CN111745231A

CN111745231A - Clamping structure of double-worm-wheel fly cutter

Info

Publication number: CN111745231A
Application number: CN201910236081.8A
Authority: CN
Inventors: 周湘衡
Original assignee: SINOSTEEL HENGYANG MACHINERY CO Ltd
Current assignee: SINOSTEEL HENGYANG MACHINERY CO Ltd
Priority date: 2019-03-27
Filing date: 2019-03-27
Publication date: 2020-10-09

Abstract

The invention relates to a clamping structure of a double-worm-wheel fly cutter, wherein a driven end of a cutter rod is provided with a central hole concentric with the cutter rod, two parallel mounting holes for mounting the fly cutter are arranged in the radial direction and are communicated with the central hole, the central distance between the mounting holes is the axial tooth pitch of a working worm, a positioning and clamping mechanism is arranged in the central hole, a force application component, a plurality of balls, a positioning ejector rod, a fly cutter, an elastic ejector rod and the like are sequentially arranged in the end surface of the driven end, the force application component generates axial force, the end surface of the opposite end of the positioning ejector rod slides to the flat plane of a straight shank of the fly cutter to form close surface contact, the two fly cutters are fastened in the corresponding mounting holes, and the cutting edge part of a head of the fly cutter is positioned at the same. The technical scheme weakens the strength and the rigidity of the cutter bar least, has simple structure, convenient use, high repeated positioning precision and large and reliable clamping force; because the clamping part is arranged in the central hole, conditions are created for realizing multi-fly cutter processing of the partial integral multi-head worm gear hob with the handle.

Description

Clamping structure of double-worm-wheel fly cutter

Technical Field

The invention relates to a clamping structure of a double-worm-wheel fly cutter, which is mainly used for the roll cutting of a cylindrical worm-drive multi-head worm wheel with a smaller working worm diameter and larger cutting force.

Background

When the worm gear is rolled, the basic geometric parameters of the worm gear hob generally need to be the same as that of a working worm (namely, the worm meshed with the rolled worm gear), so the worm gear hob is a special tool with strong pertinence, the utilization rate is low, the price is high, the production period is long, the use is not economical, the multi-head worm gear hob is difficult to manufacture, the worm gear hob is not economical in single piece small batch production, a fly cutter can be used for processing the worm gear, the fly cutter is the worm gear hob with not less than one tooth, and the tooth cutting principle of the fly cutter is the same as that of the tangential worm gear hob. The fly cutter has the main advantages and disadvantages of simple structure, convenient manufacture, low cost and low production efficiency; however, if the fly cutter and the cutter bar are properly designed, manufactured accurately, and used correctly, the precision of the processed worm gear is not lower than that of the worm gear hob, so that the fly cutter is one of the main factors for processing the worm gear. No matter whether the number of teeth of the worm gear and the number of thread heads of the working worm are integral multiples or whether the maximum common factor exists between the teeth and the thread heads, in order to reduce manual splitting (error) and improve gear cutting efficiency, cutter bar rigidity and the like, when the flycutter generally takes the axial tooth pitch of the working worm along the axial adjacent center distance of the cutter bar, interference between the flycutter and a positioning clamping part and weakening of the strength of the cutter bar at the position are easy to occur due to small structural size of the flycutter, and even the manufacturing difficulty of the cutter bar is caused; therefore, the axial tooth pitch of more than one working worm has to be adopted, the length of the cutter rod and the tangential feed length are additionally increased, the distance between the cutter rod seats supported by the driving end and the driven end of the cutter rod is longer, the lengthening rigidity of the cutter rod is weakened, the tangential feed time is prolonged, the rigidity and the strength of the cutter rod and the tooth cutting efficiency are influenced, even the quality of a tooth surface is limited by the limit of the tangential feed stroke of the machine tool, and the implementation is difficult or impossible. FIG. 1 shows a clamping structure for machining medium and small module worm flywheel cutters; the fly cutter round straight handle is arranged in a round hole of the cutter bar 1, the

nuts

3 and 4 are screwed down to enable the round sleeve 2 to move axially along the outer cylindrical surface of the cutter bar 1, the round sleeve 2 passes through the central line of the round sleeve 2 hole and is held tightly along the fly cutter round straight handle along a concave arc groove arranged axially, and the diameter of the cutter bar 1 is reduced to influence the strength because the round sleeve 2 moves axially along the outer cylindrical surface of the cutter bar 1; the cutter bar has simple structure and convenient adjustment, but has poor clamping reliability, and the concave arc groove has higher requirement, so the cutter bar is obviously not suitable for positioning and clamping the double worm gear fly cutter and the working worm with smaller diameter. Two clamping structures are provided for processing the large-modulus worm gear fly cutter, as shown in fig. 2 and 3, a nut is screwed to enable a round pull rod with a screw rod to axially move in a round hole, and a concave circular arc groove or an inclined plane arranged on a cylindrical part of the round pull rod is used for locking a plane of a fly cutter round straight handle or a plane of the fly cutter round straight handle respectively. The clamping structure has large clamping force and is not easy to loosen the fly cutter, but the two clamping structures are provided with the round pull rod and the round hole of the fly cutter along the radial direction of the cutter bar and are vertically crossed and penetrated, so that the strength and the rigidity of the cutter bar are weakened, and the structure of the vertically crossed hole is suitable for occasions with larger diameters and adjacent center distances of the working worm (the cutter bar), so that the use of multiple fly cutters is limited, and in order to avoid the difficulty in manufacturing the cutter bar of the multiple fly cutters and adjusting the fly cutter, a single fly cutter has to be used for replacing the cutter bar, and the production rate is reduced. Because the number of fly cutters is extremely small, the cutting amount is large, the cutting edges are easy to wear, the local wear increases the cutting resistance quickly, and because the fly cutter hobbing worm gear is fed tangentially, when the fly cutter is hobbing from a cutting-in end to a cutting-out end, the cutting edges of the fly cutters cut from one side to two sides and then cut from the other side, the fly cutter generates a large periodic alternating torque along the axial lead of the fly cutter, a circular straight handle of the fly cutter has a small gap with a round hole of the cutter rod and is influenced by the rigidity of the cutter rod and a supporting end and the gap of rotating parts such as a bearing, the dynamic rigidity is poor, the vibration is easy to cause, and the fly cutter is loosened, falls off and even damages the worm gear and the like under the action of alternating cutting impact; particularly, the diameter of the working worm is small, the modulus and the cutting force are large, and especially the cutting conditions of the cutting edges on two sides of the fly cutter with a large lead angle are greatly different, so that the clamping structure is difficult to be sufficient.

Disclosure of Invention

The invention aims to provide a positioning and clamping structure with the center distance between two worm wheel fly cutters as the axial tooth pitch of a working worm so as to improve the worm wheel productivity and the fly cutter durability; the clamping device is suitable for clamping a double-worm-wheel fly cutter with a small working worm diameter and a large modulus, and particularly suitable for rolling and cutting a multi-head worm wheel needing manual head division.

The technical scheme of the invention is as follows: the fly cutter comprises a cutter bar, wherein the cutter bar consists of an active end with a taper shank and a slender passive end, the passive end is provided with a central hole which faces the active end and is concentric with the rotation central line of the cutter bar, two parallel mounting holes for mounting fly cutters are radially arranged in the middle of the cutter bar along the rotation central line of the cutter bar, the center distance between the mounting holes is pi m in the axial direction of a working worm, the central line of the mounting holes is vertical to and passes through the rotation central line of the cutter bar and is communicated with the central hole, a positioning and clamping mechanism is arranged in the central hole, a force application component, a plurality of balls, a first positioning ejector rod, a first fly cutter and an elastic ejector rod are sequentially and inwards arranged from the end face of the passive end, the force application component, the second positioning ejector rod and the second fly cutter penetrate through a hole on the straight shank planing plane of the first fly cutter, and the cylindrical end of the elastic ejector rod is inserted into a concentric positioning, the force application component generates axial force to enable the end faces of the opposite ends of the first positioning ejector rod and the second positioning ejector rod to simultaneously slide to the flat plane of the straight shank of the fly cutter to form close surface contact, the two fly cutters are fastened in the corresponding mounting holes, the cutting edge parts of the two fly cutter heads are positioned at the same part of the working worm, and the direction of the cutting edge parts of the two fly cutter heads extending out of the cutter rod is the same, and the rake face with zero rake angle of the fly cutter faces the rotating direction of the fly cutter during working.

By adopting the technical scheme, the center distance of the double worm gears axially arranged on the two adjacent threads is the minimum, so that the elastic ejector rod is the shortest, the double flying cutters are convenient to position and clamp, the tangential stroke of the flying cutters is the shortest, the productivity is the highest, and a positioning and clamping mechanism is arranged in the concentric center hole of the cutter bar, so that the length of the cutter bar can be set to be the shortest and the diameter is the largest, and in terms of material mechanics, the influence of the center hole on the strength and the rigidity of the cutter bar is the minimum, and the strength and the rigidity of the cutter bar are the largest, which is very important for the worm gear with; the fly cutter is sharpened in the process of precise gear cutting, because step difference can occur on the tooth surface, the tooth thickness difference can also occur on a multi-head worm gear, the durability between the two times of regrinding of the fly cutter is very important, and the point is particularly critical for the multi-head precise worm gear which has large modulus and more teeth and is made of harder material. Meanwhile, according to the working conditions, the combination of fly cutter groups (such as coarse and fine) with different cutting performances, a feed (radial, constant or variable tangential feed) mode, a tooth profile and the like can be arranged, so that the advantages of the fly cutter groups are fully exerted, the productivity and the tooth cutting efficiency are improved, and the tooth profile precision and the productivity of the fly cutter hobbing worm gear are improved in the prior art.

The positioning and clamping mechanism is arranged in the center hole, so that the space is not occupied, the structure is simple and compact, the ball is used as a force transmission medium, the work is flexible, the rolling friction loss is less, the first positioning ejector rod is short, the first positioning ejector rod can move and rotate freely in the center hole, a lubricant can be stored in the closed center hole, the lubricant is not easy to run off and can be prevented from being polluted, the positioning and clamping mechanism can move flexibly and is rust-proof, the maintenance is reduced, the positioning plane arranged in the mounting hole is combined with the opening gasket, the online measurement is realized by means of a measuring device, the fly cutter can be positioned accurately in the radial direction on the cutter rod, the movement towards the center of the cutter rod after the cutting force is applied is prevented, the. Under the action of force generated by a force application member, the inclined end faces of the opposite ends of the positioning ejector rod slide to the straight shank flattening plane of the fly cutter to form close surface contact, the two fly cutters are fastened in the mounting holes corresponding to the cutter bars, the cutting edge parts of the two fly cutter heads are positioned at the same part as the working worm, and the direction of the cutting edge parts of the two fly cutter heads extending out of the cutter bars is the same as the rotating direction of the rake face with zero front angle of the fly cutter during the operation of the fly cutter. The method creates conditions for the whole worm gear hob with a handle to realize fly cutter processing, can solve the bottleneck that a multi-head worm gear hob with a small diameter of part of working worms is difficult to manufacture, is suitable for rough cutting teeth with large cutting depth and large feeding amount because the fly cutter is not retreated forever by arranging the opening gasket, particularly adopts finish cutting teeth with small tangential feeding amount, conforms to the principle that the fly cutter can artificially improve the tooth profile precision, and greatly improves the productivity, particularly the multi-head worm gear with large modulus and small tooth number, so that the fly cutter and the cutter bar are properly designed, conditions are created for correct use and maintenance, the precision of the processed worm gear is not lower than the precision of the worm gear hob, and the worm gear has higher productivity.

