33results about How to "Unified design" patented technology

The invention provides a volume design method for asphalt mixture with skeleton dense structure, which is a method for mixture proportion design. The method comprises: step 1, according to the regulation of the current specifications, the densities of asphalt material and aggregates of various grades are determined; step 2, the void-filling rate V0, when the mixture is solely composed by the aggregate of the coarsest grade with the diameter of D0 in the asphalt material, is tested, and the theoretical gradation of the coarse aggregate is calculated; step 3, the theoretical densities and the integral density of the coarse aggregates and fine aggregates in the asphalt material are respectively confirmed; step 4, compact stacking density of the coarse aggregate and the void ratio VCA when the coarse aggregates are in a state of compact stacking are confirmed; step 5, the proper volume parameters and value of VMA and VV are chosen according to the maximum particle diameter of the asphalt material; step 6, the usage amount of the coarse aggregates, fine aggregates and asphalt in the asphalt material is determined according to the theoretical formula for asphalt mixture volume design so as to determine the mixture gradation. The completion of the volume design of the mixture is a key technical measure to improve the high-temperature property of the asphalt pavement.

A predictive and self-tuning PI controller includes an apparatus for variably assigning gains thereto in accordance with specified time functions following a change in set-point. The control gains are computed in accordance with a plurality of input parameters and subsequently continuously adjusted to set-point errors based on a GPC approach thereby to optimize performance indices derived from simple and classical user specifications. Variation and tuning of control gains in accordance with set-point errors permits the PI controller to be useful in the general area of process control and applicable to a wider range of processes compared to traditional PI control, including time-delay processes, unstable processes and processes with time-varying dynamics.

The invention discloses a wind power dedusting system for a rolling process of a cigarettes factory. The wind power dedusting system comprises a deduster connecting pipe, a plurality of branch wind pipes and a plurality of pieces of rolling and packing equipment, wherein each piece of rolling and packing equipment is connected with a branch wind pipe; the wind power dedusting system also comprises a wind compensating pipe with a wind compensating silencer and a main wind pipe; the deduster connecting pipe and the wind compensating pipe are respectively communicated with the main wind pipe; the main wind pipe is respectively communicated with each branch wind pipe through a pipe collector; and the wind compensating pipe is provided with a control valve which is used for automatically switching on to compensate wind when a certain branch wind pipe is stopped. The wind power dedusting system can concentrate wind power for supply, and ensure stable wind quantity, wind pressure and wind speed; the pipeline design is more standardized and unified; and the effective operability and the yield of the rolling and packing equipment are improved, the production cost is reduced and the service environment of workers is improved.

The invention discloses a continuous ion exchange device and a continuous ion exchange method for extracting gallium from Bayer mother solution. The device comprises resin, a resin column for loading the resin, a discharge main pipe communicated with the upper end of the resin column and a feeding main pipe communicated with the lower end of the resin column, wherein the resin column comprises at least four resin column groups connected in series; the feeding main pipe comprises a Bayer mother solution feeding main pipe, a washing feeding main pipe, a flushing feeding main pipe and a transition feeding main pipe; the discharge main pipe comprises a Bayer mother solution discharge main pipe, a washing discharge main pipe, a flushing discharge main pipe and a transition discharge main pipe; each resin column group is provided with a feeding branch pipe communicated with the feeding main pipe and a discharge branch pipe communicated with the discharge main pipe; and each feeding branch pipe and each discharge branch pipe are provided with a control valve for cooperatively controlling the resin column groups to implement ion exchange, washing, flushing and resin transition processes in turn respectively. The method has the advantages of simple equipment, convenient operation and high automation degree.

The invention discloses a primary machining method for a baseline of a bearing frame casting piece of an oblique support plate. The primary machining method comprises the following steps: (1) taking the end face A of a rear mounting side of an outer ring as an axial baseline, taking an inner hole B of a front mounting side of an inner ring as a radial baseline of a casting piece, and taking the center C of the oblique support plate as an angular baseline; and (2) leaving 3 mm of margin at the baselines of the A and the B, wherein the surface smoothness is Ra3.2, and the dimension precision ofthe baselines of the A, the B and the C is + / -.1 mm. The primary machining method disclosed by the invention integrates design, casting and the baselines for machining, realizes a high positioning precision, can be used for rapidly and accurately measuring the dimension of the bearing frame casting piece of the oblique support plate, improves the dimension precision of the casting piece, improvesthe machining efficiency and increases the machining capacity.

