Abstract: A laser ignition device includes a laser oscillation optical system that produces pulsed laser light, a condensing optical element that condenses the pulsed laser light into a combustion chamber, a housing that internally contains the condensing optical element, and an optical window that is provided distally with respect to the condensing optical element in the housing and transmits the pulsed laser light. The pulsed laser light is shaped as a ring around an optical axis at least at a light passage position in the optical window.

Abstract: A laser ignition device capable of achieving stable ignition, preventing deterioration of a semiconductor laser element is provided, by suppressing the intensity of oscillated light leakage leaking towards semiconductor laser side from the laser resonator with a simple configuration. A laser ignition device 7 includes an excitation light source 1 emitting coherent excitation light LPMP, an optical element 2 transmitting excitation light LPMP, a laser resonator 3 oscillating oscillated light having high energy density by being irradiated with excitation light LPMP, and condensing means 6 condensing the oscillated light LPLS oscillated by the laser resonator 3. Moreover, the laser ignition device 7 is provided with a light-transmissive-reflective film 5 disposed between the excitation light source 1 and the laser resonator 3. The light-transmissive-reflective film 5 permeating the excitation light LPMP having short wavelength and reflecting oscillated light leakage LLEAK having long wavelength.

Abstract: In an ignition device having an ignition plug for igniting a fuel mixture gas introduced in a combustion chamber, a super hydrophilic membrane is formed on a surface at the combustion chamber side of a plug forming member of the ignition plug. The super hydrophilic membrane contains super hydrophilic particles and thermal excitation catalyst particles, and satisfies a relationship of ?W2<?W1, where ?W1 indicates a water contact angle between water and the plug forming member on which no super hydrophilic membrane is formed, and ?W2 indicates a water contact angle between water and the plug forming member on which the super hydrophilic membrane is formed.

Abstract: In a laser ignition device which is mounted in an internal combustion engine and at least includes a laser spark plug equipped with an optical window which protects an optical device from high temperature and high pressure generated in a combustion chamber and a prechamber cap equipped with a cylindrical prechamber, a prechamber throat portion that is a bottomed cylinder with a sectional area smaller than that of the prechamber, and a plurality of prechamber spray holes which communicate with a combustion chamber on a side of a closed end of the prechamber throat portion, the prechamber cap is arranged between the optical window and the combustion chamber. A converging point FP is located inside the prechamber to ignite an air-fuel mixture delivered into the prechamber, thereby jetting combustion flames from the prechamber into the combustion chamber to fire the internal combustion engine.

Abstract: In an ignition device having an ignition plug for igniting a fuel mixture gas introduced in a combustion chamber, a super hydrophilic membrane is formed on a surface at the combustion chamber side of a plug forming member of the ignition plug. The super hydrophilic membrane contains super hydrophilic particles and thermal excitation catalyst particles, and satisfies a relationship of ?W2<?W1, where ?W1 indicates a water contact angle between water and the plug forming member on which no super hydrophilic membrane is formed, and ?W2 indicates a water contact angle between water and the plug forming member on which the super hydrophilic membrane is formed.

Abstract: In a laser ignition device which is mounted in an internal combustion engine and at least includes a laser spark plug equipped with an optical window which protects an optical device from high temperature and high pressure generated in a combustion chamber and a prechamber cap equipped with a cylindrical prechamber, a prechamber throat portion that is a bottomed cylinder with a sectional area smaller than that of the prechamber, and a plurality of prechamber spray holes which communicate with a combustion chamber on a side of a closed end of the prechamber throat portion, the prechamber cap is arranged between the optical window and the combustion chamber. A converging point FP is located inside the prechamber to ignite an air-fuel mixture delivered into the prechamber, thereby jetting combustion flames from the prechamber into the combustion chamber to fire the internal combustion engine.

Abstract: A laser ignition device capable of achieving stable ignition, preventing deterioration of a semiconductor laser element is provided, by suppressing the intensity of oscillated light leakage leaking towards semiconductor laser side from the laser resonator with a simple configuration. A laser ignition device 7 includes an excitation light source 1 emitting coherent excitation light LPMP, an optical element 2 transmitting excitation light LPMP, a laser resonator 3 oscillating oscillated light having high energy density by being irradiated with excitation light LPMP, and condensing means 6 condensing the oscillated light LPLS oscillated by the laser resonator 3. Moreover, the laser ignition device 7 is provided with a light-transmissive-reflective film 5 disposed between the excitation light source 1 and the laser resonator 3. The light-transmissive-reflective is film 5 permeating the excitation light LPMP having short wavelength and reflecting oscillated light leakage LLEAK having long wavelength.

