Inward milling processing device

Abstract

The application discloses an internal rotary milling device, which comprises a rack, an electric spindle for driving the rotation of a workpiece, the electric spindle being installed on the rack and comprising a shaft core and a front bearing assembly installed at one end of the shaft core, a rotary milling mechanism installed on the rack, and a floating tailstock abutting against one end of the workpiece, the floating tailstock comprising a floating seat and a center bit assembly; wherein the rotary milling mechanism is arranged between the electric spindle and the floating tailstock, and the center bit assembly can be driven to displace relative to the floating seat when the workpiece acts on the center bit assembly; the shaft core comprises an integral blocking portion extending radially from the end, and the blocking portion abuts against one side of the front bearing assembly. The floating tailstock structure and the connecting structure between the shaft core and the front bearing assembly on the electric spindle improve the axial bearing and floating adjustment capacity, and increase the service life of the device.

Description

TECHNICAL FIELD

[0001] The present application relates to the technical field of machine tools, in particular to an internal rotary milling device. BACKGROUND

[0002] Internal rotary milling processing belongs to a kind of rotary milling, mainly used for long workpiece thread processing, which rotates cutterhead by motor drive, and the workpiece is placed in the processing hole of cutterhead, and the cutter is installed on the inner wall of cutterhead, and the cutter is driven by cutterhead to mill workpiece during rotation.

[0003] When the internal rotary milling device processes the workpiece, the workpiece will be subjected to axial force from the cutter milling, and the workpiece will transmit the axial force to the spindle and tailstock. The existing workpiece generally adopts rigid clamping positioning, so that mutual extrusion force will be generated between parts. After long-term use, the equipment needs to be maintained and repaired. Combined with the thermal expansion of the workpiece during processing, the extrusion wear of the parts will be aggravated and the service life will be reduced. SUMMARY

[0004] In order to improve the service life of the equipment, the present application provides an internal rotary milling device.

[0005] The internal rotary milling device provided by the present application adopts the following technical scheme:

[0006] An internal rotary milling device comprises:

[0007] A rack;

[0008] An electric spindle for driving the rotation of the workpiece, the electric spindle is installed on the rack, comprising a shaft core and a front bearing assembly installed at one end of the shaft core;

[0009] A rotary milling mechanism installed on the rack; and

[0010] A floating tailstock abutting against one end of the workpiece, the floating tailstock comprising a floating seat and a center point assembly;

[0011] Wherein, the rotary milling mechanism is arranged between the electric spindle and the floating tailstock, and when the workpiece acts on the center point assembly, the center point assembly can be driven to displace relative to the floating seat, the shaft core comprises an integral stop portion extending radially from the end, and the stop portion abuts against one side of the front bearing assembly.

[0012] By adopting the above technical scheme, when the workpiece is subjected to thread processing by the rotary milling mechanism, the axial force borne by the workpiece in combination with the thermal expansion coefficient of the workpiece itself causes the shaft core and the center component to bear the axial force from the workpiece. When the axial force acts on one side of the electric spindle, the shaft core has the radially extending blocking portion, which replaces the locking nut on one side and abuts against the front bearing assembly, thereby increasing the contact area and being capable of sharing the axial load. Meanwhile, the integral blocking portion reduces the axial displacement between the locking nut and the shaft core when the locking nut limits the front bearing assembly, thereby reducing the wear of the screw thread of the locking nut after a long time, improving the limiting stability of the front end of the front bearing assembly, and prolonging the service life. In addition, when the axial force acts on the floating tailstock, the floating structure of the center component can further reduce the extrusion wear between the workpiece and the center component, thereby prolonging the service life of the equipment.

[0013] Preferably, the front bearing assembly comprises:

[0014] a front bearing seat;

[0015] a plurality of adjacent front bearings mounted on the shaft core and arranged in the front bearing seat;

[0016] a first front blocking ring mounted on the shaft core and abutting against the inner ring of one side of the front bearing;

[0017] a front end cover connected with the front bearing seat, the front end cover having an inner ring connected with the first front blocking ring, the inner ring abutting against the outer ring of one side of the front bearing;

[0018] a first rear blocking ring mounted on the shaft core and abutting against the end face of the other side of the front bearing; and

[0019] a first locking nut threadedly connected with the shaft core and abutting against the first rear blocking ring.

[0020] The blocking portion abuts against the first front blocking ring and / or the inner ring.

[0021] By adopting the above technical scheme, the front bearing assembly can stabilize the rotation of the shaft core during the rotation. The first front blocking ring and the first rear blocking ring limit the left and right displacement of the front bearings, respectively. The first locking nut limits the axial displacement of one side of the first rear blocking ring. The front end cover, in combination with the first front blocking ring, limits the axial displacement of the inner ring and the outer ring of the front bearing, and increases the contact area between the blocking portion, so that the axial load transmitted from the workpiece to the shaft core can be better shared, thereby prolonging the service life of the components.

[0022] Preferably, the electric spindle further comprises:

[0023] a rotor having a through mounting hole in the rotor;

[0024] A clamping sleeve is arranged on the outer circumferential wall of the shaft core and passes through the mounting hole, the clamping sleeve can rotate synchronously with the shaft core, and the two ends of the clamping sleeve extend out of the mounting hole; and

[0025] A locking ring is arranged at the two ends of the rotor, and the locking ring is connected with the rotor through a fastener;

[0026] The clamping sleeve comprises a main body part and an extension part connected to the two ends of the main body part, the outer circumferential surface of the extension part is a first tapered surface, the locking ring has an inner hole, the inner circumferential surface of the inner hole is a second tapered surface, and the extension part enters the inner hole and the first tapered surface and the second tapered surface abut against each other.

