top of page


The RD1 pump has successfully solved a number of technical challenges faced during the design of an automated cocktail dispenser. The dispenser, designed for commercial applications, uses the unique patented rotary diaphragm technology offered only by Charles Austen Pumps.

​Previous designs using a diaphragm pump had failed as the valves could not cope with the fruit pith and seeds found in high quality smoothie mix which resulted in unreliability and frustrated customers.

​Switching to patented rotary diaphragm technology solved this problem while allowing the same pumps to be used to dispense concentrated syrup and bag in box soft drink mix.

​The RD1 pump has a range of options for OEM vending applications including BLDC and Stepper motor options and food grade materials suitable for European or NSF approvals.



Drinks vending is a market where pump selection is critical in order to avoid costly service call-outs, messy leaks and expensive downtime. The technology used to pump the beverage is key

to how reliable the entire machine will be in service and the reputation of the manufacturer. 

​Until recently, beverage dispense relied on just a few pump technologies; mainly peristaltic and gas driven. Both methods of pumping have their disadvantages. Peristaltic pumps will eventually suffer from tubing splits or gearbox failure. The tubing has no memory, so the amount of liquid being dispensed at the start of it’s life is unlikely to be the same after a few thousand vends. Air driven pumps by definition require an air or CO2 supply, rather than being directly driven. For smaller bench top machines which may be located away from compressors or bottled CO2, this presents an expensive and lengthy installation process.

​Charles Austen Pumps introduced the patented Rotary Diaphragm Liquid pump into the market over 15 years ago, primarily for workplace brewers where the ability to pump both hot or cold liquids was required, along with a tolerance of lime-scale

or other particulates. 

​Since then it has been used for many drinks dispense applications where a reliable food grade pump is needed. 


Charles Austen Pump’s patented rotary diaphragm pump, coupled with a DC Motor, is now being used to pump juice concentrate (syrup) from bag in box and deliver to a dispense font. The syrup is mixed with cold water drawn from a mains supply and dispensed as a post-mix fruit drink. The number of flavours offered by the drinks dispenser determines the number of pumps used.


Different flavours require different mix ratios, so the RD5 pump technology combined with DC drive allows the flow rate of the juice concentrate to be easily controlled by varying the DC input voltage.


The manufacturer of the juice dispenser chose the Charles Austen Pumps RD5 for their reliability and superiority over other pumping technologies such as peristaltic, air driven, and standard diaphragm due to their ability to draw the more viscous concentrates over longer distances.


The RD5 has excellent self priming capabilities and an ability to move cold or hot liquids of varying viscosities which have made it suitable for this type of application.


The RD5 with DC motor pump has only two wetted parts; santoprene and polypropylene, both of which can be supplied in food grade. Therefore, the pump is also suitable for moving hot liquids which has led to its use in workplace brewers for hot and cold drinks dispense applications.

bottom of page