A real-time online monitoring device for CNC machine tool workpieces

Abstract

The invention discloses a real-time online monitoring device for a CNC machine tool workpiece, and belongs to the technical field of machine tool equipment. A sensor mounting seat is fixedly connected to a transition plate by screws, a laser sensor is mounted on the sensor mounting seat, a movable joint is provided at the end of a data transmission cable of the laser sensor, the transition plate is fixedly connected to a transverse and longitudinal displacement adjustment device by a taper shank rivet on its upper portion, the fixed joint is mounted on the lower end surface of the transverse and longitudinal displacement adjustment device, the movable joint is connected to the fixed joint, the data transmission cable connected to the tail end of the fixed joint is connected to a host computer, the transverse and longitudinal displacement adjustment device is located on the left side of the workpiece on the machine tool worktable, the tool is located on the right side of the workpiece on the machine tool worktable, the transverse and longitudinal displacement adjustment device controls the laser sensor to maintain a non-contact state with the workpiece, the laser sensor measures the displacement value between it and the workpiece surface in real time online under the cutting state of the machine tool, and the accuracy data such as various errors of the workpiece can be obtained by solving the measurement data by the host computer.

Description

Technical Field

[0001] The invention relates to a real-time online monitoring device for a workpiece of a numerical control machine tool, belonging to the technical field of machine tool equipment. Background Art

[0002] Due to their large size and large load, large CNC machine tools often produce large removal volumes when machining large workpieces. Within a large scale range, the workpiece error increases. At present, the workpiece accuracy measurement of CNC machine tools can only be stopped for in-situ inspection after completing a certain process, or moved to a dedicated inspection platform for accuracy measurement, which seriously affects the processing efficiency. Since the existing measurement methods all use contact measurement methods, it is impossible to achieve real-time online measurement when the CNC machine tool is working, which restricts the development of real-time accuracy compensation technology for CNC machine tools and limits the further improvement of CNC machine tool processing accuracy. Summary of the invention

[0003] In order to solve the above-mentioned deficiencies in the prior art, the present invention provides a real-time online monitoring device for CNC machine tool workpieces. The device measures the displacement value between the device and the workpiece surface in real time online while maintaining non-contact with the workpiece, and transmits the measured data to the host computer through a data transmission cable. By using the detected parameters and solving the data through the host computer, the accuracy data such as the geometric size accuracy, roundness error, cylindricity error, workpiece installation eccentricity and machine tool spindle rotation error of the workpiece can be obtained.

[0004] The technical solution adopted by the present invention to solve its technical problems is: a real-time online monitoring device for CNC machine tool workpieces, including a laser sensor, a sensor mounting seat, a transition plate, screws, a movable joint, a fixed joint, a data transmission cable and a transverse and longitudinal displacement adjustment device. The sensor mounting seat is fixedly connected to the transition plate by screws, the laser sensor is installed on the sensor mounting seat, and a movable joint is provided at the end of the data transmission cable of the laser sensor. The movable joint can follow the movement of the sensor mounting seat, the transition plate is fixedly connected to the transverse and longitudinal displacement adjustment device through a tapered handle rivet on its upper part, the fixed joint is installed on the lower end surface of the transverse and longitudinal displacement adjustment device, the movable joint is connected to the fixed joint, and the data transmission cable connected to the tail end of the fixed joint is connected to the host computer. The horizontal and vertical displacement adjustment device is the left CNC tool holder. The tapered shank on the upper part of the transition plate can be accurately positioned at the inner tapered hole of the left CNC tool holder and be firmly tightened. The fixed joint is installed on the lower end face of the left CNC tool holder. The data transmission cable connected to the tail end of the fixed joint is located in the channel inside the left CNC tool holder and is connected to the host computer. The left CNC tool holder is precisely controlled by the CNC machine tool. The left CNC tool holder is located on the left side of the workpiece on the machine tool workbench, and the right CNC tool holder is located on the right side of the workpiece on the machine tool workbench. The right CNC tool holder is equipped with a tool for cutting. The left CNC tool holder controls the laser sensor to maintain a non-contact state with the workpiece and determines the detection position of the laser sensor for real-time monitoring. When no monitoring is required, the transition plate can be directly removed and the tool can be replaced for double-tool processing.

