阅读说明：本技术 一种用于螺旋铣孔的末端执行装置 (End executing device for spiral hole milling ) 是由 刘伟军 焦安源 王静 于 2020-04-30 设计创作，主要内容包括：本发明涉及一种适用于螺旋铣孔的末端执行装置,该装置的伺服电机和螺旋铣单元组件通过离合转换机构组件连接,螺旋铣单元组件上设置有压脚单元组件；本发明中的单个伺服电机同时控制偏心调节和公转。通过控制气缸来控制齿轮的啮合状态,实现调节偏心距与螺旋铣孔状态的切换,最终实现单个伺服电机同时控制偏心调节和公转,同时也降低了装置的自重。(The invention relates to a tail end execution device suitable for spiral hole milling, wherein a servo motor of the device is connected with a spiral milling unit assembly through a clutch conversion mechanism assembly, and a presser foot unit assembly is arranged on the spiral milling unit assembly; the single servo motor in the invention controls the eccentric adjustment and revolution simultaneously. The meshing state of the gear is controlled by the control cylinder, the switching between the eccentric distance adjustment and the spiral hole milling state is realized, finally, the eccentric adjustment and the revolution are simultaneously controlled by a single servo motor, and the dead weight of the device is reduced.)

1. An end effector for helical milling of holes, comprising: a servo motor of the device is connected with a spiral milling unit assembly through a clutch conversion mechanism assembly, and a presser foot unit assembly is arranged on the spiral milling unit assembly;

the spiral milling unit assembly comprises a base (12), an equipment outer shell (15), an inner sleeve (19), an outer sleeve (18) and a water-cooling electric spindle (13), the equipment outer shell (15) is fixed on the base (12), the outer sleeve (18) is arranged inside the outer shell (15), the inner sleeve (19) is arranged inside the outer sleeve (18), the inner sleeve (19) is movably connected with the outer sleeve (18), a driven gear (14) is arranged on the periphery of the end part of the inner sleeve (19), an eccentric distance e1 exists between the central axis of the inner sleeve (19) and the central axis of the outer sleeve (18), the water-cooling electric spindle (13) is fixed in the inner sleeve (19), and the water-cooling electric spindle (13) and the inner sleeve (19) have an eccentric distance;

the clutch conversion mechanism assembly comprises a gear shifting piece (4), a transmission shaft (5), a primary transmission synchronous pulley (6), a sliding gear (7), a cylinder (9) and a secondary transmission synchronous belt (10), wherein the primary transmission synchronous pulley (6) is connected with the secondary transmission synchronous belt (10) through the transmission shaft (5), the transmission shaft (5) is fixed on a base (12), the primary transmission synchronous pulley (6) is in transmission connection with a synchronous belt driving wheel (20) arranged on an output shaft of a servo motor (1), the secondary transmission synchronous belt (10) is in transmission connection with a driving outer sleeve (18), the sliding gear (7) is arranged at the end part of the output shaft of the servo motor (1), the sliding gear (7) can be meshed with or separated from the synchronous belt driving wheel (20), the sliding gear (7) is meshed with an inner sleeve gear (14), one end of the gear shifting piece (4) is in contact connection with the sliding gear (7, the other end of the gear shifting piece (4) is connected with the cylinder (9);

the presser foot unit assembly comprises a chuck (16) and a milling cutter (17), the chuck (16) is fixed on the water-cooling electric spindle (13), and the milling cutter (17) is clamped on the chuck (16).

2. The end effector adapted for helical milling of a hole according to claim 1, wherein: the outer sleeve (18) is movably connected with the outer shell (15) through a preset bearing set, and the inner sleeve (19) is also movably connected with the outer sleeve (18) through the preset bearing set.

3. The end effector adapted for helical milling of a hole according to claim 1, wherein: the vector sum of the eccentricity e1 and the eccentricity e2 is greater than or equal to zero, and the vector sum of the eccentricity e1 and the eccentricity e2 is smaller than the radius of the milling cutter (17).

