High speed air bearing spindle

Abstract

The present application discloses a high-speed air-floating main shaft, including a front air-floating bearing, a rear air-floating bearing, a shell and an inner shaft. The shell is sleeved outside the front and rear air-floating bearings, and the shell is provided with a rear-end driving airway, a front-end driving airway and an air-floating bearing air supply duct. The inner shaft includes a rear-end turbine part, a rod body part and a front-end turbine part arranged in sequence, the rod body part is movably mounted on the inner side of the air-floating bearing, the rear-end turbine part corresponds to the rear-end driving airway, the front-end turbine part corresponds to the front-end driving airway, and the air-floating bearing air supply duct is used to supply air to the air-floating bearing. When the rear-end driving airway of the present application is ventilated, the airflow drives the rear-end turbine part so that the inner shaft rotates along the first rotation direction. When the front-end driving airway is ventilated, the airflow drives the front-end turbine part so that the inner shaft rotates along the second rotation direction. The first rotation direction is opposite to the second rotation direction, so that the inner shaft can rotate in both directions.

Description

Technical Field

[0001] The present application relates to the field of machine tool processing technology, and in particular to a high-speed air-floating spindle. Background Art

[0002] In machining, the tool is mounted on the spindle, and the spindle drives the tool to rotate to process the workpiece. Existing spindles can be driven by motors or pneumatically. Existing motor-driven spindles usually have problems such as complex structure, easy heating and aging of the motor, and pneumatic-driven spindles can only rotate in the same direction, which has problems such as low applicability. Summary of the invention

[0003] In view of this, it is necessary to provide a high-speed air-floating spindle capable of bidirectional rotation.

[0004] Some embodiments of the present application provide a high-speed air-floating spindle, which includes a front air-floating bearing, a rear air-floating bearing, a housing, and an inner shaft.

[0005] The front and rear air bearings are arranged at intervals along the axial direction of the inner shaft, and along the circumference of the front and rear air bearings, the outer peripheral walls of the front and rear air bearings are both provided with bearing annular grooves, and the bearing annular grooves are penetrated by a plurality of radial air holes;

[0006] The shell comprises an outer shell, a front end cover, a rear end cover, a front drive cover and a rear drive cover, the outer shell is sleeved outside the front and rear air bearings, the front end cover and the rear end cover are respectively arranged at the two ends of the inner shaft, the rear end cover is penetrated to form a rear end drive air passage, the rear end cover is also penetrated with a front air drive air inlet and a rear air drive air inlet connected with the rear end drive air passage, the outer shell is penetrated with a connecting pipe along the axial direction of the inner shaft, the front air drive air inlet is connected with the connecting pipe to form the front end drive air passage;

[0007] The inner shaft comprises a rear turbine part, a rod body part and a front turbine part which are arranged in sequence, the two ends of the rod body part are inserted into the front and rear air bearings, and the outer diameters of the rear turbine part and the front turbine part are both larger than the outer diameter of the rod body part;

[0008] The rear drive cover is arranged between the rear end cover and the housing, a rear end annular groove is recessed on one side of the rear drive cover facing the rear end cover, the rear end annular groove is communicated with the rear end drive airway, the rear drive cover is also penetrated by a plurality of rear end inclined holes, the plurality of rear end inclined holes are distributed in an annular shape on the rear drive cover, the rear end inclined holes are used to guide the gas in the rear end annular groove to the rear end turbine part;

[0009] The front driving cover is arranged between the front end cover and the housing, the front driving cover is provided with a front end annular groove on one side facing the front end cover, the front driving cover is also provided with an air hole and a plurality of front end inclined holes, the air hole connects the front end driving airway with the front end annular groove, the plurality of front end inclined holes are evenly distributed in the front driving cover in an annular shape, and the front end inclined hole is used to guide the gas in the front end annular groove to the front end turbine part;

[0010] The rear end cover is also provided with an air-floating air inlet, and the rear end cover, the rear drive cover and the housing are sequentially penetrated corresponding to the air-floating air inlet to form an air-floating bearing air supply passage, and the air-floating bearing air supply passage is connected with the bearing annular grooves of the front and rear air-floating bearings;

[0011] The rear air-floating bearing is provided with a rear axial air hole, the air inlet end of the rear axial air hole is connected with the bearing annular groove, and the air outlet end of the rear axial air hole faces the rear end turbine part; the front air-floating bearing is provided with a front axial air hole, the air inlet end of the front axial air hole is connected with the bearing annular groove, and the air outlet end of the front axial air hole faces the front end turbine part;

[0012] When the rear end drives airway ventilation, the airflow drives the rear end turbine part to rotate the inner shaft along a first rotation direction. When the front end drives airway ventilation, the airflow drives the front end turbine part to rotate the inner shaft along a second rotation direction. The first rotation direction is opposite to the second rotation direction.

[0013] The above-mentioned rear end turbine part is driven by the gas introduced into the rear end driving air duct, and the front end turbine part is driven by the gas introduced into the front end driving air duct. The rotation direction of the rear end turbine part is opposite to that of the front end turbine part, so that the inner shaft can rotate in both directions. The bidirectionally rotating inner shaft can be connected to processing tools with different rotation directions, thereby improving the applicability of the high-speed air-floating spindle.

[0014] In at least one embodiment, the outer peripheral wall of the rear air bearing is provided with a rear inflation groove, which is connected to the rear axial air hole, and the front air bearing is provided with a front inflation groove, which is connected to the front axial air hole.

[0015] The above-mentioned rear inflation groove and front inflation groove can respectively increase the volume of the air supply chamber at the rear axial air hole and the front axial air hole, which is used to homogenize the pressure distribution in the air chamber so that each air inlet hole can obtain a stable and balanced airflow supply.

