8results 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.

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.

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 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 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 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.