CN101024270A - Numerical-control machine tool magnetic suspension linear feeding system - Google Patents

Abstract

Translated fromChinese

一种新型数控机床磁悬浮直线进给系统，主要包括机座(1)、固定于其上的两条导轨(16)、直线电机定子部件(17)、(18)、安装在工作台(5)底部四个角的4对差动悬浮电磁铁(4)、(10)、安装在悬浮电磁铁(4)旁边的2对导向电磁铁(11)、安装在工作台(5)下面的直线电机动子部件(8)、(15)、(16)、安装在导轨上的光栅测量系统(6)、(7)以及支撑装置(9)。本发明的控制系统为采用DSP主控制器的悬浮电磁铁(4)、(10)和导向电磁铁(11)与导轨(16)之间的间隙控制系统以及直线电机伺服控制系统。本发明实现了机床工作台的无接触支撑与导向，消除了摩擦磨损，提高了进给速度与定位精度，并且提供了足够的承载力和推力，可用于实际加工。

A new type of magnetic levitation linear feed system for CNC machine tools, mainly including a machine base (1), two guide rails (16) fixed on it, linear motor stator components (17), (18), installed on a workbench (5) 4 pairs of differential suspension electromagnets (4), (10) at the four corners of the bottom, 2 pairs of guide electromagnets (11) installed next to the suspension electromagnet (4), and linear electromagnets installed under the workbench (5). Motorized sub-assemblies (8), (15), (16), grating measurement systems (6), (7) mounted on guide rails and support devices (9). The control system of the present invention is a suspension electromagnet (4), (10) and a gap control system between the guide electromagnet (11) and the guide rail (16) and a linear motor servo control system using a DSP main controller. The invention realizes non-contact support and guidance of the machine tool table, eliminates friction and wear, improves feed speed and positioning accuracy, and provides sufficient bearing capacity and thrust, which can be used for actual processing.

Description

Translated fromChinese

数控机床磁浮直线进给系统Magnetic levitation linear feed system for CNC machine tools

技术领域technical field

本发明涉及一种数控机床进给系统，采用磁力支撑与导向，直线电机驱动，可实现机床工作台的高速度、高加速度、高精度的无摩擦进给。The invention relates to a feeding system of a numerically controlled machine tool, which is supported and guided by a magnetic force and driven by a linear motor, and can realize high-speed, high-acceleration, and high-precision frictionless feeding of a machine tool workbench.

背景技术Background technique

传统的机床进给系统包含许多中间传动环节，整个系统的惯性质量较大，系统的动态性能较差。而且中间环节在运动过程中产生的弹性变形、摩擦磨损以及反向间隙等，会造成定位进给运动的滞后和非线性误差，影响加工精度。此外，丝杠传动的固有缺陷使工作台难以达到很高进给速度和精度。The traditional machine tool feed system contains many intermediate transmission links, the inertial mass of the whole system is large, and the dynamic performance of the system is poor. Moreover, the elastic deformation, friction and wear, and backlash of the intermediate link during the movement will cause hysteresis and nonlinear errors in the positioning and feeding movement, which will affect the machining accuracy. In addition, the inherent defects of the screw drive make it difficult for the table to achieve high feed speed and accuracy.

为了提高机床工作台的进给速度、加速度和定位精度，以直线电机代替“旋转电机+丝杠”驱动工作台的机床进给系统出现了，它的应用取消了原动力和工作台部件之间的所有中间传动联结环节，简化了系统的结构，实现了机构直接驱动。In order to improve the feed speed, acceleration and positioning accuracy of the machine tool workbench, a machine tool feed system that uses a linear motor instead of a "rotary motor + lead screw" to drive the workbench appeared. Its application cancels the gap between the original force and the workbench components. All the intermediate transmission links simplify the structure of the system and realize the direct drive of the mechanism.

与传统机械直线导轨相比，目前导轨支撑方式中的滚动导轨、塑料滑动导轨虽然摩擦系数小且耐磨性高，但在高速重载下仍会磨损；液体静压导轨处于纯液体磨擦状态，故导轨不会磨损，精度保持性好，磨擦系数小，但油污严重，结构复杂，成本高；气体静压导轨与液体静压导轨一样，需要诸多辅助设备，如：空气压缩机、蓄压器、过滤减压阀、气压传动和控制部件等，而且气体悬浮的刚度性能较差。Compared with traditional mechanical linear guides, although the rolling guides and plastic sliding guides in the current guide rail support mode have a small friction coefficient and high wear resistance, they will still wear under high-speed and heavy loads; hydrostatic guides are in a pure liquid friction state, Therefore, the guide rail will not wear out, has good precision retention and small friction coefficient, but the oil pollution is serious, the structure is complicated, and the cost is high; the gas static pressure guide rail, like the liquid static pressure guide rail, requires many auxiliary equipment, such as: air compressor, pressure accumulator , filter pressure reducing valve, pneumatic transmission and control components, etc., and the stiffness of the gas suspension is poor.

