Energy storage device having a quick fill supply valve and brake system using the same

Abstract

The invention relates to an energy accumulator with a quick-fill supply valve and a brake system using the same. The accumulator assembly includes a medium pressure accumulator having an MPA chamber that includes a brake side passage and a pump side passage. An unpowered MPA fill valve is fluidly disposed between the pump-side passage of the MPA chamber and the source of pressurized hydraulic fluid. The MPA filling valve seat is positioned along the MPA filling valve fluid path. The MPA filling valve poppet valve is configured to reciprocate between a poppet valve rest position and a poppet valve closed position in which the MPA filling valve poppet valve shoulder contacts the MPA filling valve seat to block fluid flow through the MPA filling valve seat. A powered MPA one-way valve is fluidly disposed between the brake-side passage and at least one corresponding wheel brake.

Description

Technical Field

[0001] The present disclosure relates to an apparatus and method for using an accumulator having a fast-fill supply valve and a braking system using such an accumulator, and more particularly to a method and apparatus for a braking system having an intermediate-pressure accumulator having an associated two-way solenoid valve. Background Art

[0002] A braking system may include an anti-lock control that includes: a hydraulic brake pressure generator; a brake pressure regulator disposed in a pressure fluid line between the brake pressure generator and a wheel brake and operative to change a brake pressure by changing a volume of a chamber containing a hydraulic fluid; a sensor operative to determine a wheel rotation behavior; and an electronic circuit operative to process the sensor signals and to generate a brake pressure control signal. The braking system may also include an anti-lock control and a traction slip control that may use the brake pressure regulator to control vehicle braking.

[0003] For some use environments (e.g., “peak application,” when a user “jams” on the brakes), it may be desirable to supply pressurized hydraulic fluid to the brakes at an accelerated rate. Thus, in some use environments, storing the pressurized hydraulic fluid closer to the brakes than the pressurized hydraulic fluid source may help facilitate a rapid braking response.

[0004] For example, some braking systems include a “running clearance” distance between a brake pad and a rotor to avoid unwanted drag and wear on the brakes when the brakes are not in use. Particularly in a “peak application” scenario, a user may desire to quickly occupy this running clearance distance to avoid a delay in brake actuation (or a driver's perception of the delay).

[0005] Descriptions of prior art braking systems are in U.S. Patent No. 10,730,501, issued Aug. 4, 2020, to Blaise Ganzel and entitled “Vehicle Braking System with Auxiliary Pressure Source,” U.S. Patent Application Publication No. 2020 / 0307538, published Oct. 1, 2020, by Blaise Ganzel and entitled “Braking System with Multiple Pressure Sources,” and U.S. Patent Application Publication No. 2023 / 0048447, published Feb. 16, 2023, by Blaise Ganzel and entitled “Apparatus and Method for Controlling a Hydraulic Braking System Including Manual Propulsion,” all of which are incorporated herein by reference in their entireties for various purposes. Summary of the Invention

[0006] On the one hand, an accumulator assembly is described, either alone or in combination with any other aspect. The accumulator assembly includes a medium-pressure accumulator having an MPA chamber that includes at least one brake-side passage adjacent a first end of the MPA chamber and at least one pump-side passage adjacent the first end of the MPA chamber. An MPA piston is arranged to reciprocate longitudinally within the MPA chamber in response to a predetermined amount of hydraulic fluid flowing through at least one of the pump-side passage and the brake-side passage. An MPA biasing spring is arranged to urge the MPA piston toward the first end of the MPA chamber. A non-powered MPA fill valve is fluidly disposed between the pump-side passage of the MPA chamber and a source of pressurized hydraulic fluid. The MPA fill valve includes an MPA fill valve chamber that selectively fluidly communicates the pump-side passage of the MPA chamber with the source of pressurized hydraulic fluid via an MPA fill valve fluid path. An MPA fill valve seat is positioned along the MPA fill valve fluid path and is at least partially defined by an inner wall of the MPA fill valve chamber. An MPA fill valve lift valve is configured to reciprocate between a lift valve rest position and a lift valve closed position, in which the MPA fill valve lift valve shoulder contacts the MPA fill valve seat to block fluid flow along the MPA fill valve fluid path past the MPA fill valve seat. An MPA fill valve biasing spring urges the MPA fill valve lift valve toward the lift valve closed position. The MPA fill valve lift valve selectively reciprocates in response to at least one of a fluid pressure differential between the source of pressurized hydraulic fluid and the MPA chamber and a biasing force from the MPA valve biasing spring. A powered MPA check valve is fluidly disposed between the brake-side passage of the MPA chamber and at least one corresponding wheel brake. The MPA check valve includes an MPA check valve chamber that selectively fluidly communicates the brake-side passage of the MPA chamber and at least one corresponding wheel brake via an MPA check valve fluid path. An MPA check valve seat is positioned along the MPA check valve fluid path and is defined by an inner wall of the MPA check valve chamber. An MPA check valve lift valve is configured to reciprocate between a check valve lift valve open position and a check valve lift valve closed position, in which the MPA check valve lift valve shoulder selectively contacts the MPA check valve seat to block fluid flow along the MPA check valve fluid path past the MPA check valve seat. The reciprocation of the MPA check valve lift valve occurs at least in part in response to a predetermined amount of fluid pressure differential between the MPA chamber and at least one corresponding wheel brake. BRIEF DESCRIPTION OF THE DRAWINGS

[0007] For a better understanding, reference may be made to the accompanying drawings, which are not drawn to scale and in which:

[0008] Figure 1 is a schematic cross-sectional view of a portion of a braking system according to one aspect of the present invention;

[0009] Figure 2 is Figure 1 a schematic cross-sectional view of the part of the braking system in a first state;

[0010] Figure 3 is Figure 2 a schematic detail view of region "3" of

[0011] Figure 4 is Figure 2 a schematic cross-sectional view of the part in a second state;

[0012] Figure 5 is Figure 2 a schematic cross-sectional view of the part in a third state;

[0013] Figure 6 is Figure 5 a schematic detail view of region "6" of

[0014] Figure 7 is Figure 1 a schematic cross-sectional view of another part of the braking system in a first state;

[0015] Figure 8 is Figure 2 a schematic cross-sectional view of the part in a second state;

[0016] Figure 9 is Figure 2 a schematic cross-sectional view of the part in a third state;

[0017] Figure 10 is a schematic hydraulic diagram of an exemplary braking system incorporating the parts of Figure 1 , Figure 5 and Figure 8 ;

[0018] Figure 11 is Figure 10 a schematic perspective front view of an exemplary physical arrangement of the braking system; and

[0019] Figure 12 is Figure 11 a schematic perspective rear view of the exemplary physical arrangement shown in DETAILED DESCRIPTION

[0020] 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 belongs.

[0021] The present invention includes any combination of the following features, consists of any combination of the following features, or consists essentially of any combination of the following features.

[0022] Figure 1 An accumulator assembly 100 is schematically shown, which includes a medium-pressure accumulator (MPA) 102, a non-powered MPA fill valve 104, and a powered MPA check valve 106. The term "medium pressure" is used to indicate that the accumulator 102 is configured to maintain an operating pressure, for example, between about 3.9 bar and about 5.5 bar, in some operating environments. This pressure capacity can be adjusted as needed by one of ordinary skill in the art by changing the size, shape, available spring force, construction, and / or other characteristics of at least one component of the medium-pressure accumulator 102. The accumulator assembly 100 can be used, for example, in combination with a braking system, as will be discussed in more detail below. As a result of this "medium pressure" capability, the accumulator assembly 100 can have the ability to usefully store (temporarily or permanently) pressurized hydraulic fluid and supply the pressurized hydraulic fluid to other components of the braking system that are in positions where it is not practical to locate a low-pressure accumulator (not shown). The accumulator assembly 100 can be housed in the block housing 108 schematically shown in these figures, which can: define a plurality of components of the accumulator assembly 100; assist in assembling and maintaining the plurality of components of the accumulator assembly 100 into an assembled device; and / or provide other housing, assembly, and / or maintenance functions for any other components of the braking system as needed.

