The procedure is similar to form-milling of spur gear. In this case a universal milling machine is used. The module of cutter chosen is equal to the normal module of helical gear to be cut. With the cutter mounted on the arbor of horizontal milling machine, the table is set to the helix angle of the gear. To carry out the helical milling, the dividing head is connected to the lead screw of the table. The gears are chosen so as to give the necessary lead on the gear. Lead of helical gear is given by:
L = d. cot
where L = Lead of the gear,
d = reference diameter of the gear, and
= helix angle of the gear.
The gear is then cut similar to cutting a spur gear. If the helix angle of the gear is large, it may not be possible to set the table of the universal milling machine to the required helix angle. In this case a vertical milling attachment is used and is set in the horizontal position, setting the cutter at 90o from the normal position. The table is then set to the lead angle of the helical gear.
L = d. cot
where L = Lead of the gear,
d = reference diameter of the gear, and
= helix angle of the gear.
The gear is then cut similar to cutting a spur gear. If the helix angle of the gear is large, it may not be possible to set the table of the universal milling machine to the required helix angle. In this case a vertical milling attachment is used and is set in the horizontal position, setting the cutter at 90o from the normal position. The table is then set to the lead angle of the helical gear.
3 comments:
Thanks for sharing with us
Malkar Industries Spur Gears, Worm Gears, Lead Screws,Serration Cutters, Helical Gears.
Can you please define the process of Gear Train design to transmit lead to the helical gear while cutting on the milling machine.
Can I ask, about the formula or computation of making a helical gear. Formula about the gear atach in the indexing head for driving gear to driven gaer.
Post a Comment