EP2425116B1 - Starter having a switchable number of pole pairs - Google Patents

Description

State of the art

The invention relates to a starter for an internal combustion engine according to the preamble of the independent claim. Such a starter is described for example in the Automotive Handbook of Bosch, 25.Auflage, S.986 in the embodiment as a thrust screwdriver starter, which is controlled by a so-called engagement relay. This relay takes over the functions indenting, ie meshing of the pinion of the starter motor in the ring gear of an internal combustion engine, and switching the main current of the starter motor. When meshing the pinion in the ring gear while a tooth of the pinion can hit a tooth of the ring gear, which is why the meshing is supported by a Einspurfeder. Although this known starter design requires only a single relay and can therefore be produced relatively inexpensively, on the other hand arise for the Einspurvorgang and for the switching operation of the high motor current difficult working conditions. In particular, in this embodiment of the switching device for the main current of the starter whose maximum possible torque is already generated when cranking out of a standstill out. If in this case the pinion of the starter motor is not fully into the ring gear of the Internal combustion engine is eingespurt, it can at least over the life of the starter away to unduly large loads of the teeth come with the risk of breaking out of one or more teeth.

To improve the Einsspurvorganges, especially in high-performance starters, it is known from the aforementioned reference to turn the motor current in two stages in so-called push-drive starters, in a first stage, the pinion of the starter is moved against the ring gear of the engine and at the same time Anchor of the starter motor is fed with a reduced current, so that the armature and with it the pinion rotate when meshing, thus facilitating the Einspurvorgang. The meshing mechanism is in this case provided with a pawl, which closes only at the end of the Einspurvorgangs the pinion another switching contact of the relay and via this the main circuit of the motor. As a result, the Einspurvorgang and the switching of the main current of the motor can be done in two separate operations, but the structure of the contact relay is more complex and prone to failure. However, the main current of the starter motor is also switched in a single switching operation, so that the maximum torque of the starter is already applied to the pinion-ring gear connection, while the internal combustion engine still stands still with its large mass.

Disclosure of the invention

The starter according to the invention with the features of the independent claim has the advantage that by the meshing of the pinion with a delayed connection of Partial windings of the field winding the characteristics of the starter motor are influenced so that the teeth between the starter motor and engine during Einspurvorgang is significantly less burdened. Furthermore, the speed behavior during startup of the starter, in particular by the shift of the idle speed, positively influenced. By adding additional pole pairs with the associated part windings of the field winding the maximum available torque of the starter is reached only at a time when the starter pinion fully meshed in the ring gear of the engine and the engine is already broke loose. As a result, excessive loads on the teeth are avoided and their life is significantly increased.

For an advantageous change in the engine characteristics, it is particularly useful if the partial windings of the field winding can be operated either in series and / or in shunt to the armature of the motor. While the torque of the motor when starting the motor is reduced in particular by the reduction of the partial windings operated in series, it is possible by the connection of individual part windings in shunt to armature to straighten the speed characteristic and make the speed behavior of the starter less dependent on the load current, in particular for reducing the idle speed.

A particularly advantageous design of the starter according to the invention is obtained when the partial windings of the field winding are arranged on separate poles of the stator, in particular, when the stator is formed six poles with six partial windings on three pole pairs, wherein the partial windings in pairs on opposite poles are applied to the stator circumference. This results in their switching and delayed connection a symmetrical arrangement of the exciter part windings, whereby the startup of the engine is improved.

An expedient embodiment of the switching device of the starter is obtained when individual or all switching elements of the switching device are designed as relays. Instead, suitable semiconductor components can be used for all or individual switching elements but also for switching larger currents, preferably transistors or GTO (Gate Turn-Off) thyristors.

A particularly simple and inexpensive starter design is obtained in a single-stage energization of the starter motor, a pull-in winding switches together with a holding winding of the Einspurrelais a normally open, energized on the first one or more exciter part windings of the starter motor and the starter motor until the end of Einspurbewegung the Einspurrelais on the entire excitation winding is energized. Such an arrangement requires in a known manner a Einspurfeder, which supports in conjunction with a coarse thread, especially in a so-called tooth on tooth position of the pinion and the ring gear, the Einspurvorgang.