Length of path L of cutter cutting in hobbing_P(high speed Steel) or number of cycles N to bear load_P(hard alloy) has great influence on the service life of the cutter, so the technical scheme of large cutting depth and large tangential feed is adopted to reduce L_PAnd N_PThe influence on the durability of the fly cutter to improve productivity and tooth surface quality and durability between two regrinding of the fly cutter, so that the optimized cutting amount is one of the conditions under which the fly cutter is used properly.

When the number of teeth of the worm gear and the number of thread heads of the working worm are integral multiples or the maximum common factor exists between the teeth and the thread heads, if manual splitting is not performed, the number of the fly cutters (groups) on the continuous adjacent heads is not less than the integral multiple or the maximum common factor, and each fly cutter is not less than one, all tooth sockets of the worm gear can be cut in one-time feeding, otherwise, manual splitting is required, manual splitting can be reduced or not required by adopting double-worm-gear fly cutters, manual splitting errors are reduced, and the production rate is improved.

When the number of teeth of the worm gear and the number of thread heads of the working worm are not integral multiples or the maximum common factor is not existed between the teeth and the thread heads, automatic splitting is performed at the moment, namely all tooth grooves of the worm gear can be cut in one feed by using one flying cutter; when one fly cutter is only used as 'invalid envelope cutter tooth', the cutting edges of the fly cutter are provided with chip separating grooves or waveform blades (hereinafter referred to as blade shapes) or the tooth tops of the fly cutter are slightly heightened, so that the top blades of the fly cutter with 'effective envelope cutter tooth' (with cutting and envelope functions) do not participate in cutting, thereby changing cutting patterns and improving cutting conditions, in particular to the technical scheme that the tooth tops of the fly cutter are slightly heightened and the blade shapes are very important for the fly cutter with few tooth numbers, the cutting conditions and local abrasion of the 'effective envelope cutter tooth' fly cutter can be effectively improved, the technical scheme of chip separating grooves and the like is adopted, rolling cutting with large cutting depth and large feed amount is realized, the cutting efficiency and the production rate as well as the durability of the fly cutter are greatly improved, the final tooth surface envelope effect (precision) of a worm gear is not changed under the condition of the same tangential feed amount, the defect that the 'invalid envelope cutter tooth' has no envelope function is converted into the advantage, therefore, wide thin cuttings are divided into narrow and thick cuttings, the II-shaped cuttings with the worst cutting conditions are eliminated, the deformation of the cuttings is reduced, the cutting force and vibration are reduced, no cuttings are wound, the cuttings are convenient to remove chips and heat dissipation, the friction of the cuttings on the front cutter face of the fly cutter is reduced, the power consumption is reduced, the cutting is stable, the cuttings form chips in a controlled mode, the machined tooth face is not damaged, the peak value of the cutting load is decomposed and reduced, the wear of the fly cutter is uniform, the service life of the fly cutter is prolonged, the durability between two times of regrinding of the fly cutter is further improved, the fly cutter is suitable for efficient cutting of rough cutting tooth sockets, and the combination form of the edge-shaped structure of the cutting edge of the fly cutter and the fly cutter is optimized. When the number of teeth of the worm gear and the number of thread heads of the working worm are integral multiples or the maximum common factor exists between the teeth and the thread heads, a fly cutter can be provided with a chip separating groove to improve cutting conditions and the like, but the manual head separating times are multiple. Therefore, the chip dividing groove or the wave-shaped blade is one of the conditions for designing and using the fly cutter correctly, and conditions are created for optimizing efficient and powerful cutting with large cutting consumption.

Compared with the radial feed method, the fly cutter hobbing (tangential feed) has the fundamental difference of cutting amount (force), because the fly cutter is the tangential feed generated by continuous tooth division and generation, the fly cutter always turns from a gear blank to one side of the end to cut tooth by tooth, the fly cutter (or the fly cutter cutting end) additionally bears the cutting amount which is cut by one side of other cutter teeth of the radial worm hob, the cutting load of the fly cutter is increased, the number of the fly cutters is extremely small, the cutting amount is large, the cutting resistance is also large, the peak value of the cutting load is extremely large, the wear of the fly cutter is uneven and quick, so that the fly cutter fails in advance, the improvement of the productivity is seriously restricted, the fly cutter has simple structure and small geometric dimension, the material taking and the manufacturing are convenient, the high-precision high-performance high-hardness fly cutter is easier to obtain than the hob, the edge shape, the cutting angles, the structural forms, the materials and the like of the rough cutter are improved through optimization, therefore, the cutting conditions (environment) of the fly cutter are improved, the existing defects are overcome, and the optimization of the improved rough cutting fly cutter (group) is the key for improving the productivity.

No matter whether the number of teeth of the worm gear and the number of thread heads of the working worm are integral multiples or whether the maximum common factor exists between the teeth or not, the double-worm-gear fly cutter can be divided into a coarse-cutting tooth group and a fine-cutting tooth group to improve the productivity (tooth cutting efficiency) and the tooth profile precision (contact spot), when the coarse-cutting tooth fly cutter group is used, the double-worm-gear fly cutter can be hobbing and adjusting according to a radial feeding method, namely, a machine tool only moves in tooth division and does not move in additional generation (tangential direction), so that the tangential feeding movement (transmission chain) is reduced, the rigidity of a machine tool-cutter process system is improved, the strength and the rigidity of the cutter bar are maximum, the fly cutter can be accurately positioned on the cutter bar and firmly clamped without retreating, the chip dividing groove technology and the like by combining the cutter bar of the invention, the double-worm-gear fly cutter is suitable for the powerful and efficient cutting of a coarse-cutting tooth groove, therefore, the productivity is not as high as that of the radial feeding method, the advantage that the edges on two sides of the hob teeth of the radial feeding method participate in cutting is exerted, the cutting allowance is uniform, and the subsequent gear cutting condition is improved; the design principle of the rough cutting tooth fly cutter set is as follows: the double-fly cutter has the advantages that firstly, the cutting load of the cutting fly cutter can not be too heavy, the tooth crest height of the cutting fly cutter is slightly higher than that of the fine cutting tooth fly cutter, the optimized cutting edges (such as chip dividing grooves) and cutting angles (such as special cutter sharpening rake faces), and the cutting loads with different tooth heights, tooth profile angles and tooth thicknesses are uniform; when rough cutting teeth are cut, the central line between the two worm-gear fly cutters passes through the center of the gear blank, after the rough cutting teeth are finished, the motion relationship between the machine tool and the cutter is kept unchanged, the fly cutters are moved tangentially, the fine cutting teeth fly cutters are replaced, and the linkage starts the generating motion and performs hobbing by using small tangential feeding amount. The technical scheme fully exerts the advantages of the fly cutter in different feeding methods and different cutting performances, the respective advantages of the blade shape and the tooth shape of the fly cutter, the optimized cutting edges and the respective advantages of the process system, can balance or reduce the peak value of the cutting load, effectively improve the cutting conditions of rough cutting and fine cutting, further improve the productivity and the durability of the fly cutter between two times of regrinding so as to improve the tooth shape precision and the productivity, and ensure that the tooth shape precision and the productivity of the fly cutter hobbing worm wheel are improved in the prior art. The advantages of the respective edge shape and tooth shape of the fly cutter with different feeding methods and different cutting performances, the optimized cutting edges and the process system are fully exerted, the process design creates conditions for optimizing the cutting amount, and the optimized cutting amount is one of the conditions for using the fly cutter correctly.

The double fly cutters of the fine cutting tooth fly cutter group can also adopt a coarse-fine cutter matching scheme according to working conditions (such as hard tooth surfaces), namely, the double fly cutters are alternately and circularly cut on the same tooth surface by utilizing the dividing heads, so that the fine cutting tooth process scheme is optimized, and the durability between two times of regrinding of the fine cutting tooth fly cutters is improved. The effective cutting depth of the chip dividing groove or the concave part of the waveform blade is matched with the feed amount and the cutting track of the fly cutter, thereby being more beneficial to improving the narrow and thicker chips and balancing or reducing the peak value of the cutting load, improving the chip discharging, breaking and high-efficiency tooth cutting effects, being beneficial to hobbing with large cutting depth and large feed amount, creating conditions for optimizing the cutting amount, reducing the feed times, improving the tooth cutting efficiency and the durability of the fly cutter, and therefore, the optimized process design scheme is one of the conditions for using the fly cutter correctly.

Because the fly cutter hobbing does not have the principle error of hobbing cutter hobbing, and the fly cutter has simple structure and is mostly single-tooth, the manufacture and the grinding are convenient, the cost is low, and the fly cutter with high precision, high performance and high hardness is easier to obtain than the hobbing cutter; the number of the broken line segments of the enveloping tooth shape can be manually and freely controlled in the tooth cutting process, namely the tangential feed amount is adjusted and is inversely proportional to the tangential feed amount and is irrelevant to the number of the worm gears; the fly cutter has no problem of a chip groove of a hob, chips can be freely curled, the phenomenon of chip blockage caused by insufficient chip containing space is avoided, the friction work and friction additional deformation when the chips flow out are small, the plastic deformation and cutting force during cutting are reduced, the chips are formed and smoothly flow along a front cutter face, the chips fall off under the action of self weight, the heat dissipation is good, and the cutting resistance and the power consumption are small. The open type front cutter surface is convenient for improving cutting conditions (environment), if a fly cutter can grind an optimized cutting angle on the edge of the front cutter surface according to materials, cutting amount, experience and the like, a hob cutter cannot be used; if the cutting area is directly centered and cooled, the hob is difficult to implement due to the chip grooves. The fly cutter can create better cutting conditions (environment) than a hob, and particularly has advantages for the fly cutter for the worm gear, which has higher requirements on the mobility, higher tooth surface hardness and the like.

