WO2012041579A2

WO2012041579A2 - Armature for an electrical machine

Info

Publication number: WO2012041579A2
Application number: PCT/EP2011/063455
Authority: WO
Inventors: Gerd Kirsten
Original assignee: Robert Bosch Gmbh
Priority date: 2010-09-30
Filing date: 2011-08-04
Publication date: 2012-04-05
Also published as: DE102010041717A1; WO2012041579A3

Abstract

The invention relates to an electrical machine, especially a starter device (10) for an internal combustion engine, comprising an armature (37) having an armature winding (49). The armature winding (49) is embodied as a wave winding (212) in an armature (37) having between twelve and sixteen winding grooves (214).

Description

Description title

Anchor for an electric machine

Prior art DE 43 02 854 C1 relates to a starting device for internal combustion engines. The starting device comprises a starter motor, the drive shaft via a

One-way clutch is connected to an axially displaceable starter pinion. This spurts into the ring gear of the internal combustion engine. During a rotation, in particular in

Drive direction is responsive to a spring accumulator in the drive train between Einpurritzel and drive shaft of the starter motor, which dampens torque surges between the Einspurritzel and the drive shaft. The spring accumulator is arranged with an effective in the drive direction biasing torque in the drive train, which is 15% to 50% of the pinion rotation related short-circuit torque of Andrehmotors, the ratio of the torsional stiffness of the drive motor formed by Andrehmotor to Einspurritzel the starting device without spring and on the

Short-circuit torque related to the effective at Einpurritzel torsional stiffness of the spring accumulator> 4.

CA 2,253,169 relates to a starter device for internal combustion engines. According to this solution, a rotor is accommodated on a shaft. The rotor moves within a stator which is fixed to the inside of the housing of the electric machine. For starting internal combustion engines today usually starter devices are used in six-pole design with permanent magnets. This type of starter devices has proved to be cost effective in power ranges of 1 kW to 2 kW and in practice extremely robust and reliable. The

Winding the armature of such starter devices are performed according to the required electrical resistances in plug-in technology with two or four conductors per groove.

Presentation of the invention According to the invention is proposed due to reduced requirements for the

Cold start torque for an internal combustion engine to manufacture the armature of the starter device with a wave winding in Flyer-Wckeltechnik. To existing assemblies of the electrical machine, in particular a

Starter device for internal combustion engines, such as housings,

Brush bearing and commutator continue to use, the invention proposed, designed in flyer technology anchor is wound with a six-pole wave winding. The inventively proposed, produced in flyer technology anchor the electric machine can be installed in existing starter devices making minimal adjustments, for example, in terms of brush width.

In order to bring the inventively proposed anchor in flyer technology with respect to the required torque, taking into account the autogenous heating, in those power ranges, which have anchors that in the usual

Plug technology are designed, a new groove geometry is proposed. The Flyer anchors are generally manufactured as a four-pole version with loop winding in a 12-slot winding. This embodiment is completely symmetrical in terms of the Wckelprozesses. In this case, i. in a 12-slot winding, three slots and three teeth correspond exactly to a 90 ° angle.

In order to improve the disadvantages of a loop winding, such as low electrical resistance and thus lower heat resistance and lower torque, according to the invention a groove geometry with fourteen grooves with wave winding in six-pole design is proposed. This type of winding improves with the conventional

Wickeltechnik associated disadvantages in terms of heating occurring as well as in terms of torque formation significantly. In particular, a significant improvement in the power values can be achieved if the winding takes place in flyer technology, in particular in two winder runs with two wires in parallel winding. The two wires that are wound in parallel, for example, have a diameter of

0.95 mm per wire. This results in a significant improvement in the slot fill factor as compared to a single lap turn performed with a wire diameter of 1.4 mm. Due to the parallel winding, ie a parallel winding process, the Wckelkopf that arises in this process can be kept small, on the other hand can be due to the two parallel processed Wäcklungsdrähte smaller Diameter achieve a significant increase in the slot fill factor, that is, more copper passes into each cavity of each of the fourteen slots of the armature, which is provided in 14-groove geometry in 6-pole design with a wave winding.