[0016] In at least one embodiment, the front air bearing is provided with a plurality of bearing annular grooves, the plurality of bearing annular grooves are arranged at intervals along the axial direction of the front air bearing, an axial groove is also provided on the outer peripheral wall of the front air bearing, and the plurality of bearing annular grooves are connected through the axial grooves; and / or, the rear air bearing is provided with a plurality of bearing annular grooves, the plurality of bearing annular grooves are arranged at intervals along the axial direction of the rear air bearing, an axial groove is also provided on the outer peripheral wall of the rear air bearing, and the plurality of bearing annular grooves are connected through the axial grooves.

[0017] In at least one embodiment, the rotation axis of the front end turbine part, the rotation axis of the rear end turbine part, the central axes of the multiple front end inclined holes, and the central axes of the multiple rear end inclined holes all coincide, and the front air drive air inlet and the air flotation air inlet on the rear end cover are symmetrically arranged according to the central axes of the multiple rear end inclined holes.

[0018] In at least one embodiment, a connecting portion for connecting a processing tool is provided on a side of the front turbine portion facing away from the rod body portion.

[0019] In at least one embodiment, a plurality of arc-shaped grooves are provided on the periphery of the rear end turbine part and the front end turbine part.

[0020] In at least one embodiment, along the axial direction of the inner shaft, the groove walls at both ends of the arc-shaped groove are penetrated, so that arc-shaped blades are formed between any two adjacent arc-shaped grooves of the rear end turbine part and between any two arc-shaped grooves of the front end turbine part.

[0021] In at least one embodiment, the radii of the rear end turbine portion and the front end turbine portion are set to 18mm-22mm, and along the bending direction of the arc blade, the arc radius R1 of the outer side of the arc blade is set to 5mm-5.5mm, and the arc radius R2 of the inner side of the arc blade is set to 7mm-7.5mm.

[0022] In at least one embodiment, the shell further includes a rear end gasket and a front end gasket, the rear end gasket is arranged between the outer shell and the rear drive cover, the front end gasket is arranged between the outer shell and the front drive cover, the rear end turbine part is located on the inner side of the rear end gasket, and the front end turbine part is located on the inner side of the front end gasket.

[0023] In at least one embodiment, the outer shell is provided with a rear end exhaust duct and a front end exhaust duct, and a plurality of exhaust ports are circumferentially provided with the rear end gasket, the air inlet end of the rear end exhaust duct is connected to the inner side of the rear end gasket, the exhaust end of the rear end exhaust duct is connected to the exhaust port, the air inlet end of the front end exhaust duct is connected to the inner side of the front end gasket, and the exhaust end of the front end exhaust duct is connected to the exhaust port. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] Figure 1 This is a schematic structural diagram of a high-speed air-bearing spindle and a processing tool provided in one embodiment of the present application.

[0025] Figure 2 A front view of a high-speed air-bearing spindle and a processing tool provided in one embodiment of the present application.

[0026] Figure 3 for Figure 2 Section view along AA.

[0027] Figure 4 A cross-sectional view of a high-speed air bearing spindle and a processing tool provided in one embodiment of the present application.

[0028] Figure 5 A cross-sectional view of a high-speed air bearing spindle and a processing tool provided in one embodiment of the present application.

[0029] Figure 6 A front view of an inner shaft provided in accordance with an embodiment of the present application.

[0030] Figure 7 A cross-sectional view of a rear end turbine portion and a rear drive cover provided in accordance with an embodiment of the present application.

[0031] Figure 8 A cross-sectional view of a high-speed air-bearing spindle and a processing tool provided in one embodiment of the present application.

[0032] Fig. 9 An exploded schematic diagram of a high-speed air-bearing spindle provided in one embodiment of the present application.

[0033] Fig.10 for Fig. 9 Schematic diagram of the structure of the middle and rear air bearings.

[0034] Fig.11 A cross-sectional view of a high-speed air bearing spindle and a processing tool provided in one embodiment of the present application.

[0035] Main component symbols

[0036] High speed air bearing spindle 100

[0037] Front air bearing 10

[0038] Rear air bearing 101

[0039] Radial air holes 11

[0040] Rear axial air hole 12

[0041] Front axial air hole 13

[0042] Bearing annular groove 14

[0043] Axial groove 15

[0044] Rear air tank 16

[0045] Front air tank 17

[0046] Housing 20

[0047] Housing 21

[0048] Connecting pipe 211

[0049] Rear exhaust duct 212

[0050] Front exhaust duct 213

[0051] Rear end cover 22

[0052] Rear drive airway 202

[0053] Rear air drive air intake 221

[0054] Front air intake 222

[0055] Front drive airway 201

[0056] Front cover 23

[0057] Rear drive cover 24

[0058] Rear end annular groove 241

[0059] Rear end inclined hole 242

[0060] Front drive cover 25

[0061] Front annular groove 251

[0062] Air hole 252

[0063] Front inclined hole 253

[0064] Air bearing air supply channel 26

[0065] Air flotation inlet 261

[0066] Rear end gasket 27

[0067] Exhaust port 271

[0068] Front washer 28

[0069] Inner shaft 30

[0070] Rear turbine section 31

[0071] Rod body 32

[0072] Front turbine section 33

[0073] Connection part 35

[0074] Arc groove 301

[0075] Curved blade 302

[0076] Accommodation space 40

[0077] Processing tools 200 DETAILED DESCRIPTION

[0078] The technical solutions in the embodiments of the present application will be described below in conjunction with the drawings in the embodiments of the present application. Obviously, the described embodiments are only part of the embodiments of the present application, rather than all of the embodiments.

[0079] It should be noted that when a component is considered to be "connected" to another component, it may be directly connected to the other component or there may be a central component at the same time. When a component is considered to be "located on" another component, it may be directly located on the other component or there may be a central component at the same time. The terms "top", "bottom", "upper", "lower", "left", "right", "front", "back", and similar expressions used herein are for illustrative purposes only.

