18results about How to "Avoid fretting" patented technology

The application belongs to the technical field of combustion engines, and provides a large-size side exhaust pipe of a turboshaft engine, which comprises: a pipe body having an inlet end and an outlet end; an outlet reinforcing structure arranged at the outlet end region of the pipe body; a support structure arranged inside the pipe body; an anti-abrasion connecting structure arranged at the inlet end of the pipe body; and an internal flow passage of the pipe body is configured to guide the gas input from the inlet end to be discharged laterally at the outlet end, the internal flow passage of the pipe body has a preset expansion cone angle θ2, the flow passage center line of the pipe body is a three-dimensional space curve constructed based on a non-uniform rational B-spline curve, and the ratio of the outer diameter size of the inlet end to the center transverse distance between the inlet end and the outlet end satisfies a preset condition. The core aerodynamic problem of "complex internal flow field organization of a large-size side exhaust pipe, non-uniform outlet flow field and small effective aerodynamic area" in the prior art is solved, and the limit performance of the exhaust pipe is excavated without affecting the performance of the engine.

This invention discloses an intelligent modular composite milling and turning tool for machining centers, relating to the field of milling and turning tool technology. It includes a turret configured to be rotatably mounted on a machine tool turret base to perform multi-axis composite machining motions. The turret's disc body has a plurality of precision guide grooves arranged in a circumferential array extending radially. This invention constructs a closed fluid circulation loop comprising a spiral cooling pipe, a circulating pump, and a telescopic pipe, and incorporates an adaptive cooling assembly consisting of radial heat dissipation fins and a temperature sensor. This allows for real-time adjustment of coolant flow rate and heat dissipation power based on cutting heat, ensuring the tool holder remains in a constant-temperature machining environment. This effectively avoids dimensional errors caused by thermal deformation and improves the yield rate of machining heat-sensitive materials.

The present invention provides a double sliding field tibial platform base and gasket system, including a platform base and a gasket, wherein the platform base includes an upper platform and a lower keel, wherein two high dividing ridges are arranged in the middle of the platform from front to back, and the platform is divided into three parts: a central groove, an inner sliding field, and an outer sliding field, and the gasket is divided into a central gasket, an inner gasket, and an outer gasket, which are matched with the three parts of the platform, and the above structure is matched with an artificial femoral prosthesis to form an artificial joint interface in which both the inner chamber and the outer chamber are slidable and rotatable. The system can form a joint interface that can move flexibly in the inner and outer joint compartments after knee replacement, while retaining the front-back stability, dispersing and reducing the wear rate of the inner and outer compartments of the knee joint, improving the movement characteristics of the knee joint, improving the surgical effect, and extending the service life of the prosthesis.

This invention relates to the field of orthopedic repair technology, and provides a 3D-printed mortise-and-tenon composite drug-loaded femoral head necrosis reconstruction rod and its preparation method. The reconstruction rod includes a skeleton, the inner cavity of which has a three-dimensional, interconnected, micron-scale topological porous structure; both the outer surface of the skeleton and the surface of the micron-scale topological porous structure are covered with a drug composite layer; the outer surface of the skeleton has multiple tenons for forming a mortise-and-tenon lock with the inner wall of the femoral head medullary cavity; the drug composite layer contains a first drug that inhibits osteoclast activity and a second drug that promotes osteoblast differentiation. This invention achieves anti-rotation and anti-settlement mechanical locking with the host bone through a biomimetic mortise-and-tenon structure, and actively regulates the local bone repair microenvironment by loading dual drugs that inhibit osteoclast activity and promote osteoblast differentiation, ultimately achieving bio-integrated fixation mimicking natural bone.

This invention discloses a modular, environmentally friendly metal-enclosed switchgear, specifically relating to the field of power distribution switchgear technology. It includes: a mounting box, a cabinet, a first track, a second track, a slide rail, and a floating mechanism. The cabinet comprises a rectangular shell composed of multiple plates. An elastic reset structure is provided on the inner side of the rectangular shell. The rectangular shell deforms under the pressure of the mounting box, allowing the elastic reset structure to provide elastic support for the rectangular shell in the horizontal plane, thereby compensating for the assembly tolerance between the mounting box and the slot. This invention, by providing slide rails on both sides of the mounting box, which cooperate with the first and second tracks on the inner side of the cabinet, constitutes a stable dual-track guiding system. This significantly reduces the resistance during the insertion and removal of the mounting box, achieving nearly interference-free smooth sliding, thereby greatly reducing wear on the guide surface and contact surface, and extending the overall service life of the drawer module and the cabinet.

