383 results about "Helix angle" patented technology

The invention discloses a radial forging machine chuck rotation oscillation braking electro-hydraulic control system and method, and the control system comprises a position detection encoder installed on a hammer head of a forging main machine, a hydraulic servo motion controller, a high-frequency servo valve, an oscillation braking oil cylinder with the same area as an A cavity and a B cavity, and an oscillation braking device with a worm gear and a worm. The pressure sensor and the displacement sensor are integrated on the oil cylinder to form a closed-loop control loop; the control method comprises the following steps: activating an oscillation braking function and collecting hammer phase, oil cylinder pressure and displacement signals in real time; a sine control signal synchronous with the forging frequency is generated based on the brake phase of 270-360 degrees; a brake oil cylinder is driven to push the worm to axially move, and the rotating speed of the chuck is modulated through the helix angle characteristic; and the amplitude is dynamically adjusted through a displacement-pressure feedback signal, and 25MPa overrun protection is executed. The purposes of reducing the brake response delay rate, the forge piece distortion rate and the equipment impact load are achieved, and 90-620 times / min wide-frequency-domain forging is supported.

The utility model relates to the technical field of shell-and-tube heat exchangers, and particularly discloses a multi-pipe-diameter multi-helix-angle multi-strand winding pipe type heat exchanger. Comprising a shell, a middle core cylinder installed in the shell and a spiral assembly spirally wound on the outer side of the middle core cylinder in the axial direction of the middle core cylinder. The spiral assembly comprises a plurality of spiral winding tube bundle layers which are spirally wound on the outer side of the middle core cylinder in sequence; each spiral winding tube bundle layer comprises a plurality of groups of spiral winding tubes wound on the outer side of the middle core cylinder, and the outer diameters of the spiral winding tubes in each spiral winding tube bundle layer are arranged at equal intervals; one or more fluid media are arranged in the spiral winding pipes on the same layer, and one or more wall thicknesses of the spiral winding pipes are arranged and correspond to the fluid media in a one-to-one mode. The heat exchange requirement and the winding strength requirement can be effectively met, meanwhile, the use efficiency of the material can be improved, and the production and processing cost can be reduced.

The invention discloses a reverse type annular tooth groove planetary roller screw which comprises a nut, a screw rod, a plurality of rollers and a retainer, a multi-head internal thread is arranged in the nut, the rollers and the screw rod are both of an annular tooth groove structure without a helix angle, and the annular tooth grooves of the rollers are meshed with the internal thread of the nut and the annular tooth grooves of the screw rod respectively; first gears are machined at the two ends of the annular tooth groove of the lead screw, second gears are machined at the two ends of the annular tooth groove of the roller, and the first gears are meshed with the multiple second gears at the same time. The retainer is of an integral flexible retainer structure, and the pin rollers have the self-adaptive capacity in multiple directions in the circumferential direction and the radial direction through the retainer. And an arc-shaped roller path is designed on the screw rod and is matched with the ball spline housing to play a linear rolling guiding and rotation stopping role on the screw rod. The reverse lead screw has the advantages of being large in transmission ratio, compact in structure, easy to machine and assemble, low in cost, good in self-adaptive performance, high in positioning precision, good in reliability and the like.

The invention discloses stranding equipment for wire and cable production and manufacturing and a use method thereof, and relates to the technical field of cable production. The movable abutting plate is provided with a spherical surface used for limiting the twisting position of the outer stranded wire. According to the stranding equipment for wire and cable production and manufacturing, outer stranded wires are extruded in the stranded wire conveying direction through the movable abutting plates, so that the lead angles of the outer stranded wires are reduced, in the winding process of multiple strands of outer stranded wires, each strand of outer stranded wires is subjected to forward thrust of a spherical surface when being wound for one circle, and the outer stranded wires are not prone to falling off when being wound. When the friction force is too small, the thrust is transmitted forwards by the rear circle, so that the front spiral circle slightly moves forwards under the thrust force, the distance that the outer stranded wire slides backwards relative to the inner stranded wire due to too small friction force is compensated, and the strand scattering problem caused by relative sliding is reduced. And the inner and outer stranded wires are blown through the air supply unit, so that dust on the sheath is reduced, and the friction force between the inner stranded wire and the outer stranded wire is prevented from being reduced.

