115results about How to "Reduce local stress concentration" patented technology

A semiconductor device (100) comprises a first resin substrate (101) on which a first semiconductor chip (125) is mounted a surface thereof; a second resin substrate (111) on which a second semiconductor chip (131) is mounted on a surface thereof; and a resin base material (109), joined to a front surface of the first resin substrate (101) and to a back surface of the second resin substrate (111), so that these surfaces are electrically connected. The resin base material (109) is disposed in a circumference of the first resin substrate (101) in the surface of the first resin substrate (101). Further, the first semiconductor chip (125) is disposed in a space section provided among the first resin substrate (101), the second resin substrate (111) and the resin base material (109) in the surface of the first resin substrate (101).

The present invention is directed to a delivery catheter for use in deploying a vascular prosthesis having a self-expanding helical section for use in a wide range of interventional applications. The delivery catheter comprises an elongated member having a helical ledge with a pitch selected to impose a predetermined amount of foreshortening on the vascular prosthesis during deployment. Methods of making and using the delivery catheter of the present invention also are provided.

A gas turbine engine is provided with an airfoil component that is disclosed as a turbine blade. Internal cooling passages circulate air within the blade. An impingement rib separates a cooling air channel from a pedestal array, and includes cross-over holes to meter the flow of air into the pedestal array. A lower end of the impingement rib is split to reduce stress concentrations between the impingement rib and a platform. Further, the pedestals adjacent to the lower end of the impingement rib are formed to be stubs, which do not extend entirely across a width of the blade. The disclosed structure reduces the stress concentration at an area where the impingement rib meets the platform.

An acrylic resin composition comprising the following acrylic resins (1) and (2): acrylic resin (1): an acrylic resin containing a structural unit derived from a monomer (a) (structural unit (a)), a structural unit derived from a monomer (b) (structural unit (b)) and a structural unit derived from a monomer (c) (structural unit (c)) and containing the structural unit (c) in an amount of 0.05 to 5 parts by weight based on 100 parts by weight of the acrylic resin (1); acrylic resin (2): a straight chain acrylic resin containing the structural unit (a) as the main component;

(a): a (meth)acrylate of the formula (A)

(wherein, R₁ represents a hydrogen atom or methyl group, R₂ represents an alkyl group having 1 to 14 carbon atoms or an aralkyl group having 1 to 14 carbon atoms, and a hydrogen atom in the alkyl group R₂ or a hydrogen atom in the aralkyl group R₂ may be substituted with an alkoxy group having 1 to 10 carbon atoms.),

(b): a monomer containing an olefinic double bond in the molecule and at least one 5- or more-membered heterocyclic group in the molecule, (c): a monomer containing at least two olefinic double bonds in the molecule.

This invention discloses a ternary compound material underlay anti-wearing tube and its process method, which comprises outer steel tube and anti-wearing underlay, wherein, the anti-wearing underlay is composed of metal wire net, ceramics bar and compound materials and the ceramics is imbedded in the metal wire net holes into one part by compound materials. The processed compound materials underlay anti-wearing tube is one of straight tube, bent tube or three-way tube.

The invention relates to an aircraft wing part and especially to an aircraft wing box using a grid structure and a design method thereof. The aircraft wing box comprises grid ribs and skin panels; the skin panels wrap the outer sides of the grid ribs so as to form the aircraft wing box; and the aircraft wing box is characterized in that the grid ribs and a plurality of reinforcing ribs mutually intersect and form grid configuration, the grid ribs and the skin panels are both made of a plurality of layers of fiber reinforced composite laminates, the skin panels are fixed at the outer sides of the grid ribs and the grid ribs are made of eight layers of fiber reinforced composites laid at different angles. According to the invention, the grid ribs and the skin panels in a shape of an equilateral triangle are used, and compared to traditional wing boxes, the aircraft wing box provided in the invention has the following advantages: more superior stress distribution under the action of external load can be obtained, higher specific strength, specific rigidity and structural efficiency are obtained, the phenomenon of local stress concentration is reduced, weight of the structure is decreased, dangerous point stress which easily causes a composite material to lose efficacy is reduced, and bearing capacity and the fatigue life of the structure are improved.

