SE453813B - VEHICLE DRIVING CONTROL - Google Patents

Description

453 813 10 15 20 25 30 35 measures. But in bad weather conditions can the vehicle is driven through mud or ice and can nationally lagging occur, as well as when one of the wheels lose drive and start rotating too fast, which is hereinafter referred to as a lag condition.

It has therefore been advantageous to introduce locking mechanisms. more or other control devices to eliminate it excessive difference in speed of the different outgoing shoulders. Mechanical locking mechanisms for coupling the main drive shaft to an output shaft of a differential has been used in the truck industry and examples of this can be found in U.S. Patents 3,261,901 and 3,390,593.

Mechanical locking devices have also been used in intermediate variants for road vehicles with dual drive axles according to U.S. Patent No. 2,870,853.

A relatively sensitive electronic control unit for limiting said lag differences are proposed in US U.S. Pat. No. 3,138,970, while U.S. Pat. No. 3,706,351 shows examples of an electromechanical system selective brake control system for limiting the speed the number difference between a pair of wheels on a vehicle.

By locking two shafts in a differential mechanism the group of three axles, consisting of the the shaft and the two output drive shafts, are generally locked expressed all three axes and eliminates differential function. The terms lock, lock condition or locked condition generally refers to the condition in which the differential mechanism, which engages the main drive the axis of the two output shafts, is brought to the with the result, that then the two output shafts rotates at the same speed and torque emitted from the engine torque is transmitted to both the output shafts in accordance what is required with regard to the external 10 15 20 25 30 35 455 813 5 stand, to which each output shaft is exposed.

Reading can e.g. achieved manually by the driver when sensing a lag condition or can achieved by automatic control, e.g. according to the above U.S. Patent 3,138,970. control can also be done in other ways than by locking a vehicle differential, whereby in American proposed 3,706,351 brake control system make an alternative solution to the problem; Electronic couplings can thus be used to control means for to eliminate or at least reduce the size of the dragging to values within acceptable limits.

The electronic control unit reacts in particular to sensed speed inputs and produces continuous monitoring and control. Such continuous monitoring devices are sensitive to repeated change of the steering insofar as the speed of the output shafts has tendency to become synchronous almost immediately after locking, so that the error signal disappears, before the vehicle has in fact come out of its backlog stand. The electronic control unit continues to monitor the output shaft speed and the error signal will, if the vehicle did not in fact come out of its original lag condition to release the locking device, to be generated again and re-supplied to the control locking device.

Fluctuations can e.g. appear in the drive system with a high frequency of between l - 3 Hz. Such fluctuations can have a very adverse effect on the vehicle through repeated stresses on the drive components and can affect on the vehicle operator, in particular if the steering system sets to change periodically and the vehicle does not pass' over the part of the roadway which has a lagging the condition. 10 15 20 25 30 35 453 813 The invention is based on the task of eliminating the disadvantage prior art through the development of a lag control device, which is insensitive to rapid changes and in instead maintains the locked condition for a pre-determined timed time. The control unit according to the invention is particularly reversible coupling mechanisms of the differential type to provide coming of an extended and fixed lock-in period after too high difference in speed on the output side. IN The invention therefore relates to a device for use on a vehicles with a main drive shaft and a first and a second output axle, which are drivable for transmitting drive torque to wheels on the vehicle, as well as a device for coupling the drive shaft to the output shafts, comprising a) a sensing device of the relative rotational speed of the output shafts, b) a control device, which is activatable in dependence on that of the sensing device detection of lag conditions and includes a device to eliminate the lag condition. The device comprises c) a device for activating the device for eliminate the lag condition and generate a control signal, d) wherein the activating device operates during a pre-determined timed after its activation and e) a security timer, working for a fixed period of time before the end of the time determined time to deactivate the control device, if the control the signal still remains at the set time. At In a particularly suitable embodiment, the control unit operates in one differential mechanism for interlocking two of the above groups of axes depending on the sensing means. The invention is particularly applicable to vehicles with dual drive axles together with an intermediate differential with a device such as a fork and occlusion combination to allow a clutch collar slide into engagement for locking the input main shaft on the intermediate differential at one of the output axes thereof differential or for locking the two output shafts.