为了克服上述缺点，满足日益高速化的加工要求，本发明采用了磁浮导轨的结构。该导轨不但具有无摩擦、无润滑、精度高等特点，而且不需要任何辅助设备。此外，磁浮导轨的刚度性能好，适合重载加工。In order to overcome the above disadvantages and meet the increasingly high-speed processing requirements, the present invention adopts the structure of the magnetic levitation guide rail. The guide rail not only has the characteristics of no friction, no lubrication, high precision, etc., but also does not need any auxiliary equipment. In addition, the rigidity performance of the magnetic levitation guideway is good, which is suitable for heavy-duty processing.

目前，磁悬浮支撑与导向配合直线电机驱动的进给机构，都存在着承载能力低、驱动力小等缺点，未能真正取代现有机床进给系统。例如孙宝玉等人在文献《直线驱动磁悬浮进给机构的研究》中提出了一种结构，如附图5所示，该磁悬浮直线进给机构只用两个电磁铁提供悬浮力和导向力，垂直和横向承载能力低，而且难以满足机床加工对工作台上表面的平面度要求。所以迫切需要开发有足够承载力和推力的，可应用于实际加工的磁悬浮直线进给系统。At present, the feed mechanism driven by magnetic levitation support and guide combined with linear motor has the disadvantages of low load capacity and small driving force, and cannot really replace the existing machine tool feed system. For example, Sun Baoyu and others proposed a structure in the document "Research on Linear Drive Magnetic Suspension Feed Mechanism". As shown in Figure 5, the magnetic levitation linear feed mechanism only uses two electromagnets to provide levitation force and guiding force. The vertical and lateral bearing capacity is low, and it is difficult to meet the flatness requirements of the machine tool processing on the upper surface of the workbench. Therefore, it is urgent to develop a magnetic levitation linear feed system with sufficient bearing capacity and thrust that can be applied to actual processing.

中国科学院长春光学精密机械与物理研究所在专利文献CN1214892C中公开了一种超精密微位移导轨磁悬浮方法及其装置，但该专利只用两个电磁铁产生悬浮力，所以移动平台沿横向的转动自由度没有限制，从而变得不稳定；该专利中，用以产生悬浮力的两个电磁铁同时也起到导向的作用，必须进行解耦控制，增加了控制系统的复杂程度；该专利所用的直线电机为单边定子结构，直线电机定子和动子之间存在单边磁拉力，这给移动平台造成很大负担。The Changchun Institute of Optics, Fine Mechanics and Physics of the Chinese Academy of Sciences discloses an ultra-precision micro-displacement guide rail magnetic levitation method and its device in the patent document CN1214892C. The degree of freedom is not limited, so it becomes unstable; in this patent, the two electromagnets used to generate the levitation force also play a guiding role, and decoupling control must be performed, which increases the complexity of the control system; the patent used The linear motor has a unilateral stator structure, and there is a unilateral magnetic pull between the linear motor stator and the mover, which causes a great burden on the mobile platform.

上海大学在专利文献CN1244432C中公开了一种工业应用型主动磁悬浮导轨直线电机进给平台，但该专利中的固定部件为一两端支撑的简支梁结构，刚度性能差，容易变形，承载能力较差；该专利中的直线电机为双边动子结构，且双边动子都固定在移动部件上，这就增加了移动部件的无用重量。Shanghai University discloses an industrial application type active magnetic levitation guide rail linear motor feed platform in patent document CN1244432C, but the fixed part in this patent is a simply supported beam structure supported at both ends, which has poor rigidity performance, is easy to deform, and has low load-carrying capacity. Poor; the linear motor in this patent is a double-sided mover structure, and the double-sided movers are all fixed on the moving parts, which increases the useless weight of the moving parts.

发明内容Contents of the invention

本发明的目的就是要提供一种新型数控机床进给系统，该系统无摩擦、无润滑、无污染且可提供足够承载力和推力，以满足数控机床工作台日益增长的高速度、高加速度及高精度运行要求。The purpose of this invention is to provide a new type of CNC machine tool feed system, which has no friction, no lubrication, no pollution and can provide sufficient bearing capacity and thrust to meet the increasing high speed, high acceleration and High precision operation requirements.