[0080] The term "perpendicular" is used to describe the ideal state between two components. In actual production or use, there may be a state that is approximately perpendicular between the two components. For example, in combination with numerical descriptions, perpendicularity can refer to the angle between two straight lines being between 90±10°, perpendicularity can also refer to the dihedral angle between two planes being between 90°±10°, and perpendicularity can also refer to the angle between a straight line and a plane being between 90±10°. The two components described as "perpendicular" may not be absolute straight lines or planes, but may be roughly straight lines or planes. From a macroscopic perspective, a component can be considered a "straight line" or a "plane" if the overall extension direction is a straight line or a plane.

[0081] The term "parallel" is used to describe an ideal state between two components. In actual production or use, two components may be approximately parallel. For example, combined with numerical descriptions, parallel can refer to the angle between two straight lines being between 180°±10°, parallel can also refer to the dihedral angle between two planes being between 180°±10°, and parallel can also refer to the angle between a straight line and a plane being between 180°±10°. The two components described as "parallel" may not be absolute straight lines or planes, but may be roughly straight lines or planes. From a macroscopic perspective, a component can be considered a "straight line" or a "plane" if the overall extension direction is a straight line or a plane.

[0082] Unless otherwise defined, all technical and scientific terms used herein have the same meaning as those commonly understood by those skilled in the art to which this application belongs. The terms used herein in the specification of this application are only for the purpose of describing specific embodiments and are not intended to limit this application.

[0083] It should be noted that the terms "first", "second", "third" etc. in the present application are not intended to limit the quantity but are used for distinguishing descriptions.

[0084] The present application discloses a high-speed air-floating main shaft, which includes a front air-floating bearing, a rear air-floating bearing, a shell and an inner shaft. The shell is sleeved outside the front air-floating bearing and the rear air-floating bearing, and the shell, the front air-floating bearing and the rear air-floating bearing are surrounded to form a containing space, and the shell is provided with a rear-end driving airway and a front-end driving airway, and the rear-end driving airway and the front-end driving airway are used to pass air into the containing space. The inner shaft is movably installed in the containing space and is located on the inner side of the front air-floating bearing and the rear air-floating bearing. The inner shaft includes a rear-end turbine part, a rod body part and a front-end turbine part which are arranged in sequence, and the rear-end turbine part corresponds to the rear-end driving airway, and the front-end turbine part corresponds to the front-end driving airway. When the rear-end driving airway is ventilated, the airflow drives the rear-end turbine part so that the inner shaft rotates along the first rotation direction. When the front-end driving airway is ventilated, the airflow drives the front-end turbine part so that the inner shaft rotates along the second rotation direction, and the first rotation direction is opposite to the second rotation direction.

[0085] When the rear turbine part and the front turbine part are driven by the airflow, the inner shaft can rotate. The rotation direction of the rear turbine part is opposite to that of the front turbine part, so that the inner shaft can rotate in both directions. The bidirectionally rotating inner shaft can connect processing tools with different rotation directions, thereby improving applicability.

[0086] Some embodiments of the present application will be described below in conjunction with the accompanying drawings. In the absence of conflict, the following embodiments and features in the embodiments may be combined with each other.

[0087] See also Figures 1 to 3 The embodiment of the present application provides a high-speed air-floating spindle 100, which includes a front air-floating bearing 10, a rear air-floating bearing 101, a housing 20, and an inner shaft 30. The housing 20 is sleeved outside the front air-floating bearing 10 and the rear air-floating bearing 101, and the inner shaft 30 is movably installed inside the front air-floating bearing 10 and the rear air-floating bearing 101.

[0088] In some embodiments, see Figures 3 to 5The shell 20 is sleeved on the front air bearing 10 and the rear air bearing 101, and the shell 20 and the front air bearing 10 and the rear air bearing 101 are surrounded to form a receiving space 40. The shell 20 is provided with a rear end driving air duct 202 and a front end driving air duct 201, and the rear end driving air duct 202 and the front end driving air duct 201 are used to pass air into the receiving space 40.

[0089] The inner shaft 30 is movably mounted in the accommodating space 40, and the inner shaft 30 includes a rear turbine part 31, a rod body part 32, and a front turbine part 33 which are arranged in sequence. The rod body part 32 is movably mounted on the inner side of the front air bearing 10 and the rear air bearing 101, that is, it is penetrated in the front air bearing 10 and the rear air bearing 101. The rear turbine part 31 and the front turbine part 33 are not in contact with the front air bearing 10 and the rear air bearing 101, the rear turbine part 31 corresponds to the rear drive airway 202, and the front turbine part 33 corresponds to the front drive airway 201. During operation, when the rear drive airway 202 is ventilated, the front drive airway 201 is not ventilated, and when the front drive airway 201 is ventilated, the rear drive airway 202 is not ventilated, so that the rear drive airway 202 and the front drive airway 201 are switched for use.

[0090] When the rear-end driving airway 202 is ventilated, the airflow drives the rear-end turbine part 31 to rotate along the first rotation direction, and the rear-end turbine part 31 drives the rod body part 32 and the front-end turbine part 33 to rotate along the first rotation direction; when the front-end driving airway 201 is ventilated, the airflow drives the front-end turbine part 33 to rotate along the second rotation direction, and the front-end turbine part 33 drives the rod body part 32 and the rear-end turbine part 31 to rotate along the second rotation direction. The first rotation direction and the second rotation direction are opposite rotation directions, which can enable the high-speed air-floating spindle 100 in the present application to achieve bidirectional rotation, so that the inner shaft 30 can be connected to tools with different rotation directions, thereby improving the applicability of the high-speed air-floating spindle 100.

[0091] Exemplarily, the first rotation direction is clockwise and the second rotation direction is counterclockwise, or the first rotation direction is counterclockwise and the second rotation direction is clockwise.

