CN104475874B - A gear ultrasonic precision gear hobbing device and its application - Google Patents

Abstract

The invention belongs to gear ultrasonic finishing technology field, be specifically related to the ultrasonic accurate hobbing device of a kind of gear and application.The problems such as present invention mainly solves the cutting hobbing power in hardened face gear hobbing processes, heat in metal cutting big, hob abrasion is serious, and hobboing cutter service life is relatively low.The ultrasonic accurate hobbing device of one gear of the present invention is turned round by gear workpieces and supersonic vibration composite main shaft system, outer support fixed system and ultrasonic power exchange system three part composition.The application of the ultrasonic accurate hobbing device of a kind of gear of the present invention is to be arranged on the workbench of gear hobbing ultrasonic for gear accurate hobbing device, different structure feature according to gear workpieces uses different supersonic vibration modes and hobboing cutter feeding cutting way to realize ultrasonic accurate gear hobbing, hobboing cutter service life can be extended, improve tooth-face roughness, improve gear hobbing process precision, improve flank of tooth micro cutting texture, reduce noise, improve the purpose of wearability.

Description

A gear ultrasonic precision hobbing device and its application

technical field

The invention belongs to the technical field of ultrasonic finishing of gears, and in particular relates to an ultrasonic precision gear hobbing device and its application.

Background technique

The development of new gear manufacturing technology is largely reflected in the improvement of production efficiency and precision level. At present, power transmission gears at home and abroad are developing in the direction of heavy load, high speed, high precision and high efficiency, and strive for low noise, miniaturization and long life. In order to realize the miniaturization of gear devices and improve the carrying capacity of existing involute gears, hard tooth surface technology is widely used in various countries. During the hobbing process of gears with hard tooth surface, the hobbing force and cutting heat are large, the chips are not easy to discharge, the hob wears seriously, and the service life of the hob is low. Moreover, due to the increased hardness of the material, the quenched gear cannot be processed by precision hobbing, so as to further improve the machining accuracy of the gear. However, ultrasonic vibration processing can greatly reduce cutting force and cutting heat, improve cutting cooling and lubrication effects, prolong tool life, and improve surface quality and wear resistance of processed workpieces.

The proposal of ultrasonic precision machining technology for gears relies on the mutual penetration of cutting-edge technologies between ultrasonic vibration theory and advanced manufacturing technology disciplines; mature products of high-power ultrasonic generators and transducers are put on the market, providing material guarantee for the realization of gear ultrasonic precision machining . In order to solve the above problems, Yin Shaohui proposed a schematic device for ultrasonic vibration hobbing experiment in 1995, and completed the ultrasonic hobbing test of a cylindrical gear with a modulus of 1mm and a number of teeth of 24 (see "Ultrasonic vibration hobbing experiment", New Technology and New Technology, 1995 (6): 22.); Luo Kaihua proposed a schematic device for ultrasonic hobbing in 2001, and completed the ultrasonic vibration hobbing experiment of a cylindrical gear with a modulus of 4.5 mm and a number of teeth of 34, ( See "Experimental Research on Ultrasonic Vibration Gear Hobbing", New Technology and New Technology, 2001 (9): 14-15.). However, there is no disclosure of the necessary components of the ultrasonic vibration hobbing experimental device, the ultrasonic power supply reversing system, the gear workpiece rotation system, the external support fixing system, and the connection and installation scheme between the ultrasonic vibration hobbing processing device and the hobbing machine workbench. And it is only suitable for ultrasonic hobbing of short and thick cylindrical gears (gear indexing circle diameter is less than 1/4 longitudinal wavelength in its medium), but there is no report for ultrasonic hobbing devices of cylindrical gears with other shape characteristics.

Contents of the invention

The invention combines the gear ultrasonic vibration with the precision gear hobbing technology, and designs a set of ultrasonic precision gear hobbing device and application suitable for involute cylindrical gears after rough hobbing.