本发明的另一个目的就是针对现有技术中的诸多缺陷，寻求一个更为满意的解决方案。Another object of the present invention is to seek a more satisfactory solution to many defects in the prior art.

为实现上述目的，本发明将磁悬浮支撑和直线电机驱动技术融为一体，消除了工作台和导轨之间的摩擦，实现了机床工作台的无接触支撑和导向，摒弃了传统机床进给系统的中间传动环节，实现了机床工作台的零传动。In order to achieve the above purpose, the present invention integrates magnetic levitation support and linear motor drive technology, eliminates the friction between the workbench and the guide rail, realizes the non-contact support and guidance of the machine tool workbench, and abandons the traditional machine tool feed system. The intermediate transmission link realizes the zero transmission of the machine tool table.

本发明采用如下技术方案：The present invention adopts following technical scheme:

一种数控机床磁浮直线进给系统，在结构上可分为定部件和动部件。定部件包括基座、两条导轨、光栅尺以及直线电机定子部件。动部件主要包括：工作台、四个支撑装置、四组差动悬浮电磁铁、两组导向电磁铁、八个电涡流位移传感器、直线电机动子部件、光栅读数头以及四个支撑装置。各部件的安装位置为：两条导轨对称地固定在基座上，光栅尺通过一辅助件安装在导轨上，以便重复利用；四组差动悬浮电磁铁分布于工作台的四个角的下方，每组电磁铁由上下两个电磁铁组成；两组导向电磁铁安装在悬浮电磁铁的旁边，且每组的两个电磁铁沿水平向正对安装；四个支撑装置也分别固定在工作台靠近四个角位置的下方，其水平向位置在导轨上的光栅测量系统、和悬浮电磁铁之间；用于检测悬浮间隙的四个电涡流位移传感器分别通过辅助件竖直安装在四个下悬浮电磁铁的旁边10毫米处，用于检测导向间隙的四个电涡流位移传感器分别通过辅助件沿水平向两两正对安装在四个导向电磁铁的旁边10毫米处，在电磁铁和传感器之间留出10毫米间隙是为了避免电磁铁的磁场对传感器造成影响。A magnetic levitation linear feed system for a numerical control machine tool can be divided into a fixed part and a moving part in structure. The fixed parts include a base, two guide rails, a grating ruler and a linear motor stator part. The moving parts mainly include: workbench, four supporting devices, four sets of differential levitation electromagnets, two sets of guiding electromagnets, eight eddy current displacement sensors, linear motor moving parts, grating reading head and four supporting devices. The installation position of each component is: two guide rails are symmetrically fixed on the base, and the grating ruler is installed on the guide rail through an auxiliary part for repeated use; four sets of differential suspension electromagnets are distributed under the four corners of the workbench , each group of electromagnets is composed of two upper and lower electromagnets; two groups of guiding electromagnets are installed next to the suspension electromagnets, and the two electromagnets of each group are installed facing each other along the horizontal direction; the four support devices are also fixed on the working The table is close to the bottom of the four corner positions, and its horizontal position is between the grating measurement system on the guide rail and the suspension electromagnet; the four eddy current displacement sensors used to detect the suspension gap are installed vertically on the four sides through auxiliary parts. At 10 mm next to the lower suspension electromagnet, four eddy current displacement sensors used to detect the guide gap are respectively installed in pairs at 10 mm next to the four guide electromagnets through auxiliary parts along the horizontal direction. A gap of 10 mm is left between the sensors to avoid the influence of the magnetic field of the electromagnet on the sensors.

上述的数控机床磁浮直线进给系统各部件的具体作用为：悬浮电磁铁承载含工件、工作台、直线电机动子部件、悬浮电磁铁和导向电磁铁及其联接元件的自重以及垂直切削力在内的所有垂直方向的载荷；导向电磁铁控制横向间隙，消除切削力及其他不确定因素引起的进给部件的横向扰动，保证工作台的纵向精确进给；直线电机实现工作台的纵向进给；支撑装置可在故障、停机和突然断电时起到横向和垂直支撑的作用。此外，不锈钢板机床导轨防护罩(图中未画出)可起到防屑和隔磁的作用。The specific functions of the various components of the above-mentioned maglev linear feed system for CNC machine tools are as follows: the suspension electromagnet carries the self-weight of the workpiece, worktable, linear motor mover components, suspension electromagnet, guide electromagnet and their connecting components, and the vertical cutting force. All the loads in the vertical direction; the guiding electromagnet controls the lateral gap, eliminates the lateral disturbance of the feeding parts caused by the cutting force and other uncertain factors, and ensures the longitudinal and precise feeding of the table; the linear motor realizes the longitudinal feeding of the table ; The support device can play the role of horizontal and vertical support in case of failure, shutdown and sudden power failure. In addition, the stainless steel plate machine guide rail guard (not shown in the figure) can play the role of chip prevention and magnetic isolation.