The groove fill factor, also called copper fill factor, is calculated from the

Ratios of groove cross section area and copper cross section.

Short description of the drawing

With reference to the drawing, the invention will be described below in more detail. It shows:

1 shows a starter device in longitudinal section,

FIG. 2 shows the comparison of a loop winding and a wave winding,

3 shows the top view of an armature with 14-pole geometry,

4 shows the embodiment of a 6-pole Wcklung with a single wire,

Figure 5 thinner the design of a 6-pole winding with 2 wires

Diameter

FIG. 6 shows a geometry resulting from the use of a thick single wire

Winding head and a winding head geometry when using a thin single wire in two rounds,

FIG. 7 shows a standard loop winding and FIG. 8 shows a wave winding.

variants The illustration according to FIG. 1 shows a starter device in a longitudinal section. The starter device 10 has, for example, a starter motor 13 and a Vorspuraktuator 16, which may be formed for example as a relay or as a starter relay. The starter motor 13 and the electric Vorspuraktuator 16 are fixed to a common drive end plate 19. The starter motor 13 serves a

Starter pinion 22 to drive when it is meshed in a ring gear 25 of an internal combustion engine, not shown here.

The starter motor 13 has a pole tube as a housing 28, which carries on its inner circumference pole pieces 31, which are each wrapped by a field winding 34. The pole shoes 31 in turn surround an armature 37, which has an armature packet 43 constructed from fins 40 and an armature winding 49 arranged in grooves 46. The armature package 43 is pressed onto a drive shaft 44. At the end of the drive shaft 13 facing away from the starter pinion 22, a commutator 52 is further attached, which is constructed among other things from individual commutator bars 55. The commutator bars 55 are electrically connected in a known manner with the armature winding 49, that when current flows through the commutator fins 55 by carbon brushes 58, a rotational movement of the armature 37 in the pole tube 28 results. A arranged between the electric drive 16 and the starter motor 13 power supply 61, supplied in the on state, both the carbon brushes 58 and the field winding 34 with power. The drive shaft 13 is commutator side supported with a shaft journal 64 in a sliding bearing 67, which in turn is held stationary in a Kommutatorlagerdeckel 70. Of the

Commutator bearing cover 70 in turn is fastened by means of tie rods 73, which are distributed over the circumference of the pole tube 28, so for example screws, for example two, three or four pieces, in the drive bearing plate 19. It relies while the pole tube 28 am

Drive plate 19 and the Kommutatorlagerdeckel 70 on the pole tube 28th

In the drive direction, a sun gear 80 connects to the armature 37, which is part of a planetary gear, such as a planetary gear 83. The sun gear 80 is surrounded by a plurality of planet gears 86, usually three

Planet wheels 86 which are supported by means of rolling bearings 89 on journals 92. The planet wheels 86 roll in a ring gear 95, which is mounted outside in the pole tube 28. Towards the output side, the planet wheels 86 are adjoined by a planetary carrier 98, in which the axle journals 92 are received. The planet carrier 98 is in turn in an intermediate storage 101 and a slide bearing 104 arranged therein stored. The intermediate bearing 101 is designed cup-shaped, that in this both the planet carrier 98, and the planet wheels 86 are added. Furthermore, the ring gear 95 is arranged in the cup-shaped intermediate bearing 101, which is ultimately closed by a cover 107 relative to the armature 37. Also, the intermediate bearing 101 is supported with its outer circumference on the inside of the pole tube 28. The armature 37 has on the end remote from the commutator 52 end of the drive shaft 13 another

Shaft 110 on which is also included in a plain bearing 1 13. The

Slide bearing 113 in turn is in a central bore of the planet carrier 98th

added. The planet carrier 98 is integrally connected to the output shaft 1 16. The output shaft 116 is supported with its end facing away from the intermediate bearing 101 1 19 in a further bearing 122 which is fixed in the drive bearing plate 19, supported.

