Fault-tolerant brake system with two-wheel manual push-over

Abstract

The invention discloses a fault-tolerant brake system with two wheel manual push-over. A fault tolerant brake system includes a two-wheel manual push-through device for selectively actuating first and second pairs of wheel brakes. The master cylinder is selectively operable during the manual push-through mode by actuation of the brake pedal to generate brake actuation pressure to the at least one MC output for actuating the first pair of wheel brakes. A single action plunger ("SAP") is operable during a normal non-fail braking mode to generate brake actuation pressures at the first SAP output and the second SAP output for hydraulically actuating the first and second pairs of wheel brakes, respectively. A two-position three-way valve ("2P3W valve") is hydraulically connected with the MC output, the first SAP output, and the first pair of wheel brakes. A 2P3W valve places the front wheel brake pair in fluid communication with the SAP in a normal non-fail braking mode and in fluid communication with the master cylinder in a manual push-over braking mode.

Description

Technical Field

[0001] This disclosure relates to apparatus and methods for fault-tolerant braking systems, and more specifically, to methods and apparatus for fault-tolerant braking systems having two wheels manually pushed over. Background Technology

[0002] This invention generally relates to vehicle braking systems. Vehicles typically utilize hydraulic braking systems for deceleration and stopping. These systems vary in complexity, but a basic braking system generally includes a brake pedal, a master cylinder, fluid conduits that can be arranged in two similar but independent brake circuits, and wheel brakes in each circuit. The vehicle driver operates the brake pedal, which is directly or indirectly connected to the master cylinder. When the brake pedal is depressed, the master cylinder generates hydraulic pressure in both brake circuits by pressurizing brake fluid. The pressurized fluid flows through the fluid conduits in both circuits to actuate the brake cylinders at the wheels, thereby decelerating the vehicle. The basic braking system typically uses a brake booster that provides force to the master cylinder to assist the pedal force created by the driver. The force from the booster assists the pedal force acting on the piston of the master cylinder, generating pressurized fluid in conduits that are in fluid communication with the wheel brakes.

[0003] In assisted mode, during the initial movement of the brake pedal unit, the driver depresses the brake pedal, causing an initial movement of the input piston in the master cylinder. Further movement of the input piston pressurizes the input chamber of the master cylinder, causing fluid to flow into the pedal simulator. As the fluid diverts into the pedal simulator, the simulated pressure chamber within the simulator expands, causing movement of the piston within the simulator. This piston movement compresses the spring assembly housed within the pedal simulator and biases the piston, thereby providing a feedback force to the driver via the brake pedal. This feedback force simulates the force a driver feels at the brake pedal in a conventional vacuum-assisted hydraulic brake system, thus providing a predictable and comfortable "brake feel" for the driver.

[0004] Descriptions of prior art braking systems can be found in U.S. Patent No. 10,730,501, entitled "Vehicle Brake System with Auxiliary Pressure Source," granted to Blaise Ganzel on August 4, 2020; U.S. Patent Application Publication No. 1260 / 0307538, entitled "Brake System with Multiple Pressure Sources," published by Blaise Ganzel on October 1, 2020; and U.S. Patent Application Serial No. 17 / 400,250, entitled "Apparatus and Method for Control of a Hydraulic Brake System Including Manual Pushthrough," filed by Blaise Ganzel on August 12, 2021, all of which are incorporated herein by reference in their entirety for all purposes. Summary of the Invention

[0005] In one aspect, alone or in combination with any other aspect, a fault-tolerant braking system is provided, comprising a two-wheel manual push-over device for selectively actuating first and second pair wheel brakes. The system includes a reservoir and a master cylinder operable to provide a brake signal in response to actuation of a brake pedal connected thereto. The master cylinder is selectively operable during manual push-over mode by actuation of the brake pedal to generate brake actuation pressure at at least one MC output for hydraulically actuating the first pair of wheel brakes. A single-acting plunger (“SAP”) is operable during normal, fault-free braking mode by actuation of an electric SAP motor to generate brake actuation pressures at a first SAP output and a second SAP output, respectively, for hydraulically actuating the first and second pair of wheel brakes. A two-position three-way valve (“2P3W valve”) is hydraulically connected to the MC output, the first SAP output, and the first pair of wheel brakes. The 2P3W valve selectively controls the flow of hydraulic fluid from a selected one of the master cylinder and SAP to the 2P3W valve output hydraulically connected to the first pair of wheel brakes. An auxiliary power transmission unit (“PTU”, also known as an “auxiliary brake module”) is configured to selectively provide pressurized hydraulic fluid at the first and second PTU outputs to actuate the first and second pairs of wheel brakes in at least one of a normal non-failure braking mode and a standby braking mode. The auxiliary power transmission unit includes an electric PTU motor configured to selectively pressurize the hydraulic fluid by transmitting rotational motion to at least two pump pistons, each pump piston providing pressurized hydraulic fluid to a corresponding one of the first and second PTU outputs. Each of the first and second PTU outputs provides fluid to a corresponding pair of the first and second pair of wheel brakes. The electronic control unit (“ECU”) selectively controls at least one of the SAP, the auxiliary power transmission unit, and the 2P3W valve in response to a brake signal. The auxiliary power transmission unit and the SAP are fluidly connected to a reservoir. The 2P3W valve places the first pair of wheel brakes in fluid communication with the SAP in normal, non-faulty braking mode and in fluid communication with the master cylinder in manual push-over braking mode. Attached Figure Description

[0006] For a better understanding, please refer to the attached diagram, in which:

[0007] Figure 1 This is a schematic hydraulic diagram of an example brake system with a first example configuration according to one aspect of the present invention; and

[0008] Figure 2 yes Figure 1 A schematic hydraulic diagram of a second example configuration of the example brake system. Detailed Implementation

[0009] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this disclosure pertains.

