75results about How to "Optimize the power transmission path" patented technology

The invention discloses a circular steel tube concrete column and beam node connecting structure, which is characterized in that: the connecting structure comprises a node fastener, a bolt, a circular steel tube concrete column and a beam; the node fastener is composed of two sections of fastening rings and a joint, and the joint is in sleeve type and horizontally H-shaped type, the circular steel tube concrete column penetrates in the fastening rings and is fastened by the bolt, and the beam is connected by the joint on the fastener; the field installation is convenient without welding and the construction is rapid; the fastener is composed of two sections and is connected by the bolt after being fixed, and the circular steel tube concrete column is fixed by tightening force of the fastener; the circular steel tube concrete column is inserted in the sleeve type joint and is fixedly connected with the sleeve type joint by the bolt, and a concrete beam steel bar and a steel girder are welded with the horizontally H-shaped type joint; besides welding of the concrete beam steel bar and the horizontally H-shaped type joint, in the whole process, welding and complex distributed steel do not need, the construction is simple and rapid.

The invention relates to a construction method for double-sided enhancement or reinforcement of the engineering structures, belonging to the technical field of enhancing or reinforcing the engineering structure through high-strength fibrous composites, which is characterized in that: holes are drilled on a surface of the enhanced or reinforced civil engineering structure, and longer screws are embedded in the holes to fix two pairs of wave-shaped gear-grip anchors at the same time, so that the high-strength fibrous composite sheets can be drawn and fixed by the anchors at the two sides of the engineering structure. The construction method for double-sided enhancement or reinforcement of the engineering structures has the advantages of definite and even stressing, simple path of force transfer, convenient construction and operation, high efficiency, improving the loading capacity of the civil engineering structures and extending the service life of the civil engineering structures, and is widely used in large-scale building structures of the civil engineering, especially in the construction, reconstruction and maintenance of the large-scale thin wall structures (like T-shaped beams, etc.).

The invention relates to the field of aerospace structure main load-bearing member design, and provides an opening reinforcement method of a shaft pressing reinforced cylindrical shell. The opening reinforcement method of the shaft pressing reinforced cylindrical shell comprises the following steps: step 100, dividing the shaft pressing reinforced cylindrical shell with an opening into a distal opening area and a proximal opening area; step 200, establishing an equivalent stiffness model in the distal opening area, establishing a fine geometric model in the proximal opening area, and obtaining a hybrid analysis model of the shaft pressing reinforced cylindrical shell; step 300, peforming opening reinforcement and optimization on the shaft pressing rinforced cylindrical shell, and verifying an optimal result. According to the opening reinforcement method of the shaft pressing rinforced cylindrical shell, the opening reinforcing efficiency of the shaft pressing rinforced cylindrical shell can be improved, and the computing cost is reduced.

A drive unit for a tracked vehicle includes a track support beam, at least one drive wheel, a set of support wheels and an endless track, the drive wheel being arranged to drive the endless track running over the drive wheel and the set of support wheels. The drive wheel and the support wheels are rotatably attached in the track support beam. The drive unit further includes and electric motor attached to the drive wheel and integrated in the track support beam, and a support beam integrated lubrication system having a pump unit arranged for pressurized supply of lubricant to parts of the drive unit in need of lubrication.

The invention provides a sealing assembly with a comb-tooth-shaped limiting device for a core-taking soft bag. The sealing assembly comprises a core-taking mechanism, a buckling mechanism and the comb-tooth-shaped limiting device. The core-taking mechanism comprises a lifting rope, the soft bag, a core-taking pipe and an outer protective pipe. The inner wall of the part, matched with the tail endof the core-taking pipe, of the comb-tooth-shaped limiting device is provided with a core-taking pipe centering ring face, and a plurality of protrusions are evenly distributed at the upper end of thecore-taking pipe centering ring face in the circumferential direction. A gap is formed between every two adjacent protrusions, and a strip-shaped line containing groove is connected with the lower portion of each gap. Annular ball containing grooves are formed in the positions, corresponding to the radial outer sides of the protrusions, of the inner wall of the comb-tooth-shaped limiting device,the protrusions correspond to the annular ball containing grooves in position, and the buckling mechanism comprises seal openings, fisherman knots and limiting balls. The sealing effect of while-drilling sealing and multi-time sealing in the drilling process is achieved, the sampling sealing reliability is improved, and by decreasing the random eccentric magnitude of the core-taking pipe, reducingcore lifting force in the drilling process and the sealing process and reducing fluctuation of the core lifting force, smooth implementation of lunar exploration sampling engineering is guaranteed.

