DE1928365C3 - Device for switching on and automatically switching off the electric starter of internal combustion engines - Google Patents

Description

a) that devices are provided which close the second switch (62) before the Starter motor (1) moves the crankshaft again, and

b) that these facilities are automatically in operation occur when the first switch (53) is actuated (Figs. 3 and 4).

2. Apparatus according to claim 1, characterized in that the devices which close the second switch (b 2) then come into action when the first switch (53) returns to its open position (F i g. 3 and 4) .

3. Apparatus according to claim 1 or 2, characterized in that the first switch (53) a manual pressure switch is with contacts (52) in the starter circuit and contacts (54) in the control circuit to close the second switch (b2).

4. Device according to the preamble and identifier "a)" of claim 1, characterized in that that a third switch (28) is provided, the actuation of which generates a pulse through a bistable flip-flop (25,29) returns to its starting position in which it the second switch (7) keeps closed, while the toggle switch occurs when the former occurs Control pulse controls the second switch (7) in its open position (Fig. 2).

5. Device according to claims 1 to 4, characterized in that the electrical Control pulse to open the second switch (7) due to a pressure increase in the fuel injection system is triggered.

6. Device according to claims 1 to 4, characterized in that the electrical Control pulse to open the second switch (7) by the compression pressure of the affected Machine cylinder is triggered.

7. Device according to claims 4 to 6, characterized in that the on the. Spark plug cable (19) of the cylinder involved High voltage of the primary winding (20) of a step-down transformer

(21) is supplied, its secondary winding

(22) is connected to the input of the bistable trigger circuit (25, 29) via a diode (23).

8. Apparatus according to claim 3, 5 or 6, characterized in that the contacts (52) in Row with the switch (ft 2) operated by a main relay (B), its excitation winding on the one hand via a normally open contact (54) of the switch (53) bridged by a normally open contact (ftl) and on the other hand via a break contact (al) of an auxiliary relay (. <4} to a direct current source (4) connected.

9. Apparatus according to claim 8, characterized in that the excitation winding of the main relay [B) is connected via a forward-biased diode (62) with an interrupter contact (47) and the excitation winding of the auxiliary relay (^ 4) between the direct current source (4) and the interrupter contact (47) is switched.

10. Device according to claims 1 to 6 and 8, characterized in that the excitation winding of a main relay (B) is connected via a resistor (64) and a diode (68) to the collector of a transistor (66), the emitter of which is connected a direct current source (4) is applied and the base of which is connected to an interrupter contact (47) via an adjustable resistor (69) and to the emitter via a capacitor (70).

The present invention relates to a device for switching on and automatically switching off again the electric starter of internal combustion engines for brief rotation of the crankshaft and performing maintenance work when the piston is in the position near or at top dead center, wherein the starter motor switch is bridged by two switches in series, the first of which Switch is set up for the random activation of the starter motor, during which normally closed second switch opens and thus interrupts the bridging if one of him Associated switching device receives an electrical pulse that causes the top dead center to be reached of a piston.

The adjustment of the valve clearance in internal combustion engines should take place with the valve completely closed, with the associated tappet being supported against the rear side of the corresponding camshaft cam. This state is given both for the inlet valve and for the outlet valve of an internal combustion engine when the piston of the cylinder in question is either at dead center or at least approximately at dead center after the compression stroke.
When examining the tightness of the cylinders, the valves should also be closed and the pistons of the various cylinders should be brought into the aforementioned dead center position one after the other.
In engines with a starter crank, the crank

• the bel shaft can be rotated with this in order to guide the pistons into the correct position one after the other. this is then expediently done after unscrewing the spark plugs to avoid unwanted induction voltages to avoid. Since nowadays only a small number of motors can be rotated by means of a starter crank generally by engaging a gear and then sliding back and forth of the vehicle the crankshaft and thus the

