Harmonic Drive FHA Series User Manual

Harmonic Drive LLC 800-921-3332
22
Chapter 2 Guidelines for sizing
2
2
Inertia
(kg•m ) (kgf•cm•s )
1000 10000
100 1000
10 100
1 10
0.1 1
0 20 40 60 80
Max. speed (r/min)
FHA-40C-160
FHA-40C-100
FHA-32C-160
FHA-32C-100
FHA-25C-160
FHA-40C-50
FHA-25C-100
FHA-32C-50
FHA-17C-160 FHA-25C-50
FHA-17C-100
FHA-17C-50
• Equivalent dynamic radial load
The equivalent dynamic radial load is:
2 (Frav (Lr + R) + Faav
.
La)
P
C
= X
.
(
Frav +
)
+ Y
.
Faav (6)
dp
Where, the variables of the formula are:
Frav: Average radial load in N(kgf); obtained by formula (2).
Faav: Average axial load in N(kgf); obtained by formula (3).
dp: Circular pitch of roller: See Fig.1 and Table 1.
X: Radial load factor; obtained by formula (5)
Y: Axial load factor; obtained by formula (5')
Lr, La: Loading point in mm; See Fig.1.
R: Offset; See Fig.1 and Table 1.
• Life of cross roller bearing
Calculate the life of cross roller bearing with the formula below:
10
6
C
10/3
L
B-10
= x (7)
60 x Nav
(
fw
.
Pc
)
Where, the variables of the formula are:
L
B-10: Life of cross roller bearing in hour
Nav: Average output speed in r/min; obtained by formula (4).
C: Basic dynamic load rating in N (kgf). See Table 1.
Pc: Average dynamic radial load in N (kgf); obtained by formula (6) below.
fw: Load factor:
For smooth operation without shock or vibration: fw=1 to 1.2
For normal operation: fw=1.2 to 1.5
For operation with shock and/or vibration: fw=1.5 to 3
• Life of cross roller bearing for swaying motion
Calculate the life of cross roller bearing with the formula below:
10
6
90 C
10/3
L
OC
= x x (8)
60 x n
1 ?
(
fw
.
Pc
)
Where, the variables of the formula are:
Loc: Life of cross roller bearing in hour
n
1
: Average output speed in r/min; obtained by formula (4).
C: Basic dynamic load rating in N (kgf). See Table 1.
Pc: Equivalent dynamic radial load in N (kgf); obtained by formula (6).
fw: Load factor:
For smooth operation without shock or vibration: fw=1 to 1.2
For normal operation: fw=1.2 to 1.5
For operation with shock and/or vibration: fw=1.5 to 3
θ : Half of sway angle; See the right figure.
Sway Motion
When the sway angle is less than 5 degrees, consult to Harmonic
®
drive systems,
because fretting wear may occur for the operation caused by no oil film
between the race and the rolling element.

Harmonic Drive FHA Series Specifications

General

Brand	Harmonic Drive
Model	FHA Series
Category	Controller
Language	English