[0092] It should be noted that the processing tool 200 connected to the inner shaft 30 can be a tool, and the tool has left-hand rotation and right-hand rotation. The forward and reverse rotation of the inner shaft 30 are affected by the tool rotation direction. The right-handed tool is usually connected to the forward rotating inner shaft 30, and the left-handed tool is usually connected to the reverse inner shaft 30. In different processing situations, the rotation direction of the tool suitable for use is also different. Most tools are right-handed. The left-handed milling cutter is generally a tool selected under the demand for high-precision processing. It is suitable for mobile phone button processing, membrane switch panel, LCD panel, acrylic lens and other fine processing. The high-speed air-floating spindle 100 has a fast rotation speed, and the speed generally reaches 100,000 rpm. It is a high-speed spindle. In this case, it is often used for fine processing of workpieces, so a left-handed tool is required. When the high-speed air-floating spindle 100 can rotate in both directions, it can be used for both left-handed tools and right-handed tools, and rough processing and fine processing can be completed by the same high-speed air-floating spindle 100.

[0093] In some embodiments, the rear-end driving airway 202 and the front-end driving airway 201 are connected with a reversing valve, and the reversing valve is connected to an air pump or an air compressor. By operating the reversing valve, the airflow can flow into the rear-end driving airway 202 or into the front-end driving airway 201.

[0094] In some embodiments, the rear turbine part 31 is detachably connected to the rod body part 32, and the front turbine part 33 is integrally formed with the rod body part 32. In some embodiments, the rear turbine part 31 is integrally formed with the rod body part 32, and the front turbine part 33 is detachably connected to the rod body part 32. In some embodiments, both the rear turbine part 31 and the front turbine part 33 are detachably connected to the rod body part 32. The detachable connection can be a screw connection, a threaded connection, a pin connection, a snap-on connection, and the like.

[0095] In some embodiments, see Figures 3 to 5 The housing 20 includes an outer shell 21, a rear end cover 22 and a front end cover 23. The outer shell 21 is in the shape of a cylinder with openings at both ends and is sleeved outside the front air bearing 10 and the rear air bearing 101. The rear end cover 22 and the front end cover 23 are both detachably connected to the outer shell 21 and are disposed at both ends of the outer shell 21. The rear end cover 22 is penetrated to form a rear end driving airway 202. The rear end cover 22 is also provided with a rear air drive air inlet 221 connected to the rear end driving airway 202. The gas enters the rear end driving airway 202 from the rear air drive air inlet 221, then enters the accommodation space 40, and heads toward the rear end turbine section 31. The rear end cover 22 is also penetrated with a front air drive air inlet 222. Along the axial direction of the inner shaft 30, the outer shell 21 is penetrated with a connecting pipe 211. The front air drive air inlet 222 is connected to the connecting pipe 211 to form the front end driving airway 201. The front end cover 23 is used to guide the airflow of the front end driving airway 201 to the front end turbine section 33.

[0096] External air sources such as air pumps and air compressors are connected to the rear drive air duct 202 and the front air drive air inlet 222 on the rear cover 22, so that the overall air intake parts are arranged at the same end of the high-speed air floating main shaft 100, thereby optimizing the arrangement and connection of the pipelines, and also enabling the high-speed air floating main shaft 100 to achieve bidirectional rotation through the same air source.

[0097] In some embodiments, see Figures 3 to 5 The housing 20 also includes a rear drive cover 24, which is arranged between the rear end cover 22 and the shell 21. The rear end annular groove 241 is recessed on the side of the rear drive cover 24 facing the rear end cover 22. The rear end annular groove 241 is connected with the rear end drive airway 202. The rear drive cover 24 is also penetrated by a plurality of rear end inclined holes 242, which are evenly distributed in the rear drive cover 24 in an annular shape. One end of the rear end inclined hole 242 is connected with the rear end annular groove 241, and the other end of the rear end inclined hole 242 faces the rear end turbine part 31, so that the airflow passes through the plurality of rear end inclined holes 242 to drive the rear end turbine part 31.

[0098] A space for accommodating air is formed between the rear end annular groove 241 and the rear end cover 22. The gas enters the rear end annular groove 241 along the rear end driving airway 202, and then enters a plurality of rear end inclined holes 242 connected to the rear end annular groove 241, and is guided to the rear end turbine part 31 through the rear end inclined holes 242. The plurality of rear end inclined holes 242 are distributed in a ring shape, so that the rear end turbine part 31 can be evenly stressed, thereby improving the efficiency and stability of the rotation of the rear end turbine part 31.

[0099] In some embodiments, the rotation axis of the rear end turbine part 31 and the central axis of the multiple rear end inclined holes 242 coincide with each other, so that the airflow derived from the multiple rear end inclined holes 242 can act evenly on the rear end turbine part 31, making the rear end turbine part 31 rotate more smoothly.

[0100] In other embodiments, the rear end annular groove 241 may also be provided on the rear end cover 22 , or the rear end cover 22 and the rear end annular groove 241 may both be provided with the rear end annular groove 241 .

[0101] In other embodiments, the rear end driving air passage 202 on the rear end cover 22 is provided with a plurality of air outlets (not shown), the plurality of air outlets are distributed in an annular manner on the rear end cover 22, and the plurality of air outlets are aligned with the rear end turbine section 31 at the circumference of the rear end turbine section 31. Alternatively, there are a plurality of rear end driving air passages 202, the plurality of rear end driving air passages 202 are distributed in an annular manner on the rear end cover 22, and the air outlets of the plurality of air passages are aligned with the rear end turbine section 31 at the circumference of the rear end turbine section 31.