The output shaft 1 16 is divided into several sections: Thus, the portion which is arranged in the sliding bearing 104 of the intermediate bearing 101, a section follows with a

Spur gear 125 (internal toothing), which is part of a shaft-hub connection 128. The shaft-hub connection 128 in this case allows the axially rectilinear sliding of a driver 131. The driver 131 is a sleeve-like extension which is integrally connected to a cup-shaped outer ring 132 of the freewheel 137. The freewheel 137 (Richtgesperre) further consists of the inner ring 140 which is disposed radially within the outer ring 132. Between the inner ring 140 and the outer ring 132 clamping body 138 are arranged. The clamp bodies 138, in cooperation with the inner and outer rings, prevent relative rotation between the outer ring 132 and the inner ring 140 in a second direction. In other words, the freewheel 137 allows a circumferential relative movement between inner ring 140 and outer ring 132 in one direction only. In this embodiment, the inner ring 140 is integral with the

Andrehritzel 122 and its helical gear 143 - designed as

External helical teeth - executed. The starter pinion 22 may alternatively be designed as a straight toothed pinion. Instead of electromagnetically excited pole 31 with excitation winding 34, permanent magnetically excited poles could also be used.

The electric Vorspuraktuator 16 and its linearly movable armature 168 also has the task to move with a tension member 187 a rotatably mounted in the drive end plate lever. The lever 190 is usually designed as a fork lever and engages with two "tines" not shown here, two discs 193, 194 on its outer circumference, clamped between them Driving ring 197 to the freewheel 137 to move against the resistance of the spring 200 and thereby einzura the starter pinion 22 in the ring gear 25.

Subsequently, the Einspurmechanismus will be discussed. The electric

Vorspuraktuator 16 has a bolt 150 which is an electrical contact and in the case of Einbausein in the vehicle to the positive pole of an electric starter battery, which is not shown here in the illustration of Figure 1, is connected. The bolt 150 is passed through a lid 153. Another, second bolt 152 is a connection for the electric starter motor 13, which is supplied via the power supply 61 (thick wire). The lid 153 includes a housing 156 made of steel, which by means of several

Fasteners 159 (screws) is attached to the drive end plate 19. In the electric Vorspuraktuator 16, a pusher 160 for exerting a tensile force on the fork lever 190 and a switching device 161 is arranged. The thrust device 160 has a winding 162 and the switching device 161 a Wcklung 165. The Wcklung 162 of the thruster 160 and the Wcklung 165 of the switching device 161 each cause an electromagnetic field in the on state, which flows through various components. The shaft-hub connection 128 may take place with a

Spur gearing 125 can also be equipped with a steep thread toothing. There are the combinations possible, according to which a) the starter pinion 22 is helical and the shaft-hub connection 128 has a spur 125, b) the starter pinion 22 is helical and the shaft-hub connection 128 a

Or c) the starter pinion 22 is spur-toothed and the shaft-hub connection 128 has a helical spline. FIG. 2 shows a comparison of a loop winding and a wave winding on an armature of an electrical machine.

A loop winding 210 of the armature winding 49 of the armature shown in FIG. 2 can be formed, for example, as a 12-slot winding. North electrical poles are identified by reference numeral 202, and electric south poles by reference numeral 204. The

Forming the armature winding 49 as a loop winding 210 according to FIG. 2 represents a common embodiment of armature windings 49. In a loop winding 210, a coil is followed by another coil which lies under the same pole of the armature, while a wave winding 212 can be characterized by that - as shown in Figure 2 - on a coil, a second follows, which is below the following pole. In the case of the loop winding 210 shown in FIG. 2, a first turn 206 extends at the north pole 202 shown there, a second turn 208 at one and the same pole, ie here at the north pole 202, while the wave winding 212 according to the illustration in FIG Part of the figure, the Waklungsdraht runs in Wcklungsnuten 214 and wraps around the north pole 202 and a south pole following this 204.

