62results about How to "Uniform radial force" patented technology

A spring clutch is provided which has improved durability by preventing a clutch spring from breaking due to fatigue. A cylindrical clutch spring made from a wire having a square section is mounted between a pulley and a pulley hub mounted in the pulley. An end of the clutch spring is coupled to the pulley hub. A clutch surface is formed on the inner periphery of the pulley and is formed with a large-diameter recess at a position opposite to the end portion of the clutch spring including the torque transmission end. When the pulley rotates in one direction, the clutch spring expands. At this time, the end portion of the clutch spring including the torque transmission end expands in the large-diameter recess, thus relaxing sharp torque produced in the clutch. This prevents local stress concentration on the clutch spring and breakage of the clutch spring and improves the durability of the clutch.

An efficient positive displacement motor under a well comprises a bypass valve assembly, a falling prevention joint, a motor joint, a universal joint assembly and a bearing joint assembly. The efficient positive displacement motor under the well is simple in structure, convenient to use, stable in operation under the well, safe, reliable, high in complete machine efficiency, capable of outputting larger torque, long in working time and service life, suitable for drilling needs of various complex wells at the present, free of piercing leakage and high in working reliability. A streamlined flow channel enables water conservancy losses of a main flow channel to be reduced, turn-off force is large, the defects of the interference effect and tooth form distortion of the conjugation curvature of a traditional single-screw machine type positive displacement motor are overcome, a universal shaft operates flexibly, energy efficiency is high, the universal shaft can work in the environments where no sand grain exists, and drilling fluid erosion exists, the service life is long, and mechanism strength is high.

The invention relates to a rotating servo valve capable of realizing the continuously and steplessly adjustable flow rate, and belongs to the technical field of a hydraulic servo valve. The rotating servo valve is characterized in that the axial position of a valve core is regulated through rotating a spiral micrometer device connected with the valve core for changing the rated flow rate of the servo valve, four rectangular grooves are correspondingly formed in the valve core and a valve sleeve, and when the valve core and the valve sleeve relatively rotate, the rectangular grooves are mutually communicated or sealed for controlling the output flow rate, so the servo valve has the four-way function. The rotating servo valve has the effects and advantages that the valve core and the valve sleeve relatively rotate, the friction force is small, the anti-pollution capability is high, the zero-opening characteristics are realized, the dynamic performance is high, the structure is compact, the flow rate is high, the radial stress is balanced, and the manufacture difficulty is low.

The invention discloses an ultrahigh-pressure three-position four-way electromagnetic reversing valve and relates to the technical field of fluid pressure executing mechanisms. The ultrahigh-pressure three-position four-way electromagnetic reversing valve comprises a valve body, wherein a through hole is formed in the valve body; electromagnets are connected at two ends of the through hole; an oil distributing sliding sleeve is sleeved in the through hole; a first annular undercut groove, a second annular undercut groove and a third annular undercut groove are formed on the outer periphery of the oil distributing sliding sleeve; an oil inlet is formed on the second annular undercut groove; a first oil outlet is formed on the first annular undercut groove; a second oil outlet is formed on the third annular undercut groove; a valve core is arranged in the oil distributing sliding sleeve; annular blocks matched with the first oil outlet and the second oil outlet are arranged in the length direction of the valve core; spring bases are arranged in the through hole and between the two ends of the oil distributing sliding sleeve and the two electromagnets; each spring base is provided with an inner base body and an outer base body; and a spring is connected and a push rod is arranged between each group of the inner base body and the outer base body. A slide valve structure is easy to reverse under high pressure.

The invention discloses a dentiform sphere shaped heavy oil hydrotreated catalyst and a preparation method thereof. The catalyst comprises an active composition, an addition agent and a dentiform sphere shaped aluminum oxide carrier, wherein the active composition comprises compounds of cobalt and nickel, and a compound of molybdenum or / and tungsten; the addition agent comprises a compound of phosphor, silicon, boron or halogen or compounds of any two compositions of the phosphor, the silicon, the boron and the halogen; and compositions according to gross weight of the dentiform sphere shapedheavy oil hydrotreated catalyst comprise: 2 to 6 percent of the cobalt compound, 3 to 10 percent of the nickel compound, 0 to 26 percent of the molybdenum compound, 0 to 8 percent of the tungsten compound, and 0.5 to 2 percent of the addition agent. The catalyst has the characteristics of high specific surface area, large pore volume, high strength, proper surface acid content, small bed pressuredrop, low reaction temperature and high activity of hydrodesulfurization and denitrification. The preparation method comprises preparation of a precursor substance of the aluminum oxide carrier, preparation of the dentiform sphere shaped aluminum oxide carrier, preparation of a catalyst steeping fluid and preparation of the catalyst. The preparation process can be mastered and realized simply andeasily.

