DE102009027856A1 - Starter gearbox with dry lubrication - Google Patents

Abstract

The subject matter of the present invention relates to a system comprising an internal combustion engine and a starter (10) for cranking an internal combustion engine, the starter (10) for cranking the internal combustion engine comprising at least one device for coupling tribologically interacting parts in the starter (10), wherein the device comprises a mechanism for coupling the tribologically interacting parts, with at least one drive part and at least one output part in tribological operative connection with the drive part, friction-reducing means being provided between the drive part and output part for operation, the friction-reducing means being used as dry lubricants (300) are trained.

Description

The The invention relates to a mechanism for coupling tribologically cooperating Parts in a starter motor for internal combustion engines according to the Preamble of claim 1.

Further The invention relates to a starter motor for starting an internal combustion engine according to the preamble of claim 9.

moreover The invention relates to a system comprising an internal combustion engine and a starter motor for cranking an internal combustion engine after The preamble of claim 10.

State of the art

The Invention is based on a system with a starter or starter motor and a starter with internal reduction gear and a transmission to reduce the speed while increasing the torque according to the class of the independent claims.

object The present invention is starters for vehicles with internal combustion engines.

Out The prior art are starters for vehicles with internal combustion engines known, which is usually a DC electric motor for driving of the internal combustion engine. In such starters or starter motors is for a meshing or a hub in the sprocket Relay fork lever system and a coarse thread responsible. Of the Hub, also referred to as distance, or more precisely a meshing movement is composed as follows: A magnetic relay pulls a fork lever to the rear. At the same time is about a translation a freewheel gear pushed forward. When the relay is switched an electric motor starts to turn. It will that on a drive shaft, which also depending on the convention as output shaft can be designated, seated coarse thread turned and a driver over Flanks of the steep thread pushed forward. These axial and radial movement in conjunction with a Einspurfeder serves for Easier finding of tooth gaps in the sprocket. simultaneously is the coarse thread for force or torque transmission used. This coarse thread is in known embodiments lubricated with a steep thread grease.

By a large temperature difference in the field of application of Starters of -40 ° C and + 150 ° C, comes it causes hardening or leakage of the lubricant. Due to this phenomenon, higher frictional forces arise in the coarse thread, resulting in the switching times when loading and unloading from the sprocket increase. From a certain number of times, is about two-thirds of the duration of a start-stop starter no more lubricant and the coarse thread and the driving teeth begin to corrode, which, for example, to so-called grating rust leads.

For starters, for example, are out GB 151454 . US 1,594,825 . JP 2002-257016 . JP 2002-130097 and DE 102 90 004 T5 known.

Disclosure of the invention

Of the mechanism according to the invention, the inventive Starter motor and the inventive system with the features of the corresponding main claim or independent claim have the advantage over that as friction-reducing Medium dry lubricants are used. The in the state the technique used volatile friction reducing Agents such as fats or oils have the disadvantage that these be consumed in the operation or by the entry of dust or Can gassify dirt. This can cause it to be annoying Noise, increased wear or Failure of the starter motor also called starter come. The use of dry lubricants is eliminated this risk of failure or is at least significantly reduced. Especially by a dry lubrication in the form of a hard coating with integrated solid lubricant or with an equivalent Coating with corresponding properties on the coarse thread and / or the driver teeth, in particular their running surfaces, is a friction-minimized input and output and simultaneously achieved a corrosion protection.

By those listed in the dependent claims Measures are advantageous developments and improvements in the independent and sibling claims predetermined devices possible.

In An advantageous embodiment provides that the friction-reducing Means designed as non-volatile friction-reducing means are. These can be in the form of a solid, for example Be formed coating or the like. Through the training as a non-volatile friction-reducing agent is a Maintenance effort or a Nachfüllaufwand reduced.

In addition, it is advantageous if the non-volatile friction-reducing means comprise at least one friction-minimizing coating on the drive part and / or the driven part. As a result, the funds can be permanently applied by means of coating methods. In addition, the coating can be carried out to save space, so a size is not or only insignificantly influenced.

In an advantageous embodiment, it is provided that the coating is formed as a hard coating, in particular as a galvanic hard coating, for example by chrome plating, hard chrome plating or by electroplating with other materials such as with mixtures of chrome Teflon or the like. The hard coating in one embodiment comprises solid lubricants such as Teflon, MoS ₂ , optionally WS ₂ or graphite, which are still present in solid form even at high temperatures, as they occur in operation, and a corresponding galvanic layer as a binding and carrier phase. In particular, the hard coating has no pasty components, so that dust is not bound, whereby a failure of the transmission is avoided by a possible blocking. Due to a high resistance to aging, failure can usually be ruled out. With suitable hard coatings, a toe-in path at low temperatures can be used without restrictions.