The invention discloses a road cement concrete pavement strength index evaluation method. During rating of a field pavement slab, test results of the flexural strength of a joist test sample, the splitting tensile strength of a molded cylindrical test sample and the splitting tensile strength of a core sample decide whether the strength of the field pavement slab meet a requirement or not. For a low-grade road, just whether the molding splitting tensile strength meets the standard or not needs to be verified. For a high-grade road, the concepts of the molded cylindrical test sample and the molding splitting tensile strength are introduced, a comparison test for the molding splitting tensile strength, the splitting strength of the core sample and the flexural strength is performed through an indoor test, a mutual relation expression of the flexural strength, the molding splitting tensile strength and the splitting strength of the core sample is established in a regression way, the conventional conversion relation expression of the flexural strength and the splitting strength of the core sample is updated, the molding splitting strength converted from the splitting strength of the core sample is taken as a supplement index during acceptance, and a comprehensive strength index rating system is established to be taken as a rating basis for engineering quality acceptance.

The invention discloses a server supporting cascade connection of multiple backboards. The server comprises a mainboard, the mainboard is provided with a BMC, a mainboard low-speed connector, an Expander chip and a plurality of mainboard high-speed connectors, the BMC is connected to the mainboard low-speed connector through an I2C bus, and the BMC is connected to the Expander chip through the I2C bus; a plurality of backboards, each backboard is provided with an I2C repeater, a backboard low-speed connector and a backboard high-speed connector, the backboard low-speed connector and the backboard high-speed connector are connected with the I2C repeater, the multiple backboard low-speed connectors are sequentially connected in series and then connected with the mainboard low-speed connectors, and each backboard corresponds to one mainboard high-speed connector, each backboard high-speed connector is connected with the corresponding mainboard high-speed connector and then is connected to the Expander chip; the BMC is configured to detect the in-place backboards and enable the I2C repeater of any in-place backboard, and the backboards where the enabled I2C repeaters are located serve as gated backboards. The server provided by the invention solves the problem of duplicate I2C addresses of cascaded backboards, improves the polling efficiency of the BMC accessing the backboard equipment, and reduces the load of the I2C bus.

The invention discloses a cassette optical line terminal equipment multiple passive optical fiber network card chip number identification method. The method includes the following steps:1, the number of slot identification code signals required by the whole backplane is determined; 2, the backplane is designed to make the backplane has an enough space to place a pull-up resistor and / or a pull-down resistor for configuring slot identification code levels and has enough pins to connect a master control board and passive optical fiber network chips; 3, the pull-up resistor and / or the pull-down resistor are set according to the voltage of the backplane to configure different levels for each slot identification code signal; 4, and the passive optical fiber network chips are distinguished through the voltage difference between the slot identification code signals. According to the invention, the purpose of passive optical fiber network chip distinguishing is realized on the backplane of cassette equipment, and advantages of low overall design difficulty, reduced production cost and convenient post-maintenance and preservation can be realized.

A cable integrated device for an electric bicycle comprises a partition board, as well as a bottom housing and a housing plate which are respectively connected with the two surfaces of the partition board, wherein a PCB insertion chamber, which is used for arranging a PCB and forms a secondary water-proof structure, is formed in the bottom housing; the PCB is fixed on the partition board; the partition board and the housing plate together form a primary water-proof sheath cable chamber; more than two upper part wire-in holes, communicated with the sheath cable chamber, are formed in the upper end of the connection part of the partition board and the housing plate, and lower-part wire-out holes, which are communicated with the PCB insertion chamber and allow cables connected with a controller to penetrate, are formed in the lower part of the partition board; and two wire slots, used for accommodating brake cable steel wires or mechanical shift speed regulation wires, are respectively formed in the connecting wires of two side edges where the partition board is connected with the housing plate in an inwardly concave manner .The cable integrated device can realize standard insertion; the cable connecting is high in reliability and good in consistency; and the matching is convenient, the exchangeability is strong and the standard is unified.

