EP2286429B1 - Engaging relay for starters of internal combustion engines - Google Patents

Description

The invention relates to an engagement relay for starters of internal combustion engines according to the preamble of claim 1.

State of the art

Such contact relays usually have a pull-in winding and a holding winding. According to the DE 10 2004 032 373 A1 In this case, the starter pinion is initially slid axially into the ring gear of the internal combustion engine by energizing the two windings while simultaneously being slowly rotated by the starter motor. At the end of the feed path, the relay armature then actuates a changeover contact with which the pull-in winding is switched off and the starter motor is connected directly to the electrical power supply.

A disadvantage here is that the dynamic behavior of the engagement relay is influenced when the starter pinion meshes with the holding winding of the relay. This can lead to Einspurproblemen the starter pinion by the pinion too little twisted in too-fast toes or in too slow toads the pinion is too much twisted, which then leads to the toothed ring of the machine to a tooth-on-tooth position. Only with the full torque of the starter motor shoots then the pinion in the sprocket with correspondingly high wear and loud noise.

From the DE 198 14 504 A1 is an engagement relay is known in which the starter pinion is vorgespurt of the relay winding with optimized dynamics and in which is switched simultaneously via the normally closed contact of the relay, the starter motor for smooth start via a resistor to the electrical supply. After meshing, the resistor is then switched off via the changeover contact of the relay and the starter motor is switched directly to the electrical supply. In this known solution, the resistance is a meandering wound resistance wire. It is aligned with its connection ends to the changeover contact and placed around the relay winding outside. By this arrangement of the resistor, this acts at the same time as an inductive winding. This leads to an undesirable influence on the magnetic dynamics of the engagement relay.

From the FR 10 22 487 the production of a resistor is known which is largely formed electromagnetically neutral.

The present solution seeks to make the dynamics of the contactor as independent as possible of the series resistor of the starter motor, but still to integrate it in the engagement relay.

Disclosure of the invention

An engagement relay with the characterizing features of claim 1 has the advantage that on the one hand the Einspurzeit the starter pinion is only determined or regulated by a corresponding dimensioning of the relay winding by the largely electromagnetically neutral design of the resistance element and that on the other hand, the gentle turning of the starter motor during Einspurvorgang exclusively done by the dimensioning of the resistive element A mutual vote of the two components is therefore no longer necessary. By a clever structural design and arrangement of the resistance element on the support body of the relay winding can also be avoided larger outer dimensions of the relay.

The measures listed in the dependent claims, advantageous embodiments and developments of the features specified in claim 1.

Thus, the two mutually parallel conductors and the end connection of a wound through and correspondingly bent Widerstansdraht are formed in the simplest way. In addition, a bare Widerstansdraht is preferably used for the preparation of the resistive element whose mutually parallel conductors are fixed at a distance from each other on the winding support of the relay winding. A spatially optimal arrangement of the resistance element with the shortest possible connection connections results from its arrangement on the changeover contacts facing end side of the winding support. In order to avoid additional space requirement, the resistance element is arranged concentrically within an end region of the relay winding in a frontally open annular chamber of the winding carrier. In an expedient manner, the two conductors of the resistance element arranged around the longitudinal axis of the relay are concentric with one another and spaced apart by a web projecting axially at the bottom of the annular chamber and embedded in a potting compound filling the annular chamber and / or closed by a cover.

Alternatively, the resistance element can also be integrated in a preassembled state in the engagement relay. For this purpose, the resistance element is fixed in a further development of the invention under a cover, preferably injected into plastic at least in several plastic sections, which can be used as a prefabricated component in the annular chamber of the winding support and having a free conductor ends receiving breakthrough. For pre-assembly while the two bare conductor of the resistance element on the back of the lid are arranged concentrically parallel to each other and spaced apart by an integrally formed on the cover, axially projecting web. In the aforementioned embodiments of the resistance element, the two mutually parallel conductors are expediently arranged at an angle of α> 180 ° and preferably of α <360 ° around the longitudinal axis of the relay, in particular with uniform curvature.

The size of the resistor element is primarily dependent on the starter motor. So it may be necessary that the two leaders of the Resistor element must be arranged with more than one complete turn around the longitudinal axis of the relay around. For this case, the two conductors are bent at an angle of α <360 ° in the region of their axially angled free ends by more than one conductor thickness, preferably by at least two conductor thicknesses to an axially offset bend in the simplest way. In their arrangement on the front side of the winding support, it is also expedient if the two conductors extend at an angle α> 360 ° in several turns spirally at a distance from each other. Another alternative with little space is obtained by the two mutually parallel conductors at an angle α> 180 ° are fixed or injected threadably about the longitudinal axis of the relay in a Isolierstoffhülse, which is preferably axially insertable on the inside of the winding support.

