An aviation edge milling vibration suppressor with a variable stiffness flexible joint

Abstract

The present invention provides an aviation edge milling vibration suppressor with a variable stiffness flexible joint, which relates to the technical field of part processing equipment. Specifically, the present invention includes an integral base, an installation clamping mechanism, a sliding pressure mechanism, a variable stiffness flexible mechanism, a driving torque mechanism, and a vibration suppression mechanism; the variable stiffness flexible device includes a rotating upper end cover and a spring built into the upper end cover, the sliding pressure mechanism includes a universal ball and a roller, and the universal ball presses the thin-walled part against the roller due to the variable stiffness flexible device. The installation clamping device includes a spindle seat for fixing the electric spindle and a spiral groove for fixing the overall housing of the suppressor. The fixture for suppressing vibration during the milling of aviation thin-walled parts according to the present invention can adapt to the curved surface processing of thin-walled parts, has the advantages of simple operation, low cost, high efficiency, strong practicability, etc., can suppress the deformation of thin-walled parts during milling, and absorb the vibration generated during the processing, providing convenience for the milling of thin-walled parts.

Description

Technical Field

[0001] The present invention relates to the technical field of part processing equipment, and particularly relates to an aviation edge milling vibration suppressor with a variable stiffness flexible joint. Background Art

[0002] With the development of modern industry, thin-walled parts are increasingly widely used in many fields such as aerospace, automotive, and energy. The requirements for the processing quality and efficiency of thin-walled parts are also getting higher and higher. Due to the low stiffness of thin-walled parts, strong forced vibrations or even chatter will occur during the processing. This will seriously affect the surface processing quality of the workpiece and limit the material removal efficiency. During the process of milling laminated thin-walled parts, riveting or screwing is often used for fixation and they are arranged according to a certain positional relationship. Due to the weak stiffness of thin-walled parts, chatter is extremely likely to occur during the milling process. When machining under the condition of the collision between the tool and the workpiece, the thin-walled parts are prone to bending deformation under force, which causes the actual milling width to change and has a certain impact on the machining quality of the workpiece. Summary of the Invention

[0003] Aiming at the deficiencies of the prior art, the present invention provides an aviation edge milling vibration suppressor with a variable stiffness flexible joint. The present invention is a flexible fixture with variable stiffness, which has the advantages of simple operation, low cost, high efficiency, strong practicability, etc. It can suppress the deformation during the milling of thin-walled parts and absorb the vibrations generated during the processing, providing convenience for the milling of thin-walled parts.

[0004] An aviation edge milling vibration suppressor with a variable stiffness flexible joint specifically includes an overall base, an installation and clamping mechanism, a sliding pressure mechanism, a variable stiffness flexible mechanism, a driving torque mechanism, and a vibration suppression mechanism;

[0005] The installation and clamping mechanism is fixed on the end flange of the robot by the base, and the housing of the variable stiffness flexible mechanism is fixed on the overall base through a rotating groove;

[0006] The variable stiffness flexible mechanism consists of a lower base, an upper end cover, and a housing. The upper end cover is placed inside the housing. Both ends of the spring are respectively fixed to the upper end cover and the lower base of the variable stiffness flexible mechanism through spring bases. A guide post is arranged at the center of the upper end cover, and a linear bearing is fixedly arranged at the center of the lower base. The linear bearing is connected with the lower base by interference fit. The upper end cover realizes guiding and connection through the guide post and the linear bearing, and cylindrical rollers are arranged on the outer surface of the upper end cover;

[0007] The sliding pressure mechanism consists of a universal ball, a roller, and a bearing lower arm. The universal ball is screwed to the lower base of the variable stiffness flexible mechanism by screws, and the inner diameter of the roller is in interference fit with the bearing lower arm;

[0008] The driving torque mechanism consists of a servo motor, a harmonic reducer, a thrust bearing, and a rotating cam groove. The servo motor is fixed to the overall base through a motor base. One end of the harmonic reducer is connected to the servo motor, and the other end is connected to the rotating cam groove through a coupling. The rotating cam groove is connected to the cylindrical roller on the outer surface of the upper end cover through the cam groove. The thrust bearing is placed inside the upper surface of the housing, and the rotating cam groove is connected to the housing through the thrust bearing. The end of the rotating cam groove is connected to the servo motor through a coupling to prevent axial movement of the rotating cam groove.

