Vehicle Line-Locking Braking System and Method

Abstract

The present disclosure relates to a computer-implemented method of line-locking a hydraulic vehicle braking system. The method includes performing a preliminary system check and controlling the distribution of fluid between a hydraulic module and two sets of vehicle brakes when the preliminary check is satisfied.

Description

TECHNICAL FIELD

The present disclosure relates to methods of line-locking hydraulic braking systems and braking systems for accomplishing the same.

BACKGROUND

Conventional vehicle braking systems include hydraulic and electric systems. Each system provides different performance characteristics. Generally speaking, hydraulic systems are more widely implemented and are less complex, less expensive braking systems. There are contemporary hydraulic systems that are supplemented with electronic components to provide anti-lock braking and traction control.

Some vehicles, e.g., “muscle cars,” manipulate a vehicle's braking system to improve tire traction at vehicle launch. To ensure maximum tire grip at take-off, a driver can conduct a “burn-out” in a water box to heat up the rear tires just prior to launch. With many conventional vehicles, in order to conduct a controlled burnout, a driver needs to manipulate the service brake system to allow the rear wheels to spin freely while the front brakes are applied. In some cases, the burn-out is achieved by the driver manipulating the throttle, brake and clutch. This is not a user-friendly delivery system, however, as it requires the driver to synchronize inputting various commands into the vehicle simultaneously. Moreover, if the vehicle is not in the best condition for burn-out, e.g., the wheels are slightly turned, it can be difficult for the driver to detect this.

Alternatively, a vehicle owner can install an aftermarket system that will allow the driver to keep the front brakes applied while the rear brakes are released; after the driver releases the brake pedal a much more controlled burn-out can be accomplished. Such aftermarket systems are inferior to a system incorporated with original vehicle equipment for various reasons. For example, aftermarket systems can have reliability issues, are usually purely mechanical systems having no electric or automated controls which can also be less user-friendly, they are not repeatable and they do not perform preferred preliminary system checks that can increase the performance of the braking system before, during and/or after burn-out.

There are completely electric braking systems that can be incorporated into the vehicle which control the distribution of power between the front and rear braking systems. For example, U.S. Patent Application No. 2008/0015761 titled “Electric Braking Device for Vehicles” discloses a purely electric braking system that includes an on-board computer and control module which controls the power supply to the braking modules. Since this system utilizes electric brakes the system is more complex and more expensive than systems having hydraulic brakes. Moreover, the control logic disclosed in the '761 Application is not tailored to a line-locking function but is tailored toward mitigating detected degradations in the operating modes of the brakes to reduce the overall power consumption of a vehicle. The disclosed braking device would not accommodate a vehicle line-locking braking system.

Therefore, it is desirable to have a method of line-locking a hydraulic vehicle braking system and a braking system for accomplishing the same that is more user-friendly. It is further desirable to have a system that performs preliminary system checks to improve vehicle performance before, during and/or after burn-out. A feature is needed that will utilize the original vehicle equipment to provide a burn-out feature that is controlled and repeatable for the driver without the need of adding any additional content.

SUMMARY

The present invention may address one or more of the above-mentioned issues. Other features and/or advantages may become apparent from the description which follows.

Certain embodiments of the present invention include a computer-implemented method of line-locking a hydraulic vehicle braking system. The method includes the steps of receiving an electric signal through a user interface to a control module; performing a preliminary system check; and controlling the distribution of fluid between a hydraulic module and two sets of vehicle brakes when the preliminary check is satisfied.

Another exemplary embodiment of the present invention include a vehicle braking system, having: a first hydraulic brake module; a second hydraulic brake module; a hydraulic module configured to provide fluid to the first and second brake modules; a valve system between the hydraulic module and the first and second brake modules, configured to disconnect the hydraulic module from the first and/or second set of hydraulic brake modules; and an electric control module configured to control the valve system.

Another exemplary embodiment of the present invention involves a vehicle configured to line-lock. The vehicle includes: a user interface; an electric control module linked to the user interface and configured to receive a signal from the user interface for activation of a line-locking mode of operation; a first hydraulic brake; a second hydraulic brake; a hydraulic module configured to provide fluid to the first and second brakes; and a valve system between the hydraulic module and the first and second brakes, configured to disconnect the hydraulic module from the first and/or second set of hydraulic brakes. The control module is configured to control the valve system.

