38 results about "Angle alpha" patented technology

The invention relates to a method and device for designing a spatial streamline inlet of a rotational flow separator, and the method comprises the steps: determining an inlet angle alpha, a wrap angle beta, an incident angle gamma and an overturning angle theta of the inlet of the rotational flow separator according to the performance requirements of the rotational flow separator; the method comprises the following steps: selecting a control point at a rotational flow separator, generating a basic shape of a characteristic bus of the spatial streamline inlet through a spline curve equation, then selecting a type value point to carry out iterative optimization on the bus shape, and determining a final curve shape of the spatial streamline inlet through an entrance angle, a wrap angle, an incident angle and a flip angle; based on the inlet shape of the rotating flow separator, the section shape of a space streamline inlet is designed through a Bezier curve equation; and according to the final curve shape and the section shape of the spatial streamline inlet, the spatial streamline inlet structure of the rotating flow separator is determined. Compared with the prior art, pre-separation of particles / liquid drops is achieved through fluid inertia accelerated rotation, and the separation efficiency of the hydrocyclone is improved.

The application provides an internal embedded bomb cabin honeycomb configuration aerodynamic layout for improving flow field stability, and the internal embedded bomb cabin cross section body is a hexagonal honeycomb configuration layout, wherein the top surface of the honeycomb configuration is opened, the other five surfaces are closed wall surfaces, the top surface is parallel to the bottom surface, the included angle alpha between the bottom surface and the adjacent surface is 135 degrees, the longitudinal depth ratio beta of the honeycomb configuration is L / H=1.5, L is the maximum transverse distance of the bomb cabin cross section, and H is the maximum longitudinal height of the bomb cabin cross section. Under the condition of meeting the requirements of structural strength, sound and heat insulation, weight reduction, internal structure design of the fuselage, capacity and other constraints, the internal flow flow field stability of the internal embedded bomb cabin can be greatly improved, the flow field characteristics are improved from the physical root, the evolution of fine vortex and secondary vortex is effectively inhibited, and the process of the flow field from the steady state to the unsteady state is greatly delayed. Because the optimization design effectively inhibits the unsteady flow, especially the premature appearance of the turbulent flow, the aerodynamic efficiency of the internal flow of the bomb cabin is improved.

The application discloses a grinding processing method for inner concave outer circle and end face, which comprises the following steps: grinding the inner concave outer circle and end face of a part to be processed by using a grinding wheel; the grinding wheel comprises a grinding wheel body and a connecting rod; one end of the connecting rod is connected to a grinding wheel frame, and the other end is connected to one end of the grinding wheel body; a grinding surface is arranged on the side surface of the grinding wheel body to grind the part to be processed; the central axis of the connecting rod and the central axis of the part to be processed have an inclination angle alpha; on the plane passing through the central axis of the part to be processed, the end face projection line is used as a reference line, the highest height of the inner concave outer circle projection line relative to the reference line is H, the diameter of the grinding wheel body is D, the diameter of the connecting rod is d, the length of the connecting rod is l, l<=3d is satisfied, and beta=90-alpha. The application has the advantages of high machining precision and high efficiency.

The invention provides a radar covering part design method and system, a vehicle and an evaluation method. The radar covering part design method comprises the steps that three-dimensional models of a radar and a covering part are established; measuring a first included angle alpha between the radar and the covering part on the horizontal section and a second included angle beta between the radar and the covering part on the vertical section; the larger value in the first included angle alpha and the second included angle beta is called as an included angle theta between the radar and the covering part; and calculating the optimal thickness d of the covering part according to the included angle theta between the radar and the covering part, the electromagnetic wave frequency f of the radar and the dielectric constant of the covering part. The influence of the installation angle of the covering part and the radar on the optimal thickness of the covering part can be fully considered, so that the detection performance of the radar is ensured.

