Full-closed-loop control testing machine convenient to install and used for numerical control machine tool

Abstract

The utility model relates to the technical field of numerical control machine tool application, in particular to a full-closed-loop control testing machine convenient to install for a numerical control machine tool, which comprises a base, a screw rod, a linear guide rail and a sliding block, a servo motor is installed on one side of the base, the screw rod is rotatably installed on the base, the linear guide rail is installed on the base, the sliding block is sleeved on the screw rod, and the servo motor is installed on the other side of the base. The servo motor drives the lead screw to rotate, the lead screw drives the sliding block to slide on the linear rail so that the sliding block can move on the lead screw, and a structure used for eliminating mechanical errors caused by thermal extension of the lead screw when the sliding block moves on the lead screw is installed on the base. After the synchronous ruler is mounted on the base, the control mode belongs to a full closed loop, the displacement precision of the machine tool is controlled by the synchronous ruler, the expansion coefficient of the material of the synchronous ruler is the same as that of a machine tool casting, the machine tool precision can be improved by using the synchronous ruler, mechanical errors caused by hot extension of a lead screw are eliminated, and the overall precision of the machine tool is greatly improved; and the processing precision requirements of customers are met.

Description

Technical Field

[0001] The utility model relates to the technical field of CNC machine tool applications, in particular to a fully closed-loop controlled testing machine for CNC machine tools which is easy to install. Background Art

[0002] The core of CNC machine tools is control accuracy. Currently, most machine tools on the market still use semi-closed loop control. Conventional digital machine tools are all semi-closed loop controlled, and the axis displacement accuracy is controlled by the encoder provided by the servo motor. This control method feeds back theoretical values, not actual running distance.

[0003] Moreover, conventional CNC machine tools use servo motor encoders to control the machine tool accuracy. The accuracy of the CNC machine tool axis movement is the moving distance calculated by the encoder and the lead screw pitch. The lead screw will heat up during long-term movement of the machine, and the lead screw will have thermal extension after heating, which will make the machine tool accuracy inaccurate.

[0004] As end users have increasingly higher requirements for the quality of machine tools, machine tool manufacturers are also paying attention to this issue. Utility Model Content

[0005] The purpose of the utility model is to provide a fully closed-loop controlled testing machine for CNC machine tools that is easy to install, so as to solve the problems raised in the above-mentioned background technology.

[0006] To achieve the above objectives, the present invention provides the following technical solutions:

[0007] A fully closed-loop controlled testing machine for a CNC machine tool that is easy to install, comprising:

[0008] A base, with a servo motor installed on one side of the base;

[0009] A screw rod, the screw rod being rotatably mounted on the base;

[0010] A linear rail, the linear rail being mounted on a base;

[0011] A slider, wherein the slider is sleeved on the screw rod;

[0012] The servo motor drives the screw to rotate, so that the screw drives the slider to slide on the linear rail, thereby achieving movement on the screw;

[0013] The base is provided with a structure for eliminating mechanical errors caused by thermal extension of the screw rod when the slider moves on the screw rod.

[0014] Preferably, the base includes a base and a left side plate and a right side plate respectively installed at two ends of the base.

[0015] Preferably, the servo motor is mounted on the right side plate / left side plate and is connected to one end of the lead screw via a coupling.

[0016] Preferably, a bracket is installed on the base, the other end of the screw rod passes through the bracket and is rotatably connected to the left plate / right plate, and the coupling is installed on the bracket.

[0017] Preferably, the structure includes a synchronization ruler, the synchronization ruler is located on the base, the slider is installed with a slider mounting bracket, and the slider mounting bracket slides on the synchronization ruler.

[0018] Preferably, a synchronization scale mounting bracket for fixing the synchronization scale is installed on the base.

[0019] Preferably, the expansion coefficient of the material of the synchronous ruler is the same as the expansion coefficient of the machine tool casting of the CNC machine tool.

