Measuring electrostatic charge produced by combing hair - using counter measuring output of voltage to frequency converter connected to copper wire attached to comb

摘要

In order to compare relative characteristics of cosmetic products such as shampoos, the electrostatic charge produced by combing after treatment is measured. This is achieved by attaching an electronic counter to the comb. The comb (1) of a copolymer material has a thin film of copper deposited on it. This supports the attachment (2a) of a copper wire (2) in an insulating sheath. The wire is connected to ground via a high value resistor (7) in a counter circuit (3). A voltage to frequency converter (6) provides pulses whose frequency is proportional to the number of millivolts of input voltage applied to its input. The output is connected to a pulse counter (8) which produces a numerical reading for display (9) of the pulse count.