The application discloses a processing method of an adjustable-angle golf club pipe handle, which completes mechanical processing procedures of the pipe handle on a machine tool, and utilizes a first spindle and a second spindle to move along an X axis transversely, and utilizes a first tool seat and a second tool seat to flexibly move along the X axis and a Z axis to adjust the position of a workpiece and a tool, so that all mechanical processing is completed, the occupation of the machine tool is reduced, compared with traditional multiple intermediate sequences and manual clamping, the production cycle is reduced, and the processing efficiency is improved. An inner thread hole of the pipe handle and a center axis of an installation inner hole have an angle alpha, the rotation axis of the rotary tool is offset from the center axis of the pipe handle by adjusting the installation posture of a driving unit on the first tool disc, quick and flexible adjustment can be conducted according to production requirements, the production requirements of different products can be quickly adapted, and good convenience and applicability are achieved.

The invention discloses a method for correcting propeller deflection and a device for adjusting propeller deflection. The method comprises the steps that a propeller is installed to a set position; selecting a three-coordinate direction of a rectangular coordinate system of the measurement reference of the measurement device; measuring a first angle gamma at which the paddle deflects around an axis parallel to the first direction; measuring a second angle alpha at which the paddle deflects about an axis parallel to the second direction; measuring a third angle beta at which the paddle deflects about an axis parallel to the third direction; and adjusting the position of the paddle so that the first angle gamma reaches a first set value, the second angle alpha reaches a second set value, and the third angle beta reaches a third set value. According to the method for correcting the deflection of the paddle, the measuring device is in communication connection with the upper computer, the actual coordinates of the paddle in the selected three-coordinate direction are measured through the measuring device, the upper computer calculates and obtains the deflection angle of the paddle around the axis parallel to the three-coordinate direction, the deflection operation of the paddle can be completed by adjusting the angle to the set value, and the efficiency is high.

The invention discloses a vacuum coating device and a coating uniformity correction method. The vacuum coating device comprises a vacuum chamber, a first target material group, a second target material group and a base, the first target material group and the second target material group are arranged in the vacuum chamber; the base is rotatably arranged in the vacuum chamber around a first axis, and the first target group and the second target group are respectively arranged on two sides of the first axis; the workpiece is rotatably arranged on the base around a second axis, and the first axis and the second axis are arranged at an included angle; the workpiece comprises a first surface group and a second surface group which are adjacent to each other and form an included angle, and establishing a rectangular coordinate system in a first plane perpendicular to the first axis by taking an intersection point of the first axis and the first plane as an original point and taking a midline of the first target group and the second target group as an X axis, the included angle between the projection line of the first surface group on the first plane and the X axis is alpha, and the angle alpha is 40-50 degrees. By adopting the scheme, the problem that the coating uniformity on the surface of a workpiece is difficult to correct is solved.

The invention provides a parameter optimization method for a rotary cultivator with a low-speed small-bending-angle rotary blade, belongs to the field of agricultural mechanical equipment, and analyzes, researches and optimizes the bending angle of the existing rotary blade, the edge angle of the rotary blade and the rotating speed of a rotating body. The bending angle alpha of the rotary blade, the cutting edge angle beta of the rotary blade and the rotating speed n of the rotating body are used as test factors, the soil crushing rate M and the torque T are used as evaluation indexes, three-factor and three-horizontal orthogonal tests are carried out on the machine tool, and after range and variance analysis is carried out on the test results, the obtained better structure parameter combination is as follows: the bending angle alpha of the rotary blade is equal to 132 degrees, and the bending angle beta of the rotary blade is equal to 132 degrees; the edge angle beta of the rotary blade is 20 degrees, and the rotating speed n of the rotary body is 150 r / min; according to actual production requirements, the better structure parameter combination is adjusted as follows: the bending angle alpha of the rotary blade is equal to 132 + / -5 degrees, the cutting edge angle beta of the rotary blade is equal to 20 + / -2 degrees, and the rotating speed n of the rotary body is equal to 150 + / -10 r / min; the rotary cultivator used by the optimization method comprises a rack, a rotary body and a transmission assembly. The parameter optimization method is novel, the structural parameter combination is reasonable, the soil crushing rate is high, and the machine load is small.