The invention is described in more detail below in exemplary form with reference to of the accompanying drawing, where Fig. 1 shows a block diagram to illustrate the principles for the electronic control coupling according to the invention, 'p 10 15 20 25 ~ 30 55 453 813 Fig. 2 is a top view of a cab and the chassis for one truck with an intermediate differential according to the invention, Fig. 3 is an enlarged view of portions of the intermediate the material according to Fig. 2, Fig. U is a block diagram of a particularly suitable embodiment; form of the control coupling according to the invention and Figs. 5A and SB are detailed wiring diagrams for the circuit shown in FIG fig fi l! showed the clutch.

Fig. 1 shows the block diagram of a lag control coupler. according to the invention, wherein it is generally teoknade control unit is set up to receive electrical signals from two sensors not shown, which detect rotational the speed of each of the two output drive shafts.

One sensor can e.g. detect the rotational speed of the input main drive shaft at the input of a differential ferential; while the other sensor may be set up to detect the rotational speed of one from differentiating smooth output shaft. The donors themselves may be of conventional nell type such as magnetic sensors, which emit a pulse when passing each tooth on a rotor attached to the drive shaft.

In this case, the frequency of the incoming signals is proportional to the rotational speed of the shaft. The sensed the signals W1 and W2 are transmitted via input lines l1 and 12 to a differential stage lü, which measures the difference between the two signal frequencies. The step l fl can e.g. include a comparator to compare the difference between the absolute values of the two inputs, these ab- market values are proportional to their respective frequencies, with a reference value which in turn can by adding the two inputs and multiplying cation with a reference value, e.g. 0.05, which is suitable for the type of comparator used. The step lü decides thus an output signal via line 15, only if the difference 10 _ 15- 20 25 30 35 4.53 813 6 - the rotational speed of the axles is greater than a certain permissible lag level. Some lag is of course acceptable as a result of normal operating attitudes towards the vehicle in order to e.g. enable passage through curves and over uneven terrain and achieve fit to different tire radii. ' The output signal on line 15 can be called an error or difference. signal, which indicates an excessive difference in speed of the shafts and is applied two earlier T1 at 16 and T3 at 18. The timer T1 emits an output pulse after a nominal switch-on delay of the order of 0.25 - 0.5 second and is intended to reduce incorrect activation in the presence of initial wheel lag. After this switch-on delay, the output signal T1 is fed from the timer 16 to the input the position input on a bistable rocker stage 19, which dan emits an output pulse from its output Q. The output pulse is fed via a line 20 to a power amplifier 21, which dan drives a control device or solenoid 22.

The control device 22 is intended to actuate means for eliminate the lag detection detected by the sensors stand. A magnetic coil such as the control device 22 can be used turned to displace a clutch collar and thus put a differential mechanism in the locked state. One such application case will be described in more detail below. dan. The control device 22 can also be used in combination with a selective brake control system of the type described in U.S. Pat. No. 3,706,351, or at a vehicle with four drive wheels of the type described in U.S. Patent 3,557 GBÄ, to bring one coupling to engagement and thereby provide propulsion at the front axle of the vehicle. _ The output signal from the amplifier 21 is also applied to a timer. be T2, which is also denoted by 23. Timer T2 10 15 20 25 30 35 453 813 is a basic period employee and provides a precautionary matched time period e.g. of the order of 30 - 60 se- customers, during which the control device 22 is activated.

At the end of this predetermined period of time, the the sensor T2 an output signal to an OR gate 24, as in its turn emits an output signal to the reset terminal on tilting step 19. When resetting, the output Q on the tilting step 19 low level, so that the control device 22 is disconnected las. The reset of the rocker stage 19 can also take place, with the timer T3, namely the safety timer ceases to operate, since the output of the timer 18 also an input is applied to gate 2ü. Timer T3 set read in particular for a longer period of time than the period of time T1 and less than a time period T2. The safety timer has the task of disconnecting the control device 22, if the lag condition has not been eliminated after the period T3. The time period T2 can e.g. set to 30 seconds and the time period T3 to 15 seconds. If the error the signal on line 15 still appears after 15 seconds, the timer T3 resets the tilt step 19, so that the control device 22 is disconnected. The early T3 works provided that the previously identified the towing state has been eliminated after the time period T3, so that the error signal on line l5 should no longer available. If the error signal still occurs, is set that some error has occurred e.g. a donor fault or fault of the locking mechanism. It is in any case desirable to disconnect the control device and provide an indication to the operator of the fault condition. Tidspe- period T3 can be set to any value within the door determined by T1 and T2. The time period T2 can for example amount to 30.5 seconds and the time period T3 to 30.0 seconds. In such a situation, the timer T3 may have a very narrow gap from 30.0 to 30.5 seconds and can thus be used to eliminate detection of external from resulting error signals due to strong vibrations tion and the like. ' 10 15 20 25 30 35 453 813 The particularly suitable embodiment of the invention for use at an intermediate differential on a vehicle with double drive shafts is shown in Figs. 2 - 5. Fig. 2 shows from above a cab 20 and a chassis 22 'for a truck.