The technical scheme that the present invention takes is:

An ultrasonic precision hobbing device for gears, wherein: it consists of three parts: a gear workpiece rotation and ultrasonic vibration composite spindle system, an external support fixing system, and an ultrasonic power supply reversing system. The gear workpiece rotation and ultrasonic vibration composite spindle system includes a gear The workpiece rotary spindle, cylindrical transducer, vibration transmission mandrel, luffing mandrel and gear workpiece, in the middle of the outer surface of the gear workpiece rotary spindle, there are bearing positioning steps from top to bottom, and two rubber insulating sleeve installation grooves , there are four heat dissipation holes in the middle and lower part of the rotary spindle of the gear workpiece, a groove is provided in the middle of the top of the vibration transmission mandrel, a clamping plane is provided on the middle and upper part of the outer surface of the vibration transmission mandrel, and the vibration transmission mandrel The middle and upper part of the outer surface is located below the clamping plane, and a flange is provided, and an axial positioning boss is provided under the flange, a center hole is provided in the middle of the top of the luffing mandrel, and a On the clamping plane, a guiding and positioning boss is provided at the middle and lower part of the luffing mandrel; the vibration-transmitting mandrel is inserted into the inside of the gear workpiece rotary spindle and the flange is fixed on the top of the gear workpiece rotary spindle through a screw fixing assembly, and the screw fixing assembly is along the circumference Installed evenly every 60°, the cylindrical transducer is located at the same height as the heat dissipation hole in the rotary spindle of the gear workpiece, and is connected to the lower end of the vibration transmission mandrel through a precision fine thread, and the upper end of the vibration transmission mandrel is passed through a precision fine thread The thread is connected with the lower end of the luffing mandrel, and ensures that the guiding and positioning boss fits closely with the groove, and the upper end of the luffing mandrel is connected with the gear workpiece through a nut fixing assembly;

The outer support fixing system includes an outer support fixing frame, an ultra-precision high-speed angular contact ball bearing, a felt ring oil seal and a flange end cover. The inner ring of the ultra-precision high-speed angular contact ball bearing is installed on the bearing positioning step of the rotary spindle of the gear workpiece Above, the outer ring of the ultra-precision high-speed angular contact ball bearing is installed on the inner cylindrical positioning step of the outer support fixed frame, the flange end cover is fixed on the upper end surface of the outer support fixed frame by screws, and the felt ring oil seal is installed on the flange end cover Between the rotary spindle of the gear workpiece;

The ultrasonic power supply commutation system includes an ultrasonic generator, two conductive copper rings, two graphite brushes, two rubber insulating sleeves and insulated wires, the ultrasonic generator is placed on the upper surface of the outer support fixture, and two rubber insulating The sleeves are respectively installed in the two rubber insulating sleeve installation grooves of the gear workpiece rotary spindle, the two conductive copper rings are respectively installed in the annular grooves of the two rubber insulating sleeves, and the two graphite brushes pass through the outer support fixing frame and the graphite The contact inner cylindrical surface of the brush maintains strong and uniform contact with the outer cylindrical surface of the conductive copper ring; the power line of the ultrasonic generator is connected to the outer end of the graphite brush, one end of the insulated wire is connected to the conductive copper ring, and the other end of the insulated wire is connected to the The terminals of the cylindrical transducer are connected.

Wherein the gear workpiece can be a thin disc gear workpiece, a medium thick disc gear workpiece or a short thick cylindrical gear workpiece.

The application of the gear ultrasonic precision gear hobbing device of the present invention, wherein: the shaft end flange at the bottom of the rotary spindle of the gear workpiece is installed in the T-shaped groove of the rotary disc on the gear hobbing machine worktable through the bolt nut gasket fixing assembly, and the bolt nut gasket The sheet fixing components are installed evenly every 120° along the circumference, and the outer support fixing frame is fixed in the T-shaped groove of the gear hobbing machine workbench through the bolt nut washer fixing components, and the sliding support frame is controlled on the small column by inputting instructions into the gear hobbing machine control panel. Slide on the slide rail so that the top of the sliding support frame is in the center hole of the upper end surface of the luffing mandrel, and the connecting beam connects the column with the small column, and then the gear hob turret is controlled by inputting instructions into the control panel. Move on the column slide rail to adjust the position of the gear hob to achieve alignment with the gear workpiece; adjust the gear hobbing machine through the indexing worm pair on the bed so that the speed ratio of the gear hob and the gear workpiece is equal to the ratio of the number of teeth of the gear workpiece to the number of gear hob heads Ratio; the column is driven by the slide rail on the bed to realize the radial feed movement, and the gear hob turret is driven by the column slide rail on the column to realize the axial feed movement; the meshing cutting motion of the gear hob and the gear workpiece conforms to the helical gear According to the meshing principle, the two complete the meshing and cutting motion of the cross-axis involute cylindrical gear, and realize the ultrasonic precision hobbing of the gear.

