A high-precision polishing machine tool

Abstract

The present invention provides a high-precision polishing machine tool, which belongs to free-form surface polishing technology equipment. The polishing machine tool includes a grinding head adjustment device, which is composed of a polishing airbag grinding head, a first hydraulic chuck, a BH connecting tower, an electric spindle H axis, a first pulley, a second pulley, a B axis motor, an AB connecting tower, an A axis rotary joint and an A axis motor. The present invention proposes a multi-degree-of-freedom, lightweight, high-workpiece axis speed free-form surface high-precision polishing machine tool, which can realize the movement of the spindle to any position within the size limit of the machine tool through multi-degree-of-freedom movement, and complete the high-precision polishing of the free-form surface.

Description

Technical Field

[0001] The invention belongs to free-form surface polishing technical equipment, and in particular relates to a high-precision polishing machine tool. Background Art

[0002] With the development of artificial intelligence and wearable devices and the trend of high-tech competition among major countries, the demand for optical free-form surfaces and arbitrary free-form surface molds is increasing. Therefore, polishing equipment that can make optical free-form surfaces and arbitrary free-form surface injection molds has become a key issue. In order to achieve the polishing of arbitrary free-form surfaces, the polishing head must be able to move in multiple degrees of freedom in the workpiece.

[0003] In the prior art, especially the six-degree-of-freedom polishing machine, although it can realize the free-form surface processing of six degrees of freedom, there are still the following problems: the workpiece axis is generally placed horizontally, and its normal direction is perpendicular to the ground. Due to gravity and vacuum adsorption of the workpiece, the polishing liquid will enter the vacuum pipeline, and there is a risk of blocking the vacuum during processing, thereby causing damage to the processed workpiece or machine tool; secondly, the moving axis of the machine tool generally slides on the connecting rod, and the accuracy of the structure is lower than that of the direct rotating shaft method, so the processing accuracy of the mechanism will also be affected. Finally, because the entire mechanism is too large, the load on the bearing shaft is very large. When the speed required by the bearing shaft is too high, the torque will be too large. Therefore, the upper limit of the rotation speed of the shaft is low, and the processing efficiency will be reduced during processing. In addition, due to the large dead weight of the mechanism, the driving motor power also needs to be very high, the cost is expensive and the assembly is extremely difficult. Summary of the invention

[0004] The present invention proposes a high-precision free-form surface polishing machine tool with multiple degrees of freedom, light weight and high workpiece axis speed. The machine tool can realize the movement of the spindle to any position within the size limit of the machine tool through multi-degree-of-freedom movement, thereby completing the high-precision polishing of the free-form surface.

[0005] To achieve the above object, the embodiments of the present invention adopt the following technical solutions:

[0006] A high-precision polishing machine tool includes a grinding head adjustment device, which is composed of a polishing airbag grinding head, a first hydraulic chuck, a BH connecting tower, an electric spindle H axis, a first pulley, a second pulley, a B-axis motor, an AB connecting tower, an A-axis rotary joint and an A-axis motor, wherein: the bottom of the A-axis motor is installed on the machine tool bed, and the A-axis rotary joint is installed on the top rotating shaft of the A-axis motor; the AB connecting tower is an L-shaped structure, and the lower crossbeam of the AB connecting tower can be rotatably installed on the A-axis rotary joint, and the AB connecting tower can rotate around the normal direction of the A-axis under the drive of the A-axis motor; the B-axis motor is installed in the lower crossbeam of the AB connecting tower The second pulley is installed on the rotating shaft of the B-axis motor; the BH connecting tower is rotatably installed on the top of the vertical beam of the AB connecting tower, the first pulley is installed on the outer end of the rotating shaft of the BH connecting tower, the first pulley and the second pulley are driven by belts, and the BH connecting tower can rotate around the normal direction of the B-axis under the drive of the B-axis motor; the H-axis of the electric spindle is tiltedly installed in the BH connecting tower, and the normal direction of the H-axis of the electric spindle H-axis and the normal direction of the B-axis of the B-axis motor form a BH-axis angle, and the range of the BH-axis angle is 40° to 50°; the first hydraulic chuck is installed at the lower part of the H-axis of the electric spindle and is used to install the polishing airbag grinding head.

