The application of linear bearings in optical equipment slide components

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The application of linear bearings in optical equipment slide components

The precision requirements for optical products are getting higher and higher, and the precision of the machining machine for optical products must also be improved. In the processing machine tools used in the optical industry, the main components of the polishing mill slide frame - bearings (linear bearings or stroke bearings) and sliding rods - require flexibility during operation, small clearance Z between them, and the longest possible service life.

The design structure of the sliding frame components is shown in the figure.

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The left part is a pendulum eccentric structure, with an adjustable eccentricity size (0 mm~26 mm), which is the input end of the power for the sliding frame movement. The right part is an iron pen structure, which is the Z-terminal execution end of the workpiece processed by the equipment. The middle part is further divided into three parts: upper, middle, and lower. The upper part is the compression structure of the cylinder, providing the pressure for the iron pen to work; The middle part is the rotating part, which transmits the rotational motion of the eccentric disc - rotation; The following is the sliding part of the entire slide, which transmits the rotational motion of the eccentric disc - movement, and is also the basic component of the entire slide, playing a supporting role.

The movement of the entire sliding frame component is driven by the pendulum shaft to make a circular motion of the eccentric disc, which then drives the sliding frame to move (a composite motion of sliding frame rotation and movement). After Z, it drives the rotation of the iron pen. The trajectory of the iron pen is an irregular closed curve composed of two circular arcs, symmetrical up and down, and asymmetrical left and right. It can also be referred to as a quasi elliptical trajectory. The improvement of surface quality in optical component machining requires the repeatability and regularity of the movement trajectory of the iron pen, which mainly depends on the flexibility of the middle part of the sliding frame, and the key to this flexibility is determined by the two sliding rods and their linear bearings that slide together.

The bearings in the slider of the sliding frame components have always been using linear bearings, which mainly serve as a guide for relative movement. The bearing support points are fixed and unchanged, and the two sliding rods slide relative to the matching linear bearings.

Linear bearings are commonly purchased components, while sliding rods are self-made components. During processing, the material, diameter, and pressure of the workpiece (optical glass) may vary, resulting in different force conditions on the sliding rod. Factors such as the length of time the equipment is turned on every day and the maintenance of the sliding frame can cause wear and affect the reliable use of the equipment. This is because the movement of linear bearings is carefully analyzed to identify the problem points.

Constant force | Linear bearing series