Machine tool spindle dynamic error measuring device and machine tool spindle dynamic error measuring method

Abstract

The invention discloses a machine tool spindle dynamic error measuring device and a machine tool spindle dynamic error measuring method. The machine tool spindle dynamic error measuring device comprises a cutter mirror, a laser transmitter and a laser receiver, the cutter mirror comprises a prism reflection head and a mirror handle, one end of the mirror handle is connected with the prism reflection head, the other end of the mirror handle is used for being connected with a machine tool spindle, the prism reflection head comprises a plurality of reflection planes, and the reflection planes are arranged in the circumferential direction of the prism reflection head. When the machine tool spindle drives the cutter mirror to rotate, the reflecting planes sequentially reflect laser beams emitted by the laser emitter to the laser receiver. According to the dynamic error measuring device and method for the machine tool spindle, dynamic error measurement can be carried out in the normal operation process of the machine tool, dynamic errors caused by high-speed rotation, temperature change, vibration and other factors in the actual working process of the machine tool are monitored, error information obtained through measurement is more accurate, and the measuring accuracy is improved. And the structure is simple and easy to realize.

Description

TECHNICAL FIELD

[0001] The present application relates to the field of precision measurement, and in particular to a machine tool spindle dynamic error measurement device and a machine tool spindle dynamic error measurement method. BACKGROUND

[0002] In modern manufacturing industry, machine tools are important processing equipment, and their precision directly affects the quality of workpieces and production efficiency. In order to ensure the high-precision operation of machine tools, regular detection and calibration are essential.

[0003] However, most of the existing machine tool detection methods are carried out under static conditions, that is, error measurement is performed on the spindle or other key components under the condition that the machine tool is stopped, wherein the static detection can only provide error information of the machine tool in the static state, and ignores the dynamic error caused by high-speed rotation, temperature change, vibration and other factors in the actual working process of the machine tool, so that the measured error information is inaccurate, which may further cause problems such as size deviation and surface quality degradation of the processed parts. SUMMARY

[0004] The present application provides a machine tool spindle dynamic error measurement device and a machine tool spindle dynamic error measurement method to realize error measurement of machine tools during processing and solve the problem of inaccurate error measurement results.

[0005] According to an aspect of the present application, a machine tool spindle dynamic error measurement device is provided, comprising a tool mirror, a laser emitter and a laser receiver.

[0006] The tool mirror comprises a prism reflection head and a mirror handle, one end of the mirror handle is connected with the prism reflection head, and the other end of the mirror handle is used to connect the machine tool spindle.

[0007] The laser emitter is used to emit a laser beam to the prism reflection head.

[0008] The laser receiver is used to receive the laser beam reflected by the prism reflection head.

[0009] The prism reflection head comprises a plurality of reflection planes, and the plurality of reflection planes are arranged along the circumference of the prism reflection head.

[0010] When the machine tool spindle drives the tool mirror to rotate, each reflection plane reflects the laser beam emitted by the laser emitter to the laser receiver in turn.

[0011] Optionally, each reflection plane is parallel to the center line of the machine tool spindle.

[0012] Optionally, the plurality of reflection planes are uniformly arranged along the circumference of the prism reflection head.

[0013] Optionally, the number of the reflection planes in the prism reflection head is greater than or equal to 3.

[0014] Optionally, the prism reflection head and the mirror handle of the knife mirror are an integral structure.

[0015] Optionally, the center line of the machine tool spindle is located in the spatial plane formed by the laser emitter, the laser receiver and the knife mirror.

[0016] Optionally, the diameter of the prism reflection head is greater than, equal to or smaller than the diameter of the mirror handle.

[0017] According to another aspect of the present application, a machine tool spindle dynamic error measurement method is provided for any machine tool spindle dynamic error measurement device of the first aspect;

[0018] The machine tool spindle dynamic error measurement method comprises:

[0019] mounting the knife mirror on the machine tool spindle;

[0020] starting the machine tool to drive the machine tool spindle to rotate the knife mirror;

[0021] emitting a laser beam from the laser emitter to the prism reflection head of the knife mirror;

[0022] receiving the laser beam reflected by the prism reflection head through the laser receiver;

[0023] determining the distance between each reflection plane of the prism reflection head and the laser emitter through triangulation based on the received laser beam;

[0024] determining the error of the machine tool spindle when rotating based on the distance between each reflection plane of the prism reflection head and the laser emitter.

[0025] Optionally, before mounting the knife mirror on the machine tool spindle, the method further comprises:

[0026] determining the diameter of the mirror handle of the knife mirror based on the rotational speed of the machine tool spindle, wherein the greater the rotational speed of the machine tool spindle, the smaller the diameter of the mirror handle of the knife mirror.