The present teachings provide a method that will allow the driver to apply the vehicle brake system in such a manner to allow a controlled burn-out utilizing the vehicles electronically controlled hydraulic brake system.

One advantage of the disclosed burn-out or line-locking feature is that it utilizes standard equipment already found on vehicles. There is no need for an owner to purchase an aftermarket add-on system.

The disclosed line-locking feature utilizes failsafe criteria so that the system can only be activated in a controlled manner. Moreover, the disclosed features constantly monitor key vehicle parameters and conditions once activated to ensure the driver maintains control and mechanical/electronic malfunctions are accounted for.

Another advantage of the disclosed teachings is that they enable original equipment manufactures to coupe additional revenue by providing a feature that customers currently purchase from aftermarket suppliers. Customers also enjoy additional benefits as a factory warranty can apply to the line-locking braking features.

Yet another advantage of the disclosed braking systems is that they can be incorporated into the vehicle providing a user or driver interface. The interface is integrated into the vehicle versus having to make modifications to the vehicle for aftermarket systems.

An additional advantage to the disclosed line locking system is that it is based on electronic control which provides very repeatable and controlled burn-outs versus an add-on system that can have significant variability.

In the following description, certain aspects and embodiments will become evident. It should be understood that the invention, in its broadest sense, could be practiced without having one or more features of these aspects and embodiments. It should be understood that these aspects and embodiments are merely exemplary and explanatory and are not restrictive of the invention.

The invention will be explained in greater detail below by way of example with reference to the figures, in which the same references numbers are used in the figures for identical or essentially identical elements. The above features and advantages and other features and advantages of the present invention are readily apparent from the following detailed description of the best modes for carrying out the invention when taken in connection with the accompanying drawings. In the figures:

BRIEF DESCRIPTION OF THE DRAWINGS

FIG. 1 is a rear view of a vehicle with a braking system according to an exemplary embodiment of the present invention.

FIG. 2 is a perspective view of a center mounted console having a user message center compatible with the vehicle shown in FIG. 1.

FIG. 3 is schematic illustration of a vehicle braking system compatible with the vehicle shown in FIG. 1.

FIG. 4 is a schematic illustration of a control module compatible with the vehicle braking system of FIG. 3.

FIG. 5 illustrates an algorithm for controlling a vehicle braking system and user message center.

Although the following detailed description makes reference to illustrative embodiments, many alternatives, modifications, and variations thereof will be apparent to those skilled in the art. Accordingly, it is intended that the claimed subject matter be viewed broadly.

DETAILED DESCRIPTION

Referring to the drawings, FIGS. 1-5, wherein like characters represent the same or corresponding parts throughout the several views there are shown exemplary vehicle line locking braking systems and methods pertaining to the use of the same. The disclosed braking systems can be used in various types of vehicles including for example small/large cars, coupes, sedans, convertibles, trucks, vans, minivans and SUVs. In some embodiments, the braking systems include hydraulic brake modules that are governed by an electric control module.

The present teachings provide a method that will allow the driver to apply the vehicle's brake system in a manner to allow a controlled burn-out, utilizing the vehicles electronically controlled hydraulic brake system. In the illustrated exemplary embodiments, a vehicle electronic brake system includes an electronic module which is attached to a hydraulic brake valve block. Each individual wheel braking circuit is controlled via the electronic module and manipulated by the hydraulic valve block. The electronic module has the capability to provide brake pressure, remove brake pressure and hold brake pressure to individual wheels.

Referring now to FIG. 1, there is shown therein a rear view of a vehicle 10 configured with a braking system according to an exemplary embodiment of the present invention. The vehicle 10 has a vehicle cabin 20 where the operator or driver is seated. The vehicle cabin 20 includes controls that the driver can utilize to enable the line-locking feature for the braking system. The shown vehicle 10 is capable of achieving an expedited launch with the use of an exemplary braking system without the addition of aftermarket vehicle systems.

