ICAR Technical Series no. 7 - Nitra Proc.

Vibrations and vacuum stabilityWe assume that cows are at least as sensitive to vibrations as human beings.Therefore, it is obvious that, given the above mentioned values, the cowsdo not like to be milked in the milking parlour or that they do not releaseall their milk.Figure 1 shows how vibrations can be reduced by modifying theinstallation.3,5003,000Acceleration in m/s 22,5002,0001,5001,0000,5000,0001.25Hz2.0Hz3.15Hz5.0Hz8.0Hz12.5Hz20Hz31.5Hz50HzBefore the modificationFrequency in Hz80Hz125Hz200Hz315Hz500HzAfter the modification800Hz1.25kHz2.0kHz3.15kHz5.0kHz8.0kHzFigure 1. Vibrations measured in the milkline.Transfer of thevibrations tothe vacuumsystemThe major aim of every milking system is to reach a stable vacuum fromthe air pipe to the claw and the top of the teat. The vibrations of theconstruction of the milking parlour are also transferred to the vacuumsystem and intensified by wrong installation or additional devices(pulsator, regulator valve). Figure 2 and 3 illustrate the impacts of thetechnical modifications on the vacuum stability in the air pipe and themilk line respectively.114Conference on "Physiological and technicalaspects of machine milking"