[0027] By adopting the above technical scheme, the clamping sleeve is connected with the shaft core, the rotor is connected through the locking ring and the fastener, and the connection of the rotor, the clamping sleeve and the shaft core is realized, the quick disassembly and assembly of the rotor can be realized on the connection structure, and the process disassembly and assembly of the rotor and the shaft core through thermal expansion and cold shrink is more convenient. Secondly, when the locking ring is connected with the clamping sleeve, the first and second tapered surfaces abut against each other, when the shaft core is subjected to an axial force, the connection strength between the locking ring and the clamping sleeve can be increased, and the rotation of the rotor is more stable.

[0028] Preferably, the electric spindle further comprises a rear bearing assembly, the rear bearing assembly comprising:

[0029] A rear bearing seat;

[0030] A plurality of adjacent rear bearings are installed on the shaft core and arranged in the rear bearing seat;

[0031] A second front retainer ring is installed on the shaft core and abuts against the end surface of one side rear bearing;

[0032] A second rear retainer ring is installed on the shaft core and abuts against the end surface of the other side rear bearing; and

[0033] A second locking nut is threadedly connected with the shaft core and abuts against the second rear retainer ring.

[0034] By adopting the above technical scheme, the rear bearing assembly can stabilize the support effect of the rear end when the shaft core rotates, the second front retainer ring and the second rear retainer ring limit the axial position of the plurality of rear bearings on the left and right sides respectively, and the second locking nut axially limits the second rear retainer ring.

[0035] Preferably, the center tip assembly comprises:

[0036] A top rod is slidingly connected in the floating seat;

[0037] A piston is connected to the top rod;

[0038] A rotary center tip is rotationally connected to one end of the top rod; and

[0039] a cylinder connected to the other end of the ejector rod for driving the ejector rod to displace relative to the floating seat;

[0040] The floating seat has an outer chamber and an inner chamber, the outer chamber and the inner chamber contain hydraulic oil, the piston is connected to the inner chamber and separates the inner chamber into an upper chamber and a lower chamber, the floating seat is provided with a guide valve for connecting the outer chamber and the upper chamber and a compression valve for connecting the outer chamber and the lower chamber.

[0041] By using the above technical scheme, when the floating tail seat is in contact with the workpiece, the cylinder drives the ejector rod to axially displace relative to the floating seat, when the ejector rod displaces towards the side of the workpiece, the piston on the ejector rod extrudes the medium in the upper chamber and pushes it into the connected outer chamber, which plays a role of slowing down the axial displacement of the ejector rod in this process, which can reduce the extrusion and wear caused by the fast response of the cylinder driving the ejector rod to quickly push the workpiece. When the workpiece processing is subjected to axial force combined with thermal expansion of the material itself, the ejector rod is subjected to reverse displacement due to axial force, the piston compresses the medium in the lower chamber and enters the outer chamber through the compression valve, which plays a role of floating adjustment and slows down the ejector rod, thereby maintaining the positioning stability of the workpiece.

[0042] Preferably, the guide valve comprises:

[0043] a first guide seat; and

[0044] a second guide seat connected with the first guide seat, the second guide seat is provided with a first damping channel;

[0045] The ejector rod is arranged in the first guide seat and the second guide seat, the first damping channel is connected with the outer chamber and the first overflow channel, and one end of the first overflow channel is connected with the upper chamber.

[0046] By using the above technical scheme, the connection of the first guide seat and the second guide seat can improve the guidance of the axial displacement of the ejector rod. At the same time, when the piston displaces towards the side of the guide valve, the medium in the upper chamber enters the first damping channel through the first overflow channel, at this time, the medium flow rate decreases and plays a role of slowing down the movement of the ejector rod, thereby protecting the positioning of the workpiece.

[0047] Preferably, the compression valve comprises:

[0048] a valve seat, the valve seat is connected with the ejector rod and has a second overflow channel;

[0049] a valve cover, one end of the valve cover is connected with the valve seat, the valve cover and the valve seat have a first overflow chamber, the valve cover is connected with the ejector rod and has a third overflow channel connected with the lower chamber and the first overflow chamber;

[0050] a valve plate accommodated in the first overflow chamber and separating the first overflow chamber into a first chamber and a second chamber, the valve plate being provided with a second damping channel communicating the first chamber and the second chamber;

[0051] a resilient member installed in the first chamber and abutting against the valve plate to force the valve plate to always have a tendency to move towards the valve seat; and

[0052] a cover connected to one end of the floating seat;

[0053] wherein one end of the valve seat abuts against the cover and a second overflow chamber is formed between the valve seat and the cover, the second overflow chamber communicating the second overflow channel; a third damping channel communicating the second overflow chamber and the outer chamber is further formed between the valve seat and the cover.

[0054] By adopting the above technical scheme, when the workpiece acts on the center component, the piston pushes the stopper from the lower chamber into the first overflow chamber through the third overflow channel, and then flows into the second overflow chamber through the second overflow channel, and finally flows into the outer chamber through the third damping channel. In this process, the double-damping-channel arrangement of the second damping channel and the third damping channel makes the moving speed of the top rod slower, thereby ensuring the stable abutment between the workpiece and the center component and achieving floating adjustment, and reducing the possibility of workpiece extrusion wear.

[0055] Preferably, when the center component abuts against the workpiece, the cylinder shaft of the air cylinder is in a free telescopic state.