[0023] The medium-pressure accumulator 102 includes an MPA chamber 110, which includes at least one brake-side passage 112 at and / or adjacent to a first end 114 of the MPA chamber 110 and at least one pump-side passage 116 also at and / or adjacent to the first end 114 of the MPA chamber 110. As needed, the MPA chamber 110 can communicate with the atmosphere at a location spaced apart from the first end 114. The MPA piston 118 is configured to reciprocate longitudinally within the MPA chamber 110 in response to a predetermined amount of hydraulic fluid flowing through at least one of the pump-side passage 116 and the brake-side passage 112. The "longitudinal" direction referred to herein with respect to the MPA fill valve 104 is substantially parallel to the arrow "L" and is depicted as a vertical direction in the Figure 2 orientation shown. The MPA piston 118 can include at least one piston seal 120, a piston passage 122 for allowing "through" the MPA piston 118, or any other desired features that can be configured by one of ordinary skill in the art. An MPA biasing spring 124 is provided for urging the MPA piston 118 toward the first end 114 of the MPA chamber 110.

[0024] The non-powered MPA fill valve 104 is fluidly disposed between the pump-side passage 116 of the MPA chamber 110 and a source of pressurized hydraulic fluid, which can be at least one of a pump piston of a secondary brake module and a master cylinder, as will be referenced Figure 10as discussed with respect to the braking system. The MPA fill valve 104 includes an MPA fill valve cavity 126 that selectively fluidly couples a pump side passage 116 of the MPA cavity 110 and a pressurized hydraulic fluid source via an MPA fill valve fluid path that is schematically shown as FVP in Figure 3 and discussed in more detail below. The MPA fill valve seat 128 is positioned along the MPA fill valve fluid path FVP and is at least partially defined by an inner wall 130 of the MPA fill valve cavity 126. The MPA fill valve poppet 132 is configured to reciprocate at least between a poppet rest position and a poppet closed position, as will now be further discussed with reference to Figures 2 to 6 .

[0025] Turning to Figure 2 and Figure 3 , the MPA fill valve cavity 126 includes an annular groove 134 adjacent to the pump side passage 116 of the MPA cavity 110 (e.g., extending continuously from the pump side passage 116 of the MPA cavity 110). The annular groove 134 is configured to hold an oriented MPA lip seal 136 therein. The MPA lip seal 136 selectively permits hydraulic fluid flow along the MPA fill valve fluid path FVP toward the MPA cavity 110 past the MPA lip seal 136, which is a one-way fluid flow path during many operating phases of the MPA fill valve 104 at least due to the oriented sealing characteristics of the MPA lip seal 136.

[0026] However, it is contemplated that in certain situations (which are contemplated to occur very rarely over the entire expected life of the accumulator assembly 100), the MPA lip seal 136 may selectively permit airflow along the MPA fill valve fluid path FVP "backward" in a direction opposite to the direction indicated by the arrow along FVP toward the pressurized hydraulic fluid source past the MPA lip seal 136. In the configuration shown in Figure 2 and Figure 3 , the MPA fill valve poppet 132 is in a fully retracted "initial" position in which the accumulator assembly 100 is provided to, for example, a vehicle manufacturer for initial assembly into a braking system.

[0027] The MPA fill valve fluid path FVP can include an MPA orifice 135 therealong, which is for restricting fluid flow along the MPA fill valve fluid path FVP and into the medium pressure accumulator 102. The MPA orifice can be configured by one of ordinary skill in the art for a particular use application and can be about 0.25 mm in diameter for the components of the accumulator assembly 100 given by way of example herein. The MPA orifice 135 and the fluid flow restriction it provides can help avoid an undesired "dump" or "circulation" of fluid volume that exits through the MPA check valve 106 and then only finally returns to the MPA chamber 110 through the MPA fill valve 104.

[0028] In Figure 2 and Figure 3 the initial position, the MPA fill valve lift valve 132 is configured to provide an MPA bleed port function during the unpowered discharge / fill phase of the life operation of the accumulator assembly 100. The term "life operation" is used herein to mean that during the life of the brake, a particular function may occur or happen at one or more points as needed, but is not expected to occur regularly as a routine function during normal operation. This unpowered discharge / fill phase is envisioned to occur only during the initial startup of the brake system (always the first time), and / or in the unlikely event that (the entire brake system of a vehicle in repair has been at least partially drained of hydraulic fluid during non-routine maintenance and needs to be refilled). It is also envisioned that, for example, if a vehicle containing the accumulator assembly 100 is parked for an extended period of time and the pressurized hydraulic fluid within the MPA chamber 110 leaks beyond a predetermined fill amount, or as another example, if there is a "spike application" of the brake that uses a large amount of pressurized hydraulic fluid from the MPA chamber 110, then the MPA bleed port function can be used. Both of these situations may prompt the need to perform the bleed port function.

[0029] Thus, to support this seldom-needed "bleed port" or "bleed valve" function and thus remove air that is normally not needed from within the MPA chamber 110, the MPA fill valve lift valve 132 includes an MPA bypass shoulder, as Figure 3As shown at 138 in [Figure 0]. When the bleed port function is no longer needed, the MPA bypass shoulder 138 selectively contacts the inner surface of the MPA lip seal 136 to block the flow of fluid (air, hydraulic fluid, or other fluid) along the MPA fill valve fluid path FVP past the MPA lip seal 136 toward the pressurized hydraulic fluid source. As a result, when the MPA bypass shoulder 138 is in blocking contact with the MPA lip seal 136, the MPA fill valve fluid path FVP is restricted to one-way operation, allowing hydraulic fluid to pass between the oriented MPA lip seals 136 toward the MPA cavity 110. The term "blocking contact" is used herein to mean that the MPA bypass shoulder 138 is in lateral contact with the MPA lip seal 136, or that the MPA bypass shoulder 138 has "passed over" the MPA lip seal 136 toward the MPA cavity 110 such that the enlarged diameter region of the MPA fill valve lift valve 132 is in lateral contact with the MPA lip seal 136 "behind" the MPA bypass shoulder 138. The term "lateral" is used throughout the specification to mean a direction perpendicular to the longitudinal direction.

[0030] The MPA bypass shoulder 138 can be of any desired type and can extend continuously or discontinuously around the perimeter of the MPA fill valve lift valve 132. As an example of the latter, the region labeled 138 in the figure can represent a cross-section of a longitudinal groove or slotted region passing through the body of the MPA fill valve lift valve 132, the body of which has one or more slots defining the MPA bypass shoulder 138. When the MPA bypass shoulder 138 is of the groove or slotted type, the lip seal 136 will typically "bridge" laterally across such a longitudinal void, allowing air to pass through the region of the MPA bypass shoulder 138. A person of ordinary skill in the art can readily configure a particular bleed port function to provide the structure for a particular use environment.

[0031] This is the case as Figure 5 and Figure 6As shown, it includes the "rest position" of the MPA fill valve lift valve 132. In the accumulator assembly 100 configuration shown in the figure, once the power-off discharge / fill phase of the life operation of the associated braking system has been completed, or when there is no desired "bleed port" function, the distal end of the MPA fill valve lift valve 132 extends through the pump side passage 116 into the MPA chamber 110 and is at least partially retained within the MPA chamber 110, where the MPA bypass shoulder 138 is in blocking contact with the inner surface of the MPA lip seal 136. Thus, in the above example case where the MPA chamber 110 does not have the required amount of fluid, generally speaking, in response to the MPA chamber 110 containing a predetermined fill amount of hydraulic fluid, the MPA fill valve lift valve 132 is at least partially retained within the MPA chamber 110, where the MPA bypass shoulder 138 is in blocking contact with the inner surface of the MPA lip seal 136.

