Pierburg develops OE vapour pump innovation

Wednesday, October 25, 2017

Automotive systems and components specialist Pierburg, has once again demonstrated its OE credentials and track record of innovation with the development of a new compact electric pump for fuel vapour.

Today’s strict emission standards means most cars now have a system where by fuel vapours are trapped in an activated carbon canister mounted close to the fuel tank. This canister needs to be regularly purged and to do this Pierburg has developed an innovative pump that works even without the intake pipe vacuum which was necessary until now. The electric pump is the first of its kind and will go into series production in 2018.

EU legislation restricts the amount of volatile hydrocarbon compounds that may exit a vehicle's fuel system. Activated carbon therefore collects the fuel vapours inside a canister, binding them until they are burned in the engine. The canister's capacity for storing these compounds is, however, limited and hence fresh air must be regularly injected in order to avoid saturation. Under all engine operating conditions in which the additional volume of fuel vapours is tolerable for the engine and the combustion process, a valve therefore opens to allow the vapours to escape into the intake manifold or flow in the direction of the turbocharger.

In the past, the vacuum arising when fresh air was drawn into the engine was sufficient to draw the fuel vapours into the engine and, at the same time, allow fresh air to flow into the activated carbon canister. Today's engine generations lack a sufficient vacuum and require a solution that actively helps clean the canister. Pierburg's new electric vacuum pump offers such a solution that at the same time takes account of the increased significance of onboard diagnosis while checking for any leakages.

The pump design offers a fast response and it is lightweight due to use of plastics. Innovative active cooling of the electronics improves the pump's thermal resistance and this cooling also ensures that the new pump withstands the arduous conditions within the engine compartment. An integrated sensor reports system pressure to the monitoring unit.