The invention relates to a milling burr (1) for an electrically or pneumatically operated hand-held tool for deburring, shaping, grinding and finishing iron-free surfaces, comprising: - a shank portion (2) and - a milling portion (4) made of a hard metal, in particular tungsten carbide, which adjoins the shank portion (2) and ends in a milling tip (6), wherein the milling portion (4) has a milling length (f) and a plurality of cutting edges (10) which are separated by mutually spaced main flutes (14) which have a main flute depth (h) and extend helically in a first twist direction (16) with a first twist angle (α) along the milling length (f), wherein each of the cutting edges (10) has a rake face (20) and a relief face (24) and a cutting edge (12) at the transition of rake face (20) and relief face (24), forming a rake angle (γ) and a relief angle (δ). The milling burr (1) according to the invention is characterized in that said relief face (24) is a first relief face (24) and said relief angle (δ) is a first relief angle (δ), wherein the first relief face (24) is adjoined in the circumferential direction of the milling portion (4) by a second relief face (26) which extends at a second relief angle (ε), and, in the region of the milling portion (4) with the largest diameter, the first relief angle (δ) is in the range from 6° to 20° and the second relief angle (ε) is in the range from 8° to 30°, and the second relief angle (ε) is greater than the first relief angle (δ). The invention also relates to the use of such a milling burr (1).

The invention relates to a multi-station cold heading forming process for a special-shaped pipe fitting of an automobile shock absorber, and belongs to the technical field of cold heading of special-shaped pipe fittings of automobiles. A combined female die with a three-stage gradual-change fillet structure is adopted, and the diameters of fillets are gradually increased to be matched with a gradient stiffness belleville spring buffer unit, so that staging release of stress is realized; a cross section sudden change stress peak value of the root of the flange is eliminated, the crack risk is reduced, a special-shaped punch of a 45-degree helical angle gradually-shrinking type flow guide groove is designed, axial and radial flow of materials is dynamically guided, meanwhile, the filling amount is controlled in real time through a hydraulic adjustable limiting mechanism, and the problems of folding and wall thickness fluctuation are radically solved; three sets of gradient clamping force clamping jaws distributed at 120 degrees and V-shaped pre-indentations are arranged, asymmetric deformation generated by preorder cold heading is compensated in a self-adaptive mode, and the coaxiality error of a special-shaped contour and a flange is reduced. The problems that in the multi-station cold heading process in the prior art, cracks are caused due to stress concentration of a fixed fillet die, and folding defects are caused due to out-of-control flowing of a linear flow guide groove material are solved.

The invention relates to the field of cable cabling, in particular to density-adjustable cabling equipment and a control method thereof.The cabling equipment comprises a feeding mechanism, a pre-deformation mechanism, a bundling mechanism and a control unit; the feeding mechanism comprises a first guide disc driven by a driving unit to rotate, a main unwinding wheel used for unwinding a main wire core and a plurality of auxiliary unwinding wheels used for unwinding stranded cables. The pre-deformation mechanism comprises a pre-deformation device, and the pre-deformation device is provided with a first diameter measuring unit and a second diameter measuring unit; the bundling mechanism comprises a box body and a pulling piece, the distance between the box body and the pre-deformation mechanism is adjustable, a cabling through hole for a main cable core to penetrate through is formed, and the control unit can calculate a target spiral angle of the stranded cable under the condition that the preset distance is met, and further calculates the rotating speed of the first driving unit and the pulling speed of the pulling piece; according to the invention, the cabling process can be accurately controlled, the cable coating density can be flexibly adjusted, the cabling quality can be guaranteed, and the production reliability can be improved.