[0102] In some embodiments, see Figures 3 to 5The shell 20 also includes a front driving cover 25, which is arranged between the front end cover 23 and the shell 21. The front driving cover 25 is recessed with a front end annular groove 251 on the side facing the front end cover 23. The front driving cover 25 is also penetrated by an air hole 252 and a plurality of front end inclined holes 253. The air hole 252 connects the connecting pipe 211 with the front end annular groove 251. The plurality of front end inclined holes 253 are evenly distributed in the front driving cover 25 in a ring shape. One end of the front end inclined hole 253 is connected with the front end annular groove 251, and the other end of the front end inclined hole 253 faces the front end turbine part 33.

[0103] The air enters the connecting pipe 211 from the front air drive air inlet 222, and then enters the front annular groove 251 through the air hole 252. Since the front cover 23 covers the front annular groove 251, a space that can accommodate air is formed between the front annular groove 251 and the front cover 23, and the air entering the front annular groove 251 can be guided to enter the plurality of front inclined holes 253. The airflow enters the plurality of front inclined holes 253 and is guided to the front turbine part 33 through the front inclined holes 253. The front drive cover 25 and the plurality of front inclined holes 253 are arranged so that there are a plurality of positions on the circumference of the front turbine part 33 with airflow that drives the front turbine part 33 to rotate, so that the front turbine part 33 is evenly stressed, and the efficiency and stability of the rotation are improved.

[0104] In some embodiments, the rotation axis of the front turbine section 33 and the central axis of the plurality of front inclined holes 253 are coincident, so that the airflow derived from the plurality of front inclined holes 253 can act evenly on the front turbine section 33, making the front turbine section 33 rotate more smoothly. In some embodiments, the rotation axis of the front turbine section 33 and the rear turbine section 31 are coincident.

[0105] In other embodiments, the front annular groove 251 may also be provided on the front end cover 23 , or both the front end cover 23 and the third end cover are provided with the front annular groove 251 .

[0106] In other embodiments, an air pipe connected to the connecting pipe 211 may be directly provided on the front end cover 23 to guide the airflow to the front end turbine part 33 .

[0107] In some embodiments, see Figure 6 and Figure 7 A plurality of arc-shaped grooves 301 are provided on the periphery of the rear end turbine part 31 , and the airflow passing through the rear end inclined hole 242 impacts the groove wall of the arc-shaped groove 301 , thereby driving the rear end turbine part 31 to rotate.

[0108] In some embodiments, see Figure 6 and Figure 7Along the axial direction of the inner shaft 30, the groove walls at both ends of the arc groove 301 penetrate, so that an arc blade 302 is formed between two adjacent arc grooves 301 of the rear end turbine part 31. The arc blades 302 are distributed in a ring shape to form a turbine structure. The gas can flow out from the groove walls penetrated at both ends of the arc groove 301, which can make the rotation efficiency higher and the rotation smoother.

[0109] In some embodiments, see Figure 6 and Figure 7 The rear end inclined hole 242 is set as an inclined hole, and the inclined hole cooperates with the arc blade 302 with a turbine structure to guide the airflow and impact the concave side of the arc blade 302, so that the arc blade 302 can rotate faster and more smoothly, thereby improving the rotation efficiency and stability of the rear end turbine part 31.

[0110] The arc radius of the arc blade 302 and the inclination angle of the rear end inclined hole 242 have an impact on the rotation efficiency and rotation stability of the rear end turbine part 31. For example, the radius of the rear end turbine part 31 is 18mm-22mm. Figure 6 and Figure 7 , along the bending direction of the arc blade 302, the arc radius R1 of the outer side of the arc blade 302 is set between 5mm-5.5mm, and R1 can be 5mm, 5.1mm, 5.2mm, 5.3mm, 5.4mm, 5.5mm, etc. Along the bending direction of the arc blade 302, the inner arc radius R2 of the arc blade 302 is set between 7mm-7.5mm, and R2 can be 7mm, 7.1mm, 7.2mm, 7.3mm, 7.4mm, 7.5mm, etc. The angle α between the rear end inclined hole 242 and the axial direction of the inner shaft 30 is set between 70°-75°, and the angle α can be 70°, 71°, 72°, 73°, 74°, 75°, etc. According to the above-mentioned arc radius of the arc blade 302 and the inclination angle of the rear end inclined hole 242, the rotation efficiency and rotation stability of the rear end turbine part 31 can be greatly improved.

[0111] In some embodiments, a plurality of arcuate grooves 301 are provided on the periphery of the front turbine part 33, and the airflow impacts the groove wall of the arcuate groove 301 through the front inclined hole 253, thereby driving the front turbine part 33 to rotate. The arcuate grooves 301 on the front turbine part 33 and the arcuate grooves 301 on the rear turbine part 31 have opposite bending directions, so that the rotation direction of the rear turbine part 31 when driven by the airflow is opposite to the rotation direction of the front turbine part 33 when driven by the airflow.

[0112] In some embodiments, the arcuate groove 301 on the front turbine part 33 penetrates the groove wall at both ends of the inner shaft 30 in the axial direction to form an arcuate blade 302. The arrangement of the arcuate blade 302 on the front turbine part 33 and the inclination angle of the front inclined hole 253 can refer to the arrangement of the arcuate blade 302 on the rear turbine part 31 and the inclination angle of the rear inclined hole 242, which will not be described in detail here. The arcuate blade 302 on the front turbine part 33 is bent in the opposite direction to the arcuate blade 302 on the rear turbine part 31, so that the rotation direction of the rear turbine part 31 when driven by the airflow is opposite to the rotation direction of the front turbine part 33 when driven by the airflow.

[0113] In other embodiments, annularly distributed blades (not shown) are directly provided on the periphery of the rear end turbine portion 31 and the front end turbine portion 33, and the width direction of the blades is parallel to the axial direction of the inner shaft 30. The rear end inclined hole 242 and the air hole 252 are both configured as inclined holes so that the airflow impacts the surface of the blades along the width direction, causing the rear end turbine portion 31 and the front end turbine portion 33 to rotate.