Brief description of the drawings.

• Figur 1 einen Längsschnitt durch ein Einrückrelais für Starter von Brennkraftmaschinen,
• Figur 2 die Schaltung einer Startanlage mit dem Einrückrelais aus Figur 1,
• Figur 3 ein ersten Ausführungsbeispiel eines Widerstandselementes in raumbildlicher Darstellung,
• Figur 4 einen vergrößerten Längsschnitt des Wicklungsträgers aus Figur 1 und Figur 4a eine Variante zu Figur 4 mit Vergussmasse,
• Figur 5 einen Deckel mit eingespritztem Widerstandselement nach Figur 3 in raumbildlicher Darstellung,
• Figur 6 eine Variante des Deckels nach Figur 5 mit dem Widerstandselement,
• Figur 7 ein am Deckel vormontiertes Widerstandselement nach Figur 2 in raumbildlicher Darstellung,
• Figur 8 ein zweites Ausführungsbeispiel des Widerstandselementes in raumbildlicher Darstellung,
• Figur 9 ein drittes Ausführungsbeispiel des Widerstandselementes in schematischer Darstellung,
• Figur 10 ein viertes Ausführungsbeispiel des Widerstandselementes in einer Isolierstoffhülse in raumbildlicher Darstellung,
• Figur 11 ein Widerstandselement mit U-förmig gebogenen Leitern und
• Figur 12 zeigt ein Flussdiagramm für den Magnetfluss im Einrückrelais bei einem Startvorgang.

The invention will be explained in more detail below by way of example with reference to FIGS. Show it:

• FIG. 1 a longitudinal section through an engagement relay for starters of internal combustion engines,
• FIG. 2 the circuit of a starting system with the contactor FIG. 1 .
• FIG. 3 A first embodiment of a resistive element in a spatial representation,
• FIG. 4 an enlarged longitudinal section of the winding carrier FIG. 1 and FIG. 4a a variant too FIG. 4 with potting compound,
• FIG. 5 a lid with injected resistance element after FIG. 3 in spatial representation,
• FIG. 6 a variant of the lid after FIG. 5 with the resistance element,
• FIG. 7 a pre-assembled on the cover resistance element FIG. 2 in spatial representation,
• FIG. 8 A second embodiment of the resistance element in a three-dimensional representation,
• FIG. 9 A third embodiment of the resistance element in a schematic representation,
• FIG. 10 A fourth embodiment of the resistance element in a Isolierstoffhülse in three-dimensional representation,
• FIG. 11 a resistor element with U-shaped bent conductors and
• FIG. 12 shows a flow chart for the magnetic flux in the engagement relay at a startup.

Embodiments of the invention

FIG. 1 shows the structural design of a designated 10 engagement relay for the starting system of an internal combustion engine in motor vehicles. The engagement relay 10 has a relay winding 11 on a winding support 12 made of plastic, which is mounted on a magnetic core 13. The relay winding 11 is inserted in a metallic housing 14, in the front, open end of the magnetic core 13 is added. At the bottom of the housing 14, an armature 15 of the relay is axially guided in an opening, which dips into the relay coil 11. In a central bore of the armature 15, a plunger 16 is fixed, whose head-side end has a so-called paddle 17 for receiving a Einrückhebels for a starter pin, not shown. In a through hole of the magnetic core 13, a shift rod 18 is guided by means of an insulating sleeve 19, wherein the front end of the shift rod 18 at a distance from the end of the plunger 16 is opposite. At the rear end of the shift rod 18 acting as a changeover 20 contact bridge is axially displaceable, on the one hand with unrecognizable rest contacts on an insulating plate on the back of the magnetic core 13 cooperates and on the other hand, two mating contacts 20a is opposite, which are mounted in a switch cover 21, which is fixed on the magnetic core 13 by a housing edge 14 a at the upper, open end of the housing 14. The two mating contacts 20a are screwed as terminals 30 and 45 in the switch cover 21. In an axial recess 15a of the armature 15, an armature return spring 23 is arranged, which cooperates in a known manner with a contact return spring 24 and a contact pressure spring 25. All three springs are biased so that the in FIG. 1 shown rest position.

