Heterogeneous mirror image milling system

Abstract

The invention discloses a heterogeneous mirror image milling system. The heterogeneous mirror image milling system comprises a milling device, a supporting device and a clamping device, the milling device is a three-degree-of-freedom translation parallel mechanism; the supporting device is a series mechanism and comprises a three-degree-of-freedom three-coordinate sliding table and a supporting tail end; the milling device comprises a base which comprises a vertical mounting plate; the fixed platform mechanism comprises a front plate, a rear plate and three supporting legs; the rear plate is fixedly arranged on the front surface of the vertical mounting plate; the rear ends of the supporting legs are fixedly connected with the rear plate; the front ends of the supporting legs are fixedly connected with the front plate; each driving mechanism comprises a sliding groove, a sliding block and a lead screw driven by a motor, and the sliding grooves are laid on the supporting legs; the sliding block is slidably arranged on the sliding groove, and the lead screw is located in the sliding groove. The movable platform mechanism comprises a movable platform and three driving branch chains, each driving branch chain comprises a connecting rod and a spherical hinge, the rear end of each connecting rod is connected with the corresponding sliding block through the spherical hinge, and the front end of each connecting rod is connected with the movable platform through the spherical hinge; and the milling cutter is arranged on the front surface of the movable platform.

Description

Technical Field

[0001] The present invention belongs to the field of mirror milling of thin-walled components, and particularly relates to a heterogeneous mirror milling system. Background Art

[0002] Milling technology is a common metal processing method and one of the key processes widely used in the manufacturing industry. During the milling process, the milling cutter performs rotational and feed motions on the workpiece to achieve material removal. The most direct solution for machining large thin-walled components is to manufacture a large milling machine, and the machine travel should meet the processing requirements. Although large machines have the advantages of a large working space, high rigidity, and high geometric accuracy, they are expensive, have poor reconfigurability, occupy a large area, and cannot perform on-site machining. Mirror milling is a new solution to replace large machines for milling thin-walled components. A milling device with an integrated processing end is used to perform the milling task. At the same time, considering the stress deformation during the machining process of thin-walled components, a support device is used to ensure the local stiffness of the machining position.

[0003] Existing mirror milling processing systems mostly use homogeneous industrial robots to complete collaborative operations. Dalian University of Technology uses a processing system composed of two parallel manipulators (PKMs) to synchronize both sides of a thin-walled component with double-sided features, improving the static stiffness and dynamics of the workpiece, and doubling the productivity. Tianjin University uses a new type of five-axis hybrid manipulator Trimule to develop a dual-robot mirror milling system, and the effectiveness of the system is proven by machining test parts.

[0004] Existing mirror milling processing systems mostly use homogeneous systems, that is, the processing end and the support end adopt the same configuration structure, such as two serial manipulators or two hybrid manipulators. Since the homogeneous system has the same structure on both sides of the workpiece, it is easy to achieve collaborative control and stiffness matching, but there are still many defects. The mirror milling processing system with double serial arms has disadvantages such as poor rigidity, poor accuracy, and weak load-bearing capacity; while the mirror milling processing system with double parallel / hybrid manipulators has advantages such as high rigidity, good dynamic performance, and strong load-bearing capacity, but its working space is limited and its flexibility is poor.

[0005] Therefore, providing a heterogeneous mirror milling system with high rigidity, high precision, and operation flexibility has become a problem that the industry needs to solve. Summary of the Invention

[0006] To solve the deficiencies in the prior art, the main object of the present invention is to provide a heterogeneous mirror milling system, which uses a parallel mechanism with high precision and strong rigidity to complete the milling of the workpiece, and uses a serial mechanism with a larger working space and better flexibility for the support task during the processing.

[0007] To achieve the above main purpose, the present invention discloses a heterogeneous mirror milling system for milling a planar thin-walled member. The heterogeneous mirror milling system includes a milling device, a supporting device, and a clamping device; the clamping device clamps the planar thin-walled member, and the milling device and the supporting device are respectively located on the front and back sides of the planar thin-walled member; the milling device is a three-degree-of-freedom translational parallel mechanism; the supporting device is a serial mechanism, which includes a three-degree-of-freedom three-coordinate slide and a supporting end;

[0008] The milling device includes:

[0009] A base, which includes a vertical mounting plate, and the front side of the vertical mounting plate faces the planar thin-walled member;

[0010] A fixed platform mechanism, which includes a front plate, a rear plate, and three legs; the rear plate is fixedly arranged on the front side of the vertical mounting plate; the rear ends of the legs are fixedly connected to the rear plate, and the front ends of the legs are fixedly connected to the front plate;

[0011] Three driving mechanisms, each driving mechanism includes a chute, a slider, and a lead screw driven by a motor; the chute is laid on the leg; the slider is slidably arranged on the chute, the lead screw is located inside the chute, and the lead screw penetrates through the slider; the lead screw is in threaded cooperation with the slider, and the motor is located at the rear end of the chute;

[0012] A moving platform mechanism, which includes a moving platform and three driving link chains, and each driving link chain corresponds to a driving mechanism; the driving link chain includes a connecting rod and a spherical hinge, the rear end of the connecting rod is connected to its corresponding slider through a spherical hinge, and the front end of the connecting rod is connected to the moving platform through a spherical hinge; the extension lines of the three driving link chains intersect at one point;

[0013] A milling cutter, which is arranged on the front side of the moving platform and faces the planar thin-walled member.

