720results about How to "Reduce stress" patented technology

The invention belongs to the technical field of steering pull rod design, and particularly relates to a steering pull rod mechanism design method based on analytic geometry and a steering pull rod mechanism. The steering pull rod mechanism is simplified into a plane connecting rod mechanism, and four key hinge points are marked; establishing a coordinate system by taking P1 as an original point; the length, the initial angle and the P4 coordinate of the front steering swing arm are obtained; calculating two coordinates of a P2 point when the front steering swing arm rotates to a limit position; generating P2 ''and P2'' ''points by rotating P2 'P4 and P2'' P4 line segments; and connecting the line segments and constructing perpendicular bisectors, and determining the position of a P3 point by solving the intersection point of the perpendicular bisectors. According to the method, the steering pull rod mechanism is designed through analytic geometry and coordinate transformation, the accuracy of hinge point positioning is improved, and structural deviation caused by empirical estimation is reduced; the design complexity is reduced through standardization steps, the development period is shortened, the motion coordination of the steering system is optimized, and the method is suitable for the field of automobile chassis and the like needing high-precision motion control.

The utility model discloses a kind of foundation structure and wind turbine generator set of wind turbine generator set, it is related to wind power generation technical field, wherein, foundation structure includes first bearing platform, second bearing platform, multiple bored piles and multiple anchor rods, the top surface of first bearing platform is connected with the connecting cylinder for connecting the tower cylinder of wind turbine generator set;Second bearing platform is set below first bearing platform, the top surface of second bearing platform projects the bottom surface of first bearing platform and forms step surface, the vertical projection of the bottom surface of first bearing platform in second bearing platform forms core area, the edge of second bearing platform forms the expansion area surrounded in core area;Multiple bored piles are distributed in core area with interval, each bored pile extends downward from the bottom surface of second bearing platform, and bored pile is vertically arranged;Multiple anchor rods are distributed in expansion area with interval, and anchor rod extends downward from the bottom surface of second bearing platform and is arranged with inclination.The foundation structure has good bearing capacity and stability, can guarantee the safety and stability of wind turbine generator set in long-term operation process.

The utility model discloses a sleeve repair tool for a fuel manifold of a turboshaft engine, which comprises a support with the top end provided with a penetrating column with threads on the inner wall, and further comprises a threaded pressing rod with the top end provided with a pulling rod, and the threaded pressing rod is in threaded connection with the penetrating column through the threads on the outer wall; a semi-arc-shaped pressing plate is arranged at the bottom of the T-shaped sliding block, and the T-shaped sliding block is movably connected with the threaded pressing rod; a shape correcting arc plate is arranged on the positioning column opposite to the semi-arc pressing plate, and the positioning column is located at the middle section of the support; and the gland is connected to the positioning column through a bolt. According to the sleeve repairing tool for the turboshaft engine fuel main pipe, the problems that in the prior art, manual positioning is not accurate, and pipe wall cracks and internal threads are prone to being crushed to be scrapped due to repeated knocking are solved.

The application provides a kind of bionic artificial stomach device based on electrostatic hydraulic drive and its application, belong to bionic medical instrument technical field.The device includes flexible bionic stomach cavity, composite peristaltic wave drive module including multiple electrostatic hydraulic drive units and programmable control module.Programmable control module applies high voltage electric signal to each electrostatic hydraulic drive unit according to preset timing, drive flexible bionic stomach cavity outer wall to produce continuous, distributed surface contraction deformation, to form annular advancing peristaltic wave propagating from fundus to antrum.The application realizes continuous surface driving of flexible interface through electrostatic hydraulic effect, solves the problem of unreasonable contact mode, discontinuous peristalsis and mechanical distortion in the prior art, improves the physiological relevance of in-vitro simulation of gastric mechanics, digestion process and drug transport.

