Apparatus for increasing brake cylinder pressure by controlling pump motor and reducing the pressure by controlling electric energy applied to control valve

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a soleooid-operated pressure control valve disposed between said low-pressure aource and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling an amount of electric energy to be applied to said electric motor while said pump is held in communication with said brake cylinder, such that said amount of electric energy to be applied to said electric motor corresponds to an operating state of a manually operable brake operating member, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve;
• wherein said controller activates one of said pressure increase control means and said pressure reduction control means, depending on at least one of a pressure difference between an actual value and a target value of the fluid pressure in said brake cylinder and a rate of change of said target value.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling an amount of electric energy to be applied to said electric motor while said pump is held in communication with said brake cylinder, such that said amount of electric energy to be applied to said electric motor corresponds to an operating state of a manually operable brake operating member, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve,
• wherein said controller includes a motor start control device for applying a higher voltage to said electric motor when said electric motor is turned on, and holding said higher voltage applied to said electric motor while a predetermined condition is satisfied, said higher voltage being higher than a voltage to be applied to said electric motor after said predetermined condition is satisfied.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling an amount of electric energy to be applied to said electric motor while said pump is held in communication with said brake cylinder, such that said amount of electric energy to be applied to said electric motor corresponds to an operating state of a manually operable brake operating member, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said controller includes pressure increase commanding means for commanding an increase in the fluid pressure in said brake cylinder when a predetermined pressure increase condition is satisfied, and motor pre-starting means for turning on said electronic motor when said predetermined pressure increase condition is expected to be satisfied in the near future.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling an amount of electric energy to be applied to said electric motor while said pump is held in communication with said brake cylinder, such that said amount of electric energy to be applied to said electric motor corresponds to an operating state of a manually operable brake operating member, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein a plurality of brake cylinders are connected through respective branch passages to said pump device such that said plurality of brake cylinders are parallel with each other, and said solenoid-operate pressure control valve is provided in each of a plurality of pressure reducing passages respectively connecting said branch passages to said low-pressure source, said apparatus further comprising a flow resistor device provided in a portion of each of said branch passages which is located between said pump device and a point of connection thereof to a corresponding one of said pressure reducing passages.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve,
• wherein said pressure reduction control means includes means for turning off said electric motor when the pressure of the fluid in said brake cylinder is reduced.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said controller includes a motor control device for controlling said electric motor to produce a larger output torque when a rate of increase of a target value of the fluid pressure in said brake cylinder is higher than a predetermined threshold, than when said rate of increase is not higher than said predetermined threshold.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said controller includes pressure hold control means for turning off said electric motor and placing said solenoid-operated pressure control valve in a state for inhibiting a discharge flow of the fluid from said brake cylinder, when a rate of change of a target value of the fluid pressure in said brake cylinder is held within a predetermined range.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said controller includes pressure hold control means for turning off said electric motor and placing said solenoid-operated pressure control valve in a state for inhibiting a discharge flow of the fluid from said brake cylinder, when a predetermined condition is satisfied, and pressure holding condition relaxing means for changing said predetermined condition such that the predetermined condition is more relaxed when said pressure hold control means is in operation for a relatively long time than when said pressure hold control means is in operation for a relatively short time.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said brake cylinder is activated to brake a wheel of an automotive vehicle, and said controller includes pressure hold control means for turning off said electric motor and placing said solenoid-operated pressure control valve in a state for inhibiting a discharge flow of the fluid from said brake cylinder, when a predetermined condition is satisfied, and pressure holding condition relaxing means for changing said predetermined condition such that the predetermined condition is more relaxed when said automotive vehicle is stationary than when said automotive vehicle is running.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said brake cylinder is activated to brake a wheel of an automotive vehicle, and said controller includes:
• pressure increasing means for increasing the fluid pressure in said brake cylinder by controlling said electric motor of said pump device while a predetermined pressure increasing condition is satisfied;
• compulsory pressure holding means for holding the fluid pressure in said brake cylinder by holding said electric motor off and placing said solenoid-operated pressure control valve in a state for inhibiting a discharge flow of the fluid from the brake cylinder, after a rotating speed of said wheel has been once substantially zeroed, even while said predetermined pressure increasing condition is satisfied;
• and
• disabling means for disabling said compulsory pressure holding means to operate, when the rotating speed of the wheel has exceeded a predetermined threshold and when an amount of operation of a brake operating member has been increased while said compulsory pressure holding means is operating.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve,