The invention belongs to the technical field of aluminum production, wherein the key technology aims at developing a connection method of cathode carbon blocks and cathode steel bars of aluminum electrolytic cells by means of multi-grooves inserting and a construction thereof. The bottoms of the cathode carbon blocks (piece 1) are provided with a plurality of grooves; the cathode steel bars (piece2) consist of base plates and a plurality of rib plates welded thereon; the grooves of the cathode carbon blocks are correspondingly inserted with the rib plates of the cathode steel bars to completethe assembly of cathode carbon blocks. Compared with the existing cathode carbon blocks, the invention improves the utilization rate of the cathode carbon blocks, reduces the invalid usage amount ofthe cathode carbon blocks, reduces the mechanical machining quantity for forming steel bar grooves on the cathode carbon blocks, reduces the waste residue quantity of the cathode carbon blocks when overhauling the electrolytic cells, reduces the horizontal current in the cathode carbon blocks, removes the existing asphalt damage caused by carbon element paste when assembling the cathode carbon blocks and roasting the electrolytic cells, increases the iron carbon contact area between the cathode carbon blocks and the cathode steel bars, and prolongs the service life of the electrolytic cells.

The invention provides a reactor with an inner supporting structure. The reactor comprises a barrel, material entering and exiting openings arranged on the barrel and the inner supporting structure arranged on the inner wall of the barrel, wherein the inner supporting structure comprises a supporting flange and a supporting rack and the flange surface of the supporting fits the supporting rack and is used for supporting the supporting rack. According to the invention, supporting is realized in the manner that the supporting flange fits the supporting rack through the flange surface of the supporting flange; compared with direct welding of a supporting plate and the inner wall of a barrel of a traditional supporting structure, such a manner has the advantages that strength difference between the supporting flange and the barrel is reduced, local stress concentration between the supporting flange and the inner wall of the reactor is lowered and the supporting flange can bear internal pressure, high temperature and gravitational load at one time, is easy to weld and has low cost; and through usage of the improved inner supporting structure, the reactor can resist corrosion and fatigue and does not crack in operation of the reactor, and has longer service life.

A spring type one-way clutch includes an outer ring rotatable about a rotary shaft and having an inner tubular portion, and a clutch spring mounted in the outer ring. The clutch spring includes a large-diameter coil spring portion, a transition portion connected to the winding end of the large-diameter coil spring portion, and a small-diameter coil spring portion connected to the radially inner end of the transition portion and wound in the opposite direction from the large-diameter coil spring portion. When the outer ring is rotated in the direction opposite the winding direction of the large-diameter coil spring portion, the large and small-diameter coil spring portions are radially compressed and pressed against the inner tubular portion and the rotary shaft, allowing the rotary shaft to rotate together with the outer ring. The transition portion spirals radially inwardly in the winding direction of the large-diameter coil spring portion.

The invention discloses an aluminum-based porous composite material as well as a preparation method and application thereof, and relates to the technical field of gradient composite materials. The preparation method comprises the following steps that a plurality of groups of composite raw materials are laid in a mold layer by layer, and cold pressing forming is carried out to obtain a prefabricated blank; hot pressed sintering is carried out on the prefabricated blank; and each group of composite raw materials comprises aluminum alloy powder and hollow microspheres, at least one parameter index of two adjacent layers of composite raw materials is different, and the parameter indexes comprise the volume fraction of the hollow microspheres, the grain size distribution of the aluminum alloy powder, the grain size distribution of the hollow microspheres, the components of aluminum alloy powder and the components of the hollow microspheres. The preparation method of the composite material is extremely high in designability, and the prepared composite material can form a functional gradient, so that excellent buffering and energy absorbing performance is obtained.

The invention discloses an aluminum-based porous composite material as well as a preparation method and application thereof, and relates to the technical field of composite materials. The preparation method of the aluminum-based porous composite material comprises the steps that multiple sets of composite blank raw materials are laid in a mold layer by layer and subjected to cold press molding, and a prefabricated blank is obtained; pressure infiltration is performed on the prefabricated blank by adopting an aluminum melt; the multiple sets of composite blank raw materials comprise aluminum material powder and hollow microspheres; and the proportions of the aluminum material powder and the hollow microspheres in every two adjacent sets of composite blank raw materials are different. The composite material with gradient distribution or periodic distribution of the hollow microspheres can be prepared through the preparation method, interlayer interface bonding is good, continuous transmission of impact loads is facilitated, and the material has more excellent buffering and energy absorbing performance.

The invention discloses a spatial three-branch beam string structure footbridge which comprises a first main beam, a second main beam and a third main beam, wherein one ends of the three main beams are converged on a convergence node, and the other ends of the three main beams are supported on a bridge abutment through fixed supports; a first dragline is arranged between the middle part of the first main beam and the middle part of the second main beam, a second dragline is arranged between the middle part of the second main beam and the middle part of the third main beam, and a third dragline is arranged between the middle part of the third main beam and the middle part of the first main beam; and three anchorage plates are arranged on the side wall of the convergence node, a first connecting rod is arranged between the first anchorage plate and the first dragline, a second connecting rod is arranged between the second anchorage plate and the second dragline, and a third connecting rod is arranged between the third anchorage plate and the third dragline. According to the spatial three-branch beam string structure footbridge disclosed by the invention, the horizontal displacement of the structure under the action of vertical load can be limited, the integral rigidity of the three-branch beam string structure bridge can be increased, the local stress concentration degree of the convergence node of the three main beams can be reduced, and the vibration comfort can be improved when pedestrians cross the bridge.

