Kabushiki Kaisha Toyota Chuo Kenkyusho

Kiyokazu Asai

Akihiro Takeuchi

Yujiro Oshima

Hiroharu Tokoro

Yasuaki Kawai

Shigetsune Aoyama

An ultrasonic motor which has a viration mode of progressive wave with a large vibrational amplitude of an elastic member and which provides a high torque, comprises: at least one vibrator including a disk-shaped elastic member having a driving force transmitting portion, disk-shaped piezoelectric ceramics attached to both surfaces of the elastic member and a plurality of projections provided on both sides of the driving force transmitting portion; and at least one rotor that is in press contact with the driving force transmitting portion of the vibrator. The thickness of the elastic member at a portion between the piezoelectric ceramics is substantially equal to the thickness thereof at the driving force transmitting portion.

Ultrasonic motor

A method and device for detection of knocking in an internal combustion engine which can not only detect knocking but also an abnormal condition of a cooling liquid in a liquid cooled engine. The device detects the vibration or pressure fluctuations of the cooling liquid generated by both knocking and the operating of the coolant pump.

Method of and device for detection of knocking for internal combustion

A knocking detecting device for an internal combustion engine including: a casing in the form of an annular member fastened substantially perpendicularly to an outer sidewall of the engine block; a support member made of a vibration-isolating material such as rubber or synthetic resin, and having one end fastened to the casing and the other end projecting a predetermined distance from the outer sidewall of the engine block to a position within a water chamber or a coolant water passage; a pressure-sensitive member including pressure-sensitive surfaces mounted on the projecting end of the support member, facing away from each other and extending perpendicularly to the outer sidewall of the engine block, for detecting as a change in an electrical signal pressure vibrations transmitted as a knocking sound to the pressure-sensitive surfaces through coolant water from the partition when knocking is produced in the combustion chamber; and lead wires for delivering the electrical signal change responsive to the knocking. This device enables effective detection of only the knocking produced in the combustion chamber as the pressure vibrations in the coolant water.

Knocking detecting device for internal combustion engines

An electrical circuit for driving a piezoelectric transducer includes a DC electric source, a constant current circuit, connected to the DC electric source for processing a DC signal from the DC electric source and supplying a constant output current having a predetermined constant value, and an oscillation circuit connected to the constant current circuit for driving the piezoelectric transducer with a resonance frequency and with a constant current. The electrical circuit approximately drives the piezoelectric transducer with a constant current by supplying the constant current to the oscillation circuit.

Constant current electrical circuit for driving piezoelectric transducer

A device for inspecting spot welds which comprises a probe for receiving a reflected wave from an inspection material, a weld state display unit for displaying a waveform, a pulse interval and a number of pulses of the reflected wave, and a wave guide connected to an end portion of the probe, for guiding the reflected wave from the inspection material to the probe. The wave guide has an ultrasonic wave propagating section in the form of a cylinder and an internal ultrasonic wave absorbing section obtained by filling an inside hole of the cylinder with an ultrasonic wave absorbing material, the ultrasonic wave propagating section being so dimensioned that the length of an ultrasonic wave propagating path is within the range calculated from the following equation:

Device for inspecting spot welds

An ultrasonic transducer comprising a first cylindrical member which includes a mechanical vibration amplifying part formed in symmetry around the axis thereof and having a gradually increased cross-sectional area toward a base portion thereof, the base portion having a flat surface perpendicular to the axis thereof, and an annular rigid part formed with the mechanical vibration amplifying part coaxially therewith, the annular rigid part being extended from the outer wall of the base portion axially and radially outwardly to have sufficient rigidity and weight, and the annular rigid part being provided, in the proximity of the outer wall of the base portion, with an annular groove or gap having a predetermined axial depth in order to reduce the diameter of the flat surface. The transducer further comprises a second cylindrical member which includes a backing block of a cylindrical body, a base portion of which is formed with a flange and a flat surface perpendicular to the axis thereof having the larger diameter than that of the flat surface of the first cylindrical member. An ultrasonic transducer portion is interposed between the flat surfaces of the first and second cylindrical members and comprises a pair of piezoelectric elements having flat surfaces perpendicular to the axis of the first and second surfaces, and an electrode plate interposed between the pair of piezoelectric elements. A fastening device pressingly abuts the flat surfaces of the piezoelectric elements against the flat surfaces of first and second cylindrical members and integrally clamps the annular rigid part and the flange of the second cylindrical member to each other in a manner to circumvent said annular groove or gap. The ultrasonic transducer prevents the flexural vibration of the flat surface of the first cylindrical member and prevents cracking of piezoelectric elements to ensure stabilized operations without transitional variations in electric impedance and resonance frequency and to allow continuous vibrating operations in large amplitude over a long period of time.

