9results about How to "Improve mechanical structure strength" patented technology

The present invention discloses a device, a sample and a method for detecting the dynamic mechanical properties of materials, and belongs to the field of dynamic mechanical properties test of materials. The middle part of the sample is an electromagnetic force stretching section, and a transition section, a high-speed stretching section and a clamping section are respectively extended outward from both ends of the electromagnetic force stretching section in sequence. The larger width of the electromagnetic force stretching section is transitioned to the smaller width of the high-speed stretching section through the transition section. The device is based on electromagnetic forming technology and online measurement technology. The electromagnetic forming charge and discharge system controls the charge and discharge of the electromagnetic forming coil. During the detection process, the uniform magnetic field formed by the electromagnetic forming coil applies a uniform electromagnetic force to the electromagnetic force stretching section; a high-speed camera is used to collect the deformation of the high-speed stretching section, and a strain collector collects the strain of the transition section. The dynamic mechanical properties of various materials can be measured in real time and directly, and it has the advantages of wide test range, good test stability, high test accuracy, good repeatability, long equipment life, short test cycle and low cost.

The utility model discloses a special-shaped steel pipe and an engineering machinery cab. The section of the special-shaped steel pipe is of a closed structure formed by a plurality of line segments. A first step is arranged on the side, close to cab glass, in the closed structure, the opening direction of the first step faces the front windshield, and the step face of the first step is used for containing the cab glass. A second step is arranged on the side, close to the cab door, of the closed structure and used for assisting installation of the cab door; the opening direction of the first step is opposite to the opening direction of the second step. Due to the fact that the special-shaped steel pipe is a closed sectional material formed through cold bending, compared with a structure formed through welding, the special-shaped steel pipe has higher mechanical structural strength, meanwhile, the first step and the second step are arranged in the closed structure formed by the section of the special-shaped steel pipe, installation of cab glass and auxiliary installation of a vehicle door can be achieved, and meanwhile the service life of the vehicle door is prolonged. And a bearing plate for mounting the glass does not need to be welded, so that the overall safety is improved, and the manufacturing process is simplified.

The present invention discloses a multi-degree-of-freedom vibration test device and a test method thereof in an unbalanced field environment. The device comprises a bottom unbalanced field foundation, a multi-axial electric actuator, a decoupling device and an automatic centering system. The present invention adds an air tank between the air source and the airbag, changes the volume of the air tank to adjust the stiffness of the airbag, and enables the airbag to provide more preload force. When the rocking table is subjected to a tangential force, the greater the stiffness of the airbag, the smaller the offset of the table, and the normal operation of the multi-axial vibration test system in an unbalanced field environment can be achieved, while ensuring that the test waveform is smoother.

The invention relates to a doubly-fed wind generator grid connection and power direct vector control method, which comprises the following steps of: starting a doubly-fed wind generator, introducing direct current excitation to a rotor excitation winding, and detecting the output voltage frequency of the doubly-fed wind generator; when it is determined that the output voltage frequency is the same as the power grid voltage frequency, the direct-current excitation is disconnected, and the doubly-fed wind generator is connected with the power grid; after grid connection, an excitation power supply is connected, the voltage of an excitation winding is detected, and the voltage of the excitation winding is utilized to adjust the output voltage of the excitation power supply; and adjusting the output voltage of the excitation power supply to respectively carry out grid-connected reactive current control and grid-connected active current control of the doubly-fed wind generator. According to the invention, grid-connected operation of the doubly-fed wind driven generator without the rotating speed sensor is realized, and active power and reactive power control is effectively carried out; generator excitation winding voltage is synchronously tracked to realize generator grid-connected operation power control, and good dynamic control performance and high and low voltage ride through functions are realized.

