A force error measuring device and a measuring method thereof

Abstract

The application relates to a force-induced error measuring device and a measuring method thereof, and relates to the technical field of precision machining. The application is used for solving the problem that the error of an existing machine tool under the influence of cutting force and workpiece load is difficult to measure. The application comprises a machine tool main body, a fixed frame, a force loading device, a force measuring device, a receiving end module and a transmitting end module. The force measuring device is fixedly connected to a workbench of the machine tool main body. The fixed frame is vertically fixedly connected to a bed of the machine tool main body along a Y-axis direction. The force loading device is arranged on the fixed frame. A loading end of the force loading device is arranged towards the force measuring device and applies force along the Y-axis direction. The loading end of the force loading device can be moved along an X-axis direction, a Y-axis direction and a Z-axis direction respectively. The transmitting end module is fixedly connected to the bed of the machine tool main body. The receiving end module is fixedly connected to the workbench of the machine tool main body. The application is used for measuring the error of the machine tool under the action of force load.

Description

Technical Field

[0001] This invention relates to the field of precision machining technology, and more specifically to a force-induced error measuring device and its measuring method. Background Technology

[0002] With the continuous development of the social economy and the increasing demands for product quality, the requirements for ultra-precision machining technology are also constantly rising. Currently, as the requirements for workpiece surface finish quality continue to increase, the demands on machine tool processing capabilities are also constantly rising. Machine tool error is the most important factor affecting machine tool performance. While error measurement of machine tools under quasi-static conditions is quite mature, error measurement under the influence of cutting forces and workpiece loads remains largely unexplored. To address the existing problem of force-induced error measurement, this invention proposes a novel force measuring device, combined with corresponding measurement methods, to accurately measure the changes in machine tool error under various force and torque loading conditions. This lays the foundation for subsequent force-induced error measurement, thereby improving the machining accuracy of machine tools. Summary of the Invention

[0003] In order to solve the problem that it is difficult to measure the error of existing machine tools under the influence of cutting force and workpiece load, this invention proposes a force-induced error measuring device and its measuring method.

[0004] The technical solution adopted by the present invention to solve the above-mentioned technical problems is as follows:

[0005] A force-induced error measuring device includes a machine tool body, a fixed frame, a force loading device, a force measuring device, a receiving module, and a transmitting module. The force measuring device is fixedly connected to the worktable of the machine tool body. The fixed frame is vertically fixed to the bed of the machine tool body along the Y-axis. The force loading device is disposed on the fixed frame, with its loading end facing the force measuring device and applying force along the Y-axis. The loading end of the force loading device can move along the X-axis, Y-axis, and Z-axis, respectively. The transmitting module is fixedly connected to the bed of the machine tool body, and the receiving module is fixedly connected to the worktable of the machine tool body.

[0006] Furthermore, the fixed frame is an aluminum profile frame, and the force loading device can move along the Y-axis on the fixed frame.

[0007] Furthermore, the force loading device includes an X-axis linear motion component, a Z-axis linear motion component, and a force loading component. The X-axis linear motion component is mounted on a fixed frame, and the force loading component is connected to the execution end of the X-axis linear motion component through the Z-axis linear motion component. The force loading component is positioned along the Y-axis direction.

[0008] Furthermore, the force loading assembly includes a bullseye wheel, a spring, an electric cylinder, and two arc-shaped guide plates. The electric cylinder is fixedly connected to the execution end of the Z-axis linear motion assembly. The two arc-shaped guide plates are fixedly connected to each other and spliced ​​into a cylindrical sleeve. The cylindrical sleeve is fitted onto the outside of the execution end of the electric cylinder rod. The bullseye wheel is located at the front end inside the cylindrical sleeve, and the spring is located inside the cylindrical sleeve. The bullseye wheel is connected to the execution end of the electric cylinder rod through the spring.

[0009] Furthermore, the Z-axis linear motion assembly includes a Z-axis displacement plate and a Z-axis fixing plate. The Z-axis fixing plate is vertically fixed to the execution end of the X-axis linear motion assembly. The Z-axis displacement plate is the execution end of the Z-axis linear motion assembly. The Z-axis fixing plate is provided with multiple sets of connecting holes evenly distributed along the vertical direction. The Z-axis displacement plate is provided with multiple sets of through holes evenly distributed along the vertical direction. The through holes and connecting holes are correspondingly set and connected by connecting bolts. The connection between different through holes and connecting holes realizes the adjustment of the Z-axis displacement plate along the Z-axis direction.