The chassis 22 'is supported by a drive unit with a front rear axle 2H and a rear rear axle 26. ' Torque from the vehicle engine is transmitted by means of drive shaft 30 to an intermediate differential 32, which is attached to a housing 31, which divides this moment between a front rear differential BU and a rear rear differential 36. The drive shaft 30 is connected to the input 38 at intermediate the differential via a universal joint H0. Mellandiffe- The differential 32 divides the torque acting on the input 38. the first output shaft H2 and a second output shaft walking shaft HÄ. According to Fig. 3, the output shaft is driven H2 directly by means of gears on the left of the differential 32 side, while the shaft HH is driven by a series of gear gears H5 - H7, which in turn are driven by. gears1 'on the right side of the differential 32. The outgoing the shaft UH causes a gear to rotate, which drives the ring gear on the front differential BU. It expired the axis Å2 is connected via a universal joint H8 a drive shaft 50, which in turn drives the ring gear on it rear differential 36. A collar 52 is wedged on shaft 42 and is axially movable relative thereto shaft by means of a fork (not shown) and can be moved to left in Fig. 3 for engagement with teeth SO on the hub for a downshift gear # 5. When the collar 52 is engaged with the teeth SU, the gear H5 and the shaft H2 are mechanical locked and rotating at the same speed. Differentia- 32 is prevented from changing the equal speed the split, until the collar 52 is no longer engaged with cogs SU. fia A representative dual shaft unit with an intermediate differential and a locking mechanism are disclosed in U.S. Pat. 10 15 20 25 30 35 453 813 ten 2 870_853 ..

Two sensors 56 and 58 are attached to the differential body 31, wherein the sensor 58 responds to rotational movement of teeth on the gear H5 and thereby senses the output rotational speed of the shaft 42. Sensor 56 responds too rotational movement of a toothed rotor 60, which is attached to the cover 32 of the differential and thereby senses the rotational speed of the drive shaft 30. Sensors 56 and 58 provides output signals via lines 62 and 6Ä to the control unit 66, which is located on the cover 31 of the differential 32.

When sensing the speed difference depending on the signal The lines 66 and 6D emit the control unit 66 output via line 68 to an air solenoid valve 70, which works in a conventional way and moves the collar 52 and locks the differential 32. In the case of a lock condition gives the control unit 66 a signal to an indicator lamp 72, which is visible to the driver.

The control unit 66 is powered from a brake light circuit and means for deactivating the locking mechanism at the actuation of the vehicle brakes. Fig. 2 shows a battery ri in YH connected to a stop light producer 76, which closes depending on the operation of a foot pedal 78.

By connecting the control unit 66 to the brake light circuit then it is also possible to detect a condition with wiring breakage. In this case, it would open the brake circuit detected by the controller 66, which would deactivate the lock the process.