[0027] Optionally, before mounting the knife mirror on the machine tool spindle, the method further comprises:

[0028] determining the number of the reflection planes in the prism reflection head based on the target error measurement accuracy, wherein the higher the target error measurement accuracy, the greater the number of the reflection planes in the prism reflection head.

[0029] The machine tool spindle dynamic error measurement device and the machine tool spindle dynamic error measurement method provided by the embodiment of the present application can measure dynamic error in the normal operation process of the machine tool, realize monitoring of dynamic error caused by high-speed rotation, temperature change, vibration and other factors in the actual working process of the machine tool, make the measured error information more accurate, and have simple structure and easy realization.

[0030] It should be understood that the content described in this part is not intended to identify key or important features of the embodiments of the present application, nor to limit the scope of the present application. Other features of the present application will become apparent from the following description. BRIEF DESCRIPTION OF DRAWINGS

[0031] In order to more clearly illustrate the technical solutions in the embodiments of the present application, the drawings needed in the embodiment description will be briefly introduced. Obviously, the drawings in the following description are only some embodiments of the present application, and other drawings can be obtained by those skilled in the art without creative labor.

[0032] Figure 1 A structural schematic diagram of a machine tool spindle dynamic error measurement device provided by the embodiment of the present application is shown in the figure.

[0033] Figure 2 A structural schematic diagram of a machine tool spindle dynamic error measurement device provided by the embodiment of the present application is shown in the figure. Figure 1 An enlarged structural schematic diagram at A is shown in the figure.

[0034] Figure 3 A structural schematic diagram of a tool mirror provided by the embodiment of the present application is shown in the figure.

[0035] Figure 4 A structural schematic diagram of another tool mirror provided by the embodiment of the present application is shown in the figure.

[0036] Figure 5 A flowchart of a machine tool spindle dynamic error measurement method provided by the embodiment of the present application is shown in the figure.

[0037] Figure 6 A flowchart of another machine tool spindle dynamic error measurement method provided by the embodiment of the present application is shown in the figure.

[0038] Figure 7 A flowchart of another machine tool spindle dynamic error measurement method provided by the embodiment of the present application is shown in the figure. DETAILED DESCRIPTION

[0039] In the following, the technical solutions in the embodiments of the present application will be described clearly and completely in conjunction with the drawings in the embodiments of the present application, so that those skilled in the art can better understand the present application. Obviously, the described embodiments are only a part of the embodiments of the present application, rather than all the embodiments. Based on the embodiments in the present application, all other embodiments obtained by those skilled in the art without creative work should fall within the scope of protection of the present application.

[0040] It should be noted that the terms "first", "second" and the like in the description and claims of the present application and the above drawings are used to distinguish similar objects, and do not necessarily indicate a specific order or a chronological sequence. It should be understood that the data thus used can be interchanged under appropriate circumstances, so that the embodiments of the present application described herein can be implemented in an order other than that illustrated or described herein. In addition, the terms "include" and "have" and any variations thereof are intended to cover non-exclusive inclusion, for example, a process, method, system, product or device including a series of steps or units need not be limited to those steps or units clearly listed, but can include other steps or units not clearly listed or inherent to these processes, methods, products or devices.

[0041] Figure 1 A structural schematic diagram of a machine tool spindle dynamic error measurement device provided by an embodiment of the present application, Figure 2 A structural schematic diagram of a machine tool spindle dynamic error measurement device provided by an embodiment of the present application, Figure 1 An enlarged structural schematic diagram at A, Figure 3 A structural schematic diagram of a tool mirror provided by an embodiment of the present application, Figure 4 A structural schematic diagram of another tool mirror provided by an embodiment of the present application, as Figures 1-4 As shown in the drawings, the machine tool spindle dynamic error measurement device provided by the embodiment of the present application includes a tool mirror 10, a laser emitter 11 and a laser receiver 12. The tool mirror 10 includes a prism reflection head 101 and a mirror handle 102. One end of the mirror handle 102 is connected with the prism reflection head 101, and the other end of the mirror handle 102 is used to connect with a machine tool spindle 20. The laser emitter 11 is used to emit a laser beam 30 to the prism reflection head 101, and the laser receiver 12 is used to receive the laser beam 30 reflected by the prism reflection head 101. The prism reflection head 101 includes a plurality of reflection planes 40, which are arranged along the circumference of the prism reflection head 101. When the machine tool spindle 20 drives the tool mirror 10 to rotate, each reflection plane 40 reflects the laser beam 30 emitted by the laser emitter 11 to the laser receiver 12 in turn.