The invention discloses a partitioned array and SADA matching optimizing method reducing a pressure difference between rings and belongs to the technical field of communication satellites. The methodincludes the following steps that: south and north sun wing partitioned arrays are divided; the one-to-one correspondence relationship of the south and north sun wing partitioned arrays and a PCU shunt level are built; due to the one-to-one correspondence relationship of the south and north sun wing partitioned arrays and the PCU shunt level in step (2), the matching relationship between the southand north sun wing partitioned arrays and SADA power rings on a south and north sun wing sailboard driving mechanism is built, and the number of gaps in the SADA power rings is controlled to be minimum; and each gap is a potential difference, being not zero, between every two adjacent power rings, and therefore the number of 100 V pressure difference gaps of an SADA sliding ring is minimum, and the power supply safety risk caused by the pressure difference between the rings is lowered.

The invention discloses a desulfurization device parameter evaluation method based on online data, which comprises the following specific steps: 1, classifying basic indexes and completing a parameter-level evaluation unit; 2, establishing a mathematical model for the basic indexes and analyzing the mathematical model; 3, installing a data detection collector and setting an evaluation range; 4, determining an evaluation index allowable fluctuation range and an alarm limit value; 5, determining an evaluation rule and carrying out evaluation feedback on different working conditions; and 6, performing real-time data collection and evaluation control on the economy. According to the invention, through combined arrangement of field data acquisition and an online data platform, monitoring and early warning of desulfurization system operation with less manpower or even without manpower can be satisfied; through independent evaluation, overall and local dual control is facilitated; and throughmodeling processing, threshold division of data values and different scoring rules, distinctive evaluation is facilitated, and the applicability and applicability of actual construction are improved.

The invention discloses a real-time evaluation system for the operation performance and economy of a desulfurization device and an application method. The real-time evaluation system comprises an operation performance evaluation module and an economy evaluation module, the operation performance evaluation module and the economy evaluation module are both composed of parameter units, and the parameter units are composed of desulfurization device operation performance parameters and design economy parameters. The desulfurization device is divided into different modules so that classified controland maintenance are facilitated; monitoring and early warning can be carried out in real time through modular integration, computer online control early warning and other measures; through modeling processing of the parameter units, threshold division of data values and scoring rules under different working conditions, distinctiveness evaluation is facilitated, and applicability and applicabilityare improved; by evaluating the economy of the desulfurization device, the optimal setting can be performed under the normal operation of the desulfurization device, thereby being beneficial to saving the cost; and evaluation rules of economic evaluation are also established on the parameter units so that unified data processing and design are facilitated.

PROBLEM TO BE SOLVED: To unify designs between a remote control and a body of a wiring apparatus, etc., without the need to separately provide a wall-mounted holder for storing the remote control. ŽSOLUTION: The wiring apparatus includes a receiving portion 12 for receiving actuation signals, a wiring apparatus body 1 that operates in accordance with operation signals received by a light-receiving element for a remote control at the receiving portion 12, a transmitter for transmitting the operation signals by wireless in accordance with an operation unit and an operation for the operation unit, and a remote control 5 housed removably on the front face of the wiring fittings body 1. Ž

The invention relates to an optimization method for sub-array and SADA matching for reducing pressure difference between rings, which belongs to the technical field of communication satellites. The present invention comprises the steps of: dividing the north-south solar-wing sub-array; establishing the one-to-one correspondence relationship between the north-south solar-wing sub-array and the PCU distribution level; through (2) the one-to-one correspondence relationship between the north-south solar-wing sub-array and the PCU distribution level , establish the matching relationship between the south and north solar wing sub-arrays and the SADA power rings on the south and north solar wing sail drive mechanisms, and control the number of gaps in the SADA power rings to the minimum; the gap is between two adjacent power rings The potential difference is not zero, so that the number of 100V differential pressure gaps of the SADA slip ring is minimized, so as to reduce the risk of power supply safety caused by the differential voltage between the rings.

The invention relates to the field of overall layout design of a nuclear power plant, in particular to a method for arranging a main water supply corridor area of ​​a nuclear power plant. Including the main water supply corridor area set in the nuclear island electrical power plant, outside the nuclear island containment, and three loop main water supply pipelines that run through the nuclear island containment. Each loop main water supply pipeline is arranged with a main pipeline and a Bypass pipeline, the tail end of the main pipeline runs through the nuclear island containment through the penetrating piece, and the first safety NC level isolation valve, the first regulating valve, the first safety two stage isolation valve, main feedwater check valve; the top of the bypass pipeline is connected near the top of the main pipeline, and the tail end of the bypass pipeline is connected between the main feedwater check valve and the first safety secondary isolation valve of the main pipeline The position between; the second safety NC level isolation valve, the second regulating valve, and the second safety secondary isolation valve are arranged in sequence from the top to the end of the bypass pipeline. This method can reduce the overpressure of the nuclear island containment.

