77results about How to "Reduce structural mass" patented technology

The invention discloses a hybrid welding method and hybrid welding equipment for laser electromagnetic pulse. The method can be used for laser seam welding and laser spot welding technology, a pulsed high magnetic field is applied to a welding region during the process of laser welding on a workpiece with the effect of laser beams so as to mutually react with an induced plasma, a welding pool and a stress strain field through welding and complete welding task. The equipment comprises a laser device, an electromagnetic pulse generator, a numerical control system, an optical transmission system and a laser electromagnetic pulse combined machining head. The combined machining head is used for integrating the laser beams with the pulsed high magnetic field and adjusting the distance between an electromagnetic conversion device and the workpiece; the combined machining head is arranged on a machine tool. The structural deformation can be reduced, the welding quality and machining efficiency are improved, and insurmountable technical problems when a metallic material structure is manufactured through existing single welding technology are solved.

The invention discloses a multilayer grating bearing cylinder and a preparation method thereof. The multilayer grating bearing cylinder is formed by nesting at least two single-layer grating cylinders, and the densities of the meshes of the adjacent single-layer grating cylinders are different. The preparation method for the multilayer grating bearing cylinder made from a composite material comprises the following steps: producing a wood pattern for casting a soft mode, producing a silicon rubber soft mode, assembling a mould, winding the soft mode in an assistance manner, carrying out vacuum bag moulding, demoulding and carrying out after-treatment, and integrally moulding the multilayer grating bearing cylinder; or preparing the single-layer grating cylinders according to the steps, and then assembling the single-layer grating cylinders into the multilayer grating bearing cylinder. The preparation method for the multilayer grating bearing cylinder made from metal or engineering plastic comprises the following steps: preparing a casting mould for the disassembly components of the single-layer grating cylinders, melting and casting, welding, and then assembling the single-layer grating cylinders into the multilayer grating bearing cylinder; or moulding in one step by a 3D printing technology. The multilayer grating bearing cylinder has the characteristics of good structural stability, light mass, high mechanical properties, difficulty of structural overall buckling instability, simple and practicable preparation method, and low cost.

The invention relates to a tail rotor pitch structure of an unmanned helicopter, which is composed of a bearing pedestal, a steering engine, a variable-pitch slide block, an universal drive shaft head A, a variable-pitch pull bar, an universal drive shaft head B, a pitman arm, a belt wheel, a threaded hole, a transmission shaft, a fixing threaded hole, a steering engine auricle and a tail rotor rocking arm. The bearing pedestal and a tail boom are connected through a screw, the transmission shaft and the belt wheel are fixedly connected, the power input of the transmission shaft can be realized by belt driving formed by the belt and the belt wheel; the steering engine auricle and the bearing pedestal are connected by a screw, the steering engine and the pitman arm are connected through a pitman arm screw, the pitman arm and the end part of the variable-pitch pull bar through the universal drive shaft head B; the variable-pitch slide block and a tail rotor transmission shaft are connected through the bearing, one end of the variable-pitch pull bar and the variable-pitch slide block are connected by the universal drive shaft head A, so that connection of the steering engine and the variable-pitch slide block is realized; and the variable-pitch slide block and the tail rotor rocking arm employs circumferential rotatable connection. According to the invention, a structure design of the tail rotor with high accident rate can be optimized, structural quality is mitigated, connection reliability is enhanced, and the tail rotor pitch structure is an optimization scheme of tail rotor transmission.

The invention relates to a trimix pressurization system applied to a liquid rocket. The trimix pressurization system comprises a helium and hydrogen bottle (1), an oxygen bottle (2), a flow control unit and a catalytic bed (5), wherein mixed helium and hydrogen are stored in the helium and hydrogen bottle (1) in advance; oxygen is stored in the oxygen bottle (2); flow of gas output in the two bottles is controlled through the flow control unit; a mixed gas of output helium, hydrogen and oxygen is subjected to catalytic reaction through the catalytic bed (5); oxygen and hydrogen react to generate water vapor and release hat; and helium, water vapor and oxygen remaining after reaction are heated and enter a storage tank to pressurize the storage tank.

The invention discloses a connecting and sealing device comprising a shell and a spraying pipe connected with the shell. An assembling groove is formed in the inner wall of the shell; the spraying pipe is provided with an assembling step matched with the assembling groove; a clamping groove is further formed in the shell and is internally provided with a snap ring matched with the clamping groove; and part of the snap ring is installed in the clamping groove, and part of the snap ring is tightly clamped to the spraying pipe. The device is complete in function and convenient to operate and has high universality. At present, the device has been applied to many products, many experiments are successfully completed, a good effect is achieved, the assembling problem of a spraying pipe of a small-diameter solid rocket engine can be solved, and the purposes of reducing the structural mass and improving the assembling efficiency are achieved.

