摘要:
The invention provides a thermal type flow meter which has a high reliability and a low cost. In a thermal type flow meter provided with a flow rate detecting element in which at least a heat generating resistor and a lead electrode are formed on a surface of a tabular substrate, and a support body in which a concave portion accommodating the flow rate detecting element is formed on a surface, and in which the flow rate detecting element is firmly fixed and accommodated by an adhesive agent in a back surface of the tabular substrate and a part of a bottom surface of the concave portion, an approximately straight discharge groove which is deeper than a bottom surface of the concave portion and passes through both end surfaces in upward and downward sides of the concave portion is formed from the upstream side of the support body concave portion to the downstream side, between the cavity of the tabular substrate and the back surface region of the tabular substrate in which the lead electrode is formed. Accordingly, it is possible to achieve the thermal type flow meter which has the high reliability and the low cost.
摘要:
The object of this invention is to provide a heated type air flow rate sensor for measuring an air flow rate using heat generating resistive element or resistor formed within a diaphragm of which periphery is fixed, in which diaphragm destruction due to the collusion of dust is adapted to be prevented. Tapers of two or more stages are formed at a diaphragm fixing flange, and the angle of the most inside taper is made smaller than the angle of the taper which is outside with respect to the most inside taper. When dust collides with the diaphragm and the kinetic energy is transformed into distortion energy, the diaphragm destruction is avoided by making small the slope of the load-displacement curve at the neighborhood of the diaphragm flange to make the generated load small.
摘要:
A gas flow measuring apparatus includes a detecting element including a heating resistor and a thermo-sensitive resistor disposed on a diaphragm and external terminals connected to the heating resistor and the thermo-sensitive resistor, and a flow rate detecting unit which controls heating temperature of the heating resistor and which detects a flow rate of gas according to a change in a resistance value of the heating resistor or the thermo-sensitive resistor. The detecting element includes a resistor area in which the heating resistor and the thermo-sensitive resistor are formed and a fixed section area in which the external terminals are formed. A stress mitigating unit is formed between the resistor area and the fixed section area.
摘要:
By sealing a diaphragm with less processes and lower cost and reducing deformation due to remaining stress, a stable and highly reliable pressure sensor construction is proposed. The pressure sensor is low in measurement error and small in floating capacitance and leakage current and good in characteristic. As a means to attain the above object, a polycrystalline silicon diaphragm is sealed with a silicon oxide film deposited through a LPCVD method and then completely covered. The diaphragm is placed on a surface of a semiconductor substrate with a nearly constant gap of 0.15 to 1.3 μm, and has difference-in-grade constructions of a deformation reducing means due to remaining stress.
摘要:
In a capacitance type pressure sensor, a diaphragm is formed of a fragile material using an impurity-diffused monocrystal silicon and constitutes a stable pressure-responsive structure which does not undergo a plastic deformation. Between the diaphragm and a movable electrode is formed an oxide film to diminish stray capacitance between the movable electrode and a substrate and also between the movable electrode and a impurity-diffused layer. The oxide film and the movable electrode are each divided into plural regions so that the divided regions of the movable electrode are formed on the divided regions of the oxide film, thereby diminishing stress strain induced by a difference in therm expansion coefficient among the diaphragm, oxide film and movable electrode. The upper surface of a fixed electrode is covered with a structure for the fixed electrode which structure is formed by an insulating polycrystal silicon film not doped with impurity whereby the rigidity of the electrode is enhanced and it is possible to diminish a leak current.
摘要:
A cylinder pressure sensor is adapted to detect a cylinder pressure by detecting a change in the amount of light being transmitted through an optical fiber in an axial direction. Two support portions support the optical fiber at two points along the length thereof. A diaphragm in contact with the optical fiber causes bending of the optical fiber in dependence upon a change in the cylinder pressure. The position at which a force is applied against the optical fiber by the diaphragm is deviated from a center position between the two support portions. The resulting cylinder pressure sensor is capable of accurately measuring cylinder pressure and knocking over a long period of time with a low cost and reduced initial variations.
摘要:
A semiconductor substrate has a major surface, another major surface on the opposite side of the first major surface, a strain gauge stripe formed in the central portion of the second major surface by diffusing an impurity therein, and electrodes connected to the strain gauge stripes. These strain gauge stripes are spaced from the peripheral edge of the second major surface by a distance greater than 1/3 of the length of the same major surface. The first major surface of the semiconductor substrate is bonded to an elastic metal load plate.
摘要:
In a structure in which peripheral part of a diaphragm section of an electrical insulating film is covered with a protective film made of an organic material, the resistor wire on the diaphragm section crosses the peripheral part of the diaphragm section. At a place where a narrow wire of a resistance temperature detector and the like crosses the peripheral part of the diaphragm section, the protective film is thinner than the other part, and the dust impact resistance is reduced. At a place where a heating resistor wire connected to a heating resistor body or resistance temperature detector wires connected to resistance temperature detector bodies cross a periphery of the diaphragm section, a film component protruding from an electrical insulating film is arranged side by side with the heating resistor wire or the resistance temperature detector wires.
摘要:
An air flow measuring instrument, comprising: an auxiliary passage 8 arranged inside a main passage through which fluid flows, a tabular member 5 on which a pattern of a heating resistor for measuring an air flow is provided on one face 5a, the tabular member being disposed inside the auxiliary passage so that the one face 5a on which the heating resistor pattern of the tabular member is provided is disposed along a flow of fluid inside the auxiliary passage 8, a heating resistor pattern-side fluid passage 8a portion formed so that the fluid flows between the face 5a and a passage-forming surface 8d of the auxiliary passage, and a back-surface 8b side fluid passage portion formed so that fluid flows between a face 5b on a side opposite to the face of the tabular member and the passage-forming surface of the auxiliary passage. Guidance portion 13 guiding dust that collides against the end portion to back-surface side fluid passage portion 8b side is provided on upstream-side end of tabular member.
摘要:
A heating resistor type flow measuring device comprising a housing having a support part provided between a frame body and a connector and connected to the mounting part of a fluid passage, a flow rate detection element held on the frame body side of the housing, and an electronic circuit held on the housing and connected electrically to the flow rate detection element and the connector, wherein the electronic circuit is held on the frame body side of the housing and positioned in the fluid passage, a member with the rigidity higher than the material of the main structural member of the housing is formed integrally with the support part, the housing is fixed to the fluid passage through the member with high rigidity. A metal plate is inserted into the support part so as to increase rigidity. Further, a distance is provided between the support part and a metal plate forming a route for conducting the heat transferred to the metal base fixing an electronic circuit substrate by a plastic mold so as to form a structure obstructing a heat transfer, or a clearance is provided in a portion spaced by the plastic mold between the support part and the metal base so as to form a structure obstructing a heat transfer.