During a starting process, when the starter pinion meshes with the ring gear of the internal combustion engine, the starter motor is slightly rotated via a resistance element 26. This resistance element 26 is integrated in the engagement relay 10 by being fixed under the magnetic core 13 on the changeover contact 20 facing end side of the winding support 12.

FIG. 2 shows a starter motor 31 is connected by a vehicle battery 32 as an electrical power supply via the terminals 30 and 45 of the contactor 10 directly from the changeover 20 of the contactor 10 to positive potential. The positive potential of the vehicle battery 32 is also located at a start switch 33, which is followed by a starter relay 34. Via the switching contact 34a of the starting relay 34, the positive potential of the vehicle battery 32 is switched to the engagement relay 10. In engagement relay 10, the positive potential on the one hand to the grounded relay winding 11 and on the other hand via the normally closed contact 20 b to the resistance element 26 and from there via the terminal 45 to the starter motor 31. At the end of the anchor travel is via the shift rod 18 of the contactor 10 of the normally closed contact 20 b of the contact bridge 20 of the changeover contact is opened and the countercontact 20a is closed. As a result, the resistance element 26 is switched off and the starter motor 31 is connected directly to the electrical supply at the end of the engagement path.

In a first embodiment is in FIG. 3 the resistance element 26 is shown as largely electromagnetic neutral winding. It consists of two mutually parallel conductors 27a, 27b, which is arranged around the longitudinal axis x of the engagement relay 10 around and whose ends are connected by an end connection 27c with each other in series. The two conductors 27a, 27b of the resistance element 26 and their end connection 27c consist of a continuous and correspondingly bent resistance wire, which in the present embodiment has a diameter of 2 mm and resistance R of approximately 1.5 Ω. The resistance wire made of a copper-nickel alloy has two angled in the axial direction of the contactor 10 free terminal ends 27d. The two mutually parallel conductors 27a, 27b are here with a uniform curvature in An angle α of about 350 ° about the longitudinal axis x of the engagement relay 10 around.

In FIG. 4 can be seen that the resistance element 26 of FIG. 3 on the upper end side of the winding carrier 12 shown enlarged in longitudinal section in a molded there, frontally open annular chamber 35 of the winding support 12 is inserted. The two concentric parallel conductors 27a, 27b are spaced apart in the annular chamber 35 fixed by being spaced apart by a at the bottom of the annular chamber 35 axially projecting web 35a. The annular chamber 35 is closed by a plastic cover 36 and fixed by a serving for receiving the armature 15 brass sleeve 37. The terminal ends 27 d of the resistance element 26 are guided through an axial collar 38 of the winding support 12.

Since the resistance element 26 is made of a bare resistance wire, its two conductors 27a, 27b can alternatively be embedded in a sealing compound 28 filling the annular chamber 35 as an alternative to the plastic cover 36, as shown in FIG FIG. 4a is shown. Optionally, the resistance element 26 also initially embedded in potting compound and then the annular chamber 35 are closed by a cover 36.

FIG. 5 shows in a three-dimensional representation of a plastic lid 36 a, below which the resistance element 26 from FIG. 3 is fixed by being injected there in a plastic material 39. In this case, the plastic material 39 for a holding tool of the plastic lid 36 a plurality of recess 40. The free conductor ends 27d are passed through an opening arranged in the collar 38 of the plastic lid 36a.

FIG. 6 shows one too FIG. 5 alternative embodiment of the plastic cover 36a turned upwards in a spatial representation, in which the resistance element 26 of FIG. 3 is embedded on the underside of the plastic lid 36a only in a plurality of mutually uniformly spaced plastic portions 39a.

In FIG. 7 is a spatial representation of a preassembled unit from the plastic lid 36a and the resistance element 26 recognizable. There, the two bare conductors 27a, 27b of the resistance element 26 on the back of the plastic lid 36a concentric with each other extending parallel to each other by an integrally formed on the cover, axially projecting web 41 from each other. It can also be seen there that the two free ends 27d of the conductors 27a, 27b of the resistance element 26 in the collar 38 of the plastic cover 36a are guided through an opening 42 to the outside. The pre-assembled in this way resistance element 26 is then according to FIG. 6 through the plastic sections 39a or by the almost complete embedding in the plastic material 39 according to FIG FIG. 5 fixed to finally into the annular chamber 35a of the bobbin according to FIG. 1 to be used.