[0010] The present invention comprises, consists of, or is substantially composed of the following features in any combination of the following features.

[0011] Figure 1 A first configuration option of an example fault-tolerant braking system 100 is schematically depicted, including two-wheel push-through devices for selectively actuating multiple wheel brakes 102, such as a first pair and a second pair of wheel brakes 102. The braking system 100 is shown here as a hydraulic braking system, wherein braking force is applied to the braking system 100 using fluid pressure. The braking system 100 can be suitably used for ground vehicles, such as motor vehicles with four wheels, each associated with a wheel brake. Furthermore, the braking system 100 can be equipped with other braking functions, such as anti-lock braking (ABS) and other slip control features, to effectively brake the vehicle. Components of the braking system 100 can be housed in one or more blocks or housings. These blocks or housings can be made of solid materials, such as aluminum, which are drilled, machined, or otherwise shaped to house the various components. Fluid conduits can also be formed within the blocks or housings.

[0012] exist Figure 1 In the embodiment of the brake system 100 shown, there are four wheel brakes 102, each of which can have any suitable wheel brake configuration that operates electrically and / or by applying pressurized brake fluid. Each of the wheel brakes 102 may include, for example, a brake caliper mounted on a vehicle, for engaging with a friction element (e.g., a brake disc) that rotates with the wheel, thereby achieving braking of the associated wheel. The wheel brakes 102 can be associated with any combination of the front and rear wheels of a vehicle on which the corresponding brake system 100 is installed. For example, the brake system 100 may be configured as a vertically split or diagonally split system. For ease of description, the wheel brakes 102 are referred to herein as paired wheel brakes 102, each pair including a front wheel brake and a rear wheel brake. However, this description does not limit the configuration, control, position, and / or type of the wheel brakes 102 provided; those skilled in the art can readily provide suitable braking devices for specific usage environments.

[0013] like Figure 1As schematically shown, the braking system 100 includes a master cylinder 104 having a housing that defines a longitudinally extending bore for slidably receiving various cylindrical pistons and other components therein. As illustrated, the master cylinder 104 may be of a single-chamber type.

[0014] Brake pedal 106 is operatively connected to master cylinder 104, and is actuated by the driver when the driver depresses it. Brake travel sensors 108 (two are shown for redundancy) are configured to provide a brake signal to other parts of the braking system 100, indicating the depressing of brake pedal 106 (binary on / off, and / or containing some quantitative information related to the depressing of brake pedal 106). That is, master cylinder 104 is operable to provide a brake signal in response to actuation of brake pedal 106 to which it is connected. The brake signal can be utilized by one or more other components of the braking system 100 to achieve desired braking of the motor vehicle, for example, when the braking system 100 is in a normal, non-faulty braking mode, via the transmission of electronic signals.

[0015] The associated structures of the brake pedal 106 and master cylinder 104 can also serve as a backup pressurized fluid source to substantially replace the normal supply of pressurized fluid from the auxiliary power transmission unit in certain failure conditions of the brake system 100 and / or during the initial activation of the brake system 100. This situation is referred to as a manual push-over event, or “manual application,” and can be accomplished in conjunction with the actuation of any available backup pressurized fluid source, or independently. During the manual push-over mode, the master cylinder 104 can be selectively operated by actuation of the brake pedal 106 to generate brake actuation pressure to at least one MC output 110, thereby hydraulically actuating at least one wheel brake 102 of the brake system 100.

[0016] In this manual push-over mode, master cylinder 104 can supply pressurized fluid to MC output 110, and then route the pressurized fluid to one or more pairs of hydraulically operated wheel brakes 102 as needed. This flow is primarily pushed through master cylinder 104 by the mechanical pressure applied by the driver's foot to the brake pedal 106. That is, during manual push-over mode, master cylinder 104 can be selectively operated by actuation of the brake pedal 106 connected to it to generate brake actuation pressure for hydraulically actuating at least one pair of wheel brakes. (For...) Figure 1 For ease of description, the following assumes that the pair of front wheel brakes 102 are hydraulically actuated brakes in the manual push-over mode of the vertical split system.