The invention belongs to the technical field of aircraft design, and particularly relates to a variable-pitch pull rod adjusting and fixing device and method. The device comprises a base and four column bodies integrally formed with the base. U-shaped grooves are formed in the upper part and the lower part of the base; the side wall of the U-shaped groove is parallel to the side wall of the rectangular hole, and an angle alpha is formed between the side wall of the U-shaped groove and the vertical direction and ranges from 3 degrees to 8 degrees; the four columns are respectively positioned at four corners of the base; and the A surface of each column body is coplanar with the side wall of the U-shaped groove.

The utility model relates to the technical field of tunnel construction, in particular to an angle control tool for a tunnel feet-lock anchor pipe. The tool comprises a steel plate, a mounting base, a first support, a second support, a guide pipe and a steel frame, the steel plate is included, positioning assemblies are arranged on the two sides of the steel plate in a mirror symmetry mode, and each positioning assembly comprises a mounting base, a first support, a second support and a guide pipe; the second support and the first support are arranged on the mounting base from top to bottom, the second support is shorter than the first support, and the guide pipe is obliquely mounted above the first support and the second support. The inclination angle alpha between the guide pipe and the horizontal plane can be adjusted to be 10-20 degrees, it is guaranteed that the angle meets the standard requirement when the feet-lock anchor pipe is driven in, and therefore the grouting fullness and the steel frame stability are improved. The tool has the advantages of being easy to manufacture, convenient to construct, capable of being repeatedly used, safe, economical and the like, the problem that the angle of the anchor pipe is difficult to control in manual operation is effectively solved, and the steel frame sinking risk caused by the fact that the angle does not meet the standard requirement is reduced.

The molten iron pretreatment stirring device comprises a stirrer, the stirrer is obliquely inserted into molten iron, the included angle alpha between the stirrer and the horizontal direction is adjustable within the range of 20-60 degrees, the stirrer comprises a stirring rod and stirring rods, the multiple stirring rods are arranged in an axial symmetry mode with the stirring rod as the axis, the stirring rods are parallel to one another, and the stirring rods are parallel to one another. And the stirrer is driven to rotate by taking the stirring rod as an axis. Compared with the prior art, the method has the beneficial effects that 1, the stirring rod directly stirs the desulfurizing agent into the iron liquid, and good dynamic conditions for mixing the iron liquid and the desulfurizing agent are obtained; and 2, as the rotating flow field with the included angle of 20-60 degrees with the vertical direction is obtained, the material exchange rate between the slag and the molten iron is far higher than that of a traditional stirring method.

The invention relates to a wave-absorbing sponge for a ground experiment of an X-band microwave charging transmitting antenna. The wave-absorbing sponge is of a two-dimensional array structure, according to the geometric structure of the wave-absorbing sponge in one period, the bottom is a wave-absorbing sponge flat plate, the upper portion is a quadrangular wedge body, the lower surface of the quadrangular wedge body is a rectangular face, the other faces are triangular faces, and the width of the lower surface and the width of the periodic structure are both w, the length of the periodic structure is equal to the length l of the bottom wave-absorbing sponge flat plate in the period, the bottom edge of the lower surface is in contact with the surface of the wave-absorbing sponge flat plate and forms an included angle alpha with the surface, the thickness of the four-edge wedge body in the incident wave propagation direction is gradually increased, and the four-edge wedge body is periodically repeated in the horizontal x direction, so that the lower surfaces of the four-edge wedge body are seamlessly spliced together; the longitudinal direction periodically repeats in the y-direction. The device has the beneficial effects that ground microwave reflection in a microwave wireless energy transmission ground beam efficiency measurement experiment is inhibited, the accuracy of a measurement result is ensured not to be influenced by the ground reflection, the structure is simple, the cost is low, and the weight is light.

According to the special-shaped vibrissa knife, a first intersection line and a second intersection line on the inner wall of a shearing part of a static knife are located on two cutting faces respectively, the two cutting faces intersect to form an included angle alpha, and the inner wall of the shearing part of the static knife is only provided with one break angle due to the arrangement of the included angle alpha, so that the production process is simplified, and the manufacturing cost is reduced. Meanwhile, due to the clearance fit design of the cutting end of the movable cutter and the included angle alpha, the stability and accuracy of the vibrissa cutter in the cutting process are ensured, and the risk of accidentally injuring the inner wall of the nasal cavity is effectively avoided. In addition, due to the design of the included angle alpha, the movable cutter and the static cutter are matched more tightly, the vibrissa is effectively prevented from slipping off in the cutting process, and the cutting effect is further improved. When the cutting device is used, a user can feel smoother and more comfortable cutting experience, and meanwhile the possibility that repeated operation is needed due to incomplete cutting is reduced.