[0114] In some embodiments, see Figure 8 A connecting portion 35 is provided on the side of the front turbine portion 33 facing away from the rod body portion 32, and the connecting portion 35 can be used to connect components such as a grinding wheel and a milling cutter to process the tool 200.

[0115] In some embodiments, see Figure 8 The housing 20 is provided with an air-floating bearing air supply passage 26. Specifically, the rear end cover 22 is provided with an air-floating air inlet 261. The rear end cover 22, the rear drive cover 24 and the housing 21 are penetrated with corresponding communicating channels corresponding to the air-floating air inlet 261 to form the air-floating bearing air supply passage 26. There is a gap between the front air-floating bearing 10, the rear air-floating bearing 101 and the inner shaft 30. The front air-floating bearing 10 and the rear air-floating bearing 101 are respectively penetrated with a plurality of radial air holes 11 along their radial directions. The plurality of radial air holes 11 on the front air-floating bearing 10 are arranged in a ring shape along the circumference of the front air-floating bearing 10, and the plurality of radial air holes 11 on the rear air-floating bearing 101 are arranged in a ring shape along the circumference of the rear air-floating bearing 101. Each radial air hole 11 is connected to the air-floating bearing air supply passage 26. Air enters the plurality of radial air holes 11 through the air bearing air supply passage 26, thereby forming an air film between the front air bearing 10, the rear air bearing 101 and the inner shaft 30. The air film is between the outer circumference of the inner shaft 30 and the front air bearing 10, and between the outer circumference of the inner shaft 30 and the rear air bearing 101, so that the inner shaft 30 can rotate freely inside the front air bearing 10 and the rear air bearing 101. The air film can replace the rolling contact of ordinary bearings, thereby reducing friction, reducing friction loss when the inner shaft 30 rotates, and improving rotation efficiency.

[0116] In some embodiments, see Fig. 9 and Fig.10 Along the circumference of the front air bearing 10, a bearing annular groove 14 is provided on the outer peripheral wall of the front air bearing 10, the central axis of the bearing annular groove 14 coincides with the central axis of the front air bearing 10, and the radial air holes 11 are all provided in the bearing annular groove 14. The air bearing air supply channel 26 is connected with the bearing annular groove 14, so that the air bearing air supply channel 26 can be connected with all radial air holes 11 at the same time, which is conducive to simplifying the structure of the air bearing air supply channel 26.

[0117] In some embodiments, each front air bearing 10 is provided with a plurality of bearing annular grooves 14, which are arranged at intervals and connected through axial grooves 15. The extension direction of the axial grooves 15 is flush with the axial direction of the front air bearing 10. The plurality of bearing annular grooves 14 allow the radial air holes 11 to be arranged along the circumferential direction of the front air bearing 10, and can also be arranged along the axial direction of the front air bearing 10. A connected space that can accommodate air is formed between the bearing annular grooves 14, the axial grooves 15 and the housing 21. The air supply channel 26 of the air bearing is connected to one of the bearing annular grooves 14, so that air can be filled between all the bearing annular grooves 14 and the axial grooves 15. Each bearing annular groove 14 is evenly distributed with a plurality of radial air holes 11. Air enters the plurality of radial air holes 11, and then fills between the inner shaft 30 and the front air bearing 10, so that an air film is formed between the circumferential side of the inner shaft 30 and the front air bearing 10. The annular groove and the axial groove 15 allow an air bearing air supply channel 26 to be connected to multiple radial air holes 11 at the same time. The multiple radial air holes 11 are arranged along the circumference of the front air bearing 10 and are also arranged along the axial direction of the front air bearing 10, which can make the inflation uniform, improve the uniformity of the air film thickness, and reduce the risk of the inner shaft 30 deviating to one side.

[0118] In some embodiments, please refer to Fig. 9 and Fig.10 The rear air bearing 101 is provided with a bearing annular groove 14 and an axial groove 15. The specific arrangement and beneficial effects can refer to the description of the arrangement of the bearing annular groove 14 and the axial groove 15 of the front air bearing 10, which will not be repeated here.

[0119] In other embodiments, a plurality of air bearing air supply channels 26 may be provided, the number of air bearing air supply channels 26 is equal to the number of radial air holes 11 , and each air bearing air supply channel 26 is connected to a radial air hole 11 .

[0120] In some embodiments, see Figures 8 to 10The outer diameters of the rear turbine section 31 and the front turbine section 33 are both larger than the outer diameter of the rod body section 32. The front air bearing 10 and the rear air bearing 101 are arranged between the rear turbine section 31 and the front turbine section 33. There is a gap between the front air bearing 10, the rear air bearing 101 and the rear turbine section 31, and there is also a gap between the front air bearing 10, the rear air bearing 101 and the front turbine section 33. The rear air bearing 101 is penetrated by a rear axial air hole 12, and the front air bearing 10 is penetrated by a front axial air hole 13. The air inlet end of the rear axial air hole 12 is connected to the air supply passage 26 of the air bearing, and the air outlet end of the rear axial air hole 12 faces the rear turbine section 31. The air inlet end of the front axial air hole 13 is connected to the air supply passage 26 of the air bearing, and the air outlet end of the front axial air hole 13 faces the front turbine section 33. Air enters the rear axial air hole 12 from the air bearing air supply passage 26, and is then discharged from the air outlet end of the rear axial air hole 12, so that an air film is formed between the rear end turbine part 31 and the rear air bearing 101; at the same time, air enters the front axial air hole 13 from the air bearing air supply passage 26, and is then discharged from the air outlet end of the front axial air hole 13, so that an air film is formed between the front end turbine part 33 and the front air bearing 10, so that both ends of the inner shaft 30 in the axial direction are supported by the air film, making the rotation of the inner shaft 30 more efficient and stable.

