Device for detecting relative displacement of spindle end of numerical control machine tool

Abstract

The utility model relates to a numerical control machine tool main shaft end relative displacement detection device comprising a pedestal support fixed with a numerical control machine tool workbench; the measuring head base is arranged above the base bracket; a wired measuring head and a blowing nozzle are arranged on the measuring head base, and a measuring rod is arranged on one side of the wired measuring head; and the end cover protective cover is arranged on the outer side of the measuring head base and is used for protecting the wired measuring head. And the protective cover moving mechanism is arranged on the base bracket, is connected with the end cover protective cover, and is used for driving the end cover protective cover to horizontally slide towards the direction of the measuring rod. The device can be directly installed and fixed on the working table of the numerical control machine tool without changing the original structure of the numerical control machine tool, and is simple to implement and deploy; an operator calls a detection program through common codes of the numerically-controlled machine tool, the position deviation of the spindle end of the numerically-controlled machine tool can be measured, operation is convenient, and the machining precision of the numerically-controlled machine tool can be greatly improved.

Description

Technical Field

[0001] This utility model relates to the field of precision machining technology of CNC machine tools, and in particular to a relative displacement detection device for the spindle end of a CNC machine tool. Background Technology

[0002] As a key piece of equipment in modern manufacturing, CNC machine tools' core function is to perform precision machining of workpieces through a CNC system. The operation of a CNC machine tool relies on compiling machining information, such as the workpiece's geometric data and process data, into a CNC machining program according to prescribed codes and formats, and then inputting this program into the CNC system. After processing these programs, the system outputs corresponding information and instructions, controlling the various parts of the machine tool to move in a prescribed and orderly manner to ensure the accuracy of the relative position between the tool and the workpiece. The precise spatial position of the CNC machine tool spindle directly affects the dimensional accuracy of the machined parts; therefore, precise control of the spindle is crucial for ensuring machining quality.

[0003] In the field of precision machining on CNC machine tools, grating rulers are widely used as an auxiliary tool to improve tool path accuracy. A grating ruler, also known as a grating ruler displacement sensor, works based on the optical principle of a grating and consists of two parts: a scale grating and a grating reading head. The scale grating is usually fixed to a stationary part of the machine tool, while the grating reading head is mounted on a moving part. The measurement output signal of the grating ruler is a digital pulse, characterized by a large detection range, high detection accuracy, and fast response speed. In the closed-loop servo system of CNC machine tools, grating rulers are often used to detect linear or angular displacement to observe and track tool path errors, thereby compensating for tool movement errors, ensuring the tool path accuracy of the machine tool, and providing excellent auxiliary effects for machining accuracy.

[0004] While linear encoders play a significant role in improving the machining accuracy of CNC machine tools, existing technologies have some obvious shortcomings. First, related products are mainly sourced from European and American manufacturers, resulting in high operating costs. Second, the installation process is cumbersome, requiring high precision and stability of the CNC machine tool's mounting surface, and installation after the machine tool leaves the factory is difficult, leading to complex maintenance. Most importantly, linear encoders can only directly measure the linear or rotary axis displacement accuracy of the X / Y / Z axes of CNC machine tools, and cannot detect errors caused by structural deformation.

[0005] Therefore, there is an urgent need for a relative displacement detection device for the spindle end of a CNC machine tool to address the shortcomings of existing technologies. Utility Model Content

[0006] Therefore, the technical problem to be solved by this utility model is to overcome the shortcomings of the prior art and provide a relative displacement detection device for the spindle end of a CNC machine tool. It can be directly installed and fixed on the worktable of the CNC machine tool without changing the original structure of the CNC machine tool, and the implementation and deployment are simple. The operator can call the detection program through the common CNC machine tool code to realize the measurement of the position deviation of the zero point position of the linear axis of the CNC machine tool product X / Y / Z / or the position deviation of the spindle end of the CNC machine tool caused by the structural deformation of the CNC machine tool. It is convenient to operate and can greatly improve the machining accuracy of the CNC machine tool.

[0007] To solve the above-mentioned technical problems, this utility model provides a relative displacement detection device for the spindle end of a CNC machine tool, comprising:

[0008] The base bracket is fixed to the CNC machine tool worktable;

[0009] A probe base is placed above the base bracket; a wired probe and an air nozzle are provided on the probe base, and a measuring rod is provided on one side of the wired probe;

[0010] An end cap protective cover is disposed on the outside of the probe base to protect the wired probe.

[0011] A protective cover moving mechanism is mounted on the base bracket and connected to the end cover protective cover, used to drive the end cover protective cover to slide horizontally toward the measuring rod.

[0012] In one embodiment of this utility model, a stepped hole is provided on the probe base, and the wired probe is disposed in the stepped hole.

[0013] In one embodiment of the present invention, the stepped hole includes a first stepped hole section and a second stepped hole section connected to each other, the diameter of the first stepped hole section is larger than the diameter of the second stepped hole section, and the first stepped hole section is a threaded hole.