Flying cutters, which are not commonly known to those skilled in the art, have two major advantages over hobs, the most fundamental of which are: the flywheel type high-precision high-hardness flywheel knife has the advantages that enough space which is easy to control is reserved for the design of a sharpening process of the flywheel knife, namely, the optimized cutting angles (such as special sharpening front knife faces) of cutting edges (such as chip dividing grooves) can be flexibly sharpened according to different worm gears and working conditions, the flywheel knife can be conveniently processed by adopting excellent materials and surface or cutting edge strengthening treatment and the like to obtain the flywheel knife with high precision, high performance and high hardness, the productivity and the tooth cutting efficiency are improved and the service life of the flywheel knife is prolonged on the premise of ensuring the required precision, and particularly, the blade shapes with different performances and the optimized cutting angles can be conveniently designed and sharpened according to the precision, the material, the working condition, the experience and the like of the worm gears to be cut on a tooth cutting site. The most essential advantages and disadvantages compared to the radial feed method are: 1. because the number of the broken line segments enveloping the tooth form of the worm gear is inversely proportional to the magnitude of the tangential feed amount, the production rate is proportional to the broken line segments, and the stroke times of each tooth pitch, namely the number of the broken line segments spread by the fly cutter, can be adjusted in a wide range according to the precision (contact spot) requirement of the worm gear to be cut, modulus, tooth number (or the ratio relation with the head number), lead angle, material, production rate and the like; the number of the broken line segments is large, the tooth profile has small edge degree, the tooth profile precision is high, and the tooth surface roughness is small. The number of broken line segments is in direct proportion to the number of chip grooves of the hob and in inverse proportion to the number of heads of the hob during radial hobbing, and the number cannot be increased or decreased by changing processing conditions; therefore, according to the required precision and working condition of the worm wheel to be cut and the like, the machining condition is changed, namely the tangential feed amount is adjusted, so that the contact spot (tooth profile precision) and the productivity can be manually controlled in the tooth cutting process, particularly, the tangential feed amount is changed by numerical control to obtain the optimal contact spot (the tangential feed amount is reversely obtained according to the requirement of a broken line segment) and higher productivity or higher productivity in rough cutting (the larger tangential feed amount is used in a section with smaller cutting force), and principle errors (such as over cutting of radial feed) do not exist, which is particularly important for multi-head worm wheels with large modulus and small tooth number; meanwhile, the cutting length of the tangential feeding method is large, so that the cutting track length of the cutter or the cycle number of bearing load is increased, the fly cutter additionally bears the cutting amount which is cut by other cutter teeth of the radial hob, the cutting load of the fly cutter is increased, the cutting amount of the fly cutter is extremely small, the cutting resistance is large, the fly cutter is worn in advance, particularly the local wear is fast, and the productivity and the durability of the fly cutter are not as high as those of the radial feeding method. 2. The maximum cutting speed of the fly cutter is influenced by the red hardness of a processed material and the fly cutter material and the rigidity of a process system, the cutting speed of the fly cutter is increased and the tangential feed amount is increased as much as possible under the condition of ensuring the tooth profile precision and the durability of the fly cutter, so that the tooth cutting efficiency is improved, and the cutting speed and the tangential feed amount can be independently selected and can be optimized. The characteristics are fully exerted, the fly cutter process design and the cutting amount can be optimized, conditions are created for powerful and efficient cutting, and the fly cutter design and use conditions are also one of the conditions for correct use.

The opening washer of the invention ensures that the fly cutter is accurately positioned and firmly clamped on the cutter bar, the strength and the rigidity of the cutter bar are maximum, the rigidity of a machine tool-cutter process system is good, the respective advantages of the edge shape and the tooth shape of the fly cutter (group) with different feeding methods and different cutting performances, optimized cutting edges and the process system are fully exerted, the advantages of the fly cutter are fully exerted, for example, the conventional fly cutter with only one layer of cutting edge is designed into a step two-layer cutting edge to simultaneously process one tooth surface, the fly cutter (group) with high precision, high performance and high hardness is easier to obtain than the hob, for example, the technical scheme that the tooth crest height of the fly cutter is slightly increased and a chip dividing groove is adopted, the cutting conditions (environment) of rough cutting and fine cutting teeth can be effectively improved, the cutting conditions better than the hob are obtained, conditions are created for adopting the optimal large cutting speed, large feeding amount and large cutting depth, the tooth cutting efficiency and the durability of the fly cutter are improved, and the flying cutter has the characteristics of no principle error, no chip groove, convenient chip removal and the like, so that the productivity of the flying cutter hobbing worm gear is improved in the prior art, and the precision is higher than that of the worm gear hobbing cutter.

The further technical scheme of the invention is as follows: the mounting hole is selected from one of a round hole, a square hole, a blind hole and a stepped hole, and the mounting hole and the positioning part of the fly cutter straight shank are straight holes.

The further technical scheme of the invention is as follows: the size and the shape of the mounting hole are the same, a positioning plane is arranged at the inlet end of the straight shank of the fly cutter of the mounting hole, the distance from the positioning plane to the rotation center line of the cutter rod is consistent, distance size numerical value inscription marks are made, an opening gasket is arranged between the positioning plane and the positioning plane of the cutter head of the worm gear fly cutter, and the positioning plane is perpendicular to the center line of the mounting hole.

By adopting the technical scheme, the sizes and the shapes of the installation holes are the same, the inlet end of the straight shank of the fly cutter of the installation hole is provided with the positioning plane, the positioning plane is used as an installation positioning reference with the consistent distance to the rotation center line of the cutter bar, and distance size numerical value inscription marks are made, so that the fly cutter is convenient to exchange, manufacture and install.

The further technical scheme of the invention is as follows: the force application member is optionally one of

The force application component adopts a screw with a square cylindrical end, axial force is generated when the screw is screwed down, and a force application terminal of the force application component and a thread part of the force application component for generating force are integrated.

By adopting the technical scheme, the spiral clamping mechanism plays roles of clamping, boosting and self-locking, is a common simple and reliable clamping mechanism, particularly has the advantages of large boosting, good self-locking performance, convenient use and the like, and the force generated by the thread is constant when the product of the external (acting) force and the force arm is constant.

The force application component adopts an electro-hydraulic push rod or a liquid, pneumatic cylinder and a gas-liquid force increasing mechanism, liquid, pneumatic pressure or electricity is used as energy to generate axial force, a piston rod of the hydraulic cylinder or the pneumatic cylinder is used as a force application terminal, and an interface connected with electricity, liquid and gas is arranged on a rotation center line of the force application component.

By adopting the technical scheme, when a hydraulic cylinder or a pneumatic cylinder is adopted, the pressure receiving area S of the piston is fixed, the pressure F is in direct proportion to the pressure P, namely F is PS, the corresponding pressure can be increased by increasing the pressure, and because the aperture of the central hole is small, a plurality of pistons can be connected in series and superposed to form a double reinforcement for avoiding the inconvenience of overhigh pressure; the pressure intensity of the hydraulic oil is much higher than the air pressure, so the diameter of the cylinder can be much smaller than that of the air cylinder, and a force-increasing mechanism is not needed usually, so the structure is simpler and more compact; the liquid is incompressible, so that the clamping rigidity is high, the work is stable, the clamping is reliable, and the noise is low; the energy of a gas-liquid force increasing mechanism formed by combining gas and hydraulic pressure is compressed air, and hydraulic oil is pressurized by superchargers with different sections and then enters a hydraulic cylinder to enable a piston rod to work; hydraulic or pneumatic cylinders are provided with valves or locks such as one-way valves to make them self-locking. When the electro-hydraulic push rod is used, the motor rotates positively and negatively to drive the bidirectional hydraulic pump to output pressure oil positively and negatively, and the pressure oil is sent to the oil cylinder through the hydraulic control valve to realize the reciprocating motion of the piston rod. The hydraulic flexible transmission mechanism has the advantages of being suitable for places needing reciprocating push-pull linear motion or clamping work and the like, capable of being automatically controlled, very reliable in overload automatic protection function, capable of being started in a loaded state, capable of stepless adjustment of force, adopting full hydraulic transmission, very sensitive in action, stable in operation, capable of buffering external impact force, small in occupied space, self-locking, free of a liquid (air) pressure station, convenient to operate with a power supply, and capable of integrating mechanical, electrical and liquid into a whole. By adopting the technical scheme, electricity, liquid or air pressure can be used as energy, and the axial force generated when the pressure intensity is constant.

The force application component adopts a spring or a spring assembly, the spring is uniformly and elastically deformed after being stressed and compressed, the elastic force generates axial force to push the force application terminal to move axially, and the elastic force is adjusted by using an adjusting flat washer or a screw. The spring assembly can be formed by connecting a plurality of disc springs in series or using cylindrical spiral compression springs with different diameters in a sleeved and overlapped mode.

According to the technical scheme, the Hooke's law shows that when the spring is elastically deformed, the elastic force F is in direct proportion to the extension amount (or compression amount) x of the spring, namely F is kx, the constant elastic force x is constant, k is the elastic coefficient of the material, is determined by the properties of the material, is independent of other factors, is increased by utilizing the change of the length of the spring, and has a buffering effect on the impact force.

The further technical scheme of the invention is as follows: the elastic ejector rod is provided with a composite assembly of a ball, an adjusting screw and a spring, and one end of the elastic ejector rod corresponding to the second positioning ejector rod is the ball.

By adopting the technical scheme, the elastic ejector rod is arranged between the first positioning ejector rod and the second positioning ejector rod, the elastic ejector rod is adjusted by the adjusting screw (a method for changing the extension length of the screw) or the size change of the fly cutter straight shank leveling plane on the cutter bar rotation central line is compensated, and the fly cutter straight shank leveling plane is adjusted to a correct position along the axial direction of the fly cutter straight shank leveling plane after being abraded and reground, so that the problem that the two fly cutters are not interfered when clamped in the central hole is solved, and the clamping force of the two fly cutters tends to be consistent: the ball is arranged for realizing that the end faces of the opposite ends of the first positioning ejector rod and the second positioning ejector rod simultaneously slide to the plane of the straight shank of the fly cutter to form close surface contact, and for enabling the end faces to move axially and rotate flexibly in the central hole and avoiding the blocking phenomenon. According to Hooke's law, if the compression quantity is constant, the elastic force is increased by using the change of the length of the spring, and the spring has a buffer effect on the impact force. The adoption corresponds to the one end of second location ejector pin is the ball, makes it have automatic aligning ability to compatible or offset elasticity ejector pin with the manufacturing and the installation error of location ejector pin improve its life and tight reliability of clamp, and with the equivalent friction radius of the terminal surface (point contact) of second location ejector pin is zero, improved transmission efficiency with the location ejector pin is in the flexibility of centre bore internal rotation is favorable to more the looks remote site terminal surface of location ejector pin slides extremely form inseparable face contact on the fly cutter straight shank planishing plane.

The further technical scheme of the invention is as follows: the force application component is positioned and connected with the central hole, or the force application component is positioned with the central hole in a sliding way and connected with the end face of the driven end of the cutter bar.

The further technical scheme of the invention is as follows: the thread of the inlet end screw hole of the central hole can be selected as a single-thread or a single-thread fine thread.

By adopting the technical scheme, the fine thread has better force increasing and self-locking effects than the coarse thread.

The further technical scheme of the invention is as follows: the screw thread of the screw hole at the inlet end of the central hole is selected from one of rectangular screw thread, trapezoidal screw thread and common screw thread, and is selected from rectangular screw thread.

By adopting the technical scheme, under the same condition, the thread form angle of the rectangular thread is zero, so that the equivalent friction angle is also zero, and the rectangular thread has better force increasing and self-locking effects.

The further technical scheme of the invention is as follows: the positioning and clamping mechanism is optionally provided with one of lubricating wax, calcium-based grease, molybdenum disulfide or thin oil, and the lubricating wax is selected from the lubricating wax.

By adopting the technical scheme, under the same condition, the friction force is reduced, the movement is flexible, the assembly and disassembly are convenient, the transmission efficiency and the reinforcement effect are improved, and the rust resistance is realized; the lubricating wax is not sticky with dust, is convenient to use, is not easy to lose, is less polluted, is safe and harmless, has long service life, avoids oil drying or no lubrication, particularly avoids the adhesion formed by lipid oil, and is not easy to lose and be polluted because the central hole provides a closed space for storing the lubricating agent.