[0014] In this specification, the direction towards the planar thin-walled member is "front", and the side facing the planar thin-walled member is "front side".

[0015] In the present invention, the milling device is a three-degree-of-freedom translational parallel mechanism, which changes the rotating pair of the Delta mechanism into a moving pair to become a linear Delta mechanism, that is, 3-P(SS) 2 , thereby shortening the motion chain and increasing the rigidity. The three-degree-of-freedom translational parallel mechanism in the present invention can drive the spindle to move in the XYZ directions and has the characteristics of high rigidity, which can meet the requirements of milling processing.

[0016] In the present invention, the supporting device is a serial mechanism. On the one hand, the supporting task does not require the high-precision and high-rigidity requirements of the parallel / hybrid manipulator used for the processing task. On the other hand, the advantage of the larger working space of the serial mechanism ensures the smooth progress of the collaborative supporting motion.

[0017] According to a specific embodiment of the present invention, the rear plate is triangular, and the connection points of its triangular vertices with the legs are suspended outside the vertical mounting plate; the rear ends of the three legs are fixedly connected to the triangular vertices of the rear plate.

[0018] According to a specific embodiment of the present invention, the extension lines of the three driving branch chains intersect at one point.

[0019] According to a specific embodiment of the present invention, each driving branch chain includes two parallel and synchronously moving connecting rods. If one connecting rod is used, the support for the moving platform is point support; when two connecting rods are used instead, the support for the moving platform is line support, which can improve stiffness and stability.

[0020] According to a specific embodiment of the present invention, the normal vector of the support end is always mirror-symmetrical with respect to the normal vector of the milling cutter about the planar thin-walled member, which is convenient for improving the local stiffness in the machining tip region of the large planar thin-walled member.

[0021] According to a specific embodiment of the present invention, the three-degree-of-freedom three-coordinate slide is a three-coordinate Cartesian slide, which includes a front-back axis guide rail, an up-down axis guide rail, and a left-right axis guide rail; the up-down axis guide rail is installed on the front-back axis guide rail, the left-right axis guide rail is installed on the up-down axis guide rail, and the support end is installed on the left-right axis guide rail. The three-degree-of-freedom three-coordinate slide is composed of three linear guide rails, which can achieve large-range movement in the XYZ axes, ensuring the reachability of the support movement; using a three-coordinate Cartesian slide to achieve movement in the XYZ directions has the characteristics of a large working space and convenient control.

[0022] According to a specific embodiment of the present invention, the front-back axis guide rail, the up-down axis guide rail, and the left-right axis guide rail are all provided with a motor-driven lead screw-slider mechanism.

[0023] According to a specific embodiment of the present invention, the support end includes a needle-shaped cylinder array and a six-axis force sensor; the six-axis force sensor is arranged behind the needle-shaped cylinder array. The six-axis force sensor is arranged behind the needle-shaped cylinder array, which can measure the external force received at the end of the support arm in real time.

[0024] According to a specific embodiment of the present invention, the needle-shaped cylinder array includes nine needle-shaped cylinders, and its arrangement is a central and annular arrangement. The needle-shaped cylinders are arranged in a central and annular arrangement, which can effectively improve the local stiffness, suppress workpiece deformation and machining chatter in the machining area.

[0025] There are many mature mirror milling fixtures in the prior art, which will not be elaborated here.

[0026] The present invention has the following beneficial effects:

[0027] The heterogeneous mirror milling system of the present invention gives full play to the complementary performance of the serial mechanism and the parallel mechanism, solves the disadvantages of the serial mechanism in machining, such as low rigidity, poor precision, and weak load-bearing capacity, and ensures the machining precision; the parallel mechanism has translational degrees of freedom in the X, Y, and Z directions, can control the change of the tool position, and meets the requirements for machining plane thin-walled components; the serial mechanism with a larger working space and better operability is used to complete the support task, ensuring the flexibility of the cooperative support movement.