The invention discloses a topology optimization-based cobweb-like interlayer rib plate composite structure design method, which comprises the following steps of: 1, performing a static analysis on an original structural component to obtain a deformation cloud chart; 2, performing a topological optimization design on the structural component to obtain a topological optimization unit pseudo-density diagram; 3, finding the position of a largest deformation zone from the deformation cloud chart of the structural component; 4, arranging annular regular parallels and regular meridian lines of the structural component; 5, determining the arrangement density of the regular meridian lines; 6, arranging irregular meridian lines on some parts of the component; 7, combining the topology optimization to obtain a hollow component structure; 8, making a thin layer plate on the upper layer of the cobweb-like interlayer rib plate to fully envelope the cobweb-like rib plate, so that the middle interlayer becomes a composite structure of the cobweb-like rib plate; and 9, repeatedly improving the original component according to the steps. The invention has scientific concept and a novel structure, can meet the requirement of aerospace on light weight design, and has good practical value and wide application prospect in the engineering and technology field.

The invention relates to a node system for a laminated wood space structure, which belongs to the technical field of a building structural member. The node system can be used for rapidly assembling the laminated wood space structure. The node system comprises a plurality of laminated wood components; and the node system also comprises a node steel hub, a plurality f groups of bolt plates and a plurality of bolts; the outer side surface of the node steel hub is detachably connected with a plurality of groups of bolt plates, each group of bolt plates comprises four bolt plates, and a laminated wood component is detachably arranged between every two bolt plates of each group of bolt plates. The node system is simple and convenient in installation process, the application period of a scaffold is short, and the wooden structure can be rapidly spliced on site.

The invention provides a vehicle towing hook traction device. The device comprises a towing hook body, a towing hook sleeve, a rear axle beam, a towing hook reinforcing plate, a crash box, a sleeve installation support, a front installation plate, a rear outer plate and a rear installation plate, the rear portion of the towing hook body is in threaded connection inside the towing hook sleeve, the front portion of the towing hook sleeve is fixedly connected to the towing hook reinforcing plate, the towing hook reinforcing plate is fixedly connected to the rear axle beam, the rear portion of the towing hook sleeve is fixedly connected to the sleeve installation support, the sleeve installation support is fixedly arranged inside the crash box, the rear end of the crash box is fixedly connected to the front installation plate, the front installation plate, the rear outer plate and the rear installation plate are fixedly connected together, and the rear installation plate is fixedly connected to a longitudinal beam of the vehicle. The vehicle towing hook traction device has the advantages that the connection is strong and effective, the carrying capacity is great, the manufacturing cost is low, the connection is convenient, the installation and maintenance are convenient, the great traction strength is guaranteed, the interference to peripheral equipment does not occur, and great practicability and market application value are achieved.

