MOBIO booth No. : North facility 2nd floor 116


Product line

Dial thermometers

Transformer protective relays

Fluid filled thermometers


Yoshio Hyoda

Description of business

Since their founding, Hyoda has developed and produced thermometers and other measuring devices. Their products are used in a wide range of fields from heavy machinery, atomic power and petrochemical plants to ships and the home. They are also employed in light industry such as factories manufacturing textiles, dyes and food processing.

Products and Technologies

Industrial Dial Thermometers, Protection for Heavy Machinery

Thermometers and Pressure Gauges from Hyoda Quality and Performance before their Time

Industrial dial thermometers and protection devices for heavy machinery

Hyoda creates and develops thermometers, pressure gauges and other measuring devices, striving to ensure their customers are always satisfied.
Today, the efficient use of energy and the effect on the environment are serious issues that industry must consider. Measures are currently being implemented on the global level to fight global warming, and heat management plays an important part in those measures.
Hyoda thermometers are important tools for heat management, used everywhere from the home to atomic power plants.
Hyoda lineup of instruments provide protection for a range of applications from power generators and transformers to power distribution equipment, ensuring high-quality, stable power supply in our daily lives and for industry as well.

Protection Relays for Power Generators, Transformers, Distributors

Hyoda makes protection relays to ensure generators, transformers and distributors can perform safely day in and day out. When there is an anomaly during operation, the protection relay immediately detects it and sends out a warning to prevent a mishap.

Protection relay products include temperature relays for monitoring temperatures, oil flow indicators for monitoring oil flow, dial oil gauges for monitoring oil quantity, impact gas pressure relays for monitoring gas pressure, impact oil pressure relays for monitoring oil pressure, leak detectors for monitoring oil and water leaks, Buchholz relays for monitoring oil flow and the presence of gas, discharge devices for monitoring gas pressure and pressure discharging for normalization, and gas pressure switches for monitoring gas pressure.

Hyoda began selling their protection relays to Japanese electric companies and now supplies electric companies around the world, helping to improve safety.

Hybrid Temperature Transmitters

The hybrid temperature transmitter combines a mechanical dial thermometer with a temperature sensor and its temperature element (such as a resistance thermodetector or thermocouple) integrated with the temperature sensing part, making it possible to issue worksite instructions even when remote.

In the past, the dial thermometer and remote transmission temperature sensor were supplied as separate tools at the worksite, but the hybrid temperature transmitter combines two desirable features in one unit.

The first desirable feature is decreasing the number of connections for the temperature sensor part from two locations to one.
The second is placement of the temperature sensor wire through a flexible tube along with the dial thermometer pipe to the instruction unit of the dial thermometer, so the temperature sensor wire for the user can be connected to the instruction unit of the dial thermometer.

The hybrid thermometer transmitter thus decreases costs from the purchase cost to the cost for installation, a great benefit.

Corporate Profile

Corporate name
1-6 Izumoi-Honmachi, Higashi-Osaka City, Osaka, 579-8034, Japan
Yoshio Hyoda
Founded / Established
1917 / 1953
Company URL

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33,000,000 yen

Patent, Design Right, ISO9001