The Working Principle of Planar Grinder and Its Defects

Working principle of surface Grinder

Among the existing surface Grinders, the planetary motion surface Grinder is a type of surface Grinder widely used. Planetary motion surface grinding machine, the workpiece rotates around its own axis while rotating relative to the grinding tool , that is, planetary motion, as shown in Figure 1. The grinding disc of the plane Grinder shown in Figure 1a rotates around a fixed axis, and the workpiece also rotates around its own fixed axis . This type of Grinder can have a high grinding speed, but it cannot satisfy the best kinematic conditions for grinding . Figure 1b is a schematic diagram of a planetary wheel grinding machine. The center internal gear 1 is fixed, the center gear 2 rotates around a fixed axis, and the planetary wheel 3 makes planetary motion , and drives the workpiece 4 to make planetary motion. If the workpiece does not move relative to the planetary wheel, the workpiece The motion trajectory of each point relative to the grinding disc is an epicycloid or hypocycloid (Fig. 2a, b). This type of plane grinding machine can better meet the kinematic conditions of grinding. The workpiece wear marks are not single, but the workpiece has different The movement trajectory and speed of the point relative to the grinding disc cannot be guaranteed to be completely consistent, so the grinding still has inhomogeneity, and the grinding speed is usually not very high. The planetary wheel grinding machine shown in Figure 1b usually does not clamp the workpiece, but moves against the inner wall of the planetary wheel 3 hole under the action of friction, so the workpiece has accompanied by floating grinding. Floating grinding [1] means that among the grinding tool and the workpiece, one is actively rotating, and its motion is known, while the other is floating on it, driven by the grinding and cutting force to rotate accordingly (so it is called floating), whose motion is unknown. The law of floating motion in grinding is difficult to determine and is the root cause of indeterminate wear of abrasive tools.