This application provides a vertical heat recovery coke oven waste heat exchange unit, waste heat utilization system, and method, using supercritical carbon dioxide as the heat exchange medium. The unit includes a main compressor, a regenerator assembly, a high-pressure turbine, a low-pressure turbine, a precooler, and a heat exchanger. The heat exchanger internally houses a high-temperature superheater, a high-temperature reheater, a low-temperature superheater, a low-temperature reheater, an air-cooled wall, and an economizer. The main compressor outlet is connected to the cold-side inlet of the regenerator assembly, and the cold-side outlet of the regenerator assembly is connected to the working fluid inlet of the heat exchanger. The working fluid flows sequentially through the economizer, the air-cooled wall, the low-temperature superheater, and the high-temperature superheater before entering the inlet of the high-pressure turbine. The high-pressure turbine outlet is connected to the inlet of the low-temperature reheater, the low-temperature reheater outlet is connected to the inlet of the high-temperature reheater, and the high-temperature reheater outlet is connected to the inlet of the low-pressure turbine. The low-pressure turbine outlet is sequentially connected to the hot side of the regenerator assembly, the precooler, and the main compressor inlet.

The utility model relates to a kind of MEMS accelerometer, including substrate and multiple sensitive structures being set on the substrate, multiple the sensitive structure is connected by elastic coupling beam structure each other between, each the sensitive structure includes mass and the sensitive capacitor being set on the mass, the mass of adjacent two the sensitive structure is connected by the elastic coupling beam structure each other.The MEMS accelerometer provided by the utility model solves the problem that the existing MEMS accelerometer improves sensitivity and signal-to-noise ratio and leads to the problem of large spring beam thermal stress.

The utility model discloses a propeller wind speed sensor base stable support relates to propeller wind speed sensor technical field, including the hoop unit including the arm of clamping, fixed plate and the top silk, the support unit includes slide rail, slide plate and the support block, the utility model discloses the auxiliary support of support unit and hoop unit on the base, jointly constitute stable triangle force transmission path, and the stress peak value and reciprocating bending moment that sensor base bears are reduced greatly to the significant inhibition that the persistence of the shaking caused by wind induced vibration is inhibited, in addition, make the slide on the slide plate, and the locating column inserts into the tail cylinder clamping groove, and the rotation freedom degree of tail cylinder around its axis can be limited, prevent the change of sensor pointing because of vibration, collision or unintentional touch, ensure that the initial wind direction reference of every time power use is consistent with the calibration value.

The application provides a combined guide vane and a ship, which achieves the basic requirement of improving the flow field around the stern and propeller and improving the propeller efficiency, reduces the stress on the structure by arranging the guide vanes in the axial direction, increases the energy saving effect, and avoids the negative influence of the axial misalignment arrangement on the propeller pulsating pressure by aligning the end. In addition, by limiting the circumferential length of the guide vane, the resistance generated by the device is small, that is, the resistance and structural performance of the energy saving device are improved; through the combination of various schemes of the guide vane, the guide vane, the connecting piece and the flow guide fin, and the establishment of the design method matched with each combination of the application, the optimal energy saving effect can be achieved for different ship types and navigation conditions, the effective complementation among multiple structures is realized, and the universality is strong.

The invention relates to the technical field of reactors, in particular to a kneading-pressing type mixing reactor based on hydraulic drive and a working method, and the kneading-pressing type mixing reactor comprises a mixing cavity section module, a power source module and a microcontroller. Wherein the mixing cavity section module is provided with a flexible inner container used for containing materials, a plurality of independent flexible driving cavities are arranged outside the mixing cavity section module, and the mixing cavity section module comprises at least one annular cavity section and a base cavity section; the power source module conveys or recycles a working medium to each driving cavity through a pipeline system with an independent control valve and drives the driving cavities to expand or contract, so that local extrusion force is applied to the wall surface of the flexible liner from the outer side; the microcontroller controls all the valves to act according to a preset strategy and drives all the cavity sections to act cooperatively, so that the flexible inner container generates non-rotating modeling deformation kneading and pressing actions, three-dimensional mild mixing of materials is achieved, the safety risk of rotating components is fundamentally eliminated, and the problems that high-viscosity materials are poor in mixing uniformity and mixing heat release is difficult to remove rapidly are solved.

This utility model discloses a mud crab spawning and hatching device, including a cement pool, which comprises a pool body with a permeable stone slab at the bottom. A hole is opened at the bottom right side of the pool body, and a drain pipe is installed inside the hole. A water supply component includes a water quality sensor located on the left side of the pool body. An air supply component includes a dissolved oxygen sensor located at the front of the pool body. A heating component includes a temperature sensor located at the front of the pool body. A movable component is installed at the top of the pool body, with a polycarbonate panel fixedly connected to its inner side. This utility model, through the structural design of water quality, dissolved oxygen, and temperature sensors, combined with water supply, air supply, and heating systems, can monitor and adjust key environmental parameters in the hatching pool in real time. The water quality sensor, linked to a solenoid valve, intelligently changes water to prevent water quality deterioration. Microporous aeration heads uniformly increase oxygen, ensuring balanced dissolved oxygen distribution. Heating pipes, in conjunction with the temperature sensor, maintain a stable water temperature.