[0056] By adopting the above technical scheme, the floating tail part of the workpiece is positioned and abuts against the workpiece before machining, and after the positioning and abutting is completed, the air cylinder is unloaded to release the pressure so that the cylinder shaft is in a free telescopic state, thereby reducing the force of the air cylinder on the top rod and reducing the elastic stiffness of the center component, and the floating adjustment can be applied to the working condition with a larger material thermal expansion coefficient and a larger machining axial force.

[0057] Preferably, the rotary milling mechanism comprises:

[0058] a support seat comprising a first seat body and a second seat body, the first seat body having a first mounting hole;

[0059] an inner rotary milling head having a first rotating shaft extending outward, the first rotating shaft being rotatably connected in the first mounting hole; and

[0060] an adjusting assembly for driving the first rotating shaft to rotate in the first mounting hole, the adjusting assembly comprising a worm member rotatably connected to the support seat and a worm wheel engaged with the worm member, the worm wheel being connected with the first rotating shaft.

[0061] By adopting the technical scheme, the rotating worm member can drive the worm gear to rotate, the worm gear drives the first rotating shaft to rotate, and then drives the whole internal rotary milling head to rotate to realize adjustment of a cutting swing angle.

[0062] Preferably, the angle detection assembly comprises:

[0063] a transmission shaft;

[0064] an angle sensor; and

[0065] a coupling connecting the transmission shaft and the angle sensor.

[0066] The internal rotary milling head further comprises a second rotating shaft, the second rotating shaft is rotationally connected in the second mounting hole, and one end of the transmission shaft is connected with the second rotating shaft.

[0067] By adopting the technical scheme, the second rotating shaft supports and rotates the whole internal rotary milling head in combination with the first rotating shaft, thereby improving the stability of rotation during swing angle adjustment. Meanwhile, when the internal rotary milling head rotates, the rotation of the second rotating shaft drives the transmission shaft to rotate, the transmission shaft inputs the rotation angle to the angle sensor through the coupling, and then the swing angle adjustment of the internal rotary milling head can be visualized, thereby improving the controllability during adjustment.

[0068] To sum up, the present application has at least one of the following beneficial technical effects:

[0069] 1. The floating tailstock structure in combination with the connecting structure between the shaft core and the front bearing assembly of the electric spindle improves the axial bearing and floating adjustment capability, and increases the service life of the equipment.

[0070] 2. The bidirectional damping structure used in the floating tailstock can achieve slow-moving effect when positioning and resisting the initial position of the workpiece and when axially loading during workpiece machining, thereby better reducing the extrusion wear between the workpiece and the floating tailstock and improving the service life of the component.

[0071] 3. The detachable connecting structure of the rotor and the shaft core facilitates quick disassembly and assembly of the component, and when the shaft core is subjected to axial force, the connecting strength of the rotor can be better ensured by using the conical surface resisting structure, so that the electric spindle operates more stably.

[0072] 4. The swing angle adjustment of the internal rotary milling head is realized by setting the adjusting assembly on the rotary milling mechanism, and the visualization of angle adjustment is realized in combination with the setting of the angle sensor. BRIEF DESCRIPTION OF DRAWINGS

[0073] Figure 1 FIG. 1 is a structure schematic view of the internal rotary milling machining device in one perspective view.

[0074] Figure 2This is a schematic diagram of the internal rotary milling device from another perspective;

[0075] Figure 3 This is a sectional view of the electric spindle;

[0076] Figure 4 This diagram mainly illustrates the connection between the rotor and the spindle core inside the electric spindle;

[0077] Figure 5 for Figure 4 Enlarged view of part A;

[0078] Figure 6 This is a schematic diagram of the rotary milling mechanism;

[0079] Figure 7 This is a sectional view of the rotary milling mechanism;

[0080] Figure 8 This is a schematic diagram of the adjusting component in the rotary milling mechanism;

[0081] Figure 9 This is a schematic diagram of the floating tailstock structure;

[0082] Figure 10 This diagram mainly illustrates the connection of the top-mounted components;

[0083] Figure 11 This is a schematic diagram showing the structure of the pilot valve and the rotary center.

[0084] Figure 12 This diagram mainly shows the structure of the compression valve.

[0085] 10, frame; 20, motorized spindle; 201, locking ring; 2011, second conical surface; 202, fastener; 21, spindle seat; 22, stator; 23, rotor; 24, shaft core; 241, blocking portion; 242, shaft shoulder; 25, jacket; 251, main body portion; 252, extension portion; 2521, first conical surface; 26, pull rod; 261, pull claw; 262, hydraulic cylinder; 27, guide sleeve; 28, front bearing assembly; 281, front bearing; 282, front bearing seat; 283, first front blocking ring; 284, front end cover; 285, first rear blocking ring; 286, first locking nut; 29, rear bearing assembly; 291, rear bearing; 292, rear bearing seat; 293, second front blocking ring; 294, second rear blocking ring; 295, second locking nut; 30, rotary milling mechanism; 31, first servo motor; 32, second servo motor; 33, first rotary milling sliding seat; 34, guide rail seat; 35, second rotary milling sliding seat; 36, inner rotary milling head; 361, tool holder; 362, third servo motor; 363, driving pulley; 364, driven pulley; 365, first rotating shaft; 366, second rotating shaft; 367, transmission shaft; 368, shaft coupling; 369, angle sensor; 37, first seat body; 371, adjusting groove; 38, second seat body; 381, dustproof cylinder; 39, adjusting assembly; 391, threaded portion; 392, optical axis segment; 393, wrench segment; 394, first rolling bearing; 395, worm wheel; 40, floating tailstock; 401, fourth servo motor; 41, floating sliding seat; 42, floating seat; 421, outer chamber; 422, upper chamber; 4221, first overflow channel; 423, lower chamber; 424, oil inlet hole; 425, oil outlet hole; 43, air cylinder; 44, tail plate; 441, guide rod; 45, ejector rod; 451, piston; 452, first limit ring; 46, rotary center; 461, plane bearing; 462, blocking ring; 463, second rolling bearing; 464, gland; 465, center; 47, second limit ring; 48, guide valve; 481, first guide seat; 482, second guide seat; 4821, first damping channel; 483, shaft seal; 484, first sealing ring; 49, compression valve; 491, valve seat; 4911, second overflow channel; 4912, third damping channel; 492, valve cover; 4921, third overflow channel; 493, valve plate; 4931, second damping channel; 494, cover; 495, elastic member; 496, first chamber; 497, second chamber; 498, second overflow chamber; 499, second sealing ring. DETAILED DESCRIPTION