The invention discloses a composite sealing device applied to a piston of a hydraulic cylinder, and the hydraulic cylinder and belongs to the technical field of the hydraulic cylinders. The compositesealing device adopts a separated type piston and comprises at least two piston bodies, wherein a tiny radial clearance exists between the outer edge of a first piston body (2) and the inner wall of acylinder barrel (12) in order to form a first clearance seal; and the outer edge of a second piston body (6) is respectively provided with a sealing part (7), a first retainer ring (5) and a secondretainer ring (8) to form a sealing ring seal. The first piston body (2) and the second piston body (6) are integrally connected with each other through screw threads so as to form a composite piston.The composite piston is integrated with one sealing ring seal and at least one clearance seal in the axial direction so as to form a composite sealing structure. The composite sealing device disclosed by the invention simultaneously adopts the sealing ring seal and the clearance seal to prevent internal leakage, overcomes the shortcomings of the prior art when the sealing ring seal and the clearance seal are used independently, achieves a good sealing effect and is applicable to occasions of which the oil liquid pressure is large and the requirements on the sealing performance are high.

The invention discloses a seamless stent and a manufacturing method of the seamless stent; the seamless stent is used for being intervened in a blood vessel and is formed by weaving at least one weaving thread; each weaving thread has an even number of free ends, and the free ends of the weaving thread are in butt joint in pairs; after being wound by the weaving threads, the stent has a cylindrical structure; all the free ends of each weaving thread are respectively provided with a cutting part; the cutting parts of every two free ends which are in butt joint are spliced in a seamless way, so that a splicing part is formed, and the diameter of the splicing part is equal to that of the corresponding weaving thread; a connecting pipe sleeves outside each splicing part; the inner walls of the connecting pipes are connected with the outer walls of the splicing parts in a seamless way. According to the seamless stent, the splicing parts formed by the free ends of the weaving threads are connected with the connecting pipes in a seamless way; the free ends of the weaving threads are provided with the cutting parts, and the diameters of the splicing parts formed by splicing the free ends are equal to those of the weaving threads, so that the diameters of the splicing parts are reduced, and the radial force and the axial force of the free ends are evenly distributed; the contact area among the free ends are enlarged by the cutting parts of the free ends, so that laser welding is conveniently carried out; the seamless stent is good in flexibility and excellent in attractiveness.

The invention discloses a centrifugal water pump provided with two impellers. The water pump comprises a pump body (1); a water inlet (11) and a water outlet (12) are formed in two ends of the pump body (1); a water inlet partition (2) is arranged at the water inlet (11) to divide a water inlet channel into a first water inlet channel (21) and a second water inlet channel (22); a water outlet partition (3) is arranged at the water outlet (12) to divide a water outlet channel into a first water outlet channel (31) and a second water outlet channel (32); a motor assembly comprising a spindle (8) is arranged in the pump body (1); two ends of the spindle (8) are connected with a first impeller (41) and a second impeller (42); the first water inlet channel (21) and the second water inlet channel (22) are led into an inlet of the first impeller (41) and an inlet of the second impeller (42) from two sides of the pump body (1); and a liquid enters via the water inlet (11), enters the first impeller (41) and the second impeller (42) from two sides of the pump body (1) after being divided by the first water inlet channel (21) and the second water inlet channel (22), is collected in the first water outlet channel (31) and the second water outlet channel (32) after flowing out of the first impeller (41) and the second impeller (42) and flows out of the water outlet (12). The invention can be applied to the field of water pumps.

The present invention relates to rack contractor, and is especially a conic sleeve type cylindrical netted isodiametric rack contractor. The conic sleeve type cylindrical netted isodiametric rack contractor includes conic sleeve with N equant guide conic tracks with sector block each, and driving unit connected to the conic sleeve, and the N guide conic tracks constitute one frustum with one large end and one small end. One conic mechanism with only radial force on the contracted rack is designed based on the mechanical features of cylindrical netted rack structure so as to alter the diameter continuously at will for isodiametric rack contraction.

