CN101774031B - Ultrahigh speed precise pneumatic micro spindle unit - Google Patents

Abstract

Ultra-high-speed precision pneumatic micro-spindle unit, including: main shaft, turbine, front-end gas bearing, rear-end gas bearing, box body, miniature elastic coupling, shape memory alloy jacket, execution shaft, execution shaft gas bearing, on the main shaft The turbine is provided, and is supported and installed in the shaft hole of the box body through the front end gas bearing and the rear end gas bearing; the front end of the main shaft is provided with an axial hole and a miniature elastic coupling; the The execution shaft is supported and installed in the shaft hole of the box through the gas bearing of the execution shaft, and one end of it is installed in the axial hole of the main shaft; the shape memory alloy jacket is installed on the outer circumference of the front end of the main shaft On the top, the execution shaft is clamped on the main shaft; the invention has reasonable structure, simple manufacturing process, high speed, small runout error, is suitable for industrial production, and can be used as a micro-spindle of a micro-cutting machine tool and other high-speed, ultra-high-speed, high-precision Rotary kinematic electromechanical devices or micro-spindle units for hand tool machines.

Description

Ultra-high-speed precision pneumatic micro-spindle unit

technical field

The invention discloses an ultra-high-speed precision pneumatic micro-spindle unit, which belongs to the technical field of mechanical manufacturing.

Background technique

The miniaturization of parts and the high precision of size have put forward higher and higher requirements for its processing equipment. At present, the maximum speed of the micro electric spindle used on the micro machine tool or manual machine tool is generally not more than 300,000rpm, and with the increase of the speed, the heat generation continues to increase, resulting in deformation of the spindle, which seriously affects the processing quality of the parts. In addition, the existing pneumatic micro-spindle has low speed, weak load capacity, low rigidity, and large runout error, which is difficult to meet the requirements of high-speed/ultra-high-speed micro-milling, micro-drilling, micro-grinding and other micro-cutting processing requirements for micro-small parts.

Contents of the invention

The purpose of the present invention is to overcome the existing deficiencies and provide an ultra-high-speed precision pneumatic micro-spindle unit with reasonable structure, simple manufacturing process, high speed and small run-out error, so as to meet the requirements of the manufacturing industry for ultra-high-speed, low-run-out error micro-spindles. demand.

To achieve the above object, the present invention adopts the following technical solutions:

Ultra-high-speed precision pneumatic micro-spindle unit, including: main shaft, turbine, front-end gas bearing, rear-end gas bearing, box body, miniature elastic coupling, shape-memory alloy jacket, execution shaft, execution shaft gas bearing, the front end of the main shaft The front end gas bearing and the rear end are supported and installed in the shaft hole of the box body through the rear end gas bearing; a turbine chamber is arranged between the front end gas bearing and the rear end gas bearing, and the The turbine is arranged on the main shaft and in the turbine chamber; the front end gas bearing and the rear end gas bearing are respectively composed of at least one static pressure gas radial bearing and one static pressure gas thrust bearing; the main shaft The front end is provided with an axial hole and a miniature elastic coupling; the execution shaft is supported and installed in the shaft hole of the box through the gas bearing of the execution shaft, and one end is installed in the axial hole provided at the front end of the main shaft The shape memory alloy jacket is installed on the outer circumference of the front end of the main shaft to clamp the execution shaft in the main shaft; the gas bearing of the execution shaft is composed of at least one static pressure gas radial bearing.

In the present invention, the main shaft is integrated with the turbine.

In the present invention, the rear end surface of the main shaft is symmetrically provided with two holes or grooves along the axis of the main shaft.

In the present invention, the box body is equipped with a rear cover, and the eddy current sensor is installed on the rear cover, and its installation position corresponds to the position of the hole or groove provided on the rear end surface of the main shaft.

In the present invention, the air inlets of the front gas bearing, the rear air bearing, the air bearing of the execution shaft and the turbine chamber are respectively provided on the box body.

In the present invention, the exhaust groove of the turbine chamber is arranged on the rear cover of the box body.

In the present invention, the air outlets of the front end gas bearing, the rear end gas bearing and the execution shaft gas bearing are respectively provided on the box body.

In the present invention, a cap is installed at one end of the main shaft, a cavity is formed between the cap and the gas bearing of the execution shaft, and the shape memory alloy jacket is located in the cavity.

In the present invention, a bushing is installed between the execution shaft and the gas bearing of the execution shaft.

In the present invention, at least one group of micro-cut grooves is arranged on the miniature elastic coupling, and the group of micro-cut grooves is composed of two pairs of mutually perpendicular micro-cut grooves, and each pair of micro-cut grooves is perpendicular to the The axis of the coupling is symmetrically arranged on the coupling; the center of the coupling is provided with an axial hole.