The utility model provides a head support for a neurointervention operation. The head support comprises cheek protection pads arranged on the left side and the right side of the head respectively and an afterbrain protection pad connected with the lower portions of the left cheek protection pad and the right cheek protection pad jointly. A supporting frame is fixed outside the cheek protection pad and the afterbrain protection pad, a height adjusting device is vertically connected to the lower portion of the supporting frame, a fork frame is fixed to the bottom of the height adjusting device, and the head support is installed on an operating bed through the fork frame. The shape of the cheek protection pad is improved, the head of a patient is wrapped and fixed from the side face of the patient, and auricle spaces are reserved to prevent auricles from being extruded. The air cushions are arranged at the positions, corresponding to the frontal bone and the mandible, of the cheek protection pad, protruding bones of the face can be clamped and fixed, the situation that the head can slightly move due to clamping of soft tissue is avoided, the forehead bandage and the jaw bandage are matched to fix the whole head of the patient, and the patient can be limited to rotate, tilt, pitch and other actions.

This utility model relates to the field of hoisting operation technology and discloses a hoisting pulley structure, including: a pulley body, a connecting bearing, a wheel and axle assembly, and a fixing assembly. The pulley body has a through groove; multiple connecting bearings are spaced apart in the through groove along the axis of the pulley body; the wheel and axle assembly passes through the connecting bearings, and the outer wall of the wheel and axle assembly is in contact with the inner wall of the connecting bearing; the fixing assembly includes: a pressing member and an expanding member. Multiple sets of receiving mechanisms are spaced apart along the axial direction on the side wall of the wheel and axle assembly. Each set of receiving mechanisms includes multiple receiving grooves spaced apart along the circumference of the wheel and axle assembly. The expanding member is disposed in the receiving groove. One end of the wheel and axle assembly has a pressing groove. The pressing member is disposed in the pressing groove and abuts against one end of the expanding member. The other end of the expanding member abuts against the inner wall of the connecting bearing. This utility model effectively prevents the relative slippage between the connecting bearing and the wheel and axle assembly by pushing the expanding member with the pressing member and pressing it against the inner wall of the connecting bearing, thus ensuring the operational stability of the pulley.

The utility model relates to a power battery frame middle longitudinal beam with a connecting piece and a commercial vehicle, and belongs to the technical field of power battery frames. The power battery frame middle longitudinal beam with the connecting pieces comprises a middle longitudinal beam body and connecting piece bodies, the connecting piece bodies are used for fixing the middle longitudinal beam body to an end beam of a power battery frame, and the two ends of each side of the middle longitudinal beam body are symmetrically connected with the connecting piece bodies through bolts. The contact face between the middle longitudinal beam body and the connecting piece body and the contact face between the connecting piece body and the end beam of the power battery frame are coated with structural adhesive.

The invention relates to a fuel roller pump clearance automatic control device which comprises a pump body and an eccentric sleeve, the pump body is clamped by a fixing device, a sliding table air cylinder and a precise sliding table are arranged on the two sides of the fixing device respectively, and the precise sliding table pushes the eccentric sleeve to move through a rear positioning plate and makes contact with a rotor in the pump. After parameters collected by the pressure sensor reach set values, the precise sliding table drives the rear positioning plate to reversely move by the distance of a set gap and be locked, and the sliding table air cylinder drives the front positioning plate to push the eccentric sleeve to move and make the eccentric sleeve make contact with the rear positioning plate. By the adoption of the technical scheme, the eccentric sleeve makes contact with the rotor in the pump to be at the zero position, the precise sliding table moves reversely, the rear positioning plate is locked after precisely moving by the needed spacing distance, at the moment, the gap between the rear positioning plate and the eccentric sleeve is the needed set distance, and at the moment, the sliding table air cylinder is controlled to be started in the other direction; and the clearance adjustment is completed by pushing the eccentric sleeve to contact the rear positioning plate.

The utility model provides a vehicle front axle assembly structure which comprises a front axle, a steering knuckle, a pin shaft and a thrust bearing, and the front axle is provided with a first pin hole; a second pin hole and a third pin hole are formed in the steering knuckle; the pin shaft is in interference fit with the first pin hole and is in clearance fit with the second pin hole and the third pin hole, and an inclined chamfer is formed in the end, close to the third pin hole, of the first pin hole. The pin shaft is sleeved with the thrust bearing, and the thrust bearing is located between the front shaft and the first pin hole. The pin shaft and the front shaft are in interference fit, the inclined chamfer is formed in the end, facing the thrust bearing, of the first pin hole of the front shaft, in this way, stress of the end of the first pin hole is reduced, the probability that the pin hole of the front shaft cracks is reduced, and therefore the application stability is improved, meanwhile, the inclined chamfer of the end of the first pin hole is filled with the elastic material, and the service life of the pin hole is prolonged. Therefore, foreign matters can be prevented from entering, and abrasion of the first pin hole and the thrust bearing can be prevented.