Cylinder piston rotated. It is obvious that it is difficult to use the high voltage in the spark plug in this way to use the correct piston circle of the cylinder involved as a control signal, setting to achieve. In motor vehicles with FIG. 3 the scheme of a first embodiment,

an automatic instead of a manual gearshift in which the control signal is taken from the primary ignition coil, this possibility of rotating the crankshaft 5 circle, and

not given. 4 shows the scheme of a second embodiment

A device is known which shape the piston, in which the control signal is also taken from the primary internal combustion engine in the area of the upper ignition coil circuit. Goal point by a number of short-term ar- F i g. 1 shows a starter 1, the starter relay 2

laßimpulsen brings _xo via a normal connection provided in the vehicle

This device is used to examine the circuit breaker 3 with one pole of a battery 4 electrical interrupter system, in particular the one which is connected, the other pole of which is connected to ground. Functionality of a parallel to the interruption The device according to the invention has an intermediate contacts lying capacitor in the distributor. see points 5 and 6 to be connected, i.e. the The breaker contacts must start 15 starter switch 3 bridging circuit on, the two This examination must be open, which thereby includes switches 7 and 8 connected in series. the is enough that the first switching means intermittently loaded switch 7 is controlled by a relay 9, the be actuated by means of second switching means a switch 8 is a manually operated switch. The re-energy source with an arrangement for rotating the lais 9 is controlled by a switching device 10. To connect the machine, the second switching ao in such a way that the relay 9 is normally open or closed when the switch 7 is closed when the unmistakably closed. However, if the intruder contacts are open or closed. input 11 of the switching device 10 a control signal - in this device two are arranged in series, the switching device 10 lets the switch between a power source and the relay 9 drop, whereby the switch 7 is opened Starter of the internal combustion engine provided. At »5 the switching device 10 has a bistable toggle of the known device is a reset after switching, which changes its conducting state when a The opening of the breaker contacts is not preceded. Control pulse to input 11 of the switching device. so that after opening another turn 10 is placed, and by placing a «, the piston is no longer possible. Reset signal to a point 12 (Fig. 1) in the

In contrast, it is the task of the present 30 original position to be returned. Invention to provide a device that can be The signal applied to point 11 from

fan and quicker way enables one after the other the spark plug circuit of the cylinder involved from the pistons of the various cylinders in a compound - the pressure in the injection line of this internal combustion engine whose valve clearance is set or cylinder responsive member or from an in whose tightness is to be measured, in the 35 of the spark plug opening of the cylinder to bring the desired dead center position, each pressure sensor being supplied. In all of these cases because the device is reset to its original state when the piston is at its top dead center initial situation takes place in order to approach the process for which a control signal is generated: in the first case over repeat next cylinder. the high-voltage im-

According to the invention, this object is achieved by pulsing, in the second case in which the fuel is released, in that devices are provided, which occur in the spray line, from the injection pump second switch close before the starter motor delivered high fuel pressure and the third the crankshaft moves again, and that this one-case when the compression pressure is a certain directions automatically come into action when the value exceeds.

first switch is operated. 45 The mode of operation of the device is as follows:

In a further embodiment of the invention, a switch 7 controlled by the relay 9 is provided and a third switch, the actuation of which is initially closed. Now if the operated by hand A pulse is generated by which a bistable toggle switch 8 is also closed device returns to its original position, in which conductive connection from the battery 4 to the starter. Keeps the second switch closed, while 50 relay 2, whereby the starter and thus also the the flip-flop circuit begins to rotate when the first-mentioned crankshaft occurs. As soon as the Control pulse the second switch in its open approach of the piston to the top dead center position controls. by the appearance of the control signal at the point

With the device according to the invention, the switching device 10 is operated when the 11 is activated The advantage achieved is that in a simple manner several KoI 55 relays 9 and opens the switch 7. This is ben an internal combustion engine one after the other in which the starter 1 is switched off, whereby through the inner The desired dead center position can be brought to fric- tion of the engine and the compressions that occur, the setting of the valve clearance or the test pressure of the piston practically immediately in the upper position fen of the compression pressure, whereby it remains dead center or in its vicinity. so it is always possible to tell which cylinder piston 60 the valves can be adjusted. After that you can is in top dead center. the switching device 10 with the help of a to the

Further design features of the invention, point 12 (FIG. 1) applied signal to the original result from the following description of the borrowed position and the process for the in the drawings shown in the drawings are repeated for the next cylinder, games. It shows 65 F i g. 2 shows the circuit diagram of an embodiment

1 shows a circuit diagram of the single form according to the invention, in which the control signal from the ignition system direction, the internal combustion engine, namely from the

Fig. 2 is a circuit diagram of an embodiment of the affected cylinder high voltage occurring,

5 6

is led. This circuit is blocked via terminals of transistor 25, transistor 29 is conductive, 13,14 connected to the battery of the vehicle. the transistor 37 blocked and the transistor 42 lei-A terminal 15 will be with the starting relay, so with tend, so that the relay 9 picks up again and the point 5 in the circuit according to Fi g. 1, connected switch 7 closes.