[0017] The braking system 100 typically also includes a single-acting plunger-type pressurized fluid source (shown generally at 112) and a fluid reservoir 114. The reservoir 114 stores and holds the hydraulic fluid used in the braking system 100. The fluid within the reservoir 114 is preferably maintained at or near atmospheric pressure, but may also be stored at other pressures as needed. The reservoir 114 is schematically shown with two tanks or sections connected to two fluid lines. These sections may be separated by one or more internal walls within the reservoir 114 and are provided to prevent the reservoir 114 from being completely emptied in the event that one section is depleted due to a leak via one of the two lines connected to the reservoir 114. Alternatively, the reservoir 114 may comprise multiple separate housings. The reservoir 114 may include at least one level sensor 116 for detecting the level of one or more sections of the reservoir 114.

[0018] The single-acting plunger 112 (“SAP”) of the braking system 100 acts as a pressure source to provide the desired brake fluid pressure level to the wheel brakes 102 during at least one of a typical or normal non-failure braking mode and a standby braking mode. After any desired type of braking is applied, fluid from the wheel brakes 102 can return to the single-acting plunger 112 and / or be diverted to the reservoir 114. In the illustrated embodiment, the single-acting plunger 112 is configured to selectively provide pressurized hydraulic fluid to a first SAP output 118 and a second SAP output 120 to hydraulically actuate the corresponding first and second pairs of wheel brakes 102 in at least one of a normal non-failure braking mode and a standby braking mode. The single-acting plunger 112 includes a first electric SAP motor 122.

[0019] SAP sensor 124 may be provided to help determine the rotational state (direction, amplitude, speed or any other quantity) of the first electric motor 122, for use by any other component of the brake system 100 for calculation and / or control as needed.

[0020] After the brakes are applied, fluid from wheel brake 102 can return to master cylinder 104, single-acting plunger 112, and / or be diverted to reservoir 114. Other configurations of the brake system 100 (not shown) are also conceivable, including hydraulic control of only one(s) wheel brake(s) (with other wheel brakes electrically controlled / actuated). Following various aspects of the invention, those skilled in the art can readily provide such a device for the desired application environment.

[0021] The pedal simulator 126 may be selectively fluidly connected to the master cylinder 104 to provide the driver with a predetermined brake pedal 106 response (e.g., brake pedal "feel"). The brake system 100 may also include an optional solenoid-actuated pedal simulator valve 128, which is electronically controllable between a closed position and an electrically disconnected position, and fluidly located between the reservoir 114 and the master cylinder 104. The pedal simulator valve 128 may be controlled during various test modes to determine the proper operation of other components of the brake system 100. For example, the pedal simulator valve 128 may be actuated to the disconnected position to determine whether seals of various components of the brake system 100 (e.g., the piston seal of the pedal simulator 126) are leaking. The pedal simulator valve 128 itself may perform a leak test when de-energized (e.g., through feedback from other components of the brake system 100).

[0022] A pressure switch 130 may be provided for leak detection in the pedal simulator valve 128, and this pressure switch, similar to the pedal simulator valve 128, is fluidly located between the reservoir 114 and the master cylinder 104. The pressure switch 130 selectively provides a pressure sensor signal to the electronic control unit. The pressure sensor signal from the pressure switch 130 indicates the operating condition of the pedal simulator valve 128, such as whether the pedal simulator valve 128 is functioning properly, whether it is blocked, whether it cannot be disconnected, or whether it has any other operating condition that can be transmitted to the electronic control unit. The pressure switch 130 also allows detection of a blocked or faulty condition in the pedal simulator valve 128; if the pedal simulator valve 128 is found to be inoperable, the system can be put into a manual push-through standby operating mode using other components of the brake system 100. Additionally, as Figure 1 As schematically shown, a shut-off port 132 can be provided to the master cylinder 104, which has an orifice that can detect significant / serious leaks in the pedal simulator valve 128.

[0023] A two-position three-way valve (“2P3W valve”) 134 is hydraulically connected to the MC output 110, the first SAP output 118, and the first pair of wheel brakes 102. (In the figures, for ease of description, the leftmost pair of wheel brakes 102 is considered the “first” pair of wheel brakes 102, and the rightmost pair of wheel brakes 102 is considered the “second” pair of wheel brakes.) The 2P3W valve 134 selectively controls the flow of hydraulic fluid from one of the master cylinder 106 and SAP 112 to the 2P3W valve output 136, which is hydraulically connected to the first pair of wheel brakes 102. The 2P3W valve 134 places the first pair of wheel brakes 102 in fluid communication with SAP 112 in normal, non-faulty braking mode and in fluid communication with the master cylinder in manual push-over braking mode. For example, if SAP112 and / or 2P3W valve 134 become inoperable, at least temporarily, for some reason, 2P3W valve 134 will remain in the non-energized position shown in the figure, allowing master cylinder 104 to push pressurized fluid through to the first pair of wheel brakes 102, and still providing some "fail-mode" stop functionality to brake system 100 in manual push-over braking mode. As another example, in the event of certain types of external leakage failures causing at least partial emptying of the reservoir, brake system 100 may be intentionally placed in manual push-over mode to prevent accidental air introduction into brake system 100. Manual push-over mode may also be intentionally triggered in the event of electronic control errors or predetermined types of failures.

