Yamaha 3-axis model, 4-axis model owner manual 11-39

Chapter 11 FXYBX/SXYBX

Replacement period

The harmonic drive replacement period is determined by the total number of wave generator rotations. A calculation example is shown below.

The recommended harmonic drive replacement period is 8.4⋅108 rotations (at usage atmospheric temperature range 0°C to +40°C).

The harmonic drive should be replaced earlier if the robot operation duty is high or if the temperature conditions are poor.

[Replacement period] =8.4⋅108/(n⋅60⋅h⋅D⋅N⋅θ) years

n: Number of robot movements in one minute

θ : Average axis rotation in one movement

N : Deceleration rate (50 for ZRS R-axis)

h : Number of operation hours per day

D : Number of operation days per year

(Example) The YK500X X-axis harmonic drive replacement period when the axis rotates an average quarter turn every movement and the robot moves ten times in one minute. (Operation hours: 24 hours/day, number of operation days: 240 days/year)

n	: 10
θ	: 0.25
N	: 50
h	: 24
D	: 240
[Replacement period]	=8.4⋅108/(n⋅60⋅h⋅D⋅N⋅θ)
	=8.4⋅108/(10⋅60⋅24⋅240⋅50⋅0.25)

=19.4 years

Consult with YAMAHA when actually replacing the harmonic drive.

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