摘要:
Members as an upper fixing screw, a piezoelectric element, a pressure transmitting member are located closer to region of an engine to be measured and the like than a fitting thread portion of a sensor casing so that a pre-stress on the piezoelectric element can be constantly maintained at a predetermined value, thus enabling pressure measurement with a high degree of accuracy. Further, a projecting portion or a spacer is provided on the backside of a pressure receiving surface in order to ensure the surface contact between the pressure transmitting member and the back surface of the pressure receiving surface, thus preventing the stress from concentrating on corners of the bottom surface of the pressure transmitting member.
摘要:
A sensor for detecting the combustion pressure of an engine, in which an upper fixing member and a casing are fixed while a pre-load is being applied to the upper fixing member, so that a pre-load may be applied to a piezoelectric element. Moreover, a tubular diaphragm for transforming a pressure into a strain and a pressure receiving face for receiving the combustion pressure are connected to each other through a plunger so that they may be kept away from each other.
摘要:
A piezoelectric pressure sensor includes a generally elongated sensor housing, a pressure receiving plate disposed at a first end of the sensor housing with a first surface thereof serving as a pressure receiving surface for receiving a pressure applied from outside of the sensor housing, a pressure transmission member accommodated in the sensor housing with a first end thereof held in contact with a second surface of the pressure receiving plate, and a tubular piezoelectric element accommodated in the sensor housing with a first end thereof held in contact with a second end of the pressure transmission member. A pair of electrodes are formed on the external and internal surfaces of the piezoelectric element, respectively. An external charge detection member is held in contact with the external electrode for collecting charge generated by the external electrode and is encircled by a heat-shrinkable tube, while an internal charge detection member is held in contact with the internal electrode for extracting charge therefrom. A fixing screw is threaded into the sensor housing for holding in a prestressed fashion the piezoelectric element and the pressure transmission member against the pressure receiving plate. During assemblage of the pressure sensor, the heat-shrinkable tube undergoes a thermal shrinkage upon application of heat thereto, thereby compressing the external charge detection member radially inwardly against the external electrode.
摘要:
A piezoelectric pressure sensor is provided with a sensor housing including an inner sensor housing, accommodating an piezoelectric element, and an outer sensor housing threaded to a test article. The inner sensor housing is attached to the outer sensor housing in such a manner that a prestress applied to the piezoelectric element does not change due to an axial strain in the outer sensor housing. The axial strain is produced when the outer sensor housing is mounted to a test article.
摘要:
The present invention relates to a skutterudite thermoelectric material for directly converting heat generated by the Seebeck effect into electricity, and provides a method of producing a Co—Sb-based filled-skutterudite sintered material having a lower thermal conductivity and thereby having a higher figure of merit. The crystal grains of a Sb-containing skutterudite compound and a metal oxide dispersed in the crystal grain boundaries are sintered to obtain the skutterudite thermoelectric sintered material. The metal oxide prevents growth of grains in the process of sintering, whereby the skutterudite compound is finely pulverized to have an average crystal grain size of 20 &mgr;m or less. As a result, the areas at the boundaries of the fine crystal grains are increased, phonon scattering is enhanced, the thermal conductivity is decreased, and the figure of merit is increased. The metal oxide is an oxide of a rare earth metal. The skutterudite compound includes a filled-skutterudite compound having a composition of LnyFexCo4−xSb12 (Ln: a rare earth metal, 0
摘要:
The present invention relates to a thermoelectric material containing CoSb.sub.3 compound for converting heat to electricity, and provides a p-type thermoelectric material of CoSb.sub.3 having a high power factor by achieving high Seebeck coefficient consistently with high electric conductivity in a material of CoSb.sub.3 system without causing increase in heat conductivity. By sintering Co.sub.0.07 Pt.sub.0.03 Sb.sub.3 alloy powder using the spark plasma sintering technique, the material is densified, while growth of grains is restricted, so that a higher electric conductivity is achieved with a heat conductivity maintained in a low level, and the figure of merit as a heat-transfer material is improved. Also, by providing such heat insulating layer as an oxide intermediately in a grain boundary of a compound of CoSb.sub.3 in a sintered body, the heat conductivity is reduced. Further, the Seebeck coefficient is increased by adding a rare earth metal to the thermoelectric material of CoSb.sub.3, and allowing it to be precipitated in grain boundaries of the sintered body.
摘要:
In an electrode-membrane-frame assembly production method, a principal part is formed by an electrolyte membrane, first and second catalyst layers and first and second gas diffusion layers, with the first and second gas diffusion layers arranged with their outer circumferences at different positions. The principal part is arranged in a molding die with a circumferential region of the principal part disposed on a flat region of a primary molded body. A circumferential portion of one of the gas diffusion layers is arranged to oppose a flat region of the primary molded body so that the membrane is interposed between the circumferential portion and the flat region. Subsequently, a secondary molded body is formed to integrate with the primary molded body and the principal part.
摘要:
A cell stack of a fuel cell comprises a cell stack body including a cell stack structure including plural cells stacked together; an elastic member disposed at an end of the cell stack structure in a direction in which the plural cells are stacked, and a pair of end plates sandwiching the cell stack structure and the elastic member, and a fastener band extending to surround the cell stack body and to cover a pair of end surfaces and a pair of opposing side surfaces of the cell stack body, the fastener band including a first band engagement portion and a second band engagement portion at both end portions thereof, respectively, and the cell stack body is fastened by the fastener band by direct or indirect engagement between the first band engagement portion and the second band engagement portion.
摘要:
A fuel cell separator having a turn portion of a serpentine-shaped reaction gas passage region. In the turn portion, a recessed portion is defined by an outer end of the turn portion and oblique boundaries between the recessed portion and a pair of passage groove group. In the turn portion, a plurality of protrusions, which vertically extend from a bottom face of the recessed portion and are arranged in an island form, are disposed such that one or more protrusions form a plurality of columns lined up and spaced apart from each other with a gap in a direction in which the outer end extends and one or more protrusions form a plurality of rows lined up and spaced apart from each other with a gap in a direction perpendicular to the direction in which the outer end extends.
摘要:
A polymer electrolyte fuel cell is provided with a fuel cell stack assembled by sandwiching a plurality of stacked single cell modules with a plurality of fastening members through a pair of end plates. The fuel cell includes a first elastic member arranged between the fastening member and the end plate and a plurality of second elastic members arranged between the end plate and the end of the fuel cell stack. Each of the second elastic members is arranged on the surface of the end plate corresponding to the electrode portion of a membrane electrode assembly in each of the single cell module, and each of the first elastic members is arranged on the surface of the end plate corresponding to a seal member arrangement region in which the seal member is arranged between the periphery of the membrane electrode assembly and a pair of separator plates in each single cell module.