[0042] Specifically, the machine tool spindle 20 refers to a core component in a machine tool for mounting a tool and driving the tool to rotate for cutting and other machining steps. The machine tool spindle 20 is usually driven by a motor and rotates at high speed through a series of transmission mechanisms (such as belts, gears, etc.).

[0043] When the machine tool receives the machining instructions, the spindle motor starts to work and drives the machine tool spindle 20 to rotate through the transmission mechanism. The machine tool spindle 20 rotates at a set speed, driving the cutter installed thereon to perform cutting and other machining steps. Different machining tasks can set different rotation speeds and feed speeds.

[0044] In actual use, the machine tool spindle 20 may have center offset error and tool head swing error, wherein the center offset error refers to the deviation between the actual rotation center and the ideal rotation center of the machine tool spindle 20 when it rotates; the tool head swing error refers to the swing error of the tool head relative to the ideal rotation track when the tool rotates under the drive of the machine tool spindle 20, due to the radial runout or swing of the machine tool spindle 20 during rotation. These errors will directly affect the machining quality and efficiency.

[0045] In order to effectively reduce the influence of center offset error and tool head swing error on machining quality, the related art uses a static detection method to measure the error, that is, the error of the machine tool spindle 20 is measured in the machine tool stopped state. However, static detection can only provide error information of the machine tool in the static state, and cannot accurately capture the error condition of the machine tool spindle 20 in the actual working state, so that the measured error information is inaccurate.

[0046] Based on the above technical problems, the embodiment of the present application provides a machine tool spindle dynamic error measurement device, as shown in Figures 1-4 The machine tool spindle dynamic error measurement device includes a tool mirror 10, which is designed similarly to a conventional tool, with the main difference being that the front-end cutting tool is replaced by a prism reflection head 101. This design makes the installation process of the tool mirror 10 very simple, similar to the installation method of a conventional tool.

[0047] Specifically, as shown in Figures 1-4 The mirror handle 102 of the tool mirror 10 can be a cylindrical rod, and its diameter can be selected according to the speed requirement of the machine tool spindle 20 (e.g. Ф6.0mm, Ф4.0mm, Ф3.0mm, Ф1.8mm, etc.).

[0048] One end of the mirror handle 102 can be inserted into the hole of the standard tool interface of the machine tool spindle 20 and fixed by the chuck locking mechanism of the standard tool interface, wherein the chuck locking mechanism can be composed of a plurality of adjustable claws. When the chuck locking mechanism is tightened, the plurality of claws will contract inward and tightly clamp the mirror handle 102, ensuring that it is firmly fixed on the machine tool spindle 20. This installation method is the same as that of a conventional tool, and is simple to operate, so that tool mirrors 10 of different sizes and shapes can be quickly replaced as needed, facilitating maintenance and adjustment.

[0049] Further, the other end of the mirror handle 102 is provided with a prism reflection head 101, which is in the shape of a prism, i.e., has a polygonal cross section, and along the axial direction, the polygonal surface at one end of the prism reflection head 101 is fixedly connected to the mirror handle 102, and each side surface of the prism reflection head 101 is provided as a reflection plane 40, at this time, each reflection plane 40 is distributed in a circumferential direction around the central axis of the prism reflection head 101.

[0050] The machine tool spindle dynamic error measurement device further comprises a laser emitter 11 and a laser receiver 12, which are fixedly arranged, the laser emitter 11 is used to continuously or periodically emit a laser beam 30, which can be a beam of visible or invisible light with fixed wavelength and directivity (for example, red light or infrared light), for irradiating the prism reflection head 101.

[0051] After the tool mirror 10 is installed on the machine tool spindle 20, the machine tool spindle 20 can drive the tool mirror 10 to rotate at high speed, wherein each reflection plane 40 on the prism reflection head 101 will periodically enter the path of the laser beam 30 during the rotation of the tool mirror 10, when a certain reflection plane 40 rotates to a position perpendicular to the direction of the path of the laser beam 30, the laser beam 30 will be reflected by the reflection plane 40 to the laser receiver 12.

[0052] The laser receiver 12 is an optoelectronic detection module, which receives the laser beam 30 reflected by the reflection plane 40 and converts it into an electrical signal for subsequent processing.

[0053] Among them, based on the laser beam 30 received by the laser receiver 12, the actual spatial position of the reflection plane 40 reflecting the laser beam 30 can be calculated by using an algorithm.

[0054] As the machine tool spindle 20 continues to rotate, each reflection plane 40 of the prism reflection head 101 reflects the laser beam 30 in turn to participate in measurement, so that during one rotation of the machine tool spindle 20, the laser receiver 12 can receive multiple laser beams 30 to collect measurement data of multiple reflection planes 40, which can reflect the displacement error of the machine tool spindle 20 at different angles.