The shown vehicle 10 has a braking system that includes hydraulic braking modules that are linked to a valve system (as discussed with respect to FIGS. 3-4). A valve system is controlled by an electric control module. The driver controls activation and de-activation of each braking module via an electronic control module (e.g., 330 as discussed with respect to FIG. 3). In the shown embodiments, the electric control module includes system check logic that can be indicative of various vehicle conditions. To enable the line-locking feature for the braking system, the driver first selects this mode of control via a vehicle selection menu in the message center (e.g., 130 as shown in and discussed with respect to FIG. 2). Once selected, the driver will apply the service brakes to a pre-defined pressure. When the brake pressure is achieved, the brake electronic module will isolate the vehicle's front brake module(s) or circuit(s) from the driver via the hydraulic brake control valves or valve systems and the pressure will be locked and communicated to the driver. At that point the driver can remove pressure from the brake pedal and the front brakes will remain applied. The driver can then apply throttle and initiate a burn-out or burning rubber on the rear wheels 30, creating tire smoke 40 as shown in FIG. 1.

The vehicle includes a message center 50 with a user interface 60 for the driver, as shown in FIG. 2. The user interface 60 can be incorporated into the vehicle instrument panel 70 or instrument cluster. The interface 60 can be included in a center console (e.g., 80) or other locations in the vehicle interior as well. An electric control module is linked to the user interface 60 and configured to receive a signal from the user interface for activation or deactivation of a line-locking mode of operation. Control module can be hardwired or in wireless communication with the user interface 60.

User interface 60, shown in FIG. 2, is configured to provide a user with audio and/or visual indicators of braking system and vehicle conditions. The electric control module comprises system check logic configured to assess at least one vehicle condition and control the valve system according to the vehicle condition. The shown interface 60 includes a touch screen with “soft keys” 90 and 100 to receive user input. The user interface 60 can also receive driver inputs with respect to control of the braking system. For example, in the shown embodiment, the user interface is configured with a start command key 90 that instructs the control module to start from the beginning of the operating sequence for the line-locking feature of the braking system. The user interface also includes a cancel command key 100 configured to cancel the line lock selection. Where the driver has initiated the starting sequence of the line-locking feature, the sequence can be interrupted. The user interface also includes a message center configured to deliver system information to a vehicle user.

User interface 60 is configured to receive and output audio commands as well. User interface 60 includes a microphone linked to the control module. Control module is configured with voice recognition software. User interface 60 is configured to, for example, restart the operating sequence for line locking upon receiving a “reset” audio command. The user interface 60 is also configured to abandon the line-locking braking sequence by receiving the escape command. The “escape” audio command interrupts the operating sequence of the control module when the braking system is operating in line-locking mode.

In the embodiment illustrated in FIG. 2, the user interface 60 includes a message center 130 configured to audibly deliver system information to a vehicle user. For example, where the system has abandoned the line-locking operating sequence the user interface 60 can send a text or audible message of “system abort” to the driver. Any number of messages or commands can be programmed into the control module for execution.

Referring now to FIG. 3, there is shown therein a vehicle braking system 200 according to an exemplary embodiment of the present invention. The braking system 200 is designed for use with a four-wheel vehicle, for example, as shown in FIG. 1. The braking system in FIG. 3 is attached to a vehicle chassis having four wheels 210. At each wheel a braking module 220, 230, 240 and 250 is dedicated to selectively apply braking pressure against the wheel. Braking modules 220, 230, 240 and 250 are hydraulic braking modules. Braking modules 220, 230, 240 and 250 can be, for example, disc brakes, drum brakes or electric brakes. Hydraulic fluid is supplied to the braking modules 220, 230, 240 and 250 via hydraulic modules (or cylinders) 260, 270. Hydraulic module 260 provides fluid to braking modules 220 and 230. Hydraulic module 270 supplies fluid to braking modules 240 and 250.

