128results about How to "Small swing" patented technology

The invention discloses a ship stabilization crane. The ship stabilization crane comprises a crane body, a lifting hook with a stabilization disc, folding stabilization arms and a lifting cable. The crane body is installed on a ship body, the lifting hook is connected with a main motor of the crane body through the lifting cable; the crane body self carries a stabilization device; the stabilization disc is fixedly connected to the lifting hook; the folding stabilization arms are symmetrically fixedly connected on the two sides of a crane jib in a hinged mode and controlled through hydraulic cylinders to expand and draw back; and the folding stabilization arms are connected with three lifting lugs in the circumferential direction of the outer wall of the stabilization disc of the lifting hook in the way that three additionally installed stabilization hydraulic motors and rollers are matched with corresponding steel wire cables and guiding pulleys, swinging is reduced in the way that movement of the corresponding motors is controlled to pre-tighten a stabilization rope, and traction stabilization of a stereoscopic triangle can be directly achieved through installation of equal division of circumference of the three lifting lugs. The ship stabilization crane is novel in structure, convenient to machine and use and safe and reliable and prevent a lifting tool and goods from swinging.

The invention discloses a wet-type electrostatic dust collector cathode and anode configuration structure. The wet-type electrostatic dust collector cathode and anode configuration structure comprises a cathode and an anode, wherein the cathode is installed on a cathode framework, the anode is installed on an anode framework, and the anode is in a regular-hexagonal tubular shape; the cathode is a cathode with discharging pins, the discharging pins are distributed on the cathode in a layering manner, each layer is provided with three discharging pins, adjacent layers are staggered to form an angle of 60 degrees, and the inter-layer distance is 25mm to 100mm; the discharging pins are vertically connected to the cathode, and each discharging pin points to the regular-hexagonal tubular corner of the anode. By adopting the wet-type electrostatic dust collector cathode and anode configuration structure, the anode can uniformly and effectively trap electrons and charged pollutants; voltage corona inception and corona stability of the cathode can be reduced, the discharging position of the cathode can be set according to the anode form, the length of each cathode discharging pin can be set according to the medium condition, the discharge intensity can be adjusted according to the angle, and simplicity and easiness can be realized; moreover, a needlepoint-shaped discharge point does not have the problem that the discharging is suppressed by the coating of dust and gypsum in the wet smoke; the cathode-anode configuration structure can be adaptive to a wet-type dust collector, and the application is wide.

The disclosed electronic percussion instrument includes a plate-like pad that has a front surface to be struck, a sheet-like pressure sensor that is provided on a back surface of an outer circumferential end portion of the pad and that detects a pressure change, and a weight portion that contacts a front surface of the pressure sensor, wherein, due to striking on the front surface of the pad, an inertial force from the front surface of the pressure sensor toward a back surface of the pad acts on the weight portion, and the weight portion presses the pressure sensor.

The invention discloses a high-speed optical fiber ring network communication network control topology of a large-capacity power electronic system. The control topology comprises a main node, multiple slave nodes, an on-off machine network, a fault protective network, a synchronization network and a high-speed data communication network. The control topology is high in communication speed, simple in structure, good in synchronization effect, high in distributed modularization and high in reliability.

The invention relates to a storage structure and a single-end low-swing bit line writing circuit. The circuit comprises at least one storage unit and a driving circuit, wherein the driving circuit comprises a first phase inverter (I1), and the input end of the first phase inverter (I1) is used for writing data (D). The circuit is characterized in that the driving circuit also comprises a first P-channel metal oxide semiconductor (PMOS) transistor (P1), a second PMOS transistor (P2), a first N-channel metal oxide semiconductor (NMOS) transistor (N1) and a second NMOS transistor (N2), the writing circuit also comprises a feedback control circuit, the storage unit comprises a third PMOS transistor (P3), a fourth PMOS transistor (P4), a third NMOS transistor (N3), a fourth NMOS transistor (N4), a fifth NMOS transistor (N5) and a sixth NOMS transistor (N6). The assistance of additional reference voltage or power supply voltage is not needed for realizing the low-swing technology, and in addition, the single-end single-swing writing is supported through the improved storage unit.

