DE19922332C1 - Automobile safety device for disconnection of battery uses 4-stage starter switch with jump starting point and battery terminal, onboard network terminal and load terminal for load components within crash damage area of vehicle - Google Patents

Abstract

The safety device uses a 4-stage starter switch (16) incorporating a jump starting point (15) and contact points for a battery terminal, an onboard network terminal and a terminal for electrical load components, e.g. the starter motor (12), the electrical generator (13) and an electric fan (12a), positioned in the part of the vehicle which is likely to be damaged in an accident. An overcurrent within one of the latter components is detected by a sensor (19a) for altering the configuration of the switch, for disconnecting the load components while maintaining the battery supply to the onboard network.

Description

The invention relates to a safety device for Vehicles according to the preamble of claim 1.

In modern motor vehicles, the number of electr tric control units corresponding to the number of to an on-board network of hanging consumers, so that to increase operational safety, the control units usually with an in-vehicle bus system are networked and in a kind of ring line from one central control device digital switching signals received by means of microprocessors in the Steuerge advise decrypted and in appropriate commands to the immediately adjacent recipients are implemented.

Orient such data bus systems in motor vehicles usually the so-called CAN standard (Controller Area Network). As a rule, therefore Control devices or those arranged in them  Microprocessors after switching off the vehicle one depending on the type of control unit Delay time into a sleep or sleep mode. In this state, the quiescent current consumption is the Control units relatively small, but in total can but permanently on a vehicle battery load current of some 100 mA, ins especially if you have an armed one Monitoring system is added.

Is such a vehicle then standing for a long time without the battery through the generator with the engine running can be loaded, for example with a longer one Absence of the vehicle owner when wintering the Vehicle or for a longer transport on ships overseas, then it comes in contact with the always resulting, unavoidable self-discharge the battery to such a high discharge that under Even the vehicle battery may be incurable is damaged, at least a startability of the Vehicle no longer exists.

A vehicle with such a drained battery will often restarted by an external start, so started by adding a second battery in usually comes from a third-party vehicle, parallel to the discharged vehicle battery is switched. Not rarely, however, especially at night, to confuse the poles, causing not only the already severely weakened vehicle battery, but also  the electrical equipment and control units in the Vehicle, including the entire vehicle electrical system Lich generator and generator diodes as well as the electronics sustained damage.

However, with a very deeply discharged own Vehicle battery attempt to jump start also failed because the on-board electrical system voltage due to the high current the starter needed during the start, under one Limit can drop, for example 5 volts, so that the control units important for the start are no longer included be supplied with sufficient voltage. This is due to the fact that the extremely deeply discharged Own battery initially practically like a short circuit the vehicle electrical system voltage acts and in this case also sufficient capacity of the external battery Line resistances together with the anyway not avoidable voltage drop on the external battery cause an excessive voltage drop in the vehicle electrical system can.

After all, it can happen occasionally in vehicle accidents in addition, electrical lines in particular in the engine compartment area, causing a Arcing or an arc in the event of a short circuit can lead, so that with the not uncommon Leakage of fuel poses a significant fire hazard consists.

The problem with motor vehicle electrical systems is therefore the  Protection by immediately disconnecting the battery in the Damage event, also the protection of the electrical system and its components against reverse polarity, the protection of the turned built vehicle battery from deep discharge like them for example for overseas transport, for longer periods The vehicle comes to a standstill if the load is too high associated discharge can occur and finally the protection of the vehicle electrical system against overvoltage, as with a jump start, also as a so-called called jump start, can occur.

It is known to protect the battery against Tiefent to currently guarantee cargo for overseas transport afford that the battery using a circuit breaker after loading the vehicle on the ship manually from Vehicle electrical system is disconnected. When unloading, that is To be able to drive the vehicle from the boat Disconnector closed again and before the final one Finally commissioning at the respective dealer away.