A valve system 280 is positioned between the hydraulic modules 260, 270 and the brake modules 220, 230 and 240, 250 respectively as shown in FIG. 3. The illustrated valve system 280 includes four valves 290, 300, 310 and 320 that control the distribution of fluid from the hydraulic modules to each brake modules. Valve system 280 is configured to selectively, at least partially disconnect the hydraulic modules from the brake modules. In the shown embodiment, valve 290 controls the distribution of fluid between hydraulic module 260 and brake module 220. Valve 300 controls the distribution of fluid between hydraulic module 260 and brake module 230. Valve 310 controls the distribution of fluid between hydraulic module 270 and brake module 240. Valve 320 controls the distribution of fluid between hydraulic module 270 and brake module 250. In this way brakes can be selectively turned on and off on any individual wheel or set of wheels.

An electric control module 330 is also included in the braking system 200 shown in FIG. 3. Control module 330 is configured to control the valve system 280. Control module 330 is linked to valves 290, 300, 310 and 320. Control module 330 can be hard-wired or wirelessly connected to the valves. In one embodiment, valves 290, 300, 310 and 320 include solenoids and are actuated upon receiving an electric control signal from the control module 330. Control module 330 includes a microprocessor (e.g., 350 as shown in FIG. 4) configured to execute predetermined commands and receive commands from a user interface.

The electric control module 330 is linked to a user interface 60, for example, as shown in FIG. 2. Control module 330 is configured to receive signals from the user interface 60. Signals can be indicators of vehicle conditions or commands for the control module 330. The electric control module 330 includes system check logic configured to assess whether a predetermined user command is entered into the user interface. Control module 330 is responsive to various user commands, such as, e.g., a reset command, escape command or a break in the ignition key cycle.

Referring now to FIG. 4, there is shown therein the control module 330 with other braking system components. Control module 330 is configured to at least control a valve system 280 that governs the distribution of fluid between a first set of brakes 340 and a second set of brakes 350. Control module 330 is linked to various vehicle systems through sensors configured to take measurements of vehicle performance characteristics and user inputs. In the shown embodiment, control module 330 is linked to a user interface 360. User interface 360 enables the vehicle driver to send information to the control module 330 and enable the control module to relay information to the driver.

As shown in FIG. 4, the electric control module 330 includes system check logic 370 configured to assess vehicle speed. Control module 330 is linked to the vehicle odometer 380. The control module 330 is configured to at least partially turn the valve system off when the vehicle speed exceeds a predetermined amount.

The system check logic 370 is configured to assess whether a predetermined time limit has been exceeded. A timer 390 is linked to the control module 330. Initiating the operating sequence for the line-locking braking feature starts the timer 390. The control module 330 is configured to at least partially turn the valve system 280 off when the predetermined time limit has been exceeded. In one embodiment, the timer 390 is set to 30 seconds from activation of the line locking system. In another exemplary embodiment, the timer 390 is set to 180 seconds from activation of the line locking system.

The system check logic 370 is configured to assess a steering wheel position. The steering wheel column includes a position sensor 400 in communication with control module 330. In one embodiment, the control module 330 is configured to at least partially turn the valve system 280 off when the steering wheel position is less than or greater than a predetermined angular range. For example, if the steering wheel is turned more than 3 degrees from a longitudinal axis of the vehicle the control module can abort the line-locking operating sequence and deactivate the valve on the rear brakes 350.

The system check logic 370, as shown in FIG. 4, is configured to assess whether a vehicle traction control system 410 is inactive. The vehicle traction control system 410 is configured to control the vehicle's antilock braking system and other all-weather control features. In one embodiment, the traction control system 410 is configured to reduce tire slip. The control module 330 is configured to at least partially turn the valve system 280 off when the traction control system 410 is active. The electronic module 330 combined with the hydraulic valve system 280 is designed to perform vehicle stability control functions such as traction control and yaw control.

Any number of sensors can be linked to the control module 330 for use with the line locking braking system 200. “X_Sensor” 420 is a sensor representing any number of exemplary sensors that can be included in the system 200. For example, in the shown embodiment the vehicle braking system 200 includes system check logic 370 configured to assess whether a vehicle service brake is applied. A sensor, such as X_Sensor 420, is included in the transmission to determine if the service brake or park pawl is applied. The control module 330 is configured to at least partially turn the valve system 280 off when the vehicle service brake is applied. Other sensors, such as brake fluid viscosity sensors, wheel speed sensors, brake fluid level monitors and other devices can be utilized with the line locking braking system 200.

