Caffeine addicts will welcome coffee machines that employ gear pumps from Johnson Electric, a Hong Kong-based company with offices in the U.S. The new GP pump series for beverage dispensing applications promises several performance advantages, most notably dispensing speed.
These gear pumps are certified by NSF International, in Ann Arbor, Mich., for safe food processing. They can deliver hot liquids up to 95 degrees C, but also works with cold liquids.
Traditional solenoid pumps cannot be used to pump hot liquids due to the effects of heat on the coil. In coffee machines, water must be pumped cold before being heated.
For high-output machines, such as those found in office environments, the use of gear pumps is said to enable hot water preheating and thus energy savings. The ability of gear pumps in handling hot liquids also has implications in the cleaning step that is sometimes employed between dispensing of different drink types, especially when milk is added, as hot water can be used in the cleaning process.
With an optional electronic controller, Johnson Electric’s gear pumps can deliver variable flow rates to dispense different types of drinks to suit various tastes. The four pumps in the series are capable of dispensing between 560 and 3,000 ml/min of beverages.
The NSF gear pump product line is designed with an isolated gear pump head that generates no temperature rise when delivering cold beverages. The NSF pumps are operated by low-voltage DC power to enhance safety in the event of liquid leakage and reliability of beverage machines compared with higher-voltage AC-powered pumps.
Faster flow rates have been realized through faster gear rotation, as well as improvements in pumping efficiency through design modifications. The gear pump head is molded from a proprietary food-grade plastic developed by Johnson Electric, while other pump components are made from food-grade stainless steel.