The invention relates to the technical field related to intelligent production control, in particular to a powder spraying method and system for the surface of a slender pipe and a medium, and the method comprises the steps that the preprocessed slender pipe is placed on a workbench containing multiple assemblies, electrostatic spraying is conducted through a spray gun, powder feeding adjustment is conducted, the angle of a flow guide groove is dynamically adjusted according to parameter combination, and spraying uniformity is controlled in combination with rotating speed induction. The technical problems that dynamic parameter matching mechanisms for different pipe diameters and wall thicknesses are lacked, airflow changes in the inner space of a slender pipe are difficult to cope with, and uneven distribution of powder in the pipe is likely to be caused are solved, the coating thickness deviation is controlled by associating a spray gun mechanism with a pipe rotating assembly, and the spiral angle of a flow guide groove is dynamically adjusted along with friction torque; and the piezoelectric centrifugal switch is used for detecting the rotating speed fluctuation in real time, the spray gun displacement compensation and the powder feeding amount adjustment are automatically triggered to enable the powder to be distributed in the pipe, and the machining efficiency is improved on the basis that the powder spraying quality of the surface of the long and thin pipe is guaranteed.

The invention relates to a gear machining process, in particular to a design method for the output length of a variable-pressure-angle hob, and mainly solves the technical problem that the output length of the hob cannot be accurately controlled in an existing method. The method comprises the following steps that 1, according to the generating machining principle, the circumferential length needed by a variable pressure angle hob for hobbing a complete tooth width of a to-be-machined gear is calculated; (2) based on the circumferential length obtained in the step (1), in combination with the helix angle of the variable-pressure-angle hob and the helix angle of the gear to be machined, the axial length of the variable-pressure-angle hob for hobbing a complete tooth width is obtained through calculation; and (3) according to the axial length obtained through calculation in the step (2), in combination with the axial feed amount during hobbing, the cutter output length of the variable-pressure-angle hobbing cutter during hobbing is obtained through calculation. On the basis of the method, the cutter output length of the variable-pressure-angle hob can be accurately controlled, the risk of machining interference of the variable-pressure-angle hob is fundamentally avoided, and then high-precision machining of the gear is achieved.

An anti-bouncing-sticking high-stability drill bit for drilling. The drill bit comprises: a drill bit body (1), cutting teeth (3), gauge teeth (4) and a plurality of blades (20), wherein the blades (20) are arranged on the drill bit body (1); each of the blades (20) has a main cutting portion and a gauge portion distributed in a direction from the center of the drill bit to the outside; the cutting teeth (3) are mounted on the main cutting portions; and the gauge teeth (4) are mounted on the gauge portions. The plurality of blades (20) comprise at least two helical blades (2); and in the helical blades (2), a helix angle β is formed between a line connecting a gauge point (51) of the main cutting portion to a gauge end point (61) of the gauge portion and a plane perpendicular to the axis of the drill bit, and satisfies 15°≤β≤60°. The technical problems of poor borehole trajectory quality and difficulty in ensuring wellbore wall quality which are caused by poor stability of the drill bit during the drilling process of the drill bit are solved.

The invention provides a differential roller screw transmission assembly, which comprises a nut, a screw, a plurality of rollers and a retainer group, the nut is provided with an inner hole penetrating in the axial direction, and an annular tooth section is arranged on the inner circumferential face. The threaded rod is arranged in the inner hole in a penetrating mode, a thread structure is arranged on the peripheral face of the threaded rod, the thread structure is provided with M thread lines, and M is an integer larger than one. The plurality of rollers are arranged between the nut and the screw. Each roller has a uniform pitch diameter, the periphery of each roller is provided with an annular tooth groove structure with a plurality of tooth grooves, and the annular tooth groove structures are meshed with the thread structure of the screw rod and the annular tooth section of the nut. The number of the plurality of rollers is N, and N is a factor greater than one of M. The retainer group is arranged at two ends of the roller. And the spiral angle of each thread line of the screw is matched with the circumferential distance of the plurality of rollers, so that the axial distance between any thread line and the corresponding tooth groove between the two adjacent rollers is equal to the pitch of the annular tooth groove structure. Therefore, the part design and the manufacturing process are simplified, and the load sharing effect is improved.