The invention relates to a wide-purlin bridge floor system structure with a horizontal K support, comprising a main purlin node, a main purlin chord member, a steel bridge panel, a longitudinal rib and main cross beams, wherein the longitudinal rib is arranged on the lower bottom surface of the steel bridge panel; the main cross beams are arranged below the steel bridge panel; two ends of each main cross beam are connected with the main purlin node; a plurality of secondary cross beams are arranged between the two main cross beams; two sides of the steel bridge panel are provided with side longitudinal beams; two ends of the side longitudinal beams are connected with the main cross beams; two ends of the secondary cross beam are connected with the side longitudinal beams; and the main purlin node is connected with the side longitudinal beams on two sides of the end part of the main cross beams by a horizontal K support. Longitudinal loads, such as bridge floor braking force, main purlin lower-chord axial force and the like borne by the bridge floor and the like, are transferred to the main purlin node by a longitudinal force transferring system comprising the bridge panel, the side longitudinal beams and the horizontal K support. The wide-purlin bridge floor system structure has excellent power performance. The traditional brake support is replaced, steel materials are saved, and the wide-purlin bridge floor system structure adapts to the requirement of high speed car running and can be used for the structural design of the bridge floor of longspan and super-longspan steel trussed-beam bridges.

The invention discloses a four-vertical-fin load loading method which comprises the following steps: 1) installing a vertical fin frame between inner vertical fins, connecting a single lug at the upper end of the vertical fin frame to a loading cross beam, and enabling the distance between the lower end of the vertical fin frame and a rear fuselage of an aircraft to be not less than 300mm; (2) theupper end of the vertical fin frame being connected with a loading cross beam through an upper end pull plate, and the lower end of the vertical fin frame being connected with a lateral loading standcolumn through a lower end pull plate; 3) installing an actuating cylinder fixing seat at a position corresponding to the vertical fin frame; 4) installing an actuating cylinder base at a position corresponding to the lateral loading cross beam of the vertical fins; 5) connecting the actuating cylinder with a loading cross beam by using a manual hoist, adjusting the actuating loading to meet therequirement by adjusting the manual hoist, and connecting the actuating cylinder with a vertical fin end lever; and (6) repeating the steps (2) to (5) to install the vertical fin loading equipment onthe other side. The four-vertical-fin load loading method can realize bidirectional tension and compression loading of vertical fin loads, and can avoid the spatial interference problem between the loading equipment and between the loading equipment and a test piece.

The invention belongs to the technical field of experiment tools of main bearing components of aerospace structures and relates to a flexible tool structure with changeable stringer positions. The structure comprises an upper end frame, a lower end frame and horizontal and vertical stringers with changeable positions, wherein the vertical stringers with changeable positions are used for simulating experiment load distribution condition. By changing the distribution angles of the vertical stringers, the designability of the rigidity distribution of the flexible tool can be achieved; the rigidity distribution of the flexible tool is consistent with the rigidity distribution of the real boundary; the force transmission path of the experiment tool can be significantly improved; the accuracy of the check experiment of a cylindrical shell structure is improved. In addition, the flexible tool structure has the advantages of simple structure and low manufacturing cost.

The invention discloses a homing type topological optimization method for mortise and tenon joint structure design. The homing type topological optimization method specifically comprises the followingsteps: step 1, establishing a finite element model of a to-be-optimized structure; step 2, selecting an area where a mortise (1) and a tenon (2) are located as a design domain; step 3, selecting a basic unit, and determining basic structural forms of the tenon (2) and the mortise (1); step 4, running primary finite element analysis; step 5, filtering and leveling the unit strain energy calculatedin the step 4; step 6, enabling the basic unit and the amplification unit to carry out amplification; step 7, calculating the neighborhood state of each unit in the design domain; step 8, setting local control parameters and constructing a local control rule; step 9, performing convergence judgment; and step 10, analyzing and evaluating an optimization result. According to the method, by changingthe basic shape form of the mutually matched and connected parts in the mortise and tenon joint structure, optimization can be conducted within a large range, and then the force transmission path ofthe mortise and tenon joint structure is optimized.