[0007] Preferably, it also includes a workpiece adjustment device, which is composed of an X-axis motor, an X-axis guide rail, an X-axis screw, a Z-axis motor, a YZ connecting tower, an XY connecting tower, a C-axis motor, a Y-axis motor, a C-axis rotary joint, a Y-axis guide rail, a Y-axis screw, a Z-axis guide rail, a ZC connecting tower, a second hydraulic chuck, a Z-axis screw, The machine tool is composed of a Z-axis guide rail, wherein: the X-axis motor, the X-axis guide rail and the X-axis lead screw are installed on the machine tool bed, and the X-axis motor is coaxially connected to the X-axis lead screw; the XY connecting tower is slidably installed on the X-axis guide rail, and the lower part of the XY connecting tower is provided with a threaded hole that cooperates with the X-axis lead screw, and the XY connecting tower can move along the normal direction of the X-axis under the drive of the X-axis lead screw; the Y-axis motor is installed on the top of the XY connecting tower, and the interior of the XY connecting tower is provided with a Y-axis guide rail and a Y-axis lead screw, and the Y-axis motor is coaxially connected to the Y-axis lead screw; the YZ connecting tower is slidably installed on the Y-axis lead screw, and the YZ connecting tower is provided with a threaded hole that cooperates with the Y-axis lead screw, and the YZ connecting tower is at the Y The Z-axis motor, the Z-axis screw and the Z-axis guide rail are installed on the YZ connecting tower, and the Z-axis motor is coaxially connected to the Z-axis screw; the ZC connecting tower is slidably installed on the Z-axis guide rail, and the ZC connecting tower is provided with a threaded hole that cooperates with the Z-axis screw, and the ZC connecting tower can move along the normal direction of the Z axis under the drive of the Z-axis screw; the C-axis motor is installed on the ZC connecting tower along the normal direction of the C-axis, and the normal direction of the C-axis is parallel to the normal direction of the Z-axis; the second hydraulic chuck is installed on the rotating shaft of the C-axis motor through the C-axis rotary joint, and the second hydraulic chuck is used to clamp the tooling, and the tooling absorbs the workpiece by vacuum.

[0008] Preferably, an air pipe and a water pipe are provided inside the A-axis rotary joint, the air pipe is used to provide positive air pressure, and the water pipe is used to provide polishing liquid. The air pipe and the water pipe enter the AB connecting tower through the A-axis rotary joint, and then pass through the hollow positions of the second pulley and the first pulley in turn to enter the BH connecting tower. The water pipe is sprayed onto the polishing airbag grinding head through the water outlet of the BH connecting tower, and the air pipe inflates the interior of the polishing airbag grinding head through the H-axis of the electric spindle.

[0009] Preferably, the A-axis normal direction is parallel to the Y-axis normal direction.

[0010] Preferably, the BH axis angle is 45°.

[0011] Preferably, the normal direction of the H axis, the normal direction of the B axis, the normal direction of the A axis and the normal direction of the C axis intersect at point A in space, and the center position of the polishing airbag grinding head is set at point A.

[0012] A high-precision polishing machine tool of the present invention has the following beneficial effects:

[0013] (1) In the present invention, the workpiece axis (C axis) is placed perpendicular to the horizontal direction, that is, the normal direction is parallel to the ground. This arrangement enables the polishing liquid to flow out from the workpiece axis due to gravity when it reaches the hydraulic chuck, thereby avoiding the deposition of the polishing liquid at the hydraulic chuck, thereby solving the technical problem that the polishing liquid easily enters the workpiece axis and blocks the vacuum.

[0014] (2) The present invention uses an AB axis connecting tower so that the B axis is fixed to the AB connecting tower and rotates around a fixed axis. This rotation method replaces the sliding method in the traditional technical solution and improves the processing accuracy.

[0015] (3) The normal direction of the main axis of the present invention is at an angle of 40° to 50° with the normal direction of the B axis. This method can achieve the purpose of positioning at any spatial position while minimizing the motion range of the entire AB connecting tower mechanism.

[0016] (4) The present invention uses a C-axis motor connected to a rotary joint so that the deadweight of the rotatable mechanism of the workpiece shaft is very small and the moment of inertia is also very small, so the rotation speed of the workpiece shaft can reach more than 3000 revolutions.