Abstract: In a laser ignition apparatus, a focusing optical element is configured to focus a pulsed laser light to a predetermined focal point in a combustion chamber of an engine. An optical window member is arranged on the combustion chamber side of the focusing optical element so as to separate the focusing optical element from the combustion chamber. A catoptric-light focal point, at which a catoptric light is to be focused, is positioned on the anti-combustion chamber side of a combustion chamber-side end surface of the optical window member. The catoptric light results from the reflection of the pulsed laser light by a pseudo mirror that is formed by the optical window member when the combustion chamber-side end surface thereof is fouled with contaminants. Further, the catoptric-light focal point falls in a region where no solid material forming either the focusing optical element or the optical window member exists.

Abstract: A laser ignition apparatus includes a housing that has a male-threaded portion for fixing the housing and a hexagonal portion for tightening the male-threaded portion. Between a combustion chamber-side end of the male-threaded portion and an anti-combustion chamber-side end of the hexagonal portion, there is defined a non-optical element arrangement region in which none of an introducing optical element, an enlarging optical element and a focusing optical element of the apparatus is arranged. At one of a combustion chamber-side end and an anti-combustion chamber-side end of the non-optical element arrangement region, there is formed a reference surface that extends perpendicular to an axial direction of the housing. One of the introducing optical element, the enlarging optical element and the focusing optical element is received in the housing in such a manner as to be elastically pressed against the reference surface from outside of the non-optical element arrangement region.

Abstract: A laser ignition system that is mounted on an internal combustion engine and that condenses a laser beam oscillated from a laser oscillator into an engine combustion chamber by using a condenser lens to generate a flame kernel with high energy and to perform ignition includes at least a highly-refractive optical element that refracts optical axes OPX1 to OPXn of plural laser beams oscillated from plural semiconductor lasers 5-1 to 5-n through a resonator to change traveling directions of the laser beams and a condenser device that condenses the laser beams refracted by the highly-refractive optical element on plural positions FP1 to FPn in the engine combustion chamber.

Abstract: There is provided a semiconductor laser pumped solid-state laser device for engine ignition that can stably provide optical energy required for ignition across a wide temperature range. In the semiconductor laser pumped solid-state laser device for engine ignition, a plurality of semiconductor lasers 21, 22, 23, and 24 are used that have locking ranges, a temperature width thereof divided into a plurality of temperature ranges corresponding to a variation width of an ambient temperature, and that have the respective wavelengths falling within an absorption wavelength band of a solid-state laser medium 5 of the solid-state laser device in the temperature width of each locking range, to pump the solid-state laser medium 5 by multiplexing emitted lights from the plurality of semiconductor lasers 21, 22, 23, and 24 using a multiplexing mechanism to irradiate the solid-state laser medium 5.

Abstract: A laser type ignition device for an internal combustion engine includes a laser oscillator mounted in the internal combustion engine so as to focus its laser beam on an air-fuel mixture supplied into the combustion chamber, a pressure sensor for detecting pressure in the combustion chamber, a power source for the laser oscillator and a control unit for controlling the power source to supply the laser oscillator with the current whose amount changes according to the pressure in the combustion chamber. The power of the laser beam increases as the pressure in the combustion chamber decreases to completely ignite the air-fuel mixture.

Abstract: A laser type ignition device for an internal combustion engine includes a laser oscillator mounted in the internal combustion engine so as to focus its laser beam on an air-fuel mixture supplied into the combustion chamber, a pressure sensor for detecting pressure in the combustion chamber, a power source for the laser oscillator and a control unit for controlling the power source to supply the laser oscillator with the current whose amount changes according to the pressure in the combustion chamber. The power of the laser beam increases as the pressure in the combustion chamber decreases to completely ignite the air-fuel mixture.

Abstract: An injector has an orifice plate formed with plural orifices. At a radially outward position of the orifice plate is disposed a wall at least partially. It is preferable that the wall be disposed at a lower position in the direction of gravity. In the wall is formed a guide hole toward an area on the orifice plate where a strong negative pressure is developed. A portion of fuel injected from the injector adheres as adhered fuel to the orifice plate or the wall. Under the action of a negative pressure on the orifice plate the guide hole sucks in the adhered fuel and returns it onto the surface of the orifice plate. The adhered fuel flows from the wall onto the surface of the orifice plate and again joins a fuel jet injected from the orifices. By utilizing a negative pressure developed near the plural orifices, the adhered fuel can be recovered and again injected. Consequently, it is possible to decrease the amount of adhered fuel.