4. The end effector adapted for helical milling of a hole according to claim 1, wherein: the sliding gear (7) is of a structure that gears at two ends are provided with teeth, a groove is arranged in the middle of the sliding gear, one end of the sliding gear (7) can be meshed with the synchronous belt driving wheel (20), the other end of the sliding gear (7) is meshed with the inner sleeve gear (14), and the groove in the middle of the sliding gear (7) is in contact with the gear shifting piece (4).

5. The end effector adapted for helical milling of a hole according to claim 1, wherein: one end of the transmission shaft (5) is connected with an electromagnetic brake (2).

Technical Field

The invention relates to the field of machining and manufacturing of products, in particular to a tail end executing device for spiral hole milling.

Background

With the rapid development of manufacturing technology, cutting processing is taken as a basic process of the manufacturing technology, and great progress is made, particularly in the aerospace field. In the manufacturing process of aerospace products, a large number of holes are needed to be machined in many parts for later positioning, connection and the like. The traditional hole making process needs to be carried out through the procedures of drilling, reaming, spot facing, deburring and the like, although the technical index requirements of hole making can be met, the defects of low efficiency, unstable hole making quality, high processing cost and the like generally exist, and when the specifications of hole making are more, a cutter needs to be frequently replaced, so that the manufacturing precision and the efficiency are further reduced. For large parts of an airplane, due to the high technical requirement on the hole making quality, the large parts can be generally processed only on a large machine tool, and the processing equipment cost is generally high. In addition, with the advance of the development work of large airliners, a great amount of materials with poor processability, such as large-thickness composite materials, titanium alloy and the like, are used on airplanes, and the difficulty of hole making is increased. The traditional hole making mode is a continuous cutting process, the heat dissipation is poor, the heat generated in the machining process can aggravate the abrasion of the cutter, and the service life of the cutter and the machining precision of holes are further influenced. After the spiral hole milling technology appears, a new solution is provided for the problems of the traditional hole making technology. The spiral hole milling technology overcomes some limitations of the traditional drilling technology, can meet the requirements of discontinuous processing, reduces the temperature rise, and can realize that a cutter processes a series of diameter holes. The spiral hole milling process is not only suitable for hole making of common materials, but also has the remarkable advantages of high efficiency, good hole making quality, low cost and the like for hole making of titanium alloy, aviation composite materials and the like.

Chinese patent CN102689040B discloses a spiral hole milling device, which realizes the function of spiral hole milling of a workpiece by manually adjusting the eccentricity, but the eccentricity cannot be automatically adjusted, manual assistance is required, and the problem of eccentric error exists.

Chinese patent CN108515216B discloses a helical milling device, which realizes a motor-driven revolution mechanism and an eccentric adjustment mechanism, and ensures the precision of the machined holes, but the device needs a plurality of motors as power sources.

Disclosure of Invention

The purpose of the invention is as follows:

the invention provides a tail end execution device for spiral hole milling, which aims to solve the problems and provides a tail end execution device for spiral hole milling, wherein a single motor is used for adjusting spiral holes with different eccentric distances, and the spiral holes with different eccentric distances can be formed.

The technical scheme is as follows:

a servo motor and a spiral milling unit component of the device are connected through a clutch conversion mechanism component, and a presser foot unit component is arranged on the spiral milling unit component;

the spiral milling unit assembly comprises a base, an equipment outer shell, an inner sleeve, an outer sleeve and a water-cooling electric spindle, wherein the equipment outer shell is fixed on the base, the outer sleeve is arranged inside the outer sleeve, the inner sleeve is movably connected with the outer sleeve, a driven gear is arranged on the periphery of the end part of the inner sleeve, an eccentricity e1 exists between the central axis of the inner sleeve and the central axis of the outer sleeve, the water-cooling electric spindle is fixed in the inner sleeve, and the eccentricity e2 exists between the water;