[0020] Preferably, the spacing tolerance between the synchronization ruler and the slider is 0.25 mm ± 0.13 mm.

[0021] Compared with the prior art, the beneficial effects of the present invention are:

[0022] The utility model has a structure installed on the base for eliminating the mechanical error caused by the thermal expansion of the screw when the slider moves on the screw. Specifically, after the synchronization ruler is installed, the control mode is fully closed-loop, and the displacement accuracy of the machine tool is controlled by the synchronization ruler. The expansion coefficient of the synchronization ruler material is the same as that of the machine tool casting. The use of the Nidec synchronization ruler can improve the machine tool accuracy and eliminate the mechanical error caused by the thermal expansion of the screw.

[0023] By installing a synchronous ruler on a machine tool, the overall accuracy of the machine tool can be greatly improved, meeting the customer's machining accuracy requirements. The synchronous ruler is installed on a test machine for demonstration purposes, allowing customers to intuitively understand the full closed-loop function of the Nidec synchronous ruler. The demonstration machine is used for synchronous ruler communication testing of various systems and for demonstration training. BRIEF DESCRIPTION OF THE DRAWINGS

[0024] In order to more clearly illustrate the technical solutions of the embodiments of the present invention, the following briefly introduces the drawings required for use in the description of the embodiments. Obviously, the drawings described below are only some embodiments of the present invention. For ordinary technicians in this field, other drawings can be obtained based on these drawings without paying any creative work.

[0025] Figure 1 This is a structural diagram of a fully closed-loop controlled testing machine for a CNC machine tool that is easy to install, according to an exemplary embodiment of the present invention.

[0026] In the figure: 1-servo motor, 2-coupling, 3-linear rail, 4-screw, 5-right side plate, 6-bracket, 7-slider mounting bracket, 8-slider, 9-synchronizing ruler, 10-synchronizing ruler mounting bracket, 11-left side plate, 12-base, 13-guide rod, 14-handle, 15-base. DETAILED DESCRIPTION

[0027] The following will be combined with the drawings in the embodiments of the present invention to clearly and completely describe the technical solutions in the embodiments of the present invention. Obviously, the embodiments described are only some embodiments of the present invention, not all embodiments. The following description of at least one exemplary embodiment is actually only illustrative and is in no way intended to limit the present invention and its application or use. Based on the embodiments of the present invention, all other embodiments obtained by ordinary technicians in this field without making creative efforts are within the scope of protection of the present invention.

[0028] It should be noted that the terms used herein are only for describing specific embodiments and are not intended to limit the exemplary embodiments according to the present application. As used herein, unless the context clearly indicates otherwise, the singular form is also intended to include the plural form. In addition, it should be understood that when the terms "comprise" and / or "include" are used in this specification, they indicate the presence of features, steps, operations, devices, components and / or combinations thereof.

[0029] Unless otherwise specifically stated, the relative arrangement of the parts and steps, the numerical expressions and the numerical values ​​set forth in these embodiments do not limit the scope of the present invention. At the same time, it should be understood that, for ease of description, the sizes of the various parts shown in the drawings are not drawn according to the actual proportional relationship. The techniques, methods and equipment known to those of ordinary skill in the relevant art may not be discussed in detail, but where appropriate, the techniques, methods and equipment should be considered as part of the authorization specification. In all examples shown and discussed here, any specific values ​​should be interpreted as being merely exemplary and not as limitations. Therefore, other examples of the exemplary embodiments may have different values. It should be noted that similar numbers and letters represent similar items in the following figures, and therefore, once an item is defined in one figure, it does not need to be further discussed in subsequent figures.

[0030] In the description of the present invention, it needs to be understood that the directions or positional relationships indicated by directional words such as "front, back, up, down, left, right", "horizontal, vertical, vertical, horizontal" and "top, bottom" are usually based on the directions or positional relationships shown in the accompanying drawings. They are only for the convenience of describing the present invention and simplifying the description. Unless otherwise specified, these directional words do not indicate or imply that the device or element referred to must have a specific direction or be constructed and operated in a specific direction. Therefore, they cannot be understood as limiting the scope of protection of the present invention; the directional words "inside and outside" refer to the inside and outside relative to the outline of each component itself.

