Thermoelements constitute the basic part of all of the wax type products in which both functions of temperature sensor and actuation coexist.The wax sealed inside senses ambient temperatures and expands, which leads to transfer of the piston(lift length). Various use is possible.


The thermostat is an actuator which alters variation of temperatures into linear movement. Used for temperature control of engine coolant,etc. As home devices, used for temperature control of hot water of showers, thermo ventilators,etc.

Service temperature:-30℃~+120℃  
Lift length:8mm  Load:68.6N


Operates sensing variation of ambient temperatures Powerful output Compact
Unnecessary of electricity Sustainable in variation of environment Silent

Operates sensing variation of ambient temperatures

The thermoelement operates in compliance with variation of temperatures. It extends its piston in high temperatures, while shortens in low temperatures.

  1. Extend sensing high temperatures.
  2. Shorten sensing low temperatures.
    (Some mechanism is necessary to shorten the piston)


The lift length of the piston in thermoelement varies with variation of temperatures as show left caused by expansion of paraffin wax enclosed.

  • Expansion area of solid paraffin wax.
  • Expansion area of solid-liquid paraffin wax.
  • Expansion area of liquid paraffin wax.

By changing characteristics of paraffin wax,free designs for the following features will be possible.

  • Temperature to start extension.
  • Slant of extension.
  • Maximum length of extension.

Powerful output

Strong output power will be expected.



Thermoelements combine both functions of temperature sensing and output,which saves costs compared with an electric system.

Examples of thermoelements Naturally, powerful output will be expected by large ones.

Unnecessary of electricity

As heat expansion of paraffin wax operates thermoelements, an electric power supply is not necessary. Therefore, it can be mounted even on such location where power supply can not be expected or hard places to use electricity due to around water.

Sustainable in variation of environment

The thermoelement is sustainable in hard variation of environment as easily imagined from the use in automobile engines for cooland circuit. Service temperature is wide enough of -40℃~130℃ compared with motors.


Completely no sound of operation different from motors.


The thermostat is, as an example of applications for automobiles , a flow control valve built-in the coolant circuit of automobile engines. Following illustrations show an actually example of a thermostat in the plastic housing mounted on some automobiles.

The thermostat is built-in the coolant circuit of automobile engines and operates to keep the coolant temperature constant.
Its operation is as follows.

The thermostat shuts the coolant passage of radiator while coolant temperature stays lower at which temperature the piston of thermostat does not start to extend.

Coolant flows as shown by arrows.

As the engine is getting warm and a coolant temperature reaches such temperature as thermoelement begins to extend, the element opens the valve of thermostat.

Then the cooled coolant from the radiator passage flows into the engine.

As the rise in temperatures of coolant flowed into from the engine, the valve opens furthermore and lots of the cooled coolant flows in.

Thus the thermostat operates in keeping temperature of the coolant flowed into engines constant.


Examples of equipment

Fixed mounting
The left illustration is an example of equipment mounted fixedly.

Sliding mounting
The left illustration is an example of equipment, the body of thermoelement moves instead of the piston.

☆Suggesion on equipment☆

  1. Setting of return springs.
    Some action, for example by spring or something like this , is required for thermoelement to shorten its piston/element from the state of extension, otherwise it will not be back to its former position.
  2. Positioning of sensing part of temperatures near the place to be monitored.
    The thermoelement detects temperatures by the sensing part(shown as pink color above). Just equip thermoelements as water, air or oil flow onto the sensing part.