The problem mentioned is particularly serious Wrong polarity in the case of jump-start assistance, since it is eliminated of damage only by replacing the insufficient protected, irreparably destroyed by incorrect polarity Electrical and electronic components at accordingly high cost is possible. Has a special meaning Reverse polarity protection, for example with the H-bridge connection control of servomotors using power MOS Transistors, because in the event of polarity reversal, the current through the Inverse diodes are not limited by the load.  

Furthermore, the deep discharge of batteries leads to sustainable damage because in normal operation the generated by the electrical charge on the electrodes electrical voltage this against the aggressiveness of the Protects sulfuric acid. Breaks this tension due to deep discharge together, the protection of the Electrodes, and there are signs of decomposition, after a short time the electrodes are irreversible severely damage that due to the drastic destruction the storage capacity the storage function of the battery get lost.

The following publications relate to battery disconnectors or to the possibility of disconnecting a battery from its consumers under certain circumstances if there is a risk of deep discharge or other damage:
DE 34 02 372 A1, DE 42 11 578 C1, DE 33 03 185 A1, DE-AS 10 86 322.

In DE 34 02 372 A1 are two conductive, each other coaxially opposed electrodes by a between isolator piece lying them separately, but in the Normally from an electrically conductive jumper is bridged. The switching bridge can be by a Open the axial displacement of a sleeve.

DE 42 11 578 C1 describes a battery disconnection  Direction for motor vehicles with a battery disconnect switch that comes from the battery compartment manually and from Driver's seat off with a safety main switch can be operated remotely. Before a possible Opening the battery isolating switch must all first ignition-switched consumer switched off and one Engine shutdown can be initiated.

Another battery known from DE 33 03 185 A1 disconnector has a handle on the one hand arbitrary manual switching on and off using in a sleeve arranged cam tracks, on the other can also be actuated in the switch-off direction another source of power, for example one Trigger an explosive cartridge that is triggered by a pulse Trigger depending on the response of a fire detector is cash.

Reverse polarity protection devices, such as battery chargers or when connecting batteries to electrical systems from Motor vehicles are from DE 42 31 970 C2 and DE 196 03 117 A1 known.

The known reverse polarity protection arrangements for a Battery charging system and / or an electrical system for Motor vehicles are usually based on the fact that a Sensor circuit is provided, the polarity of the battery to be detected and connected to a charger or to the vehicle electrical system only for example by closing a switch  allows if the polarity is correct.

The one intended for a battery charger Reverse polarity protection device of DE 42 31 970 C2 works so that of a reverse polarity-detecting microprocessor the connection point for the positive pole of the load Battery via a voltage divider itself a positive one Voltage is supplied in the event that the microprocessor a proper one at a first detection entrance Polarity cannot be detected with certainty. It actually results wrong polarity via this voltage divider then one so strongly towards negative values shifted measuring voltage to be evaluated by the microprocessor on the voltage divider that a for polarity reversal correct polarity reversal message and corresponding Measures taken, for example polarity reversal of the An conclusions can be made.

In the reverse polarity protection circuit according to DE 196 03 117 A1 MOSFET transistors are provided, through which the voltage drop caused by the protective circuit is significantly reduced, so that the use of Protection circuit even at low DC voltages is possible.

Furthermore, from DE-AS 10 86 322 is an electrical High-voltage switch known in which an axial Movable pin-shaped switch contact and two with this provided cooperative fixed contacts are. Both the switch contact and the fixed one  Contacts are arranged in a control room, which by is surrounded by a double-walled jacket. This is ensured that due to the metallic Condition of the outer wall of the control room in any case, parts with a high field strength outside the Switch room. Relationships with one with Low voltage battery disconnect switches are unavailable.

It is also known for a discharge protection circuit for electricity storage in a motor vehicle (DE 40 40 405 A1) to provide a latch circuit that takes effect when parking the vehicle and then switched on consumers due to the actuation an electrical isolating device from Electrically stores electricity storage safely.