The utility model relates to the technical field of fixing clamps for machining, in particular to a fixing clamp for machining an automobile engine cover, which is accurate in positioning, synchronous in clamping, wide in applicability and convenient to maintain. Comprising a base plate, first sliding rails, a supporting frame and a plurality of clamping mechanisms, the first sliding rails are symmetrically arranged at the two ends of the base plate, the supporting frame is slidably arranged on the first sliding rails, and the clamping mechanisms are slidably arranged on the supporting frame; the clamping mechanism comprises a mounting block, a first connecting piece and a second connecting piece are arranged on the two sides of the mounting block, a lower clamping plate is arranged on the first connecting piece, a second driving mechanism is arranged on the second connecting piece, a third connecting piece is arranged on the second driving mechanism, an upper clamping plate is arranged at the bottom of the third connecting piece, and the second driving mechanism is used for driving the third connecting piece and the upper clamping plate to move in the vertical direction. A control valve is arranged in the second driving mechanism, and the action of the upper clamping plates of the multiple clamping mechanisms is synchronously controlled through the control valve.

The invention relates to the technical field of bearings, and discloses an adjustable-center sliding bearing assembly which comprises a bearing support forming an external supporting structure of the assembly. The bearing seat unit is at least partially accommodated in an inner cavity defined by the bearing support; the sliding bearing is mounted on the bearing seat unit, and an inner hole of the sliding bearing is used for accommodating and supporting a rotating shaft; the elastic aligning mechanism is arranged between the bearing support and the bearing seat unit, and is configured to provide elastic support and allow the bearing seat unit to deflect at multiple angles relative to the bearing support; the sphere center of the spherical matching pair is positioned on the axis of the sliding bearing; and the spherical matching pair and the elastic aligning mechanism act synergistically to jointly support the sliding bearing so that the sliding bearing can conduct self-adaptive angle deflection around the sphere center. Through collaborative design of the elastic aligning mechanism and the spherical matching pair, self-adaptive angle deflection of the sliding bearing is achieved, shaft system misalignment is accurately compensated, and the problem of eccentric wear is thoroughly solved.

The invention belongs to the technical field of medical instruments, and particularly discloses an acetabular prosthesis which comprises an acetabular cup mounted in an acetabular fossa. The acetabular cup and the filling block are connected in an embedded and clamped mode through the anti-rotation structure, and the acetabular cup and the filling block are fixed together through the first fixing nail. And the fixed wing is connected with the filling block and is fixed on the ilium wing. By means of the anti-rotation structure, when a patient implanted with the acetabular prosthesis moves and dislocation and slippage occur between the filling block and the acetabular cup, the first fixing nail cannot slightly move under the action of shearing force, the shearing force is borne by the anti-rotation structure, and the service life of the acetabular prosthesis is prolonged. According to the acetabular prosthesis, the first bone grafting groove and the supporting table are arranged on the filling block at intervals, the second bone grafting groove is formed in the acetabular cup, the weight of the acetabular prosthesis is reduced, autogenous bones or allogeneic bones of a patient can be implanted into the first bone grafting groove and the second bone grafting groove, the acetabular prosthesis is effectively prevented from loosening for a long time after being implanted, and the survival rate of the acetabular prosthesis is increased.

The invention discloses a filter element mounting structure of a filter concentrator, which comprises a filter element mounting pipe, the filter element mounting pipe is provided with a plurality of filter element mounting pipe side joints, and the end part of the filter element is provided with the filter element side joints; each filter element side connector is provided with an axial through hole capable of containing the corresponding filter element installation pipe side connector, the inner side end of each axial through hole is communicated with an inner cavity of the corresponding filter element, and the outer side end of each axial through hole extends to the end face of the corresponding filter element side connector. An inner threaded hole is formed in the hole channel of the axial through hole close to the inner side end, and a counterbore is formed in the hole channel close to the outer side end; the filter element installation pipe side connector is provided with a pipe nozzle capable of being contained in the corresponding axial through hole, an outer threaded rod matched with the corresponding inner threaded hole is formed in the outlet position of the pipe nozzle, a sealing ring installation flange matched with the corresponding counter bore is formed in the root position of the pipe nozzle, and the sealing ring installation flange is sleeved with a sealing ring. The problem that the threads are eroded by stock solution and impurities is solved, and the filter element is convenient to install and replace.

