DE3820319A1 - Motor vehicle with an accelerator pedal for an engine and a brake pedal - Google Patents

Abstract

In order to safeguard against dangerous acceleration sequences in the event of the accelerator pedal (13) being mistaken for the brake pedal (14), a control device (15) is assigned to the accelerator pedal (13), which renders the internal combustion engine (2) inoperative once a power threshold is exceeded. <IMAGE>

Description

The invention relates to a motor vehicle according to the preamble of the claim 1. As experience has shown, such vehicles can be used for both technical errors as well as operating errors commands to the drive motor ge are given, which can lead to dangerous acceleration processes. Remains for example, the throttle valve or another load actuator of an internal combustion engine Despite the accelerator pedal being released by the driver, it seems in its full-load position, he says does not follow the transition from load to overrun desired by the driver, and the fully working engine can even significantly delay braking.

It is known - see for example DE-OS 20 62 965, F 02 D 17/04 - this danger by counteracting that when the accelerator pedal is relieved of an electrical The throttle valve is forced to close.

So while the technical reasons for the incorrect command to the Drive motor can be counteracted relatively easily, this is in terms of Driver outgoing operating errors considerably more difficult. The DE-OS does 32 38 196, B 60 K 41/20, the proposal for a motor vehicle with automatic transmission This counteracts the forgetting to actuate the brake pedal in stationary operation to act that with very low driving speed and unactuated state of Be Accelerator and brake pedals automatically apply the brakes, however only a small aspect of possible incorrect operation is covered here.  

This solution does not cover, for example, the not uncommon case that the Driver makes a mistake of the brake pedal with the accelerator pedal. Such a mix-up, that is, instead of pressing the accelerator pedal the brake pedal, can be psychologically justified, for example by the fact that the driver suddenly has to make an emergency stop and, if necessary, supported by the current position of the foot above or on the accelerator pedal, in the egg le refrains from moving the foot to the brake pedal. The pedalver described Change can also be made by a seat that deviates from the usual driving position attitude of the driver may be caused, for example when he looks back or sitting in a vehicle he is not used to. Another cause of the pe Swapping the dal can result in the foot slipping off the brake pedal onto the accelerator pedal can be seen.

As these introductory remarks already show, there are a variety of causes for an erroneous actuation of the accelerator pedal instead of the brake pedal, see above that such a pedal mix-up will also occur relatively frequently. You can too a serious danger not only to the vehicle occupants, but also to others Road users, as generally speaking, apply the brakes in in all cases only in the face of an obstacle (or a required speed reduction) is carried out, i.e. a Be triggered by a pedal mix-up acceleration process leads to an accelerated approach to the obstacle.

In this context, the fact that that the driver as soon as he notices that the pedal actuation he has carried out does not lead to the intended vehicle deceleration, an even more powerful actuation exerting force on the putative brake pedal, which accelerates process becomes even more intense. Found in appropriate accident vehicles the bent accelerator pedals are very meaningful in this context strong.

At this point it should be inserted that such pedal mix-ups with their dangerous consequences for both manual and automatic transmissions equipped motor vehicles occur. Is the vehicle composed of the - desired ten - Standstill in motion, for example due to inclination of the road or as a result the peculiarities of the automatic transmission, and the driver confuses the brake with the accelerator pedal, which he will usually press down hard, so can cause dangerous acceleration regardless of the transmission type process.

The invention is therefore based on the object of a motor vehicle according to the waiter concept of the main claim to create against the adverse consequences of confusing the brake pedal with the accelerator pedal is secured.

The solution to this problem according to the invention consists in the characteristic features len of the main claim, advantageous training and further developments of the invention ben the subclaims.

Understandably, the invention includes the additional use of the Stan of the devices and arrangements described in the art, for example for coercion close the throttle valve with the accelerator pedal released or for automatic brake control operation in crawl mode with automatic transmissions is not sufficient. Also an adjustment of the Ignition timing in the late direction can be provided in this context.

The invention is based on the knowledge that the actuation of the brake pedal in particular especially in the case of full or panic braking with significantly larger foot forces follows as the accelerator pedal is pressed, even in the case of full load or the accelerator pedal kickdown position. It is therefore possible to use the force threshold, for the actuation of the accelerator pedal, the Be acceleration command ineffective switching device is specified, for example wise to choose 200 N above the foot force to move the accelerator pedal in full load or kickdown position is required.