[0055] Further, based on the measurement data of the above-mentioned multiple reflection planes 40, the center offset error and tool head swing error of the machine tool spindle 20 during rotation and other dynamic error data can be obtained by using a spindle error analysis algorithm.

[0056] In summary, the machine tool spindle dynamic error measurement device provided by the embodiment of the present application can perform dynamic error measurement during normal operation of the machine tool, realize monitoring of dynamic errors caused by high-speed rotation, temperature change, vibration and other factors during actual work of the machine tool, and make the measured error information more accurate. Further based on the measured dynamic error, the machine tool error compensation algorithm can be used to adjust the feed parameters or tool path of the machine tool, so as to realize dynamic correction and error compensation of the tool movement track, ensure the machining precision of the workpiece, and the structure is simple and easy to implement.

[0057] With reference to the foregoing Figures 1-4 Optionally, each reflection plane 40 is parallel to the center line of the machine tool spindle 20.

[0058] The center line of the machine tool spindle 20 refers to a geometric symmetry axis around which the machine tool spindle 20 rotates in an ideal state.

[0059] In this embodiment, when the tool mirror 10 is installed on the machine tool spindle 20, each reflection plane 40 on the prism reflection head 101 is parallel to the center line of the machine tool spindle 20, and at this time, the normal direction of the reflection plane 40 is perpendicular to the extension direction of the center line of the machine tool spindle 20. It can be understood that if the machine tool spindle 20 is regarded as a vertical rotating shaft, each reflection plane 40 is a vertically extending plane. Each reflection plane 40 always remains parallel to the center line of the machine tool spindle 20 during rotation of the tool mirror 10 and does not tilt or distort.

[0060] Since each reflection plane 40 is parallel to the center line of the machine tool spindle 20, the light path of each reflection plane 40 reflecting the laser beam 30 has high consistency, which facilitates the laser receiver 12 to accurately capture the laser beam 30 reflected by the reflection plane 40. At the same time, stable light path helps to improve the accuracy of the algorithm, reduce error sources, and make the measured error information more accurate.

[0061] With reference to the foregoing Figures 1-4 Optionally, the plurality of reflection planes 40 are uniformly arranged along the circumference of the prism reflection head 101.

[0062] The plurality of reflection planes 40 are equally spaced along the circumferential direction of the prism reflection head 101, and the included angle between adjacent reflection planes 40 is equal. Since the reflection planes 40 are uniformly distributed, when the machine tool spindle 20 drives the tool mirror 10 to rotate, it can ensure that the laser beam 30 can be reflected to the laser receiver 12 at the same interval during rotation of the machine tool spindle 20, that is, the time interval between each time the laser receiver 12 receives the laser beam 30 is consistent. This is conducive to identifying whether the machine tool spindle 20 error has a periodicity (such as periodic runout caused by bearing wear), and facilitates subsequent error compensation through the algorithm.

[0063] It should be noted that, compared with the curved structure, the planar structure of the reflection plane 40 is easier to process and detect, can ensure the surface flatness and reflection consistency of the prism reflection head 101, and reduce the manufacturing cost.

[0064] With reference to the foregoing Figures 1-4 Optionally, the number of the reflection planes 40 in the prism reflection head 101 is greater than or equal to 3.

[0065] As described above, the prism reflection head 101 is in the shape of a prism, and each side of the prism reflection head 101 can be provided as a reflection plane 40.

[0066] In the embodiment, when each reflection plane 40 enters the light path of the laser beam 30 during the rotation of the machine tool spindle 20, the laser beam 30 reflected by the reflection plane 40 to the laser receiver 12 can generate an effective laser reflection signal, thereby corresponding to an independent position measurement, that is, each reflection plane 40 can be regarded as an independent measurement point. By providing the prism reflection head 101 with at least 3 reflection planes 40, a plurality of measurement points can be collected within one rotation of the machine tool spindle 20, so as to obtain sufficient measurement point data to accurately reflect the dynamic behavior of the machine tool spindle 20 and improve the accuracy of dynamic error measurement.

[0067] The shape of the prism reflection head 101 can include a triangular prism, a quadrangular prism, a pentagonal prism, a hexagonal prism, or an octagonal prism, and the number of the reflection planes 40 in the prism reflection head 101 can correspond to 3, 4, 5, 6, or 8, but is not limited thereto.

[0068] It can be understood that the more the number of the reflection planes 40 of the prism reflection head 101, the more the measurement point data collected within one rotation of the machine tool spindle 20, and the more accurate the error analysis result. Therefore, the prism reflection head 101 with different numbers of reflection planes 40 can be selected to adapt to different application scenarios and precision requirements.