[0032] The MPA bypass shoulder 138 is longitudinally spaced from the MPA lift valve shoulder along the MPA fill valve lift valve 132, and the MPA lift valve shoulder is shown at 140 in Figures 2 to 6 . Referring to Figure 4 , when the MPA fill valve lift valve 132 is in the "closed" position, the MPA fill valve lift valve shoulder 140 selectively contacts the MPA fill valve seat 128 to block the fluid flow along the MPA fill valve fluid path FVP through the MPA fill valve seat 128. The reciprocating movement of the MPA fill valve lift valve 132 between the rest position (allowing fluid to flow along the FVP to the MPA chamber 110, as shown in Figure 5 and Figure 6 ) and the closed position (substantially preventing fluid from flowing along the FVP, as shown in Figure 4 ) can occur at least in part in response to the application state of at least one associated wheel brake, the relative pressures within the MPA chamber 110 and at least one other component of the accumulator assembly 100, and / or the operation of at least one associated isolation valve of the isolation / valve control valve device.

[0033] That is, the "rest position" allows pressurized hydraulic fluid from a pressurized hydraulic fluid source to travel along the MPA fill valve fluid path FVP and enter the MPA chamber 110 until the MPA piston is pushed back against the force of the MPA bias spring 124 and the MPA chamber 110 is "filled" with a predetermined fill amount of hydraulic fluid. The MPA fill valve bias spring 142 (with an anti-buckling pin 144 associated therewith) pushes the MPA fill valve lift valve 132 towards the lift valve closed position, which is reached when the MPA chamber 110 contains the predetermined fill amount of hydraulic fluid, and the MPA lift valve shoulder 140 forms a blocking contact with the MPA fill valve seat 128 accordingly. Once the MPA fill valve lift valve 132 is in the "closed" position, no further pressurized hydraulic fluid flows along the MPA fill valve fluid path FVP into the MPA chamber 110. However, in certain situations (e.g., a predetermined pressure difference between the pressurized hydraulic fluid source and the MPA chamber 110), once the MPA bypass shoulder 138 makes a blocking contact with the inner surface of the MPA lip seal 136, the hydraulic fluid can be forced to travel between the MPA fill valve 104 and the MPA chamber 110 by traveling between the MPA fill valve lift valve 132 and the MPA lip seal 136.

[0034] When the MPA chamber 110 includes the predetermined fill amount of hydraulic fluid, at least a first length of the MPA fill valve lift valve 132 is located within the MPA chamber 110. This is Figure 4 the configuration shown. In the sequence of views from Figures 4 to 5 then, the MPA fill valve lift valve 132 selectively reciprocates within the MPA fill valve chamber 110 in response to at least one of the biasing force from the MPA valve bias spring 142 and the fluid pressure difference between the pressurized hydraulic fluid source and the MPA chamber 110. (For example, the fluid pressure within the MPA chamber 110 acts to overcome the biasing force from the MPA valve bias spring 142, moving the MPA lift valve shoulder 140 away from the MPA fill valve seat 128 and thus obtaining more pressurized hydraulic fluid from the pressurized hydraulic fluid source.)

[0035] When the MPA chamber 110 substantially includes the predetermined fill amount of hydraulic fluid and / or there is a predetermined pressure difference between the MPA chamber 110 and the hydraulic fluid source, a second length of the MPA fill valve lift valve 132 (schematically shown as less than the first length of the MPA fill valve lift valve 132) extends into the MPA chamber 110 and remains located within the MPA chamber 110, as shown in Figure 5 and Figure 6As shown. Since the second length of the MPA fill valve lift valve 132 represents the amount that allows the MPA fill valve lift valve 132 to be in the "rest" position, any desired amount of pressurized hydraulic fluid is allowed to flow along the MPA fill valve fluid path FVP and / or between the MPA fill valve lift valve 132 and the lip seal 136, and to flow through the brake system in a predetermined manner; those of ordinary skill in the art can easily provide a suitably configured accumulator assembly 100 and / or brake system to achieve the desired braking performance for a particular use environment.

[0036] Alternative configurations (not shown) that can be adapted to a particular use environment include, but are not limited to: directly or indirectly attaching the MPA fill valve lift valve 132 to the MPA piston 118 to reciprocate therewith; configuring the MPA biasing spring 124 to hold the MPA fill valve lift valve 132 in reciprocating contact with the MPA piston 118 to reciprocate therewith; providing a blocking member and / or mechanism to permanently prevent the "bleed valve" fluid from flowing back upward along the MPA fill valve fluid path FVP after an initial power-off discharge / fill process; and / or intentionally leaving a small amount of air in the MPA chamber 110 after the initial power-off discharge / fill process, and subsequently optionally operating one or more other components of the brake system in a cyclic manner to provide a self-bleed function that sends the "remaining" small amount of air from the MPA chamber 110 out of the brake system.

[0037] Figures 7 to 9 The structure and operation of the power MPA check valve 106 are schematically shown. The check valve 106 is fluidly disposed between the brake side passage 112 of the MPA chamber 110 and at least one corresponding wheel brake. The MPA check valve 106 includes an MPA check valve chamber 146 that selectively fluidly connects the brake side passage 112 of the MPA chamber 110 and at least one corresponding wheel brake via the MPA check valve fluid path OVP (schematically shown in Figure 9 ). The MPA check valve seat 148 is positioned along the MPA check valve fluid path OVP and is defined by the inner wall 150 of the MPA check valve chamber 146.

[0038] The MPA check valve lift valve 152 is configured to reciprocate between a check valve lift valve open position and a check valve lift valve closed position. When the MPA check valve lift valve 152 is in the check valve lift valve closed position, the MPA check valve lift valve shoulder 154 contacts the MPA check valve seat 148 to block fluid flow along the MPA check valve fluid path OVP past the MPA check valve seat 148. The reciprocating movement of the MPA check valve lift valve 152 occurs at least in part in response to a predetermined amount of fluid pressure difference between the MPA chamber 110 and at least one corresponding wheel brake, which will be described below.

[0039] The MPA check valve 106 includes an armature 156 for switching between a first armature position and a second armature position (respectively at Figure 7 and Figures 8 to 9 ) between the MPA check valve chamber 146 for selective longitudinal reciprocation. As referred to herein with respect to the MPA check valve, the "longitudinal" direction is substantially parallel to the arrow "L" and is Figure 7 The MPA check valve 106 includes a core 158 for selectively magnetically attracting an armature 156. The core 158 is positioned longitudinally directly adjacent to a core actuation surface 160 of the armature 156. The armature 156 is longitudinally disposed between the core 158 and the MPA check valve poppet 152. The core 158 is selectively energized to Figure 7 The first armature position is Figures 8 to 9 The armature 156 is magnetically driven between the second armature position of the MPA check valve 106. The core spring 162 biases the armature 156 toward the MPA check valve poppet 152, i.e., toward the first armature position, so that the MPA check valve 106 becomes a normally closed type valve, which is then electrically (solenoid) actuated to selectively open.

[0040] In response to the armature 156 being in the first armature position, the MPA check valve poppet 152 is held in engagement with the MPA check valve seat 148 in the check valve poppet closed position. As a result, when the armature 156 is in the first armature position, the MPA check valve fluid path OVP is blocked and pressurized hydraulic fluid is not allowed to travel from the medium pressure accumulator 102 toward the wheel brakes. In response to the armature 156 being in the second armature position, the MPA check valve poppet 152 is allowed to flow in the second armature position. Figure 8 The check valve poppet valve closed position and Figure 9 Thus, depending on the position of the MPA check valve poppet 152, the MPA check valve fluid path OVP may be blocked when the armature 156 is in the second armature position, or may not be blocked at that time.