According to the present invention, the thin disc gear workpiece, the medium-thick disc gear workpiece or the short and thick cylindrical gear workpiece ultrasonic vibration mode and the specific feeding method of the gear hob are as follows: during the ultrasonic precision hobbing of the thin disc gear workpiece, the gear workpiece is Radial ultrasonic vibration at a frequency of 20kHz is performed while the indexing rotation is completed, and the gear hob is fed radially; when the ultrasonic precision hobbing of the medium-thick disc gear workpiece is performed, the gear workpiece is subjected to a 20kHz frequency pitch while the indexing rotation is completed. Circular transverse bending ultrasonic vibration, gear hob radial-axial combined feed; during ultrasonic precision hobbing of short and thick cylindrical gear workpieces, the gear workpiece undergoes longitudinal ultrasonic vibration at a frequency of 20kHz while completing the indexing rotation, and the gear hobbing The knife axially feeds in segments.

The invention combines the ultrasonic vibration of the gear with the hobbing process of the hard tooth surface gear, and is suitable for the ultrasonic precision hobbing of the involute cylindrical gear after rough hobbing. It can prolong the service life of the hob, improve the roughness of the tooth surface, improve the machining accuracy of the gear hobbing, improve the microscopic cutting texture of the tooth surface, and achieve the purpose of reducing noise and improving wear resistance.

Description of drawings

Fig. 1 is the perspective view of the gear ultrasonic precision gear hobbing device of the present invention;

Fig. 2 is a cross-sectional view of the gear ultrasonic precision hobbing device of the present invention;

Fig. 3 is a partial enlarged view of place A in Fig. 2;

Fig. 4 is a schematic structural view of the rotary spindle of the gear workpiece of the present invention;

Fig. 5 is a schematic structural view of the vibration-transmitting mandrel of the present invention;

Fig. 6 is a schematic structural view of the luffing mandrel of the present invention;

Fig. 7 is the structural representation of flange end cover of the present invention;

Fig. 8 is a perspective view of the outer support fixture of the present invention;

Fig. 9 is a sectional view of Fig. 8;

Fig. 10 is the structural representation of graphite electric brush of the present invention;

Fig. 11 is a schematic structural view of a rubber insulating sleeve of the present invention;

Fig. 12 is a schematic structural view of the ultrasonic precision gear hobbing machine of the present invention;

Fig. 13 is a schematic diagram of the position structure of the ultrasonic precision gear hobbing device of the present invention on the gear hobbing machine;

Fig. 14 is a schematic diagram of the combined movement direction of the stubby cylindrical gear workpiece and the hob in the present invention;

Fig. 15 is a schematic diagram of the combined movement direction of the thin disc cylindrical gear workpiece and the hob according to the present invention;

Fig. 16 is a schematic diagram of the combined movement direction of the medium-thick disc cylindrical gear workpiece and the hob according to the present invention.