the. This creates a connection via the 5 Fig. 3 shows an embodiment in which the Relay switch 7 and the manually operated switch 8 to the control signal of the primary circuit of the ignition coil eninomdem contact of a switch 16. With the help of the switch, via the interrupter. As is known, the starter can be connected to one of the poles of the car. This has a non-battery connected to ground. breaker contact, which is shown in FIG. 3 shown in dashed lines

The normal connection of the ignition coil is established and given the reference number 47. triggers and the ignition coil instead via a connection This contact is supplied after the connection 17 voltage. The ignition coil receives connection to the ignition coil, then current is connected to a terminal 48 via an adjustable resistor 18, while terminals 49 and 50 are connected to the and emits a secondary voltage, the lower battery terminals are connected. A clamp than the normally occurring high voltage is. Pre-15 51 is connected to the starter relay. In the Leizugweise namely during the setting device between the terminals 50 and 51, the spark plug cables are detached from the spark plugs in series, because working contacts 52 of a push button switch 53 and prevent that the engine is accidentally connected to a working contact ft 2 of a main relay B switched, jumps. Since the secondary voltage of the ignition coil The excitation winding of this main relay B is one then can rise very high, to avoid ao on the other hand via normally closed contacts 54 of switch 53 with a sparkover in the ignition coil or in terminal 50 and on the other hand via a normally closed ignition distributor, the ignition coil during this time with al of auxiliary relay A connected to terminal 49, fed with a lower voltage. The contacts 54 are held by a

A primary winding 20 of a 35 is bridged to a spark plug cable 19 of the spark plug of the operating contact ft 1 of the relay B assigned to the cylinder. The auxiliary relay A is closed on the one hand with the line leading to the stepping-down transformer 21 to terminal 50 and on the other hand, the secondary winding 22 of which is connected to the base switch 56 via a changeover contact 55 of a double changeover diode 23 and a resistor 24, the other changeover contact of a transistor 25 is connected. The cathode and 57 with the excitation winding of the relay B and the anode of the diode 23 are connected via capacitors 26 30 normally open contact a 1. The Wechselkon- and 27 on ground. The base of the transistor 25 can clock 55 also leads to the terminal 48 and thus to the breaker contact via a switch 28 to be closed with ground.

get connected. Fixed contacts 58, 59, 60 and 61 are with a

The transistor 25 forms together with a diode 62 connected. The purpose of switch 56 is Transistor 29 and the associated resistors 35 make the device suitable for use in motors (Make collector resistors 30 and 31, resistors 32, where contrary to the usual polarity and 33, a common emitter resistor 34, the positive terminal of the battery is connected to ground Base resistor 35 and a coupling resistor 36) The switch 56 is in the position shown

a bistable multivibrator. If the switch 28 is closed, the device for use in motors is the bistable toggle switch 40, in which the positive pole of the battery is connected to ground in the initial state in which the transistor 25 is. The circuit works as follows: blocked and transistor 29 is conductive. As a result, when the terminals 50 and 49 are connected to the battery, the base of a transistor 37 is closed via a Zener, the relay B pulls via the diode 38 and resistors 39, 40 to the low-position contacts 54 and the closed potential, so that this transistor is blocked and no 45 ^ t a 1 on. As a result, the holding contact b 1 voltage across a collector resistor 41 drops. and the normally open contact ft 2 is closed. When the base of a transistor 42 is thereby pressed in the switch 53, the contacts 52 opposite its emitter are closed at a high voltage, the current is applied to the starting relay, whereby this transistor is fed through diodes 43 and, whereby the starter rotates the motor . 44 and an excitation winding 45 of the relay 9 current 5 ° ^It is now assumed that the interrupter can flow. The relay 9 is energized and keeps the contacts 47 open in this initial position. So switch 7 closed. soon these contacts close, the auxiliary pulls when the rotation of the crankshaft ^rela > ^{s A} - a «f due to the connection of the piston of the cylinder involved approaches the top dead terminal 50 via the exciter winding and the lower point, a chip breaker contact 47 with ground occurs via the ignition system. voltage pulse on the spark plug cable 19. This the contact al is opened, but what voltage pulse passes through the transformer 21 has no influence on the state of the relay B , since the base of the transistor 25, which becomes conductive. As a result, the transistor 29 is blocked via the connection from the terminal 50 via through, the transistor the closed contact ft1, the switch contacts 37 conductive and the transistor 42 blocked. The Re- 6 ° 5? and 58, the diode 62, the switch contacts 60 and the relay 9 drop out, whereby the opening 55 and the undesired induction voltages coming to the ground via the interrupter contacts remains reduced by a diode 46.