[0009] The vibration suppression mechanism consists of two eddy current dampers. The two eddy current dampers are installed on the overall base by screwing and are installed on the milling electric spindle through the overall base. The two eddy current dampers are perpendicular to each other.

[0010] The beneficial effects of adopting the above technical solutions are as follows:

[0011] The present invention provides an aviation edge milling vibration suppressor with a variable stiffness flexible joint, having the following beneficial effects:

[0012] 1) The whole of the present invention is integrated on the electric spindle and can move with the movement of the tool during milling.

[0013] 2) The variable stiffness flexible mechanism of the present invention can suppress the deformation of thin-walled parts during the machining process and absorb the vibration generated during milling.

[0014] 3) The moving pair made of the elastic notched universal ball and the roller of the present invention can realize the moving machining of the curved surface of the thin-walled part.

[0015] 4) The present invention has a good clamping effect on the milling of thin-walled parts with a laminated structure.

[0016] 5) The present invention can absorb the vibration generated by the robot during the milling process. Description of the Drawings

[0017] Figure 1 is a schematic structural diagram of the aviation edge milling vibration suppressor provided by the embodiment of the present invention;

[0018] In the figure, 1 - overall base, 3 - bearing arm, 4 - roller, 12 - servo motor, 13 - housing, 14 - eddy current damper;

[0019] Figure 2 is a schematic structural diagram of the variable stiffness flexible mechanism provided by the embodiment of the present invention;

[0020] In the figure, 2 - universal ball, 5 - lower base, 6 - upper end cover, 7 - spring, 9 - rotating cam groove, 10 - thrust bearing, 11 - coupling;

[0021] Figure 3This is a schematic structural diagram of the lower base provided by an embodiment of the present invention;

[0022] In the figure, 8 is a linear bearing. Specific embodiments

[0023] The following combines the accompanying drawings and embodiments to further describe in detail the specific embodiments of the present invention. The following embodiments are used to illustrate the present invention, but are not used to limit the scope of the present invention.

[0024] An aviation edge milling vibration suppressor with a variable stiffness flexible joint, as Figure 1 shown, specifically includes an overall base, an installation clamping mechanism, a sliding pressure mechanism, a variable stiffness flexible mechanism, a driving torque mechanism, and a vibration suppression mechanism;

[0025] The installation clamping mechanism is fixed on the end flange of the robot by the base. The housing of the variable stiffness flexible mechanism is fixed on the overall base through a rotating groove, making the lower end flush with the upper surface of the lower base 5 to prevent chips from splashing into the interior during milling and causing damage to the interior, and keeping the housing 13 and the electric spindle non-interfering with each other;

[0026] The variable stiffness flexible mechanism is as Figure 2 , Figure 3 shown, and is composed of a lower base, an upper end cover, and a housing. The upper end cover is placed inside the housing. Both ends of the spring are respectively fixed to the upper end cover and the lower base of the variable stiffness flexible mechanism through spring bases. A guide post is provided at the center of the upper end cover, and a linear bearing is fixedly provided at the center of the lower base. The linear bearing is connected to the lower base by interference fit. The upper end cover realizes guidance and connection through the guide post and the linear bearing, realizes the functions of guidance and bearing axial force, and cylindrical rollers are arranged on the outer surface of the upper end cover; the maximum lead of the guide post is the length of the linear bearing 8 to prevent the lead from being too large and colliding with the universal ball 2; the linear bearing is fixed at the center of the lower base and keeps a certain distance from the spring 7 so that the spring 7 can be freely compressed. The housing plays a role in preventing chips and protecting all parts;

[0027] The sliding pressure mechanism is composed of a universal ball, a roller, and a load-bearing lower arm. The universal ball can roll with all degrees of freedom and is screwed to the lower base of the variable stiffness flexible mechanism through screws. The inner diameter of the roller is in interference fit with the load-bearing lower arm; the universal ball and the roller clamp the workpiece up and down, and can realize synchronous movement with the electric spindle on the surface of the curved workpiece;

[0028] The driving torque mechanism consists of a servo motor, a harmonic reducer, a thrust bearing, and a rotating cam groove. The servo motor is fixed to the overall base through a motor base. One end of the harmonic reducer is connected to the servo motor, and the other end is connected to the rotating cam groove through a coupling. The rotating cam groove is connected to the cylindrical roller on the outer surface of the upper end cover through the cam groove. The thrust bearing is placed inside the upper surface of the housing to ensure the rotation of the rotating cam groove 9 under the action of the motor. The rotating cam groove is connected to the housing through the thrust bearing, and the end of the rotating cam groove is connected to the servo motor through a coupling to prevent the axial movement of the rotating cam groove.

