EP2559046A1

EP2559046A1 - Starting apparatus having an electromagnetic switch, and method for switching the electromagnetic switch

Info

Publication number: EP2559046A1
Application number: EP11714336A
Authority: EP
Inventors: Houman Ramezanian; Claus Kramer; Michael Froehlich-Schlapp
Original assignee: Robert Bosch GmbH
Current assignee: Robert Bosch GmbH
Priority date: 2010-04-15
Filing date: 2011-04-15
Publication date: 2013-02-20
Anticipated expiration: 2031-04-15
Also published as: PL2559046T3; WO2011128442A1; EP2559046B1; DE102010027823A1

Abstract

A starting apparatus having an electromagnetic switch (16), having two contacts (180, 181), which can be electrically conductively connected to one another by means of a moving contact link (184), wherein at least one of the two contacts (180, 181) has a contact surface (300) which is connected to a contact bolt (150, 151), wherein the contact surface (300) has projections with a corrugated contour (303), characterized in that they essentially lie on a plane and the contact link (184) has an outer flat section (276), wherein, in one switch position, the outer flat section (276) of the contact link (184) slides or rubs on a section of the corrugated contour (303), whose surface faces away from a central axis (315) of the switch (16), wherein the corrugated contour (303) is part of an annular groove system (310), and a current transmission surface (500) between the surface (318) and the contact surface (300) is in the form of a sickle. A method for switching an electromagnetic switch of a starting apparatus (10), having two contacts (180, 181) which are electrically conductively connected to one another by means of a moving contact link (184), wherein, when the contact link (184) makes contact with at least one of the two contacts (180, 181), a rubbing movement acts between the contact link (184) and a contact surface (300) of the at least one contact (180, 181), wherein the contact surface (300) has projections which essentially lie on a plane, and the contact link (184) has an outer flat section (276), wherein, in one switch position, the outer flat section (276) of the contact link (184) slides or rubs on a section of the corrugated contour (303) which faces away from a central axis (315) of the switch (16), wherein, when sliding, a surface (318) adjusts a current transmission surface (500), which is in the form of a sickle, via the contact surface (300).

Description

Description title

Starting device with an electromagnetic switch and method for switching the electromagnetic switch

State of the art

The invention relates to a starting device with an electromagnetic switch and a method for operating the electromagnetic switch.

From the German patent application DE 195 49 179 AI is a

electromagnetic switch (engagement relay) for a starting device known. This switch has two contacts, which are referred to there as contact pins. Both contacts are electrically conductively connected to each other by a movable contact bridge to supply current from the contact pin, which is connected to a positive pole of a starter battery, to a contact pin

forward and thereby electrical potential to a starter motor, which is not shown there, to lead. From DE 10 2004 017 160 AI another relay for starting devices is known. This relay has a so-called self-resilient contact bridge, in which after the contact between the contact bridge and the mating contacts by the elasticity of the contact bridge, a transverse force between the contact bridge and their

Surface and the mating contacts arises.

In contrast, the contact between contact bridge and

Counter contacts are further improved.

Disclosure of the invention The proposed solution seeks to create a scraping movement between the two contact surfaces between the contact surface of the contacts and the surface of the contact bridge and thereby contamination and other by the

To remove switching movement.

Short descriptions of the drawings

The invention will be explained in more detail below by way of example with reference to the figures, in which:

FIG. 1 shows a starting device in a longitudinal section,

2 shows a longitudinal section through the electromagnetic switch according to a first embodiment,

FIG. 3 shows a side view of a contact bridge,

FIG. 4 is a plan view of a contact bridge;

Figure 5 shows three different cross-sections of the contact bridge according to the first

Embodiment of Figures 3 and 4,

FIG. 6 shows a plan view of the contact of a bolt,

FIG. 7 is a sectional view of a contact of a bolt according to FIG. 6,

FIG. 8 shows a side view of a contact pin 151 and a contact bridge according to a second exemplary embodiment,

FIG. 9 shows a second side view of the second exemplary embodiment according to FIG. 8,

FIG. 10 is a side view of a third embodiment,

Figure 11 shows a fourth embodiment of a switch with another

Position of the contact bridge,

Figure 12 in principle a fifth embodiment as a modification of

Embodiment of Figure 2,

13 shows a sixth embodiment of a pairing of contact pins with a contact bridge, FIG.

FIG. 14 shows a seventh exemplary embodiment of a pairing of contact bridge and contact pin, FIG. 15 shows an eighth exemplary embodiment of a pairing of a contact bridge and two contact pins,

FIG. 16 and FIG. 17 each show an alternative embodiment of a contact bridge,

FIG. 18 and FIG. 19 two further alternatives for contact bridges,

FIG. 20 shows a sectional illustration of a principle shown here

Contact Bridge,

FIG. 21A shows a side view or sectional view of a further particularly advantageous combination of contact bridge and contact surface,

Figure 21B is a view of a current transfer surface between contact bridge and

Contact,

FIG. 21C shows a side view or sectional view of a further advantageous combination of contact bridge and contact surface,

FIG. 22A is a diagram showing dependencies of various parameters.