上述的数控机床磁浮直线进给系统的悬浮和导向电磁铁都通过支架固定在工作台上，各电磁铁和支架之间通过过盈配合连接，支架用铝基复合材料制成。悬浮电磁铁和导向电磁铁的各参数都进行了标准化、最优化，在实际操作中，只要工作台尺寸允许，可将导向和悬浮电磁铁沿工作台的纵向多个排列，以提高垂直和横向承载能力。此外，本数控机床磁浮直线进给系统的支撑装置与导轨之间的横向、垂直间隙，分别小于导向电磁铁、悬浮电磁铁和导轨之间的间隙，所以支撑装置可在非工作状态、突然断电或故障停机的情况下起到垂直和横向支撑的作用。The levitation and guide electromagnets of the above-mentioned maglev linear feed system of the numerical control machine tool are fixed on the workbench through brackets, and the electromagnets and brackets are connected by interference fit, and the brackets are made of aluminum matrix composite materials. The parameters of the suspension electromagnet and the guide electromagnet have been standardized and optimized. In actual operation, as long as the size of the workbench allows, the guide and suspension electromagnets can be arranged in multiple longitudinal directions along the workbench to improve the vertical and horizontal Carrying capacity. In addition, the horizontal and vertical gaps between the support device and the guide rail of the maglev linear feed system of the CNC machine tool are respectively smaller than the gaps between the guide electromagnet, the suspension electromagnet and the guide rail, so the support device can be disconnected suddenly in a non-working state. It plays the role of vertical and lateral support in case of power failure or failure.

本发明数控机床磁浮直线进给系统给出了一种实现机床工作台无接触支撑和导向的方法：在工作台四个角的下方布置四组差动控制的悬浮电磁铁，每组悬浮电磁铁由上下两个电磁铁组成，装在下悬浮电磁铁旁边的电涡流位移传感器实时检测电磁铁和导轨之间的间隙，并经A/D转换装置和电平匹配电路将间隙量以电流信号的形式送给数字DSP控制器，DSP经运算后将差动控制信号经D/A转换和驱动器送给悬浮电磁铁线圈绕组，以调节电磁铁和导轨之间间隙，从而实现工作台在垂直方向上的稳定悬浮。四组悬浮电磁铁的解耦控制通过软件实现，它们共约束工作台三个自由度：沿垂直方向的移动、绕纵向的转动和绕横向的转动。四个导向电磁铁安装在工作台四个角下方的悬浮电磁铁旁边，其工作原理与悬浮电磁铁是相同的，不同的是四个导向电磁铁分成两组工作，而且每组电磁铁沿横向正对安装，便于实现差动控制，导向电磁铁共约束工作台两个自由度：沿横向的移动和绕竖直方向的转动。The magnetic levitation linear feed system of the numerical control machine tool of the present invention provides a method to realize the non-contact support and guidance of the machine tool workbench: four sets of differentially controlled levitation electromagnets are arranged under the four corners of the workbench, and each set of levitation electromagnets It is composed of upper and lower electromagnets. The eddy current displacement sensor installed next to the lower suspension electromagnet detects the gap between the electromagnet and the guide rail in real time, and converts the gap amount in the form of a current signal through the A/D conversion device and the level matching circuit. Send it to the digital DSP controller. After the DSP is calculated, the differential control signal is sent to the coil winding of the suspension electromagnet through D/A conversion and the driver to adjust the gap between the electromagnet and the guide rail, so as to realize the vertical movement of the workbench. Stable suspension. The decoupling control of the four sets of levitating electromagnets is realized by software, and they constrain the three degrees of freedom of the worktable: vertical movement, longitudinal rotation and lateral rotation. The four guide electromagnets are installed next to the suspension electromagnets under the four corners of the workbench. Its working principle is the same as that of the suspension electromagnets. Directly facing installation facilitates differential control. The guide electromagnet constrains the two degrees of freedom of the worktable: lateral movement and vertical rotation.