[0069] With reference to the foregoing Figures 1-4 Optionally, the prism reflection head 101 and the mirror handle 102 of the tool mirror 10 are in an integrated structure.

[0070] Specifically, in the embodiment, the prism reflection head 101 and the mirror handle 102 are not connected together by assembly, but are formed as a whole by manufacturing process, that is, an integrated structure, which can be divided into the prism reflection head 101 and the mirror handle 102 according to regions.

[0071] Wherein, since the prism reflecting head 101 and the mirror handle 102 of the knife mirror 10 are integrally formed structure, there is no gap or misalignment between the prism reflecting head 101 and the mirror handle 102, which can ensure the geometric symmetry and stability of the whole knife mirror 10. At the same time, it can also avoid the error caused by improper assembly, ensure the position and angle of each reflecting plane 40 accurate and faultless, and be beneficial to improve the accuracy of error measurement.

[0072] And the integrated structure of the knife mirror 10 has higher mechanical strength and rigidity than the split structure, which can keep stable at high speed and is not easy to deform. At the same time, the integrated structure reduces the potential loose point, which can reduce the signal fluctuation caused by vibration and ensure the consistency and reliability of the measurement data.

[0073] Optionally, the knife mirror 10 can be formed by using precision casting, CNC machining and other manufacturing processes to ensure the seamless connection between the prism reflecting head 101 and the mirror handle 102.

[0074] The material of the knife mirror 10 can be high-strength and wear-resistant materials such as steel and copper, but is not limited thereto.

[0075] Further, the side surface of the prism reflecting head 101 can be polished, coated and treated, so as to form the reflecting plane 40 on the side surface of the prism reflecting head 101. In this way, the reflecting plane 40 can form a full reflecting plane with a laser reflectivity close to 100%, which ensures that the laser receiver 12 can stably receive a stronger laser beam 30.

[0076] Wherein, the coating process can use aluminum (Al) as the coating material to form a mirror surface with high reflectivity, but is not limited thereto.

[0077] Continuing to refer to Figure 1 Optionally, the center line of the machine tool spindle 20 is located in the space plane formed by the laser emitter 11, the laser receiver 12 and the knife mirror 10.

[0078] Specifically, the laser emitter 11 and the laser receiver 12 can be installed on the machine tool bed or the independent support 50 and kept relatively static.

[0079] In the three-dimensional space, the positional relationship of the laser transmitter 11, the laser receiver 12 and the tool mirror 10 can define a spatial plane in which the center line of the machine tool spindle 20 is located. In this way, during the high-speed rotation of the tool mirror 10 driven by the machine tool spindle 20, the laser beam 30 emitted by the laser transmitter 11 will be incident on each reflection plane 40 of the prism reflection head 101 at a fixed angle, and at the same time, each reflection plane 40 of the prism reflection head 101 will reflect the laser beam 30 to the laser receiver 12 at a fixed angle. At this time, it is convenient to use the triangulation method to obtain the actual spatial position of each reflection plane 40, and at the same time, it can be ensured that the reflection path of the laser beam 30 changes in the same plane each time, avoiding complex light path deflection in three-dimensional space. The change of the light path of the laser beam 30 can more intuitively reflect the actual motion state and spindle deviation state of the machine tool spindle 20, reduce the source of measurement error, facilitate the establishment of a unified coordinate system and mathematical model for error analysis, and help improve the accuracy of error measurement data.

[0080] In addition, the planar layout is easier to ensure the installation accuracy of the machine tool spindle dynamic error measurement device, reduces the assembly difficulty, and helps to quickly complete the installation and calibration of the machine tool spindle dynamic error measurement device, reduces the debugging time and cost.

[0081] It should be noted that the relative position difference between the laser transmitter 11 and the laser receiver 12 is an important geometric parameter that affects the incidence angle and reception efficiency of the laser beam 30. The distance between the laser transmitter 11 and the laser receiver 12 can be adjusted according to the model of the laser transmitter 11 and the laser receiver 12 and the actual distance between the laser transmitter 11 and the laser receiver 12 and the prism reflection head 101 during measurement, in order to achieve the best measurement accuracy. The present embodiment does not make specific limitations.

[0082] Optionally, the diameter of the prism reflection head 101 is greater than, equal to, or less than the diameter of the mirror handle 102.

[0083] The diameter of the prism reflection head 101 refers to the maximum circumscribed circle diameter of the prism reflection head 101 in the cross section. For example, when the prism reflection head 101 is a polygonal prism (such as a hexagonal prism), its diameter is measured by the diagonal distance of its polygonal face.

[0084] The diameter of the mirror handle 102 refers to the maximum circumscribed circle diameter of the mirror handle 102 in the cross section. For example, when the mirror handle 102 is a cylinder, its diameter is the diameter of the circular cross section.

