Types of Oxygen Sensors
Oxygen sensors have played and are still continuing to play an indispensable role in a vehicle. It would be good to know more about them. Did you know that there are different types of oxygen sensors? Below are five types which would definitely expand your knowledge about the way a car works.
1. unheated thimble
This was introduced by Bosh back in 1976. The main purpose was for the feedback regarding fuel control where automotive engines are concerned. “The zirconia ceramic ‘thimble’ is encased in a protective tube which extends into the exhaust manifold. Slots in the protective tube allow hot exhaust gases to reach the thimble. Reference outside air for the interior of the thimble comes from a hole in the sensor shell, or through the wiring connector.” Relying on the heat of the exhaust gases to be able to arrive at the operating temperature, the unheated oxygen sensors might cool off during the time the engine is idle. Then it will go back to the set air/fuel ratio setting. This kind of sensor usually comes with one wire connector although some may have two of those.
2. heated thimble
It was introduced in 1982 by Bosch, a heater element was added to this certain type of oxygen sensor. This made it possible for the sensor to achieve an operating temp. within 30-60 seconds instead of waiting to be heated by exhaust gases. Its heater has a separate electric circuit. You would be able to tell apart this type of oxygen sensor from the others because it has three or four wire connectors.
3. heated titania
This was introduced in 1982 by Bosch, a heater element was added to this certain type of oxygen sensor. This made it possible for the sensor to achieve an operating temp. within 30-60 seconds instead of waiting to be heated by exhaust gases. Its heater has a separate electric circuit. You would be able to tell apart this type of oxygen sensor from the others because it has three or four wire connectors.
4. heated planar
This type of sensor was brought in last 1997 by Bosch. There are various materials this oxygen sensor used, such as electrodes, heater, insulation, and a laminated flat strip of conductive ceramic. It is harder to contaminate and is more compact and delicate. It brings the temperature needed in ten seconds by the heater, which expends a smaller amount of electricity.
5. heated wide-band
This type is taken from the planar design, with Bosch adding the capability to gauge the air/fuel ratio. As opposed to the back-and-forth method of the other oxygen sensors, the wide-band oxygen sensor would be able to produce a signal which is directly proportional to the ratio of the air/fuel. Being able to give precise measurements, this type of sensor makes it possible to add or subtract fuel as needed.
source: protoworks.com