The invention provides a method and a device for hot-rolling forming of a cylindrical gear with the big modulus and the large diameter. The method comprises the following steps: S1, a blank is obtained; S2, the blank is arranged on a blank driving shaft and clamped by a clamping device; S3, the blank is heated by an induction heating device; S4, left and right baffle plates are mounted to two ends of a mold; S5, a driving device drives the mold and the blank to rotate in opposite directions at a certain speed ratio, and meanwhile, the mold is fed radially through a linear driving device; S6, when the center distance between the mold and the blank reaches a predetermined value, radial feeding of the mold is stopped, the mold is rotated continuously for two circles, and then the mold and the blank are rotated reversely for two circles simultaneously and stopped; S7, the clamping device loosens, and the blank is discharged. The device comprises a rack, the blank driving shaft, a mold driving shaft and an electromagnetic induction coil. According to the method and the device, the cylindrical gear is integrally formed by one step through continuous local plastic deformation, the production efficiency is improved, the materials are saved, and the product performance can be enhanced.

Method and device for hot-rolling forming of cylindrical gear with big modulus and large diameter

The invention relates to a gear rolling forming method adopting taper rolling wheels. The at least one taper rolling wheel is used for rolling a blank, the tooth shapes of the taper rolling wheels are changed in the axial direction, all rolling wheels rotate in the same direction, the blank is fed in the axial direction, and tooth graduation in the initial rolling stage, lug defect restraining in the forming stage and tooth shape profile finishing in the rolling later period are sequentially achieved; and during rotation of the taper rolling wheels, along with axial feeding of the blank, the uniform tooth graduation, tooth shape lug-free forming and tooth profile finishing processes are sequentially carried out and completed at the outer edge of the blank, and accurate forming in the gear rolling process is achieved. According to the gear rolling forming method, the technological process is simple and convenient, implementation is easy, the forming quality is good, machining for cutting off lugs and grinding for guaranteeing the tooth profile size accuracy are eliminated, materials and machining hours are saved, the production efficiency and the forming quality of gear rolling forming are obviously improved, and the production cost is reduced.

Gear rolling forming method adopting taper rolling wheels

The invention disclose a multi-pass simultaneous rolling die of large-diameter toothed workpieces and a rolling method. The rolling die includes N rolling die bodies; the center distance between the rolling die bodies and the workpiece blank is the same; and the rolling die bodies are evenly arranged at equal intervals along the circumference of the workpiece blank and are staggered at a set distance in turn. The rolling method includes the steps that the workpiece blank is clamped first; the rolling die bodies are axially fed to the designated positions; the end surfaces, close to the lead-insection of the workpiece blank, of the rolling die bodies are all aligned; the rolling die bodies are simultaneously aligned with the end surfaces of the lead-in section of the workpiece blank; the rolling die bodies are pressed into the workpiece blank by axial advancement; the workpiece blank actively rotates; the rolling die bodies rotate by friction and toothed engagement; the rolling die bodies are fed axially at the same speed to complete toothed roll forming on the workpiece blank; and when the axial feeding of the Nth rolling die body is completed, the rolling die is no longer in contact with the workpiece blank. According to the rolling die and the rolling method, the processing of the large-diameter toothed workpieces is achieved, and the rolling die has the advantages of high production efficiency, small rolling force and complete toothed shapes.

Multi-pass simultaneous rolling die of large-diameter toothed workpieces and rolling method

The invention discloses an involute-gear rolling mold and forming technology. The rolling mold comprises a first rolling mold body and a second rolling mold body which are parallelly arranged at intervals, and the tooth number and the mold number of the two molds are same; a zero-pass tooth area, a first-pass tooth area, a second-pass tooth area and the like, a N-pass tooth area are sequentially arranged on the first rolling mold body; the tooth type in all the pass tooth areas is same; the first rolling mold body and the second rolling mold body are same in structure, and tooth types are formed in an involute mode; the areas from the zero-pass tooth area to the N-pass tooth area are clockwise arranged on the first rolling mold body, and are clockwise arranged on the second rolling mold body. According to the involute-gear rolling mold and forming technology, blanks are rolled in a fixed-point mode, the center distances between the rolling mold bodies are fixed, the rolling mold does not need to be fed in a radial-direction mode in the forming process, blanks are balanced in stress, accurate in positioning and small in uneven deformation; the speed forced synchronization rolling mode is adopted, dynamic graduation of the tooth type in the forming process is achieved, and the tooth-distance accumulative errors caused by free-graduated rolling are eliminated.

Involute-gear rolling mold and forming technology

The invention discloses a gear rolling forming method for overcoming a tooth-form lug defect. At least one rolling wheel is used for rolling a blank, the modulus and pressure angle of the rolling wheels are the same as those of a forming gear, all the rolling wheels rotate in the same direction and perform radial feed along the blank, while the rolling wheels roll the blank, a cylindrical wheel is used for rolling a gradually-formed tooth-form tooth crest of the blank and gradually withdraws in the radial direction so as to make lugs round through rolling along with radial stretching of the tooth-form tooth crest, the lugs are formed in rolling of the tooth-form tooth crest, and therefore the forming gear of which the tooth crest is relatively flat and free of the lugs or is with small lugs is obtained. According to the method, in the original rolling process, the cylindrical wheel is additionally arranged and used for synchronously flattening the lugs appearing on the tooth-form tooth crest through rolling, the process is simple and convenient and easy to implement, quality is good after forming, extra machining for cutting off the lugs is omitted or substantially reduced, material is saved, the production efficiency of forming the cylindrical gear through rolling is obviously improved, and the production cost is lowered.

Li Jin

Papers

Gear rolling forming method for overcoming tooth-form lug defect