[0014] In one embodiment of this utility model, the cable of the wired probe passes through the second stepped hole section and is connected to the CNC machine tool electrical system.

[0015] In one embodiment of this utility model, a first through hole is provided on the probe base, and the two ends of the first through hole are a first threaded hole section and a second threaded hole section, respectively.

[0016] In one embodiment of the present invention, the air nozzle is installed in the first threaded hole section, one end of the air nozzle is connected to an air connector, and the air connector is disposed in the second threaded hole section.

[0017] In one embodiment of this utility model, the air connector of the air nozzle is connected to an air source via an air pipe, and the air source is controlled by an external solenoid valve of the machine tool.

[0018] In one embodiment of this utility model, the probe base is provided with two second through holes for mounting screws to fix it to the base bracket.

[0019] In one embodiment of this utility model, the protective cover moving mechanism includes a miniature cylinder and a cylinder slide rod. The driving end of the miniature cylinder is connected to the cylinder slide rod. Electromagnetic induction switches are provided on both sides of the miniature cylinder, and an air inlet connector is provided on the top of the miniature cylinder.

[0020] In one embodiment of this utility model, the miniature cylinder is fixed on the base bracket by a cylinder bracket.

[0021] Compared with the prior art, the above-mentioned technical solution of this utility model has the following beneficial effects:

[0022] (1) It can be directly installed and fixed on the CNC machine tool worktable through the base bracket without changing the original structure of the CNC machine tool, and the implementation and deployment are simple; the operator can call the detection program through the common CNC machine tool code to realize the measurement of the zero position offset of the linear axis of the CNC machine tool product X / Y / Z / or the position deviation of the CNC machine tool spindle end caused by the deformation of the CNC machine tool structure. It is convenient to operate and can greatly improve the machining accuracy of the CNC machine tool.

[0023] (2) The probe base simultaneously fixes the wired probe and the air blowing device to achieve clean measurement and further improve the detection stability and accuracy; the probe base is equipped with an end cover protective cover, and the end cover protective cover can move and extend towards the measuring rod to protect the wired probe. Attached Figure Description

[0024] To make the content of this utility model easier to understand, the present utility model will be further described in detail below with reference to specific embodiments and accompanying drawings.

[0025] Figure 1 This is a schematic diagram of the structure of the relative displacement detection device at the spindle end of a CNC machine tool in a preferred embodiment of the present invention;

[0026] Figure 2 for Figure 1 A schematic diagram of the internal structure of the probe base of the relative displacement detection device at the spindle end of a CNC machine tool.

[0027] Figure 3 for Figure 1 The diagram shows the structure of the probe base, wired probe, and air nozzle.

[0028] Explanation of reference numerals in the accompanying drawings: 1. Base bracket; 2. Probe base; 21. Step hole; 211. First step hole section; 212. Second step hole section; 3. Protective cover moving mechanism; 30. Miniature cylinder; 34. Cylinder slide rod; 4. End cover protective cover; 5. Wired probe; 6. Air nozzle; 7. CNC machine tool spindle; 8. Measuring rod. Detailed Implementation

[0029] The present invention will be further described below with reference to the accompanying drawings and specific embodiments, so that those skilled in the art can better understand and implement the present invention. However, the embodiments are not intended to limit the present invention.

[0030] Reference Figure 1 As shown, this utility model discloses a relative displacement detection device for the spindle end of a CNC machine tool, comprising:

[0031] Base bracket 1 is fixed to the CNC machine tool worktable;

[0032] The probe base 2 is placed above the base bracket 1; the probe base 2 is provided with a wired probe 5 and an air nozzle 6, and a measuring rod 8 is provided on one side of the wired probe 5;

[0033] The end cap protective cover 4 is disposed on the outside of the probe base 2 and is used to protect the wired probe 5.

[0034] The protective cover moving mechanism 3 is mounted on the base bracket 1 and connected to the end cover protective cover 4, and is used to drive the end cover protective cover 4 to slide horizontally toward the measuring rod.

[0035] A stepped hole 21 is provided on the probe base 2, and the wired probe 5 is disposed in the stepped hole 21.

[0036] The stepped hole 21 includes a first stepped hole section 211 and a second stepped hole section 212 that are connected to each other. The diameter of the first stepped hole section 211 is larger than the diameter of the second stepped hole section 212, and the first stepped hole section 211 is a threaded hole.

[0037] The cable of the wired probe 5 passes through the second step hole section 212 and connects to the electrical system of the CNC machine tool. The repeatability of the wired probe 5 is 0.001mm, and it has an IP68 deep waterproof rating.

[0038] The probe base 2 is provided with a first through hole 22, and the two ends of the first through hole 22 are a first threaded hole section 221 and a second threaded hole section 222, respectively.

[0039] An air nozzle 6 is installed in the first threaded hole section 221, and one end of the air nozzle 6 is connected to an air connector, which is located in the second threaded hole section 222.

