Brochure

Note 3)
Symbol Specifications
Absorbed energy
Kinetic energy
Thrust energy
Thrust
Gravitational acceleration (9.8)
Dropping height
Moment of inertia around the center of gravity
Operating frequency
Distance between rotational center and impact point
Shock absorber’s stroke
Torque
Ambient temperature
Collision speed
Impact mass
Equivalent mass
Angular speed
Friction coefficient
Unit
J
J
J
N
m/s
2
m
kg·m
2
cycle/min
m
m
N·m
°C
m/s
kg
kg
rad/s
—
<Symbol>
Note 4) For the formula for moment of inertia Ι (kg·m
2
), refer to the rotary
actuator’s catalog.
E
E
1
E2
F
g
h
Ι
n
R
S
T
t
υ
m
Me
ω
μ
Note 4)
In order for the shock absorbers to operate accurately for long hours,
it is necessary to select a model that is well-suited to your operating
conditions. If the impact energy is smaller than 5% of the maximum
absorbed energy, select a model that is one class smaller. Use the
RJ20 and 27 under the conditions mentioned below.
RJ20: Cylinder bore size ø32 or higher or thrust 240 N or higher
RJ27: Cylinder bore size ø40 or higher or thrust 380 N or higher
Caution on Selection
Model Selection Series RJ
Load
Load
Load
Load
Type of Impact
1
Type of
impact
Collision speed
υ
Kinetic energy
E1
Thrust energy
E2
Absorbed energy
E
Equivalent mass
Me
Impact of thrust of
load (Downward)
(Impact of thrust
from sources
other than air
cylinder actuation)
Impact of thrust of
load (Upward)
(Impact of thrust
from sources
other than air
cylinder actuation)
Load on
conveyor
(Horizontal)
Swing impact
(With torque)
Note 1)
Note 2)
υ
— · m
·
υ
2
1
2
F
· S + m · g · S
E
1 + E2
— · E
2
υ
2
1
2
υ
— · m
·
υ
2
F · S – m · g · S
E
1 + E2
— · E
2
υ
2
— · m
·
υ
2
1
2
υ
m · g · μ · S
E
1 + E2
— · E
2
υ
2
ω
· R
E
1 + E2
— ·
Ι
· ω
2
1
2
T
· —
S
R
— · E
2
υ
2
Note 1) This is the momentary speed at which an object is impacting against a shock absorber. The collision speed is υ = 2υ when the speed (average
speed υ) is calculated from the air cylinder’s stroke time.
Note 2) This is the theoretical mass, which is converted into the mass of the impacting material under no thrust collision conditions. Hence, E = —·Me·υ
2
Note 3) R: The distance between rotational center and impact point. Set R at the minimum installation radius (Caution 3. Rotating angle on page 11) or higher.
1
2
4