The invention provides a high-speed current switch driver based on MOS current-mode logic. The driver comprises: a MOS current-mode logic latch circuit for receiving current switch drive signals, and performing latching and amplitude limiting on the current switch drive signals so as to synchronize the current switch drive signals; a MOS current-mode logic current switch for receiving signals processed by the MOS current-mode logic latch circuit, generating current source drive signals with amplitude limited and adjusting crossing points of the current switch drive signals; and a common-source and common-gate current source with a NMOS switch for receiving the current switch drive signals processed by the MOS current-mode logic current switch and outputting low-distortion current signals, thus synchronizing the current switch drive signals and reducing feed-through effect.

The invention relates to a method for controlling the outer loop power of a mobile terminal in a code division multiple access (CDMA) mobile communication system. The method comprises the following steps: recording the target error block rate distributed for each transmission channel of the mobile terminal by the system; according to the target error block rate of each transmission channel, setting initial target signal-to-noise ratio corresponding to the transmission channel; recording the decoding result of the mobile terminal on each transmission channel during the transmission time interval; according to the decoding result, adjusting the target signal-to-noise ratio of each transmission channel one by one; according to the target signal-to-noise ratio corresponding to each transmission channel of the mobile terminal, determining the target signal-to-noise ratio controlled by the inner loop power; and according to the determined target signal-to-noise ratio, setting the threshold controlled by the inner loop power. By adopting the method for controlling the outer loop power of the mobile terminal in the CDMA mobile communication system, the crosstalks between mobile terminals can be reduced, the large swinging of the transmission power of the base station can be avoided, the capacity and stability of the system can be increased, the system is easy and fast to operate, the working performance is stable and reliable, and the method has wide application range.

An unequal-amplitude material cleaning sieve comprises a frame, a motor, a vibrating sieve, a feed inlet, a discharge outlet and a vibrating mechanism. The motor and the vibrating mechanism are respectively fixed on the frame, and the front end and the rear end of the vibrating sieve are respectively connected with the vibrating mechanism which is connected with the motor through a transmission mechanism. The vibrating mechanism comprises a pair of front eccentric wheels, a pair of rear eccentric wheels, a pair of front multistage link rods and a pair of rear multistage link rods, the front eccentric wheels and the rear eccentric wheels are driven by the transmission mechanism, the frame is rotationally connected with the front eccentric wheels as well as the rear eccentric wheels, the eccentric distance of each front eccentric wheel is larger than that of each rear eccentric wheel, each front multistage link rod is of a three-stage link rod structure, and each rear multistage link rod is of a two-stage link rod structure. Due to the fact that the vibrating sieve is driven to vibrate by the eccentric wheels and the multistage link rods, and the front link rods and the rear link rods are different in stage number, vibration directions of a sieve surface are diversified and better sieving effect can be achieved.

The embodiment of the application discloses an image source module, a waveguide, a near-eye display system and a control method thereof. An eye tracking module monitors the rotation angle of the eyesof a user in real time so as to determine an area corresponding to the field of view of the user on an image, and generates and sends an adjustment signal to the image source module and / or the waveguide to adjust an emergent beam. The adjusted beam can only display the image in the field of view of the user during imaging display, so that the interference of the displayed content to the user can be reduced while the power consumption of the system is reduced.

The invention relates to a high speed boat, and belongs to the technical field of shipping. A boat body of the high speed boat is provided with a fore peak, a passenger compartment and an engine room from head to tail. The dead rise angle of the fore peak is 38-42 degrees. The cross section of the passenger compartment is in a folded angle form, and the outline of the cross section of the passenger compartment is formed by sequentially connecting two lateral sides of two broadsides of the boat body, a bottom side, a first folded side and a second folded side, the bottom edge, the first folded side and the second folded side are located at the bottom of the boat body and arranged sequentially from bottom to top, the bottom side and the second folded side are horizontally arranged at the bottom of the boat body, the bottom side is arranged in the center of the bottom of the boat body, and the second folded side and the lateral sides are adjacent and arranged at the sides of the bottom of the boat body. The included angle between the first folded side and the bottom side and the included angle between the first folded side and the second folded side are both 150-160 degrees. The included angles between the second folded side and the lateral sides are 100-110 degrees. The high speed boat has the advantage of being high in speed.