[0010] Furthermore, the X-axis linear motion assembly includes an X-axis linear module and two L-shaped fixing plates. The two L-shaped fixing plates are arranged opposite to each other. The vertical ends of the L-shaped fixing plates are fixed to the fixed frame by tightening bolts. The X-axis linear module is fixed to the horizontal ends of the two L-shaped fixing plates. The slide of the X-axis linear module is the execution end of the X-axis linear motion assembly.

[0011] Furthermore, the force measuring device includes an L-shaped aluminum plate, a six-dimensional force sensor, and a horizontal platform. The horizontal platform is fixed to the worktable of the machine tool body, the six-dimensional force sensor is set on the horizontal platform, the horizontal end of the L-shaped aluminum plate is connected to the six-dimensional force sensor, and the opening of the L-shaped aluminum plate is set towards the force loading device.

[0012] Furthermore, the transmitting module includes an interferometer transmitting end, a transmitting end connecting L-plate, a Z-axis long displacement linear slide, an X-axis long displacement linear slide, a transmitting end connecting plate, an n-shaped support, and a transmitting end bracket. The transmitting end bracket is fixed to the bed of the machine tool body. The transmitting end connecting plate is fixed to the transmitting end bracket via the n-shaped support. The X-axis long displacement linear slide is set on the transmitting end connecting plate along the X-axis direction. The Z-axis long displacement linear slide is set on the slider of the X-axis long displacement linear slide along the Z-axis direction. The vertical end of the transmitting end connecting L-plate is fixed to the slider of the Z-axis long displacement linear slide. The interferometer transmitting end is fixed to the horizontal end of the transmitting end connecting L-plate.

[0013] Furthermore, the receiving module includes an interferometer receiver, a receiving connecting plate, a pitch rotation module, a yaw rotation module, a receiving T-shaped connecting plate, and a receiving Z-axis micro-displacement stage. The receiving Z-axis micro-displacement stage is fixedly connected to the worktable of the machine tool body. The horizontal end of the receiving T-shaped connecting plate is fixedly connected to the moving block of the receiving Z-axis micro-displacement stage. The inner end of the receiving connecting plate is connected to the vertical end of the receiving T-shaped connecting plate in sequence through the pitch rotation module and the yaw rotation module. The interferometer receiver is fixedly connected to the outer end of the receiving connecting plate.

[0014] A measurement method based on a force-induced error measuring device includes the following steps:

[0015] Step 1, Pre-adjustment: Before starting the measurement, install the receiving module and the transmitting module on the worktable and bed of the machine tool body, respectively, and adjust the pose of the interferometer receiver and the interferometer transmitter to ensure good optical path; the force loading device adjusts the moving distance of the electric cylinder to apply a constant Y-axis force to the L-shaped aluminum plate, and adjusts the torque around the Y-axis and around the Z-axis by adjusting the X-axis linear module and the Z-axis displacement plate; the six-dimensional force sensor senses the force and torque in real time;

[0016] Step 2, Measurement Stage: Set the machining area to 100mm × 100mm. Take a measurement point every 10mm along the X and Y axes of the machine tool, generating a total of 10 × 10 = 100 fixed measurement points. When the machine tool is subjected to a force in the Y direction, install the transmitter and receiver modules on the machine tool's front side. Move the machine tool's X and Y axes until they stop at X=0mm and Y=0mm, respectively. Control the magnitude and position of the X-axis force applied by the force loading device. This will generate an X-axis force and torques around the Z and X axes. Different force and torque parameters can be obtained through a six-dimensional force sensor during and after the movement. During this process, the force applied by the force loading device remains constant. By controlling the X-axis movement, the machine tool is moved sequentially to ten fixed measurement points in the range of [0mm, 0mm~100mm]. At each fixed measurement point, the machine stays for 5 seconds, and the force and torque parameters are recorded by a six-dimensional force sensor. The force error is measured and recorded by an interferometer, thus obtaining the force error parameters in the range of [0mm, 0mm~100mm]. When this set of force error measurements is completed, the force and torque parameters can be changed by altering the displacement of the electric cylinder and the connection of the Z-axis displacement plate, and by moving the X-axis linear module. This allows for the uniform measurement of force error parameters under multiple sets of force and torque parameters.

[0017] When the X=0mm data measurement is completed, move the X-axis to move the machine tool to X=10mm. At this time, the receiving module moves to X=10mm along the X-axis. Move the X-axis long displacement linear slide of the transmitting module to align the interferometer receiving end and the interferometer transmitting end. If the optical path is not good at this time, the pose of the receiving module and the moving transmitting module can be adjusted. Continue to measure the force-induced error parameters of ten points on [10mm, 0mm~100mm] according to the above method. Through this method, ten sets of force-induced error parameters caused by Y-axis force from 0mm to 100mm are obtained in sequence.