[0031] For ease of description, spatially relative terms such as "above", "above", "on the upper surface of", "above", etc. may be used herein to describe the spatial positional relationship of a device or feature to other devices or features as shown in the figures. It should be understood that spatially relative terms are intended to include different orientations of the device in use or operation in addition to the orientation described in the figures. For example, if the device in the drawings is inverted, the device described as "above other devices or structures" or "above other devices or structures" will be positioned as "below other devices or structures" or "below other devices or structures". Thus, the exemplary term "above" can include both "above" and "below". The device can also be positioned in other different ways (rotated 90 degrees or in other orientations), and the spatially relative descriptions used here are interpreted accordingly.

[0032] In addition, it should be noted that the use of words such as "first" and "second" to limit components is only for the convenience of distinguishing the corresponding components. Unless otherwise stated, the above words have no special meaning and therefore cannot be understood as limiting the scope of protection of this utility model.

[0033] See also Figure 1 , the utility model provides a technical solution:

[0034] A fully closed-loop controlled testing machine for a CNC machine tool that is easy to install, comprising:

[0035] A base 15, with a servo motor 1 mounted on one side of the base 15;

[0036] A screw rod 4, the screw rod 4 being rotatably mounted on the base 15;

[0037] Linear rail 3, the linear rail 3 is mounted on the base 15;

[0038] A slider 8, wherein the slider 8 is mounted on the screw rod 4;

[0039] The servo motor 1 drives the screw rod 4 to rotate, so that the screw rod 4 drives the slider 8 to slide on the linear rail 3, thereby realizing movement on the screw rod 4;

[0040] The base 15 is provided with a structure for eliminating mechanical errors caused by thermal expansion of the screw rod 4 when the slider 8 moves on the screw rod 4 .

[0041] In a specific embodiment, if Figure 1 As shown, the base 15 includes a base 12 and a left side plate 11 and a right side plate 5 respectively mounted on both ends of the base 12. The servo motor 1 is mounted on the right side plate 5 / left side plate 11 and connected to one end of the screw rod 4 through a coupling 2.

[0042] In a specific embodiment, if Figure 1 As shown, a bracket 6 is mounted on the base 12, the other end of the screw rod 4 passes through the bracket 6 and is rotatably connected to the left side plate 11 / right side plate 5, and the coupling 2 is mounted on the bracket 6. The screw rod 4 and the left side plate 11 / right side plate 5, as well as the screw rod 4 and the bracket 6, are engaged through bearings to achieve the rotation of the screw rod 4.

[0043] In a specific embodiment, if Figure 1 As shown, the structure includes a synchronous ruler 9, which is located on a base 12. The slider 8 is mounted with a slider mounting bracket 7, which slides on the synchronous ruler 9. A synchronous ruler mounting bracket 10 is mounted on the base 12 to secure the synchronous ruler 9. The slider mounting bracket 7 has a concave bottom that fits snugly on the synchronous ruler 9 and slides in conjunction with it.

[0044] In a specific embodiment, if Figure 1 As shown, the expansion coefficient of the material of the synchronous ruler 9 is the same as the expansion coefficient of the machine tool casting of the CNC machine tool.

[0045] In a specific embodiment, if Figure 1 As shown, the spacing tolerance between the synchronization ruler 9 and the slider 8 is 0.25 mm ± 0.13 mm.

[0046] In a specific embodiment, if Figure 1 As shown, a guide rod 13 for sliding the slider 8 is installed between the left side plate 11 and the right side plate 5. This makes the slider 8 more stable when it is driven by the screw rod 4 and moves left and right along the screw rod 4.