[0028] In order to more clearly illustrate the purpose, technical solution and advantages of the present invention, the present invention will be further described in detail below with reference to the accompanying drawings and specific embodiments. Brief Description of the Drawings

[0029] Figure 1 It is the overall structure diagram and the usage state diagram of the heterogeneous mirror milling system of Embodiment 1;

[0030] Figure 2 It is the structure diagram of the fixed platform mechanism in the milling device of Embodiment 1;

[0031] Figure 3 It is the cooperation relationship diagram of the base and the fixed platform mechanism in the milling device of Embodiment 1;

[0032] Figure 4 It is the cooperation relationship diagram of the fixed platform mechanism, the driving mechanism and the moving platform mechanism in the milling device of Embodiment 1;

[0033] Figure 5 It is the cooperation relationship diagram of the driving mechanism and the moving platform mechanism in the milling device of Embodiment 1;

[0034] Figure 6 It is the structure diagram of the driving mechanism in the milling device of Embodiment 1;

[0035] Figure 7 It is the exploded view of the milling device in Embodiment 1;

[0036] Figure 8 It is the structure diagram of the support device in Embodiment 1. Detailed Description of the Embodiments

[0037] In the following description, many specific details are set forth in conjunction with the embodiments to facilitate a full understanding of the present invention. However, it should be understood that the following embodiments and detailed description are for illustrative purposes only and do not limit the scope of protection of the present invention.

[0038] Embodiment 1

[0039] As Figures 1-8As shown in the figure, this embodiment provides a heterogeneous mirror milling system for milling a planar thin-walled component A. The heterogeneous mirror milling system includes a milling device 1, a supporting device 2, and a clamping device. The clamping device clamps the planar thin-walled component. The milling device 1 and the supporting device 2 are respectively located on the front and back sides of the planar thin-walled component A. The milling device 1 is a three-degree-of-freedom translational parallel mechanism. The supporting device 2 is a serial mechanism, which includes a three-degree-of-freedom three-coordinate slide table 21 and a supporting end 22.

[0040] The milling device 1 includes: a base 11, a fixed platform mechanism 12, three driving mechanisms 13, a moving platform mechanism 14, and a milling cutter 15.

[0041] The base 11 includes a vertical mounting plate 111, and the front side of the vertical mounting plate 111 faces the planar thin-walled component A.

[0042] The fixed platform mechanism 12 includes a front plate 121, a rear plate 122, and three legs 123. The rear plate 122 is fixedly arranged on the front side of the vertical mounting plate 111. The rear ends of the legs 123 are fixedly connected to the rear plate 122, and the front ends of the legs 123 are fixedly connected to the front plate 121. The rear plate 122 is triangular, and the connection points of its triangular vertices with the legs 123 are suspended outside the vertical mounting plate 111. The rear ends of the three legs 123 are fixedly connected to the triangular vertices of the rear plate 122. The front plate 121 is circular.

[0043] Each driving mechanism 13 includes a chute 131, a slider 132, and a lead screw 134 driven by a motor 133. The chute 131 is laid on the leg 123. The slider 132 is slidably arranged on the chute 131. The lead screw 134 is located inside the chute 131, and the lead screw 134 penetrates through the slider 132. The lead screw 134 is in threaded cooperation with the slider 132, and the motor 133 is located at the rear end of the chute 131.

[0044] The moving platform mechanism 14 includes a moving platform 141 and three driving link chains 142. Each driving link chain 142 corresponds to a driving mechanism 13. The driving link chain 142 includes a ball joint 143 and two parallel and synchronously moving connecting rods 144. The rear end of the connecting rod 144 is connected to its corresponding slider 132 through the ball joint 143, and the front end of the connecting rod 144 is connected to the moving platform 141 through the ball joint 143. The extension lines of the three driving link chains 142 intersect at a point.

[0045] The milling cutter 15 is arranged on the front side of the moving platform 141 and faces the planar thin-walled component A.

[0046] The three-degree-of-freedom three-coordinate slide 21 is a three-coordinate Cartesian slide, which includes a front-back axis guide rail 211, an up-down axis guide rail 212, and a left-right axis guide rail 213; the up-down axis guide rail 212 is installed on the front-back axis guide rail 211, the left-right axis guide rail 213 is installed on the up-down axis guide rail 212, and the support end 22 is installed on the left-right axis guide rail 213. The front-back axis guide rail 211, the up-down axis guide rail 212, and the left-right axis guide rail 213 are all provided with a motor-driven lead screw-slider mechanism. The support end 22 includes a needle-shaped cylinder array 221 and a six-axis force sensor 222; the six-axis force sensor 222 is arranged behind the needle-shaped cylinder array 221. The needle-shaped cylinder array 221 includes nine needle-shaped cylinders 223, and its arrangement is in a central and annular layout. The normal vector of the support end 22 is always mirror-symmetrical with respect to the normal vector of the milling cutter 15 about the planar thin-walled member A.