[0024] More specifically, each isolation / relief control valve assembly may be in fluid communication (e.g., sequential fluid communication) with at least one selected of the 2P3W valve output 136 and the second SAP output 120 to selectively receive pressurized hydraulic fluid therefrom. Therefore, it is conceivable that the 2P3W valve 134 will be energized into... Figure 1 The reverse ("reversed") position is shown for normal, non-faulty braking mode operation of the braking system 100. In the energized position, the 2P3W valve 134 "blocks" pressurized fluid from the master cylinder 104 while routing / "allowing" pressurized fluid from the SAP 112 to the first pair of wheel brakes 102 via the 2P3W valve output 136. It should be noted that the SAP 112 is directly connected to the second pair of wheel brakes 102 via the second SAP output 120. Therefore, when the system is in manual push-over standby braking mode, the second pair of wheel brakes 102 will not receive pressurized fluid from the SAP 112.

[0025] Refer again Figure 1The isolation / release control valve device can be associated with each of the first and second pairs of wheel brakes 102. Each isolation / release control valve device includes an isolation valve 138 and a release valve 140 for providing a desired fluid route to the associated wheel brake 102. A reservoir 114 is hydraulically connected to the master cylinder 104 and each isolation / release control valve device. Each isolation / release control valve device includes a correspondingly tandemly arranged isolation valve 138 and release valve 140. The normally open isolation valve 138 of each isolation / release control valve device is hydraulically located between the corresponding wheel brake 102 and the master cylinder 104, and the normally closed release valve 140 of each isolation / release control valve device is hydraulically located between the corresponding wheel brake 102 and the reservoir 114 of the corresponding wheel brake 102.

[0026] The isolation / release control valve device can selectively provide slip control to at least one wheel brake 102 in the system that is powered by another pressurized hydraulic fluid source. More broadly, the isolation / release control valve device and / or other valves of the braking system 100 (any of which may be solenoid-operated and have any suitable configuration) can be used to help provide controlled braking operation, such as (but not limited to) ABS, traction control, vehicle stability control, dynamic rear wheel proportional control, regenerative braking hybrid, and autonomous braking.

[0027] The first traction control (“TC”) isolation valve 142 is hydraulically inserted between the first pair of wheel brakes 102 and the first SAP output 118 and MC output 110 via the 2P3W valve 134. The second traction control (“TC”) isolation valve 144 is hydraulically inserted directly between the second pair of wheel brakes 102 and the second SAP output 120—that is, there is no intermediate valve, but it is conceivable that one or more filters and / or sensors may be present in the “direct” intermediate position.

[0028] More specifically, the first traction control isolation valve 142 can be hydraulically inserted between the first SAP output 118 and the isolation / release control valve device of the first pair of wheel brakes 102. Similarly, the second traction control isolation valve 144 can be hydraulically inserted between the second SAP output 120 and the isolation / release control valve device of the second pair of wheel brakes 102.

[0029] An auxiliary power transmission unit (“PTU”) 146 is configured to selectively supply pressurized hydraulic fluid at a first PTU output 148 and a second PTU output 150, respectively, for actuating first and second pairs of wheel brakes 102 in at least one of a normal non-failure braking mode and a standby braking mode. The auxiliary power transmission unit 146 includes an electric PTU motor 152 configured to selectively pressurize hydraulic fluid by transmitting rotational motion to at least two pump pistons 154, wherein at least one pump piston 154 is associated with each of the first and second pairs of wheel brakes 102. The pump pistons 154 are driven by the electric PTU motor 152, which is different from the electric SAP motor 122 of SAP 112. The electric PTU motor 152 transmits prime mover power to each pump piston 154 to selectively supply pressurized hydraulic fluid to the isolation / release control valve assembly of at least one wheel brake 102 associated with the pump piston 154. Figure 1 In the brake system 100 shown, one pump piston 154 is associated with two wheel brakes 102, so there are a total of two pump pistons 154 in the brake system 100. However, it is conceivable that those skilled in the art can provide any desired number of pump pistons 154 and configuration of auxiliary power transmission unit 146 for the desired use environment.

[0030] For example, the two pump pistons 154 shown in the figure can each supply pressurized hydraulic fluid to a corresponding one of the first PTU output 148 and the second PTU output 150, and each of the first PTU output 148 and the second PTU output 150 supplies fluid (optionally via a corresponding isolation / release control valve device) to actuate the first and second pair of wheel brakes 102 in at least one of a normal non-failure braking mode and a standby braking mode. In some configurations of the brake system 100, it is envisioned that multiple pump pistons 154 can be associated with each of the first PTU output 148 and the second PTU output 150. For example, each of the first SAP output 118 and the second SAP output 120 can be in fluid communication with at least one pump piston 154 via at least a corresponding first traction control isolation valve 142 or a second traction control isolation valve 144 to selectively supply pressurized hydraulic fluid thereto. In this configuration, the auxiliary PTU 146 selectively pressurizes the pressurized hydraulic fluid from the reservoir 114 to supply pressurized hydraulic fluid to at least one pair of wheel brakes 102 in at least one of the normal non-failure braking mode and the standby braking mode.