上述的数控机床磁浮直线进给系统的直流直线电机的定子部件主要包括永磁体和永磁体磁轭，动子部件包括绕组、绕组支架以及导磁体。其中永磁体采用若干小块NdFeB永磁体沿纵向连续排列而成，永磁体磁轭采用#20钢。动子绕组采用铝导线绕制而成，绕组支架采用铝基复合材料制成，这都是为了减轻动子的重量。动子导磁体采用Ni-Zn软磁铁氧体制成，这是为了在保证较好的导磁性能的前提下，尽量提高其电阻率，以减少电机运行时由于反向感应电动势引起的感应电流，从而减少反向电磁力，动子导磁体通过燕尾槽结构和绕组支架连接在一起。该直流直线电机的控制系统主要包括DSP主控制器、光电隔离电路、A/D及D/A装换装置、霍尔电流传感器、光栅检测系统以及H型桥式斩波驱动器，控制系统的电流逆变功能由驱动器完成，直线电机的位置及速度调节都由软件实现。此外，直线电机的定子和动子基本呈水平向布置。The stator part of the DC linear motor of the above-mentioned maglev linear feed system for a numerically controlled machine tool mainly includes a permanent magnet and a permanent magnet yoke, and the mover part includes a winding, a winding support and a magnetizer. Among them, the permanent magnet is made of several small pieces of NdFeB permanent magnets arranged continuously in the longitudinal direction, and the permanent magnet yoke is made of #20 steel. The mover winding is made of aluminum wire, and the winding bracket is made of aluminum matrix composite material, which is to reduce the weight of the mover. The mover magnet is made of Ni-Zn soft magnetic ferrite, which is to increase its resistivity as much as possible under the premise of ensuring better magnetic permeability, so as to reduce the induced current caused by the reverse induced electromotive force when the motor is running. In order to reduce the reverse electromagnetic force, the magnet conductor of the mover is connected with the winding bracket through the dovetail groove structure. The control system of the DC linear motor mainly includes DSP main controller, photoelectric isolation circuit, A/D and D/A replacement device, Hall current sensor, grating detection system and H-type bridge chopper driver, the current of the control system The inverter function is completed by the driver, and the position and speed adjustment of the linear motor are realized by software. In addition, the stator and mover of the linear motor are basically arranged horizontally.

综上所述，本发明在实现机床工作台的无接触支撑、导向和直接驱动的同时，还给出提高承载能力和驱动力的方法，使其能够应用于高速度、高加速度的数控机床的进给系统。In summary, while realizing the non-contact support, guidance and direct drive of the machine tool workbench, the present invention also provides a method for improving the bearing capacity and driving force, so that it can be applied to high-speed, high-acceleration CNC machine tools. feed system.

相对于专利文献CN1214892C来说，本发明采用了四组悬浮电磁铁来提供悬浮力，移动平台沿横向的转动自由度得到了限制，同时由于每组电磁铁都采用了差动控制，故提高了精度；另外本发明中，悬浮电磁铁和导向电磁铁的作用方向相互垂直不存在耦合现象；本发明中的直线电机采用双边定子结构，不存在单边磁拉力的问题。Compared with the patent document CN1214892C, the present invention adopts four sets of levitating electromagnets to provide levitation force, and the freedom of rotation of the moving platform along the lateral direction is restricted. In addition, in the present invention, the action directions of the suspension electromagnet and the guide electromagnet are perpendicular to each other and there is no coupling phenomenon; the linear motor in the present invention adopts a double-sided stator structure, and there is no problem of unilateral magnetic pull.

相对于专利文献CN1244432C来说，本发明中承载导轨沿纵向处处和基座接触，故刚度性能好，大大提高了承载能力；另外本发明中的直线电机采用双边定子结构，而且动子采用轻质材料，有效地减小了移动平台的自重，进而提高了承载能力和整个系统的效率。Compared with the patent document CN1244432C, in the present invention, the load-bearing guide rail is in contact with the base everywhere along the longitudinal direction, so the rigidity performance is good, and the load-carrying capacity is greatly improved; in addition, the linear motor in the present invention adopts a double-sided stator structure, and the mover adopts a lightweight materials, effectively reducing the weight of the mobile platform, thereby improving the carrying capacity and the efficiency of the entire system.

附图说明Description of drawings

附图1为数控机床磁浮直线进给系统机械结构主视示意图。Accompanying drawing 1 is the schematic diagram of the front view of the mechanical structure of the maglev linear feed system of the numerical control machine tool.

附图2为数控机床磁浮直线进给系统机械结构侧视示意图。Accompanying drawing 2 is the schematic diagram of the side view of the mechanical structure of the maglev linear feed system of the CNC machine tool.

附图3为数控机床磁浮直线进给系统机械结构俯视示意图。Accompanying drawing 3 is the top view diagram of the mechanical structure of the maglev linear feed system of the numerical control machine tool.

附图4为数控机床磁浮直线进给系统控制系统示意图。Accompanying drawing 4 is the schematic diagram of the control system of the maglev linear feed system of the CNC machine tool.

