Easy Automation Improvement Example V.6-2
Machine Door Opening/Closing Mechanism
This system creates tapped holes in aluminum die-cast boxes and finishes (mills) the holes. A vertical articulated robot is used to put in / take out parts to/from the processing machine. Air cylinders are used to open/close the door to the processing machine.
Current problems using Air Cylinders
A decision was made to improve the current system to meet the plan for 3% production increase. The current cycle time is 92.7 seconds, and the annual production output is 250,200 pieces.
A 3% increase of production output means increasing the production output to 257,706 pieces or more, which requires the cycle time to be reduced to 90.1 seconds or less.
After studying the operating condition, the goal was set to shorten the door opening/closing time. With the current system, it takes 4.6 seconds to open/close the door (2.3 seconds x twice).
When the air volume was adjusted with the speed controller to raise the air cylinder speed, the stopping shock caused the door to bounce.
This makes it impossible to raise the air cylinder speed, which means that the cycle time cannot be shortened, either.
Automation Improvements Achieved by the ROBO Cylinder®
1. Shorter cycle time by acceleration & deceleration setting function
The air cylinders that were used to open/close the door to the processing machine were replaced with ROBO Cylinders®.
The ROBO Cylinder® lets you set its speed, acceleration and deceleration separately.
By setting the deceleration gradual and the speed and acceleration high, the stopping shock was eliminated and the cycle time became shorter.
The door opening/closing time decreased by 3.0 seconds to 1.6 seconds (0.8 second x twice), and the cycle time dropped to 89.7 seconds. As a result, approx. 3.4% of production increase was made possible with the system operating hours remaining the same.
|Annual production output|
(Approx. 3.4% of production increase)
2. If the system is to be used for 10 years, four replacement air cylinders will be required; on the other hand, you won't be needing any replacement ROBO Cylinder®
The air cylinder drops its speed (thrust force) after 2 million operations or so due to deterioration of gaskets, etc.
With this system, the air cylinders used for the input side door and removal side door had to be replaced once every four years.
ROBO Cylinders® can ensure stable operation after many hours of use.
Under the use conditions in this application, the service life of the ROBO Cylinder® is calculated as 10 million operations or more, or 10 years or longer.
|Number of replacement units required|
3. Replacing with the ROBO Cylinders® was easy
The solenoid valve mode makes replacing air cylinders with ROBO Cylinders® easy.
Solenoid valve mode:
One method for controlling ROBO Cylinders®
A start signal is provided for each position number, so all you need is to turn ON the applicable input signal, and the robot will operate according to the data corresponding to the target position number.
This method is called the "solenoid valve mode," because a ROBO Cylinder® can be operated in the same way as an air cylinder being directly driven with a solenoid valve.
Cost Cutting Effect
|Processing charge (*2)||$0.66*/minute|
|Operating hours a day||21.5 hours/day|
|Annual operation days||300 days|
*2 Processing charge:
Unit processing cost per minute. In general, the processing charge is calculated according to the conditions below:
 Initial cost and residual value after depreciation of the owned line
 Cost of running the line
 Labor cost and administrative cost associated with the operators
(2) Comparison of air cylinder and ROBO Cylinder®
|Item||System using air cylinder||System using ROBO Cylinder®|
|Modification cost||-||Total amount = $6,700*|
|Operating hours (day)||21.5 hours/day||21.5 hours/day|
|Cycle time||92.7 seconds||89.7 seconds|
|Production output (year)||250,200 pieces/year||258,600 pieces/year|
|Purchase cost of
(Assuming 10 years)
|Air cylinder $400*/unit
x 2 units/system
x 2 replacements
(replaced periodically once every 4 years)
(3) Annual Cost Cutting Effect
|ROBO Cylinder®||Air Cylinder|
|Production Output||258,600 pieces/year -||250,200 pieces/year =||8,400 pieces/year|
|Difference =||8,400 pieces/year|
|Cost of processing 8,400 pieces
with the original system
|8,400 pieces x 1.545 min.
(original cycle time: 92.7 sec.)
|x $0.66* / minutes =
|Air Cylinder||ROBO Cylinder®|
|Cost of purchasing
(air cylinder $1,600* / 10 years)
By adopting the ROBO Cylinders®, the production output increased by 3.4 % with the daily operating hours remaining the same, and $8,560* of processing cost was saved a year.
What's more, the ROBO Cylinder® need not be replaced for at least 10 years.
The result is $160* in extra savings per year.
* Exchange Rate: 1(USD) = 100(Japanese Yen)
IAI Sales & Tech Support Lines
Please call IAI America from 8:30 am to 5:00 pm at these locations:
Eastern U.S. office: (888) 354-9470
Central U.S. office: (800) 944-0333
Western U.S. office: (800) 736-1712
Outside office hours, please use our contact form.