The invention belongs to the technical field of carbon fiber composite material processing, and discloses a composite material preforming ultrasonic cutting method. According to the method, the included angle alpha of blades on different sides and the included angle beta of blades on the same side of a cutter body are measured in advance, in the cutting process, the advancing direction of the cutter body and the fiber direction are controlled to form an included angle A, the included angle between the axis of the cutter body and the advancing direction is dynamically adjusted to rotate from an acute angle to an obtuse angle, and the maximum inclination angle of the cutter body is controlled to be larger than alpha / 2 for cutting of the inwards-concave arc-shaped face. And for plane cutting, the maximum inclination angle is controlled to be alpha / 2, so that the cutting edge is attached to the plane, extrusion to the composite material is effectively reduced through cutting along with the deformation angle, and the problems of material deformation, step difference, over-cutting and the like are avoided.

Device (6) for indicating marking positions (9, 10) on a surface (1) of a golf course, which device (6) is arranged relative to the surface (1), characterized by the fact that several bundles of light rays (4, 5) are emitted by at least one light source (2, 3), which bundles of light rays (4, 5) are directed from a high point (7, 8) spaced apart from the substrate (1) towards the substrate (1), wherein several patterns are projected onto the surface (1) by individual bundles of light rays (4, 5), wherein a single bundle of light rays (4, 5) marks a single marker position (9, 10) by a single pattern of the multiple patterns, wherein each bundle of light rays (4, 5) comprises a principal axis, which principal axis is oriented at an acute angle alpha, beta to the substrate (1) and / or to a horizontal axis, which angles alpha, beta are equal in magnitude, in which marking position (9, 10) a tee mark can be arranged.

A bending device for a special-shaped mini-fit contact pin comprises a base plate and a bending tool fixed to the base plate, the bending tool comprises an outer ring fixed to the base plate and a rotating disc which is driven by a driving mechanism to be rotationally matched in the inner circle of the outer ring, a positioning column vertically extending upwards is fixedly arranged on the outer ring, and the positioning column is fixedly arranged on the base plate. A turnover column vertically extending upwards is fixedly arranged on the rotary disc, one side wall of the positioning column is an inclined face and is matched with the inclined angle of the inclined face of the mini-fit base to form a positioning face, the side wall, facing the turnover column, of the positioning column forms a limiting face, and the included angle alpha between the limiting face and the positioning face is 90 degrees. The side wall, facing the positioning column, of the folding column forms a folding face, a spacing distance is formed between the folding face and the limiting face, the starting included angle beta between the folding face and the positioning face is matched with the angle between the contact pin and the inclined face of the mini-fit base, and the ending included angle gamma between the folding face and the positioning face is 90 degrees. The pin bending device is simple in structure, low in manufacturing cost and capable of efficiently and stably bending pins assembled by mini-fit, and product quality is guaranteed.

The invention discloses a processing machine rotating shaft rotation deviation detection method comprising the following steps that S1, a linear shaft and a rotating shaft of a processing machine are controlled to return to the zero position, a calibration disc is fixed to a workbench of the processing machine, and a plurality of detection points are arranged on the calibration disc; s2, controlling the rotating shaft to be detected to rotate to a preset theoretical angle beta, and collecting Z values of at least two detection points; s3, calculating a height difference H according to the Z value variation of the two detection points, and calculating an actual rotation angle alpha of the rotating shaft to be detected according to the height difference H and the distance L between the two detection points; and S4, judging whether the assembly of the rotating shaft is qualified or not according to the actual rotating angle alpha and the preset theoretical angle beta of the to-be-detected rotating shaft. According to the invention, the rotation deviation of the rotating shaft of the processing machine can be automatically detected, the detection efficiency is high, environmental pollution and equipment wear are avoided, the detection precision is more accurate than that of manual detection, and the detection cost is lower.