The invention discloses a power generation system based on pressure constancy. The power generation system based on the pressure constancy comprises a high-pressure gas system, a gas-liquid mixing system, a hydraulic generator set, a channel switching system, a control system and a water flow compensation pressure circulation system, wherein the high-pressure gas system, the gas-liquid mixing system, the hydraulic generator set and the water flow compensation pressure circulation system are connected through the channel switching system, and are controlled through the control system. A water pump pumps water and compresses air in a variable-pipeline-characteristic down-conversion operation mode so that the water pump can operate near an efficient area all the time, the high efficiency is maintained, and electric energy consumed by water pumping of the water pump is reduced; a water turbine is stabilized near a rated water head in the power generation process so that the water turbine can operate near the highest efficiency area, and more electric energy is generated; and therefore, by consuming less electric energy, more electric energy is increased, so that the overall efficiencyfor converting power into power of the system is higher. The system has the functions of conventional compressed air energy storage and pumped storage power station large-scale electric energy storage, and has the characteristics of no dependence on terrain fall, high efficiency, long operation time and the like.

The invention provides an envelope tracking power supply with broadband output. The envelope tracking power supply comprises two paths of Buck converters, an AB-class linear amplifier and a control circuit, wherein the AB-class linear amplifier and the two paths of Buck converters are mutually connected in parallel; an output end of the AB-class linear amplifier is connected with a load in parallel; an output filter inductor of the first Buck converter is directly connected with an input end of the load; the output filter inductor of the second Buck converter is connected with a positive end of the output of the AB-class linear amplifier; the two paths of Buck converters and a negative end of the output of the AB-class linear amplifier are connected to the ground respectively; the control circuit comprises a logic gate circuit, two paths of current controllers and a third hysteresis comparator; each of the two paths of current controllers comprises a sampling circuit, an amplifying circuit and a hysteresis comparator; and the logic gate circuit comprises an AND gate and an NOT gate. The two paths of Buck converters are connected in parallel to provide a current to the load; the amplitude of oscillation of an output current of the linear amplifier is reduced; and the system efficiency is improved.

The invention discloses a knitting machine needle selector driven by piezoelectric ceramic sheet. Said needle selector is formed from machine frame, piezoelectric ceramic driving sheet, positioning plate, needle-selecting blade, latch and cover plate. Said invention adopts the symmetric and parallel type piezoelectric ceramic sheets, and provides its concrete structure, and its working principle and its operation steps.

The invention discloses a fixed-wing unmanned aerial vehicle PID parameter control method based on an ant colony algorithm. The method comprises steps of setting ant colony search nodes, defining the value range of the PID controller parameters: the scale factor Kp, the integration time Ti and the derivative time Td by the empirical method, and setting the search nodes to an N* 3 search point matrix set of one parameter per line, where N is the number of random values within the range of values greater than 1; adding the pheromone evaporation mechanism to the ant colony optimization mechanism, and evaporating the pheromone on the optimal path of the ant colony search after each turn of iteration; and traversing the ant colony search nodes by using the ant colony optimization mechanism of pheromone evaporation to find the node satisfying the evaluation control performance index, wherein the evaluation control performance index is that the integral of the absolute error is the smallest. The method realizes the optimal PID parameter searching and setting of the fixed-wing unmanned aerial vehicle by using the improved ant colony algorithm, accelerates the searching process of the optimal solution, and is suitable for the multi-condition constrained type combinational optimization.

The invention discloses an anti-swing control method of an industrial crane. An encoder, a frequency converter and a swing preventing system are adopted to control the coordination work of all driving motors; a corner parameter, returned by the encoder, of a rotating shaft on an electric block is analyzed; the swing amplitude of a lifting object is analyzed; and the acceleration and the deceleration of large and small cars are synchronously controlled, so that the swing of the industrial crane in the lifting and transporting process is prevented. The method is simple in control, convenient to operate, small in crane swing amplitude and small in object lifting swing amplitude.

The invention discloses an array substrate and a driving method thereof, as well as a display device. The array substrate comprises a common voltage generating unit, a sequential control unit, a data voltage generating unit, a switch control unit and pixel units, wherein the switch control unit is connected with the common voltage generating unit, the sequential control unit, the data voltage generating unit, a common voltage wire and a data wire; at a current frame, the switch control unit is used for loading a common voltage signal onto the common voltage wire and loading a data voltage signal onto the data wire; at a next frame, the switch control unit is used for loading a common voltage signal onto the data wire and loading a data voltage signal onto the common voltage wire. The switch control unit is arranged for switching voltage signals loaded in the data wire and the common voltage wire, so that the polarity-reversal requirement of liquid crystal molecules in the display device is met; meanwhile, the array substrate can be used for reducing the output voltage swing of the data voltage signals, so that the power consumption of the display device is reduced.