[0029] The vibration suppression mechanism consists of two eddy current dampers. The two eddy current dampers are installed on the overall base by screwing and are installed on the milling electric spindle through the overall base. The two eddy current dampers are perpendicular to each other to damp the spindle vibration in two radial directions.

[0030] The usage method of the aviation edge milling vibration suppressor in this embodiment is as follows:

[0031] First, fixedly install the overall base 1 on the end of the robot through a flange, and install the tool connected to the electric spindle through the reserved electric spindle slot.

[0032] Secondly, adjust the overall variable stiffness mechanism, feed in the thin-walled part to be processed. The servo motor 12 rotates through the reducer to drive the rotating cam groove 9 through the coupling. The rotating cam groove 9 rotates through the thrust bearing 10 inside the housing 13, and the rotating cam groove 9 drives the upper end cover 6 to achieve downward feeding through the rotation of the cam groove.

[0033] Thirdly, when the upper end cover 6 feeds downward, the cooperation between the guide post and the linear bearing 8 prevents the spring 7 from twisting and realizes the compression of the spring.

[0034] Finally, the variable stiffness is realized through the compression of the spring 7, so that the universal ball 2 connected to the lower base 5 presses on the surface of the thin-walled part to be milled according to the preset pressure. When milling, the universal ball 2 and the roller 4 move on the surface of the thin-walled part as the tool moves. When the tool collides with the workpiece during milling, the generated vibration force will be absorbed by the spring 7 through the universal ball 2 and the lower base 5.

[0035] The above description is only the preferred embodiment of the present disclosure and the explanation of the applied technical principles. Those skilled in the art should understand that the scope of the invention involved in the embodiments of the present disclosure is not limited to the technical solutions formed by the specific combination of the above technical features, and should also cover other technical solutions formed by any combination of the above technical features or their equivalent features without departing from the above inventive concept. For example, the technical solutions formed by mutually replacing the above features with the technical features (but not limited to) disclosed in the embodiments of the present disclosure with similar functions.

Claims

1. An aviation edge milling vibration suppressor with a variable stiffness flexible joint, characterized in that It includes an overall base, an installation clamping mechanism, a sliding pressure mechanism, a variable stiffness flexible mechanism, a driving torque mechanism, and a vibration suppression mechanism; The installation clamping mechanism is fixed on the end flange of the robot by the base; The variable stiffness flexible mechanism consists of a lower base, an upper end cover and a housing. The upper end cover is placed inside the housing. Both ends of the spring are respectively fixed to the upper end cover and the lower base of the variable stiffness flexible mechanism through spring bases. A guide post is arranged at the center of the upper end cover, and a linear bearing is fixedly arranged at the center of the lower base. The linear bearing is connected with the lower base by interference fit. The upper end cover realizes guidance and connection through the guide post and the linear bearing. Cylindrical rollers are arranged on the outer surface of the upper end cover; The sliding pressure mechanism consists of a universal ball, a roller and a bearing lower arm. The universal ball is screwed to the lower base of the variable stiffness flexible mechanism by screws. The inner diameter of the roller is in interference fit with the bearing lower arm; The driving torque mechanism consists of a servo motor, a harmonic reducer, a thrust bearing and a rotating cam groove. The servo motor is fixed to the overall base through a motor seat. One end of the harmonic reducer is connected to the servo motor, and the other end is connected to the rotating cam groove through a coupling. The rotating cam groove is connected to the cylindrical rollers on the outer surface of the upper end cover through the cam groove; The thrust bearing is placed inside the upper surface of the housing, and the rotating cam groove is connected to the housing through the thrust bearing. The end of the rotating cam groove is connected to the servo motor through a coupling; The vibration suppression mechanism consists of two eddy current dampers. The two eddy current dampers are installed on the overall base by screwing and are installed on the milling electric spindle through the overall base.

2. The aviation milling edge vibration suppressor with a variable stiffness flexible joint according to claim 1, characterized in that, The housing of the variable stiffness flexible mechanism is fixed on the overall base through a rotating groove.

3. The aviation milling-edge vibration suppressor with a variable-stiffness flexible joint according to claim 1, wherein, The two eddy current dampers are perpendicular to each other.

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