Toyota Jidosha Kabushiki Kaisha

Nippondenso Co., Ltd.

Toyota Jidosha Kogyo Kabushiki Kaisha

Fumiaki Kobayashi

Yoshiyasu Ito

Hideo Miyagi

Masahiko Miyaki

Masaomi Nagase

Keisuke Tsukamoto

Kiyotaka Matsuno

Mamoru Kobashi

Takashi Hasegawa

Mikio Kizaki

Kazuo Shinoda

Hiroshi Koide

Mitsuru Ban

Mamoru Takata

Noritaka Ibuki

Takio Tani

Atsusi Taguchi

Yoshiyasu Itou

Nagase Masaomi

According to the present invention, when means is provided for correcting a shift in phase of an engine rotation pulse and a dispersion in responses of an electromagnetic spill valve, and a control signal to a fuel injection pump is corrected in response to an output from the correcting means, if abnormality of output from the correcting means is detected, then the control signal to the fuel injection pump is corrected by use of a fixed valve. As a consequence, even when the output from the correcting means is abnormal, neither excessively large nor excessively small correction is performed and the running at the lowest level can be made, preventing the diesel smoke from being deteriorated and the engine from being damaged.

Method and device for correcting a fuel injection quantity in a diesel

A fuel injection control system for internal combustion engine comprises a fuel injection pump including a plunger slidably reciprocating in synchronism with rotation of the engine and a spill port establishing communication between a low pressure chamber and a pump chamber. An electronic control unit is responsive to engine operating conditions for the determination of fuel injection time period and controls the solenoid-operated valve to close the spill port in response to the requirement of fuel injection into the cylinder and open the same to terminate the fuel injection. The fuel injection control system further comprises a circuit including two fixed resistors and two adjusting resistors so that first and second voltage signals are developed at its terminals. The two adjusting resistors respectively determine the value of the voltage signals. The first voltage signal is regulated to correspond to the response time lag inherent in the solenoid valve and the second voltage signal is regulated to correspond to the error of the generation timing of the detection signal of a reference plunger position detector. The correction of fuel injection time period is made on the basis of the first and second voltage signals. pg,4

Fuel injection control based on spill port opening timing correction

In controlling ignition timing in accordance with a deviation between a target ignition timing determined on the basis of at least an engine load and an engine speed and an actual ignition timing detected by use of an ignition timing sensor, when non-perfect explosion operating conditions, wherein an ignition signal is difficult to detect, or operating conditions in which the ignition signal is instable are present, an open loop control on the basis of the engine load and the engine speed is effected. Feedback control is effected when the ignition signal is detected with neither non-perfect explosion operating conditions nor instable ignition signal operating conditions being present. When the ignition signal is not detected, the aforesaid open loop control is effected and a trouble in the ignition timing sensor is detected.

Method of and system for controlling injection timing in diesel engine

A high-pressure fluid control solenoid valve assembly for use with a spill type fuel injection pump of an internal combustion engine, comprises an actuator portion (101) including a solenoid (8, 9), a stator (7) and an armature (14), and a valve portion (102) including a pilot valve (40, 41) and a main valve (42, 43) where the valve portion (102) is spaced apart from the actuator portion (101) and is responsive to the movement of the armature (14) via a rod (14) connected to the armature (14) and extends axially in a bore of the stator (7) which is cylindrical hollow. The pilot valve (40, 41) is coaxial with and telescopically received in the main valve (42, 43) so that two fluid chambers (54, 51) are formed inside and outside, respectively a spool (42) of the main valve such that the main valve is continuously kept closed irrespective of the fluid pressure in these chambers as long as the pilot valve is closed. The pilot valve comprises a needle (40) which is arranged to be pressed by the rod (13) to close the pilot valve on energization of the solenoid (8, 9), where the needle (40) is normally biased in valve-opening direction. On deenergization, the pilot valve opens causing the main valve to spill fuel thus terminating the fuel injection.