A photosensitive member unit detachably mountable to a main assembly of an image forming apparatus, the image forming apparatus including a first main assembly side helical gear portion and a second main assembly side helical gear portion which are coaxially rotatable, the photosensitive member unit includes a photosensitive member rotatable about a rotational axis thereof; a first unit side helical gear portion for meshing engagement with the first main assembly side helical gear portion; and a second unit side helical gear portion for meshing engagement with the second main assembly side helical gear portion, wherein a twisting direction of a tooth of the second unit side helical gear portion is the same as the twisting direction of a tooth of first unit side helical gear portion, wherein a helix angle of the tooth of the second unit side helical gear portion is larger than a helix angle of the tooth of the first unit side helical gear portion, and wherein the first unit side helical gear portion and the second unit side helical gear portion are rotatable in a state in which the first unit side helical gear portion is in meshing engagement with the first main assembly side helical gear portion, and the second unit side helical gear portion is in meshing engagement with the second main assembly side helical gear portion.

The invention discloses a spiral chute capable of reducing the sintering return ore rate, and belongs to the technical field of sintered ore, the spiral chute comprises a spiral chute body, and a baffle is arranged on a chute bottom plate of the spiral chute body; the total mileage of the spiral chute is L, the radius of the spiral chute is R, and the spiral angle is theta; the three meet the following relation: L = 2piR * [1 + sin (theta-15)]; the height of the baffle is h, and the width of the chute bottom plate is l; the relationship between the two is # imgabs0 #, a is a constant, and the value range of a is 2-10. According to the method, the constraint relation among the total mileage of the spiral chute, the radius of the spiral chute and the spiral angle is constructed; the height of the baffle and the width of the chute bottom plate are restrained; according to the spiral chute designed based on the two constraint relations, the purpose of better reducing the sintering return ore rate can be achieved.

The rotary air cylinder comprises a cylinder barrel, a front cover and a rear cover, the front cover and the rear cover are arranged at the two ends of the cylinder barrel respectively, a piston and a piston rod are arranged in the cylinder barrel, the piston and the piston rod are matched to form a limiting structure, and the limiting structure is used for limiting the rotation angle of the piston rod relative to the cylinder barrel. The limiting structure further limits the axial stroke of the piston moving towards the front cover in the cylinder barrel into a first stroke and a second stroke, the limiting structure comprises a stroke adjusting piece arranged on the piston and / or the piston rod, and the stroke adjusting piece is used for adjusting the length of the first stroke. The length of the first stroke of the piston can be adjusted through the stroke adjusting piece, and then the rotation angle of the piston rod can be adjusted. In the actual production process, air cylinders with different rotation angles can be conveniently produced without changing the spiral angle of the spiral groove of the piston rod, the production cost is saved, and the production efficiency is improved.

The invention relates to a reverse toothless planetary roller screw, and belongs to the technical field of roller screws, the reverse toothless planetary roller screw comprises a screw rod, a long nut, a planet carrier assembly and a plurality of rollers, and the periphery of the screw rod is sequentially provided with a front shaft section, an external thread section and a rear shaft section; internal threads are arranged on the inner wall of the nut; each roller comprises a threaded part in the middle and polished shaft parts at the two ends; the thread part of the roller and the external thread section of the lead screw are opposite in rotation direction and equal in lead angle; the planet carrier assembly comprises a middle retainer, and the middle retainer is provided with at least three open grooves used for assembling the pin rollers in the radial direction. By canceling a screw rod gear / ring groove and pin roller gear / ring groove structure and combining a double matching mechanism of the planet carrier assembly, the machining bottleneck of a composite structure is thoroughly eliminated, the axial parallelism and the constant lead characteristic of the pin rollers are guaranteed, meanwhile, vibration noise is remarkably reduced, and high-precision and large-scale mass production is achieved.

An improved compound planetary gear system. In embodiments, a compound planetary gear system includes at least one planet pinion including a main shaft having a first gear for meshing with a sun gear and a second gear for meshing with a ring gear, and a carrier for supporting the at least one planet pinion. Teeth of the first gear are configured with a first helical angle with respect to a longitudinal angle of the at least one planet pinion, teeth of the second gear are configured with a second helical angle with respect to the longitudinal angle of the at least one planet pinion, the first helical angle different from the second helical angle.

