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A grinder is a machine tool that uses abrasive tools to grind the surface of a workpiece.
Most grinding machines use high-speed rotating grinding wheels for grinding, and a few use other abrasive tools such as oilstone, abrasive belts, and free abrasives for processing, such as honing machines, superfinishing machine tools, belt grinding machines, grinding machines and polishing. machine etc.
The grinder can process materials with higher hardness, such as hardened steel, cemented carbide, etc.; it can also process brittle materials, such as glass and granite. The grinder can perform high-precision grinding with small surface roughness, as well as high-efficiency grinding, such as strong grinding.
In the 1830s, in order to adapt to concrete vibrator poker the hardened processing of clocks, bicycles, sewing machines and firearms, the United Kingdom, Germany and the United States developed grinding machines using natural abrasive grinding wheels. These grinders were rebuilt by adding grinding heads to the existing machine tools such as lathes and planers at that time. They have simple structures, low rigidity, and are prone to vibration during grinding. Operators are required to have high skills to grind precision. workpiece.
Automatic measuring devices began to be applied to grinding machines in 1908. Around 1920, centerless grinders, double-end grinders, roll grinders, guideway grinders, honing machines and ultra-finishing machine tools were successively made and used; in the 1950s, high-precision cylindrical grinders that could be used for mirror grinding appeared; in the 1960s At the end of the year, high-speed grinders with a grinding wheel linear speed of 60-80 m/s and surface grinders with large depth of cut and slow feed appeared; in the 1970s, technologies such as digital control and adaptive control using microprocessors were widely used on grinders. Applications.
With the increase in the number of high-precision, high-hardness mechanical parts, as well as the development of precision casting and precision forging processes, the performance, variety and output of grinding machines are constantly improving and growing.
Grinders are the most diverse type of metal cutting machine tools. The main types are cylindrical grinders, internal grinders, surface grinders, centerless grinders, and tool grinders.
Cylindrical grinders are the most widely used grinders that can process various cylindrical and conical outer surfaces and shaft shoulder end faces. The universal cylindrical grinder also has internal grinding accessories, which can grind the inner hole and the inner and outer conical surfaces with larger taper. However, the degree of automation of the cylindrical grinder is low, and it is only suitable for small and medium batch production and repair work.
The grinding wheel spindle of the internal grinding machine has a high speed, which can grind the surface of cylindrical and conical inner holes. Ordinary internal grinding machines are only suitable for single-piece and small batch production. In addition to the automatic working cycle, automatic and semi-automatic internal grinding machines can also be automatically measured during processing, and are mostly used in mass production.
The workpiece of the surface grinder is generally clamped on the worktable, or fixed on the electromagnetic worktable by electromagnetic suction, and then the periphery or end face of the grinding wheel is used to grind the plane of the workpiece; the centerless grinder usually refers to the centerless cylindrical grinder, that is, the workpiece does not use The center or chuck is centered and supported, and the grinding outer surface of the workpiece is used as the positioning surface. The workpiece is located between the grinding wheel and the guide wheel, and is supported by the pallet. This type of grinding machine has high production efficiency, is easy to realize automation, and has multiple uses. in mass production.
Tool grinder is a grinder specially used for tool manufacturing and tool sharpening.
The abrasive belt grinder uses a fast-moving abrasive belt as an abrasive tool, and the workpiece is supported by a conveyor belt. The efficiency is several times higher than other grinders, and the power consumption is only a fraction of other grinders. Difficult-to-machine materials and mass-produced flat parts, etc.
Specialized grinders are grinders that grind a certain type of parts, such as crankshafts, camshafts, splined shafts, guide rails, vanes, bearing raceways, gears and threads. In addition to the above categories, there are many types of honing machines, grinding machines, coordinate grinders and billet grinders.
