DE2251548A1 - VEHICLE WITH BLOCK CONTROL - Google Patents

Description

Dipl. Ing. E. Graalrs - Dipl. Ing. VV. Wehnert

ICelsey-Hayes Company

38481 Huron River Drive ■ _Anwal t _sa kte / 1-2377

Romulus, idi cn. 4 81 7 4, USA

October 20, 1972

Vehicle with locking control

The invention relates to a vehicle with a Locking regulator, and in particular a locking regulator for a wheeled vehicle, which has a manually operated transmission.

When a wheeled vehicle equipped with a hand-operated gearbox for example, gets into a locked or slipping state during emergency braking, there is There is a risk that the engine will stall because the driver cannot disengage the clutch quickly enough. At a standstill Motor fail the various motor-driven accessories, such as power steering and the servo brakes, which work as a function of hydraulic pressure medium, which are carried out by motor-driven auxiliary pumps and booster is supplied. At the same time, if the engine is at a standstill, the engine vacuum can be lost,

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for servo actuation / other additional devices, for example a modulation valve of the blocking regulator, is used. In addition, when the engine was at a standstill, the driving force train and din drive wheels with the braking effect of the stationary Motor is loaded, whereby the lock controller during a regulation of the Bremsvorangs on the assigned vehicle wheels can be seriously disturbed.

With some anti-lock regulators, the brakes are grounded when you step an impending locking condition is cyclically relieved and actuated again in order to prevent the vehicle wheels from locking. When the brakes are released, the vehicle wheels can accelerate again. If, however, the braking effect of the stationary motor v / uring a control cycle of the lock controller on the drive train and the drive wheels is exercised, the re-acceleration of the vehicle wheels can be delayed by the exerted load, see above that the vehicle wheels can be locked despite the response of the lock controller.

In contrast, according to the invention in a vehicle with a hand-operated gearbox and a lock controller die Clutch automatically disengaged by an adjusting device for disengaging the clutch is provided, which upon determination responds to an impending locking condition of the vehicle wheel or wheels. The actuating device can be electrically operated

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"actuated valve," for example a solenoid, "are actuated when a control unit of the locking regulator generates a control or output signal at the same time a signal is generated by which the solenoid is excited to disengage the clutch, so that the engine -during an "impending or occurring stall condition of the vehicle or wheels." is uncoupled. ^J - ■

The output signal is usually the output signal for blocking regulators the control unit uses a flow medium modulation device in such a way that the fluid pressure applied to the brakes is reduced and thereby a Blocking of the vehicle wheels is prevented. When the rotation speed the vehicle wheels increases, .will the output signal switched off and activated the hodulation device, so that the brakes are re-engaged. If, as a result of the brakes being pushed in again, an "imminent." Blocking or slipping occurs, the control input * Hexts an output signal again to release the brakes. Usually several such control cycles occur during a single braking operation. In addition to the advantage that -the Clutch is disengaged when an output signal is generated, It is also advantageous that the clutch during the

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entire braking process and over several such control cycles remains disengaged to prevent undesired engagement and disengagement. According to the invention, this is achieved by a Reached locking stage that keeps the clutch in the disengaged state during the entire braking process.

Overall, the invention provides a lock controller for a wheel drive with fluid-operated brakes and a manually operated gearbox and a clutch, whereby the blocking regulator a signal generator to determine an occurring or imminent locking condition of the vehicle wheel (s), a valve arrangement, responsive to a blocked condition, for reducing the fluid pressure applied to the brakes, as well as a disengaging device, which also responds to a blocked state, for uncoupling the transmission contains.

According to the invention, the engine is thus automatically dependent on an occurring or imminent vehicle wheel lock condition uncoupled. Furthermore, a locking stage is provided, which is activated by the output signal of the control unit of the lock controller is actuated and -the motor is decoupled during a braking process over several lock control cycles State holds. The locking stage can be activated by a switch assigned to the brake pedal or the accelerator pedal turned off. This keeps the engine running during a

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Great braking with multiple brakes Go through pressure release and pressure control cycles, disconnected. In addition, according to the invention, an auxiliary comparison stage can be provided in connection with the locking stage be, which provides a fault indication of the switching stage controlling the release device. Furthermore, the locking stage can be controlled by a switch that is either the .Gas- or the Brake pedal is assigned to be switched off.