The invention discloses a special connector for SF6 equipment micro water test. The special connector for SF6 equipment micro water test is in a four-way valve type and comprises a pressure display end, a test instrument hose connector end, a check valve end and a device connection port end. The interior of the micro water test special connector is provided with a cavity. The top of the cavity is fixedly connected with the pressure display end. The bottom of the cavity is in threaded connection with the check valve end. The left side or the right side of the cavity is connected with the test instrument hose connector end, and the other side is connected with the device connection port end. The pressure display end is opposite to the check valve end. The test instrument hose connector end is opposite to the device connection port end. The universality of the special connector for SF6 equipment micro water test is achieved, gas pressure can be displayed, a check valve end can be rapidly turned off when a failure happens, and working efficiency and safety performance are improved.

The invention discloses multifunctional fitness equipment. The multifunctional fitness equipment comprises tension training positions and two chest expansion training positions arranged side by side,wherein a balance weight seat provided with a balance weight block is arranged behind each tension training position, the two chest expansion training positions can be separately used by one exerciserfor chest expansion training, and each person at the chest expansion training positions can carry out chest expansion training with different loads through respective balance weight seats behind; oneexerciser can carry out tension training on the corresponding tension training position, and all the balance weight seats serve as different load tension choices for one arm of the tension exerciser.After the structure above is adopted, the design is ingenious, the integral design is uniform, the integrated structural design occupies a small space, the overall manufacturing cost is low, the usedemands of a plurality of people of different training items in a narrow space are met, and the equipment reduces the expense for going to a fitness room for fitness and the time cost for going to thefitness room and back, adapts to the fast-paced living and fitness demands of people and has a wide application prospect.

The invention belongs to the technical field of precision gear testing, and discloses a reference-grade gear helix template. The invention provides a reference gear helical template which is easy to obtain high precision by generating processing method, and has an overall symmetrical structure. Slots, left-handed and right-handed gullets, axial datum toroid and radial datum cylinder, fine thread and center hole. Among them, the straight tooth groove includes one involute cylindrical surface on the opposite side of the 0° helix angle, the left-handed tooth groove includes one left-handed 15° and one left-handed 30° involute helical surface, and the right-handed tooth groove includes a right-handed 15° and a right-handed groove. Each of the 30° involute helical surfaces. The reference-grade gear helix template provided by the invention has unified design, processing and measurement datum, symmetrical structure, balanced quality, and base discs can be installed at both ends to facilitate the use of generating processing method to obtain high processing accuracy.

The invention relates to a limiting device for a high-temperature reheat steam pipeline and an arranging method of the limiting device. The limiting device comprises the high-temperature reheat steam pipeline and equipment connected to two ends of the high-temperature reheat steam pipeline; several axial limiters are arranged on the high-temperature reheat steam pipeline to offset thermal displacement at equipment interfaces by utilizing the thermal expansion property of the high-temperature reheat steam pipeline itself; the axial limiters are arranged near the parts, connected with the equipment, of the high-temperature reheat steam pipeline; the number of the axial limiters is 1 to 5 or the same number as that of the interfaces of the equipment connected with the high-temperature reheat steam pipeline; and the positions of the axial limiters are determined by the expression H=Z / (T*alpha)+L. The limiting device has the beneficial effects that universalization is realized; the problems of low laying efficiency and high investment are solved; the distribution computing difficulty of the limiting device is reduced; the mounting stability of the high-temperature reheat steam pipeline as well as the safety of equipment running can be improved; the design of supports and hangers of the high-temperature reheat steam pipeline is standardized and unified; and the application range is wide.