[0086] The application will be further described below in conjunction with the drawings.

[0087] It should be understood that when an element as a layer, region or plate is referred to as being "on" another element, it can be directly on the other element or intervening elements can also be present. In addition, it should be understood that when an element is referred to as being "connected" to another element, it can be directly connected to the other element or intervening elements can also be present. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0088] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as commonly understood by one of ordinary skill in the art to which this application belongs. The terminology used in the description of the application herein is for the purpose of describing particular embodiments only and is not intended to be limiting of the application. As used herein, the term "and / or" includes any and all combinations of one or more of the associated listed items.

[0089] Figure 1 With Figure 2 The structure of an internal rotary milling processing device is shown, which comprises a rack 10, an electric spindle 20, a rotary milling mechanism 30 and a floating tailstock 40 mounted on the rack 10, the rotary milling mechanism 30 is arranged between the electric spindle 20 and the floating tailstock 40, the electric spindle 20 is used for clamping and driving the workpiece to rotate, the rotary milling mechanism 30 is used for milling the workpiece, and the floating tailstock 40 is used for positioning the end abutting against the workpiece. The processing device can be suitable for thread processing of long workpieces.

[0090] In combination Figures 3 to 5 The electric spindle 20 comprises a spindle seat 21 fixed on the rack 10, the spindle seat 21 has an installation cavity with two open sides, a stator 22 is fixed in the installation cavity, an axis core 24 is arranged in the stator 22, and a rotor 23 is arranged on the axis core 24 and placed in the inner hole of the stator 22 to realize mutual coupling of the two.

[0091] The two ends of the axis core 24 respectively extend out of the installation cavity of the spindle seat 21, and an annular clamping sleeve 25 is arranged on the axis core 24, and the two are connected in the form of transition fit, so that the rotation of the axis core 24 can drive the rotation of the clamping sleeve 25.

[0092] The clamping sleeve 25 comprises a cylindrical main body part 251 and extension parts 252 connected to the two ends of the main body part 251, a through installation hole is formed in the middle of the rotor 23, and the clamping sleeve 25 is arranged in the installation hole, so that the main body part 251 is arranged in the installation hole and the extension parts 252 on both sides extend out of the installation hole. In this embodiment, the rotor 23 and the clamping sleeve 25 can adopt clearance fit or transition fit, and when transition fit is adopted, only axial force needs to be applied to the rotor 23 to hit the outside of the clamping sleeve 25.

[0093] The two extensions 252 of the sleeve 25 are symmetrically distributed, one of the extensions 252 abuts against one side of the shaft core 24 to achieve installation positioning, and the outer circumferential surface of the sleeve 25 is provided with a first tapered surface 2521. The sleeve 25 is connected with a locking ring 201, the locking ring 201 has an inner hole, the inner circumferential surface of the inner hole is provided with a second tapered surface 2011, and then the locking ring 201 can be fixedly connected with the extension 252 when the extension 252 enters the inner hole of the locking ring 201 and when the first tapered surface 2521 and the second tapered surface 2011 abut against each other. At the same time, when the locking ring 201 slides along the first tapered surface 2521 towards one side of the main body part 251, the extrusion force of the first tapered surface 2521 and the second tapered surface 2011 gradually increases to improve the connection strength between the locking ring 201 and the extension 252.

[0094] The locking ring 201 is provided with a plurality of through holes in the side circumferential surface, a fastener 202 is arranged in the through hole, one end of the fastener 202 is connected with the rotor 23, and then the connection between the locking ring 201 and the rotor 23 is achieved. Further, in the embodiment, the fastener 202 is a locking screw, the locking screw is threadedly connected with the rotor 23, when the locking ring 201 axially slides relative to the extension 252 and slides to the maximum stroke position close to one side of the main body part 251, the fastener 202 is connected with the rotor 23 by penetrating through the through hole, and the fixing of the rotor 23, the sleeve 25 and the shaft core 24 is achieved.

[0095] The electric spindle 20 is further provided with a front bearing assembly 28 and a rear bearing assembly 29, the front bearing assembly 28 and the rear bearing assembly 29 are respectively arranged on both sides of the rotor 23, and the front bearing assembly 28 is close to one end of the workpiece clamping. The front bearing assembly 28 comprises a front bearing seat 282 arranged on the shaft core 24, a plurality of adjacent front bearings 281, a front end cover 284, a first front retainer ring 283, a first rear retainer ring 285 and a first locking nut 286.

