EP1019630B1 - Starting device for internal combustion engines - Google Patents

Abstract

The invention relates to a starting device for internal combustion engines, comprising a starter motor having a pinion which initially engages the toothed ring of the internal combustion engine with a starting signal through an engaging magnet, before the starter motor triggers with full power the starting process. The aim of the invention is to improve engagement of the starter pinion and switching of the starter motor. For this purpose, the starter motor (SM) first drives the starter pinion with a reduced torque by means of the starting signal (st) through a series resistor (Rvor), and the engaging magnet (EM) engages the pinion with the toothed ring of the internal combustion motor. The engaging magnet (EM) then depresses fully the pinion in the toothed ring of the internal combustion engine, and the starter motor (SM) starts the internal combustion engine with full torque through by-passing the series resistor (Rvor).

Description

State of the art

The invention relates to a starting device for internal combustion engines with a starter motor, whose starter pinion first with a starting signal via an engagement magnet in the ring gear engages the internal combustion engine before the starter motor triggers the starting process with full force.

It is envisaged that the starter motor with the starting signal initially via a Series resistor with reduced torque drives the starter pinion and the engagement magnet in the Engages the ring gear of the internal combustion engine. The engaging magnet then presses the starter pinion completely in the ring gear of the internal combustion engine. Finally the starter motor spins Bridging the series resistor by the internal combustion engine with full torque.

A starting device of this type, with the features according to claim 1, part 1, is known from FR 2532690 A1. In this known The starter engagement magnet is activated in such a way that the starter is immediately connected to it the pinion meshes with full force into the ring gear of the internal combustion engine. this leads to Signs of wear or damage to the teeth of the two abutting Parts.

A similar solution is known from Japanese laid-open publication JP 09 177 644.

Furthermore, a starting device is known from DE 30 02 232 C2, in which with the contact of the Ignition switch the engagement magnet is fully controlled, so that the starter pinion with full power strikes against the ring gear of the internal combustion engine if it cannot be engaged directly. This also leads to signs of wear or damage to the teeth of the two abutting parts.

It is an object of the invention to improve a starting device of the type mentioned in the introduction, that engaging the starter pinion in the ring gear of the internal combustion engine and switching the Starter motor can be improved.

This object is achieved according to the invention as defined in accordance with the features of claim 1 in that the starter motor with the starting signal first drives the starter pinion via a series resistor with reduced torque and the Magnet engages the pinion into the ring gear of the internal combustion engine, then the Engagement magnet completely pushes the starter pinion into the ring gear of the internal combustion engine then, with the series resistor bridged, the internal combustion engine by means of the starter motor full torque. The engagement magnet is activated by means of a logic circuit a second controlled semiconductor, in particular a highside smart FET, clocked, until the starter pinion engages in the ring gear of the internal combustion engine.

This results in a two-stage process with a special for the engagement of the starter pinion gentle engagement of the pinion in the ring gear. In the first stage, the starter motor is over the series resistor operated with low torque. At the same time the engagement magnet is by means of the logic circuit is controlled in a clocked manner via a second controlled semiconductor. The twisting of the starter motor makes it easier to find a tooth gap on the one hand and with the clocked one Engagement magnets result in a reduced-speed feed of the starter pinion, so that the Wear is reduced when the starter pinion hits the ring gear of the internal combustion engine becomes. In the second stage, the engagement magnet is fully energized, so that the starter pinion is complete can engage in the ring gear of the internal combustion engine. Then the starter motor becomes full energized and thus turns at full torque.

According to one embodiment, it is provided that the starting signal is fed to a logic circuit which via a first controlled semiconductor, e.g. B. a highside smart FET from the series connection The series resistor and starter motor are charged with reduced current.

With this control, the starter contact of the ignition lock is relieved and when the In addition, a chronological sequence can be introduced for both highside smart FETs, so that the reduced activation of the starter motor at the same time as the engagement magnet is applied can take place or the engagement magnet is only acted upon after the starter motor has started can be.

A forced sequence of the two switching operations can also be achieved by that the second semiconductor is connected in series with the first semiconductor and that after the starter pinion has been engaged, the second semiconductor via the Logic circuit is fully controlled.

The transition from the two stages of engagement and switching of the starter motor can be controlled according to an embodiment in that the engagement of the starter pinion in the ring gear of the internal combustion engine by means of a displacement sensor monitored and the logic circuit is displayed and that the logic circuit depending on the response of the displacement sensor the second Semiconductor switches from clocked operation to continuous operation.

