DE2142938A1 - Electric starting system for internal combustion engines - Google Patents

Description

Patent attorney Karl A. Bröse

Dipl.-Ing.

D-8023 monks - PuUath Wieeerdr.2j.Md «.793» 70.7931782

vln / By Munich-Pullach, August 26, 1971

Paris file 4645-A

THE BENDIX CORPORATION, Executive Office, Bendix Center, Southfield, Michigan 48075, Michigan, USA.

Electric starting system for internal combustion engines

The invention relates to an electric starting system for starting an internal combustion engine that has a battery, a starter motor, a starting solenoid and an ignition switch, to connect the battery to the starter solenoid which, when energized, couples the starter motor to the machine and the battery to the starter motor to start the machine. The invention particularly relates to an improved electrical Starting system that prevents the starting motor from being energized when the engine or prime mover of a vehicle is in operation and / or when an unsuccessful attempt to start the machine has been made.

There has long been a problem with coupling an electric starter motor to an internal combustion engine prevent if only one of the devices listed above is in operation to control the machine, the starter motor and / or the

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to protect orderly transmission from destruction. For example, if the starter motor is running while the machine is running running, elements of the starter arrangement, in particular the gearbox, can be destroyed. Even if the machine does not run and the electric motor is not coupled to the machine, the motor, the machine and / or the gearbox Destroyed if an attempt is made to run the starter motor restart (and the gearbox) if the starter motor is still rotating from a previous attempt to start.

Attempts have already been made to design starter systems so that operation of the starter system is prevented when the engine is running, but this design did not include the restart problem. The known systems did not use any control signals that the machine e.g. the oil pressure, the Generator output variable and / or assigned to the machine revolution are. In the known starter systems, there is no excitation of the starter under any undesirable operating conditions prevented and no control signals are used that originate from electrical parameters of the solenoid, which represents the electromechanical key link in a starter control system.

To excite the starter motor in all undesirable conditions to prevent, in particular in the case of renewed starting conditions, an electronic switch circuit arrives according to the invention for the application that has the ability to remember an attempt to start the machine, in combination with a manually operated ignition switch.

The electronic starting system is characterized in that it is remembered that the solenoid was energized by detects the voltage generated by the collapsing field of Startersolenoids when the starter solenoid is de-energized and then re-energizing the starter Sole noids prevents until the ignition switch is in the "off" position

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moved for a certain period of time.

"This is an object of the present invention, a renewed one "Crazy of the starter motor for internal combustion engines for so long prevent the ignition switch from being turned "off" for a specified period of time.

It is also an object of the invention to provide an electrical system for a motor vehicle which in a suitable manner prevents the electric starting motor from being actuated when the engine is running.

It is also an object of the invention to provide an improved electrical Starting system for starting an internal combustion engine create.

The invention is also looking for an electrical starting system with one to create an electronic switch circuit that controls the flow of current from a battery to an electric starter motor Dependence on a voltage is prevented by the collapsing electromagnetic field of a starter solenoid is generated when the starter solenoid is de-energized.

it is the object of the invention to provide an electronic switch circuit to create that works with a voltage due to the collapsing electromagnetic field a coil is induced.

Another object of the invention is to provide a starter blocking system which only applies to the electric Starter system components responds and not to the machine components or machine parts.

Further advantages and elements of the invention emerge from the following description of exemplary embodiments with reference to the drawings.

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BATH ORIGINAL

These show:

1 'is a block diagram of a starting system for an internal combustion engine;

2 shows a block diagram of an electrical control circuit for an electrical Starting system of an internal combustion engine; and

.Fig.3 schematically a 'circuit diagram of a preferred Embodiment of a control circuit for the electrical starting system of an internal combustion engine.

Figure 1 shows a block diagram of an electrical starting system of an internal combustion engine, in which the subject of the present invention is applied. The solid lines between the blocks represent electrical connections while the dashed lines represent mechanical connections and / or relationships between the blocks. One Power supply 1 supplies the starter solenoid 5 and the ignition circuit 7 with energy and supplies it via a control circuit 9 likewise the starter motor 3 via the switch 2 with electricity which is operated by the starter solenoid 5. The starter solenoid 5 can mechanically couple the starter motor 3 to the internal combustion engine 4, so that when electrical power is supplied to the starter motor 3, the machine is started. When the machine- once runs, it supplies a generator 6 with sufficient current and this generator also supplies the power supply 1 Energy. In general, the power supply 1 is represented by a battery which is recharged by the generator 6 will.

FIG. 2 shows the electrical block diagram in greater detail for the starting system of the fascine. The power supply 1 is on the ignition circuit 7 and to the starter solenoid 5 via a me-

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mechanical switch 10 coupled. The mechanical switch 10 conducts current to a first electronic switch circuit 30 and also to a second electronic switch circuit. The first electronic switch circuit 30 can be brought into an "ON" state and an "OFF" state , wherein this state is controlled by the second electronic switch circuit 20 and also by the position of the mechanical switch 10. When the first electronic switch circuit 30 is brought into the ON state, the starter solenoid 5 is energized. The second electronic switch circuit 20 can also assume an ON and OFF state, which is controlled by the de-energization of the solenoid 5 and the position of the mechanical switch 10. If the second electronic switch circuit 20 is in the ON state, then the first electronic switch circuit 30 is in the OFF state and vice versa. Accordingly, when the second electronic switch circuit 20 is in the ON state, the starter solenoid cannot be energized.

