ROBO Cylinder GR3LM, Instruction Manual

Page: 37 / 128

1. Specifications Check
31
1.3 Operating Conditions
It is necessary to satisfy the conditions stated below to use the product. Conduct the following calculation
to make sure it is satisfied.
1.3.1 Grippping Force
[1] Slide Types
Procedure 1 : Check for the necessary grip force and
transportable work piece mass
Procedure 2 : Check for the vertical allowable load of the fingers
and allowable moment
Procedure 1 : Check for the necessary grip force and transportable work
piece mass
If a work piece is to be gripped on the fingers with the
friction force created by the grip force, the formula to
calculate the necessary grip force is as follows;
(1) In case of ordinary transportation
F : Grip Force [N]……Sum of pressing force on each finger
μ : Coefficient of static friction between finger attachment and
work piece
m : Mass of work piece [kg]
g : Gravitational acceleration [= 9.8m/s
2
]
The condition to grip the work piece statically and that the work
piece would not drop is;
F μ > W
F >
The necessary grip force assuming the safety factor recommended
for ordinary transportation is 2 should be;
F > × 2 (safety factor)
When coefficient of friction is μ 0.1 to 0.2;
F > × 2 = (10 to 20) × mg
* The mass of a transportable work piece will get higher as the coefficient of static friction is higher.
However it is necessary to that enables it to obtain a grip force of 10 to 20 times or more to ensure
the safety.
mg
μ
mg
μ
mg
0.1 to 0.2
For ordinary work piece transportation;
Necessary grip force ⇒ 10 to 20 times or more of work piece mass
Transportable work piece mass ⇒ 1/10 to 1/20 or less of grip force
Friction
coefficient
μ
F / 2
W (m g)
F / 2
coefficient
μ
F / 3 F / 3
F / 3
W (m g)
Friction
↓