Abstract: It is an object to provide a continuously variable valve timing adjusting device to improve valve timing advance response for an internal combustion engine. The device, capable of continuously and variably controlling the intake valve timing phase, includes: an advance chamber which hydraulically rotates a vane rotor and a camshaft on the advance side relative to the timing rotor; a retard chamber for rotating the camshaft on the retard side relative to the timing rotor; an advance-retard oil pressure control valve; an oil communicating passage for fluid communication between the advance chamber and the retard chamber; a hydraulic piston, flow control valve which controls the oil in the communicating passage according to the retard chamber pressure when the engine is running at a low speed and a high oil temperature; and a ball valve check valve which checks the oil flow from the advance chamber to the retard chamber.

Abstract: An injector has an orifice plate formed with plural orifices. At a radially outward position of the orifice plate is disposed a wall at least partially. It is preferable that the wall be disposed at a lower position in the direction of gravity. In the wall is formed a guide hole toward an area on the orifice plate where a strong negative pressure is developed. A portion of fuel injected from the injector adheres as adhered fuel to the orifice plate or the wall. Under the action of a negative pressure on the orifice plate the guide hole sucks in the adhered fuel and returns it onto the surface of the orifice plate. The adhered fuel flows from the wall onto the surface of the orifice plate and again joins a fuel jet injected from the orifices. By utilizing a negative pressure developed near the plural orifices, the adhered fuel can be recovered and again injected. Consequently, it is possible to decrease the amount of adhered fuel.

Abstract: A holographic particle-measuring apparatus is provided that can improve the precision of measurement by photographing only particles through the elimination of noise. In an off-axis holographic optical image pick-up device (100), object beams (L1) that is a flux of parallel beams are irradiated onto particles (114) as a subject. At the same time, reference beams (L2) are incident, with an inclination, onto the object beams (L1) after being irradiated onto the particles (114). An interference fringe generated as a result of the interference between the object beams (L1) and the reference beams (L2) is recorded onto a recording material Noise elimination relay lenses (116a and 116b) are installed between the particles (114) and the recording material (115). Further, a noise elimination pinhole plate (117) having a pinhole (118) is installed between the lenses (116a and 116b) constituting the relay lens.

Abstract: A damping chamber is formed in a pressure relaxation device connected to a high pressure fuel pipe. Valve bodies are provided at openings of partitions, and a spring force is applied to the valve bodies by a spring in a valve closing direction. When a high pressure portion reaches an inlet of the damping chamber, the valve body opens to hold and absorb the high pressure portion in the damping chamber. When a low pressure portion reaches the inlet of the damping chamber, the high pressure portion held in the damping chamber is gradually released via a restricted orifice to cancel the low pressure portion, thereby reducing the pressure pulsation of fuel.

Abstract: It is an object to provide a continuously variable valve timing adjusting device to improve valve timing advance response for an internal combustion engine. The device, capable of continuously and variably controlling the intake valve timing phase, includes: an advance chamber which hydraulically rotates a vane rotor and a camshaft on the advance side relative to the timing rotor; a retard chamber for rotating the camshaft on the retard side relative to the timing rotor; an advance-retard oil pressure control valve; an oil communicating passage for fluid communication between the advance chamber and the retard chamber; a hydraulic piston, flow control valve which controls the oil in the communicating passage according to the retard chamber pressure when the engine is running at a low speed and a high oil temperature; and a ball valve check valve which checks the oil flow from the advance chamber to the retard chamber.

Abstract: An air-fuel ratio control system for a gas-fueled engine which is capable of achieving the combustion in a target air-fuel ratio to surely purify an exhaust gas through an exhaust purification catalyst. In the air-fuel ratio control system, a three-way catalytic converter is placed in an exhaust pipe of the engine and an O2 sensor is located on the upstream side of the three-way catalytic converter. The O2 sensor comprises an element, and an atmosphere side electrode is formed on an inner surface of the element while an exhaust gas side electrode is formed on an outer surface thereof. The exhaust gas side electrode is coated with a catalyst layer which can remove hydrogen through a catalytic reaction. A control unit of the control system controls a fuel supply quantity by a gas injector using a feedback correction coefficient on the basis of the output of the O2 sensor, thereby reducing the deviation between an air-fuel ratio measured by the O2 sensor and a target air-fuel ratio.