FIG. 3 illustrates the manner in which the first electronic switch circuit 30 and the second electronic switch circuit 20 are energized, de-energized and re-energized in conjunction with the mechanical switch 10 to supply Provide electrical power to the solenoid 5 only at the appropriate and proper time. The mechanical switch 10 is a typical three-position ignition switch with the circuit connections A, B, C and D. The mechanical switch 10 is in the ON position shown with the battery 1 connected to the terminals B and C is connected. In the starting position (dashed lines) the mechanical switch 10 connects the battery 1 to the terminals B, C and D, while in the OFF position - (dashed line Lines) the mechanical switch completely disconnects the power supply from connections B, C and D.

To the terminal D, the first electronic switch circuit 30 is connected, which consists of a first transistor 34, a

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Resistor 35, a second transistor 32 and first and second diodes 31 and 33 consists. The first transistor is preferably a PHP type, the emitter of which is connected to the connection D and the collector of which is connected to one end of the starter solenoid 5. The second transistor 32 is in forthcoming 'ferred way of HPIT type whose "" -m mitter is connected to the common connection point 49 u: .d its base connected to one of the series connected diodes 31 and 33 and whose collector is connected is connected to the base of the first transistor 34 via a resistor 35.

The connection B is connected via a blocking diode 51 to the second electronic switch circuit 20, which consists of the resistors 21, 23, 42, a capacitor 19, a diode 25 and a silicone-controlled rectifier (3CI1) 22. Of the second electronic switch circuit is not available the mechanical switch 10 in connection, also with the first electronic switch circuit 30 and the solenoid 5. The cathode 24 of the SCR 22 is connected to one end of the solenoid coil through a diode 25 and is through a resistor 23 (preferably 1C ohm) to the other end of the solenoid 5 connected. The control electrode 26 of the silicone controlled rectifier 22 is also connected to the other end of the solenoid coil 5 connected via an resistor 21, the resistance of which is at least ten times greater than the resistance of the Resistance 23 is. The capacitance 19 is connected to the connection B of the mechanical switch 10 via the diode 41 is arranged so that it blocks the current or prevents it, after a discharge of the capacitance 19 back to the mechanical Switch 10 to fHessen. Resistor 42 represents one The current limiting resistor is dimensioned such that it controls the time it takes for the capacitance 19 to discharge to ground potential 49 via SCR 22 is required. Preferably, the resistance of resistor 42 is at least approx. 100 times as large as the resistance value of the resistor

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"αϊ the connection C is connected to the ignition circuit, however is not inclined.

With reference to Figure 3, the mode of operation of the start-prevention control circuit should now be ' described v / earth.

The mechanical switch is initially in the

strop is fed to ports B and C.

The i'berganrsstror. ^1st charges the capacity 19 to the voltage potential of the battery 1, while through the resistor 42, the diodes 31, 33, and the base - "" he transition of the transistor 32 to cash 49, a continuous current is built up. This creates a voltage of approx. 2.0 V from connection point 47 to! Cup 4 ^.

The SC:! 22 is off. Zs no current flows through the SCR 22, as the voltage across the SCR 22 (anode 28 for Piatode 24) is smaller than the Yorwärts breakdown voltage required for switching on the SC'A. The voltage at connection point 47 according to Ilasse is almost 2.0 V. As a result, no strain flows through the SCR 22, the resistors 21, 23, the diode 25 and the solenoid 5 to the cash register 49.

The transistor switch 32 is switched on and the transistor switch 34 is switched off because there is no voltage from the battery at terminal D. No current flows through Cs the emitter-collector circuit of the transistor 32, the resistor 35, the transistor 34 and the solenoid 5.

SAD ORIGINAL

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The mechanical switch is switched to the "start" position. Current is fed to terminals B, C and D.

The SCR 22 remains in the OFF position as the required Forward breakdown voltage to turn on the SCR not available is.

The transistor switch 32 is switched on and the transistor switch 34 is switched on. The voltage supplied to the connection D tensions the emitter-base junction of the transistor 34 forward forward, thereby allowing transistor 34 to operate in its normal switching operation. Since transistor 32 is switched on, a current (1-u) flows in the base circuit of the Transistor switch 34. This turns on the transistor switch 34 ″ and current can flow through the solenoid coil 5, so that the starter motor 3 is excited and can attack. The diode 25 prevents the collector current of the Transistor 34 can flow through resistor 23 to ground 49.

The mechanical switch was turned back to the "ON" position brought

The voltage is removed from terminal D.