[0031] The auxiliary power transmission unit 146 (also referred to as the "auxiliary brake module") of the brake system 100 can act as a pressure source to provide the desired pressure level to selected wheel brakes 102 in a standby or "failure" situation when the master cylinder 104 and / or SAP 112 are unable to supply fluid to selected wheel brakes 102 for some reason. Therefore, the auxiliary power transmission unit 146 and SAP 112 are indirectly or directly fluidly connected to the reservoir 114 to exchange hydraulic fluid between these components as needed.

[0032] As can be seen, each isolation / relief control valve device in the brake system 100 shown in the figure is in direct or indirect fluid communication with a selected one of the first SAP output 118 and the second SAP output 120, and a selected one of the first PTU output 148 and the second PTU output 150, to selectively receive pressurized fluid therefrom, for example, during different braking modes or as required. Those skilled in the art can easily configure the brake system 100 for any specific purpose as needed.

[0033] The auxiliary power transmission unit 146 can be used to selectively supply hydraulic fluid to at least one wheel brake 102 in standby braking mode, but also in enhanced braking mode, which can occur alone and / or simultaneously with standby braking mode or non-faulty normal braking mode. Examples of suitable enhanced braking mode functions available to the brake system 100 include, but are not limited to, "overpressure" (whereby, for example, a higher pressure than normally available from SAP 112 is supplied to a particular brake via a corresponding first traction control isolation valve 142 or second traction control isolation valve 144) and "volume supplement" (whereby more fluid is supplied to a particular brake than normally available from SAP 112). For example, in at least one of the normal non-faulty braking mode and standby braking mode, the auxiliary power transmission unit 146 can supply boosted (higher pressure than available from SAP 112) hydraulic fluid to at least one of the first PTU output 148 and the second PTU output 150.

[0034] The braking system 100 also includes at least one electronic control unit (ECU) 156 for selectively controlling at least one of the SAP 112, auxiliary power transmission unit 146, and 2P3W valve 134 in response to a brake signal from the brake travel sensor 108, wherein a first ECU 156A and a second ECU 156B have been shown and described herein. ECUs 156A and 156B may include a microprocessor and other circuitry. ECUs 156A and 156B receive various signals, process signals, and control the operation of various electrical components of the corresponding braking system 100 in a wired and / or wireless manner in response to the received signals. ECUs 156A and 156B may be connected to various sensors, such as a reservoir level sensor 116, a pressure sensor, a travel sensor, a switch, a wheel speed sensor, and a steering angle sensor. ECUs 156A and 156B can also be connected to external modules (not shown) to receive information related to the vehicle's yaw rate, lateral acceleration, longitudinal acceleration, or other vehicle operating characteristics for, for example (but not limited to), controlling the braking system 100 during vehicle braking, stability control, or other operating modes. Additionally, ECUs 156A and 156B can be connected to an instrument panel to collect and provide information related to warning indicators such as the ABS warning light, brake fluid level warning light, and traction control / vehicle stability control indicator. It is conceivable that at least one of ECUs 156A and 156B can be integrated, for example, into the SAP 112 and / or auxiliary powertrain unit 146.

[0035] The first ECU 156A and the second ECU 156B (when both are present) can divide the control tasks of the brake system 100 in any desired manner and can be easily configured by those skilled in the art for the specific use environment of the brake system, although it is conceivable that any control task performed by one or more ECUs 156 will be accomplished in response to at least one brake pressure signal from a pressure sensor and / or a brake signal generated by a brake travel sensor 108. For example, the first ECU 156A can operatively control the electric SAP motor 122 and / or the electric PTU motor 152, as well as any desired isolation / relief control valve device, and / or at least one of the first traction control isolation valve 122 and the second traction control isolation valve 124. The second ECU 156B can operatively control the electric PTU motor 152, at least one isolation / relief control valve device, and / or at least one of the first traction control isolation valve 122 and the second traction control isolation valve 124. When only one ECU 156 exists, the electronic control components in other brake system components can be controlled by a single ECU 156 as needed.

[0036] As an example, in certain usage environments, the 2P3W valve 134 and / or simulator valve 128 may be of a dual-winding type to help provide redundancy in the system. In these example usage environments, a first electronic control unit 156A selectively controls the 2P3W valve 134, simulator valve 128, and SAP 112, and a second electronic control unit 156B selectively controls the 2P3W valve 134, simulator valve 128, and auxiliary PTU 146, all of which are controlled at least in part in response to brake signals from brake travel sensors 108 communicating with the respective first ECU 156A or second ECU 156B. This redundant control of the simulator valve 128 facilitates pedal simulation during a standby boost mode powered by the auxiliary PTU 146 should the first electronic control unit 156A fail. Similarly, if the first electronic control unit 156A is unable to provide power boost for some reason, the redundant control of the 2P3W valve 134 can help keep the backup boost function available by promoting the establishment of pressure above the master cylinder pressure by at least one pump 154 ​​in the auxiliary PTU 146, and promoting the return flow to the reservoir 114 via the corresponding first traction control isolation valve 142 or second traction control isolation valve 144 (which controls the pressure) and SAP 112 (which is pushed back by the pump flow if discharge is required).