The invention discloses a phase-change energy storage device. The phase-change energy storage device comprises a heat conduction piston cavity, a phase-change unit, a heat conduction piston, a limiting ring, a first spring, a heat conduction cap and a heat sink; the piston cavity and the heat sink are oppositely arranged on the front surface and the rear surface, the heat sink is arranged in front of the piston cavity, the front end of the piston cavity is open, and the rear end of the piston cavity is sealed; the piston is in sliding fit in the piston cavity, and the piston is in dynamic sealing with the inner wall of the piston cavity; the phase-change unit is filled in a cavity defined by the end part of the rear end of the piston and the piston cavity, the limiting ring is fixedly connected with the inner wall of the front end of the piston cavity, and the first spring is arranged between the limiting ring and the piston; and the two ends of the first spring are respectively abutted against the limiting ring and the piston, the heat conduction cap is connected with the front end of the piston, the front end of the heat conduction cap penetrates out of the piston cavity, and the heat sink is arranged in front of the heat conduction cap. The phase-change energy storage device can dissipate heat generated by high-power equipment on the basis of keeping a small size, the problem of thermal control of the high-power equipment on a satellite is solved, and normal operation of the equipment is guaranteed.

The invention discloses a double-membrane back pressure valve. The double-membrane back pressure valve comprises a valve body, a bonnet, a valve rod, a force measuring sensor, a spring, membranes, a damper, a display unit and the like and is characterized in that the upper membrane and the lower membrane are separated through a metal support piece to form a middle cavity, the spring and the damperare fixed on the upper membrane through a bottom plate, the upstream position of the lower membrane is provided with a small hole. When the double-membrane back pressure valve is used, a hand wheel is rotated to allow the valve rod to move downwardly, and the valve is closed; when fluid pressure is larger than a set value, the membranes upwardly compress the spring, the back pressure valve is opened, and fluid start flowing; when the fluid pressure is smaller than a set value, the spring pushes the membranes downwardly to close the back pressure valve, and fluid flowing is stopped. The double-membrane back pressure valve has the advantages that by the small hole, the fluid pressure is transmitted into the cavity between the two membranes, the upper membrane is uniformly stressed, the stress of the membranes, the spring and the damper is relatively balanced, and valve movement stability is achieved; by the damper, gentle valve movement is achieved, and disturbance to the flowing is reduced.

The conic perforator includes frame, upper cover, base seat, two rotating drums inside the frame, two rollers installed separately on the two rotating drums, guide plate its regulator. The frame is one cylinder cast integrally with low expansion coefficient metal. The guide plate regulator is locked via inclined wedge on the frame. The distance between the guide plate and the central line is regulated via a motor driven horizontal screw elevating mechanism. The integral cylindrical frame of the conic perforator has less material consumption, strengthened rigidity, reasonable stress state and homogeneously distributed radial stress.

The invention discloses a SC-type optical fiber connector comprising a packaging housing, a sleeve seat, a first inserting core, a second inserting core, a tail handle, a balance spring, a bearing seat, a clamp screw nut, and a rubber sleeve pipe. The end part of the first inserting core is provided with a small diameter connecting part in an extended manner, and the corresponding end part of the second inserting core is provided with a connecting groove. The middle part of the first inserting core is connected with an elastic support, and the outermost edge of the elastic support abuts against the inner wall of the sleeve seat. The rear end outer wall of the sleeve seat is provided with an installation groove, in which is movably disposed a steel ball. The front end outer wall of the bearing seat is provided with an annular clamping groove. The inner wall of the packaging housing is provided with an annular avoiding groove cooperated with the steel ball, and the rear end of the sleeve seat is fixedly connected with a rear seat, and a reset spring is disposed between the rear seat and the packaging housing in an abutting manner. The middle part outer wall of the sleeve seat is provided with a large diameter part, and the packaging housing is movably disposed between the large diameter part and the rear seat. The SC-type optical fiber connector has advantages of simple and reasonable structure, convenient and fast installation, high optical coupling efficiency, stable working performance, and long service lifetime.