It is also a facility for protection of a main current path in a means of transport (DE 41 10 240 C1), an electronically controllable, Switch-off device for the battery controlled establishment of a separation between Arrange main current path and battery as soon as one Current characterizing short circuit situation detected becomes. The switch-off means can be, for example electromagnetic actuator or one Detonator.

The invention has for its object a safe to create a facility that is able to  by means of a single switching element Encounter problems and in addition to a deep discharge Protection against polarity and reverse polarity to ensure that in an accident-prone area of the vehicle Consumers can be switched separately from the rest of the electrical system are.

This task is solved by the security mentioned at the beginning direction for vehicles according to the invention by the Features of claim 1 and enables by only a variety of possible circuit variants comprehensive motor-driven switch in the area Vehicle electrical system / battery / external starting point of a motor vehicle an inexpensive protection against possible Problem cases of the kind described at the same time drastically increased security.

The safety device ensures both Disconnect the battery from the electrical system in the event of a Transport or a long shutdown of the vehicle, preferably automatic, and also ensures that Reverse polarity in the case of a third-party battery connection is reliably prevented.

For the increased security offered at the same time general operation of the motor vehicle, namely separate switchability from starter / generator area as well as other areas in the risk of crash area Consumer, such as an electrically driven fan only a slight change in the wiring structure  of the vehicle required.

The one in the area of the safety device che starting point is designed so that it too used for the external start of a foreign vehicle in addition to the correct connection a third-party battery, for example via a jump starter cable to the vehicle when the battery is severely discharged through jump start to start up again.

The motor moves into different contact positions bare high-current disconnector is therefore able at least four connecting segments, namely battery, Jump start base, starter / generator as crash sensitive area and electrical system in the different configurations together switch.

It is advantageous that these switching operations partly also automatically via suitable sensor means upon detection of certain switching interventions required operating states can be realized Make use of relays unnecessary for those here currents occurring in extreme cases of under certain circumstances several hundred amperes are unsuitable.

For the production of the contact connections of the individual segments, including multiple segments can be connected to each other as required  is one on a tubular contact carrier slidable switching sleeve provided, in so far a Contact bridge function fulfilled and in any way is motor-driven. Use is preferred an electric motor, preferably a stepper motor, which a reduction gear, for example tooth rack GE / pinion, the shift sleeve in a desired Axial position moves in each case.

Finally, there is also a manual adjustment of the Contact bridge / switching sleeve by means of an actuation handles possible, if desired, for example at a deeply discharged and accordingly weak battery and motor switch in the disconnected position Switch to a contact position between the the intended jump start base and the Vehicle electrical system / starter is no longer possible.

Alternatively, it is also within the scope of the invention appropriate frame, one for the switching movements of the Motor switch responsible switching logic or other Control unit with a supply line in any case also with the jump start base to connect constantly, complementing one anyway existing polarity sensor from the switching logic to Jump start base.

Further advantages and features of the invention are described in Connection with the drawing explained or are as refinements and developments subject of  Characteristics of the subclaims.

The drawing shows in

Fig. 1 schematically shows an overall view of the vehicle structure with consumer and battery, in the front of the vehicle crash-sensitive aggregates and laterally in an enlarged view of the battery downstream safety device with motor switch that

FIGS. 2a, 2b, 2c and 2d are cross-sections of the tubular contact support as part of the motor switch, corresponding to the lines IIa-IIa, IIb-IIb, IIc-IIc and IId IId of FIG. 3 and

Fig. 3 together with the schematic representation of the mechanical structure of the motor switch possible switching configurations that can be taken up by the switching sleeve designed as a connecting contact bridge on the contact carrier.

Fig. 1 shows a highly schematic in an oval circumnavigation of the structure of a motor vehicle with general electrical consumers leading electrical system connection 14 , battery 10 , safety device 11 with external start base 15 and from this further connecting lines 20 to the battery 10 and 19 , which leads to such consumers , which are in the possible crash area of the vehicle, namely generator 13 , starter 12 and, if present, electrically driven fan 12 a.

