Abstract: A valve body surrounds a first passage connecting with a cylinder of an engine. A valve member is adapted to be seated on and lifted from the valve seat. An injector body connects with the valve body. The injector body has a pressure control chamber for controlling hydraulic pressure applied to the valve member thereby controlling a lift of the valve member. The injector body has a second passage through which fuel in the pressure control chamber is exhausted. An actuator is adapted to communicating the pressure control chamber with the first passage through the second passage and blocking the pressure control chamber from the first passage. The first passage introduces fuel from the pressure control chamber into the cylinder through the second passage.

Abstract: A valve back pressure chamber is provided to exert a back pressure of a first valve needle. Furthermore, a hydraulic pressure passage is provided to extend through the valve back pressure chamber. A valve body is provided to a second valve needle and is driven to connect and disconnect between the hydraulic pressure passage and a fuel tank and thereby to drive the first valve needle. The second valve needle is driven by hydraulic pressure induced by an actuator.

Abstract: A three-way valve having a valve chamber with a low-pressure port, a high-pressure port, and a control port is provided. The three-way valve also has a control valve installed in the valve chamber for closing one of the low-pressure port and the high-pressure port. A guide hole communicates with the valve chamber via the high-pressure port. A guide portion is slidably installed in the guide hole and moves together with the control valve. The guide portion further receives a fuel pressure at the high-pressure port in a closing direction of the high-pressure port. The control valve is driven by a piezoelectric actuator to open the low-pressure port and close the high-pressure port. The valve chamber communicates with an oil-accumulating chamber via a by-pass conduit. The oil-accumulating chamber is defined within the guide hole and is located opposite the guide portion from the valve chamber.

Abstract: A valve actuating device is provided which may be employed in fuel injectors for automotive internal combustion engines. The valve actuating device includes an actuator, a large-diameter piston displaced by said actuator, a small-diameter piston operating a valve, a displacement amplifying chamber filled with working fluid to amplify and transmit displacement of the large-diameter piston to the small-diameter piston, and a drain passage. The drain passage communicates with the displacement amplifying chamber through a pinhole for draining the working fluid within the displacement amplifying chamber, thereby enabling the pressure in the displacement amplifying chamber to be released in order to ensure the movement of the small-diameter piston when the valve actuating device is started.

Abstract: A valve actuating device is provided which may be employed in fuel injectors for automotive internal combustion engines. The valve actuating device includes an actuator, a large-diameter piston displaced by said actuator, a small-diameter piston operating a valve, a displacement amplifying chamber filled with working fluid to amplify and transmit displacement of the large-diameter piston to the small-diameter piston, and a drain passage. The drain passage communicates with the displacement amplifying chamber through a pinhole for draining the working fluid within the displacement amplifying chamber, thereby enabling the pressure in the displacement amplifying chamber to be released in order to ensure the movement of the small-diameter piston when the valve actuating device is started.

Abstract: In a fuel infection valve, a valve chamber of a three ways valve is selectively communicated to drain and high pressure conduits and also communicated, via a main orifice, to a control chamber for controlling valve opening and closing operations of a nozzle needle. The control chamber may be communicated via the main orifice and the valve chamber to the drain conduit or the high pressure conduit, when a valve body is driven by a piezo actuator to open or close the drain conduit and close or open the high pressure conduit. The control chamber is always communicated via a sub orifice to the high pressure conduit without bypassing the three ways valve. Accordingly, hydraulic pressure in the control chamber is slowly decreased at a valve opening time and is rapidly increased at a valve closing time so that a lift characteristic of the nozzle needle is improved.

Abstract: Pressurized fuel of a common rail is introduced into a control chamber of a fuel injector. An electromagnetic valve opens or closes a fuel discharge passage of the control chamber to adjust a hydraulic pressure of the control chamber. Through a switching leak passage, bubble-containing fuel directly returns from a valve opening of the electromagnetic valve to a low-pressure return passage without passing through an armature chamber. Through a stationary leak passage, the fuel leaking from every slide portion returns to the return passage via the armature chamber. A downstream portion of the stationary leak passage opens to the upper portion of the armature chamber. A damper element is provided downstream of the electromagnetic valve in the return passage for canceling an increased fuel pressure.