[0047] The clamping device includes two clamping columns and several (for example, six, three on each side) workpiece clamps. Vertical chutes are provided on the clamping columns; the workpiece clamps include vertical sliders and vise mechanisms, and the vertical sliders are slidably arranged within the vertical chutes; after the vertical sliders slide into place, their positions are fixed by bolts.

[0048] The vise mechanism includes a long strip-shaped housing, a fixed jaw, a movable jaw, and a manual lead screw; the fixed jaw includes a connecting part and a jaw part, the connecting part is fixedly connected to the vertical slider, and the connecting part is provided with a through hole; the long strip-shaped housing includes a jaw end and a free end, and an internal slider is arranged therein; the movable jaw is arranged at the jaw end and is arranged opposite to the fixed jaw, and the long strip-shaped housing passes through the through hole; the manual lead screw includes a lead screw part and a handle part, the lead screw part is located within the long strip-shaped housing and passes through the internal slider, the lead screw part is in threaded cooperation with the internal slider, and the handle part is located outside the jaw end of the long strip-shaped housing.

[0049] Although the present invention has been depicted above through embodiments, the above embodiments are only used to exemplarily describe the feasible implementation schemes of the present invention, rather than to limit the protection scope of the present invention. Any equivalent substitution or change made by those skilled in the art in accordance with the present invention should also be covered by the protection scope defined by the claims of the present invention.

Claims

1. A heterogeneous mirror milling system for milling a planar thin-walled component, the heterogeneous mirror milling system comprising a milling device, a support device, and a clamping device; the clamping device clamps the planar thin-walled component, and the milling device and the support device are respectively located on the front and back sides of the planar thin-walled component; characterized in that, The milling device is a three-degree-of-freedom translational parallel mechanism; The supporting device is a serial mechanism, which includes a three-degree-of-freedom three-coordinate slide and a supporting end; The milling device includes: A base, which includes a vertical mounting plate, and the front of the vertical mounting plate faces the planar thin-walled component; A fixed platform mechanism, which includes a front plate, a rear plate, and three legs; the rear plate is fixedly arranged on the front of the vertical mounting plate; the rear ends of the legs are fixedly connected to the rear plate, and the front ends of the legs are fixedly connected to the front plate; Three driving mechanisms, each driving mechanism includes a chute, a slider, and a motor-driven lead screw. The chute is laid on the leg; the slider is slidably arranged on the chute, the lead screw is located within the chute, and the lead screw penetrates through the slider; the lead screw is in threaded cooperation with the slider, and the motor is located at the rear end of the chute; A moving platform mechanism, which includes a moving platform and three driving chains. Each driving chain corresponds to one of the driving mechanisms; the driving chain includes a connecting rod and a ball joint. The rear end of the connecting rod is connected to the corresponding slider through the ball joint, and the front end of the connecting rod is connected to the moving platform through the ball joint; A milling cutter, which is arranged on the front of the moving platform and faces the planar thin-walled component.

2. The heterogeneous mirror milling system according to claim 1, wherein, The rear plate is triangular, and the connection points of its three vertices with the legs are suspended outside the vertical mounting plate; the rear ends of the three legs are fixedly connected to the triangular vertices of the rear plate.

3. The heterogeneous mirror milling system according to claim 1, characterized in that, The extension lines of the three driving chains intersect at one point.

4. The heterogeneous mirror milling system according to claim 1, characterized in that, Each driving chain includes two parallel and synchronously moving connecting rods.

5. The heterogeneous mirror milling system according to claim 1, characterized in that, The normal vector of the supporting end is always in a mirror image relationship with respect to the normal vector of the milling cutter about the planar thin-walled component.

6. The heterogeneous mirror milling system according to claim 1, characterized in that, The three-degree-of-freedom three-coordinate slide is a three-coordinate Cartesian slide, which includes a front-back axis guide rail, an up-down axis guide rail, and a left-right axis guide rail; the up-down axis guide rail is installed on the front-back axis guide rail, the left-right axis guide rail is installed on the up-down axis guide rail, and the supporting end is installed on the left-right axis guide rail.

7. The heterogeneous mirror milling system according to claim 6, wherein, Motor-driven lead screw-slider mechanisms are provided on the front-back axis guide rail, the up-down axis guide rail, and the left-right axis guide rail.

8. The heterogeneous mirror milling system according to claim 6, wherein The supporting end includes a needle-shaped cylinder array and a six-axis force sensor; the six-axis force sensor is arranged behind the needle-shaped cylinder array.

9. The heterogeneous mirror milling system according to claim 7, wherein The needle-shaped cylinder array includes nine needle-shaped cylinders, and their arrangement is in a central and annular layout.

Images