[0041] When the armature 156 is in the second armature position, the poppet spring 164 biases the MPA check valve poppet 152 toward the check valve poppet closed position and thus biases the MPA check valve poppet shoulder 154 toward sealing engagement with the MPA check valve seat 148. Again, this is Figure 8 Conversely, in response, at least in part, to the fluid pressure in the MPA chamber 110 (i.e., in the brake-side passage 112) being greater than the predetermined wheel-side fluid pressure (i.e., in the wheel-side passage indicated by 166), the MPA check valve poppet 152 is disengaged from the Figure 8 The check valve poppet valve closed position is towards Figure 9The reciprocating movement to the open position of the check valve lift valve is allowed to occur, and the predetermined wheel-side fluid pressure is related to the fluid pressure at at least one corresponding wheel brake and is optionally adjusted to account for the pressure drop that occurs in the intermediate length of the hydraulic line. When the MPA check valve lift valve 152 is pushed by the fluid pressure from the brake-side passage 112 towards Figure 9 the open position of the check valve lift valve, the MPA check valve fluid path OVP is allowed to open, and the pressurized hydraulic fluid flows along the MPA check valve fluid path OVP towards the brake through the MPA check valve 106 to facilitate "spike application" or otherwise supply the pressurized hydraulic fluid to the wheel brake in a desired manner for brake system operation.

[0042] The MPA check valve 106 can be configured and constructed in any desired manner and can be readily provided by one of ordinary skill in the art for a desired use environment. As an example, given the previously mentioned intermediate pressure, the MPA check valve fluid path OVP can be configured to: when the MPA check valve 106 is in Figure 7 the configuration, obtain a force of about 10 bar from the direction of the brake-side passage 112 (to overcome the spring force of at least one of the iron core spring 162 and the lift valve spring 164) to open, obtain about 80 mbar in Figure 8 the configuration (to overcome the force of the lift valve spring 164 and initially displace the MPA check valve lift valve 152) to start opening, and obtain about 180 mbar (to move the MPA check valve lift valve 152 completely away from the MPA check valve seat 148) to fully open to Figure 9 the configuration.

[0043] The exemplary MPA check valve 106 construction shown in the figure includes an iron core sleeve 168 at least partially housed in a housing 108, and the housing 108 also at least partially defines the MPA chamber 110. The iron core sleeve 168, when present, is configured to maintain the iron core 158 in a spaced-apart relationship with the armature 156. The armature 156 is at least partially surrounded within the iron core sleeve 168 and is guided by the iron core sleeve to selectively move longitudinally back and forth relative to the iron core 158 in response to the energization of the iron core 158. Optionally, and also as shown in the figure, the iron core sleeve 168 can completely surround the MPA check valve lift valve 152.

[0044] The iron core sleeve 168 is shown as having a reduced-diameter sleeve shoulder 170 located at the end of the MPA check valve lift valve 152 opposite the iron core 158. By including at least a portion of the inner wall 150 of the MPA check valve cavity 146 at this location on the MPA check valve 106, the sleeve shoulder 170 at least partially defines the MPA check valve seat 148. Any desired number, configuration, and type of elastomeric seal 172 to prevent fluid leakage, a retainer 174 to maintain component spacing or arrangement of the MPA check valve 106 as needed, and / or a flange 176 to hold the MPA check valve 106 within the block housing 108 can be provided by one of ordinary skill in the art for the particular use environment of the accumulator assembly 100.

[0045] Figure 10 An exemplary braking system 178 for actuating a plurality of wheel brakes 180 including a first pair of wheel brakes 180 and a second pair of wheel brakes 180 is schematically shown. The braking system 178 is shown herein as a hydraulic braking system, where braking force is applied to the braking system 178 using fluid pressure. The braking system 178 can be suitably used for ground vehicles, such as motor vehicles having four wheels, where the wheel brakes are associated with each wheel. Additionally, the braking system 178 can be provided with other braking functions, such as anti-lock braking (ABS) and other slip control features, to effectively brake the vehicle. The components of the braking system 178 can be housed in one or more blocks or housings. The block or housing can be made of a solid material, such as aluminum, that has been drilled, machined, or otherwise formed to accommodate the various components. Fluid conduits can also be formed in the block or housing.

[0046] In Figure 10 the illustrated embodiment of the braking system 178, there are four wheel brakes 180, and each wheel brake can have any suitable electrically operated and / or wheel brake structure that operates by applying pressurized brake fluid. Each wheel brake 180 can include, for example, a brake caliper mounted on the vehicle to engage a friction element (such as a brake disc) that rotates with the wheel, thereby effecting braking of the associated wheel. The wheel brakes 180 can be associated with any combination of the front and rear wheels of the vehicle on which the corresponding braking system 178 is mounted. For example, the braking system 178 can be configured as a vertically split or diagonally split system. Although one of ordinary skill in the art can readily provide suitable braking devices for a particular use environment, for the purposes of this specification, no distinction is made herein in the structures of the various wheel brakes 180. The wheel brakes 180 are described herein as including a first pair of wheel brakes 180 and a second pair of wheel brakes 180, and for descriptive purposes, the first pair of wheel brakes 180 and the second pair of wheel brakes 180 are characterized as RF / LR and LF / RR, as Figure 10As shown. However, pairs of LF / LR and RF / RR or RF / LF and RR / LR can also be specified for the brake system 178 as needed, or alternatively pairs of LF / LR and RF / RR or RF / LF and RR / LR can be specified for the brake system 178 as needed.

[0047] Also for purposes of description, it is assumed that the deceleration signal transmitter (schematically shown at 184) is configured to provide a brake signal corresponding to the desired braking action of the vehicle operator in a wired or wireless manner. The deceleration signal transmitter 184 can include, but is not limited to, a brake pedal, an autonomous brake controller, and / or any other suitable means for generating a brake signal, and the brake system 178 can be actuated in accordance with the brake signal.

[0048] The brake system 178 also includes a fluid reservoir 186. The reservoir 186 stores and holds hydraulic fluid for the brake system 178. The fluid within the reservoir 186 is preferably maintained at atmospheric pressure or approximately atmospheric pressure, but if desired, the fluid can be stored at other pressures. The reservoir 186 is Figure 10 schematically shown as having three tanks or sections to which fluid lines are connected. These sections can be separated by several inner walls within the reservoir 186 and are provided to prevent complete discharge of the reservoir 186 in the event that one of these sections is depleted due to a leak via one of the three lines connected to the reservoir 186. Alternatively, the reservoir 186 can include a plurality of separate housings. The reservoir 186 can include at least one level sensor 188 for detecting the level of one or more sections of the reservoir 186.

[0049] The motor-driven master cylinder (“MC” or “[main] power transmission unit”) 182 of the brake system 178 (which can be a dual-chamber master cylinder 182, also referred to as a tandem power transmission unit) serves as a pressure source to provide a desired pressure level to the hydraulically operated wheel brakes 180 during typical or normal non-fault braking applications. Examples of suitable MC 182 devices are disclosed in the co-pending U.S. Patent Application No. 17 / 708,070, filed on March 30, 2022, entitled “Tandem Power Transmission Unit and Brake System Using the Same” (Attorney Docket No. 211835-US-NP), which is hereby incorporated by reference in its entirety for all purposes. The master cylinder 182 can be operated during normal non-fault braking mode by actuation of the motor 190 of the master cylinder 182 to generate brake actuation pressures at a first MC output 192 and a second MC output 194, respectively, for hydraulically actuating a first pair of wheel brakes 180 and a second pair of wheel brakes 180.