[0017] (5) Due to the reduction of the deadweight and rotational inertia of the entire workpiece shaft, a smaller power motor can be selected, which also greatly reduces the space size of the entire machine tool and achieves the purpose of cost saving. BRIEF DESCRIPTION OF THE DRAWINGS

[0018] Figure 1 It is a schematic structural diagram of the first embodiment of the present invention;

[0019] Figure 2 It is a schematic structural diagram of a second embodiment of the present invention;

[0020] Figure 3 This is a schematic diagram of the ZC connection tower structure in the present invention;

[0021] Figure 4 This is a schematic diagram of the XY connection tower structure in the present invention;

[0022] Figure 5 It is a schematic diagram of the YZ connection tower structure in the present invention.

[0023] In the figure, 1-first polishing airbag grinding head, 2-first hydraulic chuck, 3-H axis normal direction, 4-BH connecting tower, 5-electric spindle H axis, 6-BH axis angle, 7-first pulley, 8-B axis normal direction, 9-second pulley, 10-B axis motor, 11-AB connecting tower, 12-A axis rotary joint, 13-A axis normal direction, 14-A axis motor, 15-X axis motor, 16-X axis normal, 17-X axis guide rail, 18-X axis Screw, 19-Z-axis motor, 20-YZ connecting tower, 21-XY connecting tower, 22-C-axis motor, 23-Y-axis motor, 24-Y-axis normal direction, 25-C-axis rotary joint, 26-C-axis normal direction, 27-Y-axis guide rail, 28-Y-axis screw, 29-first Z-axis guide rail, 30-ZC connecting tower, 31-Z-axis normal direction, 32-second hydraulic chuck, 33-Z-axis screw, 34-second Z-axis guide rail, 35-water outlet. DETAILED DESCRIPTION

[0024] In the description of the present invention, it should be understood that the terms "center", "up", "down", "front", "back", "left", "right", "vertical", "horizontal", "top", "bottom", "inside", "outside" and the like indicate positions or positional relationships based on the positions or positional relationships shown in the accompanying drawings, and are only for the convenience of describing the present invention and simplifying the description, rather than indicating or implying that the device or element referred to must have a specific orientation, be constructed and operated in a specific orientation, and therefore cannot be understood as limiting the present invention. The terms "first" and "second" are used for descriptive purposes only, and cannot be understood as indicating or implying relative importance or implicitly indicating the number of technical features indicated. Thus, the features defined as "first" and "second" may explicitly or implicitly include one or more of the features. In the description of the present invention, unless otherwise specified, "multiple" means two or more.

[0025] According to the accompanying drawings, the present invention is further described: Embodiment 1

[0026] like Figure 1 As shown, a high-precision polishing machine includes a grinding head adjustment device and a common workpiece clamping structure. The grinding head adjustment device can adjust the posture of the polishing airbag grinding head 1 within multiple degrees of freedom to achieve optical free-form surface processing. Generally, a vacuum adsorption structure is used to fix the workpiece.

[0027] Figure 1 In the figure, the grinding head adjustment device is composed of a polishing airbag grinding head 1, a first hydraulic chuck 2, a BH connecting tower 4, an electric spindle H axis 5, a first pulley 7, a second pulley 9, a B axis motor 10, an AB connecting tower 11, an A axis rotary joint 12 and an A axis motor 14.

[0028] Specifically, the bottom of the A-axis motor 14 is installed on the machine tool bed, and the A-axis rotary joint 12 is installed at the top rotating shaft of the A-axis motor 14; the AB connecting tower 11 is an L-shaped structure, and the lower crossbeam of the AB connecting tower 11 is rotatably installed on the A-axis rotary joint 12. The AB connecting tower 11 can rotate around the A-axis normal direction 13 driven by the A-axis motor 14; the B-axis motor 10 is installed inside the lower crossbeam of the AB connecting tower 11, and the second pulley 9 is installed on the rotating shaft of the B-axis motor 10; the BH connecting tower 4 is rotatably installed on the top of the vertical beam of the AB connecting tower 11, and the first pulley 9 is installed on the rotating shaft of the B-axis motor 10. The pulley 7 is installed at the outer end of the rotating shaft of the BH connecting tower 4. The first pulley 7 and the second pulley 9 are driven by a belt, and the BH connecting tower 4 can rotate around the B-axis normal direction 8 under the drive of the B-axis motor 10; the electric spindle H axis 5 is tiltedly installed in the BH connecting tower 4, and a BH axis angle 6 is formed between the H-axis normal direction 3 of the electric spindle H axis 5 and the B-axis normal direction 8 of the B-axis motor 10. The range of the BH axis angle 6 is 40° to 50°, and 45° is preferably selected in this embodiment; the first hydraulic chuck 2 is installed at the lower part of the electric spindle H axis 5 and is used to install the polishing airbag grinding head 1.