The holding winding and the pull-in winding of the Einspurrelais preferably sit on the same relay core. In the case of a single-stage energization they are switched in the same direction, whereby the necessary total flux is achieved with a smaller number of turns and / or lower excitation current. In opposite flooding of the common relay core, as used in two-stage energization of the motor, the winding with the smaller flooding are used to dampen the switching process. The number of turns and the excitation currents of the holding winding and the pull-in winding are expediently chosen so that the holding winding with a high number of turns and a sufficient excitation current causes the switching operation of the Einspurrelais, while the pull-in winding is equipped with a significantly lower number of turns, but a much higher excitation current leads , which is sufficient to easily twist the anchor when meshing.

Further details and advantageous embodiments of the invention will become apparent from the dependent claims and the description of the embodiments, which are illustrated in the drawings and explained in more detail in the following description.

Figur 1

eine Prinzipdarstellung eines Schub-Schraubtrieb-Starters mit einer Reihenschlusswicklung und einer Nebenschlusswicklung im Stator,

Figur 2

ein Schaltschema eines einstufig bestromten Starters in herkömmlicher Ausführung mit einer Reihenschlusswicklung und gegebenenfalls einer zusätzlichen Nebenschlusswicklung,

Figur 3

ein Schaltschema eines einstufig bestromten Starters mit einer Reihenschluss-Erregerwicklung in erfindungsgemäßer Ausführung,

Figur 4

ein Schaltschema eines zweistufig bestromten Starters mit einer Reihenschluss-Erregerwicklung in erfindungsgemäßer Ausführung,

Figur 5

ein zweites Schaltschema eines zweistufig bestromten Starters in erfindungsgemäßer Ausführung und

Figur 6

ein drittes Schaltschema eines zweistufig bestromten Starters in erfindungsgemäßer Ausführung, wobei die Erregerwicklung des Startermotors teilweise als Reihenschlusswicklung und teilweise als Nebenschlusswicklung ausgebildet ist.

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FIG. 1

a schematic diagram of a push-screw starter with a series winding and a shunt winding in the stator,

FIG. 2

a circuit diagram of a single-stage energized starter in a conventional design with a series-wound winding and optionally an additional shunt winding,

FIG. 3

a circuit diagram of a single-stage energized starter with a series-closure exciter winding in accordance with the invention,

FIG. 4

1 is a circuit diagram of a two-stage energized starter with a series-closure exciter winding according to the invention;

FIG. 5

a second circuit diagram of a two-stage energized starter in the inventive design and

FIG. 6

a third circuit diagram of a two-stage energized starter according to the invention, wherein the field winding of the starter motor is partially formed as a series winding and partly as a shunt winding.

Embodiments of the invention

FIG. 1 schematically shows the mechanical structure of the starter 10 according to the invention in the embodiment as a push-screw drive starter for an internal combustion engine. The starter 10 has a starter motor 12, the output shaft 14 has a coarse thread 16 which cooperates with a corresponding female thread in a driving shaft 18. Alternatively, the output shaft 14 is driven via an unillustrated, intermediate planetary gear. The Mitnehmerschaft 18 is fixedly connected to the outer ring of a freewheel ring 20, the inner ring carries a pinion 22. The pinion 22 and the freewheel 20 are on the output shaft 14 to a Stop 24 mounted axially displaceable. The pinion 22 is thereby meshed in a ring gear 26 of an internal combustion engine, not shown. The axial displacement takes place with the aid of a switching device shown in detail in the following figures in the form of a relay arrangement 28, which engages via a deflection lever 29 and a Einspurfeder 32 on the freewheel 20. As a voltage source 34 of the arrangement is a battery which is grounded with its negative terminal 31 and is connected with its positive pole 30 on the one hand directly and on the other hand via a Zündstartschalter 36 with the relay assembly 28. About the relay arrangement, a field winding 37 is supplied with a series winding 38 and a shunt winding 39, which are connected via brushes 40 and 42 and via the collector 44 of the motor, or directly to ground. The armature of the starter motor 12 is denoted by 46, its stator 48.