The SCR 22 is switched on. The transition voltage generated by the collapsing electromagnetic field of the coil 5 if the current is interrupted abruptly, a transient current results, which is passed through the resistor 23, the diode and the coil 5 flows. This transient current causes the cathode 24 of the SCR 22 is more negative than the control electrode 26, so that a control pulse is generated which the SCR 22 switches on. (When the anode-to-cathode voltage is lower than the breakdown voltage, the SCR 22 can by a

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small impulses are switched on, typically 1.5 V and 30 milliamps, which is applied from the control electrode 26 to the cathode 24). When the SCR 22 is switched on, it remains conductive, until the anode current is interrupted or diverted or diverted by an external device for approx. 20 microseconds will.

The transistor switch 32 is turned off and the transistor switch 34 is also switched off. Since the SCR 22 is switched on, the voltage drop from the connection point is 47 to ground = 1.0 V, which however is insufficient to forward bias the diodes 31, 33 and the transistor switch 32 to be switched on. When the transistor switch 32 is switched off, no current can flow through the emitter-base junction of the transistor switch 34 flow. Accordingly, the transistor switch 34 is turned off when the transistor switch 32 is turned off is.

The mechanical switch will return to the "start" position brought

The transistor switch 32 and the transistor switch 34 remain off.

The SCR 22 remains switched on. If the switching sequence of the mechanical Switch 10 = "ON" - »START« - »ON» is, so has a Returning the mechanical switch to the start position does not result in any excitation of the solenoid 5. This results from that the transistor switch 34 is in the off state is held due to the conduction of the SCR 22, which keeps the transistor 32 off, so that no emitter base current can flow through transistor switch 34 and turn transistor 34 on.

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- ίο -

The mechanical switch is brought to the "OFF" position

The power supply voltage is removed from terminals B, C and D.

The SCR 22 remains on until the discharge current from the Capacitance 19 which flows through resistor 42 and SCR 22 until it has dropped almost to zero, whereupon the SCIl 22 is switched off will. Accordingly, the capacitance 19 and the resistance 42 represent the dominant elements that determine how long the manually operated switch is in the "OFF" position must stay before the SCR. automatically closes bzxv. turns off and the solenoid can be re-energized. Should the mechanical switch 10 switch to the "EIIT" before the SCR is switched off or "START" position, then the 3Ck remains switched on and prevents the solenoid 5 from being energized. Preferably, the time during which the switch is in the "OFF" position must remain equal to or greater than the Time required to stop the starter motor and / or gearbox or to stop the movement that originates from a previous attempt to start the machine » Now the mechanical switch for a correct period of time

W was held in the "OFF" position, then the starter can. lenoid must be re-energized and the engine started.

All details which can be recognized in the description and shown in the drawings are important for the invention.

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Claims (3)

2U2938 r> atentans Γ1 J "electrical starting system for internal combustion engines, with an Itror supply source, an electric starter motor, an "electromechanical" device for mechanical coupling of the electric starter motor with the internal combustion engine and initially electrically connecting the power supply source to the electric starter motor to start the combustion engine, v / whether the electromechanical device includes a solenoid and a mechanical switch connected to the power source, the mechanical switch being a Contains a large number of switch positions with a START position, . characterized in that the electrical "tartsyster: Has the following facilities and characteristics: Dine first electronic switch circuit (30) for controlling the flow of current between mechanical switch (10) and solenoid (5), wherein the first electronic switch circuit (30) can assume an "EIK" state in which a sufficient amount of current from the power supply source (1) to the solenoid (5) to the Can excite the same flow if the mechanical switch (10) was initially set to the "START" position, and can assume an "OFF" state in which energization of the solenoid (5) is prevented; a second electronic Switch circuit (20) for controlling the state of the first electronic switch circuit (30), the second electronic Switch circuit (20) is designed on the one hand in a suitable manner so that it is the first electronic switch circuit (30) as a function of a voltage induced due to the collapsing electromagnetic field of the solenoid (5) can bring into the "OFF" state when the electrical power supply is removed from the solenoid (5) uid at Move the mechanical switch (10) out of the START position 209812/1000 and on the other hand is designed in such a way that it is the first brings electronic switch circuit (30) into the "ON" state, depending on the switching of the mechanical Switch (10) to a selected position corresponding to a certain period of time that must elapse before the mechanical Switch (10) is brought back to the START position, whereby the electric starter motor (3) cannot be excited, until the mechanical switch (10) has been moved to a selected position for a certain period of time. 2. Starting system according to claim 1, characterized in that the first electronic switch circuit (30) for controlling the Current flow to the solenoid (5) consists of a transistorized switch (32, 34), and that the second electronic Switch circuit (20) for controlling the state of the first electronic switch circuit (32, 34) from a silicone-controlled There is a rectifier (22), the cathode of which is connected to the solenoid (5) in terms of circuitry. 3. Starting system according to claim 2, characterized in that with the anode (28) of the silicone-controlled rectifier (22) the mechanical switch (10) with a resistor "stands-capacity network (42, 19). 209812/1000 Blank page