[0005] When the CNC machine tool is working, the machine tool worktable drives the workpiece to rotate, the tool cuts the workpiece, the laser sensor maintains a non-contact state with the workpiece, and measures the displacement value between it and the workpiece surface in real time online when the CNC machine tool is working. The measurement data is transmitted to the host computer through the data transmission cable. The host computer solves the data and obtains the workpiece's geometric size accuracy, roundness error, cylindricity error, workpiece installation eccentricity, machine tool spindle rotation error and other accuracy data.

[0006] When the height of the workpiece changes, the horizontal and vertical displacement adjustment device drives the laser sensor, sensor mounting seat and other components to move in the vertical direction to ensure that the laser sensor is accurately positioned in the vertical direction and realize the measurement of changes in the height direction of the workpiece. When the diameter of the workpiece changes, the horizontal and vertical displacement adjustment device drives the laser sensor, sensor mounting seat and other components to move in the horizontal direction to ensure that the laser sensor is accurately positioned in the horizontal direction and realize the measurement of changes in the diameter direction of the workpiece.

[0007] Furthermore, when the machine tool is a single-tool holder machine tool, the transverse and longitudinal displacement adjustment device is composed of a transverse bar, a longitudinal bar and a cross slider. The bottom end of the longitudinal bar is fixedly supported on the ground, the cross slider can move vertically on the longitudinal bar, and the transverse bar can move horizontally relative to the cross slider. The cross slider is provided with locking screws for locking vertical and horizontal movements. A sensor mounting seat is provided at the end of the transverse bar, and a fixed joint is installed on the slider. The data transmission cable connected to the tail end of the fixed joint is led out from the bottom of the longitudinal bar and connected to the host computer. The height is controlled by adjusting the position of the cross slider on the longitudinal bar. By adjusting the extended length of the transverse bar, the laser sensor is kept in a non-contact state at a certain distance from the workpiece for real-time monitoring. The laser sensor is kept on the opposite side of the tool of the single-tool holder machine tool with the workpiece as the center, avoiding high-temperature erosion caused by iron chips and iron slag during turning, protecting the normal operation of the sensor, avoiding vibration during chip cutting at the tool, and improving measurement accuracy.

[0008] The beneficial effects of the present invention are as follows: it avoids the unfavorable factors such as low detection efficiency and poor detection consistency of the traditional manual contact measurement method, and the secondary positioning error when the workpiece is moved to the special detection platform, thereby improving the processing accuracy and efficiency of the CNC machine tool. The device fully considers the factors such as the offset error and the rotation error existing in the CNC machine tool processing system, and combines the laser sensor with the CNC machine tool. When the CNC machine tool is working, the machine tool worktable drives the workpiece to rotate, and the CNC tool holder cuts the workpiece. The laser sensor and the workpiece are kept in a non-contact state and are located on the opposite side of the tool to avoid the high temperature erosion caused by the iron chips and iron slag during the turning process, protect the normal operation of the sensor, avoid the vibration of the tool during the chip cutting process, improve the measurement accuracy, realize the real-time online monitoring function of the workpiece of the CNC machine tool in the working state, and transmit the measurement data to the host computer through the data transmission cable. By using the detected parameters and solving the data through the host computer, the geometric size accuracy, roundness error, cylindricity error, workpiece installation eccentricity and machine tool spindle rotation error and other precision data of the workpiece can be obtained, which lays a foundation for the real-time precision compensation technology of the CNC machine tool.

[0009] This invention belongs to the Heilongjiang Provincial Science and Technology Plan Provincial Academy Science and Technology Cooperation Project "Research on Real-time Online Monitoring Technology of Intelligent Machine Tool Workpieces", project number: YS19A15. BRIEF DESCRIPTION OF THE DRAWINGS

[0010] The present invention is further described below in conjunction with the accompanying drawings and specific embodiments.

