Linear guide rail, also known as slide rail, linear guide rail or linear slide rail, is a mechanical component used to support and guide moving parts to perform reciprocating motion in a straight direction. It plays a crucial role in modern industrial automation and precision machinery, and is widely used in automation equipment, CNC machine tools, medical machinery, and other devices that require high motion accuracy.

characteristic

High precision: Through precise machining processes and material selection, the motion is ensured to have extremely high precision, suitable for equipment that requires high-precision positioning and motion, such as CNC machine tools, precision measuring instruments, etc.

High load-bearing capacity: Made of high-strength materials and optimized design, it can withstand large loads and is suitable for heavy-duty applications such as automated production lines and heavy machinery.

Low friction: The surface has been precision treated to have low friction characteristics, reducing energy loss during motion and improving the operational efficiency of the equipment.

Long lifespan: Made of high-quality materials and advanced manufacturing processes, it has high wear resistance and fatigue resistance, which can extend its service life.

Compact structure: small in size, light in weight, easy to install and maintain, suitable for various space limited application scenarios.

type

Classified by type of motion pair: ball guide, roller guide, sliding guide, etc.

Classified by installation location: side mounted guide rail, bottom mounted guide rail, etc.

Classified by accuracy level: ordinary grade guide rail, high-precision grade guide rail, etc.

role

    The function of linear guide motion is to support and guide moving parts to perform reciprocating linear motion in a given direction. According to the friction properties, linear motion guides can be divided into sliding friction guides, rolling friction guides, elastic friction guides, fluid friction guides, and other types. Linear bearings are mainly used in automation machinery, such as machine tools, bending machines, laser welding machines, etc. imported from Germany. Of course, linear bearings and linear shafts are used in conjunction. Linear guides are mainly used in mechanical structures with high precision requirements. There is no intermediate medium between the moving and fixed components of linear guides, but rolling steel balls are used.

Automatic centering ability

    The DF (45- ° 45) ° combination from the circular arc groove, during installation, is absorbed by the interior of the track slider due to the elastic deformation of the steel ball and the transfer of the contact point. Even if there is some deviation in the installation surface, it can produce the effect of automatic centering ability and achieve high-precision and stable smooth motion.

Interchangeability

    Due to strict control over production and manufacturing accuracy, the dimensions of linear guides can be maintained within a certain level, and the slider is designed with retainers to prevent steel balls from falling off. Therefore, some series of precision are interchangeable, and customers can order guides or sliders as needed, or store them separately to reduce storage space.

High rigidity in all directions

    By using a four column circular arc groove and a 45 degree contact angle with four columns of steel balls, the steel balls achieve an ideal two-point contact structure that can withstand loads from up and down and left and right directions; When necessary, preloading can be applied to improve rigidity.

Working principle

    It can be understood as a type of rolling guidance, which is an infinite rolling cycle of steel balls between the slider and the guide rail, so that the load platform can easily move linearly with high precision along the guide rail, and the friction coefficient can be reduced to one fiftieth of that of traditional sliding guidance, which can easily achieve high positioning accuracy. The final unit design between the slider and the guide rail enables the linear guide rail to simultaneously bear loads in all directions, including up, down, left, and right. The patented reflux system and simplified structural design enable HIWIN's linear guide rail to move more smoothly and with lower noise.

    Sliding block - converts motion from a curve to a straight line. The new guide rail system enables the machine tool to achieve fast feed speed, which is a characteristic of linear guides when the spindle speed is the same. Linear guides, like flat guides, have two basic components; One serves as a fixed component as a guide, and the other is a moving component. Due to the fact that linear guides are standard components, for machine tool manufacturers, the only thing they need to do is to process a plane for installing the guide rails and adjust the parallelism of the guide rails. Of course, in order to ensure the accuracy of the machine tool, a small amount of scraping and grinding on the bed or column is essential, and in most cases, installation is relatively simple. The guide rail used as a guide is made of hardened steel and is finely ground before being placed on the installation plane. Compared with flat guide rails, the geometric shape of the cross-section of linear guide rails is more complex. The reason for the complexity is that grooves need to be machined on the guide rails to facilitate the movement of sliding components. The shape and number of grooves depend on the function that the machine tool needs to complete. For example, a guide rail system that can withstand both linear forces and overturning moments has significant differences in design compared to a guide rail that can only withstand linear forces.

    The basic function of the fixed component (guide rail) of the linear guide system is like a bearing ring, a bracket for installing steel balls, and has a "v" shape. The bracket wraps around the top and two sides of the guide rail. In order to support the working components of the machine tool, a set of linear guides has at least four brackets. Used to support large working components, the number of brackets can exceed four.

    When the working parts of the machine tool move, the steel balls circulate in the groove of the support, distributing the wear of the support to each steel ball, thereby extending the service life of the linear guide rail. In order to eliminate the gap between the bracket and the guide rail, preloading can improve the stability of the guide rail system. The preloading is achieved by installing oversized steel balls between the guide rail and the bracket. The diameter tolerance of the steel ball is ± 20 microns, with increments of 0.5 microns. The steel balls are sorted and installed on the guide rail separately. The size of the preload depends on the force acting on the steel ball. If the force acting on the steel ball is too large and subjected to preloading for too long, resulting in increased resistance to the movement of the bracket, a balance problem will occur; In order to improve the sensitivity of the system and reduce motion resistance, it is necessary to correspondingly reduce Preloading, in order to improve motion accuracy and accuracy retention, requires sufficient preload negative numbers, which are contradictory aspects.