On the right side of Fig. 1, the Sicherheitsein device 11 is shown enlarged enlarged; it includes a motor switch 16 , which is designed as a high-current disconnector and whose schematic structure is shown in Fig. 3, with an associated motor drive 16 a, a switching logic 17 and this associated sensor system 18 , which have a plurality of sensors with associated sensor lines 18 a , 18 b, 18 c different areas of the motor vehicle essential for the operation of the engine switch are detected and implemented in the motor-controlled switching operations of the engine switch.

The switching logic 17 is further associated with an input circuit 17a that may be placed accessible at any point, for example in the engine compartment, but optionally also, for example, protected by a cover in the passenger compartment and the driver and via which the driver's the motor drive 16 a of the motor switch 16 acting switching logic 17 can issue corresponding switching commands. The switching logic will then execute these switching commands if they prove to be permissible at the time from the respective operating conditions and other switching parameters of the vehicle and its electrics.

This is discussed below in connection with the Explanation of the function of the safety device still received.

FIG. 3 shows the schematic structure of a preferred exemplary embodiment of a motor switch 16 in the form of a high-current disconnector. In order to ensure the various switching positions that are required to implement the desired function, the structure of the motor switch of FIG. 3 comprises a tubular contact carrier 21 with four mutually insulated contact areas or segments 21 a, 21 b, 21 c and 21 d. The segments 21 a, 21 b, 21 c and 21 d are formed as partial regions of the tubular shape and are separated from one another, for example, by a suitable insulating layer 22 , so that the entire contact carrier 21 has the tubular shape shown in FIG. 3. The segment 21 a is, as shown in FIG. 1, connected to the vehicle battery 10 via the line 20 ; the segment 21b is in communication with the foreign start terminal 15; The segment 21 c is connected via the line 19 to the starter 12 , the generator 13 and other electrical units located in the crash area and therefore primarily at risk. The vehicle electrical system is connected to segment 21 d via connection 14 , which represents all other electrical consumers of the motor vehicle.

Since the switching element provided in the isolating switch shown in FIG. 3 has the form of a switching sleeve 23 which is axially displaceable on the tubular contact carrier 21 and which is designed as a contact bridge which connects the individual contact segments to one another or, depending on their switching position, also separates, the individual insulated extend Segments 21 a, 21 b, 21 c and 21 d segment-like at least partially also in the axial direction and overlap, so that a shift of the switching sleeve 23 , as it is called in the following, determines the desired switching positions.

The axial extent of the switching sleeve 23 is dimensioned such that all possible switching connections are realized by its axial displacement, so that, in the desired case, the axial length of the switching sleeve 23 can correspond to the total length of the individual segments, so that, for the maximum case, all the segments present on the tubular contact carrier with one another connect and be able to contact each other.

Depending on the side from which the switching sleeve starts is moved over the contact carrier, result then the individual explained below Switch positions. Due to the mechanical structure of a such high-current disconnector, in which a tubular contact carrier from one also tubular, with an inner bore Contact bridge is telescopically overlapped and encompassed, reliable contact connections also result for high and highest currents, whereby, if desired, the  Switching sleeve can also be formed longitudinally slotted and through their own elasticity or through spring force acting from outside also on the in their shape corresponding to their own inner bore Contact surfaces of the contact carrier is pressed.

The standard configuration is determined by position A in accordance with FIG. 3, in which the electrical connection between the components battery + vehicle electrical system + starter / generator (as lying in the area at risk of a crash) is obtained via the correspondingly shifted switching sleeve 23 .

Respective switching configurations are indicated in the form of thick solid lines below the switch structure in FIG. 3 and, in terms of their length and position, indicate the position of the switching sleeve 23 , which is shifted into this contact position by the switching logic 17 by means of the motor drive.