Fig. U is a block diagram of the main components of the control unit 66. Inputs from sensors 56 and 58 are fed through wires 62 and 6U to separate signal-forming stages 80 and 82. These steps 80 and 82 convert the sinusoidal the input signals to rectangular waves, which are then fed via lines 8Ä and 86 to controlled trip stages 88 and 90. Steps 88 and 90 are alternatively controlled by one 10 15 eb 25 '30 35 453 813 10 oscillator 92, so that a pulse is emitted either via an output line 9H or 96. Lines 9ü and 96 are connected bound with inputs on an OR gate 98, the output of which are connected via a reversible counter 100 via a 102. The signal on line 102 is characteristic of the proximity pulse from either sensor, wherein the pulse frequency is directly proportional to the axes 30 and H2 rotational speed, which is measured by the sensors 56 and 58. Os- the chillator 92 also emits a signal via line 104 to counter 100, so that the signal on line 102 can be considered derive from either step 88 or step 90. One the trip step was used to count the counter 100, while the second trip step causes the reduction Bill. The signals via line 1OU on oscillator 92 essentially allows stepping of the counter 100 either up or down depending on the sensor, which is in feature. The counter 100 is preset e.g. to the binary ra value Ä. The countdown of the counter 100 indicates that one sensor, e.g. sensor 56, emits several signals per unit of time than the other sensor, e.g. the sensor 58.

Enumeration of the counter 100 indicates the opposite state. Time the countdown and countdown gap is determined by a ~ oscillator 110 and sample 112 generator 112. Time the door can e.g. be of the order of 200 milliseconds customers. If a zero count condition is reached within the sampling time slot, an error signal is emitted via line llü from the time on the counter 100. If a winemaker 8 is reached within the time slot at the counter 100, one is output in the same manner error signal via line llü. The error signal is applied to one for bistable bistable rocker step 116 and one input time on a NAND gate 118. The error signal serves to set the step 116, so that this from its output Q emits a signal to a drive stage 120 via line 122.

The output signal from the drive stage 120 supplies a magnetic coil 71, which drives the collar 52 on the intermediate differential for the locking of the same. The drive stage 120 also provides visible 10 15 20 25 50 55 453 813 11 indication for the vehicle driver by means of indicator lamp 72.

Rocker step 116 is reset upon receipt of a return position pulse from a counter l2H after the output of a in the counter-12H preset time, this counter i- is started when the error signal occurs. The counter is activated thus begins to count upon receipt of a count activation signal from the rocker stage 116 via a line 123. The reset signal from the counter l2ü is applied to the step 116 via a line 128, this reset being signal in the present case will occur 'H35 seconds after the error signal appears on the line llü. The control unit can of course be modified to provide fixed time periods of different durations, which retreats exceeds about 20 seconds with respect to other embodiments of the invention. A second exit on the counter 12U is connected to it via a line 130 the second input of gate 118, this second output corresponds to the safety timer T3 shown in Fig. 1. Again, the count activation signal was used on the line 126 to form the count start reference for activation of the counter l2H.

The output of gate 118 was used to set a bistable safety toggle step 136, provided that the error signal on line llü occurs at the same time as the counter l2ü emits a signal via the line 130. This conditions, in fact, require that the error signal occur at time T3 according to the designation in Fig. 1. At input position of the timer 136, a signal is emitted via a l38 to a drive stage lH0, which in turn activates an indicator lüü. An output signal from rocker stage 136 via line 125 to the counter 100 also serves to activate the control unit so that the drive stage 120 no longer have the opportunity to be active.

Fig. 5A and SB show wiring diagrams for the parts which can be found in the block diagram shown in Fig. 4. The signal 10 15 20 25 30 35 453813 12 forming steps 80 and 82 are constructed in the same manner, for only one step will be described. It says The forming step 80 comprises a voltage comparator 180, a zener diode D1 and filter network, which consists of stands and capacitors. Two resistors form a voltage divider, and forms a reference voltage for one the input of the comparator 180, the second input of which is applied the signal from the sensors. Conventional donors can use das in the form of sensing elements with variable magnetic reluctance, which emits a sinusoidal signal to the stage 80. The output of comparator 180 is in fact a rectangular wave and is applied to the trigger step 88. it is assumed that the output signal from the comparator 180 is supplied directly to the input of the trigger stage 88 via three NAND gates 380, 382 and 38U. Out- solution step 88 comprises a bistable rocker step 190 of the D-type, which is set when the output signal is received from the comparator 180 from its output emits a logic high level signal depending on this. The output Q on the goat 19O is connected to one input on one by four inputs provided AND gate 192, the other three inputs of which are formed by the output of a counter described below.

Step 88 further comprises a drive step 19h, which feeds one NAND gate 196, whose output signal is a positive pulse with one width of about 20 microseconds and is applied to the output line 9U from step 88. A similar pulse to one duration of 20 microseconds is transmitted via the line 96-from step 90. Wires 94 and 96 are connected with an OR gate 99, which consists of one with an inverted 202 connected NOR gate 209. The output signal from gate on the 99 is added the counter 100, which e.g. can be off preset binary type.