The illustration according to FIG. 3 shows a plan view of a geometry of an armature, which is designed in a 14-slot anchor geometry.

The illustration according to FIG. 3 shows that, in this plan view, the armature 37, accommodated on the drive shaft 44, has individual sectors (also referred to as armature teeth), namely exactly 14, which define cavities 216 between them which define the winding grooves 214 represent.

In the case of the 14-slot geometry 220 illustrated in FIG. 3, three anchor teeth each define a pole, so that a 6-pole design of an armature having a wave winding can be realized using the 14-slot geometry illustrated in FIG. For the formation of the single poles, see in particular Figures 4 and 5 below.

In FIGS. 4 and 5, different types of wires with one thick wire or two thinner wires wound in parallel are contrasted. From the illustration according to FIG. 4 it can be seen that on a 14-groove geometry of a

Armature 37 anchor teeth 224 are formed with a thick single wire 226 wound. This results in the configuration shown in Figure 4 228, due to the high

Rigidity of the usually made of copper and provided with a paint layer thick single wire 226 relatively long builds, i. on the front sides of the armature 37 forms large Wckelköpfe due to the inherent stiffness of the thick single wire 226, see illustration of FIG. 6

From the illustration according to FIG. 4 it can be seen that in each case three anchor teeth have one

Form individual pole 224, wherein the respective outer anchor teeth of the adjacent single pole and the Wndung, which is received at the adjacent single pole 224, be enclosed. Looking at the circumference of the armature 37, in this winding pattern using a thick single wire 226, there are six poles made on a 14-groove geometry 220. In the illustration of Figure 5, the identical 14-groove geometry 220 will be referred to used the anchor 37. The pole shoes each define the winding grooves 214, in the cavities 216 of which, in this embodiment variant, individual wires 230 of a thinner diameter, for example 0.95 mm, are introduced twice wound. Similar to the illustration of Figure 4, in which a thick single wire 226 is used, can be due to the higher elasticity and the smaller diameter of the thin single wire 230, when it is wound twice, a larger number of

Accommodate windings in the cavities 216 of the individual winding grooves 214, so that the groove fill factor compared to the Waklungsvariante shown in Figure 4 is considerably larger.

This results in contrast to Figure 4, a Einzelpolaufbau 228, which adjusts itself by a much larger packing density of the thinner individual wires 230 compared to the winding of the 14-groove geometry 220 according to FIG. Also in the illustration of Figure 5 is a 6-pole version 222, i. Each three armature teeth form a single pole 224, wherein the outer armature teeth are each comprised by the Wndungen of the subsequent windings, so that six poles are formed on the circumference of the armature 37 according to the embodiment in Figure 5.

The wave winding indicated schematically in FIG. 5 is preferably produced in parallel waving runs in which two wetting wires are processed simultaneously. This favors the Nutfüllfaktor in an advantageous manner.

Figure 6 shows the designs of Wckelköpfen set when using a thicker wire and when using a thinner wire as Waklungsdraht in two rounds.

The illustration according to FIG. 6 shows that on the drive shaft 44 of the electric machine 10, in particular a starter device for a

Internal combustion engine, the disk pack 40 is located. With reference numeral 232, the size of a winding head is shown, which then adjusts when the Armature winding of a thick wire - compare illustration according to Figure 4, position 226 - is made. Due to the stiffness of the thicker winding wire, which may for example have a thickness of 1, 4 mm and more, creates a relatively long axially extending winding head - see position 232 in the left part of Figure 6. This favors the size of the starter in unfavorably, since this is as compact and

designed to be physically small and the design goal is to minimize the length of the drive shaft 44.