Abstract: In an accumulator fuel injection device, a valve member of a solenoid valve includes a shaft and a spherical member. The spherical member is slidably supported at the tip portion of the shaft. The spherical member is prevented from falling off by caulking the tip of the shaft. A flat plate working as a valve seat for the spherical member is provided so that the spherical member allows communication between a pressure control chamber and a low-pressure side when separated from the flat plate, while prohibiting the communication therebetween when seated on the flat plate. On the other hand, the flat plate is formed with fuel relief passages in a tight contact region between the flat plate and the spherical member. The fuel relief passages communicate with the low-pressure side even when the spherical member is seated on the flat plate. Thus, a hydraulic force applied to the spherical member in a solenoid valve opening direction when the spherical member is seated on the flat plate, is rendered smaller.

Abstract: An accumulator fuel injection system for a diesel engine is provided which is designed to facilitates easy maintenance of an injector and may be used in different types of engines. The accumulator fuel injection system includes generally an injector, a solenoid valve for controlling injection timing, a connector supplying the power to the solenoid valve, a fuel supply pipe connection, and a fuel supply passage. The injector is installed in the engine to have an injector head disposed outside an engine head cover. The solenoid valve is disposed within the injector head eccentrically with the longitudinal center line of the injector. The connector is mounted on the injector head. The fuel supply connection is arranged opposite the injection nozzle across camshafts of exhaust and intake valves of the engine. The fuel supply passage is formed in a side wall of the injector head of said injector.

Abstract: A variable damping force shock absorber control system for an automotive vehicle is provided. This control system includes a variable damping force shock absorber adapted to have a plurality of damping modes of operation each assuming different damping characteristics, a vertical acceleration sensor for detecting vertical acceleration acting on a vehicle body, and a control unit. The control unit mathematically determines vertical speed of the vehicle body based on the vertical acceleration to select one of the damping modes based on the vertical speed, and determines the amount of damping force in each damping mode according to a vibratory condition indicative parameter which is varied as a function of a variation in amplitude of the vertical acceleration.

Abstract: A piezoelectric apparatus includes a piezoelectric device which is biased by a fluid force instead of a spring. Since the fluid force can be maintained within a predetermined value even after the piezoelectric device has been used number of times, and since the fluid force can be modulated by fluid pressure providing means and valve means when the fluid force is decreased from the predetermined valve, the present piezoelectric apparatus can maintain the initial pressure on the piezoelectric device.

Abstract: The expanding/contracting accelerations of shock absorbers on a motor vehicle are detected and compared with preset accelerations, respectively, by an electronic controller, which individually varies the damping forces of the shock absorbers as a result of the comparison. The electronic controller corrects the preset accelerations so that the damping forces of the shock absorbers will be switched over at a uniform frequency or the damping forces of the front left and rear left shock absorbers and the damping forces of the front right and rear right shock absorbers will be switched over at a constant frequency.

Abstract: A variable-damping-force shock absorber includes a piezoelectric actuator for producing a displacement, a hydraulic pressure chamber filled with a working oil and having a volume variable in response to the displacement produced by said piezoelectric actuator, and a plunger slidably disposed in a sleeve and reciprocally movable in response to a change in the volume of said hydraulic pressure chamber. The sleeve and said plunger define therebetween a gap communicating with said hydraulic pressure chamber. A supply passage for supplying a working oil from an external working oil source into said hydraulic pressure chamber extends through the gap. A leakage of the working oil from the hydraulic pressure chamber through the gap can automatically be compensated for by working oil supplied through the supply passage. Since the working oil leaks from and is supplied into the hydraulic pressure chamber through the gap, the leakage and supply of the working oil are kept in equilibrium.

Abstract: An auxiliary steering control system in connection with an anti-skid control system for use in a motor vehicle with two parts of left and right wheels, the anti-skid control system being adapted to independently control braking pressures for at least one pair of left and right wheels and including a braking actuator for adjusting braking pressures to be applied to the pair of left and right wheels. The braking actuator is controlled so that the braking pressures therefor approach the target braking forces determined on the basis of the rotational speeds of the wheels. The steering control device includes a steering actuator for adjusting steering angles of the pair of left and right wheels in response to steering control signals from a steering angle control unit.