The invention discloses a CMOS digital to analog converter, mainly aiming to solve the problems of large switch noise, poor circuit precision and low speed of the traditional CMOS digital to analog converter under the condition of low power consumption. The CMOS digital to analog converter is composed of an input synchronization latch, a thermometer decoder, a delay equalizer, a latch, a current switch driver, an NMOS current source array and a band-gap reference voltage source, wherein the thermometer decoder adopts a parallel thermometer decoder structure and consists of an AND gate / NAND gate logical unit and an OR gate / NOR gate logical unit of an MOS current mode logical structure; the delay equalizer comprises a reverse directional device of the MOS current mode logic structure; both the latch and the current switch driver adopt the MOS current mode logic structure; and the input end of the NMOS current source array is connected with the complementary output ends of the latch and the current switch driver so as to generate complementary output current. The CMOS digital to analog converter in the invention has the advantages of small output pendulum deflection and switch noise, high circuit precision and rapid working speed, and can be applicable to communication, signal processing and video processing systems.

The invention provides a signal enhancing board as well as a signal enhancing system and method. The signal enhancing board comprises a PCIE signal interface unit, a signal pre-processing unit, a signal enhancing processing unit, a conversion and transmission unit and an SAS signal interface unit, wherein the PCIE signal interface unit is used for receiving a PCIE signal from an external mainboard; the signal pre-processing unit is used for removing a shake in the PCIE signal received by the PCIE signal interface unit, resetting output parameters through a dial switch and transmitting the processed PCIE signal to the signal enhancing processing unit; the signal enhancing processing unit is used for enhancing the amplitudes of a rising edge and a falling edge of the PCIE signal, reducing the oscillation amplitude of the PCIE signal and transmitting the processed PCIE signal to the conversion and transmission unit; the conversion and transmission unit are used for converting the received PCIE signal into an SAS signal and transmitting the SAS signal to the SAS signal interface unit; and the SAS signal interface unit is used for sending the received SAS signal to an external hard disk backboard. According to the signal enhancing board as well as the signal enhancing system and method, the PCIE signal between the mainboard and the hard disk backboard can be enhanced.

The invention provides a data reading method of a memory circuit and a data writing method of the memory circuit. A global memory array is adopted in the memory circuit; a multi-stage and multi-segment mode is adopted by the global memory array; the global memory array is divided into a group memory array and a segment memory array; the segment memory array comprises the group memory array and a group amplifying gate circuit; the global memory array comprises the segment memory array, a segment amplifying gate circuit and a global amplifying circuit; the global amplifying circuit is connectedwith the segment amplifying gate circuit through a global bit line; the segment amplifying gate circuit is connected with the group amplifying gate circuit through a segment bit line; the group amplifying gate circuit is connected with a memory unit in the group array through a group bit line; and through the multi-stage and multi-segment mode, the occupied area of a memory can be small and the swing amplitude of bit line voltage can also be effectively reduced in the layout, so that the aim of reducing power consumption is fulfilled. During data reading and writing operation, the operation is only required to be performed aiming at the currently selected bit line when the global memory array is adopted, so that the reading and writing speed of a memory can also be effectively increased.

The invention provides a container loading, unloading and stockpiling system. A stereoscopic warehouse type container warehouse is provided in the system, a traditional open storage yard is replaced, and the number of storage yards of containers and the unit area utilization rate of a site are increased. A four-layer stepped transfer platform is further arranged on the two sides of the outer portion of the stereoscopic container warehouse, a trailer wagon capable of moving rapidly, roadway shuttle cars and satellite cars are arranged on the transfer platform, traditional unmanned container trucks or AGVs are replaced, the distance between quay cranes and storage yards is greatly shortened, and the loading and unloading efficiency is greatly improved. The multiple roadway shuttle cars and satellite cars are arranged in the stereoscopic container warehouse. Meanwhile, the invention further provides a control method. Under control of a central control room computer system, all mechanisms only conduct single-function operation and can be seamlessly connected and cooperatively work, any container can independently enter a stereoscopic goods shelf quickly without moving any other container, and operation of container overturning and dumping of a traditional storage yard is avoided.