The hard coatings of the invention are characterized in a preferred embodiment by a wide thermal range of use of about -50 ° C to greater about 400 ° C. Due to the almost constant viscosity even at temperatures below 0 ° C, the friction properties can be optimally utilized and in particular reduce the generation of noise. In order to reduce the CO ₂ emissions of motor vehicles, systems are increasingly being used in which the internal combustion engine is automatically switched off when the vehicle is at a standstill (eg at a red traffic light) (so-called start-stop systems). Especially with regard to start-stop systems, in which the vehicle for the driver to start almost unnoticed again, a low noise is of great importance. Even at high temperatures, there is an advantage of dry lubrication, for example compared with greases. The viscosity of a dry lubrication hardly decreases with increasing temperatures. In start-stop vehicles, a very large proportion of starts occur when the engine is hot. The dry lubricant remains at such temperatures at the applied location, so there is no lack of lubrication. In addition, dry lubrication can cope with the increasing power requirements of starters by aging less with correspondingly higher outputs. The fact that in a dry lubrication no paste occurs, such as greases, no dirt particles are bound, so a longer life is ensured even with starters with less space and increasing the number of carbon brushes and related increases in coal dust.]

In An advantageous embodiment provides that the hard coating designed as a hard coating with integrated solid lubricant is. Due to the solid lubricants integrated in the hard coating is an advantageous lubrication feasible. This is a lubricant due to solid lubricant in the coating surface integrated are realized. By an appropriate hard coating can be an additional, elaborate curing process save or at least reduce a hardening effort.

Preferably is provided that at least one of the interacting parts is formed as a coarse thread or includes a coarse thread. The coarse thread preferably has a dry lubricant. At least one of the interacting parts preferably has one Dry lubricant on. Preferably, both have cooperating Dispense a dry lubricant. By means of suitable dry lubrication leaves increase the performance of starter motors. Especially The load on the individual parts is reduced, resulting in longer Runs leads.

In a further advantageous embodiment of the invention is provided that the other part of the cooperating parts, which with the coarse thread cooperates, as a driver toothing, in particular a Sprocket, is formed. The dry lubrication leaves to use so effectively in existing starter motors.

Not last is provided in a further advantageous embodiment, that the friction-reducing agent of one of the parts at least partly different from the friction reducing means of other part are formed. In this way, tribological can be realize optimized, co-operating friction pairings. For example The coarse thread can be hard chromed with a solid lubricant be educated. The driver teeth can then be coated with a material such as hard chrome, bronze, silver or iron.

The starter motor according to the invention for starting an internal combustion engine, comprising at least one device for coupling tribologically cooperating parts in a starter motor for internal combustion engines, wherein the device comprises a mechanism for coupling the tribologically interacting parts, with at least one drive part and at least one with the drive part in tribologically operative connection Stripping section, with friction reducing means between An Drive part and driven part are provided for operation and the friction reducing means are formed as dry lubricant, has the advantage over the prior art that due to the dry lubrication life is increased and the starter for smaller spaces and larger loads can be interpreted. The internal combustion engine is preferably an internal combustion engine. The starter motor can be configured as a star-excited or permanent-magnet starter motor.

The inventive system comprising an internal combustion engine, with at least one device for coupling tribologically cooperating Parts in a starter motor for internal combustion engines, wherein the starter motor for cranking the engine at least a device for coupling tribologically interacting parts in the starter motor, the device having a mechanism for coupling the tribologically cooperating parts, with at least one drive part and at least one with the drive part tribologically operatively connected output part, wherein friction reducing Middle between drive part and output part for a Operation are provided, wherein the friction reducing means are designed as dry lubricants, also has the Advantages that due to the dry lubrication, the maintenance intervals and the lifespan are increased and the starter for smaller spaces and larger ones Loads is interpretable.

Brief description of the drawings

embodiments The invention is illustrated in the drawings and in the following Description explained in more detail. Show it:

1 a starting device in longitudinal section and

2 an enlarged section of a starter in a side view.

Description of the embodiment

1 shows a starting device in a longitudinal section. In the 1 is a starting device - or just a starter - 10 shown. This starting device 10 has, for example, a drive or starter motor 13 and an engagement relay 16 on. The starter motor 13 and the engagement relay 16 are on a common drive end shield 19 attached. The starter motor 13 Functionally, it serves a pinion - more precisely the starter pinion - 22 drive it when in the sprocket 25 the internal combustion engine, not shown here is eingespurt.