[0085] In the embodiment, the diameter of the prism reflection head 101 is not less than the diameter of the mirror handle 102, so that each reflection plane 40 of the prism reflection head 101 can have a larger area, which is beneficial to improve the coverage of the laser beam 30 and enhance the stability of the laser beam 30.

[0086] Meanwhile, the smaller the diameter of the prism reflection head 101, the fewer the number of the largest reflection planes 40 that can be actually processed; the larger the diameter of the prism reflection head 101, the more the number of the largest reflection planes 40 that can be actually processed. In the embodiment, the larger prism reflection head 101 can accommodate more reflection planes 40, thereby facilitating to increase the number of measurement points collected by the machine tool spindle 20 in one rotation, and improving the error measurement accuracy.

[0087] Optionally, the diameter of the mirror handle 102 is not greater than the diameter of the prism reflection head 101, which can reduce the centrifugal force of the tool mirror 10 when rotating at high speed, improve the dynamic stability of the tool mirror 10, prevent vibration from interfering with the error measurement accuracy, and improve the accuracy of dynamic error measurement.

[0088] In other embodiments, the diameter of the prism reflection head 101 can be less than the diameter of the mirror handle 102 to further reduce the centrifugal force of the tool mirror 10 when rotating at high speed, improve the dynamic stability of the tool mirror 10, prevent vibration from interfering with the error measurement accuracy, and improve the accuracy of dynamic error measurement, under the condition of meeting the measurement accuracy requirement.

[0089] It should be noted that the structural parameters of the tool mirror 10 (including the diameter of the mirror handle 102 and the number of reflection planes 40) can be set based on the specific requirements of the measurement task. For example, the number of reflection planes 40 that the prism reflection head should have is determined according to the required minimum data acquisition amount, and the size of the mirror handle 102 is reasonably selected in combination with the highest and lowest speed range of the machine tool spindle, so as to ensure that the tool mirror can work stably and meet the measurement accuracy requirement under different working conditions. For example, a small-diameter mirror handle 102 and fewer reflection planes 40 are preferred when the machine tool spindle rotates at high speed to reduce the influence of centrifugal force; a larger-diameter mirror handle 102 and more reflection planes 40 are selected when the machine tool spindle rotates at low speed to improve the sampling density and error measurement accuracy, but not limited thereto.

[0090] In addition, under the premise of meeting the measurement accuracy, the best number of reflection planes 40 can be selected by considering the manufacturability, thereby reducing the manufacturing difficulty of the tool mirror 10.

[0091] Based on the same inventive concept, the embodiment of the present application also provides a machine tool spindle dynamic error measurement method for the machine tool spindle dynamic error measurement device of any embodiment of the present application, so that the machine tool spindle dynamic error measurement method provided by the embodiment of the present application has the technical effects of the technical solutions in any of the above embodiments, and the same or corresponding structures and explanations of terms are not repeated here.

[0092] Figure 5 A flowchart of a machine tool spindle dynamic error measurement method provided by an embodiment of the present application is shown in Figure 5 The machine tool spindle dynamic error measurement method comprises the following steps.

[0093] S11, mounting the tool mirror on the machine tool spindle.

[0094] The tool mirror is mounted on the machine tool spindle and is coaxial with the center line of the machine tool spindle.

[0095] S12, starting the machine tool to drive the tool mirror to rotate.

[0096] Specifically, the power of the machine tool can be turned on, an appropriate rotating speed can be set, the machine tool spindle can be started to rotate at the set rotating speed, and the tool mirror can be driven to rotate synchronously.

[0097] S13, emitting a laser beam to the prism reflection head of the tool mirror through the laser emitter.

[0098] Specifically, the position and angle of the laser emitter can be adjusted so that the laser beam emitted thereby can accurately irradiate the reflection plane of the prism reflection head.

[0099] The incident angle of the laser beam on the reflection plane can be optimized according to the position of the reflection plane to obtain the best reflection effect.

[0100] S14, receiving the laser beam reflected by the prism reflection head through the laser receiver.

[0101] Specifically, when the laser beam is reflected by the reflection plane of the prism reflection head to the laser receiver, the laser receiver receives the laser beam and converts it into an electric signal for subsequent processing.

[0102] S15, determining the distance between each reflection plane of the prism reflection head and the laser emitter through the triangulation method based on the received laser beam.

[0103] In the embodiment, the distance between the current reflection plane and the laser transmitter is accurately calculated by using the known geometric relationship (such as the emission angle, the receiving angle, the distance between the laser transmitter and the laser receiver, etc.) and combining the simple triangle geometric principle, and then the actual spatial position of the reflection plane is determined. In the spindle error measurement of the machine tool, this method can realize high-precision real-time online monitoring, is suitable for precision machining occasions, and compared with the laser interferometer measurement method, does not need expensive imported light sources and complex optical platforms, and reduces the equipment cost.