[0096] The front bearing seat 282 is connected with the main shaft seat 21, the plurality of front bearings 281 are arranged in the front bearing seat 282, the first front retainer ring 283 and the second rear retainer ring 294 are both arranged on the shaft core 24, one end surface of the first front retainer ring 283 abuts against one side of the inner ring of the plurality of front bearings 281, the front end cover 284 is connected with the front bearing seat 282, the front end cover 284 has an inner ring extending towards one side of the shaft core 24, the inner ring is connected with the front retainer ring and abuts against one side of the outer ring of the plurality of front bearings 281 to limit the front bearings 281 in one axial direction; one end surface of the first rear retainer ring 285 abuts against the other side of the plurality of front bearings 281 to limit the front bearings 281 in the other axial direction, and the first locking nut 286 is threadedly connected with the shaft core 24 and abuts against the first rear retainer ring 285 to limit the axial movement of the first rear retainer ring 285.

[0097] The shaft core 24 is integrally provided with a blocking portion 241 extending away from the radial direction at the end close to the clamping of the workpiece, and the blocking portion 241 abuts against one side of the first front blocking ring 283 and / or the inner ring to limit the axial movement of the first front blocking ring 283 and / or the front end cover 284.

[0098] The electrospindle 20 further comprises a pull rod 26 arranged in the shaft core 24, a pull claw 261 connected to one end of the pull rod 26, and a guide sleeve 27 arranged on the pull claw 261. The pull rod 26 cooperates with the shaft core 24 to rotate synchronously, and the pull rod 26 can also axially slide relative to the shaft core 24. The pull claw 261 has a clamping hole for clamping the workpiece. The pull claw 261 has a plurality of circumferentially arranged pull claw pieces, and adjacent two pull claw pieces have a deformation groove. The guide sleeve 27 is arranged outside the pull claw 261, and the guide sleeve 27 is connected with the blocking portion 241 of the shaft core 24.

[0099] The other end of the pull rod 26 is connected with a hydraulic cylinder 262, which can drive the pull rod 26 to axially displace relative to the shaft core 24. When the pull rod 26 moves axially towards the shaft core 24, the plurality of pull claw pieces extrude the inner wall of the guide sleeve 27 to shrink and reduce the hole diameter of the clamping hole, thereby clamping and releasing the workpiece. Conversely, the pull claw pieces reset under their own elasticity to increase the hole diameter of the clamping hole to release the workpiece.

[0100] The rear bearing assembly 29 comprises a rear bearing seat 292, a plurality of adjacent rear bearings 291, a second front blocking ring 293, a second rear blocking ring 294, and a second locking nut 295. The plurality of rear bearings 291 are arranged on the shaft core 24 and arranged in the rear bearing seat 292. The second front blocking ring 293 and the second rear blocking ring 294 are also arranged on the shaft core 24. The second front blocking ring 293 abuts against one side of the plurality of rear bearings 291, and the second rear blocking ring 294 abuts against the other side of the plurality of rear bearings 291 to limit the axial movement of the rear bearings 291. The second front blocking ring 293 also abuts against one end of the clamping sleeve 25 to limit the axial movement of the clamping sleeve 25. The second locking nut 295 is threadedly connected with the shaft core 24 and abuts against one side of the second rear blocking ring 294 to limit the axial movement of the second rear blocking ring 294.

[0101] In combination Figures 6 to 8 The milling mechanism 30 comprises a first milling sliding seat 33, a guide rail seat 34, a second milling sliding seat 35, and an inner milling head 36. The guide rail seat 34 is fixedly connected with the first milling sliding seat 33. The second milling sliding seat 35 is arranged on the guide rail seat 34 and can slide relative to the guide rail seat 34. Specifically, the first servo motor 31 is arranged on one side of the guide rail seat 34. The first servo motor 31 is connected with the second milling sliding seat 35 through a screw nut pair. The first servo motor 31 can drive the second milling sliding seat 35 to slide. The inner milling head 36 is arranged on the second milling sliding seat 35, thereby adjusting the machining position of the workpiece.

[0102] The first rotary milling sliding seat 33 is connected with the rack 10 and can slide relative to the rack 10. Specifically, a second servo motor 32 is arranged on one side of the rack 10. The second servo motor 32 is connected with the first rotary milling sliding seat 33 through a screw-nut pair, so as to realize the sliding connection between the first rotary milling sliding seat 33 and the rack 10. The sliding directions of the first rotary milling sliding seat 33 and the second rotary milling sliding seat 35 are opposite to each other.

[0103] The second rotary milling sliding seat 35 is further provided with a support seat. The support seat comprises a first seat body 37 and a second seat body 38 arranged at intervals. The inner rotary milling head 36 is rotationally connected to the first seat body 37 and the second seat body 38. The inner rotary milling head 36 comprises a third servo motor 362, a driving pulley 363 connected with the third servo motor 362, a driven pulley 364, and a tool holder 361. The driving pulley 363 is connected with the driven pulley 364 through a belt. A cutter head is connected to one end of the driven pulley 364, so as to synchronously drive the cutter head to rotate when the driven pulley 364 rotates. The cutter head is rotationally connected to the tool holder 361. The rotating structure of the cutter head is a prior art, which is briefly described and not regarded as the main point of the present application.

[0104] The inner rotary milling head 36 further comprises a first rotating shaft 365 and a second rotating shaft 366. The second rotating shaft 366 is coaxially arranged with the second rotating shaft 366, and the axis is L. The first rotating shaft 365 is rotationally connected to the first seat body 37. The second rotating shaft 366 is rotationally connected to the second seat body 38. Specifically, a first mounting hole is formed in the first seat body 37. A second mounting hole is formed in the second seat body 38. The first rotating shaft 365 is rotationally connected to the first mounting hole. The second rotating shaft 366 is rotationally connected to the second mounting hole.

