What is the reference diameter of a gear?
Center Distance and Backlash
| Terms | Symbols | Gear |
|---|---|---|
| Reference diameter | d | 75 |
| Addendum | ha | 2.5 |
| Dedendum | hf | 3.125 |
| Tooth Depth | h | 5.625 |
How is worm gear diameter calculated?
NOTE: Tooth data (Addendum, Full Depth, Etc.) is same as for Spur Gears….Worm Gear Formula Table.
| To Find | Rule | Formula |
|---|---|---|
| Worm Gear Throat Diameter | Add 2 Addenda to Pitch Diameter | Throat Diameter = (2 x Addendum) + Pitch Diameter |
| Worm Gear Outside Diameter | Add 3 Addenda to Pitch Diameter | Outside Diameter = (3 x Addendum) + Pitch Diameter |
What is the worm gear pitch diameter?
1. Pitch Diameter –The diameter of the pitch circle is the “imaginary” circle on which the worm and worm gear mesh. 2. Working Depth – The maximum distance the worm thread extends into the tooth space of the gear.
What is base diameter of gear?
BASE DIAMETER (Db) is the diameter of the base cylinder from which the involute portion of a tooth profile is generated. CIRCULAR THICKNESS (t) is the length of arc between the two sides of a gear tooth on the pitch circle, unless otherwise specified.
How do you determine gear size?
The gear ratio is calculated by dividing the output speed by the input speed (i= Ws/ We) or by dividing the number of teeth of the driving gear by the number of teeth of the driven gear (i= Ze/ Zs).
How do you find the base circle diameter of a gear?
Root Diameter (df) is the diameter of the root circle; its value is: df = m (z – 2.5) or df = de – 2h. Center Distance (dc) is the distance between the shafts of the gear and the pinion; its value is: dc = (D + d) / 2, where “D” corresponds to the pitch diameter of the gear and “d” to the pitch diameter of the pinion.
What is worm gear pitch?
The pitch in worm gears is the axial pitch, the pitch always being expressed in the axial plane. When the helix angle exceeds 15º normal pitch may be calculated by multiplying the axial pitch by the cosine of the helix angle. This pitch is measured perpendicular to the sides of the thread.
How do you find the diameter of a gear?
Which is the smallest diameter of worm gear?
Root Diameter – The smallest diameter of the worm gear. It is equal to the diameter of the root circle. 1. Addendum – The distance from the pitch circle to the throat circle. 2. Dedendum – The distance from the pitch circle to the base of the tooth. It is equal to the addendum plus the working clearance.
What do you need to know about worm gears?
Worm Gear. A worm is a gear with one or more cylindrical, screw-like threads and a face width that is usually greater than its diameter. A worm has a center hole (bore) for mounting the worm on a shaft. Worm gears, like worms, also are cylindrical and bored for mounting on a shaft.
What do you call a single envelope worm gearset?
If the worm gears are machined basically as crossed helical gears the result is a highly stress point contact gear. However normally the wormwheel is cut with a concave as opposed to a straight width. This is called a single envelope worm gearset.
How to calculate maximum efficiency of worm gear?
The curve peak is in the middle of the interval [0; 90- r] and the theoretical maximum efficiency of a worm gearing is then calculated as follows: h max = tan (45 -r /2) / tan (45 +r /2) The vertical axis shows gearing efficiency, the horizontal axis shows the pitch angle, and individual curves are for different friction coefficients.