[0018] After measuring the force-induced error parameters caused by the Y-axis force, rotate the L-shaped aluminum plate 90 degrees and fix it. Adjust the position of the force loading device to apply an X-axis force to the machine tool. Move the Y-axis and repeat the above steps to obtain the error data after the X-axis force is applied.

[0019] The beneficial effects of this invention compared to the prior art are:

[0020] The force loading device of this invention can apply a constant force to an L-shaped aluminum plate in a specific direction. By controlling the displacement time of the electric cylinder, the compression displacement of the compression spring is controlled, thereby controlling the magnitude of the applied force. The compression spring applies force to the L-shaped aluminum plate through a bullseye wheel. When the machine tool axis drives the L-shaped aluminum plate to move, the bullseye wheel balls roll, reducing the influence of friction on the force loading device. At the same time, the displacement of the force loading device in the direction other than the applied force is constrained by two cylindrical sleeves, thus maintaining its own position. The electric cylinder is connected to a Z-axis displacement plate, which has two rows of eight bolt holes arranged at equal intervals. It can be connected to the Z-axis fixing plate at different heights, allowing the electric cylinder to move its Z-axis position at equal intervals, thereby generating different torques around the X-axis or Y-axis. The Z-axis fixing plate is connected to the X-axis linear module, and its lateral distance can be adjusted to generate different torques around the Z-axis.

[0021] This invention directly fixes the six-dimensional force sensor to the machine tool connecting plate, which is then fixed to the machine tool. An L-shaped aluminum plate is connected to the six-dimensional force sensor. The bullseye wheel of the force loading device can move laterally along its surface, and the L-shaped aluminum plate can be rotated and fixed around the machine tool's Z-axis, thereby allowing the application of forces in the X and Y directions.

[0022] The difficulty in force-induced error measurement lies in the fact that the two modules of the interferometer need to be adjusted multiple times during the measurement process. The adjustment of the interferometer's posture is complex, and the posture adjustment tools initially provided by the manufacturer, especially the adjustment tools at the receiving end, are inconvenient, requiring skilled mastery and unable to handle adjustments requiring multiple short displacements. Therefore, this invention designs adjustment modules for the receiving and transmitting ends of the interferometer to match the force measurement frame.

[0023] The receiver module achieves quantitative fine-tuning and fixation in both pitch and yaw directions through two rotating modules, and three-angle fine-tuning through its built-in rotating module. The receiver module, via its Z-axis module and in conjunction with the machine tool's X or Y-axis movement, enables adjustment and fixation in other linear directions besides the measurement direction. The receiver module design eliminates the cumbersome and inefficient optical path adjustment steps of traditional interferometer measurements, and enables rapid adjustment of the optical path through multiple short displacements during force-induced error measurements, improving adjustment efficiency and accuracy.

[0024] The design of the interferometer transmitter module mainly addresses the problem of adjusting multiple short displacements during force-induced error measurement. Although the transmitter has built-in fine-tuning devices in the Z and X directions, their strokes are too short to meet the measurement requirements. The transmitter adjustment module uses an X-axis module with a stroke of 150mm and a Z-axis module with a stroke of 150mm to meet the requirement of multiple short displacements during the measurement process.

[0025] The measurement method of this invention uses a Renishaw interferometer XM80, which can measure the error of six degrees of freedom at once. This measurement method can measure the force-induced error of the entire processing area. Attached Figure Description

[0026] Figure 1 This is a schematic diagram of the structure of a force-induced error measuring device according to the present invention;

[0027] Figure 2 This is an exploded structural diagram of a force-induced error measuring device according to the present invention.

[0028] Figure 3 This is a schematic diagram of the force measuring device in this invention;

[0029] Figure 4 This is an exploded structural diagram of the force measuring device in this invention;

[0030] Figure 5 This is a schematic diagram of the Z-axis linear motion component and force loading component in this invention;

[0031] Figure 6 This is an exploded structural diagram of the Z-axis linear motion component and the force loading component in this invention;

[0032] Figure 7 This is a schematic diagram of the X-axis linear motion component in this invention;

[0033] Figure 8 This is an exploded structural diagram of the X-axis linear motion component in this invention;

[0034] Figure 9 This is a schematic diagram of the transmitter module in this invention;

[0035] Figure 10 This is an exploded structural diagram of the transmitter module in this invention;

[0036] Figure 11 This is a schematic diagram of the receiving module in this invention;

[0037] Figure 12 This is an exploded structural diagram of the receiving module in this invention. Detailed Implementation

[0038] To make the technical problems solved, the technical solutions, and the beneficial effects of the present invention clearer, the invention will be further described in detail below with reference to the accompanying drawings and embodiments. It should be understood that the specific embodiments described herein are only for explaining the invention and are not intended to limit the invention.