    If the working time is too long, the steel balls begin to wear out, and the preload acting on the steel balls begins to weaken, resulting in a decrease in the precision of the machine tool's working parts. If you want to maintain the initial accuracy, you must replace the guide rail bracket, or even replace the guide rail. If the guide rail system has already been preloaded. The system accuracy has been lost, the only way is to replace the rolling elements.

    The design of the guide rail system aims to maximize the contact area between the fixed and moving components. This not only improves the system's load-bearing capacity, but also enables it to withstand the impact force generated by intermittent or gravity cutting, spreading the force widely and expanding the load-bearing area. In order to achieve this, there are various groove shapes for the guide rail system, with two representative ones. One is called Gothic (pointed arch), which is an extension of a semicircle with the contact point as the vertex; Another type is circular arc shape, which can also serve the same purpose. Regardless of the structural form, the goal is only one, to strive for more rolling steel ball radius to contact the guide rail (fixed element). The factor that determines the performance characteristics of the system is how the rolling elements contact the guide rail, which is the key to the problem.

application area

1. Linear guides are mainly used in automation machinery, such as machine tools imported from Germany, bending machines, laser welding machines, etc. Of course, linear guides and linear axes are used in conjunction.

2. Linear guides are mainly used in mechanical structures with high precision requirements. There is no intermediate medium between the moving and fixed components of linear guides, but rolling steel balls are used. Because rolling steel balls are suitable for high-speed motion, have low friction coefficients, and high sensitivity, they meet the working requirements of moving parts such as tool holders and drag plates in machine tools. If the force acting on the steel ball is too large, the steel ball will withstand the preload for too long, resulting in an increase in the resistance of the bracket movement.

Precautions for use

    Linear guides are precision components, so a considerable degree of caution is required when using them. Even if high-performance linear guides are used improperly, they cannot achieve the expected performance effect and are prone to damage. So, when using linear guides, the following precautions should be taken:

Prevent rusting

    When directly taking the linear guide rail by hand, it is necessary to thoroughly wash off the sweat on the hands and apply high-quality mineral oil before operation. Special attention should be paid to rust prevention during the rainy season and summer.

Keep the environment clean

    Keep the linear guide and its surrounding environment clean. Even tiny dust that cannot be seen by the naked eye entering the guide will increase its wear, vibration, and noise.

Installation should be done carefully and meticulously

    Linear guides should be carefully installed and used, and strong stamping is not allowed. It is not allowed to directly strike the guide rail with a hammer, and pressure transmission through rolling elements is not allowed.

The installation tool should be suitable

    Use appropriate and accurate installation tools for linear guides, and try to use specialized tools as much as possible, avoiding the use of fabrics and short fibers.

Clean the guide rail

    As one of the core components of the equipment, the guide rail and linear axis play a role in guiding and supporting. In order to ensure high machining accuracy of the machine, it is required that its guide rails and straight lines have high guiding accuracy and good motion stability. During the operation of the equipment, a large amount of corrosive dust and smoke will be generated during the processing of the workpiece. These smoke and dust will accumulate on the surface of the guide rail and linear axis for a long time, which has a great impact on the machining accuracy of the equipment and will form corrosion points on the surface of the guide rail and linear axis, shortening the service life of the equipment. In order to ensure the normal and stable operation of the machine and the processing quality of the product, it is necessary to carefully carry out daily maintenance of the guide rails and linear axes. Attention: Please prepare dry cotton cloth and lubricating oil for cleaning the guide rail. The guide rails of the engraving machine are divided into linear guide rails and roller guide rails. Cleaning of linear guide: First, move the laser head to the far right (or left), find the linear guide, wipe it with a dry cotton cloth until it is shiny and dust-free, and then add a little lubricating oil (sewing machine oil can be used, do not use machine oil). Slowly push the laser head left and right a few times to evenly distribute the lubricating oil. Cleaning of roller guide rail: Move the crossbeam to the inside, open the end covers on both sides of the machine, find the guide rail, use a dry cotton cloth to wipe clean the contact area between the two side guides and the roller, and then move the crossbeam to clean the remaining area.

Development Overview

    The sustained and rapid growth of the Chinese economy has provided a huge market space for linear guide products. The strong appeal of the Chinese market has attracted the world's attention to the Chinese market. In the short decades of reform and opening up, the enormous production capacity formed by China's linear guide manufacturing industry has impressed the world. With the continuous expansion of China's power industry, data communication industry, urban rail transit industry, automotive industry, and shipbuilding industry, the demand for linear guides will also grow rapidly, and there is still huge development potential for the linear guide industry in the future.

Installation and maintenance

Installation: Clean the base surface, pre position the guide rail, adjust the straightness, tighten the screws in sequence, and maintain the height consistency and parallelism of the dual track system.

Maintenance: Regularly wipe the guide rail and slider, apply lubricating grease, check the operating status, and avoid exposure to harsh environments.

Linear guides play an important role in modern industrial automation and precision machinery due to their high precision, long lifespan, and stability. Through reasonable selection, standardized installation, and regular maintenance, equipment operation efficiency and reliability can be significantly improved.