The standard configuration corresponding to position A of FIG. 3 ensures that all functions are available in the vehicle, that is to say corresponds to the normal operation of the vehicle, the external starting point remaining free of voltage.

The external start configuration corresponds to position B in FIG. 3 and also includes the switching position customary in production, overseas transportation for longer periods of standstill and in workshops, in which the vehicle battery is disconnected from the remaining electrical components of the vehicle. The jump-start configuration also ensures that for longer periods in which the battery is not being charged, the quiescent currents of the control units cannot discharge it deeply. In workshops or even in production, it is common and helpful to separate the battery from the consumers in order to be able to work freely and to avoid damage. This is now possible with a corresponding saving of time without having to loosen pole terminals.

The jump-start configuration therefore corresponds to the switching Connection of vehicle electrical system + starter / generator + jump start base, the vehicle battery being connectionless remains.

The jump-start configuration also ensures represents that the disconnected own vehicle battery, in In the event of a deep discharge or in the event of aging does not have enough capacity anymore Jump start the jump starting battery not additionally charged. The on-board electrical system is used by the external starting battery supplied. Is the Internal combustion engine then started, the vehicle's own generator supply the vehicle electrical system, and the Vehicle battery is also switched on again. H. the Disconnector is then returned to position A transferred.  

It goes without saying that the previously explained and the following configurations can either be started automatically via the switching logic or, on the basis of a corresponding command given by a driver or an operator, using corresponding pushbuttons 17 'or a keyboard 17 ''.

An automatic reaction is useful, for example, if the switching logic 17 detects a beginning deep discharge of the vehicle battery, for example after a long standstill in winter, via the sensor system 18 , but a disconnection of the battery has been overlooked. In order to avoid the impending deep discharge, the switching logic 17 moves the motor switch 16 to position B. It is understood that by querying the operating system beforehand it is ensured that this separation is also possible, that is to say the internal combustion engine is not running or is just starting or there is an operating state of the vehicle that prevents the battery from being disconnected.

For this purpose, the sensor system 18 has suitable sensors to be used, the representation of which has been omitted in FIG. 1 for reasons of clarity, and the switching logic 17 is programmed accordingly in order to only then automatically or also on the basis of external ones in these and in the other configuration cases Commands to initiate appropriate switches of the engine switch 16 if this is possible due to the vehicle operating conditions.

Another particularly noteworthy configuration in the possible switching positions of the safety device is the crash configuration corresponding to position C of FIG. 3 with the battery + vehicle electrical system switching connection.

This means that the battery is only selected components of the vehicle electrical system remain connected, who are not in a crash-prone area of the Vehicle are arranged.

The battery is disconnected from the starter / generator and other electrical components in the crash area of the vehicle during or before an accident due to a (pre-) crash signal. This prevents an arc from occurring due to an accident-related short circuit in the area of these components or their electrical leads, which can result in dangerous consequences for the vehicle. A separation of these components can also be carried out before an accident, because due to the cabling structure according to FIG. 1, no electrical consumers relevant for the short-term operation of the vehicle are supplied via this cable 19 , which leads to the components at risk of crash. In addition, the sensor system 18 also has a sensor 19 a reacting to an overcurrent in the cable 19 , so that in the relevant case the motor switch opens this connection by releasing the contact connection to the cable 19 (corresponding to segment 21 c of the contact carrier).

An equally interesting switch position results as a third-party vehicle start configuration corresponding to position B1 of FIG. 3 with the switch connections battery + vehicle electrical system + starter + third-party starting point. This makes it possible for a third-party vehicle to give start assistance based on the third-party starting point present in the own vehicle, since the self-contained battery is connected to the third-party starting point. This is also of considerable advantage, since it is not necessary to laboriously expose your own battery terminal clamps in such a not uncommon case, but you can easily use your own jump starting point, which is easily accessible and energized by the appropriate motor switch position. It is evident, moreover, that the position B1 is the configuration in which the largest number occurring of contact junctions, which means that the switching sleeve 23 should have in the maximum case, therefore, also a contact carrier 21 adapted axial length to all of the listed shift positions ensure to can, taking into account axial overlaps of the contact segments.

