Worm gears are the best choice of gearing when high drive reduction is required. Worm wheels resemble helical gears with the addition of a throat cut into the O.D. of wheel. The throat permits the worm wheel to fully envelope the threads of the worm. By adjusting the number of threads on the worm, different ratios can be achieved without altering mounting arrangements. A unique feature of worm and wheel sets is their ability to prohibit back driving.
Worm Gear Manufacturing Options
Pitch: 16 to 64 DP & 1.5 to .5 MOD
Material: Brass for Worm Gear and Stainless Steel for Worm
Thread Style: Single, Double or Quad Start
Bore Size: 1/8” to 1/2”
Number of Teeth: 20 to 56
Pressure Angle: 14.5 to 25
Certain pitches and leads of the worm will not permit the worm wheel to drive the worm. This is useful when an application requires the output to lock-up should the application operate in the opposite direction. The worm is self locking when the helix angle is less than 5Þ. The worm is back drivable when the helix angle is greater than 10Þ. Worm and worm wheel assemblies must be mounted on perpendicular, non-intersecting shafts.
Use the filters below to narrow worm gear options by type, style, pitch, thread style, material, bore size, pressure angle, and number of teeth. WM Berg also designs and manufactures custom worm gears.