Gear machining machine tools are widely used in automobile, tractor, machine tool, engineering machinery, mining machinery, metallurgical machinery, petroleum, instrumentation, aircraft and spacecraft and other machinery manufacturing industries.
The gear machining machine tool processes various cylindrical gears, bevel gears and other toothed parts. There are many types of gear machining machine tools, including small machine tools that process gears with a diameter of a few millimeters, large machine tools that process gears with a diameter of more than ten meters, and high-precision machine tools that process high-precision gears with high-efficiency machine tools for mass production.
Ancient gears were shaped by hand. In 1540, when Toriano in Italy manufactured clocks, it made a gear cutting device using a rotary file; in 1783, Rene in France made a machine tool using a milling cutter and gear, with cutting gear accessories; around 1820 , White made the first machine that can process both cylindrical gears and bevel gears. Machine tools with this performance developed again in the second half of the 19th century.
In 1835, Whitworth in the United Kingdom obtained a patent for a worm gear hobbing machine; in 1858, Schiller obtained a patent for a helical gear hobbing machine; after several improvements, until 1897, Pford, Germany, made a hobbing machine with a differential mechanism, which successfully solved the machining skew Gear problem. After making gear-shaped gear shaper, American Ferros made the gear shaper in 1897.
At the beginning of the 20th century, various gear grinding machines came out one after another due to the needs of the automotive industry. Around 1930, the United States made a gear shaving machine; in 1956, it made a gear hobbing machine. Since the 1960s, modern technologies have been applied to some advanced cylindrical gear machining machine tools, such as large-scale machine tools that use digital displays to indicate the depth of tooth cutting; gear hobbing machines and gear shaping machines use electronic servo control systems instead of mechanical transmission chain exchange gears; A programmable controller with a fault diagnosis function is used to control the working cycle to change the cutting parameters; a digitally controlled non-circular gear shaper is adapted to control the gear hobbing machine; an electronic sensor is used to detect the motion error of the drive chain on the gear hobbing machine, and automatic feedback compensation errors .
In 1884, Bill Graham of the United States invented a spur bevel gear gear planer using a single planer according to the development method; in 1900, the United States Bill designed a double-cutter milling straight bevel gear machine.
Due to the needs of the automobile industry, the United States manufactured a straight-bevel gear planer with two planers in 1905, and it was made into a bevel gear milling machine in 1913; in 1923, a quasi-involute bevel gear milling appeared. Gear machine; developed in the 1930s to straighten bevel gears to form a broaching machine, which is mainly used for automobile differential gear manufacturing.
In the 1940s, in order to meet the needs of the aviation industry, the arc bevel gear grinding machine was developed. In 1944, the Swiss Oerlikon company made an extended trochoidal bevel gear milling machine; since the 1950s, it has developed a double cutter body combined end milling cutter to process the extended trochoidal bevel gear milling machine. .
Gear machining machine tools are mainly divided into cylindrical gear machining machine bevel gear machining machine two categories. Cylindrical gear machining machines are mainly used to process various cylindrical gears, racks, and worm gears. Gear hobbing machines, gear shaping machines, gear milling machines, and shaving machines are commonly used.
The hob for the hobbing machine is rough, finely processed, straight, helical, herringbone, worm gear, etc., with a wide machining range, which can achieve high precision or high productivity. And other toothed parts of helical gears, mainly used for machining internal gears of multiple gears; forming milling cutters for gear milling machines are processed according to the indexing method, and are mainly used for machining special toothed instrument gears; gear type razors for shaving machines High-efficiency machine tools for finishing gears; grinding wheels for gear grinding machines, high-precision machine tools for hardened cylindrical gears or gear tool tooth surfaces; honing machines use the sprocket wheels to freely mesh with the gears being processed to eliminate burrs on hardened gears and other tooth surfaces Defective machine tools; gear squeezers use high-hardness non-cutting edge squeeze wheels to freely mesh with the workpiece, grind small unevenness on the tooth surface to improve accuracy and smoothness; gear chamfering machines round the ends of the internal and external meshing sliding gear teeth Machine tools, production gearboxes and other gear shifting mechanisms are indispensable for machining equipment.
Cylindrical gear machining machine tools also include gear hot rolling mills and gear cold rolling mills.
The bevel gear machining machine is mainly used for machining bevel gear teeth such as straight teeth, helical teeth, and extended trochoidal teeth.
Straight bevel gear gear planing machine uses paired planer blades to produce coarse and fine-cut straight bevel gear machine tools in accordance with the development method. There are machine tools that can also plan helical bevel gears, which are most widely used in small batch production.
The double-cutter straight-bevel gear milling machine uses two staggered milling cutters to mill the left and right tooth surfaces of the same tooth groove according to the development method, which has high production efficiency and is suitable for batch production. Due to the relative movement of the milling cutter disc and the workpiece in the toothless length direction, the bottom of the cogged groove is arc-shaped, and the tooth width of the machining module is limited. This machine tool can also be equipped with automatic loading and unloading devices to achieve single machine automation.
A large-diameter broaching cutter head of a straight-bevel gear broaching machine rotates once, and a cogging machine is cut from the solid wheel blank by the forming method. Its bevel gear cutting machine tool has the highest productivity. Due to the complexity of the tools and the high price, each type of workpiece requires a dedicated cutter head, which is only suitable for large-scale mass production. Machine tools are generally equipped with automatic loading and unloading devices.
Spiral bevel gear milling machine uses spiral bevel gear milling cutters to roughen and finish the curved bevel gear hypoid gear machine according to the forming method. There are variants such as precision cutting machine and roughing machine.
Spiral bevel gear grinding machine is used to grind hardened arc bevel gears to improve the accuracy and smoothness of the machine. Its structure is similar to that of arc bevel gear milling machines, but it uses a grinding wheel instead of a milling cutter and is equipped with a dressing wheel. It can also grind hypoid gears.
The extended trochoidal bevel gear milling machine uses an extended trochoidal bevel gear milling cutter, or a double-blade combined face milling cutter, to continuously index the gear cutting machine according to the development method. During tooth cutting, the workpieces of the milling table of the cradle are continuously rotated, and at the same time, the workpiece is reciprocated once by the cradle as the feed motion. The continuous rotation of the milling cutter workpiece allows the workpiece to obtain continuous indexing of a certain number of teeth, and forms a tooth length curve. The additional motion of the rotary table to rotate the workpiece is combined to generate a forming motion, so that the workpiece obtains a tooth profile.
The taper hob for quasi-involute bevel gear milling machine is used to continuously index the gear cutting machine according to the development method. When cutting teeth, the taper hob first cuts with the large end and then cuts with the smaller diameter end. To ensure the same cutting speed throughout the cutting process, the machine tool relies on the stepless speed changer to control the speed of the hob. For continuous rotary motion, machining a workpiece, the shaker reciprocates once. The rotation of the work piece of the cradle generates a generating motion through the differential mechanism, so that the work piece obtains a tooth profile curve with a constant height along the tooth length.
The supporting equipment of the bevel gear machining machine tool is a grinding cutter head, a cutter head, a sharpener, and a pair of bevel gear grinding machines. The bevel gear rolling inspection machine is used to prevent the heat treatment of the teeth from being deformed and quenched. Bed and so on.