As a rule, the driver has to correct his command, ultimately moving the driver's foot from the accelerator pedal to the Brake pedal, requires a relatively long time, the measure according to claim 8, näm Lich the initiation of a braking process by the accelerator pedal assigned te switching device, particularly advantageous. So the driver stands for normal Driving operation for the desired initiation and dosing of braking operations in the usual way Way the brake pedal is available, and only in the event of pedal mistake and never Depress the accelerator pedal with a foot force that is about that for an emergency stop on the Brake pedal corresponds to the actuating force to be exerted via the accelerator Shift pedal associated switching device triggered a braking process.

As already explained, the invention assumes that usually on the brake dal significantly greater foot forces are exerted to initiate braking than on the accelerator pedal to accelerate the vehicle. But you want here  also take into account only isolated extreme cases, such as egg Nem critical overtaking, you can also according to claim 9, a Ge Introduce the speed threshold for disabling the drive motor. Then is the effect of the measures according to the invention on the - relatively low - Ge limited speed range, in which pedal mix-ups are particularly dangerous Chen situations can lead, while in the existing overtaking Speed ranges, even the highest forces exerted on the accelerator pedal Disabling the drive motor.

The advantages of the measures according to claim 13 lie in the same direction According to driving experience, smaller drivers exert lower actuation forces on the pedals as a great driver. The driver size and thus the level of the pedal pedal to be expected Employees find their expression, as it were, in the form given by the respective driver setting of the driver's seat. For example, using a potentiometer this seat setting, especially that in the vehicle hanging direction, detected and for corresponding setting of the force threshold for actuating the switching device be used.

So far, the case of a "real" pedal mix-up, for example as a result of Abrut the driver's foot from the brake pedal to the accelerator pedal, considered wor the. But it is also possible that the driver is mistaken in a particular situation instead of just the brake pedal, both the brake and the accelerator pedals. If the accelerator pedal is only partially depressed, it is invented Switching device according to the invention is not yet activated, and the drive motor is working the braking device activated by depressing the brake pedal. This disadvantage, which accordingly arises in a special case, is invented avoided by the measures of claim 15, the hardly additional tech African effort require, since they the already existing brake light switch Can use motor vehicle.

In general, there can be general pointers to this regarding the cost of the invention sen that usual sensors for speed and speed or the like and usual measures to influence the effect of the drive motor, for example as the interruption or adjustment of the ignition or a corresponding Change in fuel supply, can be used, so that in detail need not be received.  

The time at which the switching device is reset is important, that is Ultimately, the possibility of using a vehicle drive effective again to drive the drive motor. Claim 19 is based on the idea that not any - if necessary only brief - reduction of those acting on the accelerator pedal Foot force to values below the force threshold lead to this reset may, but that this is a completely new operation of the accelerator pedal should be required. According to claim 19, this is achieved in that the acceleration must first be returned to its empty gas position; for control or An empty gas contact on the acceleration serves as a corresponding reset signal transmitter pedal or a part connected to it in motion.

Several embodiments of the invention are described below with reference to the drawing explained, the figures of which are of interest here schematically or as block diagrams the parts of a motor vehicle with a spark-ignition internal combustion engine as an Play the drive motor.

In Fig. 1, the conventional and therefore not to be writing type with ignition pulses supplied via an ignition device 1 four-cylinder internal combustion engine with 2 , the downstream transmission with 3 and the clutch with 4 . Usually, the clutch 4 is in the drive train to the differential 5 , to which the driven wheels 6 and 7 of the motor vehicle are connected.

At 8 , the on-board battery is drawn, which in addition to the ignition system 1 feeds further devices of the motor vehicle to be supplied with current. The ignition sparks in the individual combustion chambers of the internal combustion engine 2 are generated in the usual way by means of individual spark plugs 9 , 10 , 11 and 12 . The application of the individual spark plugs with ignition energy also takes place in a conventional manner via an ignition distributor which is contained in the ignition system 1 .

The motor vehicle is equipped with the accelerator pedal 13 and the brake pedal 14 . The accelerator pedal 13 is in the usual and therefore not shown manner with a throttle flap in the intake manifold of the internal combustion engine 2 in drive connection, while the brake pedal 14 is also not shown, since common connec tion means with the wheel brakes of the motor vehicle is connected to transmit power. The two pedals 13 and 14 lie in a known manner in the lower bulkhead area of the vehicle next to each other, the accelerator pedal 13 being arranged to the right of the brake pedal 14 and somewhat behind it. It is irrelevant to the invention whether the pedals are standing or hanging.