The oscillator 92 may comprise a sampling oscillator 210, which is connected to a four-bit binary counter 212, which via lines Zlüa, b, c and d emit a code, of which lines 21lHa - c transmit binary codes, which identify 10 15 20 25 30 35 453 8-13 13 such as A, É and Ö, which are supplied as authorization codes the gate 192 is raised in the trip step 88. In the same way forms state codes Ä, É, Ö input signals to the corresponding AND gate in the trigger stage 90. The various the stand codes ensure that only one of the triggers steps 88 and 90 will be controlled at a time. 0s- the chillator 210 can e.g. be intended for H0 kHz, while the sampling frequency generated by the counter 212 for var and one of the trigger steps 88 and 90 may amount to for example about 5 kHz. The sampling time is selected to be worth longer than the highest expected sensor frequency, which is in the range 0 - 1 kHz. The counter 212 emits an output signal via line 10U to the control input on the the counter 100. The counter 100 will consequently count the things up or down depending on the condition of the control input signal on line 10U, which is continuously from one state to another synchronously with the control of the trigger steps 88 and 90.

Fig. 5A also shows the oscillator 110 and the sample door. generator 112. Oscillator 110 emits a pulse with a pulse period of 13.3 milliseconds from its output terminal. This pulse is applied to generator 112 via line 220. tower 112 may comprise a division stage and is arranged dividing the incoming signals by 16, so that an output signal with a nominal duration of 200 milliseconds appears on line 222, which supplies one of the time on a NAND gate 22H. Via the second entrance on gate 22N, the gate is prepared by the output of a NAND gate 226. The output signal from gate 22H is applied counter 100 and presets this counter to the near state H was the 200th millisecond. Consequently the counter 100 has a slot for receiving the speed pulses via line 102 for a period of 200 milli- seconds, before it is reset to the preset near the value U. Under this gap of duration 200 milliseconds, the counter 100 can either count down to 10 15 20 25 30 35 453 813 lü value 0 or count up to the value 8 depending on the difference in frequency between the pulses, which via 62 and 6ü are fed from the sensors. If a binary calculation state of 8 is reached, an output pulse is emitted via a line 230 from the coaster 100 to one input on an AND gate 232. If the count state 0 is reached, the output signal is output the counter 100 via a line 23ü and the inverter 236 to the second entrance on gate 232. The exit on gate the 232 is connected to a NOR gate 238, which emits one error signal via line 114. The error signal has a high level, i.e. is a logic 1, when the output of the counter 100 reaches either the binary count state 8 or the secondary close to the count state 0, whereby a considerable difference in rotational speed of the two measured axes indi- keras. The high-level error signal on line ll the rocker stage 116 is passed via an inverter 280, whereby the goat 116 comprises cross-cut mmm gates 2142 and 21:14, wherein the output from the gate 2Ä2 is applied to an inverted edge drive stage 2ü6. The output signal from the drive stage EH6 ma- is taken via a line 122 to the drive coupling 120, which consists of transistors 150, 152 and 15H. A magnetic coil 71, energy is supplied from the drive coupling 120 as well as input the indicator 72 for indicating a locked state.

The output signal from gate 2U2 is applied to the count activation the clamp on the counter 122, which can be preset for a pre- fixed period or a fixed period of 727 or H35 seconds and which after the end of this time period riod supplies a clock signal via lines 128 and 130.

The l2U counter is set in the present case for a fixed time period of N35 seconds. Line 128 contains one RC circuit 255, which provides a time delay of the circuit for 1/2 second. The signal on line 128 gets a high level at the end of the preset time period of e.g. H35 seconds, during which the lock condition is maintained. Un- where the preset time period comes the lock state to be maintained regardless of the value of the error signal on 10 15 20 25 30 35 453 813 15 the line llü, since the rocker stage 116 remains blocked, until it is reset by the delayed time signal. period on the line 128. For this purpose, the clock signal on line 128, which is delayed by half a second by means of the circuit 255, to one input of a NAND gate 256, which with its output signal supplies an input to gate on 2U2. The second input of gate 256 is applied to one clock signal via line 126 from oscillator 110. the 256 was used to prevent any rush state of the tilt step 116. The exit on the gate 256 is operated at a low level, when the clock pulse on line 126 and the delay time resulting from line 198. the signal occurs simultaneously. When the exit on the gate 256 has a low level, the gate 2H2 has a high level, so that step 2U6 is brought to low level and the solenoid 71 and indicator 72 is deactivated. Due to the output signal from gate ZU2 with high level is reset at the same time ren l2U.