[0121] In some embodiments, see Fig. 9 and Fig.10 , there are multiple rear axial air holes 12 and multiple front axial air holes 13, and the air inlet ends of the rear axial air holes 12 and the air inlet ends of the front axial air holes 13 are both connected to the bearing annular groove 14. Specifically, the rear axial air holes 12 are opened on the side wall of the bearing annular groove 14 on the rear air-floating bearing 101 adjacent to the rear end turbine part 31, and the front axial air holes 13 are opened on the side wall of the bearing annular groove 14 on the front air-floating bearing 10 adjacent to the front end turbine part 33, so that one air-floating bearing air supply passage 26 can simultaneously connect multiple rear axial air holes 12 and multiple front axial air holes 13. In some embodiments, along the circumference of the rear air-floating bearing 101, multiple rear axial air holes 12 are arranged in a ring shape on the rear air-floating bearing 101, and along the circumference of the front air-floating bearing 10, multiple front axial air holes 13 are arranged in a ring shape on the front air-floating bearing 10.

[0122] In some embodiments, see Fig. 9 and Fig.10The outer peripheral wall of the rear air bearing 101 is provided with a rear air-filling groove 16, the outer peripheral wall of the front air bearing 10 is provided with a front air-filling groove 17, the rear axial air hole 12 is connected with the rear air-filling groove 16, and the front axial air hole 13 is connected with the front air-filling groove 17. The extension direction of the rear air-filling groove 16 and the front air-filling groove 17 is flush with the axial direction of the front air bearing 10, which can increase the volume of the air supply chamber of the rear axial air hole 12 and the front axial air hole 13, and is used to homogenize the pressure distribution in the air chamber, so that each rear axial air hole 12 and the front axial air hole 13 can obtain a stable and balanced air flow supply.

[0123] In some embodiments, see Fig. 9 The housing 20 further includes a rear gasket 27 and a front gasket 28. The rear gasket 27 is arranged between the housing 21 and the rear drive cover 24, and the front gasket 28 is arranged between the housing 21 and the front drive cover 25. The rear turbine part 31 is located inside the rear gasket 27, and the front turbine part 33 is located inside the front gasket 28. In view of the large outer diameters of the rear turbine part 31 and the front turbine part 33, the rear turbine part 31 or the front turbine part 33 can be connected to the rod body part 32 first, and then the rear gasket 27 and the front gasket 28 are installed, thereby facilitating the installation of the rear turbine part 31 or the front turbine part 33. It should be noted that the rear gasket 27 is provided with an avoidance structure or a through-hole structure to keep the connecting pipe 211 and the air hole 252 connected, or to allow the gas in the air flotation air inlet 261 to flow into the bearing annular groove 14. The front gasket 28 is also provided with an avoidance structure or a through-hole structure to keep the front air drive air inlet 222 and the connecting pipe 211 connected.

[0124] In some embodiments, see Fig.11 The housing 21 is provided with a rear exhaust passage 212 and a front exhaust passage 213. A plurality of exhaust ports 271 are provided in the circumferential direction of the rear gasket 27. The air inlet end of the rear exhaust passage 212 is communicated with the inner side of the rear gasket 27, and the exhaust end of the rear exhaust passage 212 is communicated with the exhaust port 271 to discharge the airflow driving the rear turbine section 31. The air inlet end of the front exhaust passage 213 is communicated with the inner side of the front gasket 28, and the exhaust end of the front exhaust passage 213 is communicated with the exhaust port 271 to discharge the airflow driving the front turbine section 33. The exhaust ports 271 are all provided in the rear gasket 27, so that the exhaust position is located at the same position in the axial direction of the housing 20.

[0125] When the high-speed air-floating spindle 100 of the present application is working, when the inner shaft 30 is required to drive the processing tool 200 to rotate along the first rotation direction, the rear drive air channel 202 is ventilated, and the front drive air channel 201 is not ventilated. The airflow enters the rear annular groove 241 from the rear drive air channel 202, and then enters the multiple rear inclined holes 242. After passing through the multiple rear inclined holes 242, the airflow drives the rear turbine part 31 to rotate along the first rotation direction, and the inner shaft 30 rotates along the first rotation direction. When the inner shaft 30 is required to drive the processing tool 200 to rotate along the second rotation direction, the front drive air channel 201 is ventilated, and the rear drive air channel 202 is not ventilated. The airflow enters the air hole 252 from the front drive air channel 201, and then enters the front annular groove 251, and then enters the multiple front inclined holes 253. After passing through the multiple front inclined holes 253, the airflow drives the front turbine part 33 to rotate along the second rotation direction. By switching the ventilation states of the rear-end driving airway 202 and the front-end driving airway 201 , the inner shaft 30 can rotate bidirectionally. The bidirectionally rotating inner shaft 30 can be connected to processing tools 200 with different rotation directions, thereby improving applicability.

[0126] In addition, those skilled in the art should recognize that the above embodiments are only used to illustrate the present application, and are not intended to limit the present application. As long as they are within the spirit of the present application, appropriate changes and modifications to the above embodiments are within the scope of the present application.