The utility model belongs to the technical field of hinges, and particularly relates to a three-dimensional adjustable hinge which comprises a first hinge piece and a second hinge piece, a sleeve and an assembly column are fixedly arranged on the side edge of the first hinge piece and the side edge of the second hinge piece respectively, and a worm gear is rotationally arranged at the bottom end of the interior of the sleeve through a bearing. A screw is fixedly arranged at the top end of the worm gear, a worm is rotationally arranged at the position, close to the worm gear, of the inner wall of the assembly column in a penetrating mode through a bearing, teeth of the worm are meshed with teeth of the worm gear, and the helical angle of the worm 7 is smaller than the equivalent friction angle of a worm transmission system. A movable seat is rotationally arranged at the thread position of the screw rod through threaded connection, a top pipe is fixedly arranged at the top end of the movable seat, an insertion rod is fixedly arranged at the bottom end of the assembly column, and through cooperation between the worm and gear structures, height adjustment is more convenient; and the door body can be prevented from sliding down after the height of the door body is adjusted due to the self-locking characteristic of transmission of the worm and gear structure.

The invention provides a design method of a full-life diamond roller for a powerful inner honing wheel. The design method comprises the steps that design parameters of the diamond roller are determined according to parameters of an outer gear and the inner honing wheel; the design parameters of the diamond roller comprise a normal modulus Mn, a circle dividing normal pressure angle Afn, a helix angle Bf2, a tooth number Z2, a displacement coefficient Xn2, an addendum circle diameter Deg2, a root circle diameter Dig2 and an effective starting circle diameter dyx2; and calculating the addendum circle diameter and addendum width of the diamond roller. According to the parameters of the new inner honing wheel and the old inner honing wheel, design parameters of the two sets of diamond rollers are determined respectively, and then the design parameters of the full-life diamond roller are obtained through intersection; the tooth crest width of the diamond roller is checked, it is guaranteed that the tooth crest does not become sharp, parameters of the diamond roller are optimized, the optimality of the honing process is guaranteed, the diamond roller is designed only in 20 minutes at present, and compared with dozens of hours in the prior art, efficiency is greatly improved, and the new product development period is shortened.

The invention provides a lemniscate-shaped annular milling cutter and a design method, and relates to the technical field of milling cutter design, the lemniscate-shaped annular milling cutter comprises a cutter head part and a cutter handle part, the cutter head part is composed of an end edge part and a circumferential edge part, and the end edge part rotates by adopting a rotation generatrix composed of a Bernoulli lemniscate boundary curve and a transition arc to form a lemniscate ring surface; a spiral cutting edge is generated through an equal-spiral-angle edge line model, so that uniform distribution of cutting force and smooth chip removal are ensured; and the circumferential blade part intersects with the equal-helix-angle blade line through the cylindrical surface to form a spiral cutting edge. According to the design, cutting vibration is reduced through the variable curvature characteristic of the lemniscate, cutting force distribution is optimized, and meanwhile the chip removal capacity is improved by combining the equal helix angle design.

Drilling bits for removing material from a formation are provided. One such bit includes a bit body including a first gauge pad and a second gauge pad. The bit further includes a first blade including a leading portion and a trailing portion, where the leading portion is disposed on the first gauge pad with a negative helix angle and the trailing portion is disposed on the second gauge pad with a positive helix angle.

This application discloses a method for interference-free honing of a double helical gear using two honing wheels, relating to the field of gear machining technology. The method includes the following steps: Step 1: Establishing a constraint relationship between the shaft intersection angle of the honing gear and the width of the empty groove of the double helical gear, determining the interference-free honing shaft intersection angle, and optimizing the empty groove width; Step 2: Calculating the axial installation distance between the left and right honing wheels based on the structural parameters and shaft intersection angle of the double helical gear, determining the helix angle parameters of the left and right honing wheels, and establishing tooth surface models of the left and right honing wheels by enveloping the tooth surface of the double helical gear; Step 3: Preparing the left and right honing wheels based on the tooth surface models, assembling the left and right honing wheels according to the axial installation distance, and controlling the two honing wheels to perform interference-free honing of the double helical gear tooth surface at a fixed shaft intersection angle. This application can obtain a double helical gear with high surface quality and low noise characteristics through the honing process.