Rear structure of vehicles, a rear section of a tandem seat 22 is formed with a triangular form extending rearwards when viewing from the top. A rear grip 24 for a rear occupant arranged in at the rear of the tandem seat 22 is formed in a triangular form almost identical to the rear end of the tandem seat 22. As such, the sitting area is expanded with the rear section of the tandem seat being made into a triangular form extending rearward when viewing from the top to allow easy placing the commodity on the rear of the tandem seat. Furthermore, by forming the rear grip for a rear occupant arranged in at the rear of the tandem seat to be in a triangular form almost identical to the rear end of the tandem seat causes the two sides, that is, extensions of the rear grip of a triangular form to be located to the side of the rear occupant, to allow easy gripping. Furthermore, the rear section of the tandem seat provides an integral design sensation with the rear grip to improve the appearance characteristic of the body rear section.

The invention provides an input module of an intelligent terminal and the intelligent terminal provided with the input module. The input module is arranged on the intelligent terminal provided with afull screen. The input module comprises a pressing input unit and a fingerprint collection unit, wherein the pressing input unit comprises at least one thin film pressure sensor arranged in a screen projection region of the intelligent terminal and a first sampling circuit connected with the thin film pressure sensors; and the fingerprint collection unit comprises at least one fingerprint sensor arranged on a narrow plane between the screen of the intelligent terminal and the end edge of the intelligent terminal and at the same side as the screen and a second sampling circuit connected with the fingerprint sensors. By the adoption of the technical scheme, a main menu interface key function and a fingerprint recognition function are achieved at the same side of the screen; and unity of backdesign of the intelligent terminal is maintained, and a sense of beauty is obtained.

The invention discloses a continuous ion exchange device and a continuous ion exchange method for extracting gallium from Bayer mother solution. The device comprises resin, a resin column for loading the resin, a discharge main pipe communicated with the upper end of the resin column and a feeding main pipe communicated with the lower end of the resin column, wherein the resin column comprises atleast four resin column groups connected in series; the feeding main pipe comprises a Bayer mother solution feeding main pipe, a washing feeding main pipe, a flushing feeding main pipe and a transition feeding main pipe; the discharge main pipe comprises a Bayer mother solution discharge main pipe, a washing discharge main pipe, a flushing discharge main pipe and a transition discharge main pipe;each resin column group is provided with a feeding branch pipe communicated with the feeding main pipe and a discharge branch pipe communicated with the discharge main pipe; and each feeding branch pipe and each discharge branch pipe are provided with a control valve for cooperatively controlling the resin column groups to implement ion exchange, washing, flushing and resin transition processes in turn respectively. The method has the advantages of simple equipment, convenient operation and high automation degree.

The invention discloses an installation structure of an automobile back-row safety belt. The installation structure comprises an installation board. Four first screw holes are distributed in the rightsurface of the installation board in an arrayed mode, the middle portion of the right side face of the installation board is fixedly connected with a fixed board through screws, an emergency lockingretractor is arranged on the middle portion of the right side face of the fixed board, a pre-tightening device is arranged at the bottom of the emergency locking retractor, the inside of the emergencylocking retractor is fixedly connected with a braided belt, the braided belt is provided with a guide board, an insertion board and a decorative cover board, the braided belt penetrates through a groove below the guide board and a groove in the upper portion of the insertion board, a fixing sheet is arranged on the lower portion of the insertion board and provided with a groove, the lower surfaceof the insertion board is fixedly connected with an insertion buckle, and the lower surface of the insertion buckle is fixedly connected with a second fixing strip. By the adoption of the installation structure of the automobile back-row safety belt, the use safety of the safety belt is improved, the installation strength is improved, convenience is brought to installation and use, parts are under unified design, installation efficiency is improved, resource waste is reduced, and the comfort level is improved.

The invention discloses an evaluation system based on online desulfurization equipment and modules and an application method thereof. The evaluation system comprises an equipment-level evaluation unitand a module-level evaluation unit, the two evaluation units are independently integrated through basic indexes and are displayed and controlled through a computer, the computer is connected with data collectors installed at all positions of equipment, and the data collectors are arranged corresponding to the obtained basic index data in a one-to-one mode. During application, equipment and corresponding modules in the desulfurization device are respectively evaluated, so that targeted control is facilitated, and manpower and errors can be further reduced; through modeling processing of basicindexes, threshold division of data values and scoring rules under different working conditions, targeted evaluation of equipment and modules under various scenes is facilitated, and the applicabilityand applicability of actual construction are improved; and through real-time monitoring and early warning and economic evaluation, cost saving and unified data processing and design are facilitated.