The starter motor 13 has a pole tube as a housing 28 on, the pole pieces on its inner circumference 31 carries, each from a field winding 34 are wrapped. The pole shoes 31 in turn surround an anchor 37 that made a slats 40 built anchor package 43 and one in grooves 46 arranged armature winding 49 having. The anchor package 43 is on a drive shaft 44 pressed. At the starter pin 22 opposite end of the drive shaft 44 is furthermore a commutator 52 attached, among other things from individual Kommutatorlamellen 55 is constructed. The commutator bars 55 are in known manner with the armature winding 49 electrically connected in such a way that when the commutator bars are energized 55 through carbon brushes 58 a rotary motion of the anchor 37 in the pole tube 28 results. One between the Einspurrelais 16 and the starter motor 13 arranged power supply 61 supplies both the carbon brushes when switched on 58 as well as the excitation winding 34 with electricity. The drive shaft 44 is commutator side with a shaft journal 64 in a plain bearing 67 supported, which in turn in a Kommutatorlagerdeckel 70 is held stationary. The commutator cover 70 turn is by means of tie rods 73 that go beyond the circumference of the pole tube 28 are arranged distributed (screws, for example, two, three or four pieces) in the drive end shield 19 attached. It supports the pole tube 28 at the drive end plate 19 off, and the commutator bearing cap 70 at the pole tube 28 ,

In drive direction closes to the anchor 37 a so-called sun wheel 80 on, the part of a planetary gearbox 83 is. The sun wheel 80 is from several planet wheels 86 surrounded, usually three planet wheels 86 by means of roller bearings 89 on axle journal 92 are supported. The planet wheels 86 roll in a ring gear 95 off, in the pole tube 28 is stored outside. Towards the output side closes to the planetary gears 86 a planet carrier 98 in which the axle journals 92 are included. The planet carrier 98 will turn into an interim storage 101 which consists of planetary gear 83 may be formed, and a sliding bearing arranged therein 104 stored. The interim storage 101 is designed pot-shaped, that in this both the planet carrier 98 , as well as the planet wheels 86 are included. Furthermore, in the cup-shaped intermediate storage 101 the ring gear 95 arranged, which ultimately by a cover 107 opposite the anchor 37 closed is. Also the interim storage 101 supports with its outer circumference on the inside of the pole tube 28 from. The anchor 37 indicates that of the commutator 52 opposite end of the drive shaft 44 another shaft journal 110 on, who also in a plain bearing 113 is absorbed, from. The plain bearing 113 in turn is in a central hole of the planet carrier 98 added. The planet carrier 98 is integral with the output shaft 116 connected. This downforce wave 116 is with her from the interim storage 101 opposite end 119 in another camp 122 , which in the drive end shield 19 is fixed, supported. The output shaft 116 is divided into different sections: So follows the section that is in the plain bearing 104 of the interim storage 101 is arranged, a section with a so-called spur toothing 125 (Internal toothing), which may be embodied in other embodiments as helical teeth, which is part of a so-called shaft-hub connection. This shaft-hub connection 128 allows in this case 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 is. This freewheel 137 (Richtgesperre) consists further of the inner ring 140 that is radially inward of the outer ring 132 is arranged. Between the inner ring 140 and the outer ring 132 are clamp bodies 138 arranged. These clamp bodies 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 the inner ring 140 and outer ring 132 only in one direction. In this embodiment, the inner ring 140 integral with the starter pinion 22 and its helical toothing 143 (External helical teeth) executed.

For the sake of completeness, the single-track mechanism should be considered here. The push-in relay 16 has a bolt 150 on, which is an electrical contact and which is connected to the positive terminal of an electric starter battery, which is not shown here. This bolt 150 is through a relay cover 153 passed. This relay cover 153 closes a relay housing 156 from, by means of several fasteners 159 (Screws) on the drive end plate 19 is attached. In the engagement relay 16 continue to be a pull-in winding 162 and a so-called holding winding 165 arranged. The intake winding 162 and the holding winding 165 both cause each in the on state an electromagnetic field, which both the relay housing 156 (made of electromagnetically conductive material), a linearly movable armature 168 and an armature conclusion 171 flows through. The anchor 168 carries a push rod 174 , when linear insertion of the anchor 168 towards a shift pin 177 is moved. With this movement of the push rod 174 to the shift pin 177 This is from its rest position towards two contacts 180 and 181 moved, so one on to the contacts 180 and 181 located end of the shift bolt 177 attached contact bridge 184 both contacts 180 and 181 connects electrically with each other. This is done by the bolt 150 electrical power via the contact bridge 184 away to the power supply 61 and thus to the carbon brushes 58 guided. The drive motor 13 is energized.