[0104] Further, with the rotation of the machine tool spindle, each reflection plane of the prism reflection head reflects the laser beam in turn to participate in measurement, so that the laser receiver can receive multiple laser beams to collect measurement data of multiple reflection planes during one rotation of the machine tool spindle. Based on the above measurement data, the distance between each reflection plane of the prism reflection head and the laser transmitter is determined by the triangulation method, which can reflect the displacement error of the machine tool spindle at different angles.

[0105] S16, determining the error of the machine tool spindle when rotating based on the distance between each reflection plane of the prism reflection head and the laser transmitter.

[0106] Specifically, the distance data of the multiple reflection planes at different rotation positions are comprehensively analyzed, and the dynamic error data of the machine tool spindle when rotating, such as the center offset error and the tool head swing error, are analyzed by using the spindle error analysis algorithm.

[0107] The machine tool spindle dynamic error measurement method provided by the embodiment of the application can measure dynamic errors during normal operation of the machine tool, realize monitoring of dynamic errors caused by high-speed rotation, temperature change, vibration and other factors during actual work of the machine tool, make the measured error information more accurate, and further based on the measured dynamic errors, the feed parameters or tool path of the machine tool can be adjusted by using the machine tool error compensation algorithm to realize dynamic correction and error compensation of the tool movement track, and ensure the machining precision of the workpiece. The method is simple and easy to implement, does not need expensive imported light sources and complex optical platforms, has low equipment cost, and can be applied to various types of machine tools, whether standard models or customized models, and can provide effective dynamic error measurement solutions.

[0108] Figure 6 The flowchart of another machine tool spindle dynamic error measurement method provided by the embodiment of the application is shown in FIG. 2. Figure 6 As shown in FIG. 2, before the tool mirror is installed on the machine tool spindle, the method further includes:

[0109] S101, determine the diameter of the mirror handle of the tool mirror based on the rotating speed of the machine tool spindle, wherein the greater the rotating speed of the machine tool spindle, the smaller the diameter of the mirror handle of the tool mirror.

[0110] When the rotating speed of the machine tool spindle increases, the centrifugal force of the tool mirror will increase significantly, which is easy to cause vibration and measurement error.

[0111] In this embodiment, tool mirrors with different mirror handle diameters are selected at different machine tool spindle rotating speeds, and the greater the machine tool spindle rotating speed, the smaller the diameter of the mirror handle of the selected tool mirror. When the tool mirror is installed on the machine tool spindle, the tool mirror with the corresponding mirror handle diameter is installed on the machine tool spindle to reasonably match the mirror handle size and the machine tool spindle rotating speed, achieve better mechanical balance, and thus reduce the influence of centrifugal force, reduce vibration interference, avoid measurement error caused by eccentricity, and improve the stability and accuracy of error measurement.

[0112] For example, when the rotating speed of the machine tool spindle is more than 10,000 revolutions, a mirror handle with a diameter less than or equal to 4.0 mm is selected; when the rotating speed of the machine tool spindle is more than 20,000 revolutions, a mirror handle with a diameter less than or equal to 3.0 mm is selected; and when the rotating speed of the machine tool spindle is more than 30,000 revolutions, a mirror handle with a diameter less than or equal to 1.8 mm is selected, so as to effectively control the centrifugal force under high-speed rotation by selecting an appropriate mirror handle diameter, reduce vibration interference, and ensure the dynamic stability of the tool mirror during rotation, but not limited thereto.

[0113] Figure 7 Another flowchart of a machine tool spindle dynamic error measurement method provided by the embodiment of the present application is shown in FIG. 5, which can optionally include the following steps before the tool mirror is installed on the machine tool spindle: Figure 7

[0114] S102, determine the number of reflection planes in the prism reflection head based on the target error measurement accuracy, wherein the higher the target error measurement accuracy, the greater the number of reflection planes in the prism reflection head.

[0115] The target error measurement accuracy refers to the minimum detectable error or the maximum allowable error range that is expected to be achieved during error measurement.

[0116] It can be understood that the more the number of reflection planes of the prism reflection head, the more the measurement point data collected by the machine tool spindle during one revolution, and the more accurate the error analysis result.

[0117] ​In the embodiment, the tool mirror with different number of reflection planes is selected under different target error measurement accuracy, and the higher the target error measurement accuracy is, the more the number of reflection planes of the tool mirror is selected. When the tool mirror is installed on the machine tool spindle, the tool mirror with corresponding number of reflection planes is installed on the machine tool spindle to reasonably match the number of reflection planes and the target error measurement accuracy, and the measurement efficiency and accuracy requirements are considered.