This utility model belongs to the field of terminal block technology, specifically relating to a rotatable terminal block, including a terminal base, a terminal head, and a shaft. The terminal base includes a base plate and a connecting portion, the connecting portion being integrally formed with the base plate. The terminal head includes a connector at the head end and a wire clamping barrel at the tail end, the connector being integrally formed with the wire clamping barrel, and a wire groove being formed on the wire clamping barrel. The connecting portion and the connector are connected by a shaft, and the terminal head and the terminal base can rotate relative to each other in a horizontal or vertical plane. The terminal block of this solution can rotate freely in a horizontal or vertical direction, and different rotation directions of the terminal block can be selected according to the situation at the moving parts.

The application provides a kind of integrated node flexible variable mechanism of rope drive active deformation topology structure, it is related to flexible deformation device technical field, control is realized to large-span deformable structure by using rope drive, structural weight is reduced, and the operating performance of flexible deformation body mechanism is improved.The shortening of first winding makes the radius of annular framework larger;The shortening of second winding makes the length of annular framework longer;Between the first annular framework and the second annular framework, the first winding on the first annular framework is arranged on the first node on the second annular framework, and the second winding on the first annular framework is arranged on the first node on the second annular framework to realize active turning, which can reduce the stress applied to the mechanism by the outside when the pipeline moves, help protect the flexible structure, improve the system use time, and better adapt to complex terrain space scenarios, actively adjust the travel speed and direction to select the optimal path to improve work efficiency.

The utility model relates to water bird weighing technical field especially relates to a kind of shorebird water bird weighing device.The shorebird water bird weighing device includes: weighing sensing device, U-shaped pipe, baffle, limiting component, assembly component, the front side of weighing sensing device is equipped with display screen, the top of weighing sensing device is equipped with pressure scale, the top of pressure scale is fixedly connected with bearing block symmetrically, the top of bearing block is symmetrically provided with jack, U-shaped pipe is placed in the top of jack, the bottom of U-shaped pipe is fixedly connected with two insertion rods, the side of two insertion rods is provided with engagement slot, the inner wall of U-shaped pipe middle end is fixedly connected with baffle, the left and right two sides inner wall of U-shaped pipe is hinged with hatch, the outside of U-shaped pipe is provided with multiple through holes.The utility model makes water bird more easily calm in familiar touch feeling environment, reduces struggle and ramming, avoids subsequent measurement interference due to odor residue, improves adaptability and weighing efficiency, guarantees water bird safety and operation efficient.

The utility model relates to the technical field of furniture provides a zero gravity chair frame, and zero gravity chair frame includes fixed seat, linkage and screw rod mechanism, and linkage is equipped with backrest structure and leg support structure, and screw rod mechanism sets up in fixed seat, and screw rod mechanism includes transmission screw rod, wherein, the leg support structure and fixed seat between being equipped with connecting rod structure, and connecting rod structure has first angle and second angle, at first angle, backrest structure and leg support structure draw together relative to fixed seat, at second angle, backrest structure and leg support structure unfold relative to fixed seat, and connecting rod structure supports leg support structure. By connecting rod structure bears the pressure in the up and down direction, thereby reduced transmission screw rod's stress. The above design is favorable to avoid transmission screw rod reciprocating extension and shortening in the horizontal rhythm process, solves the problem that backrest structure and leg support structure alternate up and down and swings, and reduces the noise, guarantees the overall stability when rhythm seat horizontal rhythm again, significantly promotes the experience.

The application discloses a multi-direction stirring and mixing device for fireproof paint production, which comprises a main machine, two Y-shaped universal rocker arms symmetrically arranged on the inner side of the main machine, a mixing cylinder for storing raw materials arranged between the two Y-shaped universal rocker arms, and a driven assembly arranged between the outer wall of the mixing cylinder and the arm rod of the Y-shaped universal rocker arm. The multi-direction stirring and mixing device is connected with the arm rod through the toothed rod, the multiple tooth surfaces of the toothed rod share the alternating load which changes in size and direction with time, the contact stress concentration of a single tooth surface is reduced, the stress state of the traditional pin shaft which is prone to fatigue micro-cracks due to the concentration of alternating shear stress and bending stress in a local part is avoided, meanwhile, the movement track distortion and stress deterioration of the mixing cylinder caused by the wear and wear gap increase of the traditional pin shaft are reduced, and the later maintenance work is facilitated.