In FIG. 8 a further embodiment of the resistive element is shown and designated 26a. Here, the two concentric parallel conductors 27a, 27b arranged in almost two complete turns about the longitudinal axis x of the contactor 10 with uniform curvature. At the end of the first turn there are the two conductors 27a, 27b bent in the region of their axially bent free ends 27d by more than one conductor thickness to an axially offset bend 27e. The bend 27e here is about 1.5 times the conductor thickness in order to ensure a sufficient distance between the two turns of the bare conductors 27a, 27b. The end connection 27c of the two conductors 27a, 27b is located there below the offsets 27e. This resistance element 26a is in a correspondingly recessed annular chamber 35 of the winding support 12 according to FIG. 4 used or according to FIGS. 5 and 6 fixed at the bottom of the plastic lid 26a in plastic material 39 or 39a.

FIG. 9 shows a schematic representation of another, designated 26b embodiment of the resistance element 26. There, the two concentric parallel conductors 27a, 27b are arranged in almost two complete turns spirally spaced. Such a resistance element 26b can be in the simplest way on the upper end side of the winding support 12 FIG. 1 Attach. As FIG. 9 shows, while a uniform curvature of the conductors 27a, 27b is not mandatory.

In FIG. 10 is a further embodiment of a resistive element 26c shown spatially. There, the two mutually parallel conductors 27a, 27b at an axial distance from one another with more than one turn (α> 360 °) are threadedly injected about the longitudinal axis x of the contactor 10 in a Isolierstoffhülse 43. Consequently, the resistance element 26c in the insulating sleeve 43 can only be seen by dashed lines, since only the free, axially angled ends 27c on the upper end side of the insulating sleeve 43 emerge from the insulating material of the sleeve. In this embodiment, the dimensions of the insulating sleeve 43 are selected so that they on the inside of the winding support 12 from FIG. 1 is axially usable.

In FIG. 11 is shown as a further embodiment, a resistance element 26d that consists of a continuous resistance wire with a rectangular cross-section in the form of a three / four-turn of the two concentric parallel conductors 27a, 27b. The resistance element 26d is formed with two right-angled bends U-shaped, wherein the two bare conductors 27a, 27b to each other at a distance. This resistance element 26d is also in a corresponding recess on the upper end side of the winding support 12 after FIG. 1 used.

In FIG. 12 is in a time chart of the magnetic flux Φ of the engagement relay 10 off FIG. 1 during one with the circuit arrangement FIG. 2 performed boot process shown. At the time t1, the start switch 33 is closed and the relay winding 11 of the engagement relay 10 is energized via the starter relay 34. With the magnetic flux Φ _RW thus generated, the armature 15 of the engagement relay 10 is retracted until finally at time t2 the changeover contact 20 of the engagement relay 10 is actuated. As a result, the normally closed contact 20b is opened and the mating contact 20a is closed. Up to this time, a metered current flows through the normally closed contact 20b of the contactor 10 and the series-connected resistance element 26 to the starter motor 31. Thus, the starter motor 31 is slightly turned during toe-in of the starter pinion to gently mesh the starter pinion in the ring gear of the internal combustion engine can. At time t3, the resistance element 26 is turned off and the starter motor 31 is replaced now to crank the engine, the full voltage of the vehicle battery 32 via the mating contacts 20a of the changeover 20. After running up the engine is opened again at time t4, the start switch 33 and the startup process is terminated.

In the various embodiments of the resistance element 26 according to FIG. 3 . 8th . 9 . 10 and 11 It can be seen that the mutually parallel conductors 27a, 27b and their terminal ends 27d are not the same length until their end connection 27c. It follows that the magnetic fields of the resistive element 26 forming due to the current flow at the two conductors 27a, 27b do not completely cancel each other out. This leaves a residual magnetic flux .DELTA..PHI..sub.B, which, however, is significantly lower due to the inventive design of the resistance element 26 than in the embodiments according to the prior art. This residual magnetic flux is superimposed on the magnetic flux Φ _{RW of} the relay winding 11 until the normally closed contact 20b is opened. According to FIG. 12 Depending on the current direction in the resistance element 26, this results in a slight weakening or amplification of the magnetic flux Φ _RW by the amount ± ΔΦ.