FIG. 22B shows a half contact bridge with different dimensions, which are important for FIG. 21A.

Embodiments of the invention

FIG. 1 shows a starting device in a longitudinal section. FIG. 1 shows a starting device 10. This starting device 10 has, for example, a starter motor 13 and an electromagnetic switch 16, which is designed here as an engagement relay. The starter motor 13 and the switch 16 are fixed to a common drive end plate 19. The starter motor 13 is functionally to drive a starter pinion 22 when it is meshed in the ring gear 25 of the internal combustion engine, not shown here. The starter motor 13 has a housing as a pole tube 28 which at its

Inner circumference carries pole pieces 31, which are each wrapped by a field winding 34. Instead of an electrical excitement comes one

Permanent magnetic excitation of the stator in question. 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 44 facing away from the starter pinion 22, a commutator 52 is further attached, which is constructed, inter alia, of individual commutator fins 55. The commutator bars 55 are electrically connected in a known manner with the armature winding 49, that when energized

Commutator blades 55 by carbon brushes 58 results in a rotational movement of the armature 37 in the pole tube 28. One between the Einspurrelais 16 and the

Starter motor 13 arranged power supply 61 supplies in the on state, both the carbon brushes 58 and the field winding 34 with power. The drive shaft 44 is commutator side with a shaft journal 64 in one

Plain bearing 67 supported, which in turn is held stationary in a Kommutatorlagerdeckel 70. The commutator 70 is in turn secured by means of tie rods 73 which are arranged distributed over the circumference of the pole tube 28 (screws, for example, 2, 3 or 4 pieces) in the drive bearing plate 19. It supports the pole tube 28 on the drive end plate 19, and the

Commutator bearing cap 70 on the pole tube 28.

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

Rolling bearings 89 are supported on journals 92. The planet gears 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 accommodated. The planet carrier 98 is in turn in an intermediate storage 101 and a slide bearing arranged therein

104 stored. The intermediate bearing 101 is designed cup-shaped, that in this both the planet carrier 98, and the planet wheels 86th

are included. 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. The intermediate storage 101 is supported by his

Outer circumference on the inside of the pole tube 28 from. The armature 37 has on the end facing away from the commutator 52 end of the drive shaft 44 has a further shaft journal 110, which is also received in a sliding bearing 113, from. The sliding bearing 113 in turn is in a central bore of the

Planet carrier 98 recorded. The planet carrier 98 is integral with the Output shaft 116 connected. This output shaft 116 is connected to her from

Intermediate bearing 101 facing away from the end 119 in a further bearing 122 which is fixed in the drive bearing plate 19, supported. The output shaft 116 is divided into several sections: Thus, the section which is arranged in the sliding bearing 104 of the intermediate bearing 101, follows a section with a so-called

Spur gear 125 (internal toothing), which is part of a so-called shaft-hub connection. This shaft-hub connection 128 in this case allows the axially rectilinear sliding of a driver 131. This driver 131 is a sleeve-like extension which is integral with a cup-shaped outer ring 132 of the freewheel 137. This freewheel 137 (Richtgesperre) consists of

Further, from the inner ring 140, which is arranged radially within the outer ring 132. Between the inner ring 140 and the outer ring 132 clamping body 138 are arranged. These clamp body 138 prevent in

Cooperation with the inner and outer ring relative rotation between the outer ring and the inner ring in a second direction. In other words, the freewheel 137 allows a relative movement between inner ring 140 and outer ring 132 in one direction only. In this

Embodiment, the inner ring 140 is formed integrally with the starter pinion 22 and the helical teeth 143 (external helical teeth).

For the sake of completeness, here is still the Einspurmechanismus

received (Fig. 1 and Fig. 2). The switch 16 has a bolt 150 which carries an electrical contact 181 and which is connected to the positive terminal of an electric starter battery, which is not shown here. This bolt 150 and also a bolt 151 is passed through a relay cover 153.

This relay cover 153 terminates a relay housing 156, which is fastened by means of a plurality of fastening elements 159 (screws) on the drive end plate 19. In Schalterl6 a pull-in winding 162 and a so-called holding coil 165 is further arranged. The pull-in winding 162 and the holding winding 165 both cause an electromagnetic state when switched on

Field which flows through both the relay housing 156 (made of electromagnetically conductive material), a linearly movable armature 168 and an armature circuit 171. The armature 168 carries a push rod 174, which is moved in the direction of linear retraction of the armature 168 in the direction of a switching pin 177. With this movement of the push rod 174 to the shift pin 177 this is made its rest position in the direction of the contact 181 and a contact 180 moves, so that an attached to the contacts 180 and 181 end of the switching pin 177 contact bridge 184 connects both contacts 180 and 181 electrically. As a result, electric power is supplied from the bolt 150 via the contact bridge 184 and the bolt 151 to the power supply 61 and thus to the carbon brushes 58. The starter motor 13 is energized.