The initiation of the second stage of the starting process is effected by that after pressing the starter pinion into the ring gear of the internal combustion engine the logic circuit a third semiconductor, e.g. a third highside smart FET controls that turns on a power relay and that a contact of the power relay applies full current to the starter motor, the third semiconductors e.g. connected to the plus potential of the supply voltage and in series with the power relay connected to ground or vice versa is switched. With the inclusion of a power relay, that of the engagement magnet controlled contact bridge is not required. The electrical control part for the second stage of engagement and switching of the starter motor can after a further embodiment can also be made so that after the Press the starter pinion into the ring gear of the internal combustion engine Logic circuit controls an N-channel MOS-FET, which turns on the power relay and that a contact of the power relay the starter motor with full Current applied, the power relay at the plus potential of the supply voltage turned on and the N-channel MOS-FET turned on to ground is connected in series with the power relay (LR).

According to one embodiment, it is provided that the logic circuit according to a predetermined time from clocked operation to continuous operation for the engagement magnet switches, then the logic takes over the pure function of a sequence control without feedback. It is assumed that the starter pinion has always found a tooth gap, i.e. is engaged. With the invention Direction of tightening can be made so that the Starter motor, the engagement magnet and, if applicable, the travel sensor one of Electronic part with the logic circuit, the series resistor of the highside smart FETs or the N-channel MOS-FET and the power relay separate starter unit forms, which is connected to the electronic part via three lines.

The electronic part can be separated from the starter and close to the Battery. This usually does not allow the length of the Reduce the protected line (terminal 30) to a minimum. The starter is voltage-free outside of the actual starting process, so that only minor There is a risk of short circuit and fire. In addition, the environmental conditions (Temperature load, vibration acceleration, tightness, etc.) for the Electronics part at this mounting location less critical than directly at the starter, as with known starting devices. The engagement magnet is simpler because it does not Contact bridge must control. This has a space and cost advantage and offers also the possibility to run the starter as a coaxial starter.

The starter also brings a simplified connection technology to the starter, which only has terminals 50 and 45 and possibly a connection for the displacement sensor WS needed. No internal connections are required on the starter. The Control electronics take on the additional functions of two-stage engagement and the gentle toe-in and can perform other functions such as overload and Take overtemperature protection.

Fig. 1

ein erstes Ausführungsbeispiel einer Andrehvorrichtung mit einem über einen Highside-Smart FET geschalteten Leistungsrelais und

Fig. 2

ein zweites Ausführungsbeispiel einer Andrehvorrichtung mit einem über einen N-Kanal-MOS-FET gesteuerten Leistungsrelais.

The invention is explained in more detail with reference to two exemplary embodiments shown in the drawing as circuit diagrams. Show it:

Fig. 1

a first embodiment of a starting device with a power relay connected via a highside smart FET and

Fig. 2

a second embodiment of a starting device with a power relay controlled via an N-channel MOS-FET.

The output from the contact of the ignition lock in a motor vehicle Starting signal is a logic circuit in the starter device according to the invention L is supplied as shown at terminal 50e with st. The logic circuit L gives a control signal for the duration of the start signal st to the output a1, which conducts the highside smart FET T1, the is connected to the plus potential (terminal 30) of the supply voltage U. Thus, the series resistor Rvor and the Starter motor SM supplied with reduced current, so that the starter motor drives the starter pinion with reduced torque. Simultaneously or in time with a delay, the logic circuit L controls the output a2 and is clocked. The clock pulses act on the downstream one via the highside smart FET T2 Engaging magnet EM. This sets the in the series connection shown Switching through the highside smart FET T1 and thus turning the starter motor SM ahead. The engaging magnet EM becomes gentle in this way, i.e. With reduced power consumption, resulting in smooth toe-in and in-line with reduced torque of the starter pinion in the ring gear Internal combustion engine leads. Tracking can be done using a distance sensor WS, e.g. be monitored by a limit switch. Is the starter pinion in the ring gear the internal combustion engine is engaged, then the distance sensor WS gives the input e1 of the logic circuit L a display signal that leads to a control signal leads to the exit a3. The highside smart FET T3 is controlled and controlled switches on the power relay LR, which with its contact t switches the starter motor SM connects directly to the plus potential of the supply voltage U and thus the series resistor R before and the FET T1 bridged. The starter motor SM now drives the ring gear of the internal combustion engine with the starter pinion full torque.