[0050] After application of the brakes, fluid from the wheel brakes 180 can return to the master cylinder 182 and / or be diverted to the reservoir 186. It is also contemplated that other configurations (not shown) of the brake system 178 can include hydraulic control of only selected ones or more of the wheel brakes (the others being electrically controlled / electrically actuated). In the following aspects of the present invention, those of ordinary skill in the art will be able to readily provide such an arrangement for a desired use environment.

[0051] The secondary brake module is configured to selectively provide pressurized hydraulic fluid at a first pump outlet 196 and a second pump outlet 198, respectively, to actuate a first pair of wheel brakes 180 and a second pair of wheel brakes 180 in at least one of a normal non-fault braking mode and a standby braking mode. As Figure 10 shown, the secondary brake module includes at least one pump piston 200 associated with at least one of the plurality of wheel brakes 180. The pump piston 200 is driven by an eccentric bearing (not shown) on the shaft of a pump motor 202 (different from the motor 190 included in the master cylinder 182), and the pump motor 202 transfers rotational motion to each pump piston 200 to selectively supply pressurized hydraulic fluid to an isolation / relief control valve device of at least one wheel brake 180 associated with the pump piston 200. Figure 10 Shown: one pump piston 200 is associated with two wheel brakes 180, and there are a total of two pump pistons 200 in the brake system 178. The pump piston 200 and the pump motor 202 together can be considered to constitute the secondary brake module (also referred to as the "secondary power transmission unit") of the brake system 178. For example, the two pump pistons 200 shown in the figure can supply pressurized hydraulic fluid to the corresponding wheel brakes 180 via corresponding isolation / relief control valve devices (when present) at the first pump outlet 196 and the second pump outlet 198, respectively, to actuate a first pair of wheel brakes 180 and a second pair of wheel brakes 180 in at least one of a normal non-fault braking mode and a standby braking mode. Each of the first pump outlet 196 and the second pump outlet 198 can supply fluid to a corresponding pair of the first pair of wheel brakes 180 and the second pair of wheel brakes 180. It is contemplated that in some configurations of the brake system 178, a plurality of pump pistons 200 can be associated with each of the first pump outlet 196 and the second pump outlet 198.

[0052] The secondary brake module of the braking system 178 can be used as a pressure source to provide a desired pressure level to those selected wheel brakes 180 in a standby or "fault" situation where, for some reason, the master cylinder 182 cannot supply fluid to the selected wheel brakes 180. Thus, the secondary brake module can be directly fluidly connected to the reservoir 186 for exchanging hydraulic fluid between these components without having to route the fluid through the motor-driven master cylinder 182 (which may fail) or another structure of the braking system 178.

[0053] The secondary brake module can be used to selectively supply hydraulic fluid to at least one wheel brake 180 not only in a standby braking mode but also in an enhanced braking mode, which can occur independently and / or concurrently with the standby braking mode or a normal non-fault braking mode. Examples of suitable enhanced braking mode functions that can be used in the braking system 178 can include, but are not limited to, "overboost" (where a higher pressure than that normally obtainable from the master cylinder 182 alone is supplied to a particular brake) and "volume-add" (where more fluid than that normally obtainable from the master cylinder 182 is supplied to a particular brake). In some operating environments, these enhanced braking modes can be facilitated by one or more pump pistons 200. For example, in at least one of the normal non-fault braking mode and the standby braking mode, the secondary brake module can then supply pressurized (higher than the pressure obtained from the master cylinder 182) hydraulic fluid to at least one of the first pump output 196 and the second pump output 198.

[0054] Figure 10The illustrated brake system 178 also includes at least one electronic control unit (“ECU”) 210 for controlling at least one of the master cylinder 182 and the secondary brake module (via the pump motor 202) in response to at least one brake pressure signal, where a first ECU 210A and a second ECU 210B are shown and described herein. The ECUs 210A, 210B may include a microprocessor and other circuitry. The ECUs 210A, 210B receive various signals in a wired and / or wireless manner, process the signals and control the operation of various electrical components of the corresponding brake system 178 in response to the received signals. The ECUs 210A, 210B may be connected to various sensors such as a reservoir level sensor 188, pressure sensors, travel sensors, switches, wheel speed sensors, and steering angle sensors. The ECUs 210A, 210B may also be connected to an external module (not shown) for receiving information related to the yaw rate, lateral acceleration, longitudinal acceleration of the vehicle or other characteristics of the vehicle operation for any reason, the vehicle operation such as but not limited to controlling the brake system 178 during vehicle braking, stability operation or other operation modes. Additionally, the ECUs 210A, 210B may be connected to an instrument cluster for collecting and providing information related to warning indicators such as an ABS warning light, a brake level warning light, and a traction control / vehicle stability control indicator light. It is contemplated that at least one of the ECUs 210A and 210B may be integrated, for example, with the master cylinder 182 or the pump motor 202.

[0055] The first ECU 210A and the second ECU 210B may divide the control tasks for the brake system 178 in any desired manner and may be readily configured by one of ordinary skill in the art for a particular use environment of the brake system, but it is contemplated that any control task performed by one or more of the ECUs 210 will be accomplished in response to at least one brake pressure signal and / or a brake signal generated by the deceleration signal transmitter 184. For example, the first ECU 210A is operable to control the motor 190 of the master cylinder 182. The second ECU 210B is operable to control the pump motor 202 and potentially, as will now be discussed, control at least one of the isolation / dump control valve means and at least one of the first traction control isolation valve and the second traction control isolation valve.

[0056] Figure 10An isolation / relief control valve device is shown associated with each of a plurality of wheel brakes 180. Each isolation / relief control valve device includes an isolation valve 212 and a relief valve 214 for providing a desired fluid path to the associated wheel brake 180. A reservoir 186 is hydraulically connected to the master cylinder 182 and hydraulically connected to each isolation / relief control valve device, for example, via a return line 216. Each isolation / relief control valve device includes an isolation valve 212 and a relief valve 214 arranged in series therewith. For a corresponding wheel brake 180, the normally open isolation valve 212 for each isolation / relief control valve device is hydraulically located between the respective wheel brake 180 and the master cylinder 182, and the normally closed relief valve 214 for each isolation / relief control valve device is hydraulically located between the respective wheel brake 180 and the reservoir 186.

[0057] The isolation / relief control valve device can selectively provide slip control to at least one wheel brake 180 powered by the master cylinder 182 and / or the aforementioned secondary brake module. More generally, the isolation / relief control valve device and / or other valves of the brake system 178 (any of which can be solenoid-operated and have any suitable configuration) can be used to help provide a controlled braking operation, such as but not limited to ABS, traction control, vehicle stability control, dynamic rear proportioning, regenerative braking hybrid, and autonomous braking.

[0058] A first traction control isolation valve 218 is hydraulically placed between the master cylinder 182 and at least one isolation / dump control valve device via a first MC output 192. A second traction control isolation valve 220 is hydraulically placed between the master cylinder 182 and at least one isolation / dump control valve device via a second MC output 194. As Figure 10 shown, it is contemplated that the isolation / relief control valve device can be associated with each of a first pair of wheel brakes and a second pair of wheel brakes 180. The first traction control isolation valve 218 is hydraulically placed between the motor-driven master cylinder 182 and the isolation / dump control valve device of the first pair of wheel brakes 180. Similarly, the second traction control isolation valve 220 is hydraulically placed between the motor-driven master cylinder 182 and the isolation / dump control valve device of the second pair of wheel brakes 180.

[0059] It can be seen that Figure 10Each isolation / relief control valve device in the braking system 178 is in direct or indirect fluid communication with a selected one of the first MC output 192 and the second MC output 194 and a selected one of the first pump output 196 and the second pump output 198, for selectively receiving pressurized hydraulic fluid from the output(s) during different braking modes or as needed. A person of ordinary skill in the art will be able to readily configure the braking system 178 for any particular use application as needed.