The Schalterl6 or the armature 168 but also has the task, with a tension member 187 to move the drive bearing plate 19 rotatably arranged lever. This lever 190, commonly called

Running fork lever, engages with two "tines" not shown here on its outer circumference two discs 193 and 194 to move a clamped between these driver ring 197 for freewheel 137 back against the resistance of the spring 200 and thereby einzura the starter pinion 22 in the ring gear 25 ,

FIG. 2 further shows a contact release spring 220, which after the

Power shutdown with respect to holding coil 165, the contact bridge 184 pushes back to its initial position. The contact release spring 220 presses against a collar 223, which sits on the shift pin 177. The contact bridge 184 has in its center a hole 226, with which the contact bridge 184 is supported on a sleeve portion 229 of an axially movable guide collar 232. This guide collar 232 has between its outer contour and the switching pin 177 a substantially cylindrical cavity 235, in which in turn a compression spring 238 is supported. This pressure spring 238 is supported on the end facing away from the contact bridge 184 of the switching pin 177 on a snap-on sleeve 241, which holds with snap elements 244 in a groove 247 stationary. Between the armature 168 and the armature return 171 acts around the snap sleeve 241 around a further compression spring 250th

FIG. 3 shows a side view of the contact bridge 184. This contact bridge 184 shows a central areal section 270 which has the hole 226 at its center (FIG. 4). From this central area section 270, which is perpendicular to the shift pin 177, radially outward from the center of the hole 226 outwards and thus from the shift pin 177 pioneering initially an outer area 273 section. Diametrically opposed to this first outer surface portion 273 is a second outer surface portion 276. Both outer planar sections 273 and 276 have an approximately circular contour. Compared with the central planar section 270, both outer planar sections 273 and 276 are deflected by the angle α. This angle α preferably has a value between 1 ° and 15 °, with 5 ° being preferred. The outer laminar portions 273 and 276 have an edge 279 at their furthest from the center of the hole 226.

As a special embodiment, it is provided for the contact bridge 184 that this consists of so-called electro-copper (E-Cu57). Furthermore, it is provided that the angle α is equal to 5 °, the hardness of the material between 100 to 130 HV 10 has (Vickers hardness measurement method). For the

Material thickness d are provided 2mm. The length L of the contact bridge 184 is selected so that the contacting of the edges 279 takes place on the contacts 180 and 181. The rigidity of the contact bridge 184 is between 150 N / mm and 250 N / mm.

FIG. 5 shows three different cross sections of the contact bridge 184. The lower part of Figure 5 shows the widest cross-section 290 at the widest point of the outer surface portion 273. The middle part of Figure 5 shows the cross section 293 at the junction between the outer surface portion 273 and the central surface portion 270. At this point is the Contact bridge 184 fitted. The uppermost region of FIG. 5 shows the cross section 296, which is divided into two partial surfaces 297. The cross section BB shows the cross section 296, which occurs at the widest point of the contact bridge 184 and is simultaneously cut centrally through the hole 226. FIGS. 2, 3, 4, 5 accordingly show that the contact bridge 184 is guided by means of a switching pin 177 in a bearing in the form of a guide collar 232, and the contact bridge 184 between the switching pin 177 and the edge 279 has a region with the largest cross section 290 and between the region with the largest cross section 290 and the switching pin 177 has a reduced cross-section area 293. With regard to the different cross sections 290, 293 and 297, it is provided that for the sum of the cross sections 297 it should be assumed that they are greater than or equal to the cross section 293. FIG. 6 shows a plan view of the contact 180 of the bolt 151. As can be seen there, the bolt 151 shown there is equipped with a contact 180 whose contact surface 300 has a corrugation which is an annular corrugation 310 (elevations). This contact surface 300 or its corrugation is such that, as shown in Figure 7, in the

Cross-sectional view results in a wavy contour. This corrugated contour may be, for example, a sinusoidal profile or a similar profile with a wave shape, i. H. The corrugation illustrated here is an annular corrugation 310, that is to say the corrugated contour 303 or its "peaks and valleys" are coaxially oriented around the center line 306 of the bolt 151 in the example.