FIG. 2 shows a circuit diagram of a single-stage energized starter in a conventional design. In this case, the positive pole 30 of the voltage source is connected on the one hand via the ignition start switch 36 and a connection 50 and on the other hand directly to an engagement relay 49. This comprises a holding winding 52 and a pull-in winding 54 which have the same winding sense, are wound on the same core and both are connected to the connection 50 with a winding end. The other winding end of the holding winding 52 is connected to the negative pole 31 and to ground, the corresponding other winding end of the pull-in winding 54 is connected via the series winding 38 and the armature 46 of the starter motor 12 to the negative pole 31 and to ground. In the case of the use of a double-tail exciter winding for the starter motor 12, a shunt winding can be used in basically known manner 39 of the series winding 38 and the armature 46 of the starter motor are connected in parallel.

The holding winding and the pull-in winding of the engagement relay 49 actuate together a normally open contact 56 of the engagement relay, via which the starter motor 12 is directly connected to the positive pole 30 as soon as the relay armature is retracted and the pinion 22 is meshed with the ring gear 26.

The holding winding 52 and the pull-in winding 54 take in this known arrangement together the work of the meshing of the pinion 22 in the ring gear 26 on the engine and at the same time the function of switching the main current for the starter motor 12. In this case meets a tooth of the pinion 22 to a gap in the ring gear 26 so only a small force is necessary for meshing. If when meshing a tooth of the pinion 22 meets a tooth of the ring gear 26, so when meshing the in FIG. 1 shown Einspurfeder 32 tensioned and performed with the support of the Einspurvorgang.

FIG. 3 shows an inventive circuit diagram of a single-stage energized starter, with the above-described risk of damage to the teeth between starter and engine is corrected. The circuit arrangement corresponds in terms of the structure with a Einspurrelais 49 and its connection to the DC network 30, 31 in principle those in FIG. 2 However, in this arrangement, the relay contact 56 at power-on not the full motor current but it is initially only the energization of the partial windings a and f of the six partial windings a, b, c, d, e and f of the field winding 37th Die Stator der Startermotors 12 is six-pole, at startup, however, only pole pair are energized with two diametrically opposite poles on the stator, while the remaining series winding part windings b, c, d and e are switched on later. The starter is controlled via the ignition switch 36 and the terminal 50 and in this case the positive pole 30 of the DC voltage source connected to the same direction windings of the holding winding 52 and the pull-in winding 54, so that the engagement relay 49 moves. In this case, a current flows to the armature 46 of the starter motor 12 via the low-impedance pull-in winding 54 to the armature 46 and from there via the partial windings a and f of the field winding 37 to the ground and the negative pole 31 of the DC voltage source. Due to the initial current through the starter motor 12, the pinion 22 is displaced in the direction of the toothed rim 26. In doing so, the in FIG. 1 drawn entrainment spring 32 compressed in support of the Einspurvorgangs. The normally open contact 56 of the engagement relay 49 is actuated after the engagement relay has almost fully retracted so that it connects the starter motor 12 directly to the positive pole 30 of the DC voltage source.

Of the six partial windings af and the associated poles of the field winding, initially only the two partial windings a and f are energized. Simultaneously with their energization, however, the winding 58 of the switching relay 60 is energized via the normally open contact 56 of the contactor 49, which now also retracts and closes with a delay of approximately 20-80 ms from the start of excitation his normally open contact 62 and thereby, also via the armature 46th , the remaining partial windings b, c, d and e energized and energized the associated poles. Thus, the starter motor 12 reaches its full power for cranking the engine at a time when the pinion 22 in the ring gear 26th Fully meshed and the risk of damage is avoided.