The invention discloses a slips mechanism for manufacturing a sand prevention screen pipe and a clamping method. The slips mechanism comprises a slips rack, wherein two parallelly arranged slide bars are arranged on the slips rack; a first slips plate and a second slips plate are sleeved on the slide bars; a first slips piece is connected onto the first slips plate; a second slips piece is connected onto the second slips plate; the second slips plate is connected with two parallelly arranged connecting rods; the other ends of the two connecting rods penetrate through the first slips plate and the slips rack so as to be connected with an air cylinder fixing plate; the air cylinder fixing plate is connected with the cylinder body of an air cylinder; and a piston rod of the air cylinder penetrates through the slips rack so as to be connected with the first slips plate. The slips mechanism for manufacturing the sand prevention screen pipe can be used for effectively clamping an objected to be clamped.

The invention provides a linkage compressing mechanism. The mechanism comprises input shafts, bearing pedestals, compressing devices, a limiting plate fixing device and a controller. The linkage compressing mechanism has the advantages of being simple in structure, reliable in action, low in cost and easy to expand. The compressing devices are symmetrically distributed on the input shafts at the two ends of a second bearing pedestal, loads are symmetric, radial stress is uniform, and steering and transmission are reliable. Through connection of the input shafts and the four compressing devices, the linkage compressing function is achieved, a complex control mechanism is not needed, the part number is reduced, the linkage compressing mechanism is small in size, distance sensors are arrangedon pressing plates, the input shafts are rotated, after the compressing devices carry out compressing action, the sensors send out feedback signals of making contact with the compressing parts, the controller drives the limiting plate fixing device to compress an angular limiting plate according to the feedback signals, position changes of the input shafts are prevented, and the function of compressing state locking is achieved.

The invention discloses a leak-free sleeve suspending device. The device comprises a sealing socket, sealing rings, a slip, and a slip seat which are connected by taking a sleeve as a shaft. The sealing socket is connected with the slip seat through a bolt; an inner conical hole of the slip seat is in taper fit with an outer wall of the slip; and tooth grooves are uniformly distributed on the inner wall of the slip to form a sleeve suspending slip limiting structure. A sealing structure into which the sealing rings are embedded is arranged in an inner hole, matched with the sleeve, of the sealing seat. In the leak-free sleeve suspending device, the slip consists of four to six equal tegular blocks; and a split slip is axially limited by a limit ring, and a radial screw hole installation screw which is uniformly distributed in the waist part of the slip seat locks the limit ring. During actual use, the bolt is adjusted, then the slip is accurately placed in the inner conical hole of the slip seat, radially applied force is uniform, and the wall of the suspended sleeve is not deformed, so that the sealing performance of the sealing structure at the upper end is not influenced. The sleeve is suspended reliably, and sealed strictly; and any resin implantation operation is not required during use, the safety performance of a product is greatly improved, and using cost is reduced directly. The leak-free sleeve suspending device is suitable for sleeves with different calibers.

The invention relates to the field of compressors, in particular to a two-stage air suspension centrifugal compressor capable of reducing radial force. The two-stage air suspension centrifugal compressor comprises a motor shell, a motor shaft, an air bearing device, a first volute, a first impeller, a second volute and a second impeller. Each volute body is provided with a partition tongue, a first spiral section, a second spiral section and a diffusion section, wherein the first spiral section starts from the partition tongue and ends at the intersecting line of the diameter of a volute base circle in the vertical direction and the volute body. Each partition plate is provided with a spiral section and a horizontal section, wherein the spiral section is the same as the corresponding first spiral section in shape and is in central symmetry with the corresponding first spiral section relative to the volute base circle, and the horizontal section is tangent to the spiral section and is distributed in the horizontal direction. According to the compressor, the partition plates are arranged in the volutes to divide volute chambers into the inner volute chambers and the outer volute chambers, and it is guaranteed that airflow at outlets of the volutes is stable; and the spiral sections which are the same as the first spiral sections in shape and is in central symmetry with the first spiral sections relative to the volute base circles are arranged on the partition plates, so that radial stress of the volutes is more uniform.