[0029] It should be noted that an air pipe and a water pipe are provided inside the A-axis rotary joint 12. The air pipe is used to provide positive air pressure, and the water pipe is used to provide polishing liquid. The air pipe and the water pipe enter the AB connecting tower 11 through the A-axis rotary joint 12, and then pass through the hollow positions of the second pulley 9 and the first pulley 7 in turn to enter the BH connecting tower 4. The water pipe is sprayed onto the polishing airbag grinding head 1 through the water outlet 35 of the BH connecting tower 4, and the air pipe inflates the interior of the polishing airbag grinding head 1 through the electric spindle H axis 5.

[0030] It should be further explained that the H-axis normal direction 3 , the B-axis normal direction 8 , the A-axis normal direction 13 and the C-axis normal direction 26 intersect at point A in space, and the center position of the polishing airbag grinding head 1 is set at point A.

[0031] During actual operation: the AB connecting tower 11 can rotate around the A-axis normal direction 13 driven by the A-axis motor 14, and the BH connecting tower 4 can rotate around the B-axis normal direction 8 driven by the B-axis motor 10, and the B-axis motor 10 is transmitted to the BH connecting tower 4 by a belt and pulley transmission method.

[0032] In this embodiment, the AB axis connecting tower is used, so that the B axis is fixed to the AB connecting tower and rotates around a fixed axis. This rotation method replaces the sliding method in the traditional technical solution and improves the processing accuracy. The normal direction of the spindle and the normal direction of the B axis form an angle of 40° to 50°. This method can achieve the purpose of positioning at any spatial position and minimize the motion range of the entire AB connecting tower mechanism. Embodiment 2

[0033] On the basis of the first embodiment, a workpiece adjustment device is added, which can adjust the position and posture of the workpiece within the range of multiple degrees of freedom. Figure 2 As shown, the workpiece adjustment device is composed of an X-axis motor 15, an X-axis guide rail 17, an X-axis screw 18, a Z-axis motor 19, a YZ connecting tower 20, an XY connecting tower 21, a C-axis motor 22, a Y-axis motor 23, a C-axis rotary joint 25, a Y-axis guide rail 27, a Y-axis screw 28, a first Z-axis guide rail 29, a ZC connecting tower 30, a second hydraulic chuck 32, a Z-axis screw 33, and a second Z-axis guide rail 34.

[0034] Specifically, the X-axis motor 15, the X-axis guide rail 17 and the X-axis lead screw 18 are installed on the machine tool bed, and the X-axis motor 15 is coaxially connected to the X-axis lead screw 18; the XY connecting tower 21 is slidably installed on the X-axis guide rail 17, and the lower part of the XY connecting tower 21 is provided with a threaded hole that cooperates with the X-axis lead screw 18. The XY connecting tower 21 can move along the X-axis normal 16 under the drive of the X-axis lead screw 18; the Y-axis motor 23 is installed on the top of the XY connecting tower 21, and the interior of the XY connecting tower 21 is provided with a Y-axis guide rail 27 and a Y-axis lead screw 28, and the Y-axis motor 23 is coaxially connected to the Y-axis lead screw 28.