detailed description

Example 1

As shown in Fig. 1, Fig. 2, Fig. 3, Fig. 4, Fig. 5, Fig. 6, Fig. 7, Fig. 8, Fig. 9, Fig. 10 and Fig. 11, an ultrasonic precision hobbing device for gears consists of a gear workpiece rotating and The ultrasonic vibration composite spindle system consists of three parts: an external support fixing system and an ultrasonic power supply reversing system. The gear workpiece rotation and ultrasonic vibration composite spindle system includes a gear workpiece rotary spindle 1, a cylindrical transducer 2, and a vibration transmission mandrel. 3. The luffing mandrel 5 and the short and thick cylindrical gear workpiece 6 are provided with a bearing positioning step 101 in the middle of the outer surface of the gear workpiece rotary spindle 1 from top to bottom, and two rubber insulating sleeve installation grooves 102. The middle and lower part of the main shaft 1 is provided with four heat dissipation holes 103, and the four heat dissipation holes 103 are evenly distributed along the circumferential direction, and a groove 301 is arranged in the middle of the top of the vibration transmission mandrel 3, and the groove 301 is between the vibration transmission mandrel 3 and the transformer. When the amplitude mandrel 5 is assembled and connected, it plays a role of guiding and positioning. A clamping plane 302 is provided on the middle and upper part of the outer surface of the vibration transmitting mandrel 3. The clamping plane 302 is used for assembling and connecting the amplitude mandrel 5 and the vibration transmitting mandrel 3 Clamped by a fashion clip, a flange 303 is provided on the middle and upper part of the outer surface of the vibration-transmitting mandrel 3 below the clamping plane 302. The flange 303 is the longitudinal vibration displacement of the vibration node when the vibration-transmitting mandrel 3 resonates close to zero. It is used for the installation, connection and fastening of the vibration transmission mandrel 3 and the gear workpiece rotary spindle 1. A circumferential positioning boss 304 is provided under the flange 303, and the circumferential positioning boss 304 is used for the vibration transmission mandrel 3 and the gear. Circumferential positioning when the workpiece rotary spindle 1 is installed, connected and tightened, a center hole 501 is provided in the middle of the top of the luffing mandrel 5, and the tail tip of the support frame 30 is in the center hole 501 during ultrasonic precision hobbing during use, reducing For the rotation of the gear workpiece during processing and the deformation of the ultrasonic vibration composite spindle system, a clamping plane 502 is provided in the middle of the luffing mandrel 5, and the clamping plane 502 is used for mounting the luffing mandrel 5 and the vibration transmission mandrel 3. For clamping and clamping use, a guiding and positioning boss 503 is provided at the middle and lower part of the luffing mandrel 5, and the guiding and positioning boss 503 ensures the coaxiality requirements of the luffing mandrel 5 and the vibration transmission mandrel 3 after matching; the vibration transmission core Shaft 3 is inserted into the inside of the gear workpiece rotary spindle 1 and the flange 303 is fixed on the top of the gear workpiece rotary spindle 1 through the screw fixing assembly 4. The screw fixing assembly 4 is installed evenly every 60° along the circumference, and the cylindrical transducer 2 is located on the gear The workpiece rotary spindle 1 is at the same height as the cooling hole 103 and is connected to the lower end of the vibration transmission mandrel 3 through a precision fine thread, and the upper end of the vibration transmission mandrel 3 is connected to the lower end of the luffing mandrel 5 through a precision fine thread , and ensure that the guiding and positioning boss 503 is closely matched with the groove 301, so that the radial runout error of the luffing mandrel 5 is controlled within 0.005 mm, and the runout error of the end surface is controlled within 0.003 mm. The upper end of the luffing mandrel 5 passes through The nut fixing assembly 7 is connected with the gear workpiece 6;

The outer support fixing system includes an outer support fixing frame 16, an ultra-precision high-speed angular contact ball bearing 11, a felt ring oil seal 8 and a flange end cover 9, and the inner ring of the ultra-precision high-speed angular contact ball bearing 11 is installed on the rotating gear workpiece. On the bearing positioning step 101 of the main shaft 1, the outer ring of the ultra-precision high-speed angular contact ball bearing 11 is installed on the inner cylindrical surface positioning step of the outer support fixed frame 16, and the flange end cover 9 is fixed on the outer support fixed frame 16 by screws 10 On the end face, the felt ring oil seal 8 is installed between the flange end cover 9 and the rotary spindle 1 of the gear workpiece;