[0039] Specific implementation method one: Combining Figures 1 to 12 This embodiment describes a force-induced error measuring device, characterized in that it includes a machine tool body 1, a fixed frame 2, a force loading device 3, a force measuring device 4, a receiving module 5, and a transmitting module 6. The force measuring device 4 is fixedly connected to the worktable of the machine tool body 1. The fixed frame 2 is vertically fixed to the bed of the machine tool body 1 along the Y-axis direction. The force loading device 3 is disposed on the fixed frame 2. The loading end of the force loading device 3 is positioned towards the force measuring device 4 and applies force along the Y-axis direction. The loading end of the force loading device 3 can move along the X-axis direction, the Y-axis direction, and the Z-axis direction, respectively. The transmitting module 6 is fixedly connected to the bed of the machine tool body 1, and the receiving module 5 is fixedly connected to the worktable of the machine tool body 1.

[0040] In this embodiment, the fixed frame 2 can be used to fix the force loading device 3; the force loading device 3 realizes the conversion and adjustment of different loading points during the force loading process; the force measuring device 4 can measure the force loading at different points; the receiving module 5 is fixed on the worktable and the optical path can be adjusted during the measurement; the transmitting module 6 can realize the movement of the transmitting end in the X and Z axis directions, ensuring that the measurement can still be performed after the machine tool position is moved by adjusting the position.

[0041] The assembly steps of the error measuring device are as follows:

[0042] First, following the parts arrangement and assembly diagram mentioned earlier, assemble each part separately using the corresponding screws, including the force measuring device 4, the fixing frame 2, the force loading device 3, the receiver module 5, and the transmitter module 6. Then, assemble the whole unit in the following order:

[0043] 1. Install the force measuring device 4 onto the machine tool worktable;

[0044] 2. Install receiver module 5. Do not install receiver module 5 onto the machine tool body 1 at this time.

[0045] 3. Install the force loading module 3 onto the fixed frame 2 and leave sufficient space between the lower half and the workpiece for installation;

[0046] 4. Install the fixing frame 2 onto the machine tool body 1;

[0047] 5. Install the force loading device 3, and adjust the position of the force loading device 3 so that the bullseye wheel 31 is tangent to the L-shaped aluminum plate 41;

[0048] 6. Install transmitter module 6 onto the bed;

[0049] 7. Install receiver module 5.

[0050] Specific Implementation Method Two: Combining Figures 1 to 12 This embodiment describes a fixed frame 2 made of aluminum profile, and a force loading device 3 that can move along the Y-axis on the fixed frame 2.

[0051] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment 1.

[0052] Due to the structural characteristics of aluminum profiles, the force loading device 3 can move along the Y-axis to adjust its position.

[0053] Specific implementation method three: Combining Figures 1 to 12 This embodiment describes a force loading device 3 comprising an X-axis linear motion component, a Z-axis linear motion component, and a force loading component. The X-axis linear motion component is mounted on the fixed frame 2. The force loading component is connected to the execution end of the X-axis linear motion component via the Z-axis linear motion component. The force loading component is positioned along the Y-axis direction.

[0054] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment Two.

[0055] The force loading component can be moved and adjusted along the X, Y, and Z axes.

[0056] The X-axis and Y-axis directions described in this invention are consistent with the X-axis and Y-axis directions of the machine tool, and the Z-axis direction described in this invention is the height direction of the machine tool.

[0057] Specific implementation method four: Combination Figures 1 to 12This embodiment describes a force loading assembly comprising a bullseye wheel 31, a spring 32, an electric cylinder 33, and two arc-shaped guide plates 34. The electric cylinder 33 is fixedly connected to the execution end of the Z-axis linear motion assembly. The two arc-shaped guide plates 34 are fixedly connected to each other and spliced ​​to form a cylindrical sleeve, which is fitted onto the outer side of the execution end of the electric cylinder 33 rod. The bullseye wheel 31 is located at the front end inside the cylindrical sleeve, and the spring 32 is located inside the cylindrical sleeve. The bullseye wheel 31 is connected to the execution end of the electric cylinder 33 rod through the spring 32.

[0058] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment Three.

[0059] The force loading component is centered around an electric cylinder 33 placed along the Y-axis. To ensure that the applied force is controllable, a cylindrical sleeve assembled in two halves is fixed to the main body of the electric cylinder 33. A spring 32 is placed inside the cylindrical sleeve to convert the stroke of the electric cylinder 33 into a loading force with a certain range of variation in a proportional relationship. Considering that the position of the measurement point needs to be adjustable during the measurement process, a bullseye wheel 31 is added to the end of the cylindrical sleeve, so that the force loading device can change the force loading point without unloading, thus achieving the continuity of measurement.