Further details and features of the invention emerge from the remaining claims and the following description in conjunction with the drawings. Show it:

Pig. 1 is a schematic representation of a motor vehicle with one designed according to the invention Locking control;

Pig. FIG. 2 shows a circuit diagram of an embodiment of the locking stage shown in FIG. 1;

Pig. 3 a graphic. Diagram showing the brake pressure over the duration of a locking control cycle plotted and also shows its relationship to the blocking control signal and to the locking signal of the locking stage;

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Fig. 4 is a schematic representation of a second embodiment of a Pig. 1 as switch 60 shown reset device for the locking stage.

The locking control is particularly in connection with a Motor vehicle can be used that has a hand-operated transmission and a clutch that can normally be operated by a foot pedal having. The clutch can also be automatically disengaged by selectively actuating a solenoid valve. The blocking regulator itself may be of the type described in U.S. Patent 3,515,440. Such a blocking regulator can either Use in conjunction with the front wheels, the rear wheels, or the front and rear wheels. For the sake of simplicity the lock controller is only described in connection with the rear wheels of a motor vehicle.

According to Fig. 1, the lock controller is one of the rear wheels Associated motor vehicle, the rear wheels being provided with brake drums 10 and wheel brake cylinders 12. Hydraulic lines 14 are connected to the brake cylinders 12 and to a hydraulic line 16 which is connected via a hydraulic line 18 is pressurized by a master cylinder 20. The master cylinder 20 can be of conventional construction and have a Foot pedal 22 can be operated. For modulating the fluid pressure a modulation valve 24 is provided from the master cylinder 20

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seen, which lies between the hydraulic lines 18 and 16. The modulation valve 24 .regulates the at the Radbremsz3? -Relief 12 applied fluid pressure and thus the mode of operation of the brakes. The brake drum 10 associated brakes are of conventional construction and are therefore not described further. The modulating valve 24 may be derived from that disclosed in U.S. Patent No. 3,515, referenced above be described and operated by negative pressure.

The modulating valve 24 is activated by an electrical signal operated, which is generated by an electrical control unit 26. The control unit 26 receives information signals from Sensors 28 which are assigned to each brake drum 10 via exciter rings 30. The exciter rings 30 and the transducers 28 can be of known design, the exciter rings 30 together with the brake drums 10 (and thus with the associated 3 vehicle wheels) and the measuring transducers 28 Feed an electrical, pulsating or alternating current signal via conductor 34 to the control unit 26, which signals the rotational speed of the assigned vehicle wheels.

The control unit 26 determines the rate of change of the signal supplied via the conductor 34 and thus the size the deceleration of the 3-car wheels assigned to the brake drums 10 and generates an output when the delay

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of the vehicle wheels assigned to the brake drums 10 Reached predetermined value, which is associated with an existing or imminent blocking state of the drums 10 Vehicle wheels corresponds. The output or control signal is fed to the modulation valve 24 via a conductor 32. at the lockout regulator described in the aforementioned US Pat. No. 3,515,440 is only an "On" - or "off" signal is generated and depending on this output signal the fluid pressure applied to the brake cylinders 12 is modulated by the modulation valve 24. According to the invention, the control unit 26 also takes on a control function by which the clutch 36 is one with a manually operated transmission 38 provided vehicle disengaged wi ^ d.

The clutch 36 lies between the motor 40 and the manually operated one Transmission 38 and contains a linkage 42, for example by depressing a not shown by the vehicle operator Foot pedal is adjusted to selectively engage and disengage clutch 36. A second linkage 44 lies between the linkage 42 and an actuating device 46 for disengaging the clutch, the actuating device 46 being activated by negative pressure or can be a hydraulically operated servomotor that actuates the clutch 36 upon energization of an electrically operated solenoid 48 moves out. Solenoid 48 can be energized via a conductor, not shown, connected to conductor 32,

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however, the clutch would then be in accordance with the pressure and -relief of the brake pressure can be applied and disengaged cyclically.