Though the links shown between system components are described in terms of hardwired connections, any one of the components can be wirelessly linked to the control module. Bluetooth technology, configured to enable short-range communication between electronic devices, is utilized to enable the components to communicate with the control module wirelessly. Other wireless standards or technologies can be used with the braking system such as infrared systems, RF systems, IEEE standard 802.11 and other communications platforms.

Referring now to FIG. 5, there is illustrated therein an algorithm 500 for controlling a vehicle braking system and user message center. The illustrated algorithm 500 can be executed by a processor circuit incorporated into a control module, e.g., system check logic 370 as shown in FIG. 4. System commands can be inputted into the control module via a user interface, e.g., 60 as shown in FIG. 2. User interface 60 sends electric signals to a control module or computer to execute the steps of the algorithm 500. The control module implements the line locking algorithm 500 by controlling the distribution of fluid between a hydraulic module and two sets of vehicle brakes or brake modules.

At step 510, as shown in FIG. 5, the line-locking mode of operation is initiated. Driver enters information indicative of a desire to utilize the vehicle line lock feature. At step 520 the control module checks the vehicle speed. If the speed is not equal to a predetermined amount valves to the rear brake modules are turned off and the braking system is unable to operate the line locking feature (step 530). In this embodiment, the system is disabled if the vehicle speed is not equal to zero. The driver is unable to select the line lock from the message center. In the illustrated algorithm, if the speed is equal to zero the driver can select line lock from the vehicle message center (step 540). At this point in the operating sequence the message text center can either display that the line lock is “on” or “off” as shown at step 550.

At step 560 as shown in FIG. 5, the vehicle line lock feature is enabled but not fully active. The message center displays a message to the driver indicating “line lock available” (step 570). Thereafter, the system enters into two preliminary system checks. In each series of system checks the algorithm monitors the time elapsed since activation of the line locking feature. At steps 580 and 590 the system checks a timer to determine if a predetermined time maximum has been exceeded. If the time limit is exceeded valves to the rear braking modules are turned off and the line lock feature is cancelled (step 600). A signal is sent to the message center indicating that the line lock is off 610.

Algorithm also checks the vehicle speed at steps 620 and 630. At step 630 the control module checks the vehicle odometer. If the vehicle speed is in excess of a predetermined amount the line lock feature is cancelled and the system proceeds to step 600. A signal is sent to the message center indicating that the line lock is off 610. If the vehicle speed is zero the operating sequence continues to another system check. At step 640 the control module checks to see whether a predetermined user command is received; the module checks to see if the ignition key has been cycled. If the ignition has been cycled valves to the rear braking modules are turned off and the line lock feature is cancelled 600. A signal is sent to the message center indicating that the line lock is off 610.

At step 650, as shown in FIG. 5, the system checks if the service brakes are applied. If the service brake is applied valves to the rear braking modules are turned off and the line locking operating system is cancelled 600. At step 660 the system checks the steering wheel to ensure that it is properly inline. If the steering wheel is posited less than or greater than a predetermined angular range valves to the rear braking modules are turned off and the line lock feature is cancelled 600. At step 670 the system checks to see if the vehicle traction control system is inactive. If the traction control system is active valves to the rear braking modules are turned off and the line lock feature is cancelled 600.

To activate the line locking feature the driver presses the escape switch as shown at step 680 in FIG. 5. The hydraulic module is disconnected from the rear set of brake modules. Pressing escape releases the valve on the rear braking modules. The rear wheels are able to move freely while the front brakes stay active. Burn out can be initiated and line lock is active (step 690). Control module sends a notification to the message center indicating that the line lock is engaged (step 700). If the driver hits the escape key a second time, as shown in step 710, the system exits the line locking operating mode. The line lock feature is cancelled 600. A signal is sent to the message center indicating that the line lock is off 610.

Control module can be configured to include a greater or fewer number of preliminary system checks before activating the line locking feature. The exemplary preliminary system checks are designed to improve the performance of the vehicle before, during or after launch. Other preliminary system checks can be programmed into the control module or added to the braking system and be within the scope of the present invention.