[0060] The brake pressure signal is at least one input that the ECU 210 can consider and in response control one or more other components of the braking system 178 to achieve the desired braking result for a particular use environment. One potential source of the brake pressure signal is a brake pressure sensor. For example, as shown, the braking system 178 can include at least one (e.g., at least two) brake pressure sensors 222. As Figure 10 shown, the first brake pressure sensor 222A can be hydraulically positioned between a selected isolation / relief control valve device and the corresponding rear brake in a selected one of the first pair of wheel brakes 180 and the second pair of wheel brakes 180, and the second brake pressure sensor 222B can be hydraulically positioned between another isolation / relief control valve device and the corresponding rear brake in another one of the first pair of wheel brakes 180 and the second pair of wheel brakes 180. Together with or instead of the first brake pressure sensor 222A and the second brake pressure sensor 222B, a third brake pressure sensor 222C can be hydraulically positioned between the first traction control isolation valve 218 and the master cylinder 182, and / or a fourth brake pressure sensor 222D can be hydraulically positioned between the second traction control isolation valve 220 and the master cylinder 182. A person of ordinary skill in the art can readily provide the desired number / position / type of pressure sensors 222 for a particular braking system 178.

[0061] In Figure 10In the braking system 178, a single return line 216 places the reservoir 186 and each pump piston 200 in hydraulic connection. The braking system 178 also includes a pump inlet attenuator 224 that is hydraulically placed between the reservoir 186 and the pump piston 200 to "smooth" the fluid flow between the reservoir 186 and the pump piston 200. The pump inlet attenuator 224 is in direct fluid connection with the reservoir 186 via the single return line 216 and adjusts the pressure in the single return line 216 to reduce the pressure fluctuations on the inlet side of each pump piston 200 via only mechanical pressure attenuation. At least a portion of the pump inlet attenuator 224 may be in fluid communication with the surrounding space external to the braking system 178 as needed. The pump inlet attenuator 224 may be the single pump inlet attenuator 224 as shown and discussed herein, or it is contemplated that multiple pump inlet attenuators (not shown) may be provided for certain operating environments of the braking system 178.

[0062] Known braking systems require the fluid column in the return line 216 to accelerate and decelerate due to the flow fluctuations generated at the inlet of the pump piston 200. This results in undesirable pressure fluctuations and reduced pump volumetric efficiency. In contrast, the presence of the pump inlet attenuator 224 promotes improved pump build rate performance with a smaller diameter and / or longer return line 216. The pump inlet attenuator 224 (also referred to as a "pump inlet damper") may be encapsulated within the return line 216 (e.g., in a reservoir hose adapter of the braking system 178) or "piggybacked" on the housing structure of another component (e.g., a secondary brake module). Since the pump piston 200 of the braking system 178 withdraws relatively low-pressure fluid from the return line 216 (within which the pump inlet attenuator 224 is embedded), the pump inlet attenuator 224 does not need to be able to withstand the relatively high pressure generated in the conduit from the master cylinder 182. Thus, the pump inlet attenuator 224 can serve two / all pump pistons 200 while still having relatively inexpensive (e.g., molded plastic) components since the pump inlet attenuator 224 operates in a low-pressure environment as shown.

[0063] In contrast, and as previously mentioned, Figures 1 to 9 The accumulator assembly 100 shown in can be used at least in a medium-pressure environment. To this end, the first accumulator assembly 100A is hydraulically placed between the first MC output 192 and at least one of the first pair of wheel brakes 180. The second accumulator assembly 100B is hydraulically placed between the second MC output 194 and at least one of the second pair of wheel brakes 180. For example, as Figure 10As shown, in the case of constructing the customized braking system 178, both the first accumulator assembly 100A and the second accumulator assembly 100B are configured to supply pressurized hydraulic fluid to the corresponding front wheel brakes 180 faster than the motor-driven master cylinder 182 or the secondary brake module can supply pressurized hydraulic fluid to the corresponding front wheel brakes 180. This can be helpful, for example, during "peak application" situations or other rapid response commands from the user (e.g., "stomping" on the brakes when rapid vehicle stopping is desired), especially when there is a running clearance between the brake pads and the rotor that is desired to be rapidly absorbed.

[0064] The first accumulator assembly 100A and the second accumulator assembly 100B can also each facilitate the power-off discharge / charging phase of the life operation of the braking system, as previously mentioned, which can contribute to the effective and convenient assembly / manufacture of the vehicle. It is also envisioned that the first accumulator assembly 100A and the second accumulator assembly 100B can contribute to the refilling of the medium-pressure accumulator 102 without applying pressure to the corresponding wheel brakes, but only using "pass-through" fluid directly from one or more sources of pressurized hydraulic fluid (e.g., the motor-driven master cylinder 182 and / or the secondary brake module). Additionally, the design of the MPA check valve 106 provides a simpler (and thus potentially less expensive) valve assembly than prior art solutions that require allowing two-way fluid in and out of the accumulator.

[0065] Referring again to Figure 10 , the reservoir 186 and the motor-driven master cylinder 182 can be co-located in a first housing (schematically indicated by the dashed line "1" in these figures), and the secondary brake module can be located in a second housing spaced apart from the first housing (schematically indicated by the dashed line "2" in these figures). Optionally, as also Figure 10 shown, the isolation / relief control valve device, the first accumulator assembly 100A and the second accumulator assembly 100B, and / or the first traction control isolation valve 218 and the second traction control isolation valve 220 can also be located in the second housing.

[0066] The first housing and the second housing (and the included / collocated components) of any braking system 178 can be provided and configured by those of ordinary skill in the art based on factors including, but not limited to: achieving a desired result in at least one aspect of design, manufacture, repair, space utilization in the vehicle, cost, size, regulatory compliance, etc.

[0067] Figures 11 to 12 An exemplary arrangement of the second housing of the braking system 178 according to the previously described is schematically shown from the relative front / rear side. In Figures 11 to 12 it, the block housing 108 is shown as a rectangular prism (labeled "2" to correspond toFigure 10 a marking), wherein the bore or cavity is machined or otherwise produced for use in or fluid connection to the marked component. As is visible in Figures 11 to 12 , for example, the block housing 108 is similar to known block housings for other braking systems having a low-pressure accumulator and associated supply valve, but wherein the medium-pressure accumulator 102 and the MPA check valve 106 of the accumulator assembly 100 replace these components, respectively. This facilitates easy design, manufacture, procurement, assembly, or facilitates the transition between using a known block housing (for a prior art braking system) and the block housing 108 associated with the present braking system 178. A person of ordinary skill in the art can readily provide a block housing 108 configured to suit the required packaging configuration for a particular use environment.

[0068] It is envisioned that a person of ordinary skill in the art can provide various other components in the braking system 178 described herein, such as a service brake motor and / or a parking brake motor, to achieve a desired configuration for a particular use environment. For example, although multiple filters and pressure sensors or other sensors are shown in the drawings, specific descriptions thereof are omitted herein for the sake of brevity, because a person of ordinary skill in the art will readily understand how to provide the desired quantity, arrangement, and / or operation of filters, sensors, and any other components according to the needs of the particular use environment of the present invention.

[0069] It is envisioned that although various components are schematically shown in certain arrangements in the drawings, these components may not achieve the exact relative configuration shown, depending on the operating conditions in a particular use environment. For example, the lift valve may not reciprocate to completely block the associated valve seat. However, a person of ordinary skill in the art will understand which potential other positions can substantially produce the desired results for a particular use environment. A person of ordinary skill in the art can configure the various orifice sizes, fluid paths, hydraulic channels, and other components of the accumulator assembly 100 to achieve the desired operating characteristics of the accumulator assembly 100 in a particular use environment.

