Brief
The Cycloidal gear is a type of gear that use tooth profile based on cycloidal curve to generate high reduction ratio up to 1:300
A cycloidal curve is a curve of one circle roles around the outside or inside of another circle.
When the circle roles a long another circle outside, it makes a curve called Epicycloid Curve.
more details 👇👇 https://en.wikipedia.org/wiki/Epicycloid
When the circle roles over another circle from outside, it makes a curve called Hypocycloid Curve.
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The Cycloid gear profile takes advantages of both of these curves to ensure constant angular velocity, and construction provides the advantages over a typical shape of gear "Spur Gear".
The Main Parts of Cycloidal Gear Box
1. Input Shaft: it is eccentric shaft connected directly with the cycloid disk.
2. Cycloid Disk: a disk with cycloid curve profile that transfer the mechanical power from input shaft to external load.
3. Output Disk: a disk with pins connected to the cycloid disk
Cycloidal Disk - Design
1. Cycloidal Curve
The cycloidal curve defined by the two equations, it is better to use CAD software to enter the two equations and it will be done.
Equation Parameters R : Radius of Rotor that holds the fixed rollers.
Rr : Radius of fixed ring pin.
E : Eccentricity "Offset".
N : Number of rollers.
t : angle step in radians.
t = (theta/360)*(2*pi) ---> theta: between [ 0 - 360] degrees.
2. Cycloidal Disk Holes
The number of holes is equal to the number of Pins in the output Disk
H1 = Diameter of Output Pin + 2 E
Output Disk - Design
The Diameter "D1" must be equal to the diameter "D1" in the Cycloidal disk, and consider the diameter of output pin as a function of the holes diameter in the Cycloidal disk as per the pervious equation.
The number of Output Pins supposed to equal the number of holes in Cycloidal disk.
Input Shaft - Design
The Input shaft is eccentric shaft with a certain offset value "E", connected directly with Cycloidal disk.
Reduction Ratio
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