The invention provides a cylindrical rock test piece side surface grinding device and a using method thereof. The grinding device comprises bases, stabilizing supporting columns, clamping columns andgrinding rods, a motor and a limiting telescopic rod are arranged in the base, the stabilizing supporting columns support and fix the whole device, and the clamping columns are fixed between the basesand used for stably clamping a rock test piece, and the grinding rods are evenly arranged around the clamping columns and used for grinding the side face of the rock test piece; and the grinding method comprises the steps of clamping the rock test piece, installing the grinding rods, adjusting the position of the rock test piece, grinding the rock test piece and picking the rock test piece. According to the cylindrical rock test piece side face grinding device and the using method thereof, the rock test piece is not prone to being damaged, practicability and high efficiency are achieved, themanufacturing success rate is high, the rock test piece with the accurate diameter size and the smooth surface can be manufactured through one-time grinding, a foundation is laid for a laboratory rockmechanical test, and important significance is achieved for preventing and controlling mine disasters.

The invention discloses a symmetric ocean current power generation device with single impeller and a high length-diameter ratio. The device adopts a single-impeller symmetric structure; two sets of transmission and power generation systems are respectively arranged at two ends of an impeller hub; the transmission and power generation systems mainly consist of guide covers, and generators and transmission gear boxes mounted in the guide covers; the two sets of transmission and power generation systems are symmetrically distributed about the impeller hub; the impeller hub is connected with the transmission gear boxes by main shafts; output ends of the transmission gear boxes are connected with the generators; impeller blades are mounted on the peripheral surfaces; and output cables of the generators of the two sets of transmission and power generation systems are connected with synchronization or load devices by electric parallel balance output devices. The device optimizes the two-way flow field characteristics, realizes the power dividing, effectively reduces the specification performance requirements on the transmission and power generation systems under the same power, decreases the design and manufacturing costs, effectively improves the stress condition of a horizontal-axle ocean current power generation device, improves the operation stability, and prolongs the service life.

A conical piercing machine, comprising a frame, with an upper cover and a base on the upper part and the bottom of the frame respectively; two drums placed in the frame and two rollers respectively installed on the drums; The guide plate and its adjustment device, the frame is a cylindrical body with a circular cross-section integrally cast from low-expansion metal. The guide plate adjustment device of the tapered piercer is placed outside the frame as a whole, and is locked on the frame with a wedge. The distance of the guide plate relative to the center line is adjusted by means of a motor operated horizontally arranged screw jack. Because the tapered piercing machine of the present invention adopts the integral casting frame of the cylindrical structure, the casting material of the frame can be greatly saved, and the overall rigidity of the frame is enhanced, and the force during the perforation operation is more reasonable, especially the radial force is uniform, There are no stress concentration points.

The invention discloses a loop sleeve type elastic metamaterial structure with low-and-medium-frequency vibration reduction characteristics. According to the structure, a bottom surface is arranged on one side of a solid circular ring structure; a plurality of layers of circular rings are periodically arranged on the bottom surface along the radius direction of the solid circular ring structure from inside to outside; a trunk part is arranged in the innermost circular ring; four wedge-shaped blocks are arranged on the outer side of each layer of circular ring at intervals; the trunk part is connected with the wedge-shaped blocks on each layer of circular ring through four columnar structures to form a radial elastic structure; and the radial elastic structure extends outwards from the circular ring at the innermost layer and is connected with the side wall of the circular ring at the outermost layer to form the loop sleeve type elastic metamaterial structure with the low-and-medium-frequency vibration reduction characteristics. The radial elastic structure and the solid circular ring structure are connected to form a partially hollow structure, so excellent vibration reduction characteristics can be provided in low-and-medium-frequency environments.

The invention discloses an active piston phase modulation and power recovery integrated pulse tube refrigerator supported by a column spring. A shock absorber, an active phase modulation and piston power recovery mechanism, a compressor and a cold finger of the refrigerator are arranged on the same axis, and an active phase modulation piston shaft penetrates through an inner hole of a compression piston and is connected with a refrigerator shell through a phase modulation piston column spring. A compressor motor and an active phase modulation piston motor both adopt moving coil type linear motors, so that the radial vibration is small. The compression piston and the active phase modulation piston both adopt gas bearings, the compression piston is supported by a single-side column spring, and the active phase modulation piston is used for recovering expansion work and improving the efficiency of the refrigerator. Two displacement sensors are arranged to monitor the displacement of the active phase modulation piston and the displacement of the compression piston correspondingly, the phase between the compression piston and the active phase modulation piston is adjusted through the active phase modulation piston motor, and efficient operation of the refrigerator is guaranteed. The refrigerator has the advantages of compact structure, low vibration, work recovery and high refrigeration efficiency.