This invention belongs to the field of casting cutting technology, and mainly relates to a cutting method for preventing cracking of nickel-based superalloy castings. It changes the cutting process and process control parameters in existing technologies, providing a complete and effective cutting method. It strictly controls the parameter values ​​of key nodes in each cutting step, avoiding the casting from passing through the brittle phase precipitation temperature range, improving the casting's plasticity and toughness, reducing stress, and preventing crack formation. The casting undergoes annealing after molding to eliminate casting stress, providing a better cutting condition for subsequent riser cutting. The cutting method provided by this application effectively prevents casting cracking during cutting, making casting manufacturing quality controllable and reducing rework costs. After annealing, the elongation is significantly increased by about 500%, and the plasticity is significantly improved, effectively reducing the risk of cracking.

This utility model provides a pile head reinforcement structure for construction in hard rock formations, including a steel sleeve, a grouting structure disposed between the steel sleeve and the outer surface of the pile head, a shear structure for forming a mechanical interlocking effect between the pile head and the steel sleeve, an anchoring structure for reliable connection with the pile body, a pressure-bearing flange disposed at the bottom of the steel sleeve, and a reinforcing rib structure arranged on the outer wall of the steel sleeve. The steel sleeve is fitted around the periphery of the precast pile head, and the grouting structure fills the space between the inner wall of the steel sleeve and the outer surface of the pile head and is fixed to both. This pile head reinforcement structure for construction in hard rock formations solves the problem that, due to the lack of effective structural reinforcement and circumferential restraint measures for precast pile heads in related technologies, pile heads are prone to spalling, crushing, cracking, and other damage under high loads and impact conditions.

The utility model provides a counter-pull pushing device which comprises a fixed end, a push rod, a push rod, a push rod, a push rod and a push rod, the pushing end is used for applying pushing force to the direction of the fixed end; and the counter-pulling mechanism comprises a counter-force frame and a force transmission piece, the counter-force frame is arranged on the side, opposite to the fixed end, of the pushing end and makes contact with the pushing end, one end of the force transmission piece is installed and fixed, and the other end of the force transmission piece is connected with the counter-force frame. According to the counter-pulling and pushing equipment, the pushing end and the counter-pulling mechanism are arranged in a split mode, so that the requirement for the structural rigidity of the pushing end of the counter-pulling and pushing equipment is lowered, the pushing end is protected, and the production cost is lowered.

The application discloses a lithium-free high-heat-resistant ceramic mud and a preparation method thereof, and relates to the technical field of ceramic materials. In the preparation of the lithium-free high-heat-resistant ceramic mud, alumina is reacted with 3-(2,3-epoxypropoxy) propyl trimethoxysilane to obtain pre-modified alumina; the pre-modified alumina is reacted with starch to obtain modified alumina; ethyl acetoacetate, isopropyl alcohol, zirconium oxychloride, aluminum sec-butoxide, polyvinylpyrrolidone and N-N dimethylformamide are mixed to form a spinning solution, the spinning solution is electrospun, and then immersed in yttrium oxide sol to obtain alumina-zirconia-yttria composite fibers; the modified alumina, talc, alumina-zirconia-yttria fibers, hydroxypropyl methyl cellulose, glycerol, oleic acid, polyethylene glycol and water are stirred and mixed, and vacuum pugging is carried out to obtain the lithium-free high-heat-resistant ceramic mud. The lithium-free high-heat-resistant ceramic mud prepared by the application has good thermal shock resistance and bending strength after sintering.