Due to the adoption of the above-mentioned structure, the present invention utilizes the turbine chamber air inlet and the exhaust groove provided on the casing to realize the high-speed drive of the turbine main shaft, and the rotating speed is high; the bearing composed of the static pressure gas radial bearing and the static pressure gas thrust bearing is used The pair supports and positions the main shaft at the front end of the main shaft and the rear end of the main shaft, which can effectively reduce the friction loss and runout error of the main shaft when the main shaft rotates at high speed; the manufacturing error and installation error, runout error, etc., so that the turbine spindle can achieve zero error transmission speed and torque; the use of static pressure gas radial bearings to support the execution shaft can effectively improve the rotation accuracy of the execution shaft, and meet the high rotation accuracy requirements of the micro-spindle unit at ultra-high speed; The execution shaft is clamped in the main shaft by shape memory alloy, and the bushing is installed in the gas bearing of the execution shaft. It is convenient to change the loosening and clamping state of the shape memory alloy jacket by changing the temperature in the cap, which is convenient. The installation, maintenance and replacement of the execution shaft; the real-time measurement of the spindle speed is realized by using the eddy current sensor installed on the back cover and the two holes or slots on the rear end of the spindle.

In summary, the present invention has reasonable structure, simple manufacturing process, high rotating speed, small runout error, safety and reliability, and if the execution shaft is a micro-tool, it is especially suitable for high-speed/ultra-high-speed micro-milling, micro-drilling, micro-drilling, Micro-grinding and other micro-cutting processing; suitable for industrial production, it can be used as the micro-spindle of micro-cutting machine tools and other electromechanical equipment for high-speed ultra-high-speed, high-precision rotary motion or micro-spindle unit of manual tool machines.

Description of drawings

Accompanying drawing 1 is the main sectional view of the embodiment of the present invention.

Accompanying drawing 2 is A-A sectional view of Fig. 1.

Accompanying drawing 3 is the schematic diagram of the structure of the miniature elastic coupling in the present invention.

In the attached drawings: 1--eddy current sensor, 2--rear cover, 3--rear end gas bearing, 4--box, 5--turbine chamber, 6--air inlet of gas bearing, 7--front end Gas bearing, 8--front end axial hole, 9--cap, 10--baffle, 11--execution shaft gas bearing bushing, 12--execution shaft, 13--shape memory alloy jacket, 14- -Executive shaft gas bearing, 15--cross-cut groove, 16--longitudinal cut groove, 17-coupling axial hole, 18--turbine, 19--main shaft, 20--hole or groove, 21--exhaust Groove, 22---turbine chamber air inlet, 23---miniature elastic coupling.

Detailed ways

Below in conjunction with embodiment and accompanying drawing, the present invention is described in detail:

Referring to accompanying drawings 1, 2, and 3, the ultra-high-speed precision pneumatic micro-spindle unit of the present invention includes:

1--Eddy current sensor, 2--Back cover, 3--Rear end gas bearing, 4--Case body, 5--Turbine chamber, 6--Gas bearing air inlet, 7--Front end gas bearing, 9 --cap, 10--baffle, 11--execution shaft gas bearing bushing, 12--execution shaft, 13--shape memory alloy jacket, 14--execution shaft gas bearing, 18--turbine, 19 --main shaft, 20--hole or groove, 21--exhaust groove, 22--turbine chamber air inlet, 23--miniature elastic coupling, the rear end face of the main shaft 19 is arranged symmetrically along the axis of the main shaft 19 There are two holes or grooves 20; the eddy current sensor 1 is installed on the rear cover 2, and its installation position corresponds to the positions of the two holes or grooves 20 provided on the rear end surface of the main shaft 19; The front end gas bearing 7, the rear end gas bearing 3, the air inlet 6 and the exhaust port of the execution shaft gas bearing 14 are provided; the front end of the main shaft 19 passes through the front end gas bearing 7, and the rear end passes through the rear end The gas bearing 3 is supported and installed in the shaft hole of the box body 4; the box body 4 is equipped with a rear cover 2 for installing the eddy current sensor 1; between the front end gas bearing 7 and the rear end gas bearing 3 The turbine chamber 5 is arranged between, and the turbine 18 is arranged on the main shaft 19 and in the turbine chamber 5; the casing 4 is provided with the air inlet 22 of the turbine chamber 5, and The back cover 2 is provided with the exhaust groove 21 of the turbine chamber 5; the front end gas bearing 7 and the rear end gas bearing 3 are respectively composed of a static pressure gas radial bearing and a static pressure gas thrust bearing Composition; the front end of the main shaft 19 is provided with a miniature elastic coupling 23 and an axial hole 8; the execution shaft 12 is installed in the shaft hole of the box body 4 through the execution shaft gas bearing 14, and one end is installed in the In the axial hole 8 provided at the front end of the main shaft 19, a bushing 11 is installed between the execution shaft 12 and the gas bearing 14 of the execution shaft; the shape memory alloy jacket 13 is installed at the front end of the main shaft 19 On the outer circumference of the shaft, the execution shaft 12 is clamped in the main shaft 19; one end of the main shaft 19 is equipped with a cap 9, and a cavity is formed between the cap 9 and the gas bearing 12 of the execution shaft , the shape memory alloy jacket 13 is in the cavity; the execution shaft gas bearing 14 is composed of a static pressure gas radial bearing.

