screw plug provided with a thread, which is used to adjust the axial play of the rotor. Due to the delivery of a torque Considerable stresses caused by the runner, which can be traced back to the constantly increasing demands on performance are, as well as to reduce the losses due to the friction of the runner against the stop of the bracket during delivery torque, this stop is designed as a steel ball between two rolling rollers, one of which is on the shaft and the other is on the locking screw. A lubricant must also be applied to ensure proper function intended for highest pressures.

Another improvement is the union of the output shaft of the motor with the plastic gear, which engages in the snail; the union takes place here by inserting the "shaft" in the shaping of the gearwheel. The connection is released by knurling and a collar between the "two parts (wheel and shaft). The knurling takes the shaft with it, while through the federal government prevents axial displacement of the wheel relative to the shaft; thus the conventional driver plate omitted. The shaft of the gear wheel has a circumferential groove, which serves to prevent the formation of a mass consisting of burned oil; this kut is made with a lubricant, filled, which is used for additional lubrication of the bush made of sintered material serves, within which the shaft rotates. The gear that engages in the worm has a cam that controls the cut-off device of the engine; this device consists of a lamella, which during the largest part of a Rotation of the gear wheel has contact with an iris ^ menbolt and 'is lifted from this and in contact with another is brought when it is through the Mockon of the Absclialteinrichturjg is operated; in this grain L the run is switched k. \ L '«,

50982W0413 ^ _n .

* AD 'ORIGINAL

so that the engine koi-imt to a standstill. Din lamella of the defeat device is riveted to another terminal stud. Except for the three terminal bolts that are used to switch off two more are available, which are used as connection parts for the brush leads serve and carry the appropriate lines that are routed from the engine to the outside; these terminal studs are combined with this as inserts in the shaping of the shutdown plate made of thermoplastic material

Another feature of the invention is seen in the circuit for the shutdown process. The advantage over the known Circuits of this type consists in that the electrical actuation of this type of disconnection device only takes place when the control switch for the motor is in the cut-off position emotional; if no action is taken in this position, the electric motor stops in any position and cannot continue to run more continuously,

For the purpose of explaining the subject of this p is carried out below. Description with reference to the accompanying drawings and the accessories mentioned therein.

Fig. 1 shows a section of the EieWromotors. In the picture the housing made of deep-drawn sheet metal bears the reference symbol (l); The two magnets (2) are attached to the housing with special adhesive tape attached, which generate the magnetic flux. The stop on the back of the deep-drawn housing is off Plastic (3) arranged with a ball head which rests directly on the shaft of the rotor (16); this stop made of plastic has a hexagonal shank and is press fit in a hexagonal opening provided on the housing is used.

The holder (A) _t, which is connected to the housing CO, represents the connection part to the fastening plate or to the body of the motor vehicle. The brush holder (6), which holds the brushes (6), is riveted directly to the holder (4) with three pins (5). 7) and the springs (8) through which the brushes are pressed against the collector. On the neck of the holder (4) there are two sockets made of sintered material (10) in which the shaft journals (11) are mounted Ball (13) is rotatably arranged _s which

809824/0413 _ ₅ .

is freely inserted into the closure axis (14), the again has another roller (15).

A detail and a section of the brush holder are shown in Fig. 2; here the bores (17) are indicated, which are used to attach the brush holder by turning over the pins provided for this purpose on the holder; as well as the housing (18) there are, for ^Recording of the brushes and the respective springs to be recognized.

Figs. 3 and 4 show the section A-A of Fig. 1; the arrangement according to Fig. 3 applies to motors with one speed and that of Fig. 4 for two-speed motors. In the pictures are the collector (9), the cover plate (19) that closes the brush holder, the mounting holes (17), the supply lines (20) for the brushes (7), the studs (21) for the connection to the housing (l), the Holder (4) and the holder (22) for the ground connection of the common brush shown.

Fig. 5 contains another sectional view of the engine, in which shows the gear (23) which engages in the worm of the rotor shaft. This gear (23) is in the way made that the shaft (24) is used in the shaping for the gear; here are the knurling (25), a Collar (26) and a groove (27) can be seen. The shutdown plate (28) is provided with five terminal bolts (29), three of which are used for disconnection and the other two as connections for the auxiliary lines the brushes on the one hand, and on the other hand for the lines leading to the outside; with one of these terminal bolts the shut-off lamella (31) is riveted. The gear also carries the crouch (3), which the shut-off lamella (31) of the Shutdown Auto Elder Pressed.

In Figs. 6 and 7 are the electrical circuit diagrams for Single and double speed motors indicated; as can be seen from the circuit diagram, the disconnection device electrically operated only when the control switch of the motor is in the "P" position (switch-off); in Fig. 6 is the operating position of the switch with "M" and the switch-off position mi denoted "P". In both figures, the electrical circuit diagram for the motor (32) is shown with an L-ring Line as well as the actuation switch (33) for the Kotor

shown.

After a sufficient description of the subject of the invention as well as this implementation in exemplary embodiments, it is pointed out that by deviations from the above Explanations in detail the essence of the patent is not affected.

509824/04

Claims (8)

Claims 1, J Improvements in ^ electric motors with permanent magnet and ^ reduction gear, essentially characterized by that the rotor is mounted in sintered sockets on both sides of the worm, with the actual runner is arranged on the fly. 2. Improvements in electric motors with permanent magnets and reduction gears, essentially because ge ke η n ~ is characterized by the fact that the housing is made of deep-drawn sheet metal
carries magnetic flux generating magnets, which are attached with a Spsial adhesive tape. 3. Improvements in electric motors with permanent magnet and reduction gear, borrowed in the wes characterized in that a hole is provided on the back of the housing made of deep-drawn sheet metal in which there is a stop made of plastic with a spherical head and hexagonal shaft, which is directly on the rotor shaft of the Motor is present. 4. Improvements in electric motors with permanent magnets and reduction gears, essentially characterized in that that the stop located at the end of the screw is designed as a steel ball, which is located between two rolling rollers is located, one of which is arranged on the shaft and the other in the screw plug. 5. Improvements in electric motors with permanent magnets and reduction gears, essentially characterized in that only a single brush holder is used for two or three brushes lying in the pulling direction,
for motors with one speed two brushes are arranged at an angle of 180 ° and for motors with two speeds -7- 509824 / 0-13 speeds of three brushes can be provided. 6. Improvements in electric motors with permanent magnet and reduction gear, essentially characterized in that the union of the gear made of plastic, which engages in the worm, takes place with the shaft in that the shaft during the shaping process for the gear is provided as an insert, a knurling and a collar are provided to prevent uncoupling. 7. Improvements in electric motors with permanent magnets and reduction gears, essentially characterized by ge k e η η, that the housing of the brush holder are open at the top and closed by a cover with a special shape which contains three through grooves for the supply lines of the brushes, as well as the fact that the assembly with the holder wind connected by turning over pegs attached to it. 8. Improvements in electric motors with permanent magnets and reduction gears, essentially characterized by geke η η -r that the disconnection device is only electrically operated when the control switch is moved into the disconnected position. 509824/0413