The application discloses a high-aluminum-titanium heavy-duty combustion turbine vane crack repairing and tissue recovering method, and belongs to the field of heavy-duty combustion turbine vane repairing. The method adopts a repairing process route of complete solid solution heat treatment-welding repair-partial solid solution heat treatment-aging heat treatment, melts the matrix gamma' strengthening phase through complete solid solution heat treatment, reduces the volume fraction of the gamma' phase, reduces the liquefaction crack sensitivity, and improves the weldability of the matrix; the matrix surface layer crack of the turbine vane is completely exposed through complete solid solution heat treatment, the turbine vane crack repairing qualified rate is improved, the IN625 welding wire with low aluminum titanium content is used in the welding stage, the strengthening phase in the weld heat affected zone in the welding process is reduced, and the crack tendency of the weld is reduced; and the matrix gamma' strengthening phase is recovered through aging heat treatment. The method can effectively solve the heavy-duty combustion turbine vane crack repairing process of the high-aluminum-titanium turbine vane, and effectively improves the high-aluminum-titanium turbine vane repairing qualified rate.

The utility model discloses a lamp arm type metal plate solar street lamp which comprises a lamp post, a lamp body and a solar module, the solar module is fixed to the top of the lamp post, and the lamp body is fixed to the lamp post through a lamp arm fixedly connected with the lamp body and located at the bottom of the solar module. The lamp body comprises a lamp shell, a lamp cover and a light-emitting module arranged in the lamp shell, the lamp arm, the lamp shell and the lamp cover are all made by adopting a sheet metal process, the rear end of the lamp shell is provided with a mounting hole for the front end part of the lamp arm to enter, the lamp shell is internally provided with a locking mechanism fixed with the lamp shell, and the locking mechanism is connected with the lamp body. The locking mechanism locks the front end portion of the lamp arm, and the lamp cover completely covers and seals the lamp shell. According to the lamp arm type metal plate solar street lamp, the lamp arm and the lamp shell are manufactured through the metal plate technology, the light-emitting module is supported through the lamp shell of a light structure, materials used for the lamp body and the lamp arm can be greatly reduced, and then the total weight of the street lamp is reduced.

The application relates to the field of vehicle technology and discloses an all-terrain vehicle, which comprises wheels, a power source, a front axle assembly and an input shaft. The wheels comprise front wheels and rear wheels. The power source drives the wheels to rotate. The front axle assembly is connected with the front wheels. The input shaft is connected with the front axle assembly and the power source. The front axle assembly comprises a driven device, an output gear, a first connecting wheel, a second connecting wheel and a friction assembly. The driven device comprises a fixedly connected driven gear and an inner housing. The output gear drives the front wheels. The first connecting wheel is engaged with the output gear. The second connecting wheel is engaged with the inner housing. The locking mechanism can drive the friction assembly to switch between a compression state and a free state. When the friction assembly is in the free state, the friction resistance between the output gear and the driven device is smaller than that when the friction assembly is in the compression state. The friction torque of the friction assembly is increased, the assembly efficiency of the friction assembly is improved, and the size of the transmission assembly is reduced.

The application provides a swept-back three-beam thin wing composite wing structure, which comprises a wing main body and an aileron installed in a wing main body mounting groove, the wing main body comprises a wing skeleton and a wing outer skin structure outside the wing skeleton; the wing skeleton comprises a longitudinal member unit and a transverse member unit, the longitudinal member unit comprises a front beam, a middle beam and a rear beam, the front beam and the middle beam and the middle beam and the rear beam are arranged at acute angles, the transverse member unit comprises a plurality of wing ribs arranged between the front beam and the middle beam, between the middle beam and the rear beam and on one side of the front beam towards the front of the fuselage; the front beam, the middle beam and the rear beam are all provided with a spar connecting head for connecting with the fuselage. The wing provided by the application adopts a three-beam structure, each wing beam has a mouth-shaped cross section, so that each wing beam forms a multi-wall form, can bear the bending moment and the torque brought by a large wing effective load, and the wing structure is light in weight, high in strength and good in integrity.

This invention provides a microgap suspension device and a microgap inverted suspension heat treatment process, comprising the following steps: adding p-aminobenzenesulfonic acid to a solvent, mixing thoroughly, and then adding carbon nanotubes to obtain a carbon nanotube dispersion; stirring the carbon nanotube dispersion under heating conditions to obtain a p-aminobenzenesulfonic acid-modified carbon nanotube dispersion; coating a substrate surface with a lead bromide solution, then coating the lead bromide surface with a cesium bromide solution, then coating the cesium bromide surface with the p-aminobenzenesulfonic acid-modified carbon nanotube dispersion; and finally performing heat treatment through a microgap suspension device to form a photoactive layer film. The microgap inverted suspension heat treatment process of this invention, through controllable height suspension heat treatment, ensures that the film is almost unconstrained by the rigidity of the substrate during thermal expansion and cooling contraction, thus making it suitable for flexible substrates as well. It also avoids direct contact damage to flexible substrates during high-temperature heat treatment.