Without the measures according to the invention, there is a risk that, if the accelerator pedal 13 is pressed down instead of the brake pedal 14, instead of a braking process that is desired or even necessary, an optionally dangerous acceleration process is initiated, since instead of the brake, the throttle valve, in the opening sense, is operated. Taking into account the fact that the driver actuates the brake pedal at least as a rule with a substantially greater Ren foot force than the operation of the accelerator pedal 13 , this is assigned a Schaltvor device 15 , the two contacts 16 and 17 by means of the then in its end position pivoted accelerator pedal 13 are only brought into a circuit for the relay 18 closing contact when the driver's foot overcomes a force threshold given by the force of the spring 19 . This force threshold is at a higher level of force than the usual actuation forces of the accelerator pedal, namely in the range of the forces otherwise exerted by the driver when initiating full braking.

While in the illustrated embodiment, the force threshold by a few delfeder is generated, this can understandably also by other means, such as Disc springs or by hydraulic or pneumatic means.

As soon as the driver accidentally actuates the accelerator pedal 13 with a force that he would normally only exert on the brake pedal 14 in the event of full braking, the circuit for the relay 18 is closed, the contact 20 of which then connects the battery 8 and the connector Ignition system 1 interrupts, so that the internal combustion engine is put out of operation.

Understandably, it would also be possible to use the contact 20 at another point in the ignition system or to actuate a valve in the course of the fuel supply of the engine 2 .

It may be expedient to adjust the height of the force threshold, given by the spring 19 , to the size of the respective driver, since drivers of different sizes, according to experience, exert different pedal actuation forces. For this purpose, the not shown in detail, since the known longitudinal adjustment device of the driver's seat with the potentiometer 21 is coupled so that when the driver's seat is adjusted in the longitudinal direction of the vehicle at the potentiometer 21 different voltages drop. These voltage drops are used to control the magnetic coil 22 , which exerts a force counteracting or supporting the force of the spring 19 on the contact 16 . This makes it possible to superimpose the force of the spring 19 on the respective position of the seat and thus the size of the driver Kor correction force, so that the force threshold as a result of this force can be adapted to the conditions of the respective driver at the partial forces.

Furthermore, it may be expedient for the switching device 15 to be effective only in a specific speed range, for example at maneuvering speeds, while in a higher speed range (for example driving on a motorway) in which the driver has always assumed his normal sitting position a mistaken pedal the internal combustion engine 2 is not turned off. For this purpose, the switch 24 in which the relay 18 and the switching device 15 contained circuit is opened via the speed sensor 23 of a known type when the upper limit of this speed range is exceeded, so that the contact between the contacts 16 and 17 is ineffective.

Even then, however, the closing of the contact 25 on the side facing the driver's foot of the brake pedal 14 remains effective with regard to the shutdown of the internal combustion engine 2 , so that the internal combustion engine 2 is switched off with each braking operation.

Instead of a complete shutdown of the internal combustion engine can within the Invention also made a significant reduction in machine load (at idle) men.

Another way of rendering the machine ineffective with regard to the vehicle drive is to supply the internal combustion engine 2 as such with its operating means, that is to say ignition and fuel, but to adjust the ignition angle in such a way that the engine load decreases considerably. Finally, it is also possible to leave the internal combustion engine untouched and to provide means which release the clutch 4 when the force threshold on the accelerator pedal 13 is exceeded. In this case te would have to be provided for a speed limit of the engine.

The arrangement shown can be supplemented in that not only the power output of the internal combustion engine 2 is drastically reduced when the switching device 15 is actuated, but that a braking operation is initiated simultaneously via this switching device. This can also be done electrically, for example via an elec tromagnetic slide control in the hydraulic or pneumatic brake system.

The provision of the contact 25 on the tread side of the brake pedal 14 advantageously protects against unwanted acceleration if, instead of only the brake pedal, the accelerator pedal 13 is also detected by the driver's foot and depressed. The contact 25 is also advantageous if, as intended, only the brake pedal 14 has been depressed, but for some reason, for example jamming of the throttle valve, damage to the mechanical connection between the throttle valve and the accelerator pedal or icing, despite relief of the accelerator pedal load and / or speed of the internal combustion engine have not dropped to the expected extent.

As soon as the accelerator pedal 13 has returned to its idle position, the described arrangement is made ineffective by opening the empty gas contact 26 in the circuit of the holding winding 18 'of the relay 18 .

The embodiment of the invention shown in FIG. 2 is fully electronic. This already applies with regard to the setting of the force threshold that takes place with respect to the respective driver's seat position, when exceeded the externally ignited internal combustion engine assumed here is rendered ineffective with regard to the vehicle drive by drastically adjusting the ignition timing in the later direction, for example shifting by 40 to 50 ° crankshaft angle.