Then there are two more optional configurations appropriate according to positions B2 and B3 and possible, in position B2 also the vehicle electrical system from Jump start base is still separated, which for some  Workshop work makes sense, but is equally like position B for longer overseas transport or Standstill is suitable while in position B3 at all no contact connections between the individual driving there are also suitable components Position for workshop, overseas transportation or longer Standstill of the vehicle. This position is below Circumstances also of particular importance, if all vehicle components in the event of an accident are to be disconnected from the power supply overall.

The axial segment overlaps that can be seen in the cross sections of FIGS . 2a and 2d enable certain switching connections to be made even with a shorter axial extension of the switching sleeve 23 .

Claims (8)

1. Safety device for vehicles, in particular high-current disconnect switch for battery and vehicle electrical system of a motor vehicle, characterized by an at least four-stage switch (engine switch 16 ) comprising an external starting point ( 15 ), the further contact points of which have a battery connection ( 21 a), an electrical system connection ( 21 d) as well as a separate connection ( 21 c) from the other consumers connected to the vehicle electrical system for the electrical components (starter 12 , generator 13 , electrical fan 12 a) located in an area at risk of an accident. 2. Safety device according to claim 1, characterized in that each with battery ( 10 ), vehicle electrical system ( 14 ), jump start ( 15 ) and accident-prone electrical components verbun which four contact points form segments on a tubular contact point carrier ( 21 ), with the selective connection the contact points a switching sleeve ( 23 ) fulfilling a contact bridge function is arranged axially displaceably on the contact carrier ( 21 ). 3. Safety device according to claim 1 or 2, characterized in that a via a sensor ( 18 ) sensing vehicle operating parameters and including in their switching commands switching logic ( 17 ) a motor drive ( 16 a) for the contact carrier ( 21 ) and switching sleeve ( 23 ) controls existing motor switch ( 16 ). 4. Safety device according to one of claims 1 to 3, characterized in that the sensor system ( 18 ) with a current sensor ( 19 a) reacts to overcurrent conditions in an accident-prone area of the vehicle electrical consumers (starter 12 , electrically driven fan 12 a) and transfers the engine switch into a configuration that only connects the battery ( 10 ) to the rest of the vehicle electrical system when the component area that is at risk of being switched off is de-energized. 5. Safety device according to one of claims 1 to 4, characterized in that the switching sleeve ( 23 ) in one

• - First standard configuration (position A) battery, vehicle electrical system and components located in the vehicle area at risk of accidents (starter 12 , generator 13 , electrically driven fan 12 a),
• - second jump-start configuration (position B) on-board electrical system, electrical components (starter / generator) and accident-prone starting point,
• - a third accident configuration (position C) battery with the remaining components of the vehicle electrical system, eliminating electrical components in the area at risk of an accident,
• - in a further configuration (position B1) battery, vehicle electrical system, starter / generator area and third-party starting point to enable the auxiliary start of a foreign vehicle,
• - In a further configuration (position B2) for a stay in the workshop, overseas transport and a long standstill, only the jump start base and the starter / generator area alternatively connect and finally in one
• - Last configuration (position B3) can be positioned outside the contact point area of the contact carrier ( 21 ).

6. Safety device according to one of claims 1 to 5, characterized in that for shifting the switching sleeve ( 23 ) in the different, selected contact points of the contact carrier ( 21 ) each interconnecting positions an elec tromotor, hydraulic and / or electromagnetic drive ( 16 a) is provided, which is controlled by the switching logic ( 17 ). 7. Safety device according to one of claims 1 to 6, characterized in that the switching logic ( 17 ) has a manually operated input circuit ( 17 a). 8. Safety device according to one of claims 1 to 7, characterized in that an actuating element for manual-mechanical adjustment is arranged on the switching sleeve ( 23 ).