The invention relates to the technical field of sodium-ion batteries, in particular to a sodium-ion battery positive electrode material and a preparation method thereof. The sodium ion battery positive electrode material is Ti and Cl doped Na4VMn (PO4) 3, and the molar ratio of Na to Ti in the sodium ion battery positive electrode material is 4: (0.05-0.1); the molar ratio of Na to Cl is 4: (0.05-0.1). According to the sodium-ion battery positive electrode material provided by the invention, a titanium element and chlorine element synergistic co-doping mode is adopted, so that the ginger-Taylor distortion caused by manganese ions in the charging and discharging process can be inhibited, the lattice stress can be reduced, and the stability of the material structure can be enhanced; meanwhile, the dissolution of manganese under a high-rate cycle condition can be inhibited, and the loss of active substances and the side reaction of electrolyte are reduced, so that the electrochemical stability and the structural integrity of the electrode material are improved, and the sodium ion battery containing the positive electrode material has relatively high specific capacity, excellent rate capability and cycle stability.

The invention relates to the technical field of power electronic direct-current converters, in particular to an input and output common-ground high-gain boost converter which comprises a direct-current voltage source Vin, diode components D0-D4, capacitor components C0-C4, a first coupling inductor L1, a second coupling inductor L2, a first mosfet tube S1, a second mosfet tube S2 and a resistor R. The two main loops operate in a staggered mode, so that input current is continuous, input current ripples are small, relatively stable energy is continuously provided for the circuit, the voltage multiplication unit is adopted, the amplification factor of the circuit is increased, the duty ratio of the mosfet tubes S1 and S2 is adjusted, and small current ripples can be kept even under the condition that the boost factor is large. The device has the advantages of high step-up ratio, low device stress, high efficiency, easiness in control and implementation, lower cost and the like, and is suitable for a new energy power generation scene needing high direct current bus voltage grid-connected output under a low input voltage condition.

This invention relates to a method for preparing high-performance aluminum alloy radiator plates. The method involves controlling the iron-silicon ratio of the main impurity component in the melt to be no less than 1.9 to reduce internal cracks in the cast billet and decrease the machining deformation rate of the finished product. This is achieved by adding aluminum-titanium alloy and a grain refiner in the furnace and online runner, while ensuring that the titanium content in the aluminum alloy ingot is maintained within a reasonable range, resulting in an ingot grain size ≤1. This improves the mechanical properties, uniform microstructure, and refined grains of the aluminum alloy radiator plate. Simultaneously, a small amount of copper is added, and the final rolling temperature is controlled at 330-360℃, resulting in fully recrystallized grains within the aluminum alloy plate. This improves the strength of the aluminum alloy radiator plate while eliminating anisotropy in its internal mechanical properties and reducing internal stress, ultimately yielding a high-performance aluminum alloy radiator plate.

This utility model provides a fireproof sealing structure for steel structures, belonging to the field of building engineering technology. It solves the technical problems of poor fire resistance, poor durability, and poor aesthetics in existing technologies. The fireproof sealing structure for steel structures includes a floor slab and connected steel beams. The floor slab and steel beams are respectively provided with cable perforations for floor cables and steel beam cables. Cables are threaded through these perforations, and annular movable gaps are provided between the cables and the perforations. Fireproof sealing rings for the floor slab and steel beams are respectively provided between the cable perforations and the cables to seal their respective annular movable gaps. Both the fireproof sealing rings have expansion joints that can seal and prevent the force of cable swaying from being transmitted to the respective floor slab and steel beam. This utility model has the advantages of strong fire resistance, good aesthetics, and high durability.

A capacitor structure includes lower and electrodes, and a capacitor dielectric film interposed therebetween. The lower electrode includes a lower electrode film including a first metal element, a first doped oxide film including a second metal element and an oxide of the first metal element, and a first metal oxide film. The first metal oxide film includes an oxide of the first metal element and is free of the second metal element. The upper electrode includes an upper electrode film including the first metal element, a second doped oxide film including the second metal element and an oxide of the first metal element, and a second metal oxide film that includes an oxide of the first metal element, and is free of the second metal element.