The invention provides a pin conductor capable of preventing tin whisker and fretting wear, which is provided with a core material made of copper or copper alloy, and a nickel layer and a tin-silver-copper alloy layer which are sequentially coated outside the core material, and the tin-silver-copper alloy comprises the following components in percentage by weight: 2-4% of silver, 0.2-1.0% of copper and the balance of tin; the invention also provides a manufacturing method of the pin conductor capable of preventing tin whisker and fretting wear, which comprises the following steps: sequentially carrying out deformation processing, electroplating of the middle nickel layer and hot dipping of the tin-silver-copper alloy layer on the high-strength and high-conductivity copper or copper alloy conductor material, and then carrying out cold deformation processing to draw the whole conductor material. The binding force between the core material and the plating layer is further improved, the hardness and wear resistance of the pin conductor are improved, tin whiskers are effectively prevented from being generated in the use process of the pin conductor, and meanwhile fretting wear is reduced.

The invention discloses a mechanical locking hydraulic oil cylinder, which relates to the technical field of hydraulic devices, and comprises a cylinder body assembly and a locking assembly I, the cylinder body assembly comprises a cylinder body, a piston rod, a communicating pipe, a sliding barrel, a check block and a second spring. The piston rod and the sliding barrel are arranged in the cylinder body in a sliding manner; the first locking assembly comprises a fixing ring and a limiting piece. The limiting piece comprises a first telescopic rod, a first spring and a clamping block. A baffle block and a fixing ring are fixed on the piston rod; two ends of a telescopic rod I are respectively arranged on the fixing ring and the telescopic rod I; the sliding cylinder is located between the two check blocks. Piston rod slippage caused by internal leakage of a hydraulic system can be completely avoided through a mechanical locking mechanism, and the reliability and safety of equipment are improved; in the shutdown state, the clamping block is completely attached to the check block, friction force is generated, and the piston rod can be effectively prevented from accidentally extending outwards; the electromagnetic valve and the second spring enable the sliding cylinder to automatically reset during shutdown.

The utility model discloses rocker arm type hydraulic swash plate carburized plane high-precision machining technological equipment, and relates to the technical field of high-precision machining, the rocker arm type hydraulic swash plate carburized plane high-precision machining technological equipment comprises a hot plane accurate grinding machining clamp and a grinding device, the grinding device is arranged on the front side of the hot plane accurate grinding machining clamp, and the hot plane accurate grinding machining clamp comprises a connecting plate; and a positioning seat is fixedly mounted in the middle of the front side of the connecting disc. According to the utility model, the fixed seat I is in arc surface contact with the arc self-alignment positioning block, so that the positioning tooth surface of the arc self-alignment positioning block can adapt to the characteristic that the blank surface of the end surface of the swash plate part has pattern draft, and the contact surface is increased; under the action of the second pressing screw, the inclined wedge type pressing block translates in the direction away from the fixing base, the machined swash plate part is jacked through the translation distance, and the center auxiliary pressing block presses the swash plate part under the action of the first pressing screw to prevent the swash plate from slightly moving upwards in the machining process.

The utility model relates to the technical field of hydraulic systems, in particular to a two-way stop reversing valve and a pressure relief structure thereof. The pressure relief structure comprises a first valve sleeve and a second valve sleeve, wherein a first valve port, a second valve port and a liquid drainage port are formed in the first valve sleeve; the main valve element and the pilot valve element are movably arranged in the first valve sleeve, and a first liquid channel connected with the first valve port and the second valve port is formed in the main valve element; a pressure relief channel communicated with the first liquid channel is formed in the second valve sleeve, the pilot valve element is in sliding connection with the second valve sleeve, and the pilot valve element slides along the second valve sleeve to achieve communication or cut-off of the liquid drainage opening and the pressure relief channel. The two-way cut-off reversing valve comprises the pressure relief structure and a driving part used for driving the pilot valve element to move in the second valve sleeve. The technical problems that in the prior art, a pilot valve element is closed in the moving space between a valve sleeve and a main valve element, hydraulic impact in a two-way stop reversing valve is difficult to effectively buffer or release, and switching is stuck or response is slow are solved.