[0040] The air nozzle 6 is connected to an air source via an air pipe, which is controlled by an external solenoid valve. During the testing process, the air source controls the flow of compressed air through the solenoid valve. When the solenoid valve is open, compressed air is blown through the air nozzle 6 to clean the wired probe 5 during testing, ensuring that there are no foreign objects affecting the measurement accuracy at the contact point between the measuring rod 8 on the wired probe 5 and the CNC machine tool spindle 7.

[0041] Two second through holes 23 are provided on the probe base 2 for installing screws to fix it to the base bracket 1.

[0042] The protective cover moving mechanism 3 includes a miniature cylinder 30 and a cylinder slide rod 34. The driving end of the miniature cylinder 30 is connected to the cylinder slide rod 34. Electromagnetic induction switches 32 are provided on both sides of the miniature cylinder 30, and an air inlet connector 33 is provided on the top of the miniature cylinder 30. There are two air inlet connectors 33, both of which are connected to a five-way solenoid valve to realize the extension and retraction of the cylinder slide rod 34. Each air inlet connector 33 is equipped with two electromagnetic induction switches to detect the extension and retraction status of the cylinder slide rod 34.

[0043] The end cap protective cover 4 is fixed to the end of the cylinder slide rod 34 and moves synchronously with the cylinder slide rod 34 to protect the wired probe 5.

[0044] The miniature cylinder 30 is fixed to the base bracket 1 by the cylinder bracket 31.

[0045] During operation, the relative displacement detection device of the CNC machine tool spindle end is connected to the industrial control computer. The detection program is called through the code of the CNC machine tool system. The cylinder slide rod 34 retracts, the end cover protective cover 4 opens, the end face of the CNC machine tool spindle 7 contacts the end face of the measuring rod 8, the wired probe 5 sends a signal, the CNC machine tool system calls the detection program to calculate the current position data of the end face of the CNC machine tool spindle 7 and compares it with the original calibration position data. The difference is compensated into the CNC machine tool system to improve the machining accuracy of the CNC machine tool.

[0046] In this embodiment, the electrical components used to control the miniature cylinder 3 need to control 3 sets of pneumatic valve groups and connect to 2 cylinder position input signal sensors to ensure the safety and functionality of this system.

[0047] The operating logic of the CNC machine tool spindle relative displacement detection device based on the above structure is divided into a system calibration section and a system measurement section. The main function of the system calibration section is to measure the machine body when its initial accuracy is completely normal, and record the corresponding data as the basis for subsequent compensation and adjustment. This step is called system calibration. After the machine has been used for a period of time, its operating accuracy may change due to various factors such as temperature, materials, and assembly. At this time, the measurement program is run, the system automatically runs and measures the current data, compares it with the previously measured calibration data, automatically calculates the difference between the two, and performs automatic coordinate compensation through corresponding calculations, thereby restoring the machine to its initial state of complete accuracy as much as possible.

[0048] Obviously, the above embodiments are merely illustrative examples for clear explanation and are not intended to limit the implementation. Those skilled in the art will recognize that other variations or modifications can be made based on the above description. It is neither necessary nor possible to exhaustively list all possible implementations here. However, obvious variations or modifications derived therefrom are still within the protection scope of this invention.

Claims

1. A relative displacement detection device for the spindle end of a CNC machine tool, characterized in that: include: The base bracket is fixed to the CNC machine tool worktable; A probe base is placed above the base bracket; a wired probe and an air nozzle are provided on the probe base, and a measuring rod is provided on one side of the wired probe; An end cap protective cover is disposed on the outside of the probe base to protect the wired probe; A protective cover moving mechanism is mounted on the base bracket and connected to the end cover protective cover, used to drive the end cover protective cover to slide horizontally toward the measuring rod.

2. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The probe base is provided with a stepped hole, and the wired probe is disposed in the stepped hole.

3. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 2, characterized in that: The stepped hole includes a first stepped hole section and a second stepped hole section that are connected to each other. The diameter of the first stepped hole section is larger than the diameter of the second stepped hole section, and the first stepped hole section is a threaded hole.

4. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 3, characterized in that: The cable of the wired probe passes through the second stepped hole section and connects to the electrical system of the CNC machine tool.

5. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The probe base is provided with a first through hole, and the two ends of the first through hole are a first threaded hole section and a second threaded hole section, respectively.

6. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The air nozzle is installed in the first threaded hole section, one end of the air nozzle is connected to an air connector, and the air connector is located in the second threaded hole section.

7. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The air nozzle's air connector is connected to an air source via an air pipe, and the air source is controlled by an external solenoid valve.

8. The relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The probe base is provided with two second through holes for installing screws to fix it to the base bracket.

9. A relative displacement detection device for the spindle end of a CNC machine tool according to claim 1, characterized in that: The protective cover moving mechanism includes a miniature cylinder and a cylinder slide rod. The driving end of the miniature cylinder is connected to the cylinder slide rod. Electromagnetic induction switches are provided on both sides of the miniature cylinder, and an air inlet connector is provided on the top of the miniature cylinder.

10. A relative displacement detection device for the spindle end of a CNC machine tool according to claim 9, characterized in that: The miniature cylinder is fixed to the base bracket by a cylinder bracket.

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