In order to prevent unnecessary engagement and disengagement of the clutch during a plurality of signals generated by the control unit 26 for cyclical actuation of the modulation valve 24, a locking stage 50 is provided. The locking stage is to the control unit 26 via a conductor 52 and to the solenoid. 48 connected via a conductor 54. The locking stage 50 can have a silicon-controlled rectifier, a relay or some other similar electrical component with a holding function and is brought into the conducting state by an output signal from the control unit 26; preferably the locking stage 50 includes a silicon controlled rectifier.

As shown most clearly in FIG. 2, the anode of the silicon-controlled Rectifier via conductor 58 to an electrical power source, such as the positive terminal of a battery 56. The solenoid 48 is on the one hand via the conductor 54 -to the Cathode of the silicon controlled rectifier and on the other hand connected to ground. The control gate of the silicon-controlled rectifier is at the output of the control unit 26. A reset switch 60 is located along conductor 58 and is dependent on the operation of the brake pedal

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open or closed, the switch 60 when depressed the brake pedals is closed and the power supply interrupted by the battery 56 when the brake pedal is released v / ird.

During operation, the silicon controlled rectifier prepared for the control state, v / when switch 60 is closed, i.e., the brake pedal 22 is depressed; then the silicon controlled rectifier is turned on via the Conductor 52 fed output signal of the control unit 26 in switched the control state. During a normal burn process, the switch 60 is disabled as a result of depressing the Brake pedal 22 is always closed, but the silicon-controlled rectifier is not in the conductive state because a Output signal from control unit 26 is missing. If a locking condition occurs or is imminent on the vehicle wheel or wheels, however, the silicon-controlled rectifier is switched over by a signal from the control unit 26 and gets into the conduction state, whereby the solenoid 48 is actuated and the The vehicle clutch is disengaged by the adjusting device 46. When the silicon controlled rectifier goes into the conducting state, it will remain in that state even if the signal disappears in the conductor 42 until the circuit is released by releasing the brake pedal 22 and thus by opening the switch 60 is opened. Thus, the locking stage 50 operates independently of the following, for the cyclical actuation of the

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Valve 24 voi'yS expensive unit 26 generated output signals and only as a function of the output signal generated first, so that the motor ■ remains uncoupled until the brake pedal is released. This process will be described in detail with reference to "ig explains; 3.

To provide a visual indication of a malfunction or failure To obtain the locking stage 50, a comparison device 62 is provided, which has one input 64 via a conductor 66 to the locking stage 50 and with its other input 68 via a conductor 70 to the electrical Conductor 52 is connected. A warning light 72 on the dashboard or another suitable location in the vehicle is via an electrical conductor 74 to the Comparison device 62 connected and grounded across the conductor. If the locking stage 50 is present an output signal generated by the control unit 26 is unable to get into the le.itz state, the vehicle driver becomes by the lighting up of the light 72 from the malfunction of the locking stage 50 and thus from the operational failure of the release device warned.

In Fig. 3 are the brake pressure, the output signal of the control unit and the release signal of the locking stage 50 plotted graphically over time. The curve "A" shows the Course of the brake fluid jerk for a conventional brake system,

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the brake actuation begins at time t and the brake fluid pressure increases to the maximum fluid pressure that can be achieved in the system. In certain roadway conditions, the application of the maximum brake pressure (or less) results in excessive slip and a blocking and / or slipping condition. If the vehicle wheels are locked or if there is excessive slip, the effectiveness of the braking system is impaired when the vehicle is stopped in a regulated manner. The braking pressure curve for braking the vehicle with a desired slip and thus utilizing the maximum coefficient of friction is shown by curve "B". The lock controller sets operating conditions that simulate the ideal brake pressure curve "B". The ideal curve ¹¹ B ″ changes as a function of the condition of the road surface; thus there is a family of ideal brake pressure curves for different types of road surface conditions. For the sake of simplicity, only a single curve of this type is shown.