High-pressure fluid control solenoid valve assembly with coaxially

In determining an optimum target fuel ignition timing in accordance with the engine operating conditions, including at least an engine load and an engine speed, the target ignition timing is determined on the basis of a corrected engine load and a corrected engine speed. The corrected engine load and corrected engine speed are obtained by making corrections, according to the engine operating conditions, to a detected engine load and a detected engine speed, respectively. In this way, the optimum target fuel ignition timing according to the engine operating conditions can be obtained without directly detecting a fuel injection quantity.

Method and system for controlling fuel ignition timing in diesel engine

In controlling a fuel injection quantity by spilling a part of fuel fed from a high pressure chamber of a fuel injection pump using a high pressure electromagnetic valve which is on-off controlled by a driving circuit in accordance with engine operating conditions, switch means is provided between the high pressure electromagnetic valve and a power source, an output signal from the driving circuit is monitored, and the switch means is opened when the output signal from the driving circuit continues more than a predetermined period.

Fuel injection device in diesel engine

In controlling a time period of energization of a high pressure electromagnetic valve (50) in accordance with a target value of a fuel injection quantity determined from at least an engine speed (Ne) and an engine load, when a target indicated value (theta) of the time period of energization determined from at least the engine speed and the engine load is lower than a zero indicated value (theta.sub.0) of the time period of energization when the fuel injection quantity becomes zero, which is determined from the engine speed, the energization of the high pressure electromagnetic valve is cut off. Therefore, the duty cycle of the high pressure electromagnetic valve is decreased thereby increasing the reliability of the valve. In addition, fuel is reliably cut off when the fuel injection quantity is 0 mm.sup.3 /st thus avoiding fuel leakage and preventing the generation of white exhaust smoke. Fuel economy can therefore be improved.

Method and device for controlling energization of high pressure

In detecting a fuel injection timing in a diesel engine, a crank angle reference position is detected from rotation of a member rotatable in association with rotation of the engine, said member being disposed outside a fuel injection pump. While, in the fuel injection pump, a predetermined pump angle is detected from rotation of a member for converting rotary motion of a pump driving shaft into reciprocatory motion of a fuel pressure-feed plunger relative to the pump driving shaft, whereby the fuel injection timing is determined from a phase difference between the crank angle reference position and the predetermined pump angle. With this arrangement, the fuel injection pump can be assembled onto the engine without accurate measuring and an accuracy in detecting the fuel injection timing equal to or exceeding that in the conventional case can be obtained by more simplified adjustment than in the conventional case or with no adjustment.

Method and system for detecting fuel injection timing in a diesel engine

A fuel injection pump for a diesel engine includes a housing and a plunger which slides in a bore in the housing, with a high pressure chamber defined at an end of the plunger. The plunger rotates with the crankshaft and reciprocates so as to pump fuel from the high pressure chamber to the engine cylinders, under the control of an electromagnetic valve. This valve includes a pilot valve which selectively vents the high pressure chamber, which is operated to open and close by selective supply of electrical energy thereto, and a balance member which is driven by a fluid force arising when the pilot valve is thus opened and a relatively small flow of fuel is released from the high pressure chamber, and which when so driven releases a relatively large flow of fuel from the high pressure chamber. Thereby the response of the electromagnetic valve as a whole is made quick, so that it is possible to inject a pilot fuel injection spirt before the main spirt of fuel injection, thus slowing down the combustion speed when the engine is functioning under low load conditions, and thereby providing smooth and gradual combustion, thus preventing diesel knocking. Optionally, the pump may include a means for, after said electromagnetic valve has been actuated by supply of electric current in a particular direction, supplying electric current in the direction opposite to said particular direction thereto, so as to avoid problems caused by magnetization effects of the solenoid core.