The application discloses a self-adaptive podium tilt angle adjusting method and processing terminal, and belongs to the method which comprises the following steps: step 1: obtaining a current posture index r of a speaker in front of a podium; step 2: calculating a podium tilt angle alpha corresponding to the current posture index r by a corresponding formula, wherein the corresponding formula comprises parameters A, B and C, A represents a change amplitude adjusting coefficient of the podium tilt angle, C represents a desktop tilt angle when the speaker stands straight without bowing or lifting the head, B represents a response speed of the podium tilt angle after the response to the posture change of the speaker, the current posture index r of the speaker in front of the podium is measured in real time, the podium tilt angle alpha corresponding to the current posture index r is obtained according to the current posture index r, and then the podium is adjusted to the podium tilt angle alpha, and the current podium tilt angle adjustment is completed. The application can well adaptively adjust the podium tilt angle under different postures, and the comfort and experience are improved.

The invention discloses a nailing device suitable for different pedicle screw threads and a thread design method of the nailing device, and belongs to the technical field of medical instruments. The screw feeding device comprises a main body, the head of the main body is provided with an external thread matched with an internal thread of a pedicle screw seat, the thread form of the axial section of the external thread is a right trapezoid, the long bottom edge is located on the thread tooth bottom side, the short bottom edge is located on the thread tooth top side, the vertical waist side face is a bearing face for bearing screwing torque, and the bearing face is perpendicular to the axis; and the included angle alpha between the guide inclined surface and the bearing surface is more than or equal to 0 degree and less than or equal to 18 degrees. The thread design method comprises the following steps: acquiring tooth form parameters of various pedicle screw internal threads; intersection fitting processing is carried out on the various internal thread profile contours, and a reference fitting contour is determined; and carrying out structure optimization on the reference fitting contour to form the external thread with the axial section being a right trapezoid. By means of the special thread form, the pedicle screw can be matched with pedicle screw threads of different tooth forms, and the pedicle screw implantation device is suitable for implantation operation of pedicle screws in orthopedic surgery.

The application discloses an indexable cutting blade and a cutting tool, and relates to the technical field of metal cutting, which comprises a front surface, a rear surface and a peripheral side surface, the peripheral side surface is arranged between the front surface and the rear surface and extends along the circumference of the indexable cutting blade, a cutting edge is formed between the peripheral side surface and the front surface, the front surface comprises a reference plane, a first rake surface and a second rake surface, a first included angle alpha 1 is formed between the first rake surface and the reference plane, a second included angle alpha 2 is formed between the second rake surface and the reference plane, and the second included angle alpha 2 is smaller than the first included angle alpha 1. The indexable cutting blade of the technical scheme works in the large rake angle area of the first rake surface when the cutting depth is small and the feed is large, so that the sharpness and surface quality are ensured, and when the cutting depth is large, the small rake angle area of the second rake surface is involved in the work, so that sufficient cutting edge strength and impact resistance are provided. The dynamic adaptability greatly expands the applicable machining range of the indexable cutting blade.

The invention belongs to the technical field of machining, and particularly relates to a machining method for a composite angle plane part, which comprises the following steps of: decomposing the composite angle plane of the part into two coplanar single-angle planes by using three-dimensional modeling software, and measuring an included angle alpha 1 and an included angle alpha 2 between an intersection line and a reference plane; adding materials to form a containing body containing part, and setting a positioning and clamping surface; by taking the containing body as a reference, processing an alpha 1 plane, a process step and a middle structure by using horizontal three-axis semi-equipment, and fixing by using industrial paraffin; and processing a reference surface by using vertical three-axis equipment and stripping the part by taking the process step as a reference, and heating to remove paraffin. Only three-axis / three-axis half equipment is needed, the standard is unified, the precision efficiency is improved, the cost is reduced, the universality is high, and the method can be popularized to similar parts.