The responsive to the output signals of the control unit 26 Modulation valve generates a modulated brake pressure curve "G". The curve "C" is preferably the ideal brake pressure curve "B" approximated and is essentially dependent on the inherent parameters of the modulation valve 24 (see the aforementioned US-Ps 5 515 440)

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The curve shows the output signal of the control unit 26 and the time dependency of the brake pressure curve "C" on the output signals "y". The curve "Z" shows the release signal generated by the locking stage 50 and the time dependency between the output signals y, y1 and j2 and the pressure curve "0".

Assuming that the brakes are applied at time t, the brake pressure increases along curve "A" until time t. at ¹ position O. "occurs a slipping state. As mentioned above, this state is sensed and the control unit 26 produces an output signal" y "for operating the modulating valve 24 and simultaneously for actuating the locking stage 50 by means of a from the control unit via the conductor 52 When the modulation valve 24 is actuated, the brake fluid pressure in the wheel brake cylinders 12 is reduced in the direction of point "c", while at the same time the locking stage 50 is now switched to the control state, as shown by Z ₁ on the curve "Z", thereby energizing the solenoid 48. As noted above, energizing the solenoid 48 actuates the actuator 46, thereby disengaging the vehicle engine 40 from the transmission 58. At one point along curve "d" to "e", this has changed Vehicle wheel turned up or speed gained, whereby the output signal "y" from the control unit 26

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"for example at time t _? , switched off and thus the initial actuation of the modulating valve 24 is interrupted. When this happens, the modulating valve 24 is able to quickly bring the fluid pressure back to the point" f ", which is close to the ideal curve ⁿ b", and then set a gradual pressure increase from point "f" to point "g" along a slightly inclined curve, the course of which essentially ^{corresponds to curve "B M.} During the change in brake fluid pressure from" d "to" e "and then after "g", the locking stage 50 remains in the control state, so that the motor 40 remains in the uncoupled state with respect to the manually operated gear 38. When the point "g" is reached, the transducer again detects a slipping state, so that the above-mentioned cycle " d "after" g "during the time period t 1 to t ^ essentially repeated. The control cycles are subsequently continued until the slipping or sliding state is over sore or the brake pedal is released by the vehicle driver, for example at time "t, -,". At this point in time (t "), the reset switch 60 is actuated as a result of the release of the brake pedal, and the vehicle again comes under the manual control of the vehicle driver. During an emergency braking or an imminent locking condition, the engine is prevented from coming to a standstill and the vehicle wheels can spin freely and pick up speed, since no braking effect from the stationary engine during a control cycle on the drive train or the vehicle (behind).

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wheels attacks. As mentioned above, about it In addition, a negative pressure to operate the modulation valve 24 is maintained and all servo devices are kept operational during the "lock control cycle". In addition, there is a sufficient source of power in the form of either negative pressure or hydraulic pressure to actuate the release actuator 46 available.

According to FIG. 4, a timer 61 can be used instead of the reset switch 60. For the sake of clarity, in FIG. 4 all components that correspond to the system according to FIG. 1 are provided with the same reference numerals with the addition of a comma. The timer stage 61 is excited and switched on by the output signal of the control unit 26 via a conductor 55 lying between the timer stage 61 and the conductor 52 '. As FIG. 3 shows, the time interval (Δ Τ) between corresponding output pulses t. If at least one average time interval is known between the occurrence of the cyclical output signals y to y1, etc., the timer stage is set so that the locking stage 50 is switched off after a period of time which is slightly longer than the period of time t .. to t ~. However, each time a new signal, "y *", is generated by the control unit 26 _{after a previous signal, "y" f, the time is of course}

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encoder level started again, so that the sequence of operations is repeated.

The reset switch 60 has been described in connection with the operation of the brake pedal 22, but the locking stage 50 can also be modified if desired so that they can be used in conjunction with the accelerator pedal or with the Switch works that actuates the rear brake lights during braking. In addition, the Locking stage can be modified in various ways and thereby adapted to other blocking regulators that have a different structure compared to the blocking regulator described.