Diesel fuel injection pump with electromagnetic fuel spilling valve

In a fuel injection system incorporating a distribution type fuel injection pump, wherein the amount of fuel in each fuel injection is controlled by the time duration from the stoppage to the resumption of the venting or spilling of the pumping chamber, the time duration is electronically calculated according to engine rotational speed and accelerator pedal opening amount as a rotational angle of the crankshaft. The value of the rotational angle is divided by a unit rotational angle of the crankshaft, as detected by a signal pickup from a signal rotor which rotates with an input shaft of the pump to obtain a quotient of an integer and a fractional remainder, and the rotational angle is measured by first counting the number of times that the crankshaft rotates through successive unit rotational angles equal to the integer of the quotient and, secondly, by adding a time equal to the product of the fractional remainder and a unit time which is equal to the time for the crankshaft to rotate through the unit rotational angle at the current engine rotational speed.

Diesel fuel injection pump with signal rotor giving reference position

A fuel injection pump for a diesel engine includes a housing having a bore within which a plunger reciprocates according to the operation of the engine, the bore defining a pumping chamber at an end of the plunger. The pumping chamber is communicated to a fuel intake passage only when the plunger is moving in a direction to enlarge the size of the pumping chamber and being communicated to fuel injection nozzles only when the plunger is moving in a direction to reduce the size of the pumping chamber. A first electromagnetic valve for fuel shutoff is provided at a middle portion of the fuel intake passage. A second electromagnetic valve, advantageously used also for fuel amount control by timely venting the pumping chamber in its compression stroke, communicates the pumping chamber to the intake passage downstream of the first electromagnetic valve for at least a predetermined short time period when the first electromagnetic valve is closed.

Diesel fuel injection pump with electronically controlled fuel spilling

A fuel injection pump for a diesel engine includes an input shaft rotated with the crankshaft, and a housing and a plunger which slides in a bore formed in the housing and is coaxial with the input shaft, with a high pressure chamber being defined at an end of the plunger between it and the bore. The plunger rotates with the input shaft and reciprocates so as to pump fuel at high pressure from the high pressure chamber to the engine cylinders, under the control of an electrically actuated electromagnetic valve, comprising a solenoid coil, which selectively vents the high pressure chamber according to the control of a control means, so as to provide fuel injection in appropriate amount to the diesel engine. There is provided a means for determining whether or not the voltage across the solenoid coil of the electromagnetic valve, when supply of power thereto changes from the ON to the OFF condition, rises higher than a certain value, or not. If a determining means detects that this voltage across the solenoid coil has not so risen, this lack of high transient voltage spike indicating that the solenoid coil may be discontinuous or functioning abnormally, then the engine is restrained. This restraint may consist of interrupting fuel flow to the engine to totally stop it, or of restricting air intake to the engine so as to put a ceiling on its rotational speed.

Diesel fuel injection pump with fuel injection cutoff upon detection of

A fuel injection pump for a diesel engine includes a means for calculating a proper fuel injection amount per each engine stroke and a means for injecting an amount of fuel per each engine stroke approximately equal to this proper fuel injection amount determined by this injection amount calculating means. The pump also includes a means for calculating a reference combustion time which represents approximately how long combustion in an engine stroke should last, and a means for detecting the approximate start and end of combustion in that engine stroke. From this information, these, an appropriate means calculates the approximate actual time of combustion in that engine stroke, and then another means compares the thus calculated approximate actual combustion time and the thus calculated reference combustion time, and based upon the result of said comparison selectively actuates a means for cutting off fuel injection, so as to stop the diesel engine from running and so as thereby to prevent overrunning due to abnormal combustion, if it decides as a result of the comparison that the actual combustion time is too long as compared with the reference combustion time. Optionally, this comparison may consider whether or not the calculated approximate actual combustion time has been greater than the calculated reference combustion time for a specified number of consecutive combustion cycles, and may interrupt engine running if such has been the case.

Diesel fuel injection pump fuel injection cutoff upon detection of

In order to prevent warm or cool blast from an air conditioner from blowing through the interspace between the bottom of a seat cushion and the floor of the body of a car, a warm or cool blast-intercepting member is disposed at a front end and side ends under the seat cushion.

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Toyota, Japan

Fumiaki Kobayashi