The invention belongs to the technical field of flow meters, and particularly relates to an intelligent precession vortex flow meter which comprises a measuring pipe body, connecting flanges are connected to the left end and the right end of the measuring pipe body, and a swirler assembly is arranged at an inlet of the measuring pipe body. When the intelligent precession vortex flowmeter is used for detecting the fluid with the low flow speed, the Venturi throat hole of the intelligent precession vortex flowmeter is reduced, the local flow speed of the fluid can be effectively increased under the working condition of the fluid with the low flow speed, the vortex generation strength and stability are enhanced, and the signal amplitude and the signal-to-noise ratio are increased; therefore, the measuring sensitivity, the linearity and the lower limit measuring capacity of the flowmeter in a low-flow-speed area are improved, the applicable flow range is expanded, the flow resistance of fluid in the rotation starting stage can be remarkably reduced by changing the spiral angle of the rotation starting device and reducing the using number of the rotation starting blades, and the rotation strength and the precession stability of the fluid at the low flow speed are enhanced.

The invention provides a hob and tunneling equipment, and belongs to the field of tunnel construction. The hob comprises a hob shaft and an end cover arranged on the hob shaft in a sleeving mode and used for pressing a bearing in the axial direction, the hob shaft is provided with a locking structure used for locking the end cover, the locking structure comprises a pressure-bearing face arranged on the end cover or a pressing ring and further comprises a sliding block and a pressing block which are assembled between the pressure-bearing face and the hob shaft in an interference mode, a spiral groove is formed in the peripheral face of the hob shaft, and the sliding block and the pressing block are arranged in the spiral groove. The sliding block comprises a base body and a matching protrusion embedded in the spiral groove, and the spiral angle of the spiral groove meets the requirement that the matching protrusion and the inner side wall face of the spiral groove can be self-locked in the axial direction. The tunneling equipment comprises the hob. According to the hob, the end cover is locked through matching of the matching protrusion on the sliding block and the spiral groove in the hob shaft, compared with a thread structure, the matching protrusion and the spiral groove are higher in strength and not prone to damage, and efficient and low-cost maintenance of the hob is facilitated.

The invention relates to a planetary gearbox (10) for a force-feedback unit of a steering wheel actuator for a steer-by-wire steering system of a motor vehicle, the planetary gearbox comprising: a ring gear (HR) and a sun gear (SO) arranged concentrically to the ring gear (HR); a plurality of planetary gears (PL) meshing with the sun gear (SO) and the ring gear (HR), wherein a toothing of the ring gear (HR) has a first helix angle (βHR) and a toothing of the sun gear (SO) has a second helix angle (βSO), and wherein a toothing of at least one of the plurality of planetary gears (PL) has a third helix angle (βPL) which differs from the first helix angle (βHR) and the second helix angle (βSO). The invention also relates to a steering wheel actuator for a steer-by-wire steering system of a motor vehicle.

The invention relates to a standard toothless planetary roller screw, and belongs to the technical field of roller screws, the standard toothless planetary roller screw comprises a screw rod, a nut, a planet carrier assembly and a plurality of rollers, and the periphery of the screw rod is provided with external threads; internal threads are arranged on the inner wall of the nut, and unthreaded hole parts are arranged at the two ends of the internal threads; each roller comprises a threaded part in the middle and polished shaft parts at the two ends; the thread part of the roller and the internal thread of the nut have the same screwing direction and the same lead angle; the planet carrier assembly comprises a middle retainer, and the middle retainer is provided with at least three open grooves used for assembling the pin rollers in the radial direction. By canceling nut gear ring / ring groove and pin roller gear / ring groove structures and combining a double matching mechanism of the planet carrier assembly, the machining bottleneck of a composite structure is thoroughly eliminated, the axial parallelism and the constant lead characteristic of the pin rollers are guaranteed, meanwhile, vibration noise is remarkably reduced, and high-precision and large-scale mass production is achieved.