The comparator 30 is supplied at its input 31 with electrical signals from a force sensor 32 provided at the location of the accelerator pedal, which are, as it were, actual value signals for the forces exerted by the driver's foot on the accelerator pedal. For this purpose, a pin can be seen behind the accelerator pedal, on which the accelerator pedal is supported in its end position and which is provided with strain gauges or similar elements, the electrical properties of which depend on the deformation of this pin and thus as a function of the change foot forces exerted on the accelerator pedal.

The other input 33 of the comparator 30 are fed via the potentiometer 34 connected to the driving seat, as it were, dependent on the longitudinal position of the driver's seat dependent setpoint signals for the force threshold, when exceeded the internal combustion engine is to be made ineffective with regard to the vehicle drive. These setpoint signals are obtained via a circuit 35 with the said potentiometer 34 and further potentiometers 36 and 37 , which are used to set the force threshold in the extreme positions of the seat, namely the seat very far forward (potentiometer 36 ) and the seat very far behind (potentiometer 37 ), serve. With these potentiometers 36 and 37 , an arbitrary influencing of the force threshold, given by the electrical signal at input 33 , can be carried out to adapt to the individual characteristics of the respective driver.

The output of the comparator 30 is the filter 38 with low-pass characteristic switched on, which, by suppressing only brief dynamic force peaks which are exerted on the accelerator pedal, limits the ineffectiveness of the drive motor to the case of a somewhat longer pending actuation force for the accelerator pedal which exceeds the force threshold. Such short-term dynamic force peaks have their cause less in a confusion of gas and brake pedal than in short-term mass accelerations.

The output signals of the filter 38 , which thus signal the presence of an unwanted actuation of the accelerator pedal, are fed to the input 39 of the logic element 40 with AND characteristics. This logic element has the further input 41 , which is used to apply a speed condition for the ineffectiveness of the drive motor. The essential component of the subcircuit used for speed detection is the further comparator 42 , the input 43 of which is fed from the tachometer 44 via the digital-to-analog converter 45 analog signals for the actual speed of the vehicle. The comparator compares these signals with its other input 46 supplied analog setpoint signals for the upper speed limit of the speed range, within which the machine is to be deactivated if the accelerator pedal is not actuated. The setpoint is set on the potentiometer 47 .

The switch 48 allows the speed limit described to be switched on or off.

If a faulty accelerator pedal actuation is signaled at the input 39 of the link 40 and the presence of the relevant speed range is signaled at the other input 41 of this link, there is a signal at the output of the link 40 which is supplied to the flip-flop 49 as a set signal. The flip-flop 49 then supplies a drive signal to the first input 50 of the further logic element 51 with AND characteristics, which is supplied to the device 52 for taking back the ignition, that is to say drastically adjusting the ignition timing in the later direction.

In this embodiment, such a ignition redemption takes place only if simultaneously a Si gnal supplied for the other input 53 of the further linkage member 51 that the engine is operating with an above its idle speed lying speed. This is to prevent the machine from stalling in this exemplary embodiment, which can occur at low engine speeds due to such a drastic reduction in ignition.

This speed signal is generated by the third comparator 54 , the inputs of which are supplied, on the one hand, with an analog signal for the actual value of the speed obtained from the motor speed sensor 55 with a downstream digital-to-analog converter 56 and a setpoint signal for the idling speed set on the potentiometer 57 , only if the actual value signal exceeds the setpoint signal, the further link 51 is fed a signal at its input 53 .

The entire arrangement is reset via the flip-flop 49 , which, when the accelerator pedal has returned to its empty gas position, is supplied with a reset signal via the switch 58 which then closes.

FIG. 3 shows the block diagram of the device for ignition retraction designated 52 in FIG. 2. Here, too, usual building blocks are used, so that their description is not required in detail.

In the way of the ignition pulses between the pulse generator, here a Hall sensor 60 , and the ignition amplifier 61 one recognizes the electronic switch 62 , which is flipped through the Si signals of the further link 51 ( FIG. 2) into the interrupted operating position 62 '. In this case, the direct connection between the components 60 and 61 is prevented and the shift register 63 is switched on, which, driven by the frequency multiplier 64 , at its outputs relative to the pulses coming from the Hall transmitter 60 by about 50 to 60 ° crank angle in the direction of later shifted pulses outputs the ignition amplifier 61 .