The utility model relates to the technical field of endoscopes, in particular to an endoscope front end assembly and an endoscope, which comprise a front end head, a connecting pipeline, a snake bone unit and a fastener, the connecting pipeline is sleeved at the far end of the snake bone unit, and the near end of the front end head is sleeved on the connecting pipeline. According to the utility model, the connecting pipeline is utilized to realize diameter shrinkage at the joint of the front end head and the snake bone unit, so that the snake bone unit does not need to be matched with the near-end diameter of the front end head, the snake bone unit can be directly subjected to miniaturization design, meanwhile, the processing technology of the front end head and the snake bone unit can be simplified, the processing cost of the front end head and the snake bone unit is reduced, and the processing efficiency is improved. The contact area between the front end head and the connecting pipeline and the contact area between the connecting pipeline and the snake bone unit are increased, stress concentration is avoided, the mechanical structural strength of the endoscope front end assembly is enhanced, and therefore the use safety and stability of an endoscope are effectively improved.

This invention relates to the field of all-solid-state secondary battery technology and discloses a high-performance all-solid-state secondary battery equipped with a stabilized positive electrode, comprising a positive electrode, a negative electrode layer, and a solid electrolyte layer. The positive electrode is manufactured by coating and drying a slurry containing 80%-88% positive electrode active material, 10%-16% sulfide solid electrolyte, 1%-2% conductive agent, and 1%-2% binder, followed by a heat-pressurization treatment at 100℃-250℃ and 10MPa-100MPa. This invention constructs a dense interface stabilization layer in situ between the positive electrode active material and the sulfide electrolyte by applying a thermo-pressure coupling treatment to the positive electrode precursor. This stabilization layer improves the physical contact between the solid and solid interfaces and reduces interfacial impedance. Simultaneously, this stabilization layer acts as a physical barrier, inhibiting the oxidative decomposition of the electrolyte under high voltage, slowing capacity decay, and improving the battery's cycle life and structural stability.

The application discloses a high-reliability packaging structure of a Hall current sensor and a packaging method thereof. The structure comprises a substrate, a Hall current sensor chip and a through-flow sheet. The chip is inverted and buckled on the top surface of the substrate, and the chip and the through-flow sheet are electrically connected to the top surface of the substrate in a fixed connection mode. A ring frame and a cover plate are also fixed on the substrate. The cover plate covers the ring frame to enclose the space formed by the ring frame and the substrate. The through-flow sheet comprises a connecting part and a channel part. The connecting part is a certain distance away from the chip, and the channel part is insulated from the back surface of the chip and is used for leading a detection current into the sensing area of the chip.

The invention discloses a three-axle railway locomotive power model bogie and transmission device, comprising a gearbox, a frame connected to the outside of the gearbox, and a traction rod assembly connected to the bottom of the frame; wherein the gearbox comprises a gearbox control box at the top, a gearbox housing connected to three wheel groups, a power main shaft is arranged in the gearbox control box, one end of the power main shaft passes through the gearbox control box and is connected to a motor through a universal joint sleeve; a central speed change gear is connected below the shaft body of the power main shaft, the central speed change gear is connected to an intermediary gear set, and the intermediary gear set is connected to a coaxial power gear; the intermediary gear set and the coaxial power gear form an M-type output path, the number of the coaxial power gears is 3, they are located at the end of the M-type output path and at the wheel body positions of the three wheel groups respectively, and a recessed structure 1A and a recessed structure 1B are provided between the three wheel groups.

The utility model relates to the technical field of agricultural machinery, in particular to a box type front frame and a tractor. The box type front frame comprises a first connecting assembly, a second connecting assembly, two cross beam assemblies arranged oppositely and a reinforcing assembly. The first connecting assembly and the second connecting assembly are arranged at the two ends of the cross beam assembly in the length direction correspondingly to define a frame structure. The cross beam assembly is of a hollow box type structure. The first reinforcing piece is embedded in the cross beam assembly and is connected with two opposite inner walls in the cross beam assembly; the second reinforcing piece is arranged between the first connecting assembly and the cross beam assembly. The first reinforcing piece is arranged in the cross beam assembly, so that the mechanical structure strength of the front frame is improved while the weight and the cost are reduced, and it is guaranteed that the front frame has good bearing capacity; in addition, the bending resistance and the torsion resistance of the front frame can be further improved by arranging the second reinforcing piece, and therefore the reliability of the front frame is guaranteed.