Described ultrasonic power commutation system comprises supersonic generator 17, two conductive copper rings 12, graphite electric brush 13, two rubber insulating sleeves 14 and insulated wire 15, and supersonic generator 17 is placed on the upper surface of outer supporting fixture 16 , two rubber insulating sleeves 14 are respectively installed in the two rubber insulating sleeve installation grooves 102 of the gear workpiece rotary spindle 1, two conductive copper rings 12 are respectively installed in the annular grooves of the two rubber insulating sleeves 14, and the two graphite electrical The brushes 13 respectively pass through the outer supporting fixture 16 and the contact arc surface of the graphite brush 13 is in strong and even contact with the cylindrical surface of the conductive copper ring 12, so as to complete the electric energy transmission between the ultrasonic generator 17 and the cylindrical transducer 2, and the electric energy The transmission route is successively: ultrasonic generator 17, graphite electric brush 13, conductive copper ring 12, insulated wire 15 and cylindrical transducer 2; the power line of ultrasonic generator 17 is connected with the outer end of graphite electric brush 13, and insulated wire 15 one ends link to each other with conductive copper ring 12, and the other end of insulated wire 15 links to each other with the binding post of cylindrical transducer 2, for preventing the twisting of ultrasonic generator 17 power cords, gear workpiece 6, gear workpiece rotary main shaft 1, column The shape transducer 2, the vibration-transmitting mandrel 3, and the luffing mandrel 5 rotate together at the same angular speed, and the outer support and fixation frame 16 is used to ensure that the outer support and fixation frame 16 and the graphite brush 13 are stationary relative to the gear hobbing machine workbench 19.

During ultrasonic precision hobbing, start the power switch of the ultrasonic generator 17, and the cylindrical transducer 2 converts the obtained ultrasonic signal into an ultrasonic mechanical vibration of about 10 μm through the internal hysteresis material, and then transmits it to the vibration transmission mandrel 3 After the ultrasonic mechanical vibration is concentrated and amplified by the luffing mandrel 5, it is transmitted to the tooth surface of the gear workpiece 6. While the gear workpiece is indexed and rotated, the ultrasonic mechanical vibration is also performed, and then the gear hob 25 is meshed and cut, The combination of feed motion completes the ultrasonic precision hobbing of gears.

The application of the gear ultrasonic precision gear hobbing device in this embodiment is as follows: as shown in Figure 12 and Figure 13, the shaft end flange 104 at the bottom of the gear workpiece rotary spindle 1 is installed on the gear hobbing machine workbench 19 through the bolt, nut and washer fixing components. In the T-shaped groove of the rotary disc 20, bolts, nuts, and gaskets are fixedly installed along the circumference every 120°, and the outer support frame 16 is fixed in the T-shaped groove of the gear hobbing machine table 19 through the bolts, nuts, and gaskets. Input commands to the gear hobbing machine control panel 21 to control the sliding support frame 30 to slide on the small column slide rail 28, so that the top of the sliding support frame 30 is in the center hole 501 of the upper end surface of the luffing mandrel 5, and the connecting beam 27 connects the column 22 is connected with the small column 29 to ensure the rigidity of the system in the ultrasonic precision hobbing process, and then by inputting instructions into the control panel 21, the gear hob turret 23 is controlled to move on the column slide rail 26 to adjust the gear hob 25 Position, to achieve alignment with the gear workpiece 6; adjust the hobbing machine through the indexing worm pair 32 on the bed 18 so that the speed ratio of the gear hob 25 and the gear workpiece 6 is equal to the ratio of the number of teeth of the gear workpiece 6 to the number of gear hobs 25 heads; The slide rail 31 on the bed 18 drives the column 22 to realize the radial feed motion, and the gear hob turret 23 is driven by the column slide rail 26 on the column 22 to realize the axial feed motion; the gear hob 25 and the gear workpiece 6 The meshing cutting motion conforms to the meshing principle of the helical gear, and the two complete the meshing cutting motion of the interlaced involute cylindrical gear to realize the ultrasonic precision hobbing of the gear. To achieve the purpose of prolonging the service life of the hob, improving the roughness of the tooth surface, improving the machining accuracy of the gear hobbing, improving the microscopic cutting texture of the tooth surface, reducing noise and improving wear resistance.