A voltage comparator contains low voltage devices (e.g., bipolar or MOS transistors) and high voltage devices (e.g., DMOS transistors). The low voltage devices, which cannot sustain a voltage greater than a relatively small range of variation that is substantially less than the range of potential variation of the input voltage, are connected in a differential amplifier configuration to perform precision differential measurements on the input voltage. The high voltage devices are interconnected with the low voltage devices in a manner that enables operating levels of the low voltage devices to move up / down, or ‘slide’, with variations in the input voltage, so that the low voltage devices are effectively immune to high levels of the input voltage.

The invention provides a single-phase oil-immersed transformer and a special iron core therefor. The single-phase oil-immersed transformer comprises a box body with a box cover, an iron core, a radiating pipe, an oil conservator, a lifting mechanism, a power mechanism and an oil tank, wherein the iron core is a single-frame dual-core column with a groove, is arranged at the center of the box body and is immersed by an oil body; a coil is led out of the box cover; a high-voltage insulating sleeve and a low-voltage insulating sleeve respectively sleeve a lead; the radiating pipe is arranged on the side wall of the box body; the oil conservator is arranged at the upper end of one side of the box body; the lifting mechanism is arranged below the iron core; the bottom end of the lifting mechanism is fixedly connected with the box body; the power mechanism is connected with the lifting mechanism; the oil tank is connected with the power mechanism; and the oil tank is arranged outside the box body. The single-phase oil-immersed transformer can drive the lifting mechanism to take out the iron core by taking the oil in the box body as a power source through the power mechanism and stores the oil in the box body into the oil tank, so that maintenance of the iron core and oil-change operation are facilitated; the cost is saved; and the maintenance efficiency is also improved.

The invention discloses a drilling method capable of improving drilling precision. The method comprises the following steps that a production plate is arranged on a drilling machine table board in analigned manner; an ultra-short edge drill bit is used for drilling a blind hole in the position, required to be subjected to through hole drilling, of a production plate, and the bottom of the blind hole is located in a medium layer below surface copper; the edge length of the ultra-short edge drill bit is smaller than the thickness of the production plate; a long edge drill bit with the same edgediameter the same as the ultra-short edge drill bit is used for continuously drilling downwards and drilling through the production plate on the basis of the blind hole, and a through hole is formed;the edge length of the long edge drill bit is larger than the thickness of the production plate; through the method, the drilling precision can be effectively improved through the two-time drilling manner, the drilling precision of a micro drill (the drill bit diameter is smaller than or equal to 0.3 mm) is improved to the maximum degree, and the drilling requirement with the drilling precision smaller than or equal to 2mil is met.

The invention discloses a grid driving unit, a row grid scanning driver, a driving method of a grid driving unit and a driving method of a row grid scanning driver. The grid driving unit comprises a signal input module, a negative pressure module, an inverter module, a cascade output module, and a scanning output module. Through the negative pressure module, the grid driving unit can function normally only through a single negative power supply, so requirements of the design of an external circuit are reduced, the structure of the circuit is simplified, the amplitude of circuit level is reduced, and power consumption of the circuit is reduced. Meanwhile, the circuit adopts a double-side driving configuration, so aesthetic demands of a narrow frame can be realized. Multiple grid driving units are connected in series and are connected with corresponding driving time sequences to form the row grid scanning driver, a single-side driver needs three driving clock signals, a two-side driver needs six driving clock signals, streamline type driving time sequences are adopted, and duty ratios are all 16.7%. Grid voltages are increased through capacitance coupling in the cascade output module, and in the negative pressure module, negative pressure attenuation characteristics facilitate applications in high-resolution display.

The invention discloses an acoustic vibrating toothbrush which comprises a main body shell (10), wherein a front panel (13) and a rear panel (9) are respectively arranged on the front side and the rear side of the main body shell (10); a cap component (71) a base component (72) are respectively arranged at the top end and the bottom end of the main body shell (10); a movement component (5) is arranged in the inner cavity of the main body shell (10); a brush head (1) is connected to the movement component (5); and the brush head (1) runs through the cap component (71) from the inner cavity of the main body shell (10) and extends to the upper part of the main body shell (10). The acoustic vibrating toothbrush disclosed by the invention, by virtue of the movement component having a bending radian and the main body shell, can be used for weakening vibrating intensity transferred from a motor to a hand-held part, improving vibrating intensity and frequency from the motor to the brush head, avoiding a vibrating sense transferred to the held part and enhancing the comfort in the hand and teeth of a user; the acoustic vibrating toothbrush conforms to the kinesiology principle perfectly, and the toothbrush is efficient in cleaning and caring teeth, compact in structure, energy-saving and environment-friendly.