The micro-elastic coupling 23 is provided with at least one group of micro-cut grooves, and the group of micro-cut grooves is composed of two pairs of mutually perpendicular micro-cut grooves 15, 16, and each pair of micro-cut grooves 15, 16 It is perpendicular to the axis of the miniature elastic coupling 23 and arranged symmetrically on the miniature elastic coupling 23 ; the center of the miniature elastic coupling 23 is provided with an axial hole 17 .

In this embodiment, the main shaft 19 and the turbine 18 are integrally made.

The working principle of the present invention is briefly described as follows: the gas source enters the rear end gas bearing 3 through the air inlet 6 to drive the static pressure gas radial bearing at the rear end of the main shaft and the static pressure gas thrust bearing at the rear end of the main shaft and the static pressure gas diameter at the front end of the main shaft Bearings and static pressure gas thrust bearings support and locate the main shaft, which can effectively reduce the friction loss and runout error when the main shaft rotates at high speed; the air source enters the turbine chamber 5 through two air inlets 22, and drives the turbine main shaft to rotate at high speed, and then Drive the tool clamped by the central axial hole set at the front end of the spindle to realize the machining of the workpiece. The invention adopts miniature elastic couplings to compensate the manufacturing error, installation error and jump error of the turbine main shaft, so that the turbine main shaft can transmit the speed and torque with zero error; the execution shaft is supported by gas bearings, and the rotation accuracy is high; the shape memory is adopted The alloy jacket clamps the end of the execution shaft, and a bush is added in the gas bearing of the execution shaft to meet the replaceable requirements of the execution shaft.

Claims (10)

1. ultrahigh speed precise pneumatic micro spindle unit, comprise: main shaft, turbine, front end gas bearing, rear end gas bearing, casing, miniature elastic coupling, marmem chuck, execution axle, an execution axle gas bearing is characterized in that: described front-end of spindle is installed in the axis hole of described casing by the supporting of described rear end gas bearing by described front end gas bearing, rear end; Be provided with turbine room between described front end gas bearing and rear end gas bearing, described turbine is arranged on the described main shaft and is in the described turbine room; Described front end gas bearing, described rear end gas bearing are made up of at least one pressurized air journal bearing and a pressurized air thrust bearing respectively; Described front-end of spindle is provided with axial hole and miniature elastic coupling; Described execution axle is installed in the axis hole of described casing by the supporting of described execution axle gas bearing, and the one end is installed in the axial hole of described front-end of spindle setting; Described marmem chuck is installed on the excircle of described front-end of spindle, and described execution axle clamp is held in the described main shaft; Described execution axle gas bearing is made up of at least one pressurized air journal bearing.

2. ultrahigh speed precise pneumatic micro spindle unit according to claim 1 is characterized in that: described main shaft and turbine are made one.

3. ultrahigh speed precise pneumatic micro spindle unit according to claim 2 is characterized in that: described rear-end of spindle face is arranged with two holes or groove along described main-shaft axis.

4. ultrahigh speed precise pneumatic micro spindle unit according to claim 3 is characterized in that: described casing is equipped with bonnet, on the described bonnet current vortex sensor is installed, and its installation site is corresponding with hole or groove position that described rear-end of spindle face is provided with.

5. ultrahigh speed precise pneumatic micro spindle unit according to claim 4 is characterized in that: be respectively equipped with described front end gas bearing, rear end gas bearing on the described casing, carry out the air inlet of axle gas bearing and the air inlet of described turbine room.

6. ultrahigh speed precise pneumatic micro spindle unit according to claim 5 is characterized in that: the bonnet of described casing is provided with the air discharge duct of described turbine room.

7. ultrahigh speed precise pneumatic micro spindle unit according to claim 6 is characterized in that: the exhaust outlet that is respectively equipped with described front end gas bearing, rear end gas bearing, execution axle gas bearing on the described casing.

8. ultrahigh speed precise pneumatic micro spindle unit according to claim 7, it is characterized in that: an end of described main shaft is equipped with and emits lid, described emitting between lid and the described execution axle gas bearing forms a cavity, and described marmem chuck is in the described cavity.

9. ultrahigh speed precise pneumatic micro spindle unit according to claim 8 is characterized in that: between described execution axle and the described execution axle gas bearing lining is installed.

10. ultrahigh speed precise pneumatic micro spindle unit according to claim 9, it is characterized in that: described miniature elastic coupling is provided with at least one group of little grooving, described each organize little grooving and form by two pairs of orthogonal little groovings, described each to little grooving perpendicular to described shaft coupling axis and be symmetricly set on the described shaft coupling; Described shaft coupling center is provided with axial hole.

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