Finally, in FIG. 4 the output of the flip-flop 49 (see FIG. 2) is indicated at 70 , the switching up to this point is therefore identical to that according to FIG the ignition timing change over a between the ignition pulse generator 71 and the ignition amplifier 72 switched phase shifter 73 , which is controlled via the speed controller 74 so that a number between idle speed and lower idle speed limit ("stall speed") is an engine speed. The connection of the controller 74 to the flip-flop 49 ensures that this only happens when the force threshold described is exceeded. The comparator 75 provides the difference between the desired and actual values (to ^n, and ⁿ⁾ of the engine speed corresponding signals to the controller.

In conclusion, it should be pointed out that the invention also applies to non-combustion engines toric drives, i.e. for example in electric motors, can be used Lich whenever there is a risk of confusing the pedals with the ones described there are dangerous consequences.

Claims (19)

1. Motor vehicle with an accelerator pedal for a drive motor and a brake pedal, characterized in that the accelerator pedal ( 13 ) is associated with such a design that its actuation the drive motor ( 2 ) ineffective with regard to the vehicle drive switching device ( 15 ) when actuated Applying a force threshold exceeding the foot force exerted on the accelerator pedal ( 13 ) for acceleration requires foot force. 2. Motor vehicle according to claim 1, characterized in that the force threshold et wa is at the level of force exerted on the brake pedal ( 14 ) during full braking. 3. Motor vehicle according to claim 1 or 2, characterized in that the drive motor ( 2 ) is rendered ineffective by influencing at least one of its operating variables. 4. Motor vehicle according to claim 3, characterized in that in a fremdgezün Deten internal combustion engine as the drive motor this is made ineffective by ignition timing change ( 52 ). 5. Motor vehicle according to claim 4, characterized in that means in the manner of a speed controller ( 74 ) are provided which regulate the number of rotations of the internal combustion engine to a value between idle speed and lower idle limit speed via the ignition timing change. 6. Motor vehicle according to claim 4, characterized in that a shift register ( 63 ) is switched on for ignition timing change in the path of the ignition pulses. 7. Motor vehicle according to claim 1 or 2, characterized in that the drive motor ( 2 ) is made ineffective by interrupting its drive connection with the driven vehicle wheels ( 6 , 7 ). 8. Motor vehicle according to one of claims 1 to 7, characterized in that the switching device ( 15 ) triggers a braking operation for the vehicle when it is actuated. 9. Motor vehicle according to one of claims 1 to 8, characterized in that a speed discriminator ( 23 ) is provided such that the drive motor ( 2 ) is only made ineffective at vehicle speeds lying in the maneuvering range. 10. Motor vehicle according to one of claims 1 to 9, characterized in that a speed sensor ( 55 ) for suppressing the ineffectiveness of the drive motor ( 2 ) is provided at idling speed. 11. Motor vehicle according to one of claims 1 to 10, characterized in that the switching device ( 15 ) behind the accelerator pedal ( 13 ) protrudes into the movement path described by this after reaching the full load or kickdown position. 12. Motor vehicle according to one of claims 1 to 9, characterized in that the switching device ( 15 ) on the front of the accelerator pedal ( 13 ) to orderly, designed for the force threshold switch. 13. Motor vehicle according to one of claims 1 to 10, characterized in that the switching device ( 15 ) means ( 21 ) for the dependent on the set driver's seat position-dependent setting of the force threshold are assigned. 14. Motor vehicle according to claim 13, characterized in that the means contain a comparator ( 30 ) to which a setpoint signal dependent on the driver's seat position for obtaining the force threshold and an actual value signal for the foot force exerted on the acceleration pedal in each case are supplied. 15. Motor vehicle according to one of claims 1 to 14, characterized in that the brake pedal ( 14 ) is associated with a further switching device ( 25 ) which, when the brake pedal ( 14 ) is actuated and there is no reduction in engine load and / or engine speed, affects the effectiveness of the drive motor ( 2 ) at least reduced in terms of vehicle drive. 16. Motor vehicle according to claim 15, characterized in that at least one of the operating variables of the drive motor ( 2 ) is influenced. 17. Motor vehicle according to claim 15, characterized in that the Antriebsverbin extension between the drive motor ( 2 ) and the driven vehicle wheels ( 6 , 7 ) is interrupted. 18. Motor vehicle according to one of claims 15 to 17, characterized in that the further switching device ( 25 ) contains the brake light switch. 19. Motor vehicle according to one of claims 1 to 18, characterized in that the switching device ( 15 ) is assigned an empty gas contact ( 26 ) for resetting.