[0060] In this embodiment, the cylindrical sleeve is closed at the front end and open at the rear end. A through hole is opened in the middle of the front end face of the cylindrical sleeve. A connecting shaft is vertically fixed to the rear end of the bullseye wheel 31. After the connecting shaft passes through the through hole, a nut is threadedly connected to it. The rear end of the nut is fixed to the front end of the spring 32.

[0061] Specific Implementation Method Five: Combining Figures 1 to 12 This embodiment describes a Z-axis linear motion assembly comprising a Z-axis displacement plate 35 and a Z-axis fixing plate 36. The Z-axis fixing plate 36 is vertically fixed to the execution end of the X-axis linear motion assembly. The Z-axis displacement plate 35 is the execution end of the Z-axis linear motion assembly. The Z-axis fixing plate 36 has multiple sets of connecting holes 361 evenly distributed along the vertical direction, and the Z-axis displacement plate 35 has multiple sets of through holes 351 evenly distributed along the vertical direction. The through holes 351 and the connecting holes 361 are correspondingly arranged and connected by connecting bolts. The connection between different through holes 351 and the connecting holes 361 enables the adjustment of the Z-axis displacement plate 35 along the Z-axis direction.

[0062] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment Three.

[0063] The force loading device 3 is adjusted along the Z-axis via a set of two T-shaped perforated plates with reinforcing ribs: a Z-axis displacement plate 35 and a Z-axis fixing plate 36. The holes are distributed in two rows along the Z-axis, totaling eight M4 holes. By selecting different fixing hole positions, three height adjustments can be achieved in the Z-axis direction, with each height change being equal.

[0064] Specific Implementation Method Six: Combination Figures 1 to 12 This embodiment describes an X-axis linear motion assembly comprising an X-axis linear module 37 and two L-shaped fixing plates 38. The two L-shaped fixing plates 38 are arranged opposite to each other, and the vertical ends of the L-shaped fixing plates 38 are fixed to the fixing frame 2 by tightening bolts. The X-axis linear module 37 is fixed to the horizontal ends of the two L-shaped fixing plates 38, and the slide of the X-axis linear module 37 is the execution end of the X-axis linear motion assembly.

[0065] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment Three.

[0066] The force loading device 3 is adjusted in the X-axis direction using a set of lead screw slides fixed on the aluminum profile frame, namely the X-axis linear module 37, which can achieve continuous and measurable position changes. During installation, the X-axis linear module 37 uses two centrally located L-shaped fixing plates 38 with reinforcing ribs. The long side is connected to the X-axis linear module 37, and the short side is connected to the aluminum profile frame. The two L-shaped fixing plates 38 are placed opposite each other. Due to the structural characteristics of the aluminum profile, the loading device can move along the Y-axis direction to adjust the position of the force loading device.

[0067] Specific implementation method seven: Combination Figures 1 to 12 This embodiment describes a force measuring device 4 comprising an L-shaped aluminum plate 41, a six-dimensional force sensor 42, and a horizontal platform 43. The horizontal platform 43 is fixedly connected to the worktable of the machine tool body 1. The six-dimensional force sensor 42 is mounted on the horizontal platform 43. The horizontal end of the L-shaped aluminum plate 41 is connected to the six-dimensional force sensor 42. The opening of the L-shaped aluminum plate 41 faces the force loading device 3.

[0068] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment 1.

[0069] The L-shaped aluminum plate 41, the six-dimensional force sensor 42, and the water platform 43 are centrally aligned.

[0070] Specific implementation method eight: Combination Figures 1 to 12This embodiment describes a transmitter module 6 comprising an interferometer transmitter 61, a transmitter connecting L-plate 62, a Z-axis long displacement linear slide 63, an X-axis long displacement linear slide 64, a transmitter connecting plate 65, an n-shaped support 66, and a transmitter bracket 67. The transmitter bracket 67 is fixedly connected to the bed of the machine tool body 1. The transmitter connecting plate 65 is fixedly connected to the transmitter bracket 67 via the n-shaped support 66. The X-axis long displacement linear slide 64 is disposed on the transmitter connecting plate 65 along the X-axis direction. The Z-axis long displacement linear slide 63 is disposed on the slider of the X-axis long displacement linear slide 64 along the Z-axis direction. The vertical end of the transmitter connecting L-plate 62 is fixedly connected to the slider of the Z-axis long displacement linear slide 63. The interferometer transmitter 61 is fixedly connected to the horizontal end of the transmitter connecting L-plate 62.