The invention provides an overall structure of an assembly recovery rocket based on a general core level. The overall structure comprises the following components of two first-stage liquid oxygen kerosene engines, a first-stage empennage, a first-stage tail section, a first-stage rear transition section, a first-stage kerosene tank, a first-stage inter-tank section, a first-stage liquid oxygen tank, a grid rudder and a second-stage inter-tank section. Two second-stage liquid oxygen kerosene engines, a second-stage kerosene tank, a second-stage tank interval section, a second-stage liquid oxygen tank, an instrument disc, a supporting cabin, an adapter and a belting connection unlocking device; each universal core-level booster comprises a nose cone, a grid rudder, a reaction thrust system, a liquid oxygen tank, an inter-tank section, a coal oil tank, a rear transition section, two liquid oxygen kerosene engines, a tail section and a landing buffer mechanism; front, middle and rear binding connection devices; a satellite fairing; the reverse thrust rocket is arranged between the first core stage and the booster box; and the forward thrust rocket and the reverse thrust rocket are arranged in the second-stage coal oil tank. According to the invention, general core-level assembly recovery is realized for the first time in China, an efficient and reliable assembly rocket recovery scheme is provided, the safety of a rocket falling area can be improved, and the rocket launching cost is greatly reduced.

The invention discloses an embedding type anchoring device for a pre-stressed anchor cable. The embedding type anchoring device comprises a strengthening structure connected with a soil blocking structure steel bar framework. The strengthening structure is provided with anchor supports. The anchor supports are provided with steel strand holes. According to the device, the anchor cable and soil blocking structures are directly connected. An anchoring method comprises the following specific steps that firstly, the soil blocking structure steel bar framework is manufactured, and the embedding type anchoring device for the pre-stressed anchor cable is fixed to the soil blocking structure steel bar framework; secondly, the soil blocking structure steel bar framework is hung in a preformed soil blocking structural hole, and concrete is poured in the soil blocking structure steel bar framework so as to form the multiple soil blocking structures; thirdly, after the concrete of the soil blocking structures is solidified, a concrete protection layer at the anchor supports is chiseled at the anchor cable elevation position to expose the steel strand holes; and fourthly, the free end of a steel strand of the anchor cable penetrates the steel strand holes, and tensioning and locking are achieved through an anchor. According to the method, construction is convenient, and the falling risk of the anchoring structure is avoided.

The present invention discloses a double-toothed-connection-component inner double-walled pipe combination member and a manufacturing method thereof. The double-toothed-connection-component inner double-walled pipe combination member comprises an outer pipe and an inner pipe, wherein concrete is filled between the outer pipe and the inner pipe, and toothed connection components are formed on the inner wall of the outer pipe and the outer wall of the inner pipe.

The invention relates to an integral space structure for an offshore converter station, and mainly relates to the field of offshore wind power development, in particular to the field of offshore electrical boosting platforms. An upper module in the integral space structure for the offshore converter station provided by the invention forms a three-transverse-truss four-longitudinal-truss space frame system, wherein transverse trusses are used for bearing large-span weight load of a main structure, and longitudinal trusses are used for transmitting loads, form a whole with the transverse trussesand are transmitted to the jacket and the pile foundation; therefore, it is guaranteed that the structure has enough overall rigidity, the natural vibration frequency is larger than 0.6s, the structure is far away from the wave main frequency, and the vibration of the structure under the effect of environment loads is reduced. In the transportation period, temporary binding members are arranged to share stress on main columns of a valve hall transverse frame, the risk that a main frame is unstable when inertia effects such as rolling or pitching or heaving happen to a ship in the marine transportation period is reduced, and the situation that the design size of main column members is too large is avoided.

The invention discloses a corrosion resistant method and a structure of a steel column base with a shoe plate. The method is to drill a set of drainage holes in the bottom of the shoe plate for welding a joist steel wing plate with a baseplate so as to timely drain water or corrosive liquid falling in a closed space of the steel column base to realize the corrosion resistant purpose of the steel column base with the shoe plate. Several drainage holes are drilled in the bottom of the shoe plate surrounding the closed space of the steel column base, are semicircular holes or rectangular holes, and tightly adhere to a bottom hole plane to timely drain the water or corrosive liquid entering the closed space of the steel column base so as to prevent the water or corrosive liquid in the closed space of the steel column base, so that the durability of the steel column base is improved, and the steel column base with the shoe plate can be exposed outside for use. The corrosion resistant method and structure have the characteristics of low cost, simple production, convenience for construction, simple force transfer path, strong bending resistance and shearing resistance and reliable connection with a foundation, effectively solve the problem of easy corrosion of a traditional exposed steel structural column base with the shoe plate, and improve the structural durability.