It will be apparent to those skilled in the art that various modifications and variations can be made to the methodologies of the present invention without departing from the scope its teachings. Other embodiments of the invention will be apparent to those skilled in the art from consideration of the specification and practice of the teachings disclosed herein. It is intended that the specification and examples be considered as exemplary only.

While the best modes for carrying out the invention have been described in detail, those familiar with the art to which this invention relates will recognize various alternative designs and embodiments for practicing the invention within the scope of the appended claims.

Claims

1. A computer-implemented method of line-locking a hydraulic vehicle braking system, comprising:

receiving an electric signal through a user interface to a control module;

performing a preliminary system check; and

controlling the distribution of fluid between a hydraulic module and two sets of vehicle brakes when the preliminary check is satisfied.

2. The method of claim 1, wherein performing a preliminary system check includes assessing the vehicle speed.

3. The method of claim 1, wherein performing a preliminary system check includes assessing whether a predetermined time limit has been exceeded.

4. The method of claim 1, wherein performing a preliminary system check includes assessing a steering wheel position.

5. The method of claim 1, wherein performing a preliminary system check includes assessing whether a vehicle traction control system is inactive.

6. The method of claim 1, wherein performing a preliminary system check includes assessing whether a predetermined user command is received.

7. The method of claim 1, wherein performing a preliminary system check includes assessing whether a vehicle service brake is applied.

8. The method of claim 1, wherein the controlling the distribution of fluid includes disconnecting the hydraulic module from the first and/or second set of hydraulic brakes.

9. A vehicle braking system, comprising:

a first hydraulic brake module;

a second hydraulic brake module;

a hydraulic module configured to provide fluid to the first and second brake modules;

a valve system between the hydraulic module and the first and second brake modules, configured to disconnect the hydraulic module from the first and/or second set of hydraulic brake modules; and

an electric control module configured to control the valve system.

10. The braking system of claim 9, wherein the electric control module is linked to a user interface, configured to receive a signal from the user interface; and

wherein the electric control module comprises system check logic configured to assess whether a predetermined user command is entered into the user interface.

11. The braking system of claim 9, wherein the predetermined user command is a reset command, escape command or break in ignition key cycle.

12. The braking system of claim 9, wherein the electric control module comprises system check logic configured to assess the vehicle speed; and

wherein the control module is configured to at least partially turn the valve system off when the vehicle speed exceeds a predetermined amount.

13. The braking system of claim 9, wherein the electric control module comprises system check logic configured to assess whether a predetermined time limit has been exceeded; and

wherein the control module is configured to at least partially turn the valve system off when the predetermined time limit has been exceeded.

14. The braking system of claim 9, wherein the electric control module comprises system check logic configured to assess a steering wheel position; and

wherein the control module is configured to at least partially turn the valve system off when the steering wheel position is less than or greater than a predetermined angular range.

15. The braking system of claim 9, wherein the electric control module comprises system check logic configured to assess whether a vehicle traction control system is inactive; and

wherein the control module is configured to at least partially turn the valve system off when the traction control system is active.

16. The braking system of claim 9, wherein the electric control module comprises system check logic configured to assess whether a vehicle service brake is applied; and

wherein the control module is configured to at least partially turn the valve system off when the vehicle service brake is applied.

17. A vehicle configured to line-lock, the vehicle comprising:

a user interface;

an electric control module linked to the user interface and configured to receive a signal from the user interface for activation of a line-locking mode of operation;

a first hydraulic brake;

a second hydraulic brake;

a hydraulic module configured to provide fluid to the first and second brakes; and

a valve system between the hydraulic module and the first and second brakes, configured to disconnect the hydraulic module from the first and/or second set of hydraulic brakes;

wherein the control module is configured to control the valve system.

18. The vehicle of claim 17, wherein the user interface is incorporated into an instrument panel in the vehicle interior.

19. The vehicle of claim 18, wherein the user interface includes a cancel command key configured to re-start the control module.

20. The vehicle of claim 18, wherein the user interface includes a message center configured to deliver system information to a vehicle user.

21. The vehicle of claim 18, wherein the electric control module comprises system check logic configured to assess at least one vehicle condition and control the valve system according to the vehicle condition.