[0047] In a specific embodiment, if Figure 1 As shown, handles 14 are installed at both ends of the base 15 to facilitate moving the entire testing machine to a suitable location.

[0048] In the field of CNC machine tools, conventional CNC machine tools use servo motor encoders to control the accuracy of the machine tools. The accuracy of the CNC machine tool axis movement is the movement distance calculated by the encoder and the lead screw pitch:

[0049] If the lead screw is single-start, meaning it has only one thread, then the distance the lead screw moves is directly equal to the thread pitch multiplied by the number of pulses output by the encoder. For example, if the thread pitch is P mm and the encoder outputs N pulses, then the distance the lead screw moves is P × N mm.

[0050] For multi-start lead screws (such as double-start and triple-start), the lead screw has multiple threads. In this case, the distance the lead screw moves is the sum of the distances moved by each individual thread. For example, if a four-start lead screw has a pitch of 2 mm and the encoder outputs 4 pulses, this means that the servo motor rotates once, but because the lead screw has four starts, the actual distance moved is 4 × P mm, where P is the pitch of each individual thread. If the encoder outputs N pulses, the actual distance moved is N × P mm.

[0051] When the machine moves for a long time, the screw will heat up, and when the screw heats up, there will be thermal extension, which will make the machine tool accuracy inaccurate.

[0052] In order to solve the above-mentioned problem of inaccurate machine tool precision, the Nidec brand synchronous ruler currently sold by the company is used for full closed-loop control of CNC machine tools. The machine tool uses the Nidec brand synchronous ruler 9, which can improve the precision of CNC machine tools to 1m±2.5μm.

[0053] After the CNC machine tool is installed with the Nidec brand synchronous ruler, the control mode is fully closed-loop. The displacement accuracy of the machine tool is controlled by the synchronous ruler. The expansion coefficient of the synchronous ruler 9 material is the same as that of the machine tool casting. The use of the Nidec brand synchronous ruler can improve the machine tool accuracy and eliminate the mechanical error caused by the thermal expansion of the screw 4.

[0054] The utility model is applied to the Nidec synchronous ruler test machine platform for communication test between the synchronous ruler 9 and the numerical control system. The commonly used numerical control systems on the market include Mitsubishi, Fanuc, Siemens, Shindai, and Huazhong, which can all be used for communication test. The synchronous ruler 9 is installed on the test machine for display, allowing customers to intuitively understand the full closed-loop function of the Nidec synchronous ruler. The display machine is used for synchronous ruler communication test and display training of various systems.

[0055] This utility model uses a synchronized ruler 9 as a product for full closed-loop control of CNC machine tools. Full closed-loop control involves sending movement commands through the CNC machine tool's servo motor, and using the motor's built-in encoder to provide position feedback, which is semi-closed-loop control. Using a synchronized ruler implements full closed-loop control of the movement position. The synchronized ruler can be used as a ruler. Semi-closed-loop movement is a theoretical value, while full closed-loop control uses the synchronized ruler to provide feedback on the actual value, which is then fed back through the synchronized ruler 9. The entire process is closed-loop control, which provides high precision. By installing a synchronized ruler 9 on a machine tool, the overall accuracy of the machine tool can be greatly improved, meeting the customer's machining accuracy requirements.

[0056] The value fed back by the encoder is a theoretical value, which is moved by the motor pulse command. For example, the command moves X100, and the motor moves the theoretical value 100 through calculation. Whether the actual movement is 100 is not fed back in the semi-closed loop control, while the synchronous ruler 9 is the actual movement value fed back to achieve full closed loop control.

[0057] In the utility model, the entire material of the testing machine is made of stainless iron.

[0058] The structure includes: a servo motor 1, a base 15, a coupling 2, a screw rod 4, a linear rail 3, a slider 8, a synchronous scale mounting bracket 10, a slider mounting bracket 7, etc.