In the context of the second exemplary embodiment, FIG. 8 and following, a contact bridge 184, as is known from FIG. 4, is paired with a contact pin 151 whose contact surface 300 does not consist of an annular corrugation 310 but of a straight corrugation 309, FIG in section 8 drawn section line IX-IX is shown in Figure 9. Accordingly, there is shown the section through the contact pin 151, the associated bolt head 152 and the contact 180. As shown there in section, it recognizes there the Geradriffelung 309, on which the edge 279 of the contact bridge 184 is arranged. With reference to Figure 8 is located there as different sections in the

Switching, d. H. Contact between contact bridge 184 and the contact 180 to be moved. Thus, the arrow at the right edge of Figure 8 with the

Designation V ₁₈₄ the speed, ie the movement of the contact bridge

184 for making contact between contact 180 and contact bridge 184. After hitting edge 279 on contact 180, the edge moves

279 by the movement of the contact bridge 184 and the inclination angle α between the outer planar portion 273 and the central surface

Section 270 in a short movement in the direction of the arrow with the

Designation V279. With reference to FIG. 9, this means a sliding of the edge 279 in the direction of the observer on the straight corrugation 209. The first embodiment and also the second embodiment show an electromagnetic switch 16 for a starting device 10, said electromagnetic switch 16 has two contacts 180 and 181, which are electrically conductively connected to each other by a movable contact bridge 184. It is thereby provided that at least one of the two contacts 180 or 181 preferably has a contact surface 300 firmly connected to a contact pin 151 or 150. In this case, the contact surface 300 has elevations, which preferably lie substantially in one plane. An electrical contact between the contact bridge 184 and the contact edge 279 of the contact bridge 184 is arranged so that these from the

Impact on the contact surface 300 essentially one

Multiple point contact between contact 180, 181 and contact bridge 184 allows. Depending on the orientation of the straight corrugation 309 or relative position of the individual elevations of the straight corrugation 309 to the edge 279, initially only a single point contact between contact 180 or 181 and

Contact bridge 184 be possible.

The straight corrugation 309 should ideally be designed as sinusoidal longitudinal corrugation. With regard to the interaction of contact 180 or 181 and the contact bridge 184, the hardness of the contact 180 or 181 should be less than or equal to the hardness of the contact bridge 184. This is to ensure that not the contact bridge 184 but the contacts 180 and 181 wear out.

Figure 10 shows a third embodiment of a contact bridge 184, as is known from Figure 4 and a contact 180, the contact surface 300 is at least substantially planar. The contact bridge 184 moves as in the embodiment of Figure 8 accordingly. Ie. the edge 279 moves transversely to the marked longitudinal axis 312 of the contact pin 151. In this case, the edge scrapes 279 along the contact surface 300. Macroscopically, the contact surface between the contact bridge 184 and the contact surface 300 results in a line shape. The embodiment of Figure 10 accordingly shows an electromagnetic switch 16 for a starting device 10 with two contacts 180, 181, which are electrically conductively connected to each other by a movable contact bridge 184, wherein at least one of the two contacts 180 or 181 preferably one with a contact pin 151 has fixed contact surface 300. It is envisaged that the

Contact surface 300 is at least substantially planar and an electrical contact between contact bridge 184 and contact 180, 181 giving edge 279 of the contact bridge 184 is arranged so that from the impact on the contact surface 300 is substantially a line contact between contact 180, 181 and contact bridge 184th allows.

A further definition of the manner in which the contact bridge 184 and the contact 180 or the contact 180 and the outer planar section 276 are oriented relative to one another may be indicated with reference to FIG. Thus, between the outer planar portion 276 and the longitudinal axis 312 of the contact pin 151, an angle β may be indicated which, for example, lies in the plane formed by the longitudinal axis 312 and the central axis of the hole 226 (FIG. 4). This central axis of the hole 226 has the

Designation 315 and coincides with the axis of movement of the shift pin 177, see also Figure 2.

According to this definition, an electromagnetic switch 16 is for a

Starting device 10 is provided with two contacts 180 and 181, which are electrically conductively connected to each other by a movable contact bridge 184, wherein at least one of the two contacts 180 or 181 preferably having a contact pin 151, 150 fixedly connected contact surface 300, wherein one for contact 180 directed surface 318 of the contact bridge 184 and a longitudinal axis 312 of a contact pin 151 between them a directed to a central axis 315 of the switch 16 angle ß include, which is greater than 90 °. This definition applies to the rest position or up to the position of the switching bridge 184, in which the contact bridge 184, the surface 300 just does not touch or powerless. With respect to the angle ß is provided that this is between 91 ° and 105 °, preferably by 95 °. FIG. 11 shows a fourth exemplary embodiment of a switch 16. Since the details of the switch of Figure 11 differ from those of the switch according to Figure 2 only in a few details, only these differences will be discussed below.