Claims

1. A high-speed air-floating spindle, characterized in that: It includes a front air bearing, a rear air bearing, a housing and an inner shaft; wherein, The front air bearing and the rear air bearing are arranged at intervals along the axial direction of the inner shaft, and along the circumferential direction of the front air bearing and the rear air bearing, the outer peripheral walls of the front air bearing and the rear air bearing are both provided with bearing annular grooves, and a plurality of radial air holes are penetrated in the bearing annular grooves; The shell comprises an outer shell, a front end cover, a rear end cover, a front drive cover and a rear drive cover, the outer shell is sleeved outside the front air floating bearing and the rear air floating bearing, the front end cover and the rear end cover are respectively arranged at two ends of the inner shaft, the rear end cover is penetrated to form a rear end drive air passage, the rear end cover is also penetrated with a front air drive air inlet and a rear air drive air inlet connected with the rear end drive air passage, the outer shell is penetrated with a connecting pipe along the axial direction of the inner shaft, the front air drive air inlet is connected with the connecting pipe to form the front end drive air passage; The inner shaft comprises a rear turbine part, a rod body part and a front turbine part which are arranged in sequence, the two ends of the rod body part are inserted into the front air bearing and the rear air bearing, and the outer diameters of the rear turbine part and the front turbine part are both larger than the outer diameter of the rod body part; The rear drive cover is arranged between the rear end cover and the housing, a rear end annular groove is recessed on one side of the rear drive cover facing the rear end cover, the rear end annular groove is communicated with the rear end drive airway, the rear drive cover is also penetrated by a plurality of rear end inclined holes, the plurality of rear end inclined holes are distributed in an annular shape on the rear drive cover, the rear end inclined holes are used to guide the gas in the rear end annular groove to the rear end turbine part; The front driving cover is arranged between the front end cover and the housing, the front driving cover is provided with a front end annular groove on one side facing the front end cover, the front driving cover is also provided with an air hole and a plurality of front end inclined holes, the air hole connects the front end driving airway with the front end annular groove, the plurality of front end inclined holes are evenly distributed in the front driving cover in an annular shape, and the front end inclined hole is used to guide the gas in the front end annular groove to the front end turbine part; The rear end cover is also provided with an air-floating air inlet, and the rear end cover, the rear drive cover and the housing are sequentially penetrated corresponding to the air-floating air inlet to form an air-floating bearing air supply passage, and the air-floating bearing air supply passage is connected with the bearing annular grooves of the front air-floating bearing and the rear air-floating bearing; The rear air-floating bearing is provided with a rear axial air hole, the air inlet end of the rear axial air hole is connected with the bearing annular groove, and the air outlet end of the rear axial air hole faces the rear end turbine part; the front air-floating bearing is provided with a front axial air hole, the air inlet end of the front axial air hole is connected with the bearing annular groove, and the air outlet end of the front axial air hole faces the front end turbine part; The air enters the rear axial air hole from the air supply passage of the air floating bearing and is discharged from the air outlet end of the rear axial air hole, so that an air film is formed between the rear end turbine part and the rear air floating bearing; the air enters the front axial air hole from the air supply passage of the air floating bearing and is discharged from the air outlet end of the front axial air hole, so that an air film is formed between the front end turbine part and the front air floating bearing; When the rear end drives airway ventilation, the airflow drives the rear end turbine part to rotate the inner shaft along a first rotation direction. When the front end drives airway ventilation, the airflow drives the front end turbine part to rotate the inner shaft along a second rotation direction. The first rotation direction is opposite to the second rotation direction.

2. The high-speed air-floating spindle according to claim 1, characterized in that: The outer peripheral wall of the rear air bearing is provided with a rear air filling groove, which is communicated with the rear axial air hole. The front air bearing is provided with a front air filling groove, which is communicated with the front axial air hole.

3. The high-speed air-floating spindle according to claim 1, characterized in that: The front air bearing is provided with a plurality of annular bearing grooves, the plurality of annular bearing grooves are arranged at intervals along the axial direction of the front air bearing, an axial groove is further provided on the outer peripheral wall of the front air bearing, and the plurality of annular bearing grooves are connected through the axial groove; and / or, The rear air bearing is provided with a plurality of annular bearing grooves, which are arranged at intervals along the axial direction of the rear air bearing. An axial groove is also provided on the outer peripheral wall of the rear air bearing, and the plurality of annular bearing grooves are connected through the axial groove.

4. The high-speed air-floating spindle according to claim 1, characterized in that: The rotation axis of the front turbine part, the rotation axis of the rear turbine part, the central axes of the multiple front inclined holes and the central axes of the multiple rear inclined holes all coincide, and the front air drive air inlet and the air floating air inlet are symmetrically arranged according to the central axes of the multiple rear inclined holes.

5. The high-speed air-floating spindle according to claim 1, characterized in that: A connecting portion for connecting a processing tool is provided on a side of the front turbine portion facing away from the rod body portion.

6. The high-speed air-floating spindle according to claim 1, characterized in that: A plurality of arc grooves are arranged on the peripheries of the rear end turbine part and the front end turbine part.

7. The high-speed air-floating spindle according to claim 6, characterized in that: Along the axial direction of the inner shaft, the groove walls at both ends of the arc-shaped groove penetrate, so that arc-shaped blades are formed between any two adjacent arc-shaped grooves of the rear end turbine part and between any two arc-shaped grooves of the front end turbine part.

8. The high-speed air-floating spindle according to claim 7, characterized in that: The radii of the rear end turbine part and the front end turbine part are set to 18mm-22mm. Along the bending direction of the arc blade, the arc radius R1 of the outer side of the arc blade is set to 5mm-5.5mm, and the arc radius R2 of the inner side of the arc blade is set to 7mm-7.5mm.

9. The high-speed air-floating spindle according to claim 1, characterized in that: The shell also includes a rear end gasket and a front end gasket, the rear end gasket is arranged between the outer shell and the rear drive cover, the front end gasket is arranged between the outer shell and the front drive cover, the rear end turbine part is located on the inner side of the rear end gasket, and the front end turbine part is located on the inner side of the front end gasket.

10. The high-speed air-floating spindle according to claim 9, characterized in that: The outer shell is provided with a rear end exhaust duct and a front end exhaust duct, and a plurality of exhaust ports are provided in the circumference of the rear end gasket. The air inlet end of the rear end exhaust duct is connected to the inner side of the rear end gasket, and the exhaust end of the rear end exhaust duct is connected to the exhaust port. The air inlet end of the front end exhaust duct is connected to the inner side of the front end gasket, and the exhaust end of the front end exhaust duct is connected to the exhaust port.

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