FIG. 4 shows a circuit arrangement for two-stage energization of the starter motor 12. In place of the Einspurrelais 49 in FIG. 3 enters a Einspurrelais 64 with a normally closed contact 66 and a normally open contact 68. The normally closed contact 66 with the pull-in winding 54 and the holding winding 52 are connected via a pilot relay 70, the connection point 50 and the ignition switch 36 to the positive pole 30 of the DC voltage source. The second terminal of the holding winding 52 is grounded and the negative pole 31 of the DC voltage source, while the second terminal of the pull-in winding 54 is connected on the one hand via the starter motor 12 and on the other hand via the winding 58 of a switching relay 60 to ground and to the negative pole 31 of the DC voltage source. Here, again, only the two partial windings a and f of the excitation winding 37 are energized, so that adjusts a Verdrehstrom for the starter motor 12 during the Einspurens on these partial windings and the pull-in winding 54 of the engagement relay 64, which after closing the normally open contact 68 via this directly from the positive pole 30 to the motor 12 flows. With the partial energization of the starter motor 12, the winding 58 of the switching relay 60 is energized via the connection point 50q, whereby the relay moves in and closes the normally open contact 62 with a delay of approximately 20-80 ms from the start of excitation and thus the next two partial windings b and e of Energized energizing coil and thus increases the performance of the starter motor 12.

By closing the normally open contact 62 of the switching relay 60, the winding 76 is now also via the connection point 50r a further switching relay 72 energized, so that this retracts and closes with a further delay of about 20-80 ms from the start of excitation of the winding 76 its working contact 74, via which the last two partial windings c and d of the excitation winding 37 are energized and thus the starter motor 12 has reached full capacity. Opposite the circuit in FIG. 3 Here, the power increase is carried out in three instead of two switching stages and thus the mechanical stress of the pinion-sprocket connection to the engine even more evenly executed.

In this embodiment, the two windings 52 and 54 of the Einspurrelais 64 opposite winding direction, wherein the holding winding 52 has a significantly higher number of turns than the pull-in winding 54 and is energized with a sufficiently large current to alone despite the opposite direction of the indenting winding 54 Einspurvorgang of Ritzel 22 to accomplish. The pull-in coil 54 advantageously dampens the dynamics of the meshing movement and at the same time supplies a sufficiently high exciter current to the series-connected partial windings a-f of the starter motor 12 in order to slightly turn it and facilitate or enable the meshing process. In this arrangement, a Einspurfeder additionally be used to assist the Einspurvorgangs.

The use of a pilot control relay 70 is for the operation of the circuit according to FIG. 4 not mandatory, the Einspurrelais 64 can also analogous to the circuit in FIG. 3 be energized directly via the ignition switch. On the other hand, it lies Motor current in the first Bestromungsphase on the pull-in winding 54 in the order of up to 200 A, so that at least for high-performance starter motors in the first stage of energization, the use of a pilot control relay to bypass the Zündstartschalters 36 is appropriate.

FIG. 5 shows a variant of the circuit according to FIG. 4 , which differs from the previously described embodiment in that the excitation current for the winding 37 from the beginning of the series connection current is passed over four partial windings a, c, d and f. The switching on of two additional partial windings b and e again takes place via the connection point 50q and the switching relay 60 with a delay of approximately 20-80 ms from the beginning of the excitation. It is therefore again a two-stage energization of the partial windings of the excitation winding 37 analogous to FIG. 4 However, four partial windings are already energized in the first switching operation. This is made possible in particular by the use of the pilot control relay 70, which relieves the ignition start switch 36 and allows the higher initial energization of the starter motor, provided that the mechanical load of the pinion-toothed ring connection is not too high during meshing.