[0037] The term "brake pressure signal" has been referred to above as at least one input, to which the ECU 156 can control one or more other components of the braking system 100 to achieve a desired braking result for a specific operating environment. One potential source of the brake pressure signal is a brake pressure sensor. For example, as shown, the braking system 100 may include at least one brake pressure sensor 158 hydraulically inserted along the output terminal 136 of the 2P3W valve, which senses the hydraulic pressure within the 2P3W valve output terminal 136 and responsively generates a brake pressure signal.

[0038] Any desired number and type of filters 160 can be supplied to the brake system 100 for a specific operating environment; multiple filters 160 are shown in the figure, but are not numbered for clarity. For example, a first filter 160A can be hydraulically inserted between the master cylinder 104 and the 2P3W valve 134 along the MC output 110. A second filter 160B can be hydraulically inserted between the SAP 112 and the 2P3W valve 134 along the first SAP output 118. As another example, a third filter 160C can be hydraulically inserted between the SAP 112 and the second traction control isolation valve 144 along the second SAP output 120. The first filter 160A, the second filter 160B, and / or the third filter 160C (if present) can help limit debris from entering the 2P3W valve 134 or other components of the brake system 100 from the respective master cylinder 104 or SAP 112.

[0039] Any desired one or more wheel brakes 102 may also include, or instead include, electrical components, such as the brake motor 162 shown in the figure, for selectively actuating the corresponding wheel brake 102 in service braking and / or parking braking modes. If a brake motor 162 is present, it is typically (but not necessarily) used on the rear wheel brakes 102 to provide redundancy or supplementation to the hydraulic actuation characteristics of these wheel brakes 102. Those skilled in the art can readily provide any desired brake motor 162 capacity to a particular braking system 100.

[0040] like Figure 1 As shown in the braking system 100, the reservoir 114, master cylinder 104, and / or SAP 112 may be co-located in a first housing (indicated schematically by dashed line "1"), while the auxiliary power transmission unit 146 may be located in a second housing (indicated schematically by dashed line "2"), spaced apart from the first housing. Alternatively, as... Figure 1 As shown, the isolation / release control valve assembly and / or the first traction control isolation valve 142 and the second traction control isolation valve 144 may also be located in the second housing. Those skilled in the art can readily provide suitable housing arrangements for the components of the braking system 100 for specific operating environments.

[0041] Those skilled in the art can provide and configure the first and second housings (and included / co-located components) of any braking system 100 for a particular purpose based on a variety of factors, including but not limited to achieving the desired results in at least one aspect of design, manufacture, service, space utilization in a vehicle, cost, size, regulatory compliance, etc.

[0042] As mentioned above, Figure 1A configuration of a vertically split braking system 100 is depicted, wherein a first pair of wheel brakes 102 includes a left front wheel brake and a right front wheel brake, and a second pair of wheel brakes 102 includes a left rear wheel brake and a right rear wheel brake. As another example, Figure 2 (Other aspects and) Figure 1 (Similarly) A configuration of a diagonally split braking system 100 is described, wherein a first pair of wheel brakes 102 includes a left front wheel brake and a right rear wheel brake, and a second pair of wheel brakes 102 includes a right front wheel brake and a left rear wheel brake. Likewise, those skilled in the art can provide a braking system 100 appropriately configured for a particular use environment based on the teachings herein.

[0043] Those skilled in the art will consider providing various other components, such as electric service brake motors and / or parking brake motors, to achieve the desired configuration for a specific operating environment in any of the braking systems described herein. For example, although Figure 1 Multiple filters and pressure sensors (e.g., pressure sensor 158 and filter 160) are shown, but for the sake of brevity, a detailed description thereof is omitted herein, as it is readily apparent to those skilled in the art how filters, sensors, and any other components of a desired number, location, and / or operation can be provided according to the specific use environment required by the invention.

[0044] Unless the context clearly indicates otherwise, the singular forms “a” and “the” used herein also include the plural forms. It should also be understood that the terms “comprising” and / or “including” as used herein may specify the presence of the stated feature, step, operation, element, and / or component, but do not exclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof.

[0045] As used herein, the term “and / or” can include any and all combinations of one or more of the related listed items.

[0046] It should be understood that when referring to an element being "on," "attached" to, "connected" to, "joined" with, "in contact with," or "adjacent" to another element, the element may be directly on, attached to, connected to, joined to, in contact with, or adjacent to the other element, or there may be intermediate elements present. Conversely, when referring to an element being, for example, directly "on," "directly attached" to, "directly connected" to, "directly joined" to, "directly in contact with," or "directly adjacent" to another element, there are no intermediate elements present. Those skilled in the art should also understand that a structure or feature described as being "directly adjacent" to another feature may have a portion overlapping with or below the adjacent feature, while a structure or feature being "adjacent" to another feature may not have a portion overlapping with or below the adjacent feature.