The gear workpiece 6 in this embodiment may be a thin disc gear workpiece, a medium-thick disc gear workpiece or a short and thick cylindrical gear workpiece.

The ultrasonic vibration mode of the thin disc gear workpiece 6 and the specific feeding method of the gear hob 25 are as follows: see Figure 14, when the thin disc gear workpiece 6 is ultrasonically precision hobbed, the gear workpiece 6 is rotated while completing the index rotation. 20kHz radial ultrasonic vibration, gear hob 25 radial feed;

The ultrasonic vibration mode of the medium-thick disc gear workpiece 6 and the specific feeding method of the gear hob 25 are as follows: See Figure 15. During the ultrasonic precision hobbing of the medium-thick disc gear workpiece 6, the gear workpiece 6 is rotated while completing the index rotation. 20kHz pitch circle transverse bending ultrasonic vibration, gear hob 25 radial-axial combined feed;

The ultrasonic vibration mode of the short and thick cylindrical gear workpiece 6 and the specific feeding method of the gear hob 25 are as follows: see Figure 16. During the ultrasonic precision hobbing of the short and thick cylindrical gear workpiece 6, the gear workpiece 6 performs a 20 kHz frequency while completing the indexing rotation. Longitudinal ultrasonic vibration, the gear hob 25 is axially fed in segments.

Claims (4)