[0105] The inner rotary milling head 36 further comprises an adjusting assembly 39 for driving the first rotating shaft 365 to rotate. The adjusting assembly 39 is mounted on the first seat body 37 and comprises a worm member rotationally connected to the first seat body 37 and a worm wheel 395 engaged with the worm member. An adjusting groove 371 is formed in the first seat body 37 and communicates with the first mounting hole. One end of the worm member extends into the adjusting groove 371 and is rotationally connected with the first seat body 37. The other end of the worm member extends out of the adjusting groove 371.

[0106] The worm member comprises an integral threaded portion 391, a light shaft segment 392, and a wrench segment 393. The threaded portion 391 is provided with threads and is engaged with the worm wheel 395. The light shaft segment 392 is provided with a first rolling bearing 394. The first rolling bearing 394 is limited in the mounting groove which communicates with the adjusting groove 371. The wrench segment 393 is provided with an outer contour which can be matched with a hand tool or an electric tool, such as a regular hexagon to match a hexagonal wrench.

[0107] The first rotating shaft 365 is a stepped shaft, one end of the first rotating shaft 365 is rotatably connected in the first mounting hole, the worm wheel 395 is mounted on the first rotating shaft 365 and accommodated in the first mounting hole, the worm wheel 395 is connected with the first rotating shaft 365 through a plurality of circumferentially distributed fasteners 202, further improving the connection firmness of the first rotating shaft 365, and the rotation of the worm wheel 395 can synchronously drive the rotation of the first rotating shaft 365.

[0108] The inner rotating milling head 36 further comprises an angle detection assembly, the angle detection assembly comprising a transmission shaft 367, a shaft coupling 368 and an angle sensor 369, the transmission shaft 367 is connected to the end face of the second rotating shaft 366, the end of the transmission shaft 367 away from the second rotating shaft 366 is connected with the angle sensor 369 through the shaft coupling 368, in the embodiment, the angle sensor 369 is a rotating shaft type angle sensor 369, the rotating shaft of the angle sensor 369 is connected with the transmission shaft 367 through the shaft coupling 368.

[0109] One end of the second seat body 38 is further connected with a dustproof cylinder 381, the angle sensor 369 is mounted at one end of the dustproof cylinder 381 and the rotating shaft extends into the dustproof cylinder 381, the dustproof cylinder 381 simultaneously accommodates the shaft coupling 368 and the transmission shaft 367. In order to realize the visualization of the degree of the angle sensor 369, the angle sensor 369 can be connected with a numerical control system and the angle degree is displayed on an operation panel, the specific transmission connection mode is not described as prior art.

[0110] When the inner rotating milling tool device is manually adjusted, the worm gear is driven to rotate by a manual or electric tool, the rotation of the worm gear drives the rotation of the worm wheel 395, the rotation of the worm wheel 395 drives the rotation of the first rotating shaft 365, the rotation of the first rotating shaft 365 drives the rotation of the entire inner rotating milling head 36, and then the angle adjustment is realized.

[0111] In combination Figure 9 With Figure 10 The floating tailstock 40 comprises a floating slide 41, a floating seat 42 and a center point assembly arranged in the floating seat 42. The floating slide 41 is arranged on the rack 10, and a fourth servo motor 401 is further arranged on one side of the rack 10, the fourth servo motor 401 is connected with the floating slide 41 through a screw nut pair, and then the floating slide 41 can be driven to slide away from or close to the side of the electric spindle 20 on the rack 10.

[0112] The top tip assembly comprises a cylinder 43 arranged on the floating base 42, and a tail plate 44 connected to the cylinder 43. The top tip assembly further comprises a top rod 45 and a rotary top tip 46 connected to the top rod 45, one end of the top rod 45 is connected to the tail plate 44, and the cylinder 43 can drive the top rod 45 to slide on the floating base 42 through the tail plate 44. In order to improve the sliding guiding property of the top rod 45, a guide rod 441 is further connected to the tail plate 44 and slides on the floating base 42 together with the top rod 45.

[0113] In combination Figure 11 Both ends of the top rod 45 extend out of the floating base 42, and the top rod 45 is arranged at a position with a first limiting ring 452 at the end. A second limiting ring 47 is arranged at the end of the top rod 45 close to the tail plate 44, and the first limiting ring 452 and the second limiting ring 47 limit the maximum axial displacement of the top rod 45 relative to the floating base 42.

[0114] The rotary top tip 46 is arranged at the end of the top rod 45 close to the first limiting ring 452, and comprises a top tip 465, a plane bearing 461, a blocking ring 462, a second rolling bearing 463, and a gland 464. The plane bearing 461, the blocking ring 462, the second rolling bearing 463, and the gland 464 are sequentially arranged on the top tip 465 and accommodated in the end of the top rod 45, and the gland 464 is threadedly connected to the end of the top rod 45 to axially limit the top tip 465 and the plane bearing 461, the blocking ring 462, and the second rolling bearing 463.

[0115] The floating base 42 has an outer chamber 421 and an inner chamber, and the outer chamber 421 and the inner chamber are filled with hydraulic oil. The top rod 45 is arranged in the inner chamber and further has a piston 451, which is slidably connected to the inner chamber and divides the inner chamber into an upper chamber 422 and a lower chamber 423.

[0116] The floating base 42 further has a guide valve 48 for connecting the outer chamber 421 and the upper chamber 422, and a compression valve 49 for connecting the outer chamber 421 and the lower chamber 423. Both ends of the top rod 45 extend out of the floating base 42 through the guide valve 48 and the compression valve 49.