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Claims (1)

Legal File: M-2377 Pat ent claims 1. j wheeled vehicle with fluid-actuated brakes, "" - a manually operated gearbox and a clutch by a release device (26,46,48,50) for the automatic release of the clutch (36) when stepping on a Radblockierzixstandes, which detects an occurring blocking condition and if it is present Signal device (26, 28, 30) generating output signals and one for at least one output signal appealing switching device (46 »48.50) for disengagement the coupling (36) contains. 2. Wheeled vehicle according to claim 1, characterized by a modulating valve responsive to the output signals (24) for the cyclical pressure reduction and regeneration of the fluid pressure supplied to the brakes (10, 12). 3. wheeled vehicle according to claim 1 or 2, characterized in that that the switching device has an actuating device (46,48) for disengaging the clutch (36) and a -18-309817 / 0 886 actuating device (46,48) for a length of each Duration of the output signal in the actuation position holding locking device (50) and thus the coupling (36) by the actuating device (46,48) can be retained in the disengaged position during several output signals. 4. Wheeled vehicle according to claim 3, characterized by a reset device (60,61) for releasing the locking device (60) and thus to re-engage the clutch (36). 5. wheeled vehicle according to claim 4 »characterized in that the resetting device is one of the brake pedal (22) actuated switch (60) is. 6. wheeled vehicle according to claim 4, characterized in that the resetting device is provided by at least one Output signal is switched on timer (61). 7. Wheeled vehicle according to one of claims 3 to 6, characterized by a comparison device (62) actuated by the locking device (50) to determine a Failure of the locking device (50). -19-309817 / 0886 8. Wheeled vehicle according to one of the preceding claims, characterized in that the signaling device (26, 28, 30) has a transducer (28, 30) for determining a occurring blocking condition and one with the measuring transducer contains coupled control unit (26) for generating electrical output signals. 9. wheeled vehicle with fluid-operated brakes,
a manually operated gearbox and a clutch as well as a lock controller, which detects a locking condition occurring on at least one vehicle wheel and signal means then producing an output signal and one responsive to the output signal Contains modulating valve for reducing the fluid pressure supplied to the brakes by a likewise responsive to the output signal Switching device (46, 48, 50) for uncoupling the vehicle engine (40). 10. Wheeled vehicle according to claim 9, characterized in that the switching device (46,48,50) contains: an adjusting device (44,46) coupled to the clutch (56),
an electrically operated valve (48) for actuating the actuating device and a locking stage (50) connected to the electrically operated valve (48) and switched to the conductive state by the output signal. -20-309817 / 0886 11. Wheeled vehicle according to claim 10, characterized by a manually operated switch (60) for switching the locking stage (50) in the non-conductive switching state. 12. Wheeled vehicle according to claim 10, characterized by a timer stage (61) for switching the locking stage (50) into the non-conductive switching state. 15. Wheeled vehicle or the like, with a manually operated gearbox, a clutch that can be actuated by a clutch pedal via a linkage and a lock controller for reducing the fluid pressure supplied to the brakes when a locking condition occurs at at least a vehicle wheel, characterized by an adjusting device (44146) coupled to the clutch (36) to disengage the clutch, a solenoid (48) for actuation the adjusting device (44,46) and one with the Blocking regulator (24,26,28,30) coupled switching stage (50, 52,54) 2 to switch the solenoid (48) on and off. 14. Wheeled vehicle according to claim 13, characterized in that the blocking regulator (24 / 26,28,? 0) is a control unit (26) for generating an output signal upon the occurrence of a Bloci ierzustandes ^r on at least one vehicle wheel 8AD O Rl Gi NAL,; -21- 3098 17/0886 contains and the switching stage. (50,52,54) with a responsive to the output signal, the solenoid (48) engaging Yerriegelungsstufe (50) is provided. 15. Wheeled vehicles according to claim 14, characterized by a fault indicator (62,72) which in the event of a failure the latching stage (50) responds and the Vehicle driver provides a malfunction display. 3098 177 08 0 6 ι L eer