FIG. 6 shows a further circuit variant for the energization of the partial windings af the exciter winding 37. In this embodiment, again in analogy to the embodiment according to FIG FIG. 5 an initial energization of four partial windings a, c, d and f of the excitation winding 37. The connection of the two other partial windings b and e is not carried out in series with the armature 46 but in shunt across the switching relay 60, the winding 58 in the same manner as in the Circuit arrangement according to FIG. 5 is energized via the connection point 50q simultaneously with the armature 46 and the partial windings of the field winding 37 energized in series connection. The likewise delayed by about 20-80 ms from the start of excitement closing the normally open contact 62 now connects the partial windings b and e in shunt to armature 46 to ground and thus allows a Doppelschlusserregung the starter motor 12. With this variant, in particular the amount of idle speed of Set starters regardless of the size of the main starter current.

The inventive design of the starter for an internal combustion engine is particularly suitable for launch systems, which have the necessary space for one or two additional relays. In this case, the realization of the circuit arrangement with little additional effort is possible because the circuit can be performed with existing components and thereby the life of the starter can be extended. Furthermore, the inventive division of the excitation winding 37 is not limited to a six-pole version of the starter. It is preferably suitable for all pole numbers of the stator 48, in which the spatial position of the pole pairs does not deviate too much from a diameter orientation. This is especially true for stator designs with six, eight, ten or twelve poles.

Claims (7)

1. Starter for an internal combustion engine, having a starter motor (12) which can be connected to a DC voltage supply system (30, 31) by means of a switching apparatus (27) and of which the stator (48) has a field winding (37) which is subdivided into a plurality of winding elements (a-f) which can be connected selectively to the DC voltage supply system (30, 31) by the switching apparatus (27) such that they are offset from one another with respect to time, characterized in that the stator (48) of the starter motor (12) is of six-pole design with six winding elements (a-f) of the field winding (37) on three pole pairs, it being possible for a first even-numbered group of winding elements (a, f) of the field winding (37) to be connected to the DC voltage supply system (30, 31) by means of a first switching element (49, 64) of the switching apparatus (27) and it being possible for at least one further even-numbered group of winding elements (b, c, d, e) to be connected with a delay by means of at least one further switching element (58, 60, 72).
2. Starter according to Claim 1, characterized in that a first even-numbered group of winding elements (a, f; c, d) of the field winding (37) can be connected to the DC voltage supply system (30, 31) in series with the armature (46) of the starter motor (12) by means of a first switching element (49, 64) of the switching apparatus (27), and at least one further even-numbered group of winding elements (b, e) can be connected with a delay by means of at least one further switching element (58, 60, 72).
3. Starter according to Claim 1 or 2, characterized in that all the switching elements (28, 49, 60, 64, 72) of the switching apparatus (27) are in the form of a relay.
4. Starter according to one of the preceding claims, characterized in that a first even-numbered group of winding elements (a, f) of the field winding (37) can be connected to the DC voltage supply sytem (30, 31) by means of an engagement relay (49, 64) of the switching apparatus (27).
5. Starter according to one of the preceding claims, characterized in that a first even-numbered group of winding elements (a, f) of the field winding (37) can be connected to the DC voltage supply system (30, 31) in series with the armature (46) of the starter motor (12) by means of a first switching element (49, 64) of the switching apparatus (27), whereas a second even-numbered group of winding elements (b, e) can be connected with a delay in relation to the first group of winding elements (a, f), and a third group of winding elements (c, d) can be connected with a delay in relation to the second group of winding elements (b, e).
6. Starter according to one of the preceding claims, characterized in that a first even-numbered group of winding elements (a, f, c, d) of the field winding (37) can be connected to the DC voltage supply system (30, 31) in series with the armature (46) of the starter motor (12) by means of an engagement relay (49, 64) of the switching apparatus (27), and at least one further even-numbered group of winding elements (b, e) can be connected with a delay likewise in series with the armature (46) by means of at least one further switching element (58, 60, 72).
7. Starter according to one of the preceding claims, characterized in that at least one even-numbered group of winding elements (b, e) of the field winding (37) can be connected with a delay to the other groups of winding elements (a, f; c, d) in parallel to the armature (46) of the starter motor (12) by means of a switching element (58) of the switching apparatus (27).

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