The invention provides a piece of power splitting tension loading test equipment suitable for CT scan. The equipment comprises the following components: a pulling force platform, a pulling and pressing converting mechanism, a pressure platform, a universal joint, steel poles, a test piece, a constraint platform, a pressure and displacement sensor, and a computer control system. A test piece is clamped between the constraint platform and the pressure platform; the universal joint guarantees realization of parallel pressurization; the pressure platform and the constraint platform are connected into a reaction frame through the steel poles, in order to form a self-balance system; the pulling force platform and the pressure platform are connected by the pulling and pressing converting mechanism, in order to realize conversion from pulling force load into pressure load; the pulling force platform is externally connected to a hydraulic elongator, in order to carry out application of dynamicloading; the load and displacement sensor, and the computer control system can guarantee loading mode and loading rate of the test, and at the same time experiment data is recorded. The equipment hasa small volume and is convenient for movement, and can be placed in a detection scope of a medical X-ray CT machine, in order to realize synchronization of measurement and loading, and effectively solve the problem of synchronous recording of crack initiation in the splitting tension test process.

The invention discloses a horizontal truss system containing a giant arch and a construction method of the horizontal truss system. The horizontal truss system is arranged on the upper portions of a plurality of barrels and comprises a horizontal truss structure, the whole horizontal truss structure is in a rectangular-ambulatory-plane shape, each barrel is of a reinforced concrete structure and comprises a core barrel and a steel framework, the upper end of the core barrel penetrates through the horizontal truss structure, the pair of giant arches is arranged on each edge of the horizontal truss structure and located between the barrels on the two sides, a pair of inclined arches is arranged between the barrels on the two sides of each corner, and the structure forms a stress self-balancing system and has few supporting structures; the construction method of the structure mainly comprises the steps of steel structure installation of the barrel, concrete structure construction, supporting structure building, steel bar truss floor support plate laying, giant arch and horizontal truss structure installation and supporting structure dismantling, a stress self-balancing system is built through an auxiliary supporting structure, the construction process of the structure is simplified, and the construction period and cost are reduced.

The invention relates to a drive unit for a tracked vehicle such as a tracked forwarder. The drive unit comprises a track support beam, at least one drive wheel, a set of support wheels and an endless track, said at least one drive wheel being arranged to drive said endless track running over said at least one drive wheel and said set of support wheels. The drive wheel and the support wheels are rotatably attached in said track support beam. The drive unit further comprises an electric motor attached to said at least one drive wheel and integrated in said track support beam, and a in the track support beam integrated lubrication system comprising a pump unit arranged for pressurized supply of lubricant to parts of the drive unit in need of lubrication.

The invention relates to a frame type curtain wall fabricating structure. The frame type curtain wall fabricating structure comprises an upright post and a cross beam, wherein the front end of the cross beam is fixed to the front end of the upright post through a plurality of stainless steel pan head self-tapping nails, and the rear end of the cross beam is fixed on the rear side of the upright post through fixing pins; an aluminum alloy buckle cover is arranged on the front side of the upright post, a multi-layer hollow toughened glass is arranged on the outer side of the cross beam, and theupright post is connected to the end of the multi-layer hollow toughened glass through a heat-insulation profile; and an opening frame is arranged on the side, close to the multi-layer hollow toughened glass, of the cross beam, the opening frame is connected and fixed to the upright post, an opening fan is arranged in the opening frame, and the opening fan is connected with the multi-layer hollowtoughened glass. According to the frame type curtain wall fabricating structure, the consumption cost of vertical keels and rear embedded parts of a curtain wall is reduced, the site construction progress is accelerated, and the economic benefit is obvious.

