Boston helical gears are stocked both right and left hand, made with a 45° helix angle. They are designed to transmit motion and power between nonintersecting shafts which are positioned either parallel (opposing hand) or at 90° to each other (same hand). Because these gears are top-hobbed, there is extremely close concentricity between the pitch diameter and the outside diameter.
Helical gears offer additional benefits relative to Spur Gears, those being:
– Improved tooth strength due to the elongated helical wrap-around.
– Increased contact ratio due to the axial tooth overlap.
– Helical Gears tend to have greater load carrying capacity than Spur Gears of similar size.
– Because of the above, smoother operating characteristics are apparent.
All Boston Helicals are cut to the Transverse Diametral Pitch System, resulting in a higher Normal Diametral Pitch Number.