[0047] For ease of description, this document may use spatial relative terms such as “below,” “under,” “lower,” “above,” “upper,” “proximal,” and “farthest” to describe the relationship between one element or feature shown in the figure and another element or feature. It should be understood that, in addition to the orientation shown in the figure, these spatial relative terms may also cover different orientations of the device during use or operation. For example, if a device in the figure is inverted, an element described as being “below” or “under” other elements or features would be located “above” other elements or features.

[0048] The phrase “at least one of X and Y” as used in this article can be interpreted as including X, Y, or a combination of X and Y. For example, if an element is described as having at least one of X and Y, then that element may contain X, Y, or a combination of X and Y at a given time, and its selection may change over time. Conversely, the phrase “at least one of X” can be interpreted as including one or more Xs.

[0049] It should be understood that although terms such as "first," "second," etc., may be used herein to describe various elements, these elements should not be limited by these terms. These terms are used only to distinguish individual elements. Therefore, the "first" element discussed below may also be referred to as the "second" element without departing from the teachings of this disclosure. Unless otherwise expressly stated, the order of operations (or steps) is not limited to the order shown in the claims or drawings.

[0050] While various aspects of this disclosure have been specifically shown and described with reference to the foregoing examples, those skilled in the art will understand that various additional aspects can be contemplated. For example, the specific methods of using the device described above are merely illustrative; those skilled in the art can readily determine any number of tools, sequences of steps, or other means / options to place the device or its components in a position substantially similar to that shown and described herein. For clarity of reference, certain repeating components are not specifically numbered, but those skilled in the art will understand, based on the numbered components, the element numbers that should be associated with the unnumbered components; the mere presence of element numbers in the figures is not intended to distinguish similar components. The structures and components may be integrally formed as a single monolithic piece or a single unit, or composed of individual sub-components, both of which may employ any suitable stock or custom components and / or any suitable materials or combinations of materials. The structures and components may be for single use or reuse as required by a specific usage environment. Any component may be equipped with user-perceptible markings to indicate information such as the component's material, configuration, at least one dimension, etc., which may help the user select a component from a range of similar components for a specific usage environment. The “predetermined” state can be determined at any time before the manipulated structure actually reaches that state, and the “predetermined” state can occur no later than before the structure reaches the predetermined state. The term “basic” as used herein indicates that the mass largely (but not necessarily completely) conforms to the specified requirements—“basic” mass allows for the inclusion of some relatively small non-mass items. Although some components described herein are shown as having specific geometries, all structures of this disclosure can have any suitable shape, size, configuration, relative relationship, cross-sectional area, or any other physical property to meet the needs of a particular application. Any structure or feature described with reference to one aspect or configuration can be applied alone or in combination with other structures or features to any other aspect or configuration, as it is impractical to describe each aspect and configuration discussed herein as having all the options discussed for all other aspects and configurations. Any apparatus or method incorporating any of these features should be understood to fall within the scope of this disclosure, determined based on the appended claims and any equivalents thereof.

[0051] Other aspects, objectives, and advantages can be obtained by studying the accompanying drawings, the disclosure, and the appended claims.

Claims

1. A fault-tolerant braking system, the braking system comprising a two-wheel manual push-over device for selectively actuating a first pair of wheel brakes and a second pair of wheel brakes, the system comprising: Storage; A master cylinder that provides a brake signal in response to actuation of a brake pedal connected to the master cylinder, the master cylinder being selectively operable during manual push-over mode by actuation of the brake pedal to generate brake actuation pressure to at least one MC output for hydraulically actuating the first pair of wheel brakes; A single-acting plunger SAP, which can be operated by actuation of an electric SAP motor during normal non-fault braking mode to generate brake actuation pressures at a first SAP output and a second SAP output for hydraulically actuating the first pair of wheel brakes and the second pair of wheel brakes, respectively. A two-position three-way 2P3W valve is hydraulically connected to the MC output, the first SAP output, and the first pair of wheel brakes. The 2P3W valve selectively controls the flow of hydraulic fluid from one of the master cylinder and the SAP to the 2P3W valve output, which is hydraulically connected to the first pair of wheel brakes. An auxiliary power transmission unit (PTU) is configured to selectively provide pressurized hydraulic fluid at a first PTU output and a second PTU output to actuate a first pair of wheel brakes and a second pair of wheel brakes in at least one of a normal non-failure braking mode and a standby braking mode. The auxiliary power transmission unit includes an electric PTU motor configured to selectively pressurize the hydraulic fluid by transmitting rotational motion to at least two pump pistons, each pump piston providing pressurized hydraulic fluid to a corresponding one of the first PTU output and the second PTU output, each of the first PTU output and the second PTU output providing fluid to a corresponding pair of the first pair of wheel brakes and the second pair of wheel brakes. as well as An electronic control unit (ECU) is configured to selectively control at least one of the SAP, the auxiliary power transmission unit, and the 2P3W valve in response to the brake signal. The auxiliary power transmission unit and the SAP are fluidly connected to the storage device; and The 2P3W valve connects the first pair of wheel brakes to the SAP in normal, non-faulty braking mode and to the master cylinder in manual push-over braking mode.