[0118] Specifically, when a higher target error measurement accuracy is required, a tool mirror with more reflection planes is selected to improve the sampling density and enhance the error identification capability; and under the condition of lower target error measurement accuracy, the number of reflection planes can be appropriately reduced, which is beneficial to reduce the manufacturing difficulty and cost of the tool mirror.

[0119] Optionally, at the same machine tool spindle speed, at least two different tool mirrors (for example, different mirror handle diameters and / or different number of reflection planes) are used for multiple measurements, the error data obtained by each measurement is recorded, and the difference between each group of error data is calculated. If the difference between all measurement results is within the preset error range, the measurement result is confirmed to be valid; otherwise, the tool mirror can be replaced or the optical path is optimized and then the measurement is performed again until the error measurement accuracy requirement is met.

[0120] Among them, through the comparison measurement of multiple groups of tool mirrors, the consistency of the measurement results is verified, which can enhance the reliability of the error measurement.

[0121] It should be understood that various forms of the flow shown above can be used to reorder, add or delete steps. For example, each step described in the present application can be executed in parallel, sequentially or in different order, as long as the desired results of the technical solutions of the present application can be achieved, which is not limited herein.

[0122] The above specific embodiments do not constitute a limitation on the scope of protection of the present application. Those skilled in the art should understand that various modifications, combinations, sub-combinations and substitutions can be made according to design requirements and other factors. Any modification, equivalent replacement and improvement within the spirit and principles of the present application should be included in the scope of protection of the present application.

Claims

1. A machine tool spindle dynamic error measuring device, characterized in that, Includes a blade mirror, a laser emitter, and a laser receiver; The tool mirror includes a prism reflector head and a mirror handle. One end of the mirror handle is connected to the prism reflector head, and the other end of the mirror handle is used to connect to the machine tool spindle. The laser emitter is used to emit a laser beam toward the prism reflector head; The laser receiver is used to receive the laser beam reflected by the prism reflector; The prism reflector includes multiple reflective planes, which are arranged circumferentially along the prism reflector. When the machine tool spindle drives the tool mirror to rotate, each of the reflecting planes sequentially reflects the laser beam emitted by the laser emitter to the laser receiver.

2. The machine tool spindle dynamic error measuring device according to claim 1, characterized in that, Each of the aforementioned reflective planes is parallel to the centerline of the machine tool spindle.

3. The machine tool spindle dynamic error measuring device according to claim 1, characterized in that, The multiple reflecting planes are evenly arranged along the circumference of the prism reflecting head.

4. The machine tool spindle dynamic error measuring device according to claim 1, characterized in that, The number of reflecting planes in the prism reflector head is greater than or equal to 3.

5. The machine tool spindle dynamic error measuring device according to claim 1, characterized in that, The prism reflector and the handle of the blade mirror are an integral structure.

6. The machine tool spindle dynamic error measuring device according to claim 4, characterized in that, The centerline of the machine tool spindle lies within the spatial plane formed by the laser emitter, the laser receiver, and the tool mirror.

7. The machine tool spindle dynamic error measuring device according to claim 1, characterized in that, The diameter of the prism reflector is greater than, equal to, or less than the diameter of the mirror handle.

8. A method for measuring the dynamic error of a machine tool spindle, characterized in that, The machine tool spindle dynamic error measuring device according to any one of claims 1-7; The method for measuring the dynamic error of the machine tool spindle includes: The tool mirror is mounted on the machine tool spindle; Start the machine tool so that the machine tool spindle drives the tool mirror to rotate; A laser beam is emitted from the laser emitter toward the prism reflector of the blade mirror; The laser beam reflected by the prism reflector is received by the laser receiver; Based on the received laser beam, the distance between each of the reflecting planes of the prism reflector and the laser emitter is determined by triangulation. The error of the machine tool spindle during rotation is determined based on the distance between each of the reflecting planes of the prism reflector and the laser emitter.

9. The method for measuring the dynamic error of a machine tool spindle according to claim 8, characterized in that, Before mounting the tool mirror onto the machine tool spindle, the method further includes: The diameter of the handle of the tool mirror is determined based on the rotational speed of the machine tool spindle, wherein the greater the rotational speed of the machine tool spindle, the smaller the diameter of the handle of the tool mirror.

10. The method for measuring the dynamic error of a machine tool spindle according to claim 8, characterized in that, Before mounting the tool mirror onto the machine tool spindle, the method further includes: The number of reflecting planes in the prism reflector head is determined based on the target error measurement accuracy, wherein the higher the target error measurement accuracy, the more reflecting planes in the prism reflector head.

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