附图5为一种磁悬浮直线进给机构示意图。Accompanying drawing 5 is a schematic diagram of a magnetic levitation linear feed mechanism.

具体实施方式Detailed ways

首先，参见附图1、2、3，本发明数控机床磁浮直线进给系统，包含有基座1、固定于基座1上的两条导轨14、直线电机定子部件17、18、安装在工作台5的四个角的下方的四组差动悬浮电磁铁4、10、安装在悬浮电磁铁10旁边的两组导向电磁铁11、安装在悬浮电磁铁4、10和导向电磁铁11旁边的电涡流位移传感器19、21、安装在工作台5下面的直线电机动子部件8、15、16、安装在导轨上的光栅尺6、安装在工作台下方的光栅读数头7、安装在工作下方的支撑装置9以及导轨防护罩(图中未画出)。First, referring to accompanyingdrawings 1, 2, and 3, the maglev linear feed system for numerically controlled machine tools of the present invention includes a base 1, twoguide rails 14 fixed on the base 1, linearmotor stator components 17, 18, installed in the working Four sets ofdifferential levitation electromagnets 4 and 10 below the four corners ofplatform 5, two sets of guide electromagnets 11 installed next to thelevitation electromagnet 10, two sets of guide electromagnets 11 installed next to thelevitation electromagnets 4, 10 and guide electromagnet 11 Eddycurrent displacement sensors 19, 21, linearmotor mover components 8, 15, 16 installed under theworkbench 5, grating scale 6 installed on the guide rail, grating readinghead 7 installed under the workbench, installed under the workbench The supporting device 9 and the guide rail protective cover (not shown in the figure).

下面结合附图以本发明的一个工作周期为例作详细说明。A working cycle of the present invention will be described in detail below in conjunction with the accompanying drawings as an example.

机床进给系统未启动时，各电磁铁线圈中没有电流，所以电磁铁不产生电磁吸力，整个动平台靠支撑装置9支撑在导轨14上。由于支撑装置9与导轨14之间的横向、垂直间隙，分别小于导向电磁铁11、悬浮电磁铁4和导轨14之间的间隙，所以当整个机床进给系统未通电时，可保证支撑装置9与导轨14保持横向和垂直接触，而各电磁铁4、10、11与导轨14保持一定间隙。When the feed system of the machine tool is not started, there is no electric current in each electromagnet coil, so the electromagnet does not produce electromagnetic attraction, and the whole moving platform is supported on theguide rail 14 by the supporting device 9 . Since the horizontal and vertical gaps between the support device 9 and theguide rail 14 are respectively smaller than the gaps between the guide electromagnet 11, the suspension electromagnet 4 and theguide rail 14, when the entire machine feed system is not powered, the support device 9 can be guaranteed Keep lateral and vertical contact withguide rail 14, and eachelectromagnet 4,10,11 andguide rail 14 keep certain clearance.

系统通电后，电磁铁4、10、11产生对导轨9的垂直方向上的和横向的电磁吸力，各电涡流位移传感器19、21将检测到的电磁铁4、10、11和导轨9之间的间隙转换成电信号，该信号经A/D转换、电平转换电路等装置被送入DSP主控制器，控制器经一系列运算输出控制信号，再经过D/A转换和驱动器将控制电流加到电磁铁4、10、11的绕组3、12上，调节电磁铁4、10、11与导轨9之间的间隙，从而使动平台在很短的时间内自动找正，而以设定间隙悬浮起来，支撑装置9亦脱离导轨14，整个系统进入工作状态。After the system is energized, theelectromagnets 4, 10, 11 produce electromagnetic attraction force in the vertical direction and the transverse direction to the guide rail 9, and each eddycurrent displacement sensor 19, 21 detects the gap between theelectromagnet 4, 10, 11 and the guide rail 9. The gap is converted into an electrical signal, and the signal is sent to the DSP main controller through A/D conversion, level conversion circuit and other devices. Added to thewindings 3, 12 of theelectromagnets 4, 10, 11, to adjust the gap between theelectromagnets 4, 10, 11 and the guide rail 9, so that the moving platform can be automatically aligned in a short time, and the set The gap is suspended, the supporting device 9 is also separated from theguide rail 14, and the whole system enters the working state.