1. A gear ultrasonic precision hobbing device is characterized in that: it is composed of three parts: the rotation of the gear workpiece and the composite spindle system of ultrasonic vibration, the external support fixing system and the reversing system of the ultrasonic power supply, and the rotation of the gear workpiece and the composite of ultrasonic vibration The spindle system includes a gear workpiece rotary spindle (1), a cylindrical transducer (2), a vibration transmission spindle (3), an amplitude spindle (5) and a gear workpiece (6). The gear workpiece rotary spindle (1) The middle part of the outer surface is provided with bearing positioning steps (101), two rubber insulating sleeve installation grooves (102) from top to bottom, and four cooling holes (103) are opened in the middle and lower part of the gear workpiece rotary spindle (1). A groove (301) is provided in the middle of the top of the vibration-transmitting mandrel (3), and a clamping plane (302) is provided on the middle and upper part of the outer surface of the vibration-transmitting mandrel (3). The middle and upper part of the surface is located below the clamping plane (302), and a flange (303) is provided, and an axial positioning boss (304) is provided below the flange (303), and the center of the top of the luffing mandrel (5) A central hole (501) is provided, a clamping plane (502) is provided in the middle of the luffing mandrel (5), and a guiding and positioning boss (503) is provided at the middle and lower part of the luffing mandrel (5); The mandrel (3) is inserted into the inside of the gear workpiece rotary spindle (1) and the flange (303) is fixed on the top of the gear workpiece rotary spindle (1) through the screw fixing assembly (4). The cylindrical transducer (2) is located at the same height as the heat dissipation hole (103) in the gear workpiece rotary spindle (1) and is connected to the lower end of the vibration-transmitting mandrel (3) through precision fine-tooth threads. The upper end of the vibrating mandrel (3) is connected to the lower end of the luffing mandrel (5) through a precision fine thread, and the guiding positioning boss (503) is closely matched with the groove (301), and the luffing mandrel (5 ) is connected with the gear workpiece (6) through the nut fixing assembly (7); The outer support fixing system includes an outer support fixing frame (16), an ultra-precision high-speed angular contact ball bearing (11), a felt ring oil seal (8) and a flange end cover (9), an ultra-precision high-speed angular contact ball bearing ( The inner ring of 11) is installed on the bearing positioning step (101) of the gear workpiece rotary spindle (1), and the outer ring of the ultra-precision high-speed angular contact ball bearing (11) is installed on the inner cylindrical surface positioning step of the outer support fixture (16) , the flange end cover (9) is fixed on the upper end surface of the outer support bracket (16) by screws (10), and the felt ring oil seal (8) is installed on the flange end cover (9) and the gear workpiece rotary spindle (1) between; The ultrasonic power commutation system includes an ultrasonic generator (17), two conductive copper rings (12), two graphite brushes (13), two rubber insulating sleeves (14) and insulated wires (15), ultrasonic The generator (17) is placed on the upper surface of the outer support bracket (16), and the two rubber insulating sleeves (14) are respectively installed in the two rubber insulating sleeve installation grooves (102) of the gear workpiece rotary spindle (1). The conductive copper rings (12) are respectively installed in the annular grooves of the two rubber insulating sleeves (14), and the two graphite brushes (13) respectively pass through the outer support bracket (16) and the graphite brushes (13) are in contact with each other. The cylindrical surface maintains strong and uniform contact with the outer cylindrical surface of the conductive copper ring (12); the power line of the ultrasonic generator (17) is connected to the outer end of the graphite brush (13), and one end of the insulated wire (15) is connected to the conductive copper ring ( 12), and the other end of the insulated wire (15) is connected to the terminal of the cylindrical transducer (2). 2. The ultrasonic precision gear hobbing device according to claim 1, characterized in that: the gear workpiece (6) can be a thin disc gear workpiece, a medium-thick disc gear workpiece or a short and thick cylindrical gear workpiece. 3. The application of the gear ultrasonic precision gear hobbing device according to claim 1, characterized in that: the shaft end flange (104) at the bottom of the gear workpiece rotary spindle (1) is installed on the gear hobbing machine workbench ( 19) In the T-shaped groove of the rotary disc (20) on the top, bolts, nuts, and gaskets are fixedly installed along the circumference every 120°, and the outer support frame (16) is fixed on the gear hobbing machine workbench through the bolts, nuts, and gaskets. In the T-shaped slot of (19), the sliding support frame (30) is controlled to slide on the small column slide rail (29) by inputting instructions into the gear hobbing machine control panel (21), so that the top of the support frame (30) is changing In the central hole (501) of the upper end face of the mandrel shaft (5), the connecting beam (27) connects the column (22) and the small column (29), and then controls the gear roll by inputting instructions into the control panel (21). The knife turret (23) moves on the column slide rail (26) to adjust the position of the gear hob (25) to achieve alignment with the gear workpiece (6); through the indexing worm pair (32) on the bed (18) ) adjust the gear hobbing machine so that the speed ratio of the gear hob (25) and the gear workpiece (6) is equal to the ratio of the number of teeth of the gear workpiece (6) to the number of gear hobs (25); through the slide rail (31) on the bed (18) Drive the column (22) to realize the radial feed movement of the feed, and drive the gear hob turret (23) to realize the axial feed movement through the column slide rail (26) on the column (22); the gear hob (25 ) and the gear workpiece (6) conform to the principle of helical gear meshing, and the two complete the meshing and cutting motion of the interlaced involute cylindrical gear, realizing the ultrasonic precision hobbing of gears. 4. The application of the ultrasonic precision hobbing device for gears according to claim 3, characterized in that: the gear workpiece (6) can be a thin disc gear workpiece, a medium-thick disc gear workpiece or a short and thick cylindrical gear workpiece, The specific feeding method of the thin disc gear workpiece, medium-thick disc gear workpiece or short and thick cylindrical gear workpiece (6) ultrasonic vibration mode and gear hob (25) is as follows: thin disc gear workpiece (6) ultrasonic precision hobbing During gear machining, the gear workpiece (6) performs radial ultrasonic vibration at a frequency of 20kHz while completing the indexing rotation, and the gear hob (25) feeds radially; the medium-thick disc gear workpiece (6) is processed by ultrasonic precision gear hobbing At the same time, the gear workpiece (6) performs pitch-circle transverse bending ultrasonic vibration at a frequency of 20kHz while completing the indexing rotation, and the gear hob (25) is fed radially and axially; the short and thick cylindrical gear workpiece (6) is ultrasonically During precision hobbing, the gear workpiece (6) undergoes longitudinal ultrasonic vibration at a frequency of 20 kHz while completing the indexing rotation, and the gear hob (25) is axially fed in segments.