The invention discloses a preparation method of polyethylene glycol repaired graphene reinforced aluminum-based composite material, and relates to the preparation method of graphene reinforced aluminum-based composite material. The preparation method aims to solve a problem that grinding aid is residual in an aluminum alloy matrix, and realize self-repairing of the graphene. The preparation methodcomprises the step 1 of weighing the graphene, the polyethylene glycol and aluminum metal powder; the step 2 of putting the material obtained in the step 1 into a ball milling tank for ball milling;the step 3 of cold pressing; and the step 4 of preparing the composite material after the cold pressing. The grinding aid, polyethylene glycol is subjected to thermal decomposition to generate activeC atoms, and the C atoms can adsorb on the pits of the graphene, so that integrity of the graphene structure is greatly improved, good interface connection is formed, and overall performance of the material is greatly improved; the polyethylene glycol is beneficial to flake formation of the aluminum metal powder, so that a problem of high dispersion difficulty of the single-layer or few-layer graphene in the aluminum-based composite material is solved, and cold welding between the aluminum metal powders is reduced; polyethylene glycol is easy to remove, and the prepared few-layer graphene reinforced aluminum-based composite material is excellent in comprehensive performance. The method is suitable for preparing the graphene reinforced aluminum-based composite material.

The invention discloses a cutting device for a digging robot. The device comprises a mechanical arm and a cutting machine which is driven by the mechanical arm to move in the space; the mechanical armcomprises a machine base, an inner arm which is rotatably connected to the machine base at the single degree of freedom in the vertical direction, an outer arm which is rotatably connected to the inner arm at the single degree of freedom in the vertical direction, a first driving device for driving the outer arm to rotate relative to the inner arm and a second driving device for driving the innerarm to rotate relative to the machine base. Therefore, the mechanical arm with high length and weight can be adopted for the cutting device for the digging robot, the bending moment generated under the gravity of the mechanical arm is prevented from damaging the driving devices (usually gear motors), and accordingly the operation range of the cutting device for the digging robot is greatly enlarged.

The invention discloses a circular tooth knife for a plastic pulverizer and a grinding tool and a processing technology thereof, and belongs to the technical field of mechanical cutters. The circular tooth knife comprises a cylindrical knife body, n knife teeth are uniformly distributed in the length direction of the periphery of the knife body, n is larger than or equal to 30 and smaller than or equal to 50, a tooth groove is formed between every two adjacent knife teeth, and arc faces are arranged at the edges in the length directions of the groove bottoms of the tooth grooves. The grinding tool comprises a mounting unit, a positioning unit and a grinding unit, the mounting unit is used for supporting the knife body to be processed, the positioning unit is used for limiting rotation of the knife body on the mounting unit, and the grinding unit is used for polishing cutting edge faces of the knife teeth; and the mounting unit is located between the positioning unit and the grinding unit. The processing technology of a round blade is that after linear cutting is carried out, the grinding tool is used for grinding and machining the cutting edge faces. By means of the circular tooth knife, the sharpness of the circular tooth knife can be ensured, the service life can be prolonged, and the cutting edge faces of the knife can be conveniently and accurately ground.

The invention discloses stalk fiber toughening mortar. The stalk fiber toughening mortar is prepared from the following ingredients in parts by weight: 20 to 40 parts of ordinary portland cement, 50 to 70 parts of perlite, 15 to 35 parts of iron tailings, 15 to 30 parts of waste porcelain powder, 15 to 20 parts of slag powder, 8 to 20 parts of straw fiber, 1 to 1.5 parts of starch ether, 0.5 to 2parts of hydroxy propyl cellulose, 3 to 8 parts of polyvinyl alcohol, 1 to 6 parts of styrene-acrylic emulsion and 2 to 4 parts of methyl cellulose ether. The method comprises the following steps of uniformly mixing the ordinary portland cement, the perlite, the iron tailings, the waste porcelain powder and the starch ether; then, adding the stalk fiber, the hydroxy propyl cellulose, the polyvinylalcohol, the styrene-acrylic emulsion and the methyl cellulose ether; finally adding water; performing mixing to obtain a finished product. The stalk fiber toughening mortar solves the problems of low tensile intensity, easy cracking and the like of the existing mortar due to poor toughness.