Ointment milling machines not only need to ensure that the end product is extremely smooth but they also need to be able to be easily cleaned, to avoid contamination.
A UK company called Torvine has been trying to produce the ultimate milling machines to solve both these issues. The result is the Dermamill 100, which has become the tool of choice for compounding pharmacists across the world.
Removable rollers mean the mill can be made lab-clean in minutes. Speed control and a roller guide locking mechanism means ointment milling can be controlled with maximum efficiency. The operator can control the two gap sizes manually. Product fineness can be reduced to 20µm (20 microns), and lower sizes are possible with more passes through the mill. Particles are not crushed (which could result in clogging and the opposite result). They are sheared by the differential speeds of the rollers. The ointment passes through both gaps and receives shearing forces, resulting in particle size reduction, particle dispersal, and homegenisation. The finer the ointment, the more take-up of the active ingredients occur on the skin, which maximises the benefit to the patient.
Torvine contacted Maxon Motor UK when it needed a reliable, quiet motor to drive the ceramic rollers. Its machine is now manufactured using the Maxon EC45 50W flat brushless DC motor, customised for this application with a longer flexprint cable, and the modular DEC24/2 DC motor controller. Speed control is especially useful when milling thin substances and the Dermamill offers 20 speed increments, ensuring the operator has precise control.
The DEC 24/2 module is specifically designed for OEM applications. The chip is incorporated as part of the PCB design with a standard pin pitch, to offer ultimate flexability in form factor for the OEM design. This way the motor controller forms a proper integrated solution at an attractive price. The simple 1Q brushless DC motor controller is simple in operation but offers essential features such as; closed loop operation, fault monitor output, blockage protection and current limiting to prevent damage to the motor, the mechanics or the operator, also under voltage/over voltage and thermal overload protections.