The invention discloses a drive system for change of pitch of a helicopter tail rotor and a helicopter. The drive system comprises a tail rotor shaft and a pitch change mechanism, wherein the pitch change mechanism comprises a pitch change disc, a pitch change sleeve and a drive assembly, a drive rod is arranged on the pitch change disc, the drive assembly comprises a steering engine, a pull rod and a pitch change rocker, the steering engine is fixed on a tail rotor support, an output end of the steering engine is located in the tail rotor support, one end of the pull rod extends into the tailrotor support and is hinged with the steering engine rocker, the other end extends out of the tail rotor support and is hinged with one end of the pitch change rocker, and the other end of the pitchchange rocker is hinged with the pitch change sleeve. The steering engine drives the pull rod to move up and down so as to drive the pitch change rocker to move with the pull rod, the pitch change rocker drives the pitch change sleeve to slide axially, so that the pitch change sleeve drives the pitch change disc to slide axially, the pitch change disc drives a tail rotor paddle assembly to rotate,and the pitch of the tail rotor is changed. Meanwhile, by arrangement of the pitch change disc, torque transfer of the tail rotor shaft is realized, and the service life of bearings and other parts is prolonged.

The invention provides a superconducting magnet connecting device and a superconducting electric magnetic levitation vehicle track system, and the superconducting magnet connecting device comprises a cavity which is disposed on a suspension framework; a heat insulation supporting mechanism which is arranged in a superconducting magnet and is used for connecting and fixing the inner Dewar flask of the superconducting magnet; an elastic supporting mechanism which is arranged in the cavity and used for absorbing first resultant force applied by the suspension framework through the cavity and outputting second resultant force buffered by the first resultant force; a force transfer component which is arranged between the superconducting magnet and the suspension framework; and a plurality of force transmission components which are connected with the heat insulation supporting mechanism and the force transfer component, and are used for dispersedly acting the second resultant force on the heat insulation supporting mechanism so as to dispersedly transmit the second resultant force to the inner Dewar of the superconducting magnet. The force transmission path from the superconducting magnet to the suspension framework is simplified, and the problems that the rigidity requirement of the superconducting magnet is high, the running comfort of a vehicle is low, and the superconducting magnet cannot be stably and safely supported when the vehicle runs at a low speed are solved.

An all-electric push satellite platform configuration based on the self-tandem launch method of one arrow and two satellites: including: two sub-satellite platforms with the same structure, and a connection and separation device (61); the connection and separation device (61) is installed in the central load-bearing cylinder ( 121) one end, passing through the -Z board (122) of the sub-satellite platform is connected with the +Z board (111) of another sub-satellite platform. The invention realizes the self-tandem launch of one arrow and two satellites through structural optimization design and connection and separation device. At the same time, the two-chamber configuration, comprehensive layout of load and platform equipment, and innovative layout of batteries and electric thrusters are adopted to realize on-board resource sharing, simplify the test process, reduce satellite weight and power requirements, and further improve satellite load-carrying capacity .

The invention discloses a spliced structure type lifting guide rail. The rail is formed by splicing a plurality of splicing units in a linear end-to-end sequence, wherein each splicing unit comprises a guide rail body and a vertical rod welded to the guide rail body, and end steel plates are welded to the end faces of the two ends of the guide rail body; the two ends of each splicing unit are a head end and a tail end correspondingly, wherein the end of the guide rail body in the head end protrudes out of the end of the vertical rod, and the end of the vertical rod in the tail end protrudes out of the end of the guide rail body; and in the spliced structure of every two adjacent splicing units in the relation of an upper section and a lower section, the vertical rod at the tail end of the upper section of splicing unit is fastened to the guide rail body at the head end of the lower section of splicing unit through a bolt, and the end steel plates of the two guide rail bodies of the upper section of splicing unit and the lower section of splicing unit are fastened in cooperation with bolts after being attached. According to the spliced structure type lifting guide rail, a staggered inclined connection manner is adopted, the force transmission path is greatly improved, the rail splicing contact cross section is enlarged, and the strength and rigidity of the guide rail and a vertical main frame are enhanced.