The further technical scheme of the invention is as follows: the inlet end of the central hole is provided with a concentric thimble hole which is a 60-degree taper hole.

The further technical scheme of the invention is as follows: the force application terminal end face of the force application component is a straight end face and is subjected to hardening treatment.

The further technical scheme of the invention is as follows: the included angle between the fly cutter straight shank flattening plane and the fly cutter straight shank axial lead is an acute angle theta or 0 DEG, in order to enable the end faces of the opposite ends of the first positioning ejector rod and the second positioning ejector rod to simultaneously slide to the fly cutter straight shank flattening plane to form close surface contact, the inclined angle between the end faces of the opposite ends of the first positioning ejector rod and the second positioning ejector rod is theta or 0 correspondingly.

By adopting the technical scheme, when the cutter bar is clamped (the force application component) along the axial direction, the intermittent cutting force always faces to the center of the cutter bar, when the opening direction of the acute angle theta faces to the fly cutter head (the big end of the acute angle theta is in the direction of the fly cutter head), the force application component generates a component force towards the fly cutter head on the fly cutter, at the moment, the intermittent cutting force enables the fly cutter and the wedge (surface) to generate force increasing and self-locking effects, namely, the larger the cutting force is, the tighter and firmer the fly cutter wedge is, the dynamic rigidity between the cutter and the cutter bar is good, and meanwhile, the intermittent cutting force generates direct impact on the positioning and clamping mechanism; when the opening direction of the acute angle theta faces to the straight shank of the fly cutter (the large end of the acute angle theta is in the direction of the straight shank of the fly cutter), the force application component generates a component force to the fly cutter, which is back to the head of the fly cutter, and at the moment, the intermittent cutting force enables the fly cutter and the inclined plane not to form a wedge, so that the boosting and self-locking effects are not generated, and the intermittent cutting force does not directly impact the positioning and clamping mechanism; when the included angle theta between the planishing plane of the straight shank of the fly cutter and the axial lead of the straight shank of the fly cutter is 0 degree, no inclined plane structure exists, so that no inclined wedge force increasing and self-locking conditions exist, the force applying component does not generate component force to the fly cutter back to or towards the tool bit of the fly cutter, and the intermittent cutting force does not directly impact the positioning and clamping mechanism.

The smaller the acute angle theta is, the better the double superposition force-increasing effect of the cutting force and the wedge is, the more the self-locking performance is ensured, and when the conditions of wedge force-increasing and self-locking are not met (namely theta is 0 degrees or the inclined plane has the acute angle theta but does not form the wedge without the wedge tendency), the fly cutter can not loosen under the action of the force application component and the opening washer; another important characteristic of the ramp structure is the clamping stroke (i.e. axial movement in the central bore) and the distance over which the fly cutter moves correspondingly in its axial direction, and a reduction of the acute angle θ increases the sensitivity of the fly cutter to displacement in its axial direction, which is advantageous for achieving multiple regrinding (economy) of the fly cutter after wear, but is disadvantageous for adjusting the axial positioning accuracy, for which reason the acute angle θ should not be chosen too small.

The further technical scheme of the invention is as follows: the value range of the acute angle theta is between 3 degrees and 6 degrees.

The invention further adopts the technical scheme that: the acute angle θ is 4.5 °.

Since the flyer is fed tangentially, sometimes only one side blade participates in cutting and cutting angle problems, and the cutting forces of the two side blades are unequal, so that the flyer tends to rotate and move axially. And analyzing from the positioning, the fly cutter rotates and moves around the axis line of the fly cutter, the two planes of the straight shank of the fly cutter and the positioning ejector rod are tightly attached after clamping, and the degrees of freedom in the two directions are limited under the combined action of the positioning plane of the head of the fly cutter, the opening gasket and the cutting force.

The position of the fly cutter along the axial lead direction is determined by adjusting the thickness of the split washer and is clamped by axially moving the positioning ejector rod due to the adoption of the clamping and positioning of the split washer and the inclined surface, so that the tooth thickness of the fly cutter is still kept on the indexing cylinder of the working worm after the abrasion and regrinding of the fly cutter are axially adjusted. The axial positioning precision of the fly cutter is insensitive to the moving distance of the positioning ejector rod, the repeated regrinding performance of the fly cutter is improved, the degree of freedom of the fly cutter rotating around the axial lead is limited, the fly cutter depends on the contact precision of two planes, and the fly cutter is convenient to adjust.

By adopting the technical scheme, the positioning and clamping mechanism is arranged in the central hole, so that the length of the straight flying cutter handle is inevitably greater than that of the central hole, the contact length of the straight flying cutter handle is increased, the relative positioning is more reliable, the stability is good, and the repeated positioning precision and the service life of the mounting hole are improved.

By adopting the technical scheme, the end face of the positioning ejector rod of the positioning and clamping mechanism is a plane, the contact area is large, the clamping and positioning mechanism is simple and reliable, the positioning precision is higher, particularly, the fly cutter and the wedge (the plane) generate force increasing and self-locking effects by the spiral clamping mechanism and the cutting force, and the clamping reliability and the self-locking performance are improved. When the force application component applies force, the two planes are tightly attached to each other under the combined action of the opening gasket, and meanwhile, the fly cutter is accurately positioned and clamped on the cutter bar.

The further technical scheme of the invention is as follows: the outer circumferential surfaces of the first positioning ejector rod and the second positioning ejector rod are provided with a plurality of sections of circular grooves with guide angles, and the circular grooves are arranged at the two ends and two end surfaces of the first positioning ejector rod and the second positioning ejector rod in a hardening way.

The further technical scheme of the invention is as follows: when the fly cutter is tightly clamped on the cutter bar, the included angle between the fly cutter straight handle flattening plane and the fly cutter zero-front-angle front cutter face is determined according to the type, the precision grade, the size and the rotary direction of a work worm indexing cylindrical lead angle, so that the fly cutter zero-front-angle front cutter face is just positioned on the normal direction or the axial plane of the work worm; when the fly cutter zero rake face is just in the normal plane of the working worm, the included angle between the fly cutter straight shank planing plane and the fly cutter zero rake face is equal to the indexing cylindrical lead angle gamma of the working worm, and when the fly cutter zero rake face is just in the axial plane of the working worm, the included angle between the fly cutter straight shank planing plane and the fly cutter zero rake face is 0 deg.

By adopting the technical scheme, the difference of cutting force and cutter bar diameter, metal or nonmetal, material strength (property) and manufacturing convenience are comprehensively considered when the fly cutter shaft and the normal clamping are carried out, the means for sharpening the front cutter face, the tooth form and the cutting conditions of the cutting edges at two sides are different, such as hobbing Archimedes worm wheel, when the front angle of the fly cutter is 0 DEG, the tooth form of the fly cutter in the axial direction is a straight line, the working front angles of the cutting edges at two sides are different (the front cutter face is ground by adopting a special edge grinding method for improving the cutting conditions), the tooth form of the fly cutter in the normal direction is a (drum-shaped) curve which is the same as the normal section of the Archimedes worm, and the working front angles of the cutting edges at two sides are the same.

The invention has the beneficial effects that:

1. by adopting the technical scheme, the strength and the rigidity of the cutter bar are weakened to the minimum, the length of the cutter bar can be set to be the shortest and the diameter of the cutter bar is the largest in terms of material mechanics, the connection rigidity and the reliability of the fly cutter and the cutter bar are greatly improved, the chatter vibration is reduced, and the cutting condition is improved; because the positioning and clamping mechanism is arranged in the central hole, the axial space is not occupied, the problems that the fly cutter and the cutter bar are difficult to manufacture due to the fact that the fly cutter is arranged along the axial direction of the cutter bar are avoided, the rigidity of the cutter bar is poor, the tangential feed time is long, meanwhile, the safety is improved, conditions are created for realizing fly cutter processing of the whole worm gear hob with the handle, and the bottleneck that a multi-head worm gear hob with a small part of working worm diameter is difficult to manufacture is solved.

2. The combination of on-line measurement and adjustment of the thickness of the split washer by means of a measuring device facilitates accurate adjustment of the radial position of the fly cutter extending out of the cutter bar within a certain range, the adjustment precision is high, the fly cutter is high in positioning precision and accurate in positioning, the clamping force is large, self-locking is achieved, the fly cutter is difficult to loosen after clamping, the fly cutter is suitable for powerful cutting, the structure is simple and compact, and the manufacture, the use and the maintenance are convenient.

The fly cutter and the inclined wedge (surface) generate boosting and self-locking effects by the intermittent cutting force, so that the fly cutter wedge is tighter and firmer as the cutting force is larger, the dynamic rigidity between the cutter and the cutter bar is good, the productivity is facilitated, the cutting stability can ensure the roughness of the tooth surface, and under the combined action of the force generated by the force application component and the cutting force, the generated double vertical clamping and double self-locking can obtain better positioning and clamping performance.

3. Because one fly cutter is additionally arranged, manual splitting is not needed, or manual splitting (errors) are reduced, and the fly cutter is used for rough cutting (for example, a chip splitting groove is formed), so that the enveloping (precision) effect and the productivity of the worm gear and the durability of the fly cutter are improved, particularly the durability between two times of regrinding of the fly cutter in the precision cutting process is very important, and the method is particularly critical for a multi-head precision worm gear which is large in modulus and more in tooth number and is made of a hard material.

When one fly cutter is only used as 'invalid envelope cutter tooth', the cutting edges of the fly cutter are provided with chip separating grooves, or the tooth tops of the fly cutters are slightly increased, so that the top edges of the fly cutters of the 'valid envelope cutter tooth' do not participate in cutting, cutting patterns are changed, cutting conditions are improved, the technical scheme of the chip separating grooves and the like is adopted, efficient hobbing with large cutting depth and large tangential feed amount can be achieved, the cutting efficiency, the productivity and the durability of the fly cutter are improved, the final envelope effect of the worm gear tooth surface is unchanged under the condition of the same tangential feed amount, the defect that the 'invalid envelope cutter tooth' only has the cutting function and does not have the envelope function is converted into an advantage, the service life of the fly cutter is prolonged, the 'II' -shaped chips with the worst cutting conditions are eliminated, the durability between two times of regrinding of the fly cutter is further improved, and the cutting edge shape structure and the fly cutter combination form are optimized.

The fly cutter can be further utilized to optimize the process design by the fact that the fly cutter is simple in structure, mostly single-tooth, high-precision, high-performance and high-hardness fly cutter obtains easiness and working conditions, namely, the double fly cutters are provided with fly cutter groups with different cutting performances (such as coarse and fine) and feed (radial and tangential feed) modes, split heads, tooth shapes and the like, the respective advantages of a feeding method, a tooth shape, an optimized edge shape, an optimized cutting angle, a process system and the like are fully exerted to improve the cutting conditions, the optimized cutting amount further improves the productivity and the durability between two times of fly cutters and regrinding, particularly, the radial feeding method is adopted to make up the natural shortage that the tangential feed productivity is not high or the large or variable tangential feed is adopted to obtain higher productivity during rough cutting, the small or variable tangential feed is adopted during fine cutting to improve or optimize the tooth shape precision (contact spots) and the productivity (cutting efficiency), therefore, according to the precision, the working condition and the like required by the worm gear to be cut, the tooth profile precision and the production rate can be improved or optimized by regulating the size of the tangential feeding amount and the feed mode in the gear cutting process, the production rate of the fly cutter hobbing worm gear is improved in the prior art, and the precision is higher than the precision of the worm gear hobbing cutter.