动平台稳定悬浮后，位移传感器19实时监测悬浮电磁铁4、10与导轨14之间的间隙，并将该信息反馈给控制系统，当悬浮间隙由于干扰而变化时，控制系统将差动控制电流信号分配给差动悬浮电磁铁4、10，强迫移动平台回到设定位置，通过DSP控制器的PID调节使移动平台稳定悬浮。两组导向电磁铁11的工作原理与悬浮电磁铁4、10是一样的，只不过导向电磁铁11的作用力方向沿横向，它主要是为了控制横向间隙，从而保障工作台5沿纵向精确进给。After the moving platform is suspended stably, the displacement sensor 19 monitors the gap between thesuspension electromagnets 4, 10 and theguide rail 14 in real time, and feeds the information back to the control system. When the suspension gap changes due to interference, the control system will differentially control the current The signals are distributed to thedifferential levitation electromagnets 4 and 10 to force the mobile platform to return to the set position, and the mobile platform is stably suspended through the PID adjustment of the DSP controller. The working principle of the two groups of guiding electromagnets 11 is the same as that of thesuspension electromagnets 4 and 10, except that the direction of force of the guiding electromagnets 11 is along the horizontal direction, which is mainly for controlling the lateral gap, thereby ensuring that theworkbench 5 moves vertically and accurately. Give.

当需要平台做纵向进给运动时，上位机发出速度和位置指令，由光栅检测系统6、7、A/D装置、DSP主控制器、D/A装置以及驱动器组成的直流直线电机控制回路，驱动并调节直线电机动子8、15、16以指定的速度运动到指定位置。在此过程中，光栅6、7实时检测动平台的位置和速度，控制器根据此信号以很短的时间间隔做出控制反应，这一点在动平台定位后尤为明显，实际上动平台不可能准确低定位在某一指定位置，而是在此位置附近作微小颤动，我们可以通过调节电机的PID控制参数而使该颤动控制在误差允许的范围内，最高定位精度可达微米级。此外，值得一提的是，由于本发明的驱动装置采用直流供电，所以需要电流换向装置，本系统中，换向功能是由驱动器完成的。When the platform is required to do longitudinal feed movement, the upper computer sends speed and position commands, and the DC linear motor control loop composed ofgrating detection systems 6, 7, A/D device, DSP main controller, D/A device and driver, Drive and adjust thelinear motor movers 8, 15, 16 to move to the designated position at the designated speed. During this process, thegratings 6 and 7 detect the position and speed of the moving platform in real time, and the controller makes a control response in a very short time interval according to this signal. This is especially obvious after the moving platform is positioned. In fact, it is impossible for the moving platform to Accurately locate at a specified position, but vibrate slightly near this position. We can control the vibration within the allowable range of error by adjusting the PID control parameters of the motor, and the highest positioning accuracy can reach the micron level. In addition, it is worth mentioning that since the driving device of the present invention uses DC power supply, it needs a current commutation device. In this system, the commutation function is completed by the driver.

工作完成后，先给直线电机绕组16断电，而后逐步减小各电磁铁4、10、11线圈绕组3、12的电流，使支撑装置9缓慢落在导轨14上，由于支撑装置9和导轨14之间的间隙不到0.3毫米，所以接触时，几乎没有撞击震动。After the work is finished, first give the linear motor winding 16 power-off, then gradually reduce the current of eachelectromagnet 4, 10, 11 coil winding 3, 12, so that the supporting device 9 slowly falls on theguide rail 14, because the supporting device 9 and the guide rail The gap between the 14 is less than 0.3 mm, so there is almost no impact vibration when touching.

Claims (9)

1. a numerical-control machine tool magnetic suspension linear feeding system includes limiting-members and dynamic component; Limiting-members mainly comprises pedestal (1), be fixed in guide rail (14) on the pedestal (1) and linear motor stator electric parts (17), (18); Dynamic component mainly comprises workbench (5), levitating electromagnet (4), (10), guiding electromagnet (11), bracing or strutting arrangement (9) and linear motor rotor parts (8), (15), (16); It is characterized in that: levitating electromagnet has four groups (4), (10), and is distributed in the below at four angles of workbench (5), and every group of electromagnet is made up of two electromagnet up and down, and is provided with the levitation gap control system; Guiding electromagnet (11) has four and form two groups, and two electromagnet of every group to facing installation, and are provided with the guiding clearance control system along level; The stator component of linear electric motors (17), (18) are installed on the guide rail (14), and linear motor rotor parts (8), (15), (16) are installed in workbench (5) bottom, and are provided with linear electric motors position and speed control system.

2. numerical-control machine tool magnetic suspension linear feeding system as claimed in claim 1, it is characterized in that: levitating electromagnet (4), (10) and guiding electromagnet (11) are fixed on the workbench (5) by support (2), (13), the iron core of each electromagnet adopts silicon steel plate stacking to form, and and connect by interference fit between the support (2), (13), make with aluminum matrix composite support (2), (13).

3. numerical-control machine tool magnetic suspension linear feeding system as claimed in claim 1 is characterized in that: linear motor stator electric parts (17), (18) are level to layout substantially with linear motor rotor parts (8), (15), (16).