the clutch conversion mechanism component comprises a gear shifting piece, a transmission shaft, a primary transmission synchronous belt wheel, a sliding gear, an air cylinder and a secondary transmission synchronous belt; the primary transmission synchronous belt wheel is connected with the secondary transmission synchronous belt through a transmission shaft, the transmission shaft is fixed on the base, the primary transmission synchronous belt wheel is in transmission connection with a synchronous belt driving wheel arranged on an output shaft of the servo motor, the secondary transmission synchronous belt is in transmission connection with a driving outer sleeve, a sliding gear is arranged at the end part of the output shaft of the servo motor, the sliding gear can be meshed with or separated from the synchronous belt driving wheel, the sliding gear is meshed with an inner sleeve gear, one end of a gear shifting piece is in contact connection with the sliding gear, and the other end of the gear shifting piece is connected;

the presser foot unit component comprises a chuck and a milling cutter, the chuck is fixed on the water-cooling electric spindle, and the milling cutter is clamped on the chuck.

The outer sleeve is movably connected with the outer shell through a preset bearing set, and the inner sleeve is also movably connected with the outer sleeve through the preset bearing set.

The vector sum of the eccentricity e1 and the eccentricity e2 is greater than or equal to zero, and the vector sum of the eccentricity e1 and the eccentricity e2 is smaller than the radius of the milling cutter.

The sliding gear is of a structure that two end gears are provided with teeth, the middle part of the sliding gear is provided with a groove, one end of the sliding gear can be meshed with the synchronous belt driving wheel, the other end of the sliding gear is meshed with the inner sleeve gear, and the groove in the middle of the sliding gear is contacted with the gear shifting piece.

One end of the transmission shaft is connected with an electromagnetic brake.

The advantages and effects are as follows:

1) the single servo motor in the invention controls the eccentric adjustment and revolution simultaneously. The meshing state of the gear is controlled by the control cylinder, the switching between the eccentric distance adjustment and the spiral hole milling state is realized, finally, the eccentric adjustment and the revolution are simultaneously controlled by a single servo motor, and the dead weight of the device is reduced.

2) The invention has a plurality of holes. The offset of the cutter is adjusted to realize that the cutter with single diameter size can process holes with different diameters, and the deviation compensation is carried out on the holes.

3) The invention improves the service life of the cutter. The spiral milling is an intermittent cutting process, reduces heat accumulation, reduces the abrasion phenomenon of a cutter when a material which is difficult to process is processed, and prolongs the service life of the cutter.

4) The invention reduces the axial force during hole making. By adopting the spiral hole milling process, the axial cutting force is reduced by about 10-20% compared with the traditional drilling method.

5) The invention has multiple functions. The device can be used independently, can also be installed at the tail end of a robot or other numerical control equipment, and can realize spiral hole making with different eccentric distances.

6) The invention improves the hole making quality. The eccentric machining mode ensures that the cuttings have enough discharge space, prevents the cuttings from scratching the surface of the hole wall, is favorable for improving the surface machining quality of the hole wall, and has the hole making precision of H8.

7) The invention has the advantages of compact structure, small volume, energy saving, portability, convenient operation and the like.

Drawings

FIG. 1 is a perspective view of an end effector for helical milling of holes;

FIG. 2 is a schematic view of a screw mechanism of a screw hole milling end effector;

FIG. 3 is a schematic diagram of the eccentric principle of a screw mechanism of the screw hole milling end actuator;

FIG. 4 is a view of a clutch switching mechanism assembly of the spiral milling hole end actuator;

numbering in the figures: 1. a servo motor; 2. an electromagnetic brake; 3. a primary transmission synchronous belt; 4. a gear toggle piece; 5. a drive shaft; 6. a primary transmission synchronous belt wheel; 7. a sliding gear; 8. a pull rod; 9. a cylinder; 10. a secondary transmission synchronous belt; 11. a synchronous pulley; 12. a base; 13. water-cooling the motorized spindle; 14. a driven gear; 15. equipping a shell; 16. a chuck; 17. milling cutters; 18. an outer sleeve; 19. an inner sleeve; 20. a synchronous belt driving wheel; 21. and (7) fixing the plate.