In addition, the effective cutting depth of the concave parts such as the chip dividing grooves is matched with the feed amount and the cutting track of the fly cutter, so that the cutting amount is optimized, and the tooth cutting efficiency and the durability of the fly cutter are improved.

4. The ball and the lubricating wax are adopted to enable all parts to move freely, no blocking exists, the disassembly and the assembly are convenient, the movement is flexible, the structure is simple, the material taking is convenient, the cost is low, and the cutter bar manufacturing and maintenance are simplified.

5. The included angle between the plane for flattening the straight shank of the fly cutter and the rake face with zero rake angle of the fly cutter is irrelevant to the included angle theta of the axial lead of the straight shank of the fly cutter and is also irrelevant to the inclination angle theta of the positioning ejector rod, namely, the principle error of the included angle between the rake face with zero rake angle of the fly cutter and the rotation central line of the cutter rod does not exist.

In a word, the technical scheme has the advantages of simple and compact structure, convenient manufacture, use and maintenance, low cost, free movement of the positioning and clamping mechanism, no principle error (such as an included angle theta), high precision of fly cutter fine adjustment and repeated positioning, large clamping force and difficult loosening, good process system rigidity, the advantages of a radial feeding method, a fly cutter and fly cutters with different cutting performances are fully exerted, powerful, efficient and high-quality cutting with optimized cutting amount is facilitated, particularly, the tooth profile precision (contact spots) and the productivity are improved or optimized by regulating the size of the tangential feeding amount and the feed mode in the tooth cutting process, the durability and the service life of the fly cutter are improved, the method improves the productivity and the tooth form precision of the fly cutter hobbing worm gear in the prior art, has higher precision than the machining precision of a worm gear hobbing cutter, and particularly relates to the hobbing of a multi-head large-modulus small-tooth-number worm gear with smaller diameter and higher precision.

Drawings

FIG. 1 is a schematic view of the clamping of the fly cutter bar of a worm gear with a middle and small module in the prior art

FIG. 2 is a schematic view showing the clamping of a circular arc surface of a cutter bar pull rod of a large-modulus fly cutter in the prior art (r is the radius of a concave circular arc groove of a cylindrical part of the circular pull rod with a screw)

FIG. 3 is a schematic view showing the clamping of the tool bar of the prior art large-modulus fly cutter with the inclined plane (beta is an acute angle of the inclined plane of the cylindrical part of the round pull bar with the screw)

Fig. 4 is a schematic structural diagram of embodiment 1 of the present invention (R is a work worm indexing cylinder radius, m is a work worm axial modulus, an angle between a fly cutter straight shank leveling plane and a fly cutter zero rake face, θ is an angle between the fly cutter straight shank leveling plane and a fly cutter straight shank axial lead, and an inclination angle of a positioning ejector pin end face): the right-handed fly cutter and the fly cutter are arranged in the normal direction, the force application component adopts a screw with a square cylindrical end, the force application component is positioned and connected with the central hole, and the opening direction of the acute angle theta faces to the straight shank of the fly cutter, namely gamma.

Fig. 5 is a structural schematic diagram feature of embodiment 2 of the present invention: the left-handed cutter and the fly cutter are arranged in the normal direction, a force application component adopts a screw with a square cylindrical end, the force application component is positioned and connected with the central hole, and theta is 0 degree and gamma is.

Fig. 6 is a structural schematic diagram feature of embodiment 3 of the present invention: the left or right rotary fly cutter is arranged in the axial direction, the force application component adopts a screw with a square cylindrical end, the force application component is positioned and connected with the central hole, and the opening direction of the acute angle theta faces to the fly cutter head and is equal to 0 degree.

Fig. 7 is a structural schematic diagram feature of embodiment 4 of the present invention: the right-handed fly cutter and the fly cutter are arranged in the normal direction, the force application component adopts an electro-hydraulic push rod or a liquid, pneumatic cylinder and a gas-liquid force enhancing mechanism, the force application component is positioned with the center hole in a sliding mode and is connected with the end face of the driven end of the cutter bar, and the opening direction of the acute angle theta faces to the straight shank of the fly cutter, namely gamma.

Fig. 8 is a structural schematic characteristic of embodiment 5 of the present invention: the right-handed fly cutter and the fly cutter are arranged in the normal direction, the force application component adopts a spring or a spring assembly, the force application component is positioned with the center hole in a sliding mode and is connected with the end face of the driven end of the cutter bar, and the opening direction of the acute angle theta faces to the straight shank of the fly cutter, namely gamma.

Detailed Description

Embodiments

1, 2 and 3

Embodiments

1, 2, and 3 respectively correspond to three clamping structures of a worm-gear fly cutter as shown in fig. 4, 5, and 6, and include a cutter bar 1, where the cutter bar 1 includes a driving end (not shown) with a taper shank and a slender driven end, the driven end is provided with a central hole 4 facing the driving end and concentric with a rotation central line of the cutter bar 1, two parallel mounting holes 2 for mounting a fly cutter straight shank 72 are radially provided along the rotation central line (along an axial direction) of the cutter bar at a proper position in the middle of the cutter bar 1, a center distance between the mounting holes 2 is an axial tooth pitch pi m of a working worm, and a central line of the mounting hole 2 is perpendicular to the rotation central line of the cutter bar 1 and passes through the central hole 4. The cutter bar 1 can be selected from symmetrical section shafts such as a round shaft, a reducer shaft, a polygonal shaft and an inert round shaft so as to be suitable for high-speed roll cutting; the present embodiment takes the through hole as an example.

The further technical scheme is as follows: the mounting hole 2 can be selected from one of a round hole, a square hole, a blind hole and a stepped hole; the round hole can be a cylindrical hole or a square hole or a hexagonal hole, the blind hole can be a cylindrical hole or a square hole, the stepped hole can be a two-section stepped hole or a multi-section stepped hole, and the stepped holes are round holes or square holes and a combination of the round holes and the square holes; the positioning parts of the mounting hole 2 and the fly cutter straight shank 72 are straight holes, so that the fly cutter straight shank 72 is in sliding fit with the inner circumferential surface of the mounting hole 2, and the fly cutter 7 can axially slide and be positioned along the mounting hole 2.

By adopting the technical scheme, when the positioning part of the mounting hole 2 and the fly cutter straight shank 72 is a non-cylindrical hole (such as a square hole), the rotation freedom degree of the fly cutter 7 is limited, and even if the force application member 6 does not apply force, the fly cutter never moves and rotates under the action of cutting force, so that the fly cutter is particularly suitable for rough cutting teeth with large cutting depth and large feed quantity.

The further technical scheme is as follows: in order to ensure that the fly cutter 7 is arranged in the mounting hole 2 and does not move and can axially adjust the size, so as to adjust the radial position of the fly cutter 7 on the cutter bar 1, because a necessary radial clearance exists when the working worm and the worm wheel are meshed, the tooth crest height of the fly cutter is increased by a certain amount compared with that of the working worm, so that the fly cutter 7 is accurate in mounting position and convenient for positioning measurement and repeated positioning, the fly cutter can still be continuously used after sharpening, and a uniform positioning mounting reference is provided, so that the cutting edge parts of two fly cutter heads are positioned at the same part with the working worm and extend out of the cutter bar 1 in the same direction; the size and the shape of the mounting hole 2 are the same, a positioning plane 21 is arranged at the inlet end of a fly cutter straight handle of the mounting hole 2, the distance between the positioning plane 21 and the rotation center line of the cutter rod is consistent, distance size numerical value inscription marks are made, an opening gasket 3 is arranged between the positioning plane 21 and a positioning plane 71 of a worm gear fly cutter head, the positioning plane 21 is perpendicular to the center line of the mounting hole 2, the tooth thickness of the fly cutter is precisely adjusted to be just positioned on an indexing cylinder of a working worm, and the fly cutter is prevented from moving towards the center of the cutter rod 1 after being subjected to cutting force. The positioning plane 21 may be a bottom plane of a counterbore or a groove, or may also be a plane on the periphery of a polygonal shaft, and the counterbore is taken as an example in this embodiment.

By adopting the technical scheme, the flycutters are convenient to exchange, manufacture and install, when the flycutter 7 is installed or the cutting part of the flycutter is abraded and reground, the thickness of the split washer 3 can be changed by a method of changing the thickness of the split washer 3, such as additionally adding a split shim or replacing a thick split washer, and online measurement is carried out by means of a measuring instrument, so that the tooth thickness of the flycutter is conveniently and accurately adjusted to be just positioned on a reference cylinder of a working worm and the flycutter is prevented from moving towards the center of the cutter bar 1 after being subjected to cutting force, the whole flycutter 7 does not need to be taken out of the installation hole 2, the purposes of convenient and rapid adjustment are achieved, the auxiliary time is saved, when the flycutter 7 rotates, the split washer 3 is limited by the positioning plane 21 and the worm wheel flycutter head positioning plane 71, the split washer 3 cannot fly out to hurt people and objects under the action of centrifugal force, and the cutting edge parts of the two fly, therefore, the fly cutter and the cutter bar are properly designed, and conditions are created for using the fly cutter and the cutter bar correctly. The two working planes of the split washer are parallel, but alternatively a non-split flat washer.

The positioning and clamping mechanism 8 is arranged in the central hole 4, a force application member 6, a plurality of round balls 10, a first positioning ejector rod 5A, a first fly cutter 7A and an elastic ejector rod 9 are sequentially and inwardly arranged from a driven end face 11, and penetrate through a hole in a straight shank flattening plane 73 of the first fly cutter 7A, a second positioning ejector rod 5B and a second fly cutter 7B, and the cylindrical end of the elastic ejector rod 9 is inserted into a concentric positioning blind hole 53 in the end face 51 of the opposite end of the first positioning ejector rod 5A. The force application component 6 can be manual force application and mechanical force application, the manual force application needs to work through various force application mechanisms, the manual force application is limited and unstable, when the mechanical clamping is adopted, the original clamping force (acting force) can continuously act, the clamping is reliable, and the mechanism does not need self-locking.

The round ball 10 is a rigid round ball, such as a hardened steel ball, even a steel ball in a waste deep groove ball bearing; the ball 10 is used as part of force transfer medium, the structure is simple, the material is convenient to obtain, the cost is low, the operation is flexible, the rolling friction loss is less, the requirement on a matched hole is low, even the hole which is bent (or a cutter bar is slightly bent) can normally roll, the high requirement on deep hole processing is simplified, if the section of hole is processed by adopting a common twist drill, the manufacturing process and the cutter bar maintenance are simple and convenient.

By adopting the technical scheme, the concentric positioning blind hole 53 is formed in one end face 51 of the first positioning ejector rod 5A, and plays a supporting and positioning role for the elastic ejector rod 9. When the force application member 6 applies force, the end face 51 at the opposite end of the first positioning post rod 5A slides to the fly cutter straight shank leveling plane 73 through the round ball 10 to form close surface contact, the first fly cutter 7A is fastened in the mounting hole 2, meanwhile, the end face 51 at the opposite end of the second positioning post rod 5B slides to the fly cutter straight shank leveling plane 73 to form close surface contact through the elastic post rod 9 of the first fly cutter 7A passing through the hole on the fly cutter straight shank leveling plane 73, and the second fly cutter 7B is fastened in the mounting hole 2. Thus, the first positioning pin 5A can be made short so that it can move more freely in the center hole 4.