[0011] Figure 1 It is a structural schematic diagram of the present invention.

[0012] Figure 2 It is a schematic diagram of the structure of the present invention installed on a double tool post lathe.

[0013] Numbers in the figure:

[0014] 1. Laser sensor, 2. Sensor mounting base, 3. Transition plate, 4. Screws, 5. Moving joint, 6. Fixed joint, 7. Data transmission cable, 8. Left CNC tool holder, 9. Right CNC tool holder, 10. Machine tool workbench, 11. Workpiece. DETAILED DESCRIPTION

[0015] like Figure 1-2 As shown, a real-time online monitoring device for a CNC machine tool workpiece includes a laser sensor 1, a sensor mounting seat 2, a transition plate 3, screws 4, a movable joint 5, a fixed joint 6, a data transmission cable 7 and a transverse and longitudinal displacement adjustment device. The sensor mounting seat 2 is fixedly connected to the transition plate 3 by screws 4, the laser sensor 1 is mounted on the sensor mounting seat 2, and a movable joint 5 is provided at the end of the data transmission cable 7 of the laser sensor 1. The movable joint 5 can follow the sensor mounting seat 2, the transition plate 3 is fixedly connected to the transverse and longitudinal displacement adjustment device through the cone handle rivet on its upper part, the fixed joint 6 is installed on the lower end surface of the transverse and longitudinal displacement adjustment device, the movable joint 5 is connected to the fixed joint 6, and the data transmission cable 7 connected to the tail end of the fixed joint 6 is connected to the host computer, and the transverse and longitudinal displacement adjustment device is left CNC tool rest 8, the tapered shank on the upper part of the transition disk 3 can be accurately positioned at the inner tapered hole of the left CNC tool rest 8 and be firmly tightened, the fixed joint 6 is installed on the lower end surface of the left CNC tool rest 8, and the data transmission cable 7 connected to the tail end of the fixed joint 6 is located in the channel inside the left CNC tool rest 8 and is connected to the host computer. The left CNC tool rest 8 is precisely controlled by the CNC machine tool. The left CNC tool rest 8 is located on the left side of the workpiece 11 on the machine tool workbench 10, and the right CNC tool rest 9 is located on the right side of the workpiece 11 on the machine tool workbench 10. A tool is installed on the right CNC tool rest 9 for cutting. The left CNC tool rest 8 controls the laser sensor 1 to maintain a non-contact state with the workpiece 11, and determines the detection position of the laser sensor 1 for real-time monitoring. When no monitoring is needed, the transition disk 3 can be directly removed and the tool can be replaced for double-knife processing.

[0016] When the CNC machine tool is working, the machine tool worktable 10 drives the workpiece 11 to rotate, the tool cuts the workpiece 11, the laser sensor 1 maintains a non-contact state with the workpiece 11, and measures the displacement value between it and the surface of the workpiece 11 in real time online when the CNC machine tool is working, and transmits the measured data to the host computer through the data transmission cable 7. The host computer solves the data and obtains the accuracy data such as the geometric size accuracy, roundness error, cylindricity error, workpiece installation eccentricity and machine tool spindle rotation error of the workpiece.

[0017] When the height of the workpiece 11 changes, the horizontal and vertical displacement adjustment device drives the laser sensor 1, the sensor mounting seat 2 and other components to move in the vertical direction, ensuring that the laser sensor 1 is accurately positioned in the vertical direction, and realizing the measurement of the change in the height direction of the workpiece 11. When the diameter of the workpiece 11 changes, the horizontal and vertical displacement adjustment device drives the laser sensor 1, the sensor mounting seat 2 and other components to move in the horizontal direction, ensuring that the laser sensor 1 is accurately positioned in the horizontal direction, and realizing the measurement of the change in the diameter direction of the workpiece 11.