The invention is not limited to the illustrated embodiments, since the design and arrangement of the resistance element 26 allows numerous alternatives. Thus, instead of a circular or U-shaped design of the resistance element as an oval, polygonal or non-uniform design can be used. It is also possible, instead of a wound through resistance wire, the two parallel conductors 27a, 27b connected as a single conductor with a separately prepared end connection 27c with each other to the resistance element 26 in series. Depending on the load, various known materials for the resistance element 26 can also be used. By fixing the resistance element 26 on the winding support 12 of the contactor 10 is dispensed with a paint insulation of the resistance wire. In addition, a web arrangement between the two conductors 27a, 27b of the resistance element 26 increases the shock and vibration resistance of the resistance wire and in addition, when inserting the resistance element 26 in the annular chamber 35 of the winding support 12, the Head 27a, 27b jammed in the chamber and thus securely positioned for further assembly steps. Instead of the web 35a in the annular chamber 35 after FIG. 4 or the web 41 on the plastic cover 36 after FIG. 5 For example, the resistance element 26 can also be preassembled with separate spacer clips in the annular chamber 35 or on the plastic cover 36a.

Claims (9)

1. Engagement relay (10) for starters of internal combustion engines in which a starter pinion can be initially axially displaced by current being applied to a relay winding (11) and can engage into a ring gear of the internal combustion engine in the event of simultaneous slow rotation, in order to then be driven by the starter motor (31) with full power until the end of the starting process, wherein the engagement relay is designed with a changeover contact (20) which, for slow rotation, connects the starter motor to the electrical power supply by means of a resistance element (26) in the first part of the engagement path and connects said starter motor directly to the electrical power supply at the end of the engagement path, wherein the resistance element (26), as a largely electromagnetic neutral winding with two conductors (27a, 27b) which run in parallel to one another, is arranged around the longitudinal axis (x) of the relay (10), and wherein the ends of the two conductors (27a, 27b) are connected to one another, wherein the two conductors (27a, 27b) and the end connection (27c) of said conductors comprise a continuous and correspondingly bent resistance wire, wherein the conductors (27a, 27b) of the preferably blank resistance wire are fixed to the winding support (12) of the relay winding (11) at a distance from one another, wherein the resistance element (26) is fixed to that end face of the winding support (12) which faces the changeover contact (20), wherein the resistance element (26) is arranged concentrically within the relay winding (11) in a ring chamber (35) of the winding support (12), which ring chamber is open at an end face.
2. Engagement relay according to Claim 1, characterized in that the two conductors (27a, 27b) of the resistance element (26) run concentrically in parallel in relation to one another, are spaced apart from one another by a web (35a) which projects axially from the base of the ring chamber (35) and also are embedded in a potting compound (28) which fills the ring chamber (35) and/or are closed by a cover (36).
3. Engagement relay according to Claim 1, characterized in that the resistance element (26) is fixed beneath a cover (36a), preferably in plastic material (39), is injection-moulded at least into several plastic sections (39a), and in that the cover (36a) can be inserted into the ring chamber (35) of the winding support (12) and has an aperture (42) which receives the free conductor ends (27c).
4. Engagement relay according to Claim 3, characterized in that the two blank conductors (27a, 27b) of the resistance element (26) run in parallel concentrically in relation to one another on the rear face of the cover (36a) and are spaced apart from one another by an axially projecting web (41) which is integrally formed on the cover.
5. Engagement relay according to one of the preceding claims, characterized in that the two conductors (27a, 27b) which run in parallel in relation to one another are arranged at an angle α > 180° and preferably α < 360° about the longitudinal axis (x) of the relay (10), in particular with a uniform curvature.
6. Engagement relay according to one of the preceding claims, characterized in that the two conductors (27a, 27b) are injection-moulded into an insulation sleeve (43), which is preferably axially inserted on the inside of the winding support (12), in the manner of a thread about the longitudinal axis (x) of the relay (10) given an angle α > 360°.
7. Engagement relay according to one of Claims 1 to 5, characterized in that, given an angle α > 360°, the two conductors (27a, 27b) are bent by more than one conductor thickness, preferably by 1.5 conductor thicknesses, to form an axially offset bent portion (27e) in the region of their axially angled free ends (27c).
8. Engagement relay according to one of Claims 1 to 5, characterized in that the two conductors (27a, 27b) run at a distance from one another in a spiral manner in several turns given an angle of α > 360°.
9. Starter for internal combustion engines comprising an engagement relay according to one of the preceding claims.

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