The further technical scheme is as follows: the force application member 6 is a screw with a square cylindrical end, and when the screw is tightened, an axial force is generated, and a force application terminal 61 (namely, a cylindrical end) and a threaded part 62 generating the force of the force application member 6 are integrated.

As known to those skilled in the art, when the fly cutter 7 is clamped by an axial force in the central hole 4, because the ball 10 is located between the force application terminal 61 and the first positioning ejector rod 5A, the equivalent friction radius is zero, and the axial (clamping) force generated by the screw is proportional to the acting force and the force arm, inversely proportional to the diameter of the screw, generally tens or even hundreds of times of the acting force, and generates a large clamping force, a large force-increasing effect is achieved. Meanwhile, the included angle theta between the fly cutter straight shank flattening plane 73 and the axial lead of the fly cutter straight shank 72 is small, and the influence on the clamping force in the central hole 4 can be ignored; the force application member 6 uses the force reinforcement and self-locking of the screw, and creates conditions for the fly cutter and the cutter bar to be used correctly.

In order to facilitate free movement, improve precision and facilitate assembly and manufacture, the central hole 4 is a three-section step-shaped hole, namely, a screw hole 42 with a larger diameter is sequentially arranged inwards from the end face 11 close to the driven end of the cutter bar, then a first round unthreaded hole 41A with a smaller diameter and a longer diameter is arranged, the rest is a second round unthreaded hole 41B which is arranged between the two mounting holes 2 and is slightly smaller than the first round unthreaded hole 41A, the first round unthreaded hole 41A and the second round unthreaded hole 41B are respectively and correspondingly provided with a first positioning ejector rod 5A and a second positioning ejector rod 5B which can slide with the inner hole wall, and the first round unthreaded hole 41A is provided with a ball 10 which can slide and roll with the inner hole wall because the ball 10 can freely and flexibly roll in the bent first round unthreaded hole 41A.

The further technical scheme is as follows: the elastic ejector rod 9 is provided with a spherical ball, an adjusting screw and a spring composite assembly, and one end of the elastic ejector rod corresponding to the second positioning ejector rod 5B is a spherical ball.

By adopting the technical scheme, the elastic ejector rod 9 arranged between the first positioning ejector rod 5A and the second positioning ejector rod 5B adjusts the elastic force or compensates the size change of the fly cutter straight shank leveling plane 73 on the cutter bar rotation central line by using the adjusting screw (a method for changing the screw extension length), and the fly cutter straight shank leveling plane is adjusted to a correct position along the axial direction after being abraded and reground, so that the problem that the interference does not occur when two fly cutters 7 are clamped in the central hole 4 is solved, and the clamping force of the two fly cutters 7 tends to be consistent; the ball is provided for realizing that the end faces 51 of the opposite ends of the first positioning mandril 5A and the second positioning mandril 5B simultaneously slide to the fly cutter straight shank leveling plane 73 to form close surface contact, and for ensuring that the elastic mandril 9 flexibly moves and rotates in the central hole 4 and avoids the blocking phenomenon. According to Hooke's law, if the compression quantity is constant, the elastic force is increased by using the change of the length of the spring, and the spring has a buffer effect on the impact force. One end corresponding to the second positioning ejector rod 5B is a round ball, so that the second positioning ejector rod 5B has automatic aligning capability, manufacturing and mounting errors of the elastic ejector rod 9 and the positioning ejector rod 5 are compatible or offset, the service life of the second positioning ejector rod is prolonged, the clamping reliability of the second positioning ejector rod is improved, the equivalent friction radius of the second positioning ejector rod and the end surface (point contact) of the second positioning ejector rod 5B is zero, the transmission efficiency and the flexibility of the positioning ejector rod 5 in rotation in the central hole 41 are improved, and the end surface 51 of the opposite end of the positioning ejector rod 5 can slide to the straight shank planing plane 73 of the fly cutter to form close surface contact. The opposite end surfaces of the spherical balls of the second positioning mandril 5B and the elastic mandril 9 can be straight end surfaces or concave and convex spherical surfaces with the end surfaces, and the radius is larger than that of the spherical balls, so the straight end surfaces are preferred due to simple manufacture and good centering property.

Meanwhile, the round ball is a rigid round ball, such as a hardened steel ball, even a steel ball in a waste deep groove ball bearing; the elastic ejector rod 9 is internally provided with the ball as a part of force transmission medium, has simple structure, convenient material taking, low cost, flexible work, less rolling friction loss, low requirement on a hole matched with the elastic ejector rod, even normal rolling in a bent hole, simple and convenient manufacturing process and is beneficial to the movement of an adjusting screw and a spring.

The elastic ejector rod 9 solves the problems of over-positioning and no interference when clamping by using a spring and an adjusting screw, and enables the clamping force of the two fly cutters 7 to be consistent, and the round ball solves the problem of working flexibility, so that the fly cutters and the cutter bar are properly designed, and conditions are created for correct use.

The further technical scheme is as follows: the threaded portion 62 of the force application member 6 with the square cylindrical end screw is positioned and connected with the threaded hole 42 of the central hole 4.

The further technical scheme is as follows: the thread of the threaded bore 42 (inlet end of the central bore 4) may be selected to be a single or single fine thread, preferably a single fine thread, since a fine thread has a better boosting and self-locking effect than a coarse thread. The common threads comprise coarse threads, threads and ultrafine threads; trapezoidal threads are divided into single and multiple start threads, where single start threads of the same nominal diameter have one or more thread pitches, etc.

The further technical scheme is as follows: the screw thread of the screw hole 42 (the inlet end of the central hole 4) is optionally one of a rectangular screw thread, a trapezoidal screw thread, a common screw thread, and a rectangular screw thread.

The further technical scheme is as follows: one of the following lubricants, namely lubricating wax, calcium-based grease, molybdenum disulfide or thin oil, is selected for the positioning and clamping mechanism 8, and the lubricating wax is convenient to use, less in pollution, safe, harmless and long in service time, so that oil materials are prevented from being dried up or not lubricated, particularly the oil materials are prevented from being bonded, and the lubricating wax is selected as the lubricating wax.

By adopting the technical scheme, under the same condition, the friction force is reduced, the movement is flexible, the assembly and disassembly are convenient, the transmission efficiency and the force increasing effect are improved, and the rust prevention is realized.

The further technical scheme is as follows: in order to facilitate the processing inspection or the trimming of the cutter bar 1, a concentric thimble hole 43 is arranged at the inlet end of the central hole 4, and the concentric thimble hole 43 is a 60-degree taper hole.

The further technical scheme is as follows: the end face of the force application terminal (namely, the cylindrical end) 61 with the square cylindrical end screw (force application member) 6 is a straight end face and is hardened, and the ball 10 is arranged between the end face and the first positioning ejector rod 5A, so that the end face has the automatic aligning capability, the manufacturing and mounting errors of the screw hole 42 and the first positioning ejector rod 5A are compatible or offset, and the mounting precision, the service life and the clamping reliability are improved; and the equivalent friction radius between the force application terminal 61 and the end surface of the first positioning ejector rod 5A and the ball 10 (point contact) is zero, so that the force application ratio and efficiency of the screw 6 with the square cylindrical end are improved, and the first positioning ejector rod 5A can flexibly rotate in the central hole 41A, so that the end surface 51 of the opposite end of the first positioning ejector rod 5A can conveniently slide to the plane 73 of the straight shank of the fly cutter to form close surface contact. The opposite end surfaces of the force application terminal 61 and the first positioning top rod 5A and the round ball 10 can be straight end surfaces or end surfaces which are concave and convex spherical surfaces and have the radius larger than that of the round ball 10, and the straight end surfaces are preferred due to simple manufacture and good centering property.

When the opening direction of the acute angle θ is directed to the fly cutter head 74, the fly cutter 7 generates a component force directed to the fly cutter head 74 under the action of an axial clamping force (force application member 6) along the cutter bar 1, and a cutting force directed to the center of the cutter bar 1 is always generated during cutting, at this time, the intermittent cutting force causes the fly cutter 7 and the wedge (surface) to generate a force-increasing and self-locking effect, and the intermittent cutting force directly impacts the positioning and clamping mechanism 8, so that the clamping effect of the positioning and clamping mechanism 8 is poor; when the opening direction of the acute angle theta faces to the fly cutter straight shank 72, the force application component 6 generates a component force on the fly cutter 7, which is back to the fly cutter head 74, and at the moment, the intermittent cutting force does not form a wedge between the fly cutter 7 and the inclined plane, and does not generate a boosting effect and a self-locking effect, so the intermittent cutting force does not generate direct impact on the positioning and clamping mechanism 8; when the included angle theta between the straight shank planing plane 73 and the axial line of the straight shank 72 is 0 deg., no inclined plane structure exists, so that no wedge boosting and self-locking condition exists, and the force applying member 6 does not generate component force to the fly cutter 7 to the back or the direction of the fly cutter head 74, and the intermittent cutting force does not directly impact the positioning and clamping mechanism 8. Under the action of cutting force always towards the center of the cutter rod 1, the fly cutter 7 tends to move towards the center of the cutter rod 1, the fly cutter head positioning plane 71 further compacts the split washer 3 on the positioning plane 21, and online measurement is carried out by means of a precision measuring instrument, so that repeated positioning and position precision of the double-worm fly cutter 7 are improved, and the fly cutter 7 cannot move and rotate. In particular, the fly cutter 7 and the wedge (surface) generate boosting and self-locking effects by intermittent cutting force, so that the fly cutter is more tightly and firmly wedged as the cutting force is larger, the dynamic rigidity between the cutter and the cutter rod is better, and under the combined action of the force generated by the force application member 6 and the cutting force, double vertical clamping and double self-locking are generated, so that better positioning and clamping performance can be obtained, and the fly cutter is a preferred embodiment.

When the screw (force application member) 6 with the square cylindrical end is screwed, the cylindrical end 61 with the screw moves axially together to generate force, the first positioning ejector rod 5A moves axially through the spherical ball 10, meanwhile, the spring of the elastic ejector rod 9 is stressed and compressed to generate axial force, so that the second positioning ejector rod 5B moves axially, the end faces 51 of the opposite ends of the first positioning ejector rod 5A and the second positioning ejector rod 5B slide to the straight shank flat cutting plane 73 of the fly cutter simultaneously to form close surface contact, and meanwhile, the first fly cutter 7A and the second fly cutter 7B are fastened in the corresponding mounting holes 2.

The further technical scheme is as follows: because of the difference of cutting force and cutter arbor diameter, the convenience of the different and manufacturing of material intensity and precision has better clamping effect and economic nature for guaranteeing. The included angle between the fly cutter straight shank flattening plane 73 and the axial lead of the fly cutter straight shank 72 is an acute angle theta or 0 degree.