The clock signal on line 130 is the same signal as the nal on line 128 but is not subject to delay.

The clock signal on line 130 is applied to gate 118 and thus the rocker stage 136, which consists of two cross-coupled NAND gates 260 and 262. Gate 260 also receives one signal via line 26U from a brake circuit 270, which is written in more detail below. Gate 260 provides a safety signal FS, which normally has a low level in case of inactivity and transition to a high level or a logical 1 during a security condition, when the clutch is to be deactivated. If e.g. the error signal on the line llü still occurs with high level at the time, the clock signal is generated on the l30 half a second before the delayed signal on line 128, the output of gate 260 will get low level, i.e. logical 0. At the same time receives the output signal from gate 262 low level, so that the signal Fš gets low level, i.e. passes to a logic 0. The signal FS from gate 260 is applied to one input of gate 266 i 10 15 20 25 30 35 453 813 16 Fig. 5A. The gate 226 in turn emits another signal gate 22U, which continuously presets the counter 100 and thus deactivates the control clutch. The signal from gate 262 forms a low level output signal on the line 139 to drive stage 27U. The output signal from the drive stage 27U supplies the drive stage 1H0, which consists of transistors 276, 278 and 280 similar to drive stage 120. An indicator lüä is activated when the system is operating in the.

Another measure shown in Figs. 5A and SB is the insertion one of the brake circuits 270 in the device shown in Fig. H.

Brake circuit 270 detects both braking condition and an open circuit condition, which may, for example, be of loose wire breakage or wire breakage. The line 290 is connected between the brake circuit and the vehicle battery and brake lights. When the brakes are activated, the voltage one on line 290 normally to about 13.6 volts. Brake- circuit 270 includes resistors, a capacitor and diodes and further voltage comparators 292 and 29A together with a inverters 296, AND gates 298 and 300 and a NAND gate 302. Three resistors form a voltage divider for feeding one input on the comparator 294, as with its second input is connected to line 290 via a resistance. If the brake switch is operated, appears high level at the output of the comparator 29H at the line 30ü, which supplies the inverter 296 and drives it to low state. The inverter 296 is connected to a NOR gate 306, which brings the output signal on line llü to low level via gate 238. By holding the error signal low level during operation of the brake switch, in this way the locking coupling is prevented from being activated. In- hibernation of locking during braking is desirable to prevent locking at the intermediate differential, which relates to asynchronous wheel rotation during braking. 10 15 20 25 30 35 453 813 17 The brake circuit 270 further enables the detection of an open open brake circuit by means of the comparator 292, which is maintained low level in open brake mode and normal receives a voltage between one third and two thirds parts of the regulated supply voltage, which arise from the bias network with those included in the brake circuit the resistance. During an open brake circuit condition the output signal from the comparators 292 and 29U is the 298, which then feeds the gate 302, which in turn takes gate 300. An output signal on line 264 is applied an input on the gate 260 in the rocker stage 136, so that this is set and generates a high level safety signal in in the form of a logic l. The signal FS presets continuous counter 100 via gate 226 in the manner described above so that further generation of the error signal on the line llü prevented. Toggle step 136 remains activated, until it is reset manually, while the active brakes simply temporarily prevent the ring of any error signals on the line llä via gate 238. As soon as the brake lights are deactivated, get the control coupling in the latter case the opportunity to influence drive 120.