The invention relates to the field of structural analysis of friction stir welding robots, in particular to a topological optimization design method for a stand column structure of a friction stir welding robot, which comprises the following steps of: 1, dynamically optimizing the stand column structure; 2, optimizing the load and boundary conditions of the stand column structure; 3, realizing topological optimization analysis of the stand column structures: firstly, carrying out three-dimensional modeling, carrying out mesh generation on a stand column model after modeling, then applying loadvalues under different working conditions to the model, carrying out topological optimization respectively, carrying out weighted optimization analysis on the stand column structures after topological optimization, and obtaining a final optimization result; and 4, reasonably configuring the stand column structure according to the obtained topological optimization analysis result of the stand column structure. According to the method, optimization design is carried out on the stand column structure firstly, then a new round of topological optimization correction design is carried out on the stand column structure again according to the optimized structure, and therefore the light-weight stand column structure with the excellent comprehensive dynamic performance is obtained.

The invention relates to a rapid collaborative optimization method for a hybrid fiber composite material plate shell structure, which belongs to the technical field of composite material structure optimization design, and comprises the following steps of: 1) establishing an alternative material library; 2) establishing a three-dimensional finite element numerical model and performing geometric partitioning; 3) establishing a reduced-order numerical analysis model by using a model reduced-order method; and 4) establishing an optimized column, and carrying out discrete material optimization design. A continuous interpolation function is adopted to represent a discrete material in a material library, numerical calculation is carried out by adopting a reduced-order model to obtain a target anda constraint response according to geometric partitions, an optimization target and a constraint distribution design variable of a model, discrete material optimization design is carried out, multi-variable collaborative optimization is realized, and an optimal design configuration is obtained. Integrated design of the hybrid fiber composite material structure can be achieved, collaborative optimization design of multi-level variables such as the structure topology, the fiber content, the fiber angle and the laying sequence is achieved, the structural function requirement is met, meanwhile, the structural mass is reduced, and the material cost is reduced.

The invention discloses a wave-absorbing composite material and a preparation method thereof. The wave-absorbing composite material comprises a wave-transparent layer, a reflecting layer and a wave-absorbing layer arranged between the wave-transparent layer and the reflecting layer, wherein the wave-absorbing layer comprises multiple layers of wave-absorbing hollow fabric composite materials which are sequentially stacked, and each layer of wave-absorbing hollow fabric composite material comprises a hollow fabric and a resin which is filled on the fiber surface of the hollow fabric and is dispersed with a wave-absorbing agent. According to the invention, a wave-absorbing agent is dissolved in a resin, and the wave-absorbing resin is added to the fibers of a hollow fabric, so that the wave-absorbing agent of the prepared multi-layer wave-absorbing hollow fabric composite material is uniformly dispersed, the wave-absorbing composite material is excellent in overall performance, does not have interfacial properties, and has excellent properties of light weight, high strength, layering resistance and impact resistance, and different wave-absorbing paving layer structures can be designed according to the requirements of the electrical property and the mechanical property so as to achieve the compatibility of the electrical property and the mechanical property and meet the feasibility of a forming process.

The invention provides an L-shaped composite material laminboard connecting structure with a flexible metal connector. The structure comprises foamed laminated composite material plates and metal connecting parts, wherein pre-buried metal plate parts of the metal connecting parts are embedded between laminated foams and composite material plates; composite material laminboards and the metal connecting parts are cured together by using an integral molding technique. Due to adoption of adjustable flexible connectors, the assembling stress is effectively reduced, and flexible assembling is achieved; the pre-buried metal plate parts are designed as a forked tail structure, so that the concentrated stress at the connecting parts of the metal plates and the composite material plates is effectively reduced; the connecting parts are of circular arc-shaped design, so that the bending strength is improved; due to a co-curing technique, composite material openings and the like are avoided, and the integrity of the composite material plates is ensured; a relatively large space is reserved in the metal connecting parts, so that convenience can be brought to pipeline laying and later maintenance. The structure is applicable to mechanical connection of composites material laminboards and other structures of large-size structures.

The invention provides a turbine engine. The turbine engine comprises a first housing, a second housing, a third housing, a central body, an oil passage assembly, an igniter, a compressor, a turbo machine and a spindle. The first housing has an air inlet. The third housing is fixedly connected to the first housing and the second housing and communicates with the first housing and the second housing. The central body is arranged in the third housing. The outer wall surface of the central body and the inner wall surface of the third housing form a rotary detonation combustion chamber. The oil passage assembly communicates to the rotary detonation combustion chamber in a controllable manner. The igniter is used for igniting combustion gas which is formed by fuel and air entering the rotary detonation combustion chamber such that combustion gas rotates and combusts in a detonation manner. The compressor is used for compressing air entering the first housing through an air inlet. The turbo machine performs rotary motion under the drive of gas in the second housing. The spindle is used for connecting with the compressor and the turbo machine such that the turbo machine drives the compressor to perform motion. The turbine engine has following beneficial effects: the turbine engine is compact in structure and high in combustion efficiency; oil consumption rate of the engine is reduced; and the thrust-weight ratio and the overall performance of the engine are improved.

