Lubrication in the automotive industry
Grease and adhesive dispensing systems guarantee the quality of electric parking brakes
Modern vehicle concepts typically feature systems designed to further enhance the driver’s safety and comfort, whilst the growing need for manufacturers to differentiate themselves from their competitors has also prompted the development of new ideas. The electric parking brake, which replaces the conventional mechanically operated handbrake, satisfies the increasing trend for additional functionality, comfort and space in the passenger compartment. KÜSTER ACS originally joined forces to develop an electric parking brake in collaboration with Renault, but now the company also supplies other manufacturers including BMW Mercedes, PSA, Toyota, Subaru and Land Rover. More than 1 million units have now left the KÜSTER plant in Ehringshausen, Germany.
Custom-made solutions by DOPAG
Part of the process of manufacturing the electric parking brakes involve applying metered shots of grease to a mechanism within the housings of the brake units in order to lubricate and thus reduce the frictional forces on a splined shaft. The grease is supplied in 30 litre size containers and is fed to the application point by twin DOPAG P30 drum pumps. The pump system is designed to ensure that the supply of grease to the brake assemblies is always uninterrupted, by the use of an automatic changeover mechanism that switches supply to the standby pump when the first drum of grease becomes exhausted. The grease is then fed to the application point, where it is precisely metered onto the component, by a DOPAG chamber metering valve. The system concept was designed to accommodate the nature of this special grease, which tends towards separation if left under pressure for long periods of time. To avoid this potentially damaging effect, the system automatically relieves the internal pressure when not in use.
Bonding with DOPAG dispensing valves
Further on in the production process, the cover of the brake unit is bonded onto the housing with a single component adhesive. The adhesive is also fed to the dispensing point by twin DOPAG P30 drum pumps, featuring the automatic changeover system. A gear pump then meters the adhesive to an automatic dispensing valve, whilst a small 6-axis robot grips the cover and manipulates it beneath the dispensing valve. An in-line flowmeter checks the accuracy of the flow rate, thereby ensuring perfect results on every occasion.
Electrical parking brakes are of course, a safety-relevant product and as such, quality requirements are extremely high, something that is offered as standard by DOPAG.