[0070] As used herein, the singular forms "a", "an", and "the" may also include the plural forms, unless the context clearly dictates otherwise. It should also be understood that the terms "comprises" and / or "comprising" as used herein may specify the presence of the stated features, steps, operations, elements, and / or components, but do not preclude the presence or addition of one or more other features, steps, operations, elements, components, and / or combinations thereof.

[0071] As used herein, the term "and / or" may include any and all combinations of one or more of the associated listed items.

[0072] It should be understood that when an element is referred to as being "on another element", "attached to another element", "connected to another element", "coupled with another element", "in contact with another element", "adjacent to another element", etc., the element can be directly on, attached to, connected to, coupled with, in contact with, or adjacent to the other element, or there may also be intervening elements. In contrast, when an element is referred to as, for example, "directly on another element", "directly attached" to another element, "directly connected" to another element, "directly coupled" with another element, "directly in contact" with another element, or "directly adjacent" to another element, there are no intervening elements. Those of ordinary skill in the art will also understand that a reference to a structure or feature "directly adjacent" to another feature may have portions that overlap or are located beneath the adjacent feature, while a structure or feature "adjacent" to another feature may not have overlapping or underlying portions.

[0073] Spatially relative terms, such as "under", "beneath", "lower", "above", "upper", "proximal", "distal", etc., may be used herein for ease of description to describe the relationship of one element or feature to another element or feature as shown in the figures. It should be understood that, in addition to the orientations shown in the figures, spatially relative terms may also encompass different orientations of the device during use or operation. For example, if the device in the figures is inverted, an element described as "under" or "beneath" another element or feature will be oriented "above" the other element or feature.

[0074] As used herein, the phrase "at least one of X and Y" can be interpreted to include: 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, the element can include, at a particular time: X; Y; or a combination of X and Y, and the selection can vary over time. In contrast, the phrase "at least one of X" can be interpreted to include one or more of X.

[0075] It should be understood that although the terms "first", "second", etc. may be used herein to describe various elements, these elements are not limited by these terms. These terms are only used to distinguish one element from another. Thus, the "first" element discussed below could also be referred to as the "second" element without departing from the teachings of the present disclosure. The order of operations (or steps) is not limited to the order given in the claims or the figures, unless specifically stated otherwise.

[0076] While aspects of the present disclosure have been specifically shown and described with reference to the example aspects above, those of ordinary skill in the art will understand that various additional aspects can be envisioned. For example, the specific methods of using the apparatus described above are merely illustrative; those of ordinary skill in the art can readily determine any number of tools, sequences of steps, or other ways / options for placing the apparatus or its components into positions that are substantially similar to those shown and described herein. To maintain clarity in the drawings, some repeated components are not specifically numbered, but those of ordinary skill in the art will recognize the element numbers associated with the unnumbered components based on the numbered components; the presence or absence of element numbers in the drawings is not intended or suggestive of a distinction between similar components. Any described structure and components can be formed integrally as a single unit or monolith, or be composed of separate sub-components, any of these configurations including any suitable raw materials or custom components and / or any suitable materials or combinations of materials. Depending on the needs of a particular use environment, any described structure and components can be disposable or reusable. Any component can have user-perceivable markings to indicate materials, configurations, at least one dimension, etc. related to the component, and the user-perceivable markings potentially assist the user in selecting one component from an array of similar components for a particular use environment. A "predetermined" state can be determined at any time before the structure being manipulated actually reaches that state, and "predetermined" occurs shortly before the structure reaches the predetermined state. The term "substantially" is used herein to mean to a large extent (but not necessarily entirely) the specified quality - a "substantially" quality allows for some relatively minor inclusion of non-quality items. While some components described herein are shown as having specific geometries, all structures of the present disclosure can have any suitable shape, size, configuration, relative relationship, cross-sectional area, or any other physical characteristics desired for a particular application. Any structure or feature described with reference to one aspect or configuration can be provided alone or in combination with other structures or features to any other aspect or configuration, as it would be impractical to describe each aspect and configuration discussed herein as having all options discussed with respect to all other aspects and configurations. An apparatus or method incorporating any of these features should be understood to fall within the scope of the present disclosure as determined based on the following claims and any equivalents thereof.

[0077] Other aspects, objects, and advantages can be obtained by studying the drawings, the disclosure, and the appended claims.

[0078] Related Applications

[0079] This application relates to technologies disclosed in one or more of the following applications: U.S. Provisional Patent Application No. 63 / 580,042 (Attorney Docket No. 301699-US-PSP), filed on September 1, 2023, with the invention title "Brake System with Electric Motor-Driven Master Cylinder and Low-Pressure Accumulator"; U.S. Provisional Patent Application No. 63 / 580,048 (Attorney Docket No. 301647-US-PSP), filed on September 1, 2023, with the invention title "Brake System with Electric Motor-Driven Master Cylinder and Pump Inlet Attenuator"; U.S. Patent Application No. 18 / 474,714 (Attorney Docket No. 301647-US-NP), filed on September 26, 2023, with the invention title "Brake System with Electric Motor-Driven Master Cylinder and Pump Inlet Attenuator"; U.S. Patent Application No. 18 / 474,657 (Attorney Docket No. 301158-US-NP), filed on September 26, 2023, with the invention title "Brake System with Electric Motor-Driven Master Cylinder and Bypass Valve"; and U.S. Patent Application No. 18 / 474,678 (Attorney Docket No. 301699-US-NP), filed on September 26, 2023, with the invention title "Brake System with Electric Motor-Driven Master Cylinder and Low-Pressure Accumulator"; for various purposes, the entire contents of all these applications are incorporated herein by reference.

Claims

1. An accumulator assembly, comprising: The medium pressure accumulator is MPA, which includes: an MPA chamber including at least one brake-side passage adjacent a first end of the MPA chamber and including at least one pump-side passage adjacent a first end of the MPA chamber; an MPA piston for reciprocating longitudinal movement within the MPA chamber in response to a predetermined amount of hydraulic fluid flowing through at least one of the pump-side passage and the brake-side passage; and an MPA biasing spring for urging the MPA piston toward a first end of the MPA chamber; an unpowered MPA fill valve fluidly disposed between a pump-side passage of the MPA chamber and a source of pressurized hydraulic fluid, the MPA fill valve comprising: an MPA fill valve chamber that selectively fluidly connects a pump-side passage of the MPA chamber and the source of pressurized hydraulic fluid via an MPA fill valve fluid path; an MPA fill valve seat positioned along the MPA fill valve fluid path and at least partially defined by an inner wall of the MPA fill valve cavity; an MPA fill valve poppet configured to reciprocate between a poppet rest position and a poppet closed position in which an MPA fill valve poppet shoulder contacts the MPA fill valve seat to block fluid flow along the MPA fill valve fluid path past the MPA fill valve seat; and an MPA fill valve biasing spring that urges the MPA fill valve poppet toward the poppet closed position, the MPA fill valve poppet selectively reciprocating in response to at least one of a fluid pressure differential between the source of pressurized hydraulic fluid and the MPA chamber and a biasing force from the MPA fill valve biasing spring; and a power MPA check valve fluidly disposed between the brake-side passage of the MPA chamber and at least one corresponding wheel brake, the MPA check valve comprising: an MPA check valve chamber that selectively fluidly connects a brake-side passage of the MPA chamber and the at least one corresponding wheel brake via an MPA check valve fluid path; an MPA check valve seat located along the MPA check valve fluid path and defined by an inner wall of the MPA check valve cavity, An MPA check valve lift valve is configured to reciprocate between a check valve lift valve open position and a check valve lift valve closed position, in which the MPA check valve lift valve shoulder selectively contacts the MPA check valve seat to block fluid flow along the MPA check valve fluid path through the MPA check valve seat, and the reciprocating movement of the MPA check valve lift valve occurs at least partially in response to a predetermined amount of fluid pressure differential between the MPA chamber and at least one corresponding wheel brake.

