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Parts of a Milking Machine

Charles Pearson

Milking machines extract milk from cows. These machines cause less stress for the cow and damage teats less often. The milking machines also reduce the risk of inflammatory infection. While older milking machines often caused damage to the cow teats, the invention of the pulsator in 1980 lead to safer automated cow milking. The latest milking machines use computerized technology to regulate milk suction.

Teat Cups

Milking machines automate cow milking and also reduce cow teat injury.

The farmer attaches teat cups to the cow's teats for protection. The vacuum tube creates the suction that draws the milk out of the cow's