The invention discloses a composite-material core-level cover plate for a rocket, and a preparation method thereof. The cover plate comprises nine detachable units, wherein each detachable unit is a composite-material interlayer structure containing an inner framework; and one is a central quadrilateral unit and the other eight detachable units are divided into four groups, the two detachable units in each group are connected together through a hinge, the four sides of the central quadrilateral unit are lapped and fixed to one turned edge of the four groups of detachable units separately, theother sides of the four groups of detachable units are placed on a launching platform installation frame and fixed, and the whole outer edge outline is determined by an installation connector space where the cover plate is located. The invention puts forward for the first time that a light-weight foam interlayer structure containing the inner framework is applied to the core-level cover plate forthe rocket. The composite-material core-level cover plate has the advantages of being convenient to transport, simple to install, rapid to detach, and the like; and the disclosed preparation method has the advantages of ensuring the good forming quality of products, realizing integrated forming, and achieving low cost.

The invention relates to a self-propelled totally-enclosed environmental-friendly energy saving sweeping vehicle, comprising a vehicle head and a vehicle frame which are combined into a whole, as well as a brush roller and a dustbin which are arranged on the vehicle frame, wherein two sides of the vehicle head and the vehicle frame are respectively provided with a moving wheel; the brush roller driven by the moving wheels of the vehicle head is transversely arranged on the vehicle frame; a large number of floor sweeping brushes are arranged on the brush roller; the dustbin is arranged on the rear upper part of the frame through a rotating shaft and a hydraulic self-unloading mechanism; a garbage conveying chain is arranged between an inlet of the dustbin and the front of the sweeping brush roller; two ends of the garbage conveying chain are respectively arranged on the vehicle frame through sprocket wheels. The invention has the advantages that: the sweeper is thorough in sweeping, high in efficiency, free from raising dust, light in load, low in energy consumption, convenient to use, totally enclosed in the whole process of floor sweeping operation, capable of sweeping and collecting a variety of lightweight and hard garbage effectively and good in garbage collecting effect, which solves the problem that the prior sweeper is not thorough to sweep garbage and does not collect garbage so as to cause secondary pollution and raising dust pollution.

The invention relates to a traction-type totally-enclosed self-unloading environmental-friendly energy saving sweeper, comprising a traction frame, moving wheel, a brush roller and a dustbin which are arranged on a frame, wherein the traction frame is arranged at the front end of the frame; the moving wheel are power wheels; the sweeper comprises two moving wheels positioned on two sides of the frame; the brush roller driven by the moving wheel is transversely arranged on the frame; a large number of floor sweeping brushes are arranged on the brush roller; the dustbin is arranged on the rear upper part of the frame through a rotating shaft and a hydraulic self-unloading mechanism; a garbage conveying chain is arranged between an inlet of the dustbin and the front of the brush roller. The invention has the advantages that: the sweeper is thorough in sweeping, high in efficiency, little in raising dust, light in load, convenient to use, totally enclosed in the whole process of floor sweeping operation, capable of sweeping and collecting a variety of lightweight and hard garbage effectively and good in garbage collecting effect, which solves the problem that the prior sweeper is not thorough to sweep garbage and does not collect garbage so as to cause secondary pollution and raising dust pollution.

The invention discloses a material feeding mechanism for a 3D printer. The material feeding mechanism comprises a stepping motor, wherein the stepping motor is connected with a motor bracket, the upper part of the motor bracket is connected with a fixed pressure plate, the motor bracket is connected with an upper connecting plate of the printer, a U-shaped groove is formed in the motor bracket, bracket screw holes are formed in the two sides of the mouth of the groove respectively, bosses are formed in the two sides of a horizontal end surface respectively, a motor connecting hole is formed in each boss, a wire feeding driving wheel is arranged on an output shaft of the stepping motor, a wire inlet and a wire outlet which are vertical to the axial line of the U-shaped groove are formed in each boss, a rectangular groove hole is formed in the middle of the fixed pressure plate, wire feeding wheel connecting holes are formed in the two side walls of the rectangular groove hole respectively and provided with wire feeding wheel fixed shafts respectively, and a wire feeding wheel is arranged on each wire feeding wheel fixed shaft and in the rectangular groove hole and is matched with the wire feeding driving wheel to finish feeding of a printing wire. The material feeding mechanism has a compact structure, is light in quality, good in rigidity, convenient to assemble and disassemble and less prone to deformation and is capable of ensuring reliable feeding of the printing wire and the quality of a printed product.