Ngk Spark Plug Company, Limited

Toyota Jidosha Kabushiki Kaisha

Denso Corporation

Other

Nippondenso Co., Ltd.

Toyota Jidosha Kogyo Kabushiki Kaisha

Takata Corporation

Yasuo Ito

Shigeru Miyata

Hideji Yoshida

Yoshihiro Matsubara

Kazuhisa Mogi

Koichi Nakata

Yoshitaka Yamada

Takashi Suzuki

Keiichiro Aoki

Nobuhiro Hayakawa

Takahiro Kojo

Takeshi Matsui

Noboru Yamamoto

Takayasu Zushi

Yuichi Nanbu

Masami Sawada

Tessho Yamada

Kazuhiro Yamada

Masahiro Miyata

Hisashi Kameya

Katsuki Aoi

Shinji Ooyabu

Kenichiro Hidaka

Akio Ito

Tomohiro Hirata

Sadamitsu Harada

Masakuni Tsujimura

Youichi Kurebayashi

Koji Yonekura

Kiyotaka Sasaki

Kouichi Kato

Junichi Kawamoto

Eiji Takakuwa

Toshiaki Yamaura

Yoshitaka Fujikawa

Tamotsu Nakamua

Motoyuki Nakamura

Yoshiaki Yamaoto

Hideji Tani

Kenji Hashimoto

Mitsutomo Iwase

An inverter circuit includes a bridge circuit constituted of a plurality of pairs of a high-side switching element and a low-side switching element, a command signal processing section, a pulse generating section for generating pulse signals to control the inverter bridge circuit according to the command signal to have a dead time to prevent short circuiting of the dc power source and a command signal compensation section. The compensation section modifies the command signal according to a current voltage level of the dc power source to control the dead zone, thereby preventing deformation of ac output power of the bridge circuit.

Inverter circuit free from power-source-voltage fluctuation

A knock sensor comprises a sensor body having a metallic shell including a cylindrical portion and a flange portion formed at an end of the cylindrical portion, an annular piezoelectric element fitted around the cylindrical portion and an annular weighting member fitted around the cylindrical portion to hold the piezoelectric element between the weighting member and the flange portion, and a resin-molded sensor casing arranged circumferentially around the sensor body. The resin-molded sensor casing includes a weighting portion located nearer to the weighting member than to the piezoelectric element with respect to an axial direction of the cylindrical portion, and at least the weighting portion of the resin-molded sensor casing is made of a resin containing at least one of metal powder and metal oxide powder and has a density of 2.0 g/cm or higher.

Nonresonant type knock sensor

In a direct fuel injection engine, an ignition coil generates a high voltage applied to a spark plug at a desired ignition time and a similar ignition voltage is then continued to be repeatedly generated at a fixed frequency so that the spark plug generates multiple sparks in each ignition cycle. The number of sparks included in the multiple is reduced as an engine speed rises. The multiple spark generating operation is disabled when the engine is in a high speed and/or high load region of operation.

Ignition control for fuel direct injection type engine

A knock detection device for an internal combustion engine make provisions to prevent erroneous decisions from being made due to a steplike signal change at the time of mask removal or to an overlap between an LC resonance generation period and a knock occurrence period in high engine rpm conditions. A low-frequency component is removed from an ion current signal by an HPF, and the resulting flat signal is supplied to a mask circuit, thereby reducing the amount of discontinuity occurring at the time of mask removal and suppressing noise in an output signal of a BPF to a level that does not affect knock detection. Further, by setting the gate period in a peak-hold circuit slightly delayed with respect to the mask removal timing, noise associated with the mask removal is completely eliminated. As mask signals used to specify the mask period, in addition to a mask signal for removing the mask when a predetermined crankshaft angle is reached, a second signal is provided for removing the mask when a prescribed time required for LC resonance noise to settle down has elapsed from the end of spark discharge, and the mask is removed only when both of the mask signals are deactivated.

