Spiral Bevel Gears are to straight bevel gears what a helical gear is to a spur gear.

Spiral Bevel Gears supersede straight bevel gears where greater strength, higher speed and/or less noise is needed in an angle gear set.

In order to get better performance out of a parallel shaft application a helix angle is introduced in the straight tooth.  This helical tooth shape gets more teeth engaged, which results in a gear set that can operate under greater loads at higher speeds without excessive noise.

In the same way a spiral angle can be introduced in a bevel tooth form, which allows more tooth engagement and load sharing.

Spiral Bevel Gears are recommended when speeds exceed 1000 RFM or 1000 SFPM.

With the right tooth form and equipment Spiral Bevel Gear teeth can also be ground for greater accuracy resulting in even less noise and vibration.

Nissei is capable of supplying low cost ground-tooth Zerol®, spiral and hypoid pinions and gears. This is made possible by Nissei's super abrasive grinding technology using "CBN" plated grinding wheels.

Nissei's Spiral Bevel Gears are available up to:
M-8.0, 3.0 D.P., 12" P.C.D.

Straight Bevel Gears are the oldest, the simplest and most widely used of all bevel gears.

Originally, straight bevel gears were produced with full length and depth contact.  This means that the straight bevel gear and pinion contacted with each other over the full tooth surface even at light load.

This line contact pattern doesn't allow much room for error in assembly before noise, vibration and premature failure are introduced. 

Nissei manufactures straight bevel gears using Gleason Coniflex® machines.  The Coniflex® method introduces lengthwise and profile crowning.  Crowning of the gear tooth allows localization of the contact pattern (relieves sensitivity to concentrated edge loading).  This makes the gears easier to assemble and gives the straight bevel gear better performance.

Nissei's Coniflex® Straight Bevel Gears can be used in applications with speeds up to 1000 FPM or 1000 RPM.

Nissei's Straight Bevel Gears are available up to:
M-8.0, 3.0 D.P., 12" P.C.D.

Zerol® Bevel Gears are "sort of" a cross between straight bevel gears and spiral bevel gears.

The Gleason Works developed the Zerol® tooth form as a replacement for straight bevel gears that could be produced on spiral bevel gear machinery.  There is greater control of the tooth contact pattern with Zerol® bevel gears than with straight bevel gears.

Zerol® bevel gears offer the same minimal axial thrust as straight bevel gears allowing the most compact and low cost bearings.

An added benefit of the Zerol tooth over the straight bevel tooth is that it can be ground.

Nissei is capable of supplying low cost ground-tooth zerol, spiral and hypoid pinions and gears. This is made possible by Nissei's super abrasive grinding technology using "CBN" plated grinding wheels.

Nissei's Zerol Bevel Gears are available up to:
M-8.0, 3.0 D.P., 12" P.C.D.

Hypoid Bevel Gears can be thought of as a "kind of " spiral bevel gear.

Spiral bevel gear and pinion axes intersect where they cross each other in the same plane.  Hypoid axes, on the other hand, do not intersect each other where they cross.  The hypoid pinion centerline is not in the same plane as the hypoid gear centerline. they are offset from each other.

This offset introduces 2 potential advantages:

1. Ergonomically it is better suited to some applications such as the rear axle on an automobile.  The pinion offset lowers the drive shaft being less intrusive to the passenger space.
2. The pinion offset also requires the pinion to be larger, which results in a stronger pinion and allows for more gear teeth to be in engagement and improved motion transmission and load sharing.

Nissei is also capable of supplying low cost ground-tooth Zerol®, spiral and hypoid pinions and gears. This is made possible by Nissei's super abrasive grinding technology using "CBN" plated grinding wheels..

Nissei's Hypoid Bevel Gears are available up to:
M-8.0, 3.0 D.P., 12" P.C.D.

High Ratio Hypoid Gears are a modified hypoid gear.

The H.R.H. is a modified Hypoid with a maximum ratio of about 1:360. It can replace the worm in many applications but is much more compact and efficient.

Nissei has developed a whole line of gear motor products around this gear design and currently supplies this gearset for applications such as: Automotive Power Steering Assist, Index Table Drives, etc...

Nissei is capable of supplying low cost ground-tooth Zerol®, spiral and hypoid pinions and gears. This is made possible by Nissei's super abrasive grinding technology using "CBN" plated grinding wheels.

Nissei's High Ratio Hypoid Gears are available up to:
M-3.0, D.P.-8.0, P.C.D.-10"

Spur Gears are the most common type of gear in use.

The spur gear is manufactured on a cylindrical blank and is used in applications where input and output are in parallel planes.  The teeth generally have full-face contact though length-wise crowning is possible.

Spur gears are used to drive externally where the pinion and gear mating surfaces are located on the outside diameter or they drive internally where the outside diameter of one member drives the inside diameter of the other member such as in a planetary system.

Spur gears tend to be noisy at higher speeds.

Nissei's Spur Gears are available up to:
M-8.0, 3.0 D.P,. 14" P.C.D.

Helical Gears are similar to spur gears but the teeth lie at an angle to the axis.

The helix angle on a helical gear was introduced to achieve higher performance out of parallel axis gear sets.

The helical tooth form brings more teeth into mesh than a spur gear is capable of.  This load sharing increases the overall power capability of the gear set and also allows for quiter, smoother operation at high speeds.

Nissei's Helical Gears are available up to:
M-8.0, 3.0 D.P,. 14" P.C.D.

Worm Gears are used when large gear reductions are needed.

It is common to see worm gear ratios of 20:1 and even as high as 300:1.

Before deciding that a worm gear is your best option take a look at Nissei's High Ratio Hyoid.  The High Ratio Hyoid offers the high reduction of a worm set in a smaller, more efficient package.

Nissei's Worm Gears are available up to M-2.0 in a variety of sizes and materials.