• wherein said controller includes pressure increase commanding means for commanding an increase in the fluid pressure in said brake cylinder when a predetermined pressure increase condition is satisfied, motor pre-starting means for turning on said electric motor when said predetermined pressure increase condition is expected to be satisfied in the near future, and
• wherein said brake cylinder is activated to brake a wheel of an automotive vehicle, said apparatus further comprising a downhill running detector for detecting that the automotive vehicle is running downhill, if an actual acceleration value of the vehicle is higher than an estimated acceleration value of the vehicle which is obtained on the basis of a vehicle drive torque produced by a drive power source for driving the vehicle, and wherein said motor pre-starting means including means for turning on said electric motor when at least one sign indicating a high possibility that said predetermined pressure increase condition will be satisfied in the near future is detected, said at least one sign including detection by said downhill running detector that the automotive vehicle is running downhill.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein a plurality of brake cylinders are connected through respective branch passages to said pump device such that said plurality of brake cylinders are parallel with each other, and said solenoid-operated pressure control valve is provided in each of a plurality of pressure reducing passages respectively connecting said branch passages to said low-pressure source, said apparatus further comprising a pump cut-off valve provided in a portion of each of said branch passages which is located between said pump device and a point of connection thereof to a corresponding one of said pressure reducing passages, said pump cut-off valve having a flow permitting stage for permitting a flow of the pressurized fluid delivered from said pump into a corresponding one of said brake cylinders, and a flow inhibiting state for inhibiting the flow of the pressurized fluid into said corresponding one of said brake cylinders, said controller including pump cut-off valve control means for placing said pump cut-off valve in said flow inhibiting state when a rate of reduction of a target value of the fluid pressure in each of at least one of said plurality of brake cylinders is higher than a predetermined pressure reduction threshold while a rate of change of said target value of the fluid pressure in each of the other of said brake cylinders is on the side of increasing the fluid pressure as compared with said predetermined pressure reduction threshold.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling said electric motor, and pressure reduction control means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve, wherein said pump device includes a low-pressure pump and a high-pressure pump having a higher delivery pressure and a lower delivery flow rate than said low-pressure pump.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a pump device connected to said brake cylinder and including at least one set of a pump for pressurizing the fluid and delivering the pressurized fluid to said brake cylinder and an electric motor for operating said pump;
• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said low-pressure source and said brake cylinder and operated with an electric energy applied thereto, for controlling a pressure of the fluid in said brake cylinder depending upon an amount of said electric energy;
• and
• a controller including pressure increase control means for increasing the pressure of the fluid in said brake cylinder by controlling an amount of electric energy to be applied to said electric motor while said pump is held in communication with said brake cylinder, such that the pressure of the fluid in said brake cylinder substantially corresponds to the amount of electric energy to be applied to said electric motor, and pressure reduction means for reducing the pressure of the fluid in said brake cylinder by controlling the amount of said electric energy applied to said solenoid-operated pressure control valve.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said brake cylinder and said low-pressure source, and including a solenoid-operated seating valve having a valve seat, a valve member movable to be seated on and unseated from said valve seat, and an electromagnetic force generating device for generating an electromagnetic drive force corresponding to an amount of electric energy applied thereto, such that the electromagnetic drive force acts on said valve member in a first direction for moving said valve member to be seated on said valve seat, said seating valve being constructed such that a pressure difference force based on a difference between the fluid pressures in said low-pressure source and said brake cylinder acts on said valve member in a second direction opposite to said first direction;
• and
• a controller including electric energy control means for controlling the amount of electric energy to be applied to said electromagnetic force generating device, depending upon the fluid pressure in said brake cylinder, when said valve member of said seating valve is held seated on said valve seat,
• and wherein said electric energy control means control the amount of electric energy to be applied to said electromagnetic force generating device such that said electromagnetic drive force is larger that said pressure difference force by at least a predetermined margin value which is determined by at least a maximum velocity of increase in the fluid pressure at said solenoid-operated pressure control valve.

A hydraulic pressure control apparatus for controlling a pressure of a working fluid in a brake cylinder, said apparatus comprising:

• a low-pressure source for storing the fluid discharged from said brake cylinder;
• a solenoid-operated pressure control valve disposed between said brake cylinder and said low-pressure source, and including a solenoid-operated seating valve having a valve seat, a valve member movable to be seated on and unseated from said valve seat, and an electromagnetic force generating device for generating an electromagnetic drive force corresponding to an amount of electric energy applied thereto, such that the electromagnetic drive force acts on said valve member in a first direction for moving said valve member to be seated on said valve seat, said seating valve being constructed such that a pressure difference force based on a difference between the fluid pressures in said low-pressure source and said brake cylinder acts on said valve member in a second direction opposite to said first direction;
• and
• a controller including slowly energy increasing means for slowly increasing, at a controlled rate, the amount of electric energy to be applied to said electromagnetic force generating device, when said valve member of said seating valve is seated on said valve seat.