During the linear motor module installation process, the key prerequisite for controlling guide rail parallelism and the mounting datum is meticulous pre-treatment of the mounting datum surface to ensure that it meets required flatness and cleanliness. Protrusions, depressions, oil stains, or impurities on the mounting datum surface (such as the equipment work surface or dedicated mounting base) can directly lead to guide rail base deviation after installation, further causing parallelism issues. Therefore, it is necessary to first repair minor imperfections on the datum surface through grinding or scraping to remove surface oxides and impurities. The datum surface should then be thoroughly cleaned with cleaning tools to prevent particles from forming "support points" between the guide rail and the datum surface, which could cause uneven localized force and deformation. This ensures a smooth and clean foundation for subsequent guide rail installation, minimizing the potential for precision deviation.
Establishing a consistent and stable mounting datum is crucial for controlling precision. Guide rail positioning deviations caused by inconsistent datums must be avoided. Typically, the linear motor module's installation reference is based on the equipment's core functional datum (such as the machining platform's positioning datum line or the machine's coordinate system's datum axis). This datum line is accurately transferred to the guide rail mounting area using a laser locator or precision ruler, and clear datum markings are established. During installation, ensure that both guide rails are installed relative to the same datum, rather than using different locations as datums. This prevents the guide rails from appearing "parallel but offset" due to inconsistent datums. This offset, while seemingly parallel, increases the relative positional deviation between the linear motor's rotor and stator during operation, affecting positioning accuracy and potentially causing operational stalls due to uneven force.
Adjusting guide rail parallelism requires a step-by-step approach of "rough installation first, fine adjustment later," utilizing specialized measuring tools for precise control. During the rough assembly phase, the guide rails are initially secured to the reference surface, ensuring that they are roughly flush against it. Do not tighten all the fixing bolts yet. During the fine-tuning phase, use a dial indicator or micrometer (secured to the reference surface via a base) to slowly move the gauge along the length of the guide rails, checking the flatness and parallelism of each section. If deviation is detected in any section, fine-tune the shims at the bottom of the rails (or adjust the height of the support base). For example, if a section of the rails is higher than the reference surface, reduce the thickness of the shims at that location. If the distance between the two rails is uneven, fine-tune the lateral position of the rails until the deviation displayed by the measuring tool stabilizes within the allowable range. Then, gradually tighten the fixing bolts to avoid deformation of the rails caused by tightening all at once, which could affect the adjusted parallelism.
During the installation process, the tightening sequence and force of the guide rail fixing bolts must be strictly controlled to prevent plastic deformation of the rails due to uneven force, which could affect parallelism. Bolt tightening should follow the principles of "symmetry, step-by-step, and uniformity." Tighten sequentially from the center of the guide rail toward both ends, rather than tightening individually from one end to the other. This prevents the guide rail from bending due to excessive force on one side. A torque wrench should be used to control the tightening torque of the bolts to ensure that each bolt is tightened uniformly. This prevents overtightening of some bolts, which may cause partial dents in the guide rail, or undertightening of others, which may cause slight displacement during operation. After tightening the bolts, the guide rail's parallelism should be rechecked to confirm that there is no deviation caused by the tightening operation. This ensures that the guide rail remains structurally stable after installation.
The assembly coordination of the guide rail with the linear motor's stator and mover must be considered simultaneously to avoid indirect misalignment between components that may affect the actual guide rail parallelism. During installation, ensure that the direction of motion of the guide rail is strictly parallel to the direction of the stator's magnetic field. The connection surface between the mover and the guide rail slider must be precisely leveled. Any tilt in the connection surface will cause the mover to exert additional lateral forces on the guide rail during operation. Long-term operation will not only lead to increased wear on the guide rail but may also cause minor deformation, disrupting the originally adjusted parallelism. Therefore, the flatness of the connection surface between the mover and the slider should be checked with a feeler gauge or a precision level. If necessary, use thin adjustment shims to correct any deviations. This ensures that the force applied by the mover during operation is fully transmitted along the guide rail, eliminating additional lateral forces and avoiding operational lag or accuracy degradation due to component mismatch.
Post-installation dynamic verification and fine-tuning are crucial steps to ensure accuracy and stability; static measurement data alone cannot be relied upon. After the guide rail and motor module are installed, a no-load test run should be conducted, with the mover running at a low, constant speed along the entire length of the guide rail. Displacement sensors or laser interferometers should be used to monitor the mover's trajectory and position accuracy in real time. If any stuttering or track deviation is detected during operation, the machine should be stopped to inspect the guide rail parallelism. This could be due to slight displacement of a section of the guide rail during the test run due to vibration, or hidden loosening of the fixing bolts. In this case, the datum and parallelism should be rechecked, and minor adjustments should be made to the deviations before another test run. This ensures that the statically adjusted parallelism remains stable during dynamic operation, thus avoiding accuracy deviations during actual use.
In addition, the temperature and vibration control of the installation environment should be considered to prevent environmental factors from affecting the datum stability and guide rail parallelism. If the installation environment fluctuates significantly, the metal datum surface and guide rail will undergo dimensional changes due to thermal expansion and contraction, potentially disrupting the adjusted parallelism. Therefore, installation and adjustment should be performed in a constant temperature environment, or appropriate temperature compensation clearance should be provided during installation. If the environment is subject to continuous vibration, a vibration damper should be installed beneath the mounting base to prevent vibration-induced relative displacement between the guide rail and datum surface, or to prevent the fixing bolts from gradually loosening. By controlling environmental factors, the long-term stability of the parallelism between the mounting base and the guide rail is further guaranteed, ensuring that the linear motor module always maintains good operating condition during subsequent use, avoiding problems such as jamming and accuracy deviation.
