摘要:
A valve system of an overhead-camshaft-type internal combustion engine includes a cam holder fastened to a cylinder head having a combustion chamber formed therein. The cam holder supports a camshaft, and is disposed above the combustion chamber. The cam holder includes a bottom wall, a pair of oppositely-facing support walls having lower sides thereof joined with each other by the bottom wall, and a rib joining predetermined oppositely-facing portions of respective upper side portions of the support walls with each other. The support walls of the cam holder pivotally support the cam shaft. The rib may be integrated with the cam holder, or may be separately formed and fastened to the support walls of the cam holder.
摘要:
This invention provides an ultrasonic imaging system that implements imaging by distinguishing sharply and definitely the echo components generated by scattering in a microbubble contrast medium, from the tissue harmonic components generated by nonlinear propagation of a transmitted pulse. This ultrasonic imaging system, constructed to transmit/receive ultrasonic pulses to/from a living body and form a contrast image of the inside of the living body by using the contrast-imaging microbubbles, repeats the transmitting/receiving operations four times in all, under the same transmitting/receiving focus conditions at different phase angles [(a)=0°, (b)=120°, (c)=−120°, (d)=180°] of the carrier of a transmitted pulse wave including a common envelope signal, sums up three time-series receive echo signals associated with (a), (b), (c), forms the contrast image, sums up two time-series receive echo signals associated with (a), (d), forms an image of the living body having a nonlinear pulse propagation property, and makes a superimposed display of the two kinds of images.
摘要:
An ultrasonograph capable of generating a transmission beam comprising a main beam having a uniform width over a wide range in an ultrasonic wave propagation direction by one-time transmission of an ultrasonic pulse. A weighted mean value of a plurality of transmission delay time values corresponding to focal lengths of transmission pulse waves having a plurality of focal points which are set in the ultrasonic wave propagation direction is calculated for each of elements constituting a transmission aperture and used as the delay time. The curvature of a transmitted wave front is close to a short focal length in the center portion of the transmit aperture and is close to a long focal length in the peripheral portion. Thus, a transmission beam including a relatively narrow main beam with a uniform width over a wide range in the ultrasonic wave propagation direction can be generated.
摘要:
An air fuel injection engine including an injector composed of a fuel injection valve for injecting fuel and an air fuel injection valve for directly injecting fuel together with compressed air into a combustion chamber and an injector housing for holding and securing the injector to an engine body. The injector is supported on a head cover, and at least part of a compressed air supply passage for supplying compressed air to the injector is provided directly in the head cover. Further, an injector housing is formed integrally with a head cover which forms part of an engine body. With this configuration, the scale of the engine, the complication of the structure around the engine, and the number of part required can be kept to a minimum.
摘要:
A valve system of an overhead-camshaft-type internal combustion engine includes a cam holder fastened to a cylinder head having a combustion chamber formed therein. The cam holder supports a camshaft, and is disposed above the combustion chamber. The cam holder includes a bottom wall, a pair of oppositely-facing support walls having lower sides thereof joined with each other by the bottom wall, and a rib joining predetermined oppositely-facing portions of respective upper side portions of the support walls with each other. The support walls of the cam holder pivotally support the cam shaft. The rib may be integrated with the cam holder, or may be separately formed and fastened to the support walls of the cam holder.
摘要:
This invention provides an ultrasonic imaging system that implements imaging by distinguishing sharply and definitely the echo components generated by scattering in a microbubble contrast medium, from the tissue harmonic components generated by nonlinear propagation of a transmitted pulse. This ultrasonic imaging system, constructed to transmit/receive ultrasonic pulses to/from a living body and form a contrast image of the inside of the living body by using the contrast-imaging microbubbles, repeats the transmitting/receiving operations four times in all, under the same transmitting/receiving focus conditions at different phase angles [(a)=0°, (b)=120°, (c)=−120°, (d)=180°] of the carrier of a transmitted pulse wave including a common envelope signal, sums up three time-series receive echo signals associated with (a), (b), (c), forms the contrast image, sums up two time-series receive echo signals associated with (a), (d), forms an image of the living body having a nonlinear pulse propagation property, and makes a superimposed display of the two kinds of images.
摘要:
To provide an ultrasonograph capable of generating a transmission beam comprising a main beam having a uniform width over a wide range in an ultrasonic wave propagation direction by one-time transmission of an ultrasonic pulse. A weighted mean value of a plurality of transmission delay time values corresponding to focal lengths of transmission pulse waves having a plurality of focal points which are set in the ultrasonic wave propagation direction is calculated for each of elements constituting a transmission aperture and used as the delay time. Waves are actually transmitted with the weighted mean value as delay time. As the weight used for obtaining the delay time mean value, first, a transmission effective aperture width according to each transmission focal length is selected, and a weight in the direction of the transmit aperture realizing the width is calculated and is used in a focal length direction. As a result, the curvature of a wave front of a wave transmitted is close to that of the wave front of a short focal length in the center portion of the transmit aperture, and is close to that of the wave front of a long focal length in the peripheral portion. Consequently, a non-cylindrical wave front is formed. Thus, a transmission beam including a relatively narrow main beam with a uniform width over a wide range in the ultrasonic wave propagation direction can be generated by one-time transmission of an ultrasonic pulse.
摘要:
Provided is an ultrasonic diagnostic apparatus that constructs and displays a 3-dimensional elastic image showing the hardness or softness of a biological tissue of an object to be examined, and a method of displaying an ultrasonic image. The ultrasonic diagnostic apparatus is characterized by being provided with an elastic image constructing unit (24) that constructs 2-dimensional elastic image data on the basis of the strain or elasticity modulus acquired by the elasticity information calculating unit (23), an elastic volume data creating unit (26) that creates elastic volume data from plural sets of the 2-dimensional elastic image data, and 3-dimensional elastic image constructing unit (28) that constructs a 3-dimensional elastic image from the elastic volume data.
摘要:
To provide an ultrasonograph capable of generating a transmission beam comprising a main beam having a uniform width over a wide range in an ultrasonic wave propagation direction by one-time transmission of an ultrasonic pulse. A weighted mean value of a plurality of transmission delay time values corresponding to focal lengths of transmission pulse waves having a plurality of focal points which are set in the ultrasonic wave propagation direction is calculated for each of elements constituting a transmission aperture and used as the delay time. Waves are actually transmitted with the weighted mean value as delay time. As the weight used for obtaining the delay time mean value, first, a transmission effective aperture width according to each transmission focal length is selected, and a weight in the direction of the transmit aperture realizing the width is calculated and is used in a focal length direction. As a result, the curvature of a wave front of a wave transmitted is close to that of the wave front of a short focal length in the center portion of the transmit aperture, and is close to that of the wave front of a long focal length in the peripheral portion. Consequently, a non-cylindrical wave front is formed. Thus, a transmission beam including a relatively narrow main beam with a uniform width over a wide range in the ultrasonic wave propagation direction can be generated by one-time transmission of an ultrasonic pulse.
摘要:
An ultrasonograph capable of generating a transmission beam having a uniform width over a wide range in an ultrasonic wave propagation direction is provided. A weighted mean value of a plurality of transmission delay time values corresponding to focal lengths of transmission pulse waves set in the ultrasonic wave propagation direction is calculated for each element constituting a transmission aperture and used as the delay time for the element when waves are transmitted. As the weight used for obtaining the weighted mean value, a transmission effective aperture width according to each transmission focal length is selected, and a weight in the direction of the transmit aperture realizing the width is calculated and is used in a focal length direction.