[0117] The guide valve 48 comprises a first guide base 481 and a second guide base 482 connected to each other. In this embodiment, the first guide base 481 and the second guide base 482 are connected in a clamping manner, and the top rod 45 is slidably connected to the first guide base 481 and the second guide base 482. A shaft seal 483 is arranged between the second guide base 482 and the outer wall of the top rod 45, and a first sealing ring 484 is arranged between the second guide base 482 and the inner wall of the outer chamber 421 to improve the sealing property of the guide valve 48 with the outside.

[0118] The outer circumferential wall of the top rod 45 and the inner hole of the second guide seat 482 have a gap to form a first overflow passage 4221, the first guide seat 482 is provided with a first damping passage 4821 in the circumferential direction, the first overflow passage 4221 is respectively connected with the upper cavity 422 and the first damping passage 4821, the first damping passage 4821 is connected with the outer chamber 421, thereby realizing the communication between the outer chamber 421 and the upper cavity 422.

[0119] In combination Figure 12 The compression valve 49 comprises a valve seat 491, a valve cover 492, a valve plate 493 and a cover 494. The valve cover 492 is connected with the valve seat 491, and a first overflow chamber is formed between the valve cover 492 and the valve seat 491. The valve plate 493 is arranged in the first overflow chamber and divides the first overflow chamber into a first chamber 496 and a second chamber 497. The elastic member 495 is arranged in the first chamber 496, and the two ends of the elastic member 495 abut against the valve cover 492 and the valve plate 493 respectively. The elastic member 495 can force the valve plate 493 to always have a tendency to move towards the valve seat 491.

[0120] The valve seat 491 abuts against the cover 494, and the cover 494 is sealingly connected with one end of the floating seat 42. The second sealing ring 499 is arranged between the cover 494 and the top rod 45. The valve seat 491 and the outer circumferential wall of the top rod 45 have a gap to form a second overflow passage 4911. The valve cover 492 and the outer circumferential wall of the top rod 45 also have a gap to form a third overflow passage 4921. The valve plate 493 is provided with a plurality of second damping passages 4931. The valve seat 491 is provided with a third damping passage 4912 on the outer circumferential wall. The third overflow passage 4921 is connected with the lower cavity 423 and the first chamber 496. The second damping passage 4931 is connected with the first chamber 496 and the second chamber 497. The second overflow passage 4911 is connected with the second chamber 497 and the second overflow chamber 498. The third damping passage 4912 is connected with the second overflow chamber 498 and the outer chamber 421, thereby realizing the communication between the lower cavity 423 and the outer chamber 421.

[0121] The inner rotary milling device is used for thread processing of the workpiece. One end of the workpiece is clamped and rotated by the electric spindle 20. The workpiece passes through the inner hole of the cutter seat 361 of the inner rotary milling head 36 and abuts against the tailstock center 465 of the floating tailstock 40. When the tailstock center 465 moves towards the workpiece, the fourth servo motor 401 drives the floating slide 41 to move to the side of the end of the workpiece first, and then the cylinder 43 drives the top rod 45 to displace relative to the floating seat 42. The top rod 45 drives the piston 451 to move in the inner chamber and sequentially passes the hydraulic oil from the upper cavity 422 to the first overflow channel 4221 and the first damping channel 4821 into the outer cavity 421. The hydraulic oil in the outer cavity 421 enters the lower cavity 423 through the compression valve 49 to realize the slow movement of the top rod 45 towards the side of the workpiece. In the embodiment, after the tailstock center 465 completes the positioning abutment with the workpiece, the cylinder 43 is unloaded to make the cylinder 43 shaft in a free and retractable state to reduce the pressure retaining force on the top rod 45, which is suitable for positioning of the workpiece with a large thermal expansion coefficient. Of course, when the workpiece with a small thermal expansion coefficient is processed, the axial deformation amount of the workpiece will not be too large, and the cylinder 43 can always maintain the pressure retaining state, and the top rod 45 does not need to have a large floating displacement amount.

[0122] When the axial force generated by the workpiece processing acts on the top rod 45, the top rod 45 can be reversely displaced. The piston 451 pushes the hydraulic oil in the lower cavity 423 to sequentially pass through the third overflow channel 4921, the first cavity 496, the second damping channel 4931, the second cavity 497, the second overflow channel 4911, the second overflow cavity 498 and the third damping channel 4912 into the outer cavity 421. The hydraulic oil in the outer cavity 421 flows back to the upper cavity 422 through the guide valve 48. Due to the multiple damping channels of the compression valve 49, the top rod 45 has a certain axial supporting force on the workpiece and has a floating adjustment capability.

[0123] The above are preferred embodiments of the present application, which do not limit the protection scope of the present application. Therefore, equivalent changes made on the basis of the structure, shape and principle of the present application should be covered by the protection scope of the present application.