The invention discloses a prestress assembly type concrete frame supporting structure of a wind turbine generator set, the top end of a supporting structure is provided with a steel tower to be fixed, the top end of the steel tower is provided with the wind turbine generator set, and the supporting structure comprises a bottom-layer supporting unit, a middle-layer supporting unit, a top-layer supporting unit and a plurality of prestressed steel strands. The bottom-layer supporting unit is of a rectangular frame body structure; the middle-layer supporting unit is arranged at the upper end of the bottom-layer supporting unit, and the middle-layer supporting unit is formed by overlapping a plurality of standard structure units; the top-layer supporting unit is arranged at the top end of the middle-layer supporting unit; and the prestressed steel strands penetrate through hole bodies longitudinally formed in the bottom-layer supporting unit, the middle-layer supporting unit and the top-layer supporting unit correspondingly, and longitudinal connection and fixation of the bottom-layer supporting unit, the middle-layer supporting unit and the top-layer supporting unit are completed. By means of the supporting structure, the problem that node bolts and inclined struts in a traditional lattice type tower are unfavorable in stress is effectively solved.

The invention provides a vehicle towing hook traction device. The device comprises a towing hook body, a towing hook sleeve, a rear axle beam, a towing hook reinforcing plate, a crash box, a sleeve installation support, a front installation plate, a rear outer plate and a rear installation plate, the rear portion of the towing hook body is in threaded connection inside the towing hook sleeve, the front portion of the towing hook sleeve is fixedly connected to the towing hook reinforcing plate, the towing hook reinforcing plate is fixedly connected to the rear axle beam, the rear portion of the towing hook sleeve is fixedly connected to the sleeve installation support, the sleeve installation support is fixedly arranged inside the crash box, the rear end of the crash box is fixedly connected to the front installation plate, the front installation plate, the rear outer plate and the rear installation plate are fixedly connected together, and the rear installation plate is fixedly connected to a longitudinal beam of the vehicle. The vehicle towing hook traction device has the advantages that the connection is strong and effective, the carrying capacity is great, the manufacturing cost is low, the connection is convenient, the installation and maintenance are convenient, the great traction strength is guaranteed, the interference to peripheral equipment does not occur, and great practicability and market application value are achieved.

The invention relates to a vehicle body front longitudinal beam structure, and belongs to the technical field of vehicle design and manufacturing. The vehicle body front longitudinal beam structure comprises a front longitudinal beam assembly, an upper edge beam assembly, a front longitudinal beam connecting plate assembly, an upper edge beam front section assembly, a front anti-collision beam energy absorption box assembly and a front anti-collision beam assembly. According to the vehicle body front longitudinal beam structure, the force transmission path is optimized, the energy absorption capacity of the front end of the vehicle body is effectively improved, the load of the cabin longitudinal beam is reduced, the invasion amount of a front cabin to a passenger cabin is reduced or avoided, and the safety of a driver is improved.

The invention discloses a circular prestressed support system for subway connection channel construction and an assembling method, and belongs to the technical field of underground engineering. The circular prestressed support system for subway connection channel construction is simple and stable in structure, excellent in performance and good in engineering applicability, can be widely applied to freezing construction of subway connection channels. The circular prestressed support system for subway connection channel construction comprises a plurality of prestressed supports, wherein the adjacent supports are connected through connecting pieces, the prestressed support comprises a plurality of first arc-shaped prefabricated pieces, one second arc-shaped prefabricated piece, rigid buttresses and a jacking mechanism, and the first arc-shaped prefabricated pieces and the second arc-shaped prefabricated piece are connected end to end to form an annular support; the second arc-shaped prefabricated piece and the first arc-shaped prefabricated pieces on the two sides are all connected with the rigid buttresses, and the first arc-shaped prefabricated pieces separated from the second arc-shaped prefabricated pioece are further connected with the jacking mechanism.