Precision positioning switches
- Detection of 0.1 mm-scale slight movements
- Improvements in mechanical precision
- Savings in space and cost required
Latest use cases
Control of the X- and Y- axes with a precision of 1 μm
Positioning of the end face of equipment
Control of the starting point of equipment
Seating confirmation of workpiece
Use as a stopper for 300 kg static loads
Correction of the position of worn edged tools with a precision of 0.5 μm
Zero seek for robots
Correction of the thermal displacement of the Z-axis with a precision of 0.5 μm
Positioning within machine tools
Use in adverse environments caused by scattering chips and cutting-oil
This is what distinguishes precision positioning switches from other manufacturers' sensors!
Metrol precision positioning switches are precision mechanical devices.
Like a Swiss mechanical watch, it is assembled from over 7,000 original precision components based on skilled craftsmanship. Over 700 kinds of products are manufactured on the production line, which, though automated, is under the control of responsible individuals.
Metrol conducts integrated quality control throughout the production, quality inspection and delivery processes within its Tokyo factory and ships the products thus manufactured to customers all over the world.
Comparison with other manufacturers' sensors
|Contact type||Non-contact type|
Optical fiber sensor
|Precision||0.5 μm minimum||N/A
(approx. 50 to 100 μm)
|1 μm minimum||10 μm minimum|
(precision mechanical type)
(snap action mechanism)
(because of no amplifier)
(because of amplifier)
|Influence of the
|Influenced by temperature,
electric fields and magnetic fields
(influenced by the material
and color of the object)
|Influence to the
|None||Influenced by the
(water, oil, etc.)
|Usability in special
high temperatures or
in a vacuum or
|Life||3 million to
|100,000 to 500,000
Disadvantages of precision positioning switches
- Precision positioning switches are unable to detect things that cannot be touched including liquid and soft objects.
- Tact time is prone to be long because workpieces require contact.
- Vibration, impact and the operating speed (10 mm/minute maximum) at the mounting location may cause a chattering phenomenon in which electric signals keep turning on and off intermittently.
(Chattering can be prevented by taking the initial signal or by selecting NO type switches.)
Product specifications (typical model listed)
|Typical model||Ultra-small type PT series|
|Repeatability||0.001 mm for both ON and OFF (range)|
|Contact precision life||3 million operations|
|Operating modes||A:NO (Normally open)||B:NC (Normally closed)|
|Movement before the start of operation||Approx. 0.3 mm||Nearly zero|
|Protective construction||IP40||IP40||IP67 (Waterproof)|
|Range of operating temperature||0 to 80 °C (non-freezing)|
|Contact ratings||5 V DC to 24 V DC,
10 mA (20 mA maximum) resistive load
Cyclic test with an Agilent laser measurement system
Repeatability is measured with the Agilent laser measurement system that has a precision of 1/100,000 mm.
Compact as it is, the switch can achieve 1 μm repeatability (in the case of the high-precision type, 0.5 μm repeatability).
Endurance tests repeated as many as 10 million operations or more
Endurance tests were repeated over 10 million operations to ensure an durability of 3 million operations.
Despite being a mechanical type, the switch has an assured durability of 3 million operations.
The voice of engineers
We have received many comments from engineers.
We use the vacuum-compatible type for positioning in the solar panel manufacturing process.
Previously, there were no sensors usable in a high vacuum and we were forced to conduct positioning with optical sensors from outside the system via viewports.
Now, using this switch, we don't need viewports any more.
In this way, costs have been reduced and the price competitiveness of the system has increased.
Medical equipment engineer
We have employed the radiation-compatible type for the positioning of irradiation mechanisms for radiation therapy equipment.
Previously, radiation accelerated the degradation of optical sensors and the costs and labor required for replacement were considerable. After the introduction, however, no labor is required for replacement and the equipment operation rate has improved.
We have employed precision positioning switches to confirm the opening and closing of the disk brakes of elevators.
The switch can precisely detect 0.5 mm slight movements without hysteresis and has enhanced the safety of elevators.
Brake problems have been reduced and inquiries from other industries have increased.
Medical equipment engineer
We have employed precision positioning switches for the balancing of microscopes used in neurosurgery.
The switch supports the inosculation of 0.05 mm blood vessels at a micron level.
The high precision of those microscopes has gained a good reputation in this field and many medical institutions around the world have decided to introduce them. Its small size is also very helpful in incorporating it into the equipment.
Other product lineup
There are a variety of series depending on the application.
For details, please request the postage-free Precision Positioning Switch General Catalog.
Ultra-small type PT series
M5 × 17 mm, 1 μm repeatability
World's smallest class
Mini stopper-attached STM series
300 kg Static load resistance, 8 × 8 mm
Attachable to a robot fingertip
High-precision type MT series
0.5 μm repeatability without amplifiers
Usable in adverse environments caused by water and oil
Heat-resistant type HT series
Usable at an operating temperature of 200°C
Medium-precision type CS series
Compact design of M5 minimum
Best selling positioning switch
Vacuum-compatible type GN series
Usable in a 10-5 Pa-class high vacuum
If you would like to have a General Catalog (postage-free), please request it with the Contact Form.