The invention relates to a rotating servo valve capable of realizing the continuously and steplessly adjustable flow rate, and belongs to the technical field of a hydraulic servo valve. The rotating servo valve is characterized in that the axial position of a valve core is regulated through rotating a spiral micrometer device connected with the valve core for changing the rated flow rate of the servo valve, four rectangular grooves are correspondingly formed in the valve core and a valve sleeve, and when the valve core and the valve sleeve relatively rotate, the rectangular grooves are mutually communicated or sealed for controlling the output flow rate, so the servo valve has the four-way function. The rotating servo valve has the effects and advantages that the valve core and the valve sleeve relatively rotate, the friction force is small, the anti-pollution capability is high, the zero-opening characteristics are realized, the dynamic performance is high, the structure is compact, the flow rate is high, the radial stress is balanced, and the manufacture difficulty is low.

The biomedical engineering device is provided with one main body with n guide tracks, n quadrant blocks, conjugated gears, control pin and other parts. The conjugated gears can rotate clockwise or counterclockwise to make the n quadrant blocks move synchronously and centripetally or centrifugally. The biomedical engineering device has also pallet, spring, distance ring, etc. The present invention has been applied practically.

The biomedical engineering device is provided with one main body with n guide tracks, n quadrant blocks, conjugated gears, control pin and other parts. The conjugated gears can rotate clockwise or counterclockwise to make the n quadrant blocks move synchronously and centripetally or centrifugally. The biomedical engineering device has also pallet, spring, distance ring, etc. The present invention has been applied practically.

The invention discloses an integral type bearing inner tube in a spinning ring spinning frame. The integral type bearing inner tube comprises a bearing block, an elastic tube, an oil preventing cap, a spindle bottom sheet, a spindle bottom mat and a lining, and is characterized in that a pin roller with a holder is clamped in the position, between the upper end of the elastic tube and the lower end of the oil preventing cap, of an inner hole of the bearing block. The inner wall of the bearing block, the upper end face of the elastic tube and the lower end of the oil preventing cap serve as an outer ring, a lower bearing plate and an upper bearing plate of the pin roller respectively to form an integral type bearing structure in a combined mode, the outer ring, the upper bearing plate and the lower bearing plate of a spindle bearing are eliminated, the requirement for the matching accuracy among parts is lowered, the concentricity of the bearing hole is guaranteed, the hole radial stress is even, and the service life of a spindle is prolonged; meanwhile, due to the fact that the outer diameter of the bearing block is reduced, the diameter of a wharve of the spindle is prompted to be reduced, high-speed operating of a smaller wharve can be adapted, and the operating speed is as high as 25000 r / min to 30000 r / min.

An efficient positive displacement motor under a well comprises a bypass valve assembly, a falling prevention joint, a motor joint, a universal joint assembly and a bearing joint assembly. The efficient positive displacement motor under the well is simple in structure, convenient to use, stable in operation under the well, safe, reliable, high in complete machine efficiency, capable of outputting larger torque, long in working time and service life, suitable for drilling needs of various complex wells at the present, free of piercing leakage and high in working reliability. A streamlined flow channel enables water conservancy losses of a main flow channel to be reduced, turn-off force is large, the defects of the interference effect and tooth form distortion of the conjugation curvature of a traditional single-screw machine type positive displacement motor are overcome, a universal shaft operates flexibly, energy efficiency is high, the universal shaft can work in the environments where no sand grain exists, and drilling fluid erosion exists, the service life is long, and mechanism strength is high.

The invention discloses a four-loosening-preventing and two-falling-preventing type power output shaft of a screw drill. The power output shaft comprises a main shaft 1, a bearing section housing 4 positioned at the outer side of the main shaft, and a centering device 8 positioned at the outer side of the bearing section housing; upper radial bearings 3, rolling bearing sets 7 and lower radial bearings 12 are arranged in the main shaft and the bearing section housing; the main shaft 1 is connected with a bearing housing 4 at the outer side of the main shaft through a housing locking nut 13; an upper locking nut 2 is arranged between the main shaft 1 and each upper radial bearing 3; the bearing section housing 4 is connected with the centering device 8 through a centering device nut 10; falling preventing locking nuts 11 and adjusting separating sleeves 9 are arranged between the rolling bearing sets 7, the main shaft 1 and the lower radial bearings 12.