The invention discloses a full-function trolley electrical control system based on a lifting trolley. The full-function trolley electrical control system comprises a lifting tool body, and further comprises a pair of reel hoisting mechanisms symmetrically arranged above the two ends of the lifting tool body, four sets of three-in-one auxiliary anti-swing reel mechanisms arranged above the four corners of the lifting tool body and an electronic control mechanism used for controlling the reel hoisting mechanisms and the four sets of the three-in-one auxiliary anti-swing reel mechanisms, whereineach reel hoisting mechanism comprises a hoisting rope and a main reel; each three-in-one auxiliary anti-swing reel mechanism comprises an auxiliary rope, an auxiliary reel and an auxiliary three-in-one mechanism; and the electronic control mechanism comprises a rectification unit, a brake unit, a hoisting mechanism frequency converter, an auxiliary three-in-one mechanism frequency converter, a main PLC and a driver control unit. The invention further discloses a full-function trolley electrical control method based on a lifting trolley. According to the full-function trolley electrical control system based on the lifting trolley and the full-function trolley electrical control method based on the lifting trolley, the dual hoisting synchronized operation of a crane is realized, and the anti-swing performance index of a lifting tool of the crane is improved.

The invention relates to a power line vibration absorber which mainly comprises a vibration absorbing rod, sensing barrels and a connecting rod. The connecting rod rotatably sleeves a fixed rotating shaft which is mounted on a pole tower, one end of the connecting rod sleeves a cable in an annular fastening manner while the other end of the same is fixedly connected with the vibration absorbing rod which is made by a permanent magnetic material, a magnetic field of the permanent magnetic material is parallel to axis of the vibration absorbing rod, the vibration absorbing rod is perpendicular to a plane where the connecting rod and the cable are positioned, the sensing barrels are arranged at two ends of the vibration absorbing rod in a sleeved manner, the two ends of the vibration absorbing rod are not exposed out of the sensing barrels respectively, the vibration absorbing rod does not contact with each sensing barrel, and each sensing barrel is a cluster of coaxial closed coils and is fixedly mounted on the pole tower. The power line vibration absorber can effectively reduce vibration transmitted to the pole tower by the cable, so that loosening of screws of the pole tower is prevented effectively; wear between the cable and the pole tower is reduced, and service life of each of the cable and the pole tower is prolonged.

The invention discloses a bearing-area-adjustable oil drum moving tool. The bearing-area-adjustable oil drum moving tool comprises a connecting block, a pull rod, supporting assemblies and a length-adjusting lengthening assembly. One end of the pull rod is hinged to one side face of the connecting block. The lengthening assembly comprises a fixing block and a plurality of lengthening strip blocks. One end of the fixing block is connected with the other side face of the connecting block. The end, away from the connecting block, of the fixing block is detachably connected with one end of one lengthening strip block. The multiple lengthening strip blocks are in detachable series connection with one another in sequence. The upper surface of the fixing block and the upper surface of the connecting block are connected with one supporting assembly correspondingly. Rollers are arranged on the lower surface of the fixing block and the lower surfaces of the lengthening strip blocks. According to the need, the lengthening strip blocks with the appropriate quantity are selected to be connected in series, and then a plurality of oil drums are placed on the supporting assemblies correspondingly. A carrying car is simple in structure, convenient to use, working efficiency of a worker is improved, and labor strength of the worker is relieved.

The present invention addresses the problem of providing a stent that can be designed to have a small mesh size without sacrificing diameter reducing properties and conformability to a curved shape, and is capable of preventing, when placed in a tubular organ, restenosis caused by intrusion of a tumor tissue into the lumen. The stent according to the present invention is configured from: a first weave structure (10) in which circumferential units (11-13) each comprising a plurality of circumferentially arranged mesh openings are disposed in the axial direction; and a second weave structure (20) in which circumferential units (21-23) each comprising a plurality of circumferentially arranged mesh openings are disposed in the axial direction to correspond to the circumferential units (11-13) of the first weave structure (10). The circumferential units of the second weave structure (20) are offset by 1 / 4 of the pitch in the circumferential direction relative to the corresponding circumferential units of the first weave structure, and interwoven with the corresponding circumferential units of the first weave structure. The second weave structure (20) is configured so that the bending part of one of each pair of adjacent circumferential units thereof is not interlocked with the bending part or wire intersection of the other circumferential unit.