[0071] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment 1.

[0072] The X-axis long displacement linear slide 64 can achieve a position adjustment of 150mm in the X-axis direction, and the vertically placed Z-axis long displacement linear slide 63 can achieve a position adjustment of 150mm in the Z-axis direction.

[0073] Specific Implementation Method Nine: Combining Figures 1 to 12 This embodiment describes a receiving module 5 comprising an interferometer receiver 51, a receiving module connecting plate 52, a pitch rotation module 53, a yaw rotation module 54, a receiving T-shaped connecting plate 55, and a receiving Z-axis micro-displacement stage 56. The receiving Z-axis micro-displacement stage 56 is fixedly mounted on the worktable of the machine tool body 1. The horizontal end of the receiving T-shaped connecting plate 55 is fixedly mounted on the moving block of the receiving Z-axis micro-displacement stage 56. The inner end of the receiving module connecting plate 52 is connected to the vertical end of the receiving T-shaped connecting plate 55 sequentially via the pitch rotation module 53 and the yaw rotation module 54. The interferometer receiver 51 is fixedly mounted on the outer end of the receiving module connecting plate 52.

[0074] The undisclosed technical features in this embodiment are the same as those in Specific Embodiment 1.

[0075] The interferometer used in this invention is a Renishaw interferometer, which is used to measure the different errors generated by the machine tool under force loading.

[0076] The pitch rotation module 53 and the yaw rotation module 54 can adjust the angle in the pitch and yaw directions, while other fine adjustments are made by the adjustment methods built into the measuring instrument.

[0077] Specific Implementation Method Ten: Combining Figures 1 to 12 This embodiment describes a measurement method based on a force-induced error measuring device, which includes the following steps:

[0078] Step 1, Pre-adjustment: Before starting the measurement, install the receiver module 5 and the transmitter module 6 on the worktable and bed of the machine tool body 1 respectively, and adjust the position and orientation of the interferometer receiver 51 and the interferometer transmitter 61 to ensure good optical path; the force loading device 3 adjusts the moving distance of the electric cylinder 33 to fix the constant Y-axis force applied to the L-shaped aluminum plate 41, and adjusts the torque around the Y-axis and around the Z-axis by adjusting the X-axis linear module 37 and the Z-axis displacement plate 35; the six-dimensional force sensor 42 senses the force and torque in real time;

[0079] Step 2, Measurement Stage: The machining area is set to 100mm × 100mm. Measurement points are taken every 10mm along the X and Y axes of the machine tool, generating a total of 10 × 10 = 100 fixed measurement points. When the machine tool is subjected to a force in the Y direction, the transmitter module 6 and receiver module 5 are installed on the front of the machine tool. The X and Y axes of the machine tool are moved until they stop at X=0mm and Y=0mm, respectively. The force loading device 3 is controlled to apply the magnitude and position of the X-axis force. This will generate an X-axis force and torques around the Z and X axes. Different force and torque parameters can be obtained through the six-dimensional force sensor 42. These parameters are applied during and after the movement. The force applied by the force loading device 3 remains constant; by controlling the X-axis movement, the machine tool moves sequentially to ten fixed measurement points [0mm, 0mm~100mm]. During the 5-second pause at each fixed measurement point, the force and torque parameters are recorded by the six-dimensional force sensor 42, and the force error is measured and recorded by the interferometer to obtain the force error parameters in [0mm, 0mm~100mm]. When this set of force error measurements is completed, the force and torque parameters can be changed by altering the displacement of the electric cylinder 33 and the connection of the Z-axis displacement plate 35, and by moving the X-axis linear module 37, so as to uniformly measure the force error parameters under multiple sets of force and torque parameters.

[0080] When the X=0mm data measurement is completed, move the X-axis to move the machine tool to X=10mm. At this time, the receiver module 5 moves to X=10mm along the X-axis. Move the X-direction long displacement linear slide 64 of the transmitter module 6 to align the interferometer receiver 51 and the interferometer transmitter 61. If the optical path is not good at this time, the pose of the receiver module 5 and the transmitter module 6 can be adjusted. Continue to measure the force-induced error parameters of ten points on [10mm, 0mm~100mm] according to the above method. Through this method, ten sets of force-induced error parameters caused by Y-direction force from 0mm to 100mm are obtained in sequence.

[0081] After measuring the force-induced error parameters caused by the Y-axis force, rotate the L-shaped aluminum plate 41 90 degrees and fix it. Adjust the position of the force loading device 3 so that it applies an X-axis force to the machine tool. Move the Y-axis and repeat the above steps to obtain the error data after the X-axis force is applied.