Knock detection device for an internal combustion engine avoiding

Disclosed is a knock control device for an internal combustion engine wherein, when performing knock control based on an ion current detected using a configuration containing an ignition coil secondary in an ion current path, a knock detection gate period is controlled appropriately in accordance with variation of a mask period in order to ensure complete removal of residual magnetic noise. An ion current output detected through an ion current detection circuit and an inverting amplifier circuit is masked by a mask circuit until a prescribed time elapses after the end of spark discharge, thereby accomplishing complete removal of noise occurring after the end of the discharge. A band-pass filter (BPF) extracts a knock frequency component from the output of the mask circuit, and an integrator circuit integrates the output of the BPF during the gate period. A CPU learns the initiation timing of the gate period in accordance with variation of the end timing of the mask period so that the initiation timing of the gate period occurs later than the end timing of the mask period. As a result, the effects of the noise caused by a signal discontinuity associated with mask removal are eliminated.

Knock control device for internal combustion engine

A combustion state detector apparatus for an internal combustion engine has a current detection device for detecting a current flowing between the ignition plug and a ground, and an ignition driving device for driving the ignition plug on the basis of an ignition instruction signal from an electronic control device of the internal combustion engine. An independent unit including a current detection device and an ignition driving device, is provided for each cylinder of the internal combustion engine. With respect to each cylinder, the apparatus determines whether a misfire has occurred on the basis of the current flowing between the ignition plug and the ground at the time of combustion. The apparatus is also capable of detecting abnormalities and/or wire breakages in a signal system provided for signal transmission between each independent unit and the electronic control device of the internal combustion engine.

Combustion state detector apparatus for an internal combustion engine

A knock detection device for an internal combustion engine prevents erroneous knock detection decisions from being made due to an LC resonant current in an ion current path. An LC resonance frequency, which is determined based on an inductance of ignition coil secondary and a stray capacitance formed in the ion current path, is set so as to be displaced from a knock frequency so that the knock frequency component alone can be detected accurately from the ion current output. Preferably, the inductance of the ignition coil secondary is set to a large value, thereby setting the LC resonance frequency lower than the knock frequency and thus improving ignitability as well as knock detectability. Also preferably, the LC resonance frequency is set to a value lower than a lower cut-off frequency of a knock signal extraction band-pass filter provided in a processing circuit. This ensures more reliable elimination of the noise causing LC resonance frequency component.

Knock detecting device for internal combustion engine

A knocking detecting sensor (1) includes a piezoelectric element plate (8) for detecting vibration due to knocking generated in an internal combustion engine and a main metallic sleeve (5) for supporting the piezoelectric element plate (8) on the side of one face. The sensor (1) is attached to a prescribed attaching unit (30) of an internal combustion engine. The piezoelectric element plate (8) is formed in a flat axis-symmetrical shape at a position relative to an axial line (O) that is substantially orthogonal to the attaching face (30a) of the attaching unit (30). The main metallic shell (5) has an opposite face (35) to the attaching face (30a) of the attaching unit (30), and has a notch portion (37) opening toward the opposite face (35) at a position a prescribed distance away from the axial line (O). By providing the notch portion (37), the center of gravity (G) of the sensor (1) can be corrected so that it approaches the axial line (O).

Knocking detecting sensor

An apparatus for detecting a condition of burning in an internal combustion engine includes a spark plug and an ignition coil. The ignition coil has a primary winding and a secondary winding. The secondary winding is connected to the spark plug. An ion current sensing resistor is connected to a low voltage side of the secondary winding of the ignition coil for sensing an ion current. A diode is connected in parallel with the primary winding of the ignition coil. A switching element is connected in series with the primary winding of the ignition coil. The switching element is movable into and out of an on state. A suitable device is operative for resisting a current flowing through the diode when the switching element is in the on state.

Apparatus for detecting condition of burning in internal combustion

A device for controlling knocking includes a first unit which applies a voltage across a pair of electrodes installed in a combustion chamber of the internal combustion engine, detects an ionic current flowing between said pair of electrodes through ions generated when a gas mixture in the combustion chamber burns, and discriminates whether the knocking is occurring or not based upon the ionic current that is detected. The device for controlling knocking further includes a second unit which detects vibration of the cylinder block by using a vibration sensor installed in the cylinder block of the internal combustion engine, and discriminates whether the knocking is occurring or not based upon the vibration of the cylinder block that is detected. The device for controlling knocking controls the ignition timing of the internal combustion engine based upon the result of discrimination of either the first unit or the second unit depending upon the operation region of the internal combustion engine. The device for controlling knocking maintains a high knocking detecting precision and a high ignition timing control precision throughout the whole operation region of the internal combustion engine and for all cylinders.