The invention discloses a modern public traffic platform which comprises a base. The modern public traffic platform is characterized in that the base is provided with a waiting part; the two sides of the waiting part are provided with vehicle information display stations; one end of the base is provided with a lighting lamp; the waiting part comprises a shielding shed which comprises a base plate, two side plates and a top shed body; the top shed body comprises a fixing plate and a connecting plate which are connected front and back; the fixing plate is backwards obliquely arranged, and the connecting plate is forwards obliquely arranged; a water flowing trough is formed in the connecting position of the fixing plate and the connecting plate; the top of the connecting plate is downwards provided with a groove; a solar cell panel is embedded into the groove; the bottom of the connecting plate is provided with a first liquid crystal display screen which is internally provided with a GPS positioner; and the GPS positioner is connected with the first liquid crystal display screen.

The invention provides a PCB (printed Circuit Board) component and a manufacturing method thereof, belonging to the field of printed circuit boards. The method comprises the following steps of: creating a principle element symbol of a target component according to the target bonding pad and the target heat dissipation hole of the target component, wherein the principle element symbol comprises thefollowing components: a first pin corresponding to the target bonding pad and a second pin corresponding to the target heat dissipation hole; creating a physical packaging diagram of the target component according to the physical parameters of the target bonding pad and the physical parameters of the target heat dissipation hole, wherein the physical packaging diagram comprises a region of a first pin corresponding to physical parameters of the target bonding pad and a region of a second pin corresponding to the physical parameters of the target heat dissipation hole and arranged in the region of the first pin; manufacturing the PCB substrate of the target component according to the principle component symbol and the physical packaging diagram; and welding the target pin and the target bonding pad on the PCB substrate to obtain the PCB comprising the target component. The method can unify the specifications of the heat dissipation holes and is beneficial to heat dissipation of the PCBcomponents.

The invention discloses a modern public traffic platform which comprises a base. The modern public traffic platform is characterized in that the base is provided with a waiting part; the two sides of the waiting part are provided with vehicle information display stations; one end of the base is provided with a lighting lamp; the waiting part comprises a shielding shed which comprises a base plate, two side plates and a top shed body; the top shed body comprises a fixing plate and a connecting plate which are connected front and back; the fixing plate is backwards obliquely arranged, and the connecting plate is forwards obliquely arranged; a water flowing trough is formed in the connecting position of the fixing plate and the connecting plate; the top of the connecting plate is downwards provided with a groove; a solar cell panel is embedded into the groove; the bottom of the connecting plate is provided with a first liquid crystal display screen which is internally provided with a GPS positioner; and the GPS positioner is connected with the first liquid crystal display screen.

The invention discloses a server supporting multi-backboard cascading. The server includes a motherboard, which is provided with a BMC, a motherboard low-speed connector, an Expander chip, and multiple motherboard high-speed connectors. The BMC is connected to the motherboard low-speed connector through the I2C bus, and the BMC is connected to the Expander chip through the I2C bus. There are I2C repeaters, backplane low-speed connectors and backplane high-speed connectors respectively connected to the I2C repeaters on the backplane. Multiple backplane low-speed connectors are connected in series in sequence and then connected to the main board low-speed connector. The backplane corresponds to a motherboard high-speed connector, and each backplane high-speed connector is connected to the corresponding motherboard high-speed connector and then connected to the Expander chip; the BMC is configured to detect the in-position backplane and enable the I2C of any in-position backplane repeater, and use the backplane where the enabled I2C repeater is located as the gated backplane. The server of the invention solves the problem of repeated I2C addresses on cascaded backplanes, improves the polling efficiency of BMC access to backplane equipment, and reduces the load of the I2C bus.

The invention discloses a kind of logarithmic profile roller and a manufacturing method, comprising a roller main body, the roller generatrix of the roller main body is at the effective length L of the roller we Within the range, the roller body includes an arc one and an arc two, and the radius of the arc one is R 1 , the radius of the second arc is R 2 . This type of logarithmic profile roller, its logarithmic profile is only composed of two arcs, and the two arcs have different proportions in the roller length (calculated). Curve fitting based on geometry makes the calculation more convenient. Simple, two arcs make processing and inspection more convenient and fast, and can realize the unity of design, processing, inspection and application in a true sense, because the similar logarithmic curve makes the line contact rolling bearing, there will be no internal edge stress concentration in application , to avoid early failures.