YOU WILL WANT TO to Use Worm Gears
There is one especially glaring reason why one would not select a worm gear more than a typical gear: lubrication. The movement between your worm and the wheel gear faces is entirely sliding. There is absolutely no rolling component to the tooth get in touch with or interaction. This makes them fairly difficult to lubricate.
The lubricants required are usually high viscosity (ISO 320 and better) and therefore are tough to filter, and the lubricants required are usually specialized in what they do, requiring something to be on-site specifically for that type of equipment.
Worm Gear Lubrication
The main problem with a worm gear is how it transfers power. It is a boon and a curse simultaneously. The spiral movement allows huge amounts of reduction in a comparatively small amount of space for what’s required if a typical helical gear were used.
This spiral motion also causes an incredibly problematic condition to be the principal mode of power transfer. This is often called sliding friction or sliding put on.
With a typical gear set the energy is transferred at the peak load point on the tooth (known as the apex or pitchline), at least in a rolling wear condition. Sliding takes place on either side of the apex, however the velocity is fairly low.
With a worm gear, sliding motion may be the only transfer of power. As the worm slides across the tooth of the wheel, it gradually rubs off the lubricant film, until there is absolutely no lubricant film still left, and for that reason, the worm rubs at the metal of the wheel in a boundary lubrication regime. When the worm surface area leaves the wheel surface, it accumulates more lubricant, and worm drive shaft begins the process over again on another revolution.
The rolling friction on an average gear tooth requires little in the form of lubricant film to complete the spaces and separate the two components. Because sliding happens on either aspect of the gear tooth apex, a somewhat higher viscosity of lubricant than is definitely strictly needed for rolling wear must overcome that load. The sliding happens at a relatively low velocity.
The worm on a worm set gear turns, even though turning, it crushes against the load that’s imposed on the wheel. The only method to prevent the worm from touching the wheel is certainly to have a film thickness huge enough to not have the entire tooth surface area wiped off before that part of the worm has gone out of the load zone.
This scenario requires a special sort of lubricant. Not just will it will have to be a comparatively high viscosity lubricant (and the higher the strain or temperature, the bigger the viscosity should be), it must have some way to help overcome the sliding condition present.
Read The Right Way to Lubricate Worm Gears to find out more on this topic.
Custom Worm Gears
Worm Gears are correct angle drives providing huge speed ratios on comparatively short center distances from 1/4” to 11”. When properly mounted and lubricated they function as the quietist and smoothest working type of gearing. Due to the high ratios possible with worm gearing, optimum speed reduction could be accomplished in much less space than many other types of gearing. Worm and worm gears operate on non-intersecting shafts at 90° angles.
EFFICIENCY of worm gear drives depends to a huge level on the helix position of the worm. Multiple thread worms and gears with higher helix position prove 25% to 50% more efficient than single thread worms. The mesh or engagement of worms with worm gears generates a sliding action causing considerable friction and greater lack of efficiency beyond other types of gearing. The use of hardened and floor worm swith bronze worm gears improves efficiency.
LUBRICATION can be an essential factor to improve effectiveness in worm gearing. Worm equipment action generates considerable warmth, decreasing efficiency. The quantity of power transmitted at a given temperature improves as the efficiency of the gearing boosts. Proper lubrication enhances efficiency by reducing friction and warmth.
RATIOS of worm gear sets are dependant on dividing the number of teeth in the apparatus by the number of threads. Thus solitary threads yield higher ratios than multiple threads. All Ever-Power. worm gear models can be found with either still left or right hand threads. Ever-Power. worm gear sets can be found with Single, Dual, Triple and Qua-druple Threads.
Basic safety PROVISION: Worm gearing should not be used as a locking mechanism to carry large weights where reversing action could cause harm or damage. In applications where potential harm is nonexistent and self-locking is desired against backward rotation then use of a single thread worm with a low helix angle instantly locks the worm gear drive against backward rotation.
MATERIAL recommended for worms is definitely hardened steel and bronze for worm gears. Nevertheless, depending on the application unhardened steel worms operate adequately and more economically with cast iron worm gears at 50% horsepower ratings. Furthermore to steel and hardenedsteel, worms are available in stainless, aluminum, bronze and nylon; worm gears can be found in steel, hardened steel, stainless, light weight aluminum, nylon and nonmetallic (phenolic).
Ever-Power also sells gear tooth measuring devices called Ever-Power! Gear Gages decrease mistakes, save time and money when identifying and ordering gears. These pitch templates can be found in nine sets to recognize all the standard pitch sizes: Diametral Pitch “DP”, Circular Pitch “CP”, External Involute Splines, Metric Module “MOD”, Stub Tooth, Fine Pitches, Coarse Pitches and Unusual Pitches. Make reference to the section on Equipment GAGES for catalog numbers when ordering.