2. The accumulator assembly according to claim 1, wherein: The source of pressurized hydraulic fluid is at least one of a master cylinder and a pump piston of a secondary brake module.

3. The accumulator assembly according to claim 1, wherein: The MPA fill valve cavity includes an annular groove adjacent a pump side passage of the MPA cavity, the annular groove being configured to retain an oriented MPA lip seal therein, the MPA lip seal selectively allowing hydraulic fluid flow along the MPA fill valve fluid path toward the MPA cavity past the MPA lip seal.

4. The accumulator assembly according to claim 3, wherein: The MPA lip seal selectively permits air flow past the MPA lip seal along the MPA charge valve fluid path toward the source of pressurized hydraulic fluid to provide an MPA drain port function during an unpowered drain / charge phase of life operation of the accumulator assembly.

5. The accumulator assembly according to claim 4, wherein: The MPA fill valve poppet includes an MPA bypass shoulder spaced apart from the MPA fill valve poppet shoulder, the MPA bypass shoulder selectively contacting an inner surface of the MPA lip seal to block gas flow along the MPA fill valve fluid path past the MPA lip seal toward the source of pressurized hydraulic fluid.

6. The accumulator assembly according to claim 5, wherein: In response to the MPA cavity containing a predetermined fill amount of hydraulic fluid, the MPA fill valve poppet extends through the pump-side passage and is at least partially retained within the MPA cavity with the MPA bypass shoulder making blocking contact with an inner surface of the MPA lip seal.

7. The accumulator assembly according to claim 6, wherein: When the MPA chamber includes the predetermined fill amount of hydraulic fluid and at least one corresponding wheel brake is applied, at least a first length of the MPA fill valve lift valve is located within the MPA chamber; the MPA fill valve lift valve selectively reciprocates within the MPA fill valve chamber in response to at least one of a fluid pressure differential between the pressurized hydraulic fluid source and the MPA chamber and a biasing force from the MPA valve biasing spring; and at least when the MPA chamber includes the predetermined fill amount of hydraulic fluid, a second length of the MPA fill valve lift valve is located within the MPA chamber, the second length of the MPA fill valve lift valve being less than the first length of the MPA fill valve lift valve.

8. The accumulator assembly according to claim 1, wherein: The MPA check valve includes an armature for selective longitudinal reciprocation relative to the MPA check valve chamber between a first armature position and a second armature position, wherein, in response to the armature being in the first armature position, the MPA check valve poppet is maintained in engagement with the MPA check valve seat in the check valve poppet closed position, and wherein, in response to the armature being in the second armature position, the MPA check valve poppet is permitted to selectively reciprocate between the check valve poppet closed position and the check valve poppet open position.

9. The accumulator assembly of claim 8, comprising a core for selectively magnetically attracting the armature, the core being longitudinally positioned directly adjacent to a core actuating surface of the armature, the armature being longitudinally disposed between the core and the MPA check valve poppet, the core being selectively energized to magnetically drive the armature between the first armature position and the second armature position.

10. The accumulator assembly of claim 8, comprising a poppet spring that biases the MPA check valve poppet toward the check valve poppet closed position and biases the MPA check valve poppet shoulder toward sealing engagement with the MPA check valve seat when the armature is in the second armature position.

11. The accumulator assembly according to claim 9, wherein: A core sleeve is at least partially housed in a housing that also at least partially defines the MPA cavity, the core sleeve being configured to maintain the core in a spaced relationship with the armature, the armature being at least partially enclosed in the core sleeve and being guided by the core sleeve for selective longitudinal reciprocating motion relative to the core in response to energization of the core.

12. The accumulator assembly of claim 9, comprising an iron core spring biasing the armature toward the MPA check valve poppet.

13. The accumulator assembly according to claim 11, wherein: The core sleeve completely surrounds the MPA one-way valve poppet and has a sleeve shoulder with reduced diameter, which is located on the end of the MPA one-way valve poppet opposite to the core. The sleeve shoulder at least partially defines the MPA one-way valve seat by including at least a portion of the inner wall of the MPA one-way valve cavity.

14. The accumulator assembly of claim 1, wherein: Reciprocating movement of the MPA check valve poppet occurs at least in part in response to fluid pressure in the MPA chamber being greater than a predetermined wheel-side fluid pressure.

15. A braking system for actuating a plurality of wheel brakes including a first pair of wheel brakes and a second pair of wheel brakes, the braking system comprising: Storage; a motor-driven master cylinder, or MC, operable during a normal, non-fault braking mode by actuation of an electric motor of said master cylinder to generate brake actuation pressures at a first MC output and a second MC output for hydraulically actuating said first pair of wheel brakes and said second pair of wheel brakes, respectively; a secondary brake module configured to selectively provide pressurized hydraulic fluid at a first pump output and a second pump output to actuate the first pair of wheel brakes and the second pair of wheel brakes in at least one of a normal non-fault braking mode and a backup braking mode, the secondary brake module including a pump 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 pump output and the second pump output, each of the first pump output and the second pump output providing fluid to a corresponding one of the first pair of wheel brakes and the second pair of wheel brakes; a first accumulator assembly and a second accumulator assembly, wherein each accumulator assembly is hydraulically interposed between a corresponding first MC output or a second MC output and at least one wheel brake of a corresponding first pair of wheels or a second pair of wheels, each of the first accumulator assembly and the second accumulator assembly comprising: a medium pressure accumulator; a non-powered MPA filling valve, the non-powered MPA filling valve being fluidly interposed between a pump side passage of the medium pressure accumulator and a source of pressurized hydraulic fluid; and a powered MPA check valve, the powered MPA check valve being fluidly interposed between a brake side passage of the medium pressure accumulator and the corresponding at least one wheel brake; and an electronic control unit for controlling at least one of the secondary brake module and the master cylinder in response to at least one brake signal; Wherein, the first accumulator assembly and the second accumulator assembly both facilitate an unpowered expulsion / fill phase of life operation of the braking system.

16. The brake system of claim 15, including a pump inlet attenuator hydraulically interposed between the reservoir and the pump piston and directly fluidly connected to the reservoir via a single return line.

17. The brake system of claim 15, comprising an isolation / pressure relief control valve device associated with each of the plurality of wheel brakes, each isolation / pressure relief control valve device being controlled by the electronic control unit, and a selected one of the first accumulator assembly and the second accumulator assembly being hydraulically disposed between a corresponding one of the first MC output end and the second MC output end and at least one associated isolation / pressure relief control valve device.

18. The brake system according to claim 17, wherein: The reciprocating movement of the MPA filling valve poppet occurs at least in part in response to at least one of: the application state of at least one associated wheel brake; the relative pressures within the MPA chamber and at least one other component of the accumulator assembly; and the operation of at least one associated isolation valve of the isolation / valve control valve device.

19. The brake system according to claim 15, comprising: a first traction control isolation valve hydraulically interposed between the motor-driven master cylinder and the first accumulator assembly via the first MC output; as well as A second traction control isolation valve is hydraulically interposed between the motor-driven master cylinder and the second accumulator assembly via the second MC output.

20. The braking system according to claim 15, wherein: A first brake pressure sensor is hydraulically disposed between a selected isolation / dump control valve device and a corresponding rear brake in a selected pair of the first pair of wheel brakes and the second pair of wheel brakes, and a second brake pressure sensor is hydraulically disposed between another isolation / dump control valve device and a corresponding rear brake in the other pair of the first pair of wheel brakes and the second pair of wheel brakes.

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