[0082] The measurement method of the present invention has the following advantages:

[0083] 1. Solved the problem of measuring force-induced errors, and realized the error measurement of various forces and torques;

[0084] 2. Simplify the error measurement steps and improve the efficiency of error measurement.

[0085] The foregoing has shown and described the basic principles, main features, and advantages of the present invention. Those skilled in the art should understand that the present invention is not limited to the above embodiments. The embodiments and descriptions in the specification are merely illustrative of the principles of the invention. Various changes and modifications can be made to the invention without departing from its spirit and scope, and all such changes and modifications fall within the scope of the present invention as claimed. The scope of protection of this invention is defined by the appended claims and their equivalents.

Claims

1. A force-induced error measuring device, characterized in that: The machine tool includes a main body (1), a fixed frame (2), a force loading device (3), a force measuring device (4), a receiver module (5), and a transmitter module (6). The force measuring device (4) is fixed to the worktable of the main body (1). The fixed frame (2) is vertically fixed to the bed of the main body (1) along the Y-axis. The force loading device (3) is set on the fixed frame (2). The loading end of the force loading device (3) is set towards the force measuring device (4) and applies force along the Y-axis. The loading end of the force loading device (3) can move along the X-axis, Y-axis, and Z-axis respectively. The transmitter module (6) is fixed to the bed of the main body (1), and the receiver module (5) is fixed to the worktable of the main body (1).

2. The force-induced error measuring device according to claim 1, characterized in that: The fixed frame (2) is an aluminum profile frame, and the force loading device (3) can move along the Y-axis on the fixed frame (2).

3. The force-induced error measuring device according to claim 2, characterized in that: The force loading device (3) includes an X-axis linear motion component, a Z-axis linear motion component and a force loading component. The X-axis linear motion component is set on the fixed frame (2). The force loading component is connected to the execution end of the X-axis linear motion component through the Z-axis linear motion component. The force loading component is set along the Y-axis direction.

4. The force-induced error measuring device according to claim 3, characterized in that: The force loading assembly includes a bullseye wheel (31), a spring (32), an electric cylinder (33), and two arc guide plates (34). The electric cylinder (33) is fixed to the execution end of the Z-axis linear motion assembly. The two arc guide plates (34) are fixedly connected to each other to form a cylindrical sleeve. The cylindrical sleeve is fitted on the outside of the execution end of the electric cylinder (33) rod. The bullseye wheel (31) is located at the front end inside the cylindrical sleeve. The spring (32) is located inside the cylindrical sleeve. The bullseye wheel (31) is connected to the execution end of the electric cylinder (33) rod through the spring (32).

5. The force-induced error measuring device according to claim 3, characterized in that: The Z-axis linear motion assembly includes a Z-axis displacement plate (35) and a Z-axis fixing plate (36). The Z-axis fixing plate (36) is vertically fixed to the execution end of the X-axis linear motion assembly. The Z-axis displacement plate (35) is the execution end of the Z-axis linear motion assembly. Multiple sets of connecting holes (361) are evenly distributed along the vertical direction on the Z-axis fixing plate (36). Multiple sets of through holes (351) are evenly distributed along the vertical direction on the Z-axis displacement plate (35). The through holes (351) and the connecting holes (361) are correspondingly set and connected by connecting bolts. The connection between different through holes (351) and the connecting holes (361) realizes the adjustment of the Z-axis displacement plate (35) along the Z-axis direction.

6. The force-induced error measuring device according to claim 3, characterized in that: The X-axis linear motion assembly includes an X-axis linear module (37) and two L-shaped fixing plates (38). The two L-shaped fixing plates (38) are arranged opposite to each other. The vertical ends of the L-shaped fixing plates (38) are fixed to the fixed frame (2) by tightening bolts. The X-axis linear module (37) is fixed to the horizontal ends of the two L-shaped fixing plates (38). The slide of the X-axis linear module (37) is the execution end of the X-axis linear motion assembly.

7. The force-induced error measuring device according to claim 1, characterized in that: The force measuring device (4) includes an L-shaped aluminum plate (41), a six-dimensional force sensor (42), and a horizontal platform (43). The horizontal platform (43) is fixed on the worktable of the machine tool body (1). The six-dimensional force sensor (42) is set on the horizontal platform (43). The horizontal end of the L-shaped aluminum plate (41) is connected to the six-dimensional force sensor (42). The opening of the L-shaped aluminum plate (41) is set towards the force loading device (3).