While the contact bridge 184 according to FIG. 2 has outer planar sections 276 and 273, which are inclined or bent in the direction of the contacts 180 and 181, the outer planar sections 276 and 273 of the contact bridge 184 are not connected to the contacts 180 and 180, respectively 181 inclined, but inclined away from them. Correspondingly, the angle of inclination α has a different sign compared with the exemplary embodiment according to FIG. 2 and the central areal section 270. The angle β is defined here as an angle which is arranged between the contact 180 directed surface 318 of the contact bridge 184 and a longitudinal axis 312 of a contact pin 151. The angle ß is oriented in such a way that it lies in a plane which is out of the

Longitudinal axis 312 and the central axis 315 is formed. The angle ß is directed radially outward and is greater than 90 °. With respect to the angle ß is provided that this is between 91 ° and 120 °. These too

Size indication refers to the position of the contact bridge 184 in the rest position, or before it touches the contact surface 180. In the example according to FIG. 11, for example, the contacts 180 and 181 are designed such that they have an edge 320 which, from the moment when the contact bridge 184 impinges on the contact surface 300, moves relative to the central axis 315 between the contact bridge 184 and Contact 180 or 181 causes. In this case, an edge 320 of the contact scrapes 180 and 181, respectively, at the contact bridge

184th

With respect to the angle α is provided that this has a value between -1 ° and -30 °. The choice of the angle is dependent on the coefficient of friction between the contact partners. Here, in the case where it is a high coefficient of friction, that the angle can be rather smaller, while at low coefficients of friction the angle is rather large.

The fifth embodiment according to FIG. 12 shows, in a basic representation, two contact bolts 150 and 151 which, with their contact surfaces 300, belong to the outer planar sections 273 and 276 are oriented. The length of the contact bridge 184 transverse to the central axis 315 is greater than the outermost distance of the two contact pins 151 and 150 to each other. Accordingly, the outer laminar portions 273 and 276 respectively do not scrape at one of their edges against the surfaces 300 of the contact pins 150 and 151. In this case, the contact bridge 184 switches against sharp edges 330 of the contacts 180 and 181, respectively.

In a modification of the embodiment of Figure 12 switches the

Contact bridge 184 according to Figure 13 not against extreme edges of

Contact pin 151 or 150, but against angled edges 333rd

FIG. 14 shows a seventh exemplary embodiment of a pairing of contact bridge 184 and contact pins 151 and 150, respectively. This seventh

Embodiment is a modification of the embodiment of Figure 13 and differs from this in that the contact bridge 184 no longer protrudes beyond the outermost contours of the two contact surfaces 300 and contact pins 151 and 150, respectively. Again, the contact bridge 184 switches against an angled edge 333 of the contact pins 150 and 151th

FIG. 15 shows a further, eighth exemplary embodiment of a pairing of a contact bridge 184 and two contact pins 150 and 151, respectively. Both contact pins 151 and 150 have in the region of their bolt heads 152 directed towards each other two bevels 336. Although these two bevels 336 are substantially directed to each other, but not parallel to each other. A contact bridge 184 is present whose length is shorter than the largest distance of the chamfers 336 to each other, but greater than the smallest distance between the two bevels 336 to each other. In this

Embodiment scrapes an edge 279 of the outer laminar portions 273 and 276 at the bevels 336th

FIG. 16 shows a contact bridge 184 in a further alternative

Embodiment shown. This contact bridge also has a central areal section 270 and two outer areal sections 273 and 276, respectively. The central area 270 also has a hole 226 in its center on. The edges 279 are in contrast, for example, to the embodiment of Figure 3 and Figure 4 is not round, but straight. The outer planar sections 273 and 279 are also shown at an angle α to the central planar section 270 analogous to the embodiment of Figure 3 and Figure 4.

As an alternative to the embodiment according to FIG. 16, as shown in FIG. 17, the contact bridge 184 can have two outer planar sections 273 and 276, which in contrast to the exemplary embodiment according to FIG. 16 are slotted in such a way that the respective planar sections are designed as two lugs 340 , Instead of the designation flags would be for example also the designation

Metal flaps suitable.

Figure 18 shows a contact bridge 184, which is designed substantially rectangular. In turn, it has a central planar section 270 and two outer planar sections 276 and 273. Central in the planar section 270, in turn, a hole 226 is arranged. While a top view can be seen in FIG. 18a, a sectional view of the contact bridge 184 is shown in FIG. 18b. This sectional view shows the bending of the outer flat sections 273 and 276 by the angle a. To influence or increase the flexibility of the outer planar sections 273 and 276, these are connected via notches 350 with the central planar section 270. The notches may, as here in the example, be arranged on both sides of the surface of the contact bridge 184, but also, if appropriate, alternatively on one side. These notches 350 are here designed as semicircular corrugations to reduce the cross section and reduce the flexural rigidity of the contact bridge 184.