Detailed Description

The function of the end effector for helical milling is further described below with reference to the drawings and the specific examples.

As shown in fig. 1-4, an end effector for helical milling holes comprises a helical milling unit assembly, a presser foot unit assembly, a clutch switching mechanism assembly and a servo motor; the servo motor is connected with the helical milling unit assembly through a clutch switching mechanism assembly, and the helical milling unit assembly is provided with a presser foot unit assembly;

the helical milling unit assembly comprises a base 12, an equipment shell 15, an inner sleeve 19, an outer sleeve 18 and a water-cooling electric spindle 13, wherein the equipment shell 15 is fixed on the base 12, the outer sleeve 18 is arranged inside the shell 15, the outer sleeve 18 is movably connected with the shell 15, the outer sleeve 18 can independently rotate, the inner sleeve 19 is arranged inside the outer sleeve 18, the inner sleeve 19 is movably connected with the outer sleeve 18, a driven gear 14 is arranged on the periphery of the end part of the inner sleeve 19, an eccentric distance e1 exists between the central axis of the inner sleeve 19 and the central axis of the outer sleeve 18, the water-cooling electric spindle 13 is fixed in the inner sleeve 19, and an eccentric distance e2 also exists between; by adjusting the eccentricity e1 and e2, holes with different diameters can be machined by a cutter with a single diameter size, the vector sum of the eccentricity e1 and e2 compensates the hole-making diameter, and finally the hole-making diameter is determined. The eccentric machining mode ensures that the cuttings have enough discharge space, prevents the cuttings from scratching the surface of the hole wall, and is beneficial to improving the surface machining quality of the hole wall.

FIG. 2 is a schematic view of the screw milling bore end effector screw mechanism when the vector sum of the eccentricity e1 and the eccentricity e2 is equal to zero. In this state, the eccentricity is zero, and the hole making function with the same size as the cutter can be realized.

The outer sleeve 18 and the outer shell 15 are movably connected through a preset bearing set, the inner sleeve 19 and the outer sleeve 18 are also movably connected through the preset bearing set, the preset bearing set is a needle bearing, namely a full-filling small needle roller is added between the outer sleeve 18 and the inner sleeve 19, and the full-filling small needle roller is added between the outer sleeve 18 and the equipment outer shell 15, so that the contact rigidity can be improved, and the installation gap can be reduced. The pre-adjusting bearing set is used to reduce the influence of temperature fluctuation under the condition of zero clearance. The maximum diameter of the hole can be made to be 20mm, the hole making precision is H8, and the rotating speed of the main shaft is 40-20000 rpm. The device has the characteristics of compact structure, small volume, energy conservation, portability, convenient operation and the like.