Abstract: A stepping motor unit includes a stepping motor of the type wherein the interior of the stepping motor is filled with an oil, a detector for detecting the temperature of the oil in the stepping motor, a device for varying an upper limiting value of the rotational speed of the stepping motor and an upper limiting value of the rotational acceleration of the stepping motor in view of a current viscous condition of the oil based on the temperature detected by the temperature detector, and a driver for driving the stepping motor at a rotational speed and a rotational acceleration which fall in ranges, respectively, not exceeding the upper limiting values. The stepping motor unit thus constructed has rapid and accurate response characteristics and is capable of operating reliably without falling out of step even when the environmental temperature varies in a very wide range. A rotary control valve incorporating such stepping motor unit is also disclosed.

Abstract: A radial piston pump has a rotor provided within a cylinder chamber in such a manner that a center axis of the rotor is offset from a center axis of the cylinder chamber. The rotor has three working chambers a piston is slidably provided each of which. Each working chamber may connect with a suction groove or a discharge groove so that there exists a couple of situations, one of which is that two working chambers connect with the discharge chamber simultaneously and another one of which is that single working chamber connects with the discharge chamber. In order to make the forcing point at which total biassing force of the piston is focussed move gradually, the radial piston pump has a delay angle at a front side of the suction chamber. Namely a pressure within the working chamber is preliminary reduced before the working chamber connects to the suction groove so that the forcing point should shift gradually.

Abstract: The braking system comprising an input mechanism, such as a brake pedal or a brake lever, actuated by a vehicle operator during brake application. A sensor senses the pressure exerted on the brake pedal and delivers a first electrical signal in accordance with that pressure. The system also includes a source of brake fluid under a constant fluid pressure and pressure modulators in fluid communication with the source and the wheel cylinders. An electronic control unit responds to the first signal and delivers to the pressure modulators a second electrical signal proportional to the first signal to cause the pressure modulators to communicate to the wheel cylinders a fluid pressure proportional to the second signal to apply the brake with a braking force proportional to the applied pressure. The braking system also provides an anti-skid function, traction control function, and braking force proportioning function.

Abstract: The hydraulic cylinder mechanism has a main piston which has a piston portion, two sub-pistons which is so located that the sub-pistons can hold the piston portion, control pressure chambers which are formed between the sub-piston and the piston portion, and holding pressure chambers which are formed at behind of the sub-piston. The hydraulic cylinder mechanism controls automotive rear wheel alignment when the main piston moves axially according to the pressure in the control pressure chambers and can maintain its neutral position when the pressure in the holding chamber is applied to the sub-piston so that holds the piston portion.

Abstract: The device of this invention has a variable capacity pump, a channel through which the discharged fluid from the pump passes toward an actuator, a variable choke located in the channel and pressure detecting means which detects the pressure difference on opposite sides of the variable choke. The pump varies its volume in relation with the pressure difference detected by the pressure detecting means. The opening area of the channel is varied by the variable choke in relation with the pressure of the fluid being supplied to the actuator, namely the pressure of the fluid flowing downstream of the variable choke. The device of this invention may also have an auxiliary variable choke located in the channel. The auxiliary variable choke can control the amount of fluid being supplied to the actuator in response to the operating condition of the actuator.

Abstract: An improved power steering system for vehicles is utilized in association with a variable discharge pump for supplying pressure fluid to one of both cylinder chambers divided by a piston of a power cylinder, selectively. The power steering system includes a variable throttle provided in a fluid supplying passage between the pump and the cylinder chamber. Upon rotation of a steering shaft, an adjusting member adjusts a cross sectional area of the variable throttle in accordance with the variable steering torque. The power steering system also includes a discharge quantity controller for controlling a discharge quantity of the pressure fluid of the pump so that a pressure differential between up and downstreams of the variable throttle is constant. The discharge quantity of the pressure fluid of the pump is changed to be suitable to the any variable steering torque.