[0018] Furthermore, when the machine tool is a single-tool holder machine tool, the transverse and longitudinal displacement adjustment device is composed of a transverse bar, a longitudinal bar and a cross slider. The bottom end of the longitudinal bar is fixedly supported on the ground, the cross slider can move vertically on the longitudinal bar, and the transverse bar can move horizontally relative to the cross slider. The cross slider is provided with locking screws for locking vertical and horizontal movements. A sensor mounting seat 2 is provided at the end of the transverse bar, and a fixed joint 6 is installed on the slider. The data transmission cable 7 connected to the tail end of the fixed joint 6 is led out from the bottom of the longitudinal bar and connected to the host computer. The height is controlled by adjusting the position of the cross slider on the longitudinal bar. By adjusting the extended length of the transverse bar, the laser sensor 1 is kept in a non-contact state at a certain distance from the workpiece 11 for real-time monitoring. The laser sensor 1 is kept on the opposite side of the tool of the single-tool holder machine tool with the workpiece 11 as the center, avoiding high-temperature erosion caused by iron chips and iron slag during turning, protecting the normal operation of the sensor, avoiding vibration during chip cutting at the tool, and improving measurement accuracy.

Claims

1. A real-time online monitoring device for a CNC machine tool workpiece, characterized in that: The invention comprises a laser sensor (1), a sensor mounting seat (2), a transition plate (3), screws (4), a movable joint (5), a fixed joint (6), a data transmission cable (7) and a transverse and longitudinal displacement adjustment device, wherein the sensor mounting seat (2) and the transition plate (3) are fixedly connected by means of screws (4), the laser sensor (1) is mounted on the sensor mounting seat (2), a movable joint (5) is provided at the end of the data transmission cable (7) of the laser sensor (1), and the movable joint (5) can follow the movement of the sensor mounting seat (2), the transition plate (3) is fixedly connected to the transverse and longitudinal displacement adjustment device by means of a taper shank rivet at the upper portion thereof, the fixed joint (6) is mounted on the lower end surface of the transverse and longitudinal displacement adjustment device, the movable joint (5) is connected to the fixed joint (6), and the data transmission cable (7) connected to the tail end of the fixed joint (6) 7) is connected to the host computer, the horizontal and vertical displacement adjustment device is a left CNC tool holder (8), the tapered handle on the upper part of the transition plate (3) can be accurately positioned at the inner tapered hole of the left CNC tool holder (8) and is firmly tightened, the fixed joint (6) is installed on the lower end surface of the left CNC tool holder (8), the data transmission cable (7) connected to the tail end of the fixed joint (6) is located in the channel inside the left CNC tool holder (8) and is connected to the host computer, the left CNC tool holder (8) is accurately controlled by the CNC machine tool, the left CNC tool holder (8) is located on the left side of the workpiece (11) on the machine tool worktable (10), the right CNC tool holder (9) is located on the right side of the workpiece (11) on the machine tool worktable (10), the right CNC tool holder (9) is installed with a tool, and the left CNC tool holder (8) controls the laser sensor (1) to maintain a non-contact state with the workpiece (11).

2. The real-time online monitoring device for a CNC machine tool workpiece according to claim 1, characterized in that: When the machine tool is a single-tool rest machine tool, the transverse and longitudinal displacement adjustment device is composed of a transverse bar, a longitudinal bar and a cross slide, the bottom end of the longitudinal bar is fixedly supported on the ground, the cross slide can move vertically on the longitudinal bar, the transverse bar can move horizontally relative to the cross slide, and the cross slide is provided with a locking screw for locking the vertical and horizontal movements. A sensor mounting seat (2) is provided at the end of the transverse bar, a fixed joint (6) is installed on the slide, a data transmission cable (7) connected to the tail end of the fixed joint (6) is led out from under the longitudinal bar and connected to a host computer, and the laser sensor (1) maintains an opposite surface to the tool of the single-tool rest machine tool with the workpiece (11) as the center.

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