The application relates to the technical field of forming turning processing, and discloses a forming tool chip rolling groove and a manufacturing method thereof, which comprises the following steps: S001: according to the radial dimension size of a processing object, the radius lengths of a first circular arc and a second circular arc are determined, and the difference between the radius lengths of the first circular arc and the second circular arc is at least greater than half of the radius length of the second circular arc; S002: according to the width of a forming surface, the included angle alpha between a straight line and a horizontal line is determined; S003: the first circular arc, the second circular arc and the straight line are connected through a preset mode; and S004: the first circle center and the second circle center are connected through a connecting line, and the connecting line forms the included angle beta with a vertical direction straight line. The forming tool chip rolling groove cannot adapt to the forming machining requirement of non-uniform and symmetrical distribution of cutting force, and the problem that the forming tool blade edge wear is intensified due to poor chip removal can be effectively avoided.

The invention relates to a hip replacement preoperative acetabular prosthesis positioning method based on a concentric circle principle, and the core of the method is that a coincidence point O of a femoral head center and an acetabular rotation center is determined based on imaging data before an operation, and a virtual concentric circle model is constructed by taking the point O as a circle center and an acetabular opening surface as a reference; the abduction angle of the acetabular prosthesis is preset to be 40 degrees, a straight line L passing through the rotation center O is drawn according to the angle, and the arc distance D between the point A and the straight line L on the spherical surface of the acetabular prosthesis is accurately calculated according to a formula by measuring the edge angle alpha of the acetabular center and the diameter R of the acetabular. The arc distance D is the arc distance from the acetabular outer upper edge bony mark point A to the acetabular prosthesis outer upper edge, which can be measured in the operation. Through preoperative accurate quantitative calculation, an objective and accurate navigation basis is provided for acetabulum filing and prosthesis placement in the operation, anatomical reconstruction of the hip joint rotation center is achieved, and the risk of complications such as postoperative dislocation and abrasion caused by the poor position of the prosthesis is remarkably reduced.

The invention discloses a compressor and refrigeration equipment, and relates to the technical field of compressors, the compressor comprises: a motor comprising a rotor and a stator; the pump body assembly comprises a crankshaft, a compression part and a silencer, and the silencer is located on the side, close to the rotor, of the compression part; the silencer comprises a bottom cover and a silencing cover, and the silencing cover is provided with an exhaust hole; the exhaust holes comprise a first exhaust hole, the first exhaust hole is provided with an exhaust plane intersecting with the circumferential direction of the silencing cover, the normal of the exhaust plane and the exhaust plane intersect at a point A, the projection circle center formed by the silencer on the axial projection plane of the silencer is a point O, an included angle alpha is formed between a straight line OA and the normal of the exhaust plane, and the included angle alpha is larger than 0 degree and smaller than 180 degrees; the radius of the outer circle of the silencing cover is R0, the maximum size of the first exhaust hole in the radial direction of the silencer is d0, and the outer diameter of a rotor iron core of the rotor is R1; the following is satisfied. According to the technical scheme, efficient noise reduction and performance optimization can be achieved on the premise that the height of the whole machine is guaranteed.

The application provides a self-positioning blade chord length gauge design method, which takes the X axis and Y axis of a blade as original reference, forms an L axis by an angle alpha between a measured size of the blade and the X axis, and sets a lower end measurement starting point of the measured size on a blade tail arc of the blade; selects three points A, B and C on the blade as reference design gauge plate shapes, the A reference and the C reference are straight line positioning respectively, the B reference is curve positioning, and a size measurement baseline of the blade is parallel to a reference axis of the measured size; calculates shape precision of the gauge plate, obtains sizes and curve point coordinates of the A reference, the B reference and the C reference; realizes self-positioning of the gauge plate and the blade by finding corresponding positioning of the A reference, the B reference and the C reference on the gauge plate, realizes quick and accurate measurement on site in batch production of chord lengths of blades with different shapes or sizes, and is low in cost.

The application relates to a method for connecting a lower structure and a pipe piece, belonging to the field of shield tunnels, and the method comprises the following steps: obtaining a final included angle alpha according to an included angle alpha1 and an included angle alpha2 between adjacent connecting bolt hole groups on the pipe piece, and confirming an included angle mu between two adjacent connecting bolt holes in a single connecting bolt hole group; the application realizes the connection between the pipe piece and the internal structure by using newly-added bolt holes or reconstructed existing holes on the pipe piece, the pipe piece is connected with the lower structure by being connected with the connecting bolt holes through bolts and matched connecting bolt holes, the stability of the lower structure during the construction period and the operation period is enhanced by arranging the connecting device between the lower structure and the pipe piece, and meanwhile, the lower structure installation under the centering condition of the internal structure and the pipe piece can be adapted.