As shown in FIGS. 19a and 19b, a further contact bridge 184 is shown in a plan view and a sectional view. The constrictions to reduce the cross section or reduce the flexural rigidity of

Contact bridge 184 need not, as shown in Figure 18, are introduced to the outer contour. It can also recesses in the preferably rectangular shaped contact bridge 184 are introduced. In Figure 19, two circular recesses 353 are exemplified, the reduce the cross section. The recesses may have any shape, for. B. be executed rectangular or rounded.

FIG. 20 shows a contact bridge 184 in longitudinal section. This contact plate in turn has a central areal section 270 and two outer areal sections 273 and 276. The central planar section 270 in turn has a hole 226, as have the previous embodiments for contact bridges 184 also. This contact bridge 184 consists of several layers. A first layer is a carrier layer 400 and a second layer attached to this carrier layer 400 is a contact layer 403. In the case of the contact bridge 184 embodied here, the properties are optimized by forming the contact bridge 184 of a plurality of layers. Thus, the first layer, namely the backing layer 400, has favorable properties as a retaining, stability and elasticity-imparting element. By contrast, the contact layer 403 has optimized properties with regard to the contact between contact bridge 184 and contact 180 or 181. It is envisaged that the carrier layer 400 consists of a copper or a silver alloy or steel or bronze or brass. For the contact layer 403, it is provided that it consists of a copper, tin, gold or silver alloy or a metal-metal oxide composite material.

For the contacts 180 and 183 of the contact pins 151 and 150 is intended in

In general, these are also made of electro-copper and have a hardness between 100 and 130 HV10.

Due to the shape of the contact bridge 184, for example, according to FIG. 4

CEinschnürung "), Figure 16, Figure 17, Figure 18 and Figure 19 is the

Reduced spring stiffness compared to previously known contact bridges. This leads to a greater elastic deformation when connecting the contacts 180 or 181 with the already described advantages of increased damping and the destruction of a resulting oxide layer.

With respect to the edges 279 and 320, it is provided that this has a radius of <0.3 mm. This leads to a "chisel effect", so that the edges 279 and 320 at the opposite contact interfering layers remove. Contacting properties are thereby significantly improved. In the region of the edges 279 and 320, it is preferable here for an area-wise or linearly very cohesive connection due to switch-on arcs. By tearing these cohesive connections undergoes the respective edge 279 and 320 a constantly new sharpening, which remains even after repeated switching characteristics or point contact between edge and mating contact. The edges 279 and 320 moreover have the advantage that ice layers formed by possible atmospheric moisture in the switch are broken on the contacts 180 and 181, respectively.

With regard to the material thickness of the contact bridge 184, it is generally provided that the corresponding metal sheet preferably has a thickness of between 1 and 4 mm.

Furthermore, a method for switching the electromagnetic switch 16 is provided, wherein it has two contacts 180 and 181, which are connected by a movable contact bridge 184. When contacting the contact bridge 184 with at least one of the two contacts 180 and 181 acts a scrape movement between the contact bridge 184 and the

Contact surface 300 of contact 181 and 180, respectively

Contact bridge with its surface in the form of an edge 279 over the

Contact surface 300 of the contact 180 or 181, or the contact surface 300 of the contact 180 or 181 with its surface shape of an edge 320 slides over the contact bridge 184. A possible cohesive connection between the contact bridge 184 and the contacts 180 and 181 should in the case of release a thrust load in the cohesive connection (welding) can be solved. The thrust load acts in the

Power transition area 500.

The edge 279 serves to scrape on the surface of the contacts 180 and 181, thereby creating friction and ultimately converting energy. The energy to be converted is the kinetic energy of the contact bridge 184 and the moving during the switching operation parts, such as the switching pin 177, the snap sleeve 241, compression spring 238, Guide collar 232, collar 223. This kinetic energy is generated by the

Friction of the contact bridge 184 on the contacts 180 and 181 the

Reduce kinetic energy so far that a rebound of the contact bridge 184 substantially no longer occurs and thereby the tendency to form arcing between the contacts 180 and 181 and the contact bridge 184 is at least greatly reduced.

Figure 21 A shows a side or sectional view of the contact bridge 184, which makes an electrical connection with the contact 180 of the bolt 151. As can be seen there, the contact 180 or its contact surface 300 has a corrugation (elevations), which is an annular corrugation 310. This contact surface 300 or its corrugation is such that, in the cross-sectional view results in a wavy contour. This corrugated contour may be, for example, a sinusoidal profile or a similar profile with a wave shape, i. H. The corrugation shown here is an annular corrugation 310, that is to say the corrugated contour 303 or its "peaks and valleys" are in the example preferably oriented coaxially around the center line 306 of the pin 151. It is envisaged that the contact bridge 184 slides or rubs along an edge 420 of the wave-shaped contour 303 when switching or contacting with its outer areal section 276. Flank here means that it is a flat section of the

