摘要:
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a flux tube having an end cap, a thick tube section, and a thin tube section defining an interior volume. An armature is slidably received in the interior volume of the flux tube. A coil is provided about the flux tube. A collar covers a portion of the thin tube section and is spaced from the thick tube section so that an air gap is provided between the coil and the portion of the thin tube section not covered by the collar.
摘要:
This invention relates to an electro-hydraulic brake-by-wire system including a hydraulic pump and a plurality of valves to achieve a demanded braking force, and to achieve a desired brake pedal feel. The brake system includes a plurality of wheel brakes, a reservoir of hydraulic fluid, and a pump for selectively pumping hydraulic fluid from the reservoir and supplying pressurized hydraulic fluid to the wheel brakes for applying a braking force. The pump acts as a source of pressurized hydraulic fluid to the wheel brakes during normal brake apply, as well as during advanced braking functions as Antilock Braking (ABS), Traction Control (TC), or Vehicle Stability Control (VSC). An apply valve is associated with each of the wheel brakes for selectively permitting flow of pressurized hydraulic fluid from the pump to the associated wheel brake. A dump valve is associated with each of the wheel brakes for selectively permitting flow of pressurized hydraulic fluid from the associated wheel brake to the reservoir. A master cylinder is operated by a brake pedal for pressurizing hydraulic fluid. An isolation valve is associated with each of the wheel brakes for selectively preventing flow of pressurized hydraulic fluid from the master cylinder to the associated wheel brake. A sensor senses the position of the brake pedal and generates a pedal position signal representative of the position of the brake pedal. An electronic control unit receives the pedal position signal, which signal is utilized to determine a brake demand. The electronic control unit controls the operation of the pump, and the apply, dump, and isolation valves associated with each wheel brake to achieve a desired braking force at each wheel brake based on the brake demand and to regulate pressure generated by the master cylinder to achieve a predetermined relationship between the pressure generated by the master cylinder and the position of the brake pedal, whereby a desired pedal feel is achieved.
摘要:
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a tube. A flux cap is pressed onto one end of the tube. A flux ring pole is pressed onto an opposite end of the tube. An armature is slidably received in the tube. A coil subassembly is provided about the tube, flux cap, and flux ring pole. A valve seat receives the flux ring pole. The valve seat is mounted in a bore of a hydraulic control unit of a vehicular brake system.
摘要:
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a valve seat. A sleeve is mounted on the valve seat. An armature core is slidably received in the sleeve. The armature core has a passage extending between first and second planar end surfaces of the armature core. An armature body is formed from a moldable material onto the armature core. The armature body has a central section received in the passage of the armature core, a first end section extending from the first end surface of the armature core, and a second end section extending from the second end surface of the armature core. This control valve is particularly adapted to be mounted in a bore of a housing of a hydraulic control unit of an electronically controlled vehicular brake system.
摘要:
An improved force transfer arrangement for use in a dual circuit master cylinder having a pair of nested concentric pistons for pressurizing a pair of respective fluid chambers, wherein the force transfer arrangement imparts an input force from an input piston on a pair of pistons such that the pair of pistons can move relative to each other to compensate for different travel lengths. The invention discloses three embodiments of the improved force transfer arrangement. A first embodiment includes a hydraulic fluid chamber in fluid communication with the input piston and the pair of pistons. A second embodiment includes a circumferentially arranged ball mechanism positioned between the input piston and the pair of pistons. A third embodiment includes a notched lever ring assembly positioned between the input piston and the pair of pistons.
摘要:
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a valve seat. A sleeve is mounted on the valve seat. An armature core is slidably received in the sleeve. The sleeve includes a first ferromagnetic portion adjacent the valve seat, a second ferromagnetic portion, and an annular region defining an area of increased magnetic reluctance. A part of the first portion of the sleeve defines a radial magnetic pole for the generally radial flow of magnetic flux from the armature to the sleeve. A portion of the valve seat adjacent the armature defines an axial magnetic pole for the generally axial flow of magnetic flux from the armature to the valve seat. Together, the generally radial flow of flux and the generally axial flow of flux generate a force urging the armature from an open position toward a closed position when the coil is energized.
摘要:
A control valve for controlling fluid flow in a hydraulic control unit of a vehicular brake system includes a valve body. A flux tube is mounted on the valve body. An armature core having first and second ends and a longitudinal passage is slidably received in the flux tube. A bearing element is formed from a low-friction material. The bearing element includes a stem received into the longitudinal passage and an end cap having a diameter greater than a diameter of the armature core.
摘要:
An improved compensation piston arrangement for use with a dual circuit master cylinder having a single service piston for simultaneously pressurizing a first fluid chamber and a second fluid chamber, wherein the compensation piston arrangement provides for pressure balancing between the first fluid chamber and the second fluid chamber to compensate for minor normal differences between the first and second fluid chamber. The compensation piston arrangement includes a movable compensation piston slidably disposed within a bore of a compensation housing, wherein the housing defines a pair of end stops positioned on opposing sides of the compensation piston. The bore is in fluid communication with the fluid chambers such that the pressure within the first fluid chamber acts on a first side of the compensation piston, and the pressure within the second fluid chamber acts on a second end of the compensation piston which is opposite the first end. The compensation housing can be incorporated within the service piston or can be remotely located from the master cylinder.
摘要:
A method for assembling a hydraulic control unit of a vehicular brake system includes the following steps of: providing a sleeve having a closed end; sliding a spring over an armature to form an armature/spring subassembly; orientating the armature subassembly to produce a normally open valve or a normally closed valve; sliding the oriented armature/spring subassembly into the sleeve; sliding a valve seat into the sleeve; crimping a portion of the sleeve onto the valve seat to form a sleeve/valve seat subassembly; inserting the sleeve/valve seat subassembly into a bore of a housing. Two additional steps can be combined with the above listed steps to provide a method of assembling the control valve subassemblies described above on a hydraulic control unit. The additional steps include: inserting the sleeve/valve seat subassembly into a bore in a housing; and pressing a coil assembly about the sleeve.
摘要:
A vehicle anti-lock brake system control unit having a control valve for a housing with a control valve bore therein. The control valve includes a sleeve with a moveable armature, and a coil surrounding the sleeve for moving the armature. The control valve also includes a valve body having an outer end attached to the sleeve and an inner end seated within the control valve bore of the housing. The valve body has an outer diameter no greater than the outer diameter of the coil such that minimum spacing between multiple control valves in the control unit is not limited by the outer diameter of the valve body.