Multi-axis turntable

The present invention relates to the technical field of machine tool, specifically, to a multi-axis turntable.

At present, a common double rotating shaft turntable is generally composed of a swing rotating shaft and a rotating shaft. The two rotating shafts are generally arranged to intersect each other or be offset by a certain distance, and once the design and manufacture are completed, the design and manufacture cannot be changed, as shown in FIG. 1 . The existing turntable is suitable for machining workpieces with the same size as the table top of the workbench, but when machining a smaller workpiece, in order to approach the machining area, it is necessary to use a longer cutting tool, or make the spindle protrude with a longer overhang, resulting in the deterioration of the rigidity of the cutting tool system, a decrease in the surface quality of the workpiece, or even a size over tolerance, and thus, the existing turntable has limitations on the size of the parts to be machined, and is not versatile and flexible enough.

In view of the above problems, a multi-axis turntable is researched and designed in the present invention. The technical solution adopted in the present invention is as follows:

a multi-axis turntable, comprising: a base; a rocker arm; and a first driving device capable of driving the rocker arm to rock around a first rotation axis on the base, wherein a swing arm and a second driving device, which is capable of driving the swing arm to swing around a second rotation axis on the rocker arm, are provided on the rocker arm; a workbench and a third driving device for driving the workbench to rotate around a third rotation axis are provided on the swing arm; and the second rotation axis and the third rotation axis are parallel to each other or on different planes.

Further, the first rotation axis and the second rotation axis intersect each other or are on different planes.

Further, the swinging angle of the swing arm ranges from 0° to 180°. The swinging angle of the swing arm is the angle between the first rotation axis and the line connecting the third rotation axis and the second rotation axis in the workbench plane.

Further, as the swinging angle of the swing arm changes from 0° to 180°, the normal distance from the third rotation axis to the first rotation axis first increases monotonically and then decreases monotonically, or first decreases monotonically and then increases monotonically.

Further, as the swinging angle of the swing arm changes from 0° to 90°, the normal distance from the third rotation axis to the first rotation axis increases monotonically; and as the swinging angle of the swing arm changes from 90° to 180°, the normal distance from the third rotation axis to the first rotation axis decreases monotonically.

Further, the first driving device and the second driving device both include an electric motor and a reducer; and the third driving device is a power mechanism directly driven by a torque motor.

Compared with the prior art, the multi-axis turntable of the present invention has the following advantages.

(1) Compared with the existing double rotating shaft turntable, the multi-axis turntable of the present invention introduces a swingable swing arm, so that the normal distance from the third rotation axis to the first rotation axis is continuously adjustable. Regardless of the size of the workpiece, by adjusting the swinging angle, the workpiece machining area is concentrated near the first rotation axis as much as possible, the overhang of the cutting tool or the overhang of the spindle is basically stable in a small range, and the cutting tool system obtains good and stable rigidity, and thus, the workpiece can obtain consistent and stable surface quality.

(2) Since the workpiece machining area is concentrated near the first rotation axis as much as possible, the machining area is concentrated and the follow compensation movement distance of each shaft is greatly reduced, and thus, the multi-axis turntable has better control characteristics and machining accuracy.

(3) The workpiece is basically offset to one side of the first rotation axis, and the other side can save the space for basic components such as linear shaft, and thus, the interference area is small, the proximity is better, and the good rigidity of the whole machine is easy to obtain.

(4) In the renovation of old equipment, the present invention can be applied to expand the machining range of machine tool and improve the machining accuracy without changing the three-axis stroke.

(5) The multi-axis turntable of the present invention is suitable for but not limited to the machining of impellers and blisks in the aviation field, and can also be applied to gears and propellers, and has wide application prospects in industries such as gas turbines, marine propellers, water pumps, and fans.

FIG. 1 is a schematic structural diagram of a double rotating shaft turntable in the prior art.

FIG. 2 is a schematic structural diagram of an embodiment 1 of the present invention.

FIG. 3 is a schematic view of a workbench plane projection of the embodiment 1 of the present invention.

FIG. 4 is a schematic diagram of a workpiece machining state according to the embodiment 1 of the present invention.

FIG. 5 is a schematic cross-sectional view taken along the line A-A of FIG. 4 .

FIG. 6 is a schematic structural diagram of an embodiment 2 of the present invention.

FIG. 7 is a schematic structural diagram of an embodiment 3 of the present invention.

In the figures: 1 . base, 2 . rocker arm, 3 . first support bearing, 4 . swing arm, 5 . second support bearing, 6 . workbench, 7 . first driving device, 8 . second driving device, 9 . third driving device, 10 . workpiece, 11 . spindle and cutting tool, 1 a . first rotation axis, 2 a . second rotation axis, 3 a . third rotation axis, α. swinging angle, L. normal distance, L 23 . the distance from the projection of the connection between the third rotation axis and the second rotation axis to the workbench plane.