Device for controlling knocking in an internal combustion engine

In a spark plug voltage probe device which detects a voltage applied to a spark plug installed in an internal combustion engine so as to analyze a burning condition in the internal combustion engine on the basis of the voltage applied to the spark plug, a rubber clamper (9) is secured to the internal combustion engine, and having a groove (92) in which a spark cable (60) is located so as to form a static capacity between the rubber clamper (9) and the spark plug cable (60). An electrical conductor (93) is embedded in the rubber clamper (9) along the groove (92) while the electrical conductor (93) is connected to a microcomputer by way of an output cable (64) so as to analyze a spark plug voltage waveform. A condenser (42) is connected to a common point (A) between the electrical conductor (93) and the microcomputer so as to reduce the spark plug voltage according to a capacity of the condenser (42).

Spark plug voltage probe device in an internal combustion engine

In a sparkplug voltage probe device in use for an internal combustion engine, an insulator base is attached to the internal combustion engine, an upper surface of the insulator base having a plurality of grooves in which the sparkplug cables are placed. An insulator sheet is embedded in the insulator base. An electrode layer is provided on an upper surface of the insulator base along the grooves to form a static capacity between the electrode layer and the sparkplug cables when the voltage is applied across the spark plugs. On a lower surface of the insulator sheet an electrical shield layer is provided connected to the internal combustion engine by a ground wire. A lead wire electrically connects the electrode plate to a microcomputer so as to analyze the engine burning condition based on the static capacity between the electrode plate and the sparkplug cables.

Sparkplug voltage probe for use with an internal combustion engine by

In a sparkplug voltage probe device, an insulator base is attached to the internal combustion engine, an upper surface of the insulator base having a plurality of grooves in which the corresponding cables are placed. An electrode plate is embedded in the insulator base along the grooves to form a static capacity between the electrode plate and an array of all the cables in the grooves, both of the longitudinal sides of the electrode plate being curled around the outermost cables respectively to compensate shortage of static capacitance so as to form a capacitance adjusting function in order to substantially even a distribution of the static capacity between the electrode plate and the array of all the cables in a direction perpendicular to a length of the electrode plate. A lead wire is provided to electrically connect the electrode plate to a microcomputer.

Sparkplug voltage probe device having a capacitance compensating

In a spark plug voltage probe device which detects voltage applied to a spark plug installed in an internal combustion engine so as to analyze burning conditions in the internal combustion engine on the basis of the voltage applied to the spark plug, a rubber collar (74) is provided to surround rubber cap (7) secured to high tension terminal (71a) of spark plug (71) so as to form a static capacity between high tension terminal (71a) and rubber collar (74). Electrical conductor (73) is provided between rubber cap (7) and rubber collar (74), and conductor (73) is electrically connected to a microcomputer by output cable (64) so as to analyze the spark plug voltage waveform. Condenser (42) is connected at one end to the ground and the other end to a common point (A) between electrical conductor (73) and the microcomputer so as to reduce the spark plug voltage according to the capacity of condenser (42).

Spark plug voltage probe device for use in an internal combustion engine

In a snap-in type spark plug voltage probe device, the insulator base has an upper half and a lower half, both ends of which are integrally connected by means of a flexible portion. The upper half and the lower half have a plurality of grooves in which spark plug cables are placed. The upper half and the lower half are joined together by the flexible portion when in a closed position. The upper half has an opening to receive a protrusion provided on the lower half of the insulator base to maintain the upper half of the insulator base along the grooves, providing static capacity between the electrode layer and the spark plug cables when voltage is applied across the spark plugs. A lead wire electrically connects the electrode layer to a microcomputer so as to analyze the burning condition based on the static capacity between the electrode layer and the spark plug cables. An electrical shield layer is embedded in the insulator base in the proximity of the electrode layer and connected to the internal combustion engine by way of a ground wire located at a side of the electrode layer remote from the grooves so as to electrically shield the electrical layer. An insulator sheet is embedded in the insulator base and located between the electrode layer and the electrical shield layer.

Snap-in type sparkplug voltage probe device for use in internal

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Nagoya, Japan

Yasuo Ito