As shown in fig. 1 and 4, the clutch switching mechanism assembly comprises a gear toggle piece 4, a transmission shaft 5, a primary transmission synchronous pulley 6, a sliding gear 7, an air cylinder 9 and a secondary transmission synchronous belt 10; the primary transmission synchronous belt wheel 6 is connected with the secondary transmission synchronous belt 10 through a transmission shaft 5, one end of the transmission shaft 5 is connected with a lower bearing of a base 12 as shown in figure 1, the other end of the transmission shaft 5 penetrates through a fixing plate 22 arranged on the base 12 to be connected with an electromagnetic brake 2, the electromagnetic brake 2 is used for braking the transmission shaft 5, the transmission shaft 5 is in bearing connection with the fixing plate 22, the primary transmission synchronous belt wheel 6 is in transmission connection with a synchronous belt driving wheel 20 arranged on an output shaft of the servo motor 1 through a primary transmission synchronous belt 3, the secondary transmission synchronous belt 10 is in transmission connection with a driving outer sleeve 18 through a secondary transmission synchronous belt wheel 11, namely the secondary transmission synchronous belt 10 can drive the driving; synchronous belt drive wheel 20 and sliding gear 7 have set gradually on servo motor 1's the output shaft, synchronous belt drive wheel 20 can cup joint on the output shaft also can connect on the output shaft through the bearing, servo motor 1's output shaft end is the integral key shaft, gear sliding spline 21 covers on the integral key shaft, sliding gear 7 covers on gear sliding spline 21, make things convenient for sliding gear 7 to make a round trip to slide on the integral key shaft, sliding gear 7 is the longer gear of structure, sliding gear 7 is provided with the tooth for both ends gear, the centre sets up the structure into the recess, sliding gear 7's one end can mesh with synchronous belt drive wheel 20, sliding gear 7's the other end meshes with inner muff gear 14 all the time, the recess in the middle of sliding gear 7 stirs 4. The gear shifting piece 4 is clamped in a groove in the middle of the sliding gear 7, the gear shifting piece 4 is connected with the air cylinder 9 through the pull rod 8, the gear shifting piece 4 is driven by the air cylinder 9 to move the sliding gear 7 along the spline shaft, when the gear shifting piece 4 shifts the sliding gear 7 to move to the right as shown in fig. 4, the sliding gear 7 is separated from the synchronous belt driving wheel 20 at the moment, the sliding gear 7 is only meshed with the inner sleeve gear 14, namely the sliding gear 7 rotates to drive the inner sleeve gear 14 to rotate, and the inner sleeve gear 14 rotates to drive the inner sleeve 19 to rotate; when the gear shifting piece 4 shifts the sliding gear 7 to move to the left as shown in fig. 4, the sliding gear 7 is simultaneously meshed with the synchronous belt driving wheel 20 and the inner sleeve gear 14, so that the switching of the spiral hole milling state is realized, the eccentric adjustment and revolution are simultaneously controlled by a single servo motor, and the self weight of the device is reduced.

Namely, the cylinder 9 drives the gear shifting piece 4 to shift on the gear sliding spline 21, when the gear shifting piece 4 slides the sliding gear 7 to a state of not being meshed with the synchronous belt driving wheel 20, the electromagnetic brake 2 brakes the transmission shaft 5, the transmission shaft 5 brakes equivalently to the primary transmission synchronous belt wheel 6 and the secondary transmission synchronous belt 10, namely, the outer sleeve 18 is also braked; the servo motor 1 only drives the sliding gear 7 to rotate when working, the sliding gear 7 rotates to drive the driven gear 14 to rotate, namely the inner sleeve 19 rotates, and the water-cooled electric spindle 13 and the inner sleeve 19 have an eccentricity e2, namely the eccentricity and revolution of the water-cooled electric spindle 13 can be realized in the state. In this case, holes with different diameters can be machined by the cutter with a single diameter size, and the eccentricity e2 is used for compensating the deviation of the hole diameters.

When the gear shifting piece 4 shifts the sliding gear 7 to a state of being meshed with the synchronous belt driving wheel 20, at the same time, the sliding gear 7 is meshed with the synchronous belt wheel and the driven gear 14 simultaneously, meanwhile, the electromagnetic brake 2 does not brake the transmission shaft 5, the servo motor 1 works to drive the sliding gear 7 to rotate, the sliding gear 7 rotates to drive the synchronous belt driving wheel 20 and the driven gear 14 to rotate simultaneously, the driven gear 14 rotates to drive the inner sleeve 19 to rotate, the synchronous belt driving wheel 20 rotates to drive the primary transmission synchronous belt wheel 6 to rotate through the primary transmission synchronous belt 3, the primary transmission synchronous belt wheel 6 rotates to drive the transmission shaft 5 to rotate, the transmission shaft 5 rotates to drive the secondary transmission synchronous belt 10 to rotate, the secondary transmission synchronous belt 10 rotates to drive the outer sleeve 18 to rotate through the secondary transmission synchronous belt wheel 11, and the, therefore, the inner sleeve 19 and the outer sleeve 18 rotate synchronously, the relative rotation speed of the inner sleeve 19 and the outer sleeve 18 is 0, the inner sleeve 19 realizes eccentric rotation, the relative rotation angle of the inner sleeve 19 and the outer sleeve 18 can be adjusted by setting the motor frequency adjustment of the servo motor 1 in the state that an eccentricity e1 exists between the inner sleeve 19 and the outer sleeve 18 and an eccentricity e2 exists between the inner sleeve 19 and the water-cooled electric spindle 13 (the value is the vector sum of the eccentricity e1 and the eccentricity e 2), and after the eccentricity adjustment is finished, the outer sleeve 18 and the inner sleeve 19 rotate synchronously to drive the water-cooled electric spindle 13 to realize eccentric revolution. In combination with the rotation of the water-cooled motorized spindle 13, the function of processing holes with different diameters by a cutter with a single diameter size can be realized, and the hole making diameter can be compensated by adjusting the eccentricity e 2. And finally, the water-cooling electric spindle 13 drives the presser foot unit assembly to rotate, and the robot drives the spiral hole milling tail end executing device to work, so that the spiral hole milling is realized.