2. The braking system of claim 1, wherein the braking system comprises a first traction control isolation valve, the first traction control isolation valve being hydraulically inserted between the first pair of wheel brakes and the first SAP output and the MC output via the 2P3W valve; and The second traction control isolation valve is hydraulically inserted directly between the second pair of wheel brakes and the second SAP output.

3. The braking system according to claim 2, wherein, The ECU selectively controls the first traction control isolation valve and the second traction control isolation valve.

4. The braking system of claim 1, wherein the braking system includes a brake pressure sensor hydraulically inserted along the output end of the 2P3W valve, the brake pressure sensor sensing the hydraulic pressure within the output end of the 2P3W valve and responsively generating a brake pressure signal, wherein, The ECU controls at least one of the SAP, the auxiliary power transmission unit, and the 2P3W valve in response to the brake pressure signal.

5. The braking system of claim 1, wherein the braking system includes an isolation / release control valve device associated with each of the first pair of wheel brakes and the second pair of wheel brakes, each isolation / release control valve device being controlled by the electronic control unit.

6. The braking system according to claim 5, wherein, Each isolation / relief control valve device is in fluid communication with a selected one of the output terminals of the 2P3W valve and the second SAP to selectively receive pressurized hydraulic fluid therefrom.

7. The braking system according to claim 5, wherein, The first traction control isolation valve is hydraulically inserted between the 2P3W valve and the isolation / release control valve device of the first pair of wheel brakes, and wherein the second traction control isolation valve is hydraulically inserted between the output end of the second PTU and the isolation / release control valve device of the second pair of wheel brakes.

8. The braking system of claim 1, wherein the braking system includes a pedal simulator in selective fluid communication with the master cylinder, the pedal simulator being used to provide a predetermined brake pedal response.

9. The braking system of claim 8, the braking system comprising a simulator valve hydraulically inserted between at least one of the pedal simulator and the chambers of the reservoir and the master cylinder.

10. The braking system according to claim 1, wherein, The 2P3W valve is a dual-winding type, and the electronic control unit is a first electronic control unit that selectively controls the 2P3W valve and the SAP. The braking system includes a second electronic control unit that selectively controls the 2P3W valve and the auxiliary PTU. Both the first electronic control unit and the second electronic control unit control the corresponding SAP and auxiliary PTU in response to the braking signal.

11. The braking system of claim 10, wherein the braking system comprises: A pedal simulator, which is in selective fluid communication with the master cylinder to provide a predetermined brake pedal response; And a simulator valve, which is hydraulically inserted between at least one of the pedal simulator and the chambers of the reservoir and the master cylinder, wherein the simulator valve is a dual-winding type, and both the first electronic control unit and the second electronic control unit selectively control the simulator valve.

12. The braking system of claim 10, wherein the braking system includes an isolation / release control valve device associated with each of the first pair of wheel brakes and the second pair of wheel brakes, wherein, The second electronic control unit controls each of the isolation / relief control valves.

13. The braking system according to claim 10, wherein, The second electronic control unit controls the first traction control isolation valve and the second traction control isolation valve.

14. The braking system according to claim 1, wherein, Each of the first SAP output and the second SAP output is in fluid communication with the pump output of at least one pump piston via a corresponding first traction control isolation valve or a second traction control isolation valve to selectively supply pressurized hydraulic fluid to the pump output. The auxiliary PTU selectively pressurizes the pressurized hydraulic fluid from the SAP to supply pressurized hydraulic fluid to at least one pair of wheel brakes in at least one of a normal non-failure braking mode and a standby braking mode.

15. The braking system according to claim 1, wherein, The storage device, the master cylinder, and the SAP are housed in a first housing, and the auxiliary power transmission unit is located in a second housing, which is spaced apart from the first housing.

16. The braking system of claim 1, wherein the braking system includes an isolation / release control valve device associated with each of the first pair of wheel brakes and the second pair of wheel brakes, each isolation / release control valve device being controlled by the electronic control unit; and in, The storage unit, the master cylinder, and the SAP are housed in a first housing, and the auxiliary power transmission unit and the isolation / release control valve device are located in a second housing, which is spaced apart from the first housing.

17. The braking system of claim 1, wherein the braking system comprises a first filter hydraulically inserted between the master cylinder and the 2P3W valve along the output end of the MC, a second filter hydraulically inserted between the SAP and the 2P3W valve along the output end of the first SAP, and a third filter hydraulically inserted between the SAP and the second traction control isolation valve along the output end of the second SAP, wherein... The first filter, the second filter, and the third filter restrict debris from entering the 2P3W valve from the corresponding master cylinder or SAP.

18. The braking system of claim 1, wherein the braking system includes a pair of rear brake motors for selectively and electrically actuating respective rear wheel brakes.

19. The braking system according to claim 1, wherein the braking system is a vertically segmented system, The first pair of wheel brakes includes a left front wheel brake and a right front wheel brake, and the second pair of wheel brakes includes a left rear wheel brake and a right rear wheel brake.

20. The braking system according to claim 1, wherein the braking system is a diagonally segmented system, wherein, The first pair of wheel brakes includes a left front wheel brake and a right rear wheel brake, and the second pair of wheel brakes includes a right front wheel brake and a left rear wheel brake.

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