undulating contour 303 which faces away from the central axis 315 of the switch 16. The planar section of the wave-shaped contour 303 is preferably arranged in three spatial dimensions. A contact surface between the surface 318 and the contact surface 300 resulting from the contact between the contact bridge 184 and the contact 180 is crescent-shaped, so that a width of the contact surface at its ends (crescent ends) is narrower than between the two ends. This leads to an easier release of the surface 318 and the surface of the contacts 180, 181 and thus to a slight release of possibly cohesive connection. The sickle shape adjusts itself during the switching and normally becomes larger when the surface 318 slides over the contact surface 300. This is due to the self-adjusting rolling motion. The surface 318 is always flatter in the course of the contacts 180, 181, so that the sickle shape is larger in the switching process. The contact bridge 184, with its contact surface 180, 181 directed surface 318 on the wavy contour 303 perform a combined movement, which is both sliding and rolling. As a result, upon release of the surface 318 from the surface of the contact 180, 181 - especially when possibly welding the

Contact partner - not just a thrust load but also a

Zugkraftbelastung act, the z. B. acts on the side of the current transfer surface 500, which is directed to a longitudinal axis 312 of the contact pin 150, 151. The

Location "longitudinal axis 312 of the contact pin 150, 151" would be synonymous with other contacts made synonymous with the center.

FIG. 21B shows which general shape and position forms a common current transfer surface 500 (contact surface) between contact bridge 184 and contact 180. The current transfer surface 500 (contact surface) has a sickle shape. Between the current transition surface 500 and the longitudinal axis 312, which is arranged in the drawn center, is at least one arcuate maximum line 503, which forms a dividing line between an inner edge 506 and a flank 420 (outer edge) in the example. At a low point 509, a minimum line 512 separates an inner edge 506 from an edge 420 (outer edge).

Alternatively, the current transition surface 500 may also intersect the arcuate maximum line 503, or be at its original position (eg, through wear). However, the largest part of the current transition surface 500 is still - viewed from the longitudinal axis 312 - beyond the maximum line 503 or beyond their original position.

According to FIG. 21C, the contact bridge 184 makes contact with the contact 180. The contact 180 does not have an annular corrugation 310 with a plurality of corrugated contours 303, as in FIG. 21B, but also a contact 180, which is at least partially round, with a circular plateau 515 which extends radially outwards an at least partially round edge 420 (outer edge) drops. Also in this case, as shown in Fig. 21B, a current transfer surface 500 (contact surface) having sickle shape is formed. As shown in FIG. 21C by means of a dot-dash line, the contact 180 may also be provided with only one shaft in the outer region of the contact 180. Also in this case, as shown in Fig. 21B, a current transfer surface 500 (contact surface) having sickle shape is formed.

The smaller the angle α, the larger the arc angle of the

Current transfer area 500 (contact area). At a rather large angle (Figure 21A), the arc angle is small, for example 30 °, at a rather small angle the arc angle is large, for example 140 °.

FIG. 22A shows a diagram in which, depending on a

Constriction ratio and a lever arm ratio, the bending stress is shown in the constriction area. The constriction area is the area of the contact bridge 184, which is the waisted shown in Figure 5

Section 293 corresponds. In principle, this applies to all in cross section

reduced contact bridges 184, as shown for example in Figures 16 to 19. The three curves K25, K50 and K75 shown there represent different parameters. A lever arm ratio of 25% is shown in the curve K25, a lever arm ratio of 50% is shown in K50, and a lever arm ratio of 75% is shown in K 75. "lever arm ratio" means that with reference to Figure 22B a ratio of LH / L = Vi = 25% The greater the lever arm ratio is, the greater is the stress S in the cross section 293 under the same loading with a force

Constriction ratio V considered. V is the quotient of the width BE to the width B184. To avoid bouncing or to prevent and in friction,

To convert sliding movement is provided that the bending stress S in

Cross section 293 is greater than 20 N / mm2. Furthermore, the bending stress S should be less than 100N / mm 2. It is desirable for the necking ratio V to be less than or equal to 75%, preferably greater than 25%. A ratio between 70% and 35% has proven particularly favorable.

It is further provided a method for switching a

electromagnetic switch of a starting device 10, with two contacts 180, 181, which are electrically conductively connected to each other by a movable contact bridge 184, wherein when contacting the contact bridge 184 with at least one of the two contacts 180, 181 acts a scraping movement between the contact bridge 184 and a contact surface 300 of the at least one contact 180, 181, wherein the contact surface 300 has elevations lying substantially in one plane and the contact bridge 184 an outer planar portion 276th has, wherein the contact bridge 184 in a switching position with its outer flat portion 276 at a portion of the wavy contour 303 slides or rubs, which faces away from a central axis 315 of the switch 16.

