New commercial vehicle models are aerodynamic, safe, economic and the result of intensive development work. With its extensive filter design and manufacturing expertise, MANN+HUMMEL was able to become a supplier of air cleaners for a new cabin generation.
Economy and safety are right at the top of the list of requirements for modern commercial vehicles. As a result, a Swedish producer focused on safety concepts and consumption when redesigning its truck series. According to the producer, an improved powertrain and enhanced aerodynamics enable the new generation of trucks to achieve a five percent reduction in the consumption of diesel.
The Swedish producer was particularly interested in an intelligent air intake and air cleaner concept. The air intake is positioned at the front of the vehicle below the windscreen. Four attachment points fix the air cleaner in its upright position in front of the right front wheel behind the driver‘s entry to the cabin. The dirty air duct is inserted onto the side of the air inlet of the air cleaner. The air cleaner comprises a total of just three parts: the plastic housing in PP-GF30 consisting of two parts which are mirror welded, the filter element, and the service cover which is screwed to the housing with four self-tapping screws. This enables the maximum filter surface area to be realized in the available installation space.
The large surface area of the round filter element serves to direct the air with the lowest possible pressure drop whilst reliably separating the dust particles. The clean air port of the cover is connected via a decoupled clean air duct to the engine using a clamp. In order to ensure the optimum air inflow to an air flow meter fitted in the clean air duct, a honeycomb grid is integrated in the clean air outlet of the air cleaner. Besides an economic solution and compact dimensions, an easy cleaning concept for the air cleaner housing was requested.
To fix the air cleaner a specially developed sheet metal nut with a metric thread is used which is simply snapped into the intended holding positions. When the product is screwed on at the customer a metal to metal contact is formed which prevents a relaxation of the fitting. As a consequence, the air cleaner is securely fitted over the whole life of the vehicle.
In order to change the filter the cabin is tilted. The servicing is easily and safely performed using a patented system from MANN+HUMMEL. The clean air duct can remain attached to the cover. After loosening the self-tapping screws it can simply be lifted from the filter housing and the filter element can be removed from above. This exposes a cleaning hole that enables easy dirt removal from the bottom of the housing. The insertion of the new filter element is mechanically guided so that it sits securely in the right position. This ensures that the cleaning opening is tightly sealed by the PUR foam on the underside of the filter element.
The round filter element also includes a proven radial seal and glue thread reinforcement which stabilizes the pleats so that, even at higher humidity, the risk of restricted air flow due to collapsed pleats is eliminated. The center tube in plastic makes the element robust and resistant to negative pressure. With this solution MANN+HUMMEL provides an economic, robust and service-friendly air cleaner.
In addition to air cleaners for the new vehicle generation with front air intake, MANN+HUMMEL also supplies dust pre-separators for vehicles with the air intake behind the cabin for applications with high dust separation requirements such as construction site vehicles. Despite its low pressure loss the high dust pre-separation efficiency of the dual cyclone pre-separator enabled the specialists from MANN+HUMMEL to considerably extend the service life of the air cleaner fitted downstream.
The basis for this development was a design which has already successfully proven itself on the market in a different application. In order to fit within vehicle design, MANN+HUMMEL in consultation with the customer, integrated the cyclone into the intake channel of the cabin. This integration required adjustments in comparison to the previous design in particular with regard to the dust discharge. In addition to two dust discharge valves pointing downwards, an interface to the bellow, which compensates the relative movements of the cabin to the air cleaner was incorporated. Close alignments for the fitting of the dual cyclone prevents potential rattling during operation which might be caused by an excessive assembly clearance. Due to the design requirements, the dual cyclone itself is not visible but continues doing its dusty job behind the scenes.