8. The force-induced error measuring device according to claim 1, characterized in that: The transmitter module (6) includes an interferometer transmitter (61), a transmitter connecting L plate (62), a Z-axis long displacement linear slide (63), an X-axis long displacement linear slide (64), a transmitter connecting plate (65), an n-shaped support (66), and a transmitter bracket (67). The transmitter bracket (67) is fixed to the bed of the machine tool body (1). The transmitter connecting plate (65) is fixed to the transmitter bracket (67) through the n-shaped support (66). The X-axis long displacement linear slide (64) is set on the transmitter connecting plate (65) along the X-axis direction. The Z-axis long displacement linear slide (63) is set on the slider of the X-axis long displacement linear slide (64) along the Z-axis direction. The vertical end of the transmitter connecting L plate (62) is fixed to the slider of the Z-axis long displacement linear slide (63). The interferometer transmitter (61) is fixed to the horizontal end of the transmitter connecting L plate (62).

9. The force-induced error measuring device according to claim 1, characterized in that: The receiver module (5) includes an interferometer receiver (51), a receiver connecting plate (52), a pitch rotation module (53), a yaw rotation module (54), a receiver T-shaped connecting plate (55), and a receiver Z-axis micro-displacement stage (56). The receiver Z-axis micro-displacement stage (56) is fixedly connected to the worktable of the machine tool body (1). The horizontal end of the receiver T-shaped connecting plate (55) is fixedly connected to the moving block of the receiver Z-axis micro-displacement stage (56). The inner end of the receiver connecting plate (52) is connected to the vertical end of the receiver T-shaped connecting plate (55) in sequence through the pitch rotation module (53) and the yaw rotation module (54). The interferometer receiver (51) is fixedly connected to the outer end of the receiver connecting plate (52).

10. A measurement method based on the force-induced error measuring device according to any one of claims 1 to 9, characterized in that: Includes the following steps: Step 1, Pre-adjustment: Before starting the measurement, the receiving module (5) and the transmitting module (6) are installed on the worktable and bed of the machine tool body (1) respectively, and the positions of the interferometer receiving end (51) and the interferometer transmitting end (61) are adjusted to ensure good optical path; the force loading device (3) adjusts the moving distance of the electric cylinder (33) to fix the constant Y-axis force applied to the L-shaped aluminum plate (41), and adjusts the torque around the Y-axis and around the Z-axis by adjusting the X-axis linear module (37) and the Z-axis displacement plate (35); the six-dimensional force sensor (42) senses the force and torque in real time; Step 2, Measurement Stage: Set the processing area to a 100mm×100mm area, and take a measurement point every 10mm in the X-axis and Y-axis directions of the machine tool, generating a total of 10×10=100 fixed measurement points; When the measuring machine tool is subjected to a force in the Y-axis, install the transmitter module (6) and receiver module (5) in the forward direction of the machine tool, move the X-axis and Y-axis of the machine tool to stop at X=0mm and Y=0mm, and control the force loading device (3) to load the magnitude and position of the X-axis force. At this time, the X-axis force and the torque around the Z-axis and X-axis will be generated. Different force and torque parameters can be obtained through the six-dimensional force sensor (42). When the movement is in progress and when it stops, the force The loading force of the loading device (3) remains constant; by controlling the X-axis movement, the machine tool moves sequentially to ten fixed measurement points [0mm, 0mm~100mm]. During the 5-second stay at each fixed measurement point, the force and torque parameters at this time are recorded by the six-dimensional force sensor (42), and the force error at this time is recorded by the interferometer to obtain the force error parameters on [0mm, 0mm~100mm]. When this set of force error measurements is completed, the force and torque parameters can be changed by changing the displacement of the electric cylinder (33) and the connection of the Z-axis displacement plate (35) and moving the X-axis linear module (37), and the force error parameters under multiple sets of force and torque parameters can be measured uniformly. When the X=0mm data measurement is completed, move the X-axis to move the machine tool to X=10mm. At this time, the receiving module (5) moves to X=10mm along the X-axis. Move the X-direction long displacement linear slide (64) of the transmitting module (6) to align the interferometer receiving end (51) and the interferometer transmitting end (61). If the optical path is not good, the position of the receiving module (5) and the moving transmitting module (6) can be adjusted. Continue to measure the force error parameters of ten points on [10mm, 0mm~100mm] according to the above method. Through this method, the force error parameters caused by the Y-direction force from 0mm to 100mm are obtained in sequence. After measuring the force-induced error parameters caused by the Y-axis force, rotate the L-shaped aluminum plate (41) 90 degrees and fix it. Adjust the position of the force loading device (3) so that it can apply the X-axis force to the machine tool. Move the Y-axis and repeat the above steps to obtain the error data after the X-axis force is applied.

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