The method is configured in such a way that the contact bridge 180 slides or rubs against an edge 420 of a wave-shaped contour 303, preferably an annular corrugation 310, when it makes contact with its outer planar section 276.

It is envisaged that a cohesive connection between the contact bridge 184 and a contact 180, 181 by a thrust load in the

cohesive connection is released. Preferably acts in addition to the

Thrust load also a tensile load. Preferably, the

Thrust load and the tensile load of a rolling movement of the outer portion 276 of the contact bridge 184 on the contact surface 300 superimposed.

Claims

claims

1. Starting device with an electromagnetic switch (16), with two contacts (180, 181), which are electrically conductively connected to each other by a movable contact bridge (184), wherein at least one of the two contacts (180, 181) one with a contact pin ( 150, 151), wherein the contact surface (300) has at least one elevation with a wavy contour (303), characterized in that the in

is substantially in a plane and the contact bridge (184) an outer planar

Section (276), wherein the contact bridge (184) slides in a switching position with its outer planar portion (276) at a portion of the undulating contour (303) having its surface from a central axis (315) of the switch (16) is remote and a current transfer surface (500) between the surface (318) and the contact surface (300) is sickle-shaped.

2. Starting device according to claim 1, characterized in that between the current transition surface (500) and a longitudinal axis (312) of the contact pin (150, 151) an arcuate maximum line (503) or the current transition surface (500), the arcuate maximum line (503) intersects , where the maximum line (503) is a

Dividing line between an inner edge (506) and a flank (420, outer edge) of a wavy contour (303) of the contact (180, 181) or the highest line of a wavy contour.

3. Starting device according to one of the preceding claims, characterized

characterized in that a contact (180, 181) facing surface (318) of the contact bridge (184) and a longitudinal axis (312) of a contact pin (150, 151) between them one to a central axis (315) of the switch (16) directed Include angle greater than 90 °, wherein the angle is between 91 ° and 105 °, preferably by 95 °.

4. Starting device according to one of the preceding claims, characterized

characterized in that the contact bridge (184) is guided in a bearing by means of a switching pin (177) and the contact bridge (184) between the switching pin (177) and an edge (279) has a region with the largest cross section (290) and between the region having the largest cross section (290) and the switching pin (177) has a reduced cross section area (293).

5. Starting device according to one of the preceding claims, characterized

characterized in that the contact bridge (184) consists of a perpendicular to the switching pin (177) oriented central flat portion (270) to which from

Switching bolt (177) pioneering at least one outer planar portion (273; 276) connects, wherein between the central and the outer flat portion (273; 276) an angle (a) is present, which is not equal to 180 °.

6. Starting device according to one of the preceding claims, characterized

characterized in that at least one of the two contacts (180, 181) has a hardness which is less than or equal to a hardness of the contact bridge (184).

7. Starting device according to one of the preceding claims, characterized

in that a coefficient of friction between the contact bridge (184) and the at least one contact (180, 181) has a value between 0.1 and 2, preferably between 0.6 and 1.

8. Starting device according to one of the preceding claims, characterized

characterized in that the edge (279) has a radius of less than 0.3 mm.

9. Starting device according to one of the preceding claims, characterized

characterized in that the contact bridge (184) is a sheet, which preferably has a plate thickness (d) between 1 and 4 mm.

10. A method for switching an electromagnetic switch a

Starting device (10), with two contacts (180, 181), which are connected by a movable contact bridge (184) electrically conductive, wherein the Contacting the contact bridge (184) with at least one of the two contacts (180, 181) a frictional movement between the contact bridge (184) and a

Contact surface (300) of the at least one contact (180, 181) acts, wherein the contact surface (300) has at least one elevation lying substantially in a plane and the contact bridge (184) has an outer flat portion (276), wherein the Contact bridge (184) in a switching position with its outer surface portion (276) on a portion of the wavy contour (303) slides or rubs, which faces away from a central axis (315) of the switch (16), wherein when sliding over the contact surface (300) a

Current transition area (500) sets which is sickle-shaped.

11. The method according to claim 10, characterized in that the contact bridge (180) when contacting with its outer flat portion (276) on an edge (420) of a wavy contour (303) of a ring corrugation (310) slides along or rubs.

12. The method according to any one of claims 10, characterized in that a current transfer surface (500) has a sickle shape, wherein between the

Stromübergangsfläche (500) and a longitudinal axis (312) an arcuate

Maximum line (503) or the current transition surface (500) intersects the arcuate maximum line (503).

13. The method according to any one of claims 10 to 12, characterized in that a cohesive connection between the contact bridge (184) and a contact (180, 181) is released by a thrust load in the cohesive connection.

14. The method according to any one of claims 10 to 13, characterized in that the contact bridge (184) with its contact (180, 181) directed surface (318) on the wavy contour (303) performs a combined movement, both sliding than also rolling is.