[0059] A test machine for a CNC machine tool using full closed-loop control and a Nidec synchronous ruler 9 communicating with the CNC system includes a servo motor 1 installed on the right side plate 5 (of course, it can also be installed on the left side plate 11), the servo motor 1 is connected to the coupling 2, the coupling 6 is connected to the bracket 6, the bracket 6 plays a fixed support role, and the bracket 6 is installed on the base 12. The screw 4 passes through the bracket 6 and is mounted on the bracket 6 through a bearing sleeve. The function of the screw 4 is to rotate the servo motor 1 and drive the slider 8 to run together, changing the rotational operation to linear operation. The slider mounting bracket 7 is used to install the synchronous motion slider 8. The slider 8 moves along the linear rail 3. The synchronous ruler 9 is installed on the synchronous ruler mounting bracket 10. The spacing tolerance between the synchronous ruler 9 and the slider 8 is 0.25mm±0.13mm. The left side plate 11, the right side plate 5 and the bottom plate 12 are the main supporting components of the test machine.

[0060] The installation tolerance of the synchronization ruler 9 and the slider 8 is: the spacing tolerance between the synchronization ruler and the slider. The slider is the reading head. The slider 8 and the synchronization ruler 9 are non-contact installed, and the installation tolerance is 0.25mm±0.13mm.

[0061] The present utility model, the undescribed parts are prior art.

[0062] The above are only preferred specific implementation methods of the present invention, but the protection scope of the present invention is not limited to them. Any technician familiar with the technical field can make equivalent replacements or changes based on the technical solution and utility model concept of the present invention within the technical scope disclosed by the present invention, and they should be covered by the protection scope of the present invention.

Claims

1. A fully closed-loop control testing machine for CNC machine tools that is easy to install, characterized in that: include: A base (15), wherein a servo motor (1) is mounted on one side of the base (15); A screw rod (4), the screw rod (4) being rotatably mounted on a base (15); A linear rail (3), wherein the linear rail (3) is mounted on a base (15); A slider (8), wherein the slider (8) is sleeved on the screw rod (4); The servo motor (1) drives the screw rod (4) to rotate, so that the screw rod (4) drives the slider (8) to slide on the linear rail (3), thereby achieving movement on the screw rod (4); The base (15) is provided with a structure for eliminating mechanical errors caused by thermal expansion of the screw rod (4) when the slider (8) moves on the screw rod (4).

2. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 1, characterized in that: The base (15) comprises a pedestal (12) and a left side plate (11) and a right side plate (5) respectively mounted on both ends of the pedestal (12).

3. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 2, characterized in that: The servo motor (1) is mounted on the right side plate (5) / left side plate (11) and is connected to one end of the screw rod (4) via a coupling (2).

4. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 3, characterized in that: A bracket (6) is installed on the base (12), the other end of the screw rod (4) passes through the bracket (6) and is rotatably connected to the left side plate (11) / right side plate (5), and the coupling (2) is installed on the bracket (6).

5. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 2, characterized in that: The structure comprises a synchronous ruler (9), the synchronous ruler (9) is located on a base (12), the slider (8) is mounted with a slider mounting bracket (7), and the slider mounting bracket (7) slides on the synchronous ruler (9).

6. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 5, characterized in that: A synchronous ruler mounting bracket (10) for fixing the synchronous ruler (9) is mounted on the base (12).

7. A fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 5 or 6, characterized in that: The expansion coefficient of the material of the synchronous ruler (9) is the same as the expansion coefficient of the machine tool casting of the numerical control machine tool.

8. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 6, characterized in that: The spacing tolerance between the synchronization ruler (9) and the slider (8) is 0.25 mm ± 0.13 mm.

9. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 2, characterized in that: A guide rod (13) for the slider (8) to slide is installed between the left side plate (11) and the right side plate (5).

10. The fully closed-loop controlled testing machine for CNC machine tools that is easy to install according to claim 1, characterized in that: Handles (14) are installed at both ends of the base (15).

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