Claims

1. An internal rotary milling apparatus, characterized in that, include: Rack (10); An electric spindle (20) is used to drive the rotation of the workpiece. The electric spindle (20) is mounted on the frame (10) and includes a spindle core (24) and a front bearing assembly (28) mounted on one end of the spindle core (24). A rotary milling mechanism (30) is mounted on a frame (10); and A floating tailstock (40) abuts against one end of the workpiece. The floating tailstock (40) includes a floating seat (42) and a center assembly. The center assembly includes: The top rod (45) is slidably connected to the floating seat (42); Piston (451) is connected to push rod (45); The rotating tip (46) is rotatably connected to one end of the push rod (45); and The cylinder (43) is connected to the other end of the push rod (45) and is used to drive the push rod (45) to move relative to the floating seat (42); The floating seat (42) has an outer chamber (421) and an inner chamber, both of which contain hydraulic oil. The piston (451) is slidably connected to the inner chamber and divides the inner chamber into an upper chamber (422) and a lower chamber (423). The floating seat (42) is also provided with a guide valve (48) for connecting the outer chamber (421) and the upper chamber (422) and a compression valve (49) for connecting the outer chamber (421) and the lower chamber (423). The guide valve (48) includes: First guide seat (481); and The second guide seat (482) is connected to the first guide seat (481), and the second guide seat (482) has a first damping channel (4821). The push rod (45) passes through the first guide seat (481) and the second guide seat (482), and there is a first overflow channel (4221) between the push rod (45) and the second guide seat (482). The first damping channel (4821) connects the outer chamber (421) and the first overflow channel (4221), and one end of the first overflow channel (4221) connects to the upper chamber (422). The compression valve (49) includes: Valve seat (491), wherein a second overflow passage (4911) is provided between the valve seat (491) and the push rod (45). A valve cover (492) is provided, one end of which is connected to a valve seat (491). A first overflow chamber is provided between the valve cover (492) and the valve seat (491). A third overflow channel (4921) is provided between the valve cover (492) and the push rod (45) to connect the lower chamber (423) and the first overflow chamber. A valve plate (493) is housed in a first overflow chamber and divides the first overflow chamber into a first chamber (496) and a second chamber (497). A second damping channel (4931) is provided on the valve plate (493) to connect the first chamber (496) and the second chamber (497). An elastic element (495) is installed in the first chamber (496) and abuts against the valve plate (493), forcing the valve plate (493) to always tend to move towards the valve seat (491); and Cap (494); connected to one end of the floating seat (42); One end of the valve seat (491) abuts against the cover (494) and a second overflow chamber (498) is formed between the two, the second overflow chamber (498) is connected to the second overflow channel (4911); a third damping channel (4912) is also provided between the valve seat (491) and the cover (494) to connect the second overflow chamber (498) and the outer chamber (421). The rotary milling mechanism (30) is arranged between the electric spindle (20) and the floating tailstock (40), and can drive the center assembly to move relative to the floating seat (42) when the workpiece acts on the center assembly. The shaft core (24) includes an integral stop (241) extending radially from the end, the stop (241) abutting against one side of the front bearing assembly (28).

2. The internal rotary milling apparatus according to claim 1, characterized in that, The front bearing assembly (28) includes: Front bearing housing (282); Several adjacent front bearings (281) are mounted on the shaft core (24) and placed inside the front bearing housing (282); The first front retaining ring (283) is mounted on the shaft core (24) and abuts against the inner ring of the front bearing (281) on one side; A front cover (284) is connected to a front bearing housing (282), the front cover (284) having an inner ring connected to a first front retaining ring (283), the inner ring abutting against the outer ring of a front bearing (281) on one side; The first rear retaining ring (285) is mounted on the shaft core (24) and abuts against the end face of the other front bearing (281); and The first locking nut (286) is threadedly connected to the shaft core (24) and abuts against the first rear retaining ring (285). The stop (241) abuts against the first front stop ring (283) and / or the inner ring.

3. The internal rotary milling apparatus according to claim 1 or 2, characterized in that, The electric spindle (20) also includes: Rotor (23), wherein the rotor (23) has a through mounting hole; A sleeve (25) surrounds the outer peripheral wall of the shaft core (24) and passes through the mounting hole. The sleeve (25) can rotate synchronously with the shaft core (24), and both ends of the sleeve (25) extend out from the mounting hole; and Locking rings (201) are distributed at both ends of the rotor (23), and the locking rings (201) are connected to the rotor (23) by fasteners (202); The sleeve (25) includes a main body (251) and an extension (252) connected to both ends of the main body (251). The outer peripheral surface of the extension (252) is a first conical surface (2521). The locking ring (201) has an inner hole. The inner peripheral surface of the inner hole is a second conical surface (2011). The extension (252) enters the inner hole and the first conical surface (2521) and the second conical surface (2011) abut against each other.

4. The internal rotary milling apparatus according to claim 3, characterized in that, The electric spindle (20) also includes a rear bearing assembly (29), which comprises: Rear bearing housing (292); Several adjacent rear bearings (291) are mounted on the shaft core (24) and placed inside the rear bearing housing (292); The second front retaining ring (293) is mounted on the shaft core (24) and abuts against the end face of the rear bearing (291) on one side; The second rear retaining ring (294) is mounted on the shaft core (24) and abuts against the end face of the other rear bearing (291); and The second locking nut (295) is threaded to the shaft core (24) and abuts against the second rear retaining ring (294).

5. The internal rotary milling apparatus according to claim 1, characterized in that, When the top component comes into contact with the workpiece, the cylinder shaft of the cylinder (43) is in a free extension and retraction state.

6. The internal rotary milling apparatus according to claim 1, characterized in that, The rotary milling mechanism (30) includes: The support base includes a first base body (37) and a second base body (38), wherein the first base body (37) has a first mounting hole; An internal milling head (36) having an outwardly extending first rotating shaft (365) rotatably connected within a first mounting hole; and An adjustment assembly (39) is used to drive a first rotating shaft (365) to rotate within a first mounting hole. The adjustment assembly (39) includes a worm gear rotatably connected to a support base and a worm wheel (395) meshing with the worm gear. The worm wheel (395) is connected to the first rotating shaft (365).

7. The internal rotary milling apparatus according to claim 6, characterized in that, It also includes an angle detection component, which includes: Drive shaft (367); Angle sensor (369); and Coupling (368) connects drive shaft (367) and angle sensor (369). The internal milling head (36) further includes a second rotating shaft (366), which is rotatably connected to the second mounting hole, and one end of the transmission shaft (367) is connected to the second rotating shaft (366).

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