The distance sensor WS can also be omitted if after the initiation of the engagement a predetermined time has elapsed via the control signal on output a2 and the logic circuit L on the output a3 is the power relay LR turns. This forced control requires that the engagement and engagement process was successfully carried out during this time.

As shown in FIG. 1, the starter motor SM and the engaging magnet EM can optionally with the distance sensor WS as starter ST separated from electronic part ET being constructed. Both parts are then via two or three lines interconnected and allow different installation locations in the motor vehicle, as the terminals w, 50 and 45 show.

The structure of the starter device according to FIG. 2 differs from that of FIG Fig. 1 only through the circuit for the power relay LD, which has a cheaper N-channel MOS-FET T4 is turned on. This N-channel MOS FET T4 is connected to the ground potential and to the positive potential of the Supply voltage U connected power relay LR connected in series. The control takes place via the output a3 of the logic circuit L with the correct control potential.

1 with the third highside smart FET T3 Control via output a3 and the other control potential required for this. The highside smart FET T3 is at the plus potential of the supply voltage U switched on and with the one connected to ground potential Power relay LR connected in series.

The control sequence of the two starting devices according to FIGS. 1 and 2 is however identical.

Claims (8)

1. Starting device for internal combustion engines, having a starter motor whose starter pinion initially meshes with the ring gear of the internal combustion engine using a starting signal by means of an engagement magnet before the starter motor triggers the starting process with full force, and using the starting signal (st) the starter motor (SM) first drives the starter pinion by means of a series resistor (Rvor) with reduced torque, and the engagement magnet (EM) meshes with the ring gear of the internal combustion engine, the engagement magnet (EM) then pressing the starter pinion completely into the ring gear of the internal combustion engine and the starter motor (SM) turning the internal combustion engine with full torque by pressing the series resistor (Rvor), characterized in that a logic circuit (L) actuates the engagement magnet (EM) in a clocked fashion, by means of a second actuated semiconductor, in particular high-side smart FET (T2), until the starter pinion meshes with the ring gear of the internal combustion engine.
2. Starting device according to Claim 1, characterized in that the starting signal (st) is fed to the logic circuit (L) which applies a reduced current to the series circuit comprising series resistor (Rvor) and starter motor (SM) via a first actuated semiconductor, in particular high-side smart FET (T1).
3. Starting device according to Claim 2, characterized in that the second semiconductor (T2) is connected in series with the first semiconductor (T1), and in that, after the meshing of the starter pinion, the second semiconductor (T2) is energized completely via the logic circuit (L).
4. Starting device according to one of Claims 1 to 3, characterized in that meshing of the starter pinion with the ring gear of the internal combustion engine is monitored by means of a displacement sensor (WS) and indicated to the logic circuit (L), and in that the logic circuit (L) switches over the second semiconductor (T2) from the clock operating mode to continuous operating mode as a function of the response of the displacement sensor (WS).
5. Starting device according to one of Claims 1 to 4, characterized in that, after the engagement of the starter pinion in the ring gear of the internal combustion engine, the logic circuit (L) actuates a third semiconductor, in particular high-side smart FET (T3), which switches on a power relay (LR), and in that a contact (r) of the power relays (LR) applies the full current to the starter motor (SM), the third semiconductor (T3) being connected to the positive potential of the supply voltage (U) and being connected in series with the power relay (LR) which is connected to earth.
6. Starting device according to one of Claims 1 to 4, characterized in that, after the engagement of the starter pinion in the ring gear of the internal combustion engine, the logic circuit (L) actuates an N-type channel MOS-FET (T4) which switches on a power relay (LR), and in that a contact for the power relay (LR) applies the full current to the starter motor (SM), the power relay (LR) being connected to the positive potential of the supply voltage (U), and the N-type channel MOS-FET (T4) which is connected to earth being connected in series with the power relay (LR).
7. Starting device according to one of Claims 1 to 6, characterized in that the logic circuit (L) switches over from the clock operating mode to continuous operating mode for the engagement relay (EM) after a predefined time.
8. Starting device according to one of Claims 1 to 7, characterized in that the starter motor (SM), the engagement magnet (EM) and if appropriate the displacement sensor (WS) form a starter unit (ST) which is separated from the electronic part (ET) with the logic circuit (L), the series resistor (Rvor), the high-side smart FETs (T1, T2, T3) and/or the N-type channel MOS-FET (T4) and the power relay (LR), and which is connected to the electronic part (ET) via three lines.

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