The vector sum of the eccentricity e1 and the eccentricity e2 is equal to or greater than zero, and the vector sum of the eccentricity e1 and the eccentricity e2 is smaller than the radius of the milling cutter 17. The eccentric distance e1=3.5mm in the device; eccentricity e2=3.5 mm. When the vector sum of the eccentricity e1 and the eccentricity e2 is zero, the device can only realize the hole making function with the diameter equal to that of a cutter; when the vector sum of the eccentricity e1 and the eccentricity e2 is not zero, the spiral milling hole making function can be realized.

The presser foot unit assembly comprises a chuck 16 and a milling cutter 17, wherein the chuck 16 is fixed on the water-cooled electric spindle 13, and the milling cutter 17 is clamped on the chuck 16. By replacing the cartridge 16 in order to clamp milling cutters 17 of different diameters.

Selecting a proper milling cutter and an appropriate eccentric distance according to the size requirement of a milling hole, and adjusting the size of the eccentric distance through the rotation quantity motor frequency of the servo motor 1; the servo motor 1 is a power source, and is adjusted by a clutch conversion mechanism assembly, the clutch conversion mechanism assembly controls different meshing states of the sliding gear 7 by controlling the air cylinder 9, so that the switching between the eccentric distance adjustment and the spiral hole milling state is realized, and finally, the eccentric adjustment and revolution control of a single servo motor are realized.

During the operation of the device, firstly, the end executing device is arranged at the end of the robot, and an eccentric value, revolution speed and the rotating speed of the water-cooled electric spindle are input in a control program. Then, the air cylinder 9 in the clutch switching mechanism works to pull the gear toggle piece 4, the sliding gear 7 is toggled to be in a state of not being meshed with the synchronous pulley, the electromagnetic brake 2 works to brake the transmission shaft 5, and the outer sleeve 18 is also braked because the outer sleeve 18 is connected with the transmission shaft 5 through the secondary transmission synchronous belt 10. Then, the revolution and eccentricity adjustment servo motor 1 works to drive the sliding gear 7 to rotate, so as to drive the driven gear 14 and the inner sleeve to rotate, and the eccentricity of the water-cooled electric spindle is realized. Secondly, the air cylinder 9 in the clutch switching mechanism works to push the gear shifting piece 4 to shift the sliding gear 7 to a state of being simultaneously meshed with the synchronous belt wheel and the driven gear 14, the revolution and eccentric adjustment servo motor 1 works to drive the sliding gear 7 to rotate and drive the inner sleeve 19 and the outer sleeve 18 to rotate together, the relative rotating speed of the inner sleeve 19 and the outer sleeve 18 is 0, and therefore the eccentric adjustment and the revolution are simultaneously controlled by a single servo motor. And finally, the water-cooling electric main shaft 13 rotates, and the robot drives the spiral hole milling tail end executing device to work, so that spiral hole milling is realized.