Meanwhile, in order to make the end faces 51 of the opposite ends of the first positioning mandril 5A and the second positioning mandril 5B slide to the straight shank flat-cutting plane 73 of the fly cutter simultaneously to form close surface contact so as to ensure reliable clamping and accurate positioning of the fly cutter, the inclination angles of the end faces 51 of the opposite ends of the first positioning mandril 5A and the second positioning mandril 5B are theta or 0 degrees correspondingly according to the straight shank flat-cutting plane of the fly cutter, namely the inclination angles of the end faces 51 of the opposite ends of the first positioning mandril 5A and the second positioning mandril 5B are consistent with the angle of the straight shank flat-cutting plane 73 of the fly cutter.

1. When the cutting force is small, the included angle between the fly cutter straight shank flattening plane 73 and the axial line of the fly cutter straight shank 72 is 0 degree (see embodiment 2 and fig. 5).

2. When the cutting force is larger, the included angle between the fly cutter straight shank flattening plane 73 and the axial line of the fly cutter straight shank 72 is an acute angle theta, and the opening direction of the acute angle theta can be selected to be towards the fly cutter straight shank 72 or the cutter head 74 (see embodiments 1 and 3, and fig. 4 and 6).

When the opening direction of the acute angle theta is towards the fly cutter straight shank 72, under the action of the clamping force and the cutting force along the axial direction of the cutter bar 1, the fly cutter 7 tends to move towards the center of the cutter bar 1, the fly cutter head positioning plane 71 further compacts the opening gasket 3 on the positioning plane 21, so that the repeated positioning precision is improved, and the fly cutter 7 cannot move and rotate (see embodiment 1 and fig. 4).

When the opening direction of the acute angle θ faces the fly cutter head 74, the fly cutter 7 is forced to move toward the center of the cutter bar 1 by the clamping force in the axial direction of the cutter bar 1, and the fly cutter 7 is forced to move toward the center of the cutter bar 1 by the cutting force toward the center of the cutter bar 1, so that the fly cutter head positioning plane 71 further compacts the opening washer 3 on the positioning plane 21 to improve the repeated positioning accuracy, and the fly cutter 7 does not move or rotate (see embodiment 3 and fig. 6).

When the acute angle θ is 0 ° (i.e., the included angle is 0 °), under the action of the clamping force in the axial direction of the tool holder 1, no force is generated to move the fly cutter 7 away from or toward the center of the tool holder 1, and under the action of the cutting force toward the center of the tool holder 1, the fly cutter 7 tends to move toward the center of the tool holder 1, so that the fly cutter head positioning plane 71 further compacts the split washer 3 on the positioning plane 21, and the fly cutter 7 does not move or rotate (see embodiment 2 and fig. 5).

The included angle between the fly cutter straight shank flattening plane 73 and the axial line of the fly cutter straight shank 72 is an acute angle theta or 0 degree, and the fly cutter cannot move and rotate no matter which direction the opening of the acute angle theta faces or is 0 degree because the acute angle theta is smaller, so that the working condition requirement can be met.

An important characteristic of the ramp structure is the clamping travel (i.e. the axial displacement in the central bore 4) and the corresponding distance of displacement of the fly cutter 7 in its axial direction, the acute angle theta being reduced, the sensitivity of the fly cutter 7 to displacement in its axial direction is increased, which is advantageous for regrinding the fly cutter 7 after wear, but is disadvantageous for adjusting the axial positioning accuracy, for which reason the acute angle theta should not be chosen too small. Obviously, when the included angle theta is 0 degree, the fly cutter is reground after being worn,

the further technical scheme is as follows: the value range of the acute angle theta is between 3 degrees and 6 degrees.

Still further technical scheme is: for the convenience of adjustment and axial positioning accuracy after regrinding of the fly cutter 7, the acute angle θ is selected to be 4.5 °.

The further technical scheme is as follows: in order to facilitate the flexible and free movement and rotation of the positioning post rod 5 along the circular unthreaded hole 41, in order to reduce the contact area between the positioning post rod 5 and the circular unthreaded hole 41 and accommodate lubricant and sundries, the circumferential surface of the positioning mandril 5 or the circular hole 41 can be provided with a plurality of sections of circular grooves with guide angles, and in order to facilitate processing, preferably, the circumferential surfaces of the first positioning mandril 5A and the second positioning mandril 5B are provided with a plurality of sections of circular grooves 52 with guide angles, and the circular ring-shaped groove 52 is arranged at the two ends of the first positioning mandril 5A and the second positioning mandril 5B, thus, when the positioning ejector rod 5 is assembled and disassembled and has slight bending or long-term extrusion deformation of two ends, the positioning ejector rod can easily pass through the part, and in order to improve the service life of the positioning ejector rod 5 and ensure the clamping reliability, the two end faces of the first positioning ejector rod 5A and the second positioning ejector rod 5B are hardened.

The front angle of a common fly cutter is 0 degrees, at the moment, the fly cutter front cutter face 75 is coincided with the axial lead of the fly cutter straight handle 72, a positive front angle is selected for improving the productivity or hobbing high polymer materials (such as MC nylon), the front cutter face when the fly cutter front angle is not equal to 0 degrees is projected onto the fly cutter front cutter face 75 with the front angle of 0 degrees or the front angle of the front cutter face 75 is 0 degrees, and the fly cutter front cutter face 75 is called as a fly cutter zero front angle front cutter face 75; the reasonable selection and the sharpening of the front and back angles of the fly cutter can obviously improve the cutting performance and the durability and the productivity of the cutter, and the roughness of the tooth surface and the consumed power are smaller; when the fly cutter 7 is clamped on the cutter bar 1, the fly cutter zero rake face 75 is just in the normal direction or axial plane of the working worm, i.e. the included angle between the fly cutter zero rake face 75 and the rotation center line of the cutter bar 1 is gamma or coincident (i.e. the included angle is 0 °), so that the cutting edge part of the fly cutter head 74 is in the same position as the working worm.

The further technical scheme is as follows: the included angle between the fly cutter straight shank flattening plane 73 and the fly cutter zero rake angle rake face 75 is determined according to the type and precision grade of the working worm, the size and the rotary direction of the indexing cylindrical lead angle of the working worm when the fly cutter 7 is tightly clamped on the cutter bar 1, so that the fly cutter zero rake angle rake face 75 is just positioned on the normal direction or the axial plane of the working worm, namely gamma or 0 deg.

1. If the Archimedes or normal straight profile worm wheel with a larger indexing cylindrical lead angle gamma of the working worm is hobbing, the included angle between the fly cutter straight shank planing plane 73 and the fly cutter zero front angle front cutter surface 75 is equal to the indexing cylindrical lead angle gamma of the working worm, the fly cutter zero front angle front cutter surface 75 is just positioned in the normal plane of the working worm, and the fly cutter zero front angle front cutter surface 75 is clamped in a normal direction, so that both side blades have reasonable front angles (0 DEG front angle or positive front angle) and back angles, the cutting condition can be improved, and the quality and the work efficiency can be improved. When rotating rightly, see embodiment 1 and attached figure 4; when rotating left, see example 2, fig. 5.

2. When rolling and cutting a normal straight-profile worm gear with a small indexing cylindrical lead angle gamma of the working worm and low precision requirements, the included angle between the fly cutter straight shank flattening plane 73 and the fly cutter zero front angle front cutter face 75 is equal to 0 degrees, the fly cutter zero front angle front cutter face 75 is just positioned in the axial plane of the working worm, and the fly cutter zero front angle front cutter face 75 is axially clamped, so that the cutting angles of cutting edges on two sides are different, such as a sharp edge is a positive front angle, a blunt edge is a negative front angle and the like, so that the cutting conditions are inconsistent, the tooth surface of the processed worm gear is easy to generate ripples, the improvement of the productivity is limited, the performances of a machine tool and a cutter cannot be fully exerted, and the like; in order to improve the cutting conditions, the front cutter face can be ground by adopting a special edge grinding method, so that the cutting edges on both sides of the fly cutter have proper rake angles. See example 3, FIG. 6.

By adopting the technical scheme, the included angle between the fly cutter straight shank flattening plane 73 and the fly cutter zero-front-angle front cutter face 75 is irrelevant to the included angle theta between the axial lead of the fly cutter straight shank 72, the accuracy of the contact surface between the end surface 51 at the opposite end of the positioning ejector rod and the fly cutter straight shank flattening plane 73 is only influenced, namely the influence of the machining error of the theta angle on the opposite angle is avoided, so that the principle error of the included angle between the fly cutter zero-front-angle front cutter face 75 and the rotating central line of the cutter bar 1 is avoided, the azimuth angle (included angle) of the fly cutter zero-front-angle front cutter face 75 on the cutter bar 1 is one of the conditions that the fly cutter is used correctly, the fly cutter and the cutter bar are designed properly, the conditions are created for using correctly, and the prior art is relevant to the inclination angle beta of the bevel plane arranged on the cylindrical part of the round.

The elastic mandril 9 is used for solving the interference problem of clamping two fly cutters 7 by utilizing the force application (increasing) force and self-locking of a screw (force application component) 6 with a square cylindrical end, and the positioning, clamping and self-locking are simultaneously realized by the measures; the requirements that the two fly cutters 7 are reliably clamped after being arranged in the cutter bar 1, and do not move or rotate during cutting are fully met, and the connecting rigidity and reliability are higher; is a common and reliable force-increasing self-locking mechanism.

The invention does not relate to other parts of the cutter bar and is arranged conventionally; because the invention avoids the influence of the angle theta on the opposite angle from the design, the ordinary technicians in the field can change the fly cutter adaptively, for example, a waist-shaped hole is arranged on the first fly cutter 7A straight shank leveling plane 73 along the axial direction of the fly cutter, the edges at the two sides of the fly cutter are symmetrical to the axis of the fly cutter straight shank 72, and other fly cutters are arranged conventionally.

It is pointed out that the rake face of the tooth (fly cutter) of the worm gear cutter with a handle is directional, and the driving end with a taper handle is fixed at one end of the cutter, while the hobbing movement relation of the specific machine tool is not changed, and the sleeve worm gear cutter can be turned and installed in the cutter bar to change, which is fundamentally different from the sleeve worm gear cutter.

The clamping working procedure of the fly cutter is as follows:

1) according to the distance from the tooth thickness position of the fly cutter on the working worm indexing cylinder to the fly cutter head positioning plane 71 and the distance from the positioning plane 21 to the cutter bar rotation central line, selecting an opening gasket 3 with proper thickness to be installed in a fly cutter straight handle 72, sequentially placing positioning clamping parts in a central hole 4, and respectively and correspondingly inserting the fly cutter straight handle 72 into an installation hole 2 from one side engraved with an azimuth mark, so that the two fly cutter cutting edge parts extend out of the cutter bar in the same direction, and enabling a fly cutter zero front angle front cutter face 75 to face the rotation direction of the fly cutter during working;

2) at the moment, the fly cutter straight shank flattening plane 73 faces the cutter bar passive end face 11, tight surface contact is formed between the fly cutter head positioning plane 71 and the opening gasket 3 and the positioning plane 21, and the clamping mechanism 8 applies force properly;

3) by means of on-line measurement of a measuring instrument, when the thickness of the flywheel tooth is just on the indexing cylinder of the working worm, the flywheel tooth is firmly clamped by the clamping mechanism 8;

4) when the fly cutter is replaced or the roller cutting is worn and reground after a period of time, the working process is repeated.

In the above working process, the correct position of the tooth thickness of the two fly cutters 7 on the working worm indexing cylinder in the radial direction of the cutter bar 1 and the orientation of the fly cutter zero rake face 75 are respectively determined.