[0035] like Figure 3 , Figure 4 and Figure 5 As shown, the YZ connecting tower 20 is slidably mounted on the Y-axis guide rail 27, and a threaded hole cooperating with the Y-axis lead screw 28 is provided on the YZ connecting tower 20. The YZ connecting tower 20 can move along the Y-axis normal direction 24 under the drive of the Y-axis lead screw 28; the Z-axis motor 19, the Z-axis lead screw 33 and the second Z-axis guide rail 34 are mounted on the YZ connecting tower 20, and the Z-axis motor 19 is coaxially connected to the Z-axis lead screw 33; the ZC connecting tower 30 is slidably mounted on the second Z-axis guide rail 34 The ZC connecting tower 30 is provided with a threaded hole that cooperates with the Z-axis screw 33. The ZC connecting tower 30 can move along the Z-axis normal direction 31 under the drive of the Z-axis screw 33; the C-axis motor 22 is installed on the ZC connecting tower 30 along the C-axis normal direction 26, and the C-axis normal direction 26 is parallel to the Z-axis normal direction 31; the second hydraulic chuck 32 is installed on the rotating shaft of the C-axis motor 22 through the C-axis rotary joint 25, and the second hydraulic chuck 32 is used to clamp the workpiece.

[0036] It should be noted that the A-axis normal direction 13 is parallel to the Y-axis normal direction 24. The positions between the workpiece adjustment device and the grinding head adjustment device can be flexibly arranged to adapt to different workpieces.

[0037] During specific operation: the workpiece can be accurately moved within 3 degrees of freedom. First, the movement in the direction of the X-axis normal 16 is achieved by the overall movement of the workpiece adjustment device. Secondly, the movement in the direction of the Y-axis normal 24 is achieved by the cooperation of the screw and guide rail on the XY connecting tower 21. Finally, the movement in the direction of the Z-axis normal 31 is achieved by the cooperation of the screw and guide rail on the ZC connecting tower.

[0038] In this embodiment, the workpiece axis (C axis) is placed perpendicular to the horizontal direction, that is, the normal direction is parallel to the ground. This arrangement enables the polishing liquid to flow out from the workpiece axis due to gravity when it reaches the hydraulic chuck, avoiding the deposition of polishing liquid at the hydraulic chuck, thereby solving the technical problem that the polishing liquid easily enters the workpiece axis and blocks the vacuum. The way the C-axis motor is connected to the rotary joint makes the rotatable mechanism of the workpiece axis very small and the moment of inertia is also very small, so the workpiece axis speed can reach more than 3000 revolutions. Due to the reduction of the weight and moment of inertia of the entire workpiece axis, a smaller power motor can be selected, which also greatly reduces the space size of the entire machine tool, achieving the purpose of cost saving.

[0039] Finally, it should be noted that the above embodiments are only used to illustrate the technical solutions of the present invention, rather than to limit it. Although the present invention has been described in detail with reference to the aforementioned embodiments, those skilled in the art should understand that they can still modify the technical solutions described in the aforementioned embodiments, or make equivalent replacements for some of the technical features therein. However, these modifications or replacements do not deviate the essence of the corresponding technical solutions from the spirit and scope of the technical solutions of the embodiments of the present invention.

Claims

1. A high-precision polishing machine tool, characterized in that: The invention comprises a grinding head adjustment device, wherein the grinding head adjustment device comprises a polishing airbag grinding head (1), a first hydraulic chuck (2), a BH connecting tower (4), an electric spindle H axis (5), a first belt pulley (7), a second belt pulley (9), a B axis motor (10), an AB connecting tower (11), an A axis rotary joint (12) and an A axis motor (14), wherein: The bottom of the A-axis motor (14) is mounted on the machine tool bed, and the A-axis rotary joint (12) is mounted on the top rotating shaft of the A-axis motor (14); The AB connection tower (11) is of an L-shaped structure, and the lower crossbeam of the AB connection tower (11) is rotatably mounted on the A-axis rotary joint (12). The AB connection tower (11) is driven by the A-axis motor (14) to rotate around the A-axis normal direction (13); The B-axis motor (10) is installed inside the lower crossbeam of the AB connecting tower (11), and the second pulley (9) is installed on the rotating shaft of the B-axis motor (10); The BH connecting tower (4) is rotatably mounted on the top of the vertical beam of the AB connecting tower (11); the first belt pulley (7) is mounted on the outer end of the rotating shaft of the BH connecting tower (4); the first belt pulley (7) and the second belt pulley (9) are driven by a belt, and the BH connecting tower (4) can be rotated around the normal direction (8) of the B axis under the drive of the B axis motor (10); The electric spindle H axis (5) is obliquely installed in the BH connection tower (4), and a BH axis angle (6) is formed between an H axis normal direction (3) of the electric spindle H axis (5) and a B axis normal direction (8) of the B axis motor (10), and the range of the BH axis angle (6) is 40° to 50°; The first hydraulic chuck (2) is mounted on the lower part of the electric spindle H axis (5) and is used to mount the polishing airbag grinding head (1).