The invention relates to the field of special tools for machining, in particular to a small-diameter large-lead-angle inner hole spiral groove turning tool and a design method thereof.The design method comprises the steps that S1, the pitch diameter, the lead angle and the spiral angle of a spiral groove are calculated according to the lead and the inner hole diameter of the inner hole spiral groove and the groove-shaped section diameter of the spiral groove; s2, according to the obtained lead angle and helical angle, simulating a tangent plane of an initial position when the turning tool machines a product, and determining angles of a front tool face and a rear tool face of the turning tool; s3, according to the profile size of the groove-shaped section of the spiral groove, the profile size of a turning tool cutting part matched with the spiral groove is designed; and S4, determining the diameter of a turning tool bar and the center height of the turning tool according to the diameter of the inner hole and a lathe machining mode.

The application provides a design and calculation method of main parameters of helical gear flowmeter, and belongs to the technical field of flowmeter. The design and calculation method is obtained by theoretically analyzing the helical gear flowmeter, and the influence of the number of gears, modulus, pressure angle, helix angle, radial clearance of the flowmeter and end face clearance of the flowmeter on the flow pulsation, clearance flow leakage and power loss of the helical gear flowmeter is discussed. In combination with the particle swarm optimization algorithm, two of the three performance indexes, flow pulsation, leakage and power loss, are changed into constraint conditions according to the design requirements, so that the multi-objective problem is changed into a single-objective problem for solving the main parameters of the helical gear flowmeter. Compared with the traditional method of calculating the displacement of the flowmeter through the empirical formula and the empirical coefficient, the application can improve the displacement design precision of the flowmeter, can clearly determine the influence degree of each parameter on the performance of the flowmeter, and can quickly solve the main parameters of the helical gear flowmeter through the optimization algorithm.

A rotary tool (1, 1a, 1b), comprising: a base (3) which has a rod shape and extends along an axis of rotation (X) from a first end (3a) to a second end (3b), where the base (3) a cutting part (5) arranged to have the first end (3a), a shaft part (7) which is arranged closer to one side of the second end (3b) than the cutting part (5), and a flow path (9) that is arranged within the base (3) and extends along the axis of rotation (X), the cutting part (5) has an outer perimeter area (11), a first cutting edge (13) which is arranged from the first end (3a) in the direction of the outer circumferential surface (11), a first groove (15) extending helically from the first cutting edge (13) towards one side of the second end (3b), and a first ridge line (17) formed by the first groove (15) and the outer circumferential surface (11), which is adjacent to the first groove (15) on a rear side in a direction of rotation (Y) of the axis of rotation (X), the flow path (9) a main flow path (19) extending from one side of the second end (3b) to one side of the first end (3a), and a first secondary flow path (21) extending from the main flow path (19) towards one side of the second end (3b), the first secondary flow path (21) has a first opening (23) which leads into the first groove (15), a first angle (Θ1) formed by the axis of rotation (X) and the first sideflow path (21) is smaller than a skew angle (Θ2) formed by the axis of rotation (X) and the first crest line (17), and the first angle (Θ1) is set to 0 degrees to 25 degrees

An apparatus for receiving a fluid stream therethrough comprises a body having an inlet end and an outlet end and defining a passage axially therethrough from the inlet end to the outlet end. The body comprises a first portion comprising first helical angle elements for inducing a first vortex flow component in the fluid stream, and a second portion comprising second helical angle elements for inducing a second vortex flow component in the fluid stream. The first helical angle elements have one of a left-handed or a right-handed orientation, and the second helical elements have the other of the left-handed or the right-handed orientation. The apparatus may be a tubing insert.

To provide a drive shaft for a vehicle capable of making right and left parts common while equalizing torsional rigidity on the right and left sides.SOLUTION: Any one of the outer circumferential surface spline teeth formed at both ends of the intermediate shaft and the inner circumferential surface spline teeth formed at the first joint and the second joint has a helix angle. The torsion angle is formed such that the inclination direction is opposite between the power source side and the drive wheel side. Accordingly, in a case where the vehicle drive shaft has common specifications on the left and right sides, the substantial axial length for transmitting power is likely to be equal on the left and right sides, and thus the torsional rigidity of the vehicle drive shaft is likely to be equal on the left and right sides. Therefore, in the vehicle drive shaft, it is possible to achieve commonality of components on the left and right sides while making the torsional rigidity equal on the left and right sides.SELECTED DRAWING: Figure 1