Piezoelectrically driven ultrasonic transducer

An ultrasonic wave carburetor includes an intake passage for admitting fresh air and supplying an air-fuel mixture therethrough, and a fuel supply device including a fuel reservoir, a venturi, and a nozzle one end of which is open into the venturi and the other end of which is communicated with the fuel reservoir. A fuel atomizing device, including an ultrasonic transducer connected to an ultrasonic wave oscillator for transforming an electrical oscillation into a mechanical vibration, a mechanical vibration amplifying member secured to the ultrasonic transducer for amplifying the mechanical vibration, and an ultrasonic vibratory member, having a hollow cylindrical body structure, secured to the amplifying portion, is positioned downstream of the venturi. With this structure, fuel supplied through the nozzle in the fuel supplying device is atomized on the peripheral surfaces of the ultrasonic vibratory member.

Ultrasonic wave carburetor

An ultrasonic wave fuel injection and supply device includes an ultrasonic wave generating device and a fuel injection nozzle device. The ultrasonic wave generating device in turn includes an ultrasonic transformer, for transforming electrical oscillations into mechanical vibrations, connected to an ultrasonic oscillator, a mechanical vibration amplifier, for amplifying the amplitude of the mechanical vibrations, secured to the ultrasonic transformer, and a vibratory member, having a hollow cylindrically shaped body the peripheral wall of which is secured to the tip of the mechanical vibration amplifier with the axis of the vibratory member being disposed substantially perpendicular to the longitudinal axis of the mechanical vibration amplifier. The vibratory member has its opposite ends open and is disposed within an intake passage of an engine, the same therefore not hindering the flow of fluid through the intake passage. The fuel injection nozzle has its nozzle opening directed toward the peripheral wall of the vibratory member for injecting liquid fuel under pressure onto the peripheral wall. A fuel supply device introduces liquid fuel from a fuel reservoir to the injection nozzle, and a control device controls the amount of fuel being injected through the injection nozzle in response to the running conditions of the internal combustion engine. The ultrasonic wave fuel injection and supply device thus atomizes and scatters the liquid fuel injected onto the peripheral wall of the vibratory member as a result of the ultrasonic vibrations thereof, and the atomized and scattered liquid fuel is supplied to the combustion chamber of an engine, together with air from an air cleaner.

Ultrasonic wave fuel injection and supply device

An ultrasonic wave generator includes an ultrasonic oscillator, an ultrasonic wave transducer connected to the oscillator, a mechanical vibration amplifying member, and an ultrasonic vibratory member. An increased thickness portion, which projects from a portion of the circumferential surface of the ultrasonic vibratory member and from a side wall portion of the mechanical vibration amplifying member at a connecting portion of the ultrasonic vibratory member and the mechanical vibration amplifying member, is integrally formed upon the ultrasonic vibratory member and the mechanical vibration amplifying member whereby the cross-sectional area of the connecting portion between the ultrasonic vibratory member and mechanical vibration amplifying member is gradually changed. With this improvement, the mechanical strength of the connecting portion between the ultrasonic vibratory member and the mechanical vibration amplifying member is increased, the positive transmission of the ultrasonic waves from the mechanical vibration amplifying member to the ultrasonic vibratory member is insured, fatigue failure and cracking of the connecting portion is effectively prevented, and the ultrasonic waves are generated from the ultrasonic vibratory member in a stable manner for a long period of time.

Ultrasonic wave generator

The ultrasonic wave generator incorporates an ultrasonic-frequency vibratory member of cylindrical shape from which ultrasonic waves are produced, and the vibratory member is securely connected of its outer cylindrical surface to the mechanical vibration output end of a metallic block amplifier member which in turn is connected to an ultrasonic electromechanical transducer of the piezoelectric type, etc. The cylindrically shaped vibratory member effects a motion of flexural vibrations in the radial direction throughout its extensive areas, producing large-amplitude ultrasonic waves.

Resonant cylindrically shaped ultrasonic wave generator

A liquid atomizing apparatus includes an ultrasonic wave transducer connected to an ultrasonic wave oscillator for transforming an electrical oscillation into a mechanical vibration, and a mechanical vibration amplifying member has one end thereof integrally secured to one end of the ultrasonic wave transducer for amplifying the amplitude of the mechanical vibrations transmitted from the ultrasonic wave transducer. An ultrasonic vibratory member of a hollow cylindrical body, which has a predetermined wall thickness, has a portion of its outer circumferential surface integrally secured to the other end of the mechanical vibration amplifying member and a liquid supply means connected to a liquid source for supplying a liquid of a given amount to the circumferential surface of the ultrasonic vibratory member is also provided, the liquid being supplied to the circumferential surface of the ultrasonic vibratory member being atomized upon such circumferential surface of the ultrasonic vibratory member. The liquid atomizing apparatus is capable of atomizing a large amount of liquid upon the outer and/or inner circumferential surfaces of the vibratory member, and achieves a consistent and stable atomization of the liquid while maintaining the size of the atomized liquid particles, and the distribution of the particles, uniform.

Growing community of inventors

Nagoya, Japan

Kiyokazu Asai