Embodiment 4

Fig. 7 reflects the specific structure of another embodiment of the present invention, which is different from the above-mentioned embodiment, mainly the force applying member 6 is an electro-hydraulic push rod or hydraulic, pneumatic cylinder, and air-liquid force increasing mechanism, and is positioned and connected with the tool bar 1; specifically, the larger diameter part of the central hole 4 (inlet end) is a round smooth hole 42 to facilitate the sliding positioning of the force application member 6, and the end face 11 of the passive end is provided with a plurality of screw holes connected with the force application member 6.

The further technical scheme is as follows: the force application member 6 adopts an electro-hydraulic push rod or a hydraulic, pneumatic cylinder and a gas-liquid force increasing mechanism, the axial force is generated by using liquid, air pressure or electricity as energy, a piston rod of the hydraulic cylinder or the pneumatic cylinder is used as a force application terminal 61, an interface 63 connected with electricity, liquid and gas is arranged on the rotation center line of the force application member 6, and the interface 63 connected with electricity, liquid and gas is a rotary joint.

When the hydraulic, pneumatic or electro-hydraulic push rod works, the force application terminal 61 moves axially to generate an axial force, the inclined end faces 51 of the opposite ends of the first positioning ejector rod and the second positioning ejector rod slide to the inclined cutting flat plane 73 of the straight shank of the fly cutter simultaneously through the plurality of round balls 10 to form close surface contact, and the two fly cutters 7 are fastened in the corresponding mounting holes 2 and are located at correct positions.

The further technical scheme is as follows: the force application member 6 is positioned in a sliding manner with the central hole 4 and is connected with the cutter bar passive end surface 11.

Embodiment 5

Fig. 8 reflects a specific structure of a further embodiment of the present invention, which differs from example 4 in that the force application member 6 is a spring or a spring assembly, and in that fig. 8 shows a disc spring and a leveling washer in the central hole 4.

The further technical scheme is as follows: the force application component 6 is a spring or a spring assembly, the spring is uniformly and elastically deformed after being stressed and compressed, the elastic force generates axial force to push the force application terminal 61 to move axially, and the elastic force is adjusted by using an adjusting flat washer or a screw.

When the spring is stressed and compressed, the spring is elastically deformed uniformly, the force application terminal 61 moves axially to generate an axial force, the oblique end faces 51 of the opposite ends of the first positioning ejector rod and the second positioning ejector rod slide to the oblique flat plane 73 of the straight shank of the fly cutter simultaneously through the plurality of balls 10 to form close surface contact, and the two fly cutters 7 are fastened in the corresponding mounting holes 2 and are located at correct positions.

The leveling washer may be provided between the biasing member 6 and the holder passive end surface 11 (not shown). In order to facilitate the screwing of the screw to generate a compression force on the spring, the screw is provided on the center line of the biasing member 6 and the holder passive end surface 11 (not shown).

The difference between the cutting force and the diameter of the cutter bar can be comprehensively considered, the material strength, the working worm type, the lead angle and the precision of the indexing cylinder of the working worm are different, and the manufacturing convenience is realized, and in order to ensure better clamping and self-locking effects and economy, the cutting tool can be selected or combined in the 5 embodiments.

The included angle between the plane for flattening the straight shank of the fly cutter and the axial lead of the straight shank of the fly cutter is an acute angle theta or 0 DEG, the force application component and the opening gasket are combined to be adjusted, clamped and self-locked, and the online measurement is carried out by means of a measuring instrument, and the acute angle theta is small, so that the fly cutter cannot move or rotate no matter which direction the opening of the acute angle theta faces or is 0 DEG or no matter how large the external (resistance) force is, even if the force application and the self-locking of the wedge are not carried out, and the fly cutter is ensured to be in a correct position so as to meet the requirements of working conditions.

The flying cutter and the cutter bar are properly designed and correctly used by combining the prior manufacturing technology, the flying cutter is simple in structure and mostly has single teeth, the manufacturing and sharpening detection are more convenient, the flying cutter with high precision, high performance and high hardness is easier to obtain than a worm hob, the number of broken line segments enveloping the tooth form of the worm gear is inversely proportional to the tangential feed amount, and the production rate is directly proportional to the broken line segments, so the tooth form precision (contact spots) can be artificially controlled in the tooth cutting process, the production rate is improved in the prior art, the precision is higher than that of the worm hob, and particularly, the worm gear with small diameter, high precision, multiple heads, large modulus and small tooth number has more advantages in the hobbing work.

However, it should be understood by those skilled in the art that the force applying member 6 is not limited to the specific structure shown in fig. 4 to 8, for example, the spring may be a truncated cone helical compression spring or a truncated cone spiral spring, even a rubber spring, etc., and furthermore, the central hole 4 is not limited to being formed as a circular hole and a hole with three steps, but may also be formed as a square hole, such as a square hole, or a hole with two steps, etc., in which case, of course, the shapes of the positioning push rod 5 and the force applying member 6 are modified or changed accordingly, and the positioning and the connection manner of the force applying member 6 are changed adaptively.

The preferred embodiments of the present invention have been described in detail with reference to the accompanying drawings, but the present invention is not limited to the details of the above embodiments, and various simple modifications can be made to the technical solution of the present invention within the technical idea of the present invention, and these simple modifications fall within the scope of the present invention. If a measuring method is adopted to determine the distance from the top edge of the fly cutter 7 to the excircle of the cutter bar 1, the split washer 3 is not required to be arranged, or the positioning plane 21 is not required to be arranged; in another example, to reduce the number of the cutter bars, more than two mounting holes 2 may be installed, but only two fly cutters 7 are installed, or the center distance of adjacent mounting holes 2 is not equal to the integral multiple of 1 of the axial pitch of the working worm, and in addition, even only one fly cutter is installed and the opening direction of the acute angle θ of the fly cutter used at the same time is opposite, and the like, which does not affect the achievement of the object of the present invention.

It should be noted that the technical features described in the above embodiments may be combined in any suitable manner without contradiction. The invention is not described in detail in order to avoid unnecessary repetition.

The above-mentioned embodiments are provided for illustrative purposes only and not for limiting the present invention, and those skilled in the art can make various changes and modifications without departing from the spirit and scope of the present invention, so that all equivalent technical solutions should fall within the scope of the present invention, and the scope of the present invention should be limited by the claims.

Claims

1. The utility model provides a tight structure of clamp of two worm wheel fly sword, includes cutter arbor (1), its characterized in that cutter arbor (1) comprises the initiative end and the slender passive end of taking the taper shank, passive end is equipped with towards the initiative end and with concentric centre bore (4) of cutter arbor (1) rotation center line, radially is equipped with two parallel mounting holes (2) of installation fly sword at cutter arbor (1) middle part along cutter arbor rotation center line, centre-to-centre spacing between mounting hole (2) is the axial tooth distance pi m of a work worm, the perpendicular just cutter arbor (1) rotation center line of crossing of centre line of mounting hole (2), and with centre bore (4) link up, and location clamping mechanism (8) are established in centre bore (4), inwards be equipped with application of force component (6), a plurality of ball (10), first location ejector pin (5A) in proper order from passive end terminal surface (11), A first fly cutter (7A), an elastic ejector rod (9), a second positioning ejector rod (5B) and a second fly cutter (7B), and the cylindrical surface end of the elastic ejector rod (9) is inserted into a concentric positioning blind hole (53) of the end surface (51) of the opposite end of the first positioning ejector rod (5A), the force application component (6) generates axial force to enable the end surfaces (51) of the opposite ends of the first positioning mandril (5A) and the second positioning mandril (5B) to simultaneously slide to the straight shank planishing plane (73) of the fly cutter to form close surface contact, the two fly cutters (7) are fastened in the corresponding mounting holes (2), the cutting edge parts of the two fly cutter heads (74) are positioned at the same part with the working worm, the direction of the fly cutter extending out of the cutter rod (1) is the same as the rotation direction of the fly cutter when the fly cutter works, namely the rake face (75) with zero front angle faces.

2. The clamping structure of the double worm-gear fly cutter as claimed in claim 1, wherein the mounting hole (2) is selected from one of a round hole, a square hole, a blind hole and a stepped hole, and the positioning parts of the mounting hole (2) and the fly cutter straight shank (72) are straight holes.

3. The clamping structure of the double-worm-gear fly cutter as claimed in claim 1 or 2, wherein the mounting holes (2) are identical in size and shape, a positioning plane (21) is arranged at the straight shank inlet end of the fly cutter of the mounting hole (2), the distance between the positioning plane (21) and the rotation center line of the cutter bar is consistent, and a distance size numerical value is marked, an opening gasket (3) is arranged between the positioning plane (21) and the positioning plane (71) of the head of the worm gear fly cutter, and the positioning plane (21) is perpendicular to the center line of the mounting hole (2).

4. The clamping structure of a twin worm gear fly cutter as claimed in claim 1, wherein the force application member (6) is one of a screw with a square cylindrical end, the axial force is generated when the screw is tightened, and the force application terminal (61) of the force application member (6) and the force generation threaded portion (62) of the force application member (6) are integrated; the force application component (6) adopts an electro-hydraulic push rod or a hydraulic, pneumatic cylinder and a gas-liquid force increasing mechanism, liquid, air pressure or electricity is used as energy to generate axial force, a piston rod of the hydraulic cylinder or the pneumatic cylinder is used as a force application terminal (61), and an interface (63) connected with electricity, liquid and gas is arranged on the rotation center line of the force application component (6); the force application component (6) adopts a spring or a spring assembly, the spring is uniformly and elastically deformed after being stressed and compressed, the elastic force generates axial force to push the force application terminal (61) to axially move, and the elastic force is adjusted by using an adjusting flat washer or a screw.

5. The clamping structure of the twin worm gear fly cutter according to claim 1, wherein the elastic carrier rod (9) is provided with a composite assembly of a ball, an adjusting screw and a spring, and one end corresponding to the second positioning carrier rod (5B) is a ball.

6. The clamping structure of a double worm-gear fly cutter as claimed in claim 1, wherein the force applying member (6) is positioned and connected with the central hole (4), or the force applying member (6) is positioned and connected with the central hole (4) in a sliding manner and connected with the cutter bar passive end face (11).

7. The clamping structure of a twin worm-gear fly cutter as claimed in claim 1, wherein the end face of the force application terminal (61) of the force application member (6) is a straight end face and is hardened.

8. The clamping structure of the twin worm gear fly cutter according to claim 1, wherein the included angle between the fly cutter straight shank flattening plane (73) and the axis line of the fly cutter straight shank (72) is an acute angle θ or 0 °, and the inclination angle of the end faces (51) of the opposite ends of the first positioning ejector pin (5A) and the second positioning ejector pin (5B) is θ or 0 ° correspondingly.

9. The clamping structure of the twin worm-gear fly cutter as claimed in claim 8, wherein the acute angle θ is in a range of 3 ° to 6 °, and the acute angle θ is 4.5 °.

10. The clamping structure of a twin worm gear fly cutter as claimed in claim 1, wherein the included angle between the fly cutter straight shank planing plane (73) and the fly cutter zero rake face (75) is equal to the work worm indexing cylindrical lead angle γ, or is 0 °.