2. The high-precision polishing machine tool according to claim 1, characterized in that: The invention also comprises a workpiece adjustment device, wherein the workpiece adjustment device comprises an X-axis motor (15), an X-axis guide rail (17), an X-axis lead screw (18), a Z-axis motor (19), a YZ connecting tower (20), an XY connecting tower (21), a C-axis motor (22), a Y-axis motor (23), a C-axis rotary joint (25), a Y-axis guide rail (27), a Y-axis lead screw (28), a first Z-axis guide rail (29), a ZC connecting tower (30), a second hydraulic chuck (32), a Z-axis lead screw (33) and a second Z-axis guide rail (34), wherein: The X-axis motor (15), the X-axis guide rail (17) and the X-axis lead screw (18) are mounted on the machine tool bed, and the X-axis motor (15) and the X-axis lead screw (18) are coaxially connected; The XY connecting tower (21) is slidably mounted on the X-axis guide rail (17); a threaded hole cooperating with the X-axis lead screw (18) is provided at the bottom of the XY connecting tower (21); the XY connecting tower (21) is capable of moving along the direction of the X-axis normal (16) under the drive of the X-axis lead screw (18); The Y-axis motor (23) is installed on the top of the XY connection tower (21); a Y-axis guide rail (27) and a Y-axis lead screw (28) are arranged inside the XY connection tower (21); the Y-axis motor (23) is coaxially connected to the Y-axis lead screw (28); The YZ connecting tower (20) is slidably mounted on the Y-axis guide rail (27); a threaded hole cooperating with the Y-axis lead screw (28) is provided on the YZ connecting tower (20); and the YZ connecting tower (20) is capable of moving along the Y-axis normal direction (24) under the drive of the Y-axis lead screw (28); The Z-axis motor (19), the Z-axis lead screw (33) and the second Z-axis guide rail (34) are mounted on the YZ connecting tower (20), and the Z-axis motor (19) is coaxially connected to the Z-axis lead screw (33); The ZC connecting tower (30) is slidably mounted on the second Z-axis guide rail (34); a threaded hole cooperating with the Z-axis lead screw (33) is provided on the ZC connecting tower (30); and the ZC connecting tower (30) is capable of moving along the Z-axis normal direction (31) under the drive of the Z-axis lead screw (33); The C-axis motor (22) is mounted on the ZC connection tower (30) along the C-axis normal direction (26), and the C-axis normal direction (26) and the Z-axis normal direction (31) are parallel; The second hydraulic chuck (32) is mounted on the rotating shaft of the C-axis motor (22) via the C-axis rotary joint (25), and the second hydraulic chuck (32) is used to clamp a workpiece.

3. The high-precision polishing machine tool according to claim 2, characterized in that: An air pipe and a water pipe are arranged inside the A-axis rotary joint (12). The air pipe is used to provide positive air pressure, and the water pipe is used to provide polishing liquid. The air pipe and the water pipe enter the AB connection tower (11) through the A-axis rotary joint (12), and then pass through the hollow position of the second pulley (9) and the hollow position of the first pulley (7) in sequence to enter the BH connection tower (4). The water pipe is sprayed onto the polishing airbag grinding head (1) through the water outlet (35) of the BH connection tower (4), and the air pipe inflates the inside of the polishing airbag grinding head (1) through the electric spindle H axis (5).

4. The high-precision polishing machine tool according to claim 3, characterized in that: The A-axis normal direction (13) is parallel to the Y-axis normal direction (24).

5. The high-precision polishing machine tool according to claim 4, characterized in that: The BH axis angle (6) is 45°.

6. The high-precision polishing machine tool according to claim 5, characterized in that: The H-axis normal direction (3), the B-axis normal direction (8), the A-axis normal direction (13), and the C-axis normal direction (26) intersect at point A in space, and the center position of the polishing airbag grinding head (1) is set at point A.

Images