that will. The switch 7 and the circuit for the on If the breaker contacts now open,

Let relays are opened. The starter is stopped so both relay A and relay B drop out. quiet. 65 The release time of relay A is chosen so that

The circuit can be used to carry out the after it drops more slowly than the relay B (in the figure most setting work can be prepared by schematically closing a switch 28 connected in parallel to the relay for a short time, whereby the capacitor 63 is shown), so that the Re-

lais II has fallen off. before the normally closed contact a I closes and remains in this state. The contact /> 2 opens and the starter stops because the starter relay is no longer supplied with voltage. As long as the push button 53 remains depressed, the relay B cannot pick up again, since the holding contact / il and, when the switch 53 is depressed, also the contact 54 are open.

However, as soon as the switch 53 is released, the relay ß can attract again: the starter mechanism does not receive any voltage as long as the contacts 52 are open. When the switch 53 of is pressed again, this has the consequence that the process is repeated.

The circuit thus has three stable states; the The transition from one switching state to the other takes place by closing or opening the interruption contacts and unlocking the push button of the switch 53.

The pistons of the various cylinders are therefore brought to or near top dead center one after the other according to the firing order. The position of the rotor of the ignition distributor shows. which is the piston at the top dead center. F i g. 4 shows a modification of the circuit according to FIG. 3. In this case, the auxiliary relay A and the double switch 56 are replaced by a transistor circuit which has two transistors 65.66. namely one pnp and one npn transistor is fitted, whereby the polarity of the battery has no influence on the effect of the ι circuit. In FIG. 4 the elements of the circuit according to FIG. 3 corresponding elements are assigned the same reference numbers.

In this circuit, one terminal of the excitation winding of relay B is connected directly to the interrupter contact 47 on the one hand and to the collector circuits of the pnp transistor 65 and the npn transistor 66 via a resistor 64 on the other hand.

In the corresponding collector circuits _v diodes are 67 and 68. The emitters of both transistors are connected to the terminal 49. and the two bases are connected via a Widcrtand 69 to the connection point of the resistor 64 and · the excitation winding of the relay 0th A capacitor 70 is connected between the base and the emitter of the transistors 65 and 66.

When the breaker contacts 47 are open and the switch 53 is not pressed in, the relay B is energized when the switching device is connected to the battery, since one of the transistors is always one of the transistors depending on the polarity of the battery through the appropriate selection of the resistance of the field winding of the relay B and the resistors 64 and 69 65 or 66 is conductive. The Re-Lo lais B is then excited via the closed contacts 54 and the respective conductive transistor. In the process, the working contacts M and b 2 are closed, but no voltage is yet fed to the starter circuit, since the contacts 52 are open. iS When the switch 53 is pressed in, the contacts 52. close and the relay B remains energized via the holding contact b 1. The starter relay is then supplied with voltage via the closed contacts 52 and b 2, whereby the starter rotates the motor, ao When the breaker contacts 47 close, a connection point 71 of the resistor 64 and the excitation winding of the relay B is connected to ground via the Uhterbrecherkontaktc 47. As a result, there is no longer any voltage on the transistor circuit, and the capacitor 70 discharges through the resistor 69. The relay B , however, remains energized via the closed interrupter contacts 47, and the starter continues to turn the engine.

If the breaker contacts then open again as soon as one of the pistons has reached top dead center. the relay B drops out, because it takes some time until one of the previously non-conductive transistors 65 or 66 becomes conductive again, since the capacitor 70 prevents sufficient base-emitter voltage from being present again immediately. Once the relay has dropped out, it can no longer pick up as long as the switch 53 remains depressed because the contacts 54 are open. Contact bl is also open.

If now the pressure switch 53 is released, the relay B is energized again. However, no voltage is applied to the starting relay because the contacts 52 are open.

The mode of operation of this circuit therefore corresponds to that according to FIG. 3.

1 sheet of drawings

409609/349

Claims (1)

Patent claims: 1. Device for switching on and automatically switching off the electric starter of internal combustion engines for brief rotation of the crankshaft and implementation of Maintenance work when the piston is near or at top dead center, with the switch of the starter motor is bridged by two switches in series, of which the first switch is set up for the arbitrary addition of the starter motor. during the normally closed second switch opens and thus interrupts the bridging, if a switching device belonging to it receives an electrical impulse which (e.g. by opening of the interrupter triggered) indicates that a piston has reached the top dead center, characterized,