Fig. 5 also shows a clutch 330 for automatic maintenance. search for power supply, which consists of cross-linked NAND gates 332, 33U, inverters 336 and 338 and a NAND grind 3ü0. The coupling further comprises that in fig. 5A vi- said gate 3H2. The voltage regulation shown in Fig. 5A tower emits a regulated output voltage V of about 6 volts. Un- When started, the pulse with a voltage of 6 volts forms one signal PUP, which refers to power supply and occurs during about 2 seconds followed by the time constant provided by comes by means of a resistor and a capacitor. Current food the signal ensures a logic O signal at output the passage on the gate 3fl2, which is supplied via a line 3Nü gate 332. This signal is a means of examination the connection during a current supply process through formation l0 15 20 25 455 813 18 of signals TEST and TÉÉT, which simulates a sensor input by the formation of simulated counting states by gates 380 and 382. A coded signal is also emitted from the counter 212, which is applied to one input on one NAND gate 380. the voltage regulator stabilized, consequently appears After the vehicle ignition has been activated and pulses at the output of a NAND gate 38ü, which are applied * reset rocker step 190 for generating simulated arithmetic condition sampled by oscillator 210 and calculator 212. But the trigger step 90 does not receive any simulated counting states, so that an error signal is generated on the line llü, which is supplied to the gate BRO together with the signal TEST, which resets the clutch 330 and also step 136. The indicator lüü will nevertheless re to be energized for about 2 seconds, which is the period of time during which a signal for current feedback occurs. Then this feedback signal passed to 0, the indicator l fi ü will no longer be energy is supplied, unless a fault is detected in the clutch. The output signal from gate 3N2 was also used for resetting power supply and was used together mans with the signal PUP as a signal to the gates 210, 2H2, 352 and 300 for resetting the counters and the tilting steps, which are coordinated with these gates.

Examples of integrated circuit components¿ that can be used for the coupling shown in Figs. 5A and 5B, is used given in the table below. 10 15 19 Designation of reference 82, 180, 292, 29H 190 196, 192 19ü 100, 202, 2u0, 110 ' ZH2, 118, 256, BBU; 12n 200, 232, 210 112, na 2%, 260, to, 262, 380, 238, 298, 212 336, 270, am 2%, BM, 382, 306 300 338, 296 2UH, 332, '38M Part no LM CD CD CD CD CD LM CD CD CD CD CD 29101 hol; U093 H082 H00? M029 MOM9 555 A023 zero uoho M001 Ho81 453 813

Claims (8)

10 15 20 25 30 35 453 813 20 Patent claims Device for use on a vehicle with a main drive shaft and a first and a second output shaft. son are drivable for transmitting propulsion to wheels on the vehicle. and a device for coupling the drive shaft to the output shafts, comprising a) a device (14) for sensing the relative rotational speed of the output shafts. b) a control unit (19: 66). son is activatable in dependence on the detection state of the lag condition and comprises a device (22: 71) for eliminating the lag state, characterized by c) a device (23) for activating the device to eliminate the lag state and generating a control signal, d) the activating device operating for a predetermined time after its activation, and e) a safety timer (18) operating for a predetermined time before the end of the predetermined time to activate the control device. (19). if the control signal still remains at the set time. 2. Device according to claim 1, characterized in that the coupling device is a differential (32) and that the control unit is activatable for true locking two of the group of drive shaft (30) and first and second output shaft (42. 44) for rotation. Device according to claim 1, characterized in that the vehicle is provided with a front (24) and a rear (26) rear axle for driving the vehicle wheels and a wrench differential (32) for dividing torque between these axles and that the nelland differential with one input is connected down the main fm drive shaft (30) and with outputs_down the output shafts. Device according to one of the preceding claims, characterized in that the safety timer (18) is in operation for a short period of time. Device according to claim 4, characterized in that the time period has a duration of at most one minute. Device according to claim 4 or 5, characterized in that the time period ends simultaneously with the predetermined time. Device according to any one of claims 1 - 6, wherein the vehicle is provided with a brake, characterized by a device (72, 76, 78), which reacts for the activation of the brake and generates a bronze signal. and a device (78) for receiving this brake signal and deactivating the control unit (66), so that this unit is inactive for activating the device for eliminating lag conditions when activating the brake. Device according to any one of claims 1 - 7, wherein the vehicle is provided with a brake light circuit, characterized by a device (290, Fig. SA) connected to the brake light circuit (292) for detecting an open circuit condition and a device (248. 302 , 300) for deactivating the control unit (136) when detecting such conditions. said that the control unit (136) is deactivated when detecting an open circuit condition in the brake light circuit,