In contrast, in the case of the wave winding proposed according to the invention, in which o a thin individual wire 230 is installed - compare illustration according to FIG. 5 -

Winding head obtained, which has the direction indicated in the right part of Figure 6 geometry 234. Compared to the geometry 232, the Wckel head in the geometry 234 builds considerably shorter in terms of its axial length, so that on both sides of the

Wave package 40 shorter winding overhangs result, so that the length of the 5 drive shaft 44 in the embodiment using thinner

Single wires 230 with double winding circulation represents considerably cheaper, compared with the axial length of the drive shaft 44, which would set if a thicker winding wire - see Figure 4, position 226 - use would find. The Wckelkopfgeometrie shown in the right part of Figure 6, which is obtained when a o relatively thin single wire 230 having a diameter of about 0.95 mm use

In addition, in this embodiment variant, a considerably higher slot fill factor of the taper grooves 214 arises.

In the illustrations according to FIGS. 7 and 8, a standard loop winding and 5 a wave winding - compare schematic representation according to FIG. 2 - are mutually connected

compared.

In the case of the loop winding shown in FIG. 7, a single wire in a plurality of walls (compare positions 206 and 208) is connected to 0 corresponding commutator bars 55 around the same armature teeth. In

In alternating sequence, north poles 202 and south poles 204 are separated by winding grooves 214.

In the case of the embodiment of a wave winding illustrated in FIG. 8, in the five winding slots 214 which each separate a north pole 202 from a south pole 204, internal single wires introduced, which are applied in the context of a parallel winding and due to their smaller diameter in the range of less than 1 mm allow a significantly increased Nutfüllfaktor and affect the above in connection with Figure 6 axial length of the winding heads on the front sides of the disk set 40 low, and contribute in particular to the axial length of the drive shaft 44 is minimized.

In the above context, it should be mentioned that the invention

proposed wave winding 212 in 6-pole design 220 is applied to a 14-groove geometry 22 of a correspondingly configured armature 37 by means of the Flyer Wckeltechnik. In the application of the Flyer-Wckeltechnik a winding is produced by a Waklungsdraht over a roll or through a nozzle, which is located on a flyer, is supplied, which rotates at a certain distance from the carrier to be wound. The winding wire is supplied by the wave of the flyer, for example. For winding, the component to be wound is to be fixed in the Wckel area of the flyer. The flyer usually moves on a fixed circular path, which can be moved in the laying direction of the wire. The flyer winding technology has established itself as a coil Wckeltechnik that has proven especially on rotors of electric machines that have heavy stanzpaketierte sheets. The Wckeldraht is in the application of Flyer-winding technology usually over polished Leitbacken away in appropriate

Winding grooves 214, as described in the preceding figures introduced.

Claims

Electric machine, in particular starter device (10) for a

Internal combustion engine with an armature (37) having an armature winding (49), characterized in that the armature winding (49) as a wave winding (212) in an armature (37) having between twelve and sixteen Wckelnuten (214) is executed.

Electrical machine according to claim 1, characterized in that the

Wave winding (212) is wound from a thin single wire (230) with a wire diameter of <1 mm

Electrical machine according to claim 1, characterized in that the

Shaft winding (212) of the coil winding technique "Flyer-Wckeltechnik" is made twice wound.

Electrical machine according to claim 1, characterized in that a winding head (234) forming in each case on the end faces of a disk pack (40) is minimized with regard to its axial length with respect to a drive shaft (44) of the electric machine (10).

An electric machine according to claim 1, characterized in that a groove fill or copper fill factor of the winding grooves (214) is between 20% and 25%.

Electrical machine according to claim 1, characterized in that the armature (37) has in particular fourteen wedge grooves (214).

Electrical machine according to claim 1, characterized in that the

Wave winding (212) of the armature (37) in 6-pole design (222) is provided.

8. A method for producing an armature winding (49) for an electrical machine

according to one or more of claims 1 to 7, in particular one

Starter device (10) for an internal combustion engine, characterized the armature winding (49) is wound twice as a wave winding (212) of thin individual wire (230) per winding revolution.

9. The method according to claim 1, characterized in that a thin single wire (230) is wound with a diameter <1 mm.

10. The method according to claim 7, characterized in that the wave winding (212) is produced in Flyer-Wckeltechnik.