As shown in FIGS. 2 - 5 , a multi-axis turntable includes a base 1 ; a rocker arm 2 ; and a first driving device 7 capable of driving the rocker arm 2 to rock around a first rotation axis 1 a on the base 1 , wherein the rocker arm 2 is arranged on the base 1 via a first support bearing 3 and a second support bearing 5 ; a swing arm 4 and a second driving device 8 , which is capable of driving the swing arm 4 to swing around a second rotation axis 2 a on the rocker arm 2 , are provided on the rocker arm 2 ; a workbench 6 and a third driving device 9 for driving the workbench 6 to rotate around a third rotation axis 3 a are provided on the swing arm 4 ; and the second rotation axis 2 a and the third rotation axis 3 a are parallel to each other or on different planes in a manner that the two are offset by a certain distance, preferably in a manner that the two are parallel to each other.

The first rotation axis 1 a and the second rotation axis 2 a intersect each other or are on different planes, that is, the first rotation axis 1 a and the second rotation axis 2 a intersect each other or there is a certain distance between the two, and preferably, the two are arranged to intersect each other.

The swinging angle α of the swing arm 4 ranges from 0° to 180°. The swinging angle α of the swing arm 4 is the angle between the first rotation axis and the line L 23 connecting the third rotation axis 3 a and the second rotation axis 2 a in the plane of the workbench 6 .

As the swinging angle α of the swing arm 4 changes from 0° to 180°, when the swing arm 4 rotates around the second rotation axis 2 a , the normal distance L of the workbench 6 from the third rotation axis 3 a to the first rotation axis 1 a varies with the swinging angle α in a linear curve according to a function law. The normal distance L from the third rotation axis 3 a to the first rotation axis 1 a is made continuously adjustable. Regardless of the size of the workpiece 10 , by adjusting the swinging angle, the workpiece machining area is made as concentrated as possible near the first rotation axis, and the overhang of the cutting tool 11 or the overhang of the spindle is basically stable in a small range, the cutting tool system has good and stable rigidity, and thus, the workpiece can obtain a surface quality with stable consistency. In a preferred embodiment, the normal distance L from the third rotation axis 3 a to the first rotation axis 1 a first increases monotonically and then decreases monotonically, or first decreases monotonically and then increases monotonically. In a more preferred embodiment, as the swinging angle of the swing arm changes from 0° to 90°, the normal distance L from the third rotation axis 3 a to the first rotation axis 1 a increases monotonically; as the swinging angle of the swing arm changes from 90° to 180°, the normal distance from the third rotation axis to the first rotation axis decreases monotonically. That is to say, when the line L 23 connecting the third rotation axis 3 a and the second rotation axis 2 a in the plane of the workbench 6 is in the third quadrant, the normal distance L from the third rotation axis 3 a to the first rotation axis 1 a increases or decreases monotonically. Accordingly, when in the fourth quadrant, the normal distance L from the third rotation axis 3 a to the first rotation axis 1 a decreases or increases monotonically.

The first driving device 7 and the second driving device 8 both include an electric motor and a reducer, and the third driving device 9 is a power mechanism directly driven by a torque motor. The rocker arm 2 in this embodiment is a rocker arm with support structure at both ends. Both ends of the rocker arm 2 are arranged on the base 1 via the first support bearing 3 , and one end of the two is provided with the first driving device 7 to drive the rocker arm 2 to rock.

Due to the concentrated machining area, the follow compensation movement distance on each axis is greatly reduced in this embodiment, which has better control characteristics. The workpiece is basically offset to one side of the first rotation axis, and the other side can save the space for basic components such as linear shaft, and thus, the interference area is small, the proximity is better, and the good rigidity of the whole machine is easy to obtain. At the same time, in the renovation of old equipment, the present invention can be applied to expand the machining range of machine tool without changing the three-axis stroke. This embodiment is not limited to the machining of impellers and blisks in the aviation field, and can also be applied to gears and propellers, and has wide application prospects in industries such as gas turbines, marine propellers, water pumps, and fans.

As shown in FIG. 6 , the difference between this embodiment and the embodiment 1 is that the two ends of the rocker arm 2 are both provided with the corresponding first driving devices 7 to drive the rocker arm to move from both sides. Other structures of this embodiment are the same as those of the embodiment 1.

As shown in FIG. 7 , the difference between this embodiment and the embodiment 1 is that one end of the rocker arm 2 is arranged on the base 1 via the first support bearing 3 , and the first driving device 7 is arranged at this end of the rocker arm 2 . Other structures of this embodiment are the same as those of the embodiment 1.

The above-mentioned embodiments merely describe the preferred embodiments of the present invention, and do not limit the scope of the present invention. Without departing from the design spirit of the present invention, various modifications and improvements made by a person skilled in the art on the technical solution of the present invention shall fall within the protection scope determined by the claims of the present invention.