The engagement relay 16 or the anchor 168 but also has the task, with a tension element 187 one the drive end shield 19 to move rotatably arranged lever. This lever 190 , usually designed as a fork lever, engages with two "tines" not shown here on its outer circumference two discs 193 and 194 to a between this clamped driving ring 197 to the freewheel 137 towards the resistance of the spring 200 to move and thereby the starter pinion 22 in the sprocket 25 einzuspuren.

2 shows an enlarged section of a starter 10 in a side view. The starter 10 essentially corresponds to the starter 10 according to 1 and for like or similar components, like reference numerals are used. A thread formed on the drive shaft or, depending on the designation of the output shaft, is formed as a coarse thread SG. The coarse thread SG is meshing with a driving teeth MV on a driver 131 engaged. In this case, at least running surfaces of the driving teeth MV formed as a hard coating dry lubricant 300 on. By a rotational movement of the output shaft 116 and a Oszillationshub, represented by the arrows R and H, there is a meshing of the Andrehritzels 22 in the sprocket 25 , For this purpose, a magnetic relay (not shown here) pulls a fork lever, also not shown here to the rear. At the same time, the on-and-off gear is being translated 22 pushed forward. When the relay is switched, the starter motor starts 13 to turn. It will do this on the output shaft 116 seated coarse thread SG turned and the driver 131 pushed forward over flanks. This axial and rotational movement (arrows R, H) in conjunction with a Einspurfeder serve to facilitate finding tooth gaps in a ring gear. At the same time the coarse thread SG is used for power or torque transmission.

By The use of dry lubricants is a Einspurvorgang improved, as by a dry lubrication in the form of a hard coating with integrated solid lubricant or with an equivalent Coating with corresponding properties on the coarse thread and / or the driver teeth, in particular their running surfaces, a friction-minimized entry and exit and at the same time Corrosion protection achieved.

QUOTES INCLUDE IN THE DESCRIPTION

This list The documents listed by the applicant have been automated generated and is solely for better information recorded by the reader. The list is not part of the German Patent or utility model application. The DPMA takes over no liability for any errors or omissions.

Cited patent literature

• - GB 151454 [0008]
• US 1594825 [0008]
• - JP 2002-257016 [0008]
• - JP 2002-130097 [0008]
• - DE 10290004 T5 [0008]

Claims (10)

Mechanism for coupling tribologically co-operating parts in a starter ( 10 ) for internal combustion engines, comprising at least one drive part and at least one with the drive part in tribologically operative connection driven part, wherein friction reducing means between the drive part and driven part are provided for operation, characterized in that the friction-reducing agent as a dry lubricant ( 300 ) are formed. Mechanism according to claim 1, characterized in that that the friction-reducing means non-volatile friction-reducing Means include. Mechanism according to claim 1 or 2, characterized that the non-volatile friction-reducing agents at least a friction-minimizing coating on the drive part and / or Stripping part include. Mechanism according to one of claims 1 to 3, characterized in that the coating as a hard coating is trained. Mechanism according to one of claims 1 to 4, characterized in that the hard coating as a hard coating is formed with integrated solid lubricant. Mechanism according to one of claims 1 to 5, characterized in that at least one of the cooperating Parts is designed as a coarse thread (SG). Mechanism according to one of claims 1 to 6, characterized in that the other of the parts, which with the Steep thread (SG) cooperates as a driver toothing (MV), in particular a sprocket is formed. Mechanism according to one of claims 1 to 7, characterized in that the friction reducing means of the parts at least partially different from the friction-reducing Means of the other part are formed. Starter ( 10 ) for starting an internal combustion engine, with at least one device for coupling tribologically interacting parts in a starter ( 10 ) for internal combustion engines, characterized in that the device comprises a mechanism for coupling the tribologically cooperating parts, with at least one drive part and at least one with the drive part in tribologically operative connection driven part, wherein friction reducing means between the drive part and driven part are provided for operation, said the friction-reducing agents as dry lubricants ( 300 ) are formed. the friction reducing means are designed as non-volatile friction reducing means. System comprising an internal combustion engine and a starter ( 10 ) for starting an internal combustion engine, characterized in that the starter ( 10 ) for starting the internal combustion engine at least one device for coupling tribologically cooperating parts in the starter ( 10 ), wherein the device comprises a mechanism for coupling the tribologically co-operating parts, with at least one drive part and at least one driven part in tribological operative connection with the drive part, wherein friction reducing means between drive part and driven part are provided for operation, said friction reducing means as Dry lubricants ( 300 ) are formed.

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