4. as claim 1,2 or 3 described numerical-control machine tool magnetic suspension linear feeding systems, it is characterized in that: four bracing or strutting arrangements (9) also are separately fixed at workbench (5) near the below of position, four angles, its level to the position between the optical grating measuring system (6) on the guide rail (14), (7) and levitating electromagnet (10); Between bracing or strutting arrangement (9) and the guide rail (14) laterally, the down suction is respectively less than the gap between guiding electromagnet (11), levitating electromagnet (4) and the guide rail (14).

5. as claim 1,2 or 3 described numerical-control machine tool magnetic suspension linear feeding systems, it is characterized in that: bilateral structure is adopted in motor stator parts (17), (18), mainly comprises permanent magnet (17) and yoke (18); The mover component of motor (8), (15), (16) comprise coil windings (16), magnetic conductor (15) and support (8), and magnetic conductor (15) is connected by oat tail groove structure and support (8), and two coil windings (16) that pass to current in opposite are around thereon; The material of yoke (18) is the #20 steel, and the material of magnetic conductor (15) is the Ni-Zn soft magnetic ferrite, and the material of winding support (8) is an aluminum matrix composite.

6. according to claim 1,2 or 3 described numerical-control machine tool magnetic suspension linear feeding systems, it is characterized in that: described levitation gap control system comprises four eddy current displacement sensors (19) that vertically are provided with, eddy current displacement sensor (19) is installed in the next door of four low suspension electromagnet (4) by auxiliary member (20), and keeps 10 mm distance with electromagnet; Each sensor detects the gap between each electromagnet (4), (10) and the guide rail (14) in real time, and be sent to digital DSP master controller with the form of the signal of telecommunication, the control signal of dsp controller output is given the winding of each electromagnet (4), (10) through D/A conversion and power amplification, thereby realizes the control of levitation gap.

7. according to claim 1,2 or 3 described numerical-control machine tool magnetic suspension linear feeding systems, wherein the guiding clearance control system is characterised in that: the measuring system of described guiding clearance comprises the current vortex sensor (21) of two pairs of differential detection, the every pair of sensor along laterally over against the next door that is installed in guiding electromagnet (11), and keeps 10 mm distance with electromagnet by auxiliary member (22); Each sensor detects the gap between each electromagnet (11) and the guide rail (14) in real time, and be sent to digital DSP master controller with the form of the signal of telecommunication, the control signal of dsp controller output is given the winding of each electromagnet (11) through D/A conversion and power amplification, thereby realizes the control of guiding clearance.

8. according to claim 1,2 or 3 described numerical-control machine tool magnetic suspension linear feeding systems, wherein said linear electric motors position and speed control system are characterised in that: grating chi (6) is housed on the guide rail (14), grating reading head (7) is installed in the below of workbench (5), grating detection system (6), (7) Shu Chu signal is connected with the DSP master controller, linear motor rotor parts (8), (15), (16) position adjustments and speed are adjusted in the DSP and are realized by software, the control signal of DSP master controller output is through photoelectric isolating circuit, D/A conversion equipment and H type bridge-type chopper driver are given the winding (16) of DC linear electric motor, realize DC linear electric motor mover component (8), (15), (16) position and speed control.

9. method that realizes contactless support of platen and guiding: at the levitating electromagnet (4) of four groups of Differential Control of arranged beneath at (5) four angles of workbench, (10), every group of levitating electromagnet is made up of two electromagnet up and down, the eddy current displacement sensor (19) that is contained in low suspension electromagnet (10) next door detects the gap between electromagnet (10) and the guide rail (14) in real time, and give digital dsp controller with gap value with the form of current signal through A/D conversion equipment and electrical level matching circuit, DSP gives levitating electromagnet (4) with differential control signal through D/A conversion and driver after computing, (10) coil windings, with regulating magnet (4), (10) gap and between the guide rail (14), thus realize workbench (5) stable suspersion in vertical direction; The decoupling zero of four groups of levitating electromagnets (4), (10) control realizes that by software they retrain the workbench three degree of freedom altogether: moving vertically, around rotating longitudinally and around horizontal rotation; Four guiding electromagnets (11) are installed in levitating electromagnet (10) next door of below, (5) four angles of workbench, its operation principle is identical with levitating electromagnet (4), (10), different is that four guiding electromagnets (11) are divided into two groups of work, and every group of electromagnet edge is laterally over against installation, be convenient to realize Differential Control, guiding electromagnet retrains two frees degree of workbench altogether: move and around the rotation of vertical direction along horizontal.

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