The utility model relates to a kind of applied to the impeller of automobile electronic water pump outer rotor, by being arranged unevenly on impeller body blade, the included angle between first blade group, second blade group and third blade is kept consistent angle, this design is to ensure that water flow can be evenly distributed and reduce the formation of vortex and turbulent flow when impeller is high-speed rotation, and the included angle between first blade group and second blade group is different from included angle alpha, included angle beta and included angle gamma, such structure is to form a specific fluid passage in the inside of impeller.When water flow passes through this passage, it can be guided to a specific direction, and form stronger water flow in the direction, in addition, uneven blade design can effectively reduce the noise generated when water flow passes through impeller.Because the included angle and layout between blades are carefully designed, so that water flow can form more smooth flow when passing through impeller, reduce the noise generated due to water flow impact.

The utility model discloses an orthodontic appliance. The orthodontic appliance has a lip-tongue direction, a jaw-gum direction, and a mesiodistal direction. The orthodontic appliance comprises a bracket piece, a cover body piece and a traction piece, the bracket piece comprises a bearing body, a limiting body and a matching body, the bearing body is provided with an arch wire bearing face, and the limiting body and the matching body are fixedly arranged on the two sides of the arch wire bearing face at intervals to form an arch wire groove. The cover body piece is connected with the matching body in a sliding mode and has a closing state for closing the arch wire groove and an opening state for opening the arch wire groove. And the traction piece is fixedly connected with the limiting body. On the first plane, the arch wire bearing face is provided with a first center line, and the first center line and the lip-tongue direction are arranged in the same direction. The traction piece is provided with a first position point. The traction piece is provided with a second position point. The included angle alpha between a line segment formed by connecting the first position point and the second position point and the lip-tongue direction is larger than or equal to 30 degrees and smaller than 90 degrees. When the orthodontic appliance is used, a user is not prone to generating foreign body sensation.

The invention discloses an indexable cutting blade and a cutting tool, and relates to the technical field of metal cutting machining.The indexable cutting blade comprises a front surface, a rear surface and a peripheral side face, the peripheral side face is arranged between the front surface and the rear surface and extends in the peripheral direction of the indexable cutting blade, and a cutting edge is formed between the peripheral side face and the front surface; the front surface comprises a reference plane, a first rake face and a second rake face, a first included angle alpha 1 is formed between the first rake face and the reference plane, a first included angle alpha 2 is formed between the second rake face and the reference plane, and the second included angle alpha 2 is smaller than the first included angle alpha 1. According to the technical scheme, the indexable cutting blade works in the large front angle area of the first rake face during small cutting depth and large feeding, sharpness and surface quality are guaranteed, in the large cutting depth, the small front angle area of the second rake face intervenes in work, sufficient cutting edge strength and impact resistance are provided, and the cutting efficiency is improved. The dynamic adaptive capacity greatly expands the applicable machining range of the indexable cutting blade.

The utility model provides a shredding cutter of a filament placement machine, which relates to the technical field of composite material filament placement devices and comprises a cutter body, a cutter head and a mounting part. The cross section of the cutter body is rectangular, one end of the cutter body is provided with a cutter head, the other end of the cutter body is provided with a mounting part fixedly connected with a fiber placement machine head, the surface of the cutter head is in a slope shape, the transverse length of the cutter head is 5-55cm, the cutting edge inclination angle alpha of the cutter head is 10-70 degrees, the cutting edge inclination angle alpha is an included angle between an inclined cutter face and a horizontal line, and the front angle beta of the cutter head is 90-150 degrees. The rake angle beta is the inclination angle of the front end of the cutter face. The technical problems that in the prior art, shearing force of a straight-blade-shaped cutting knife is not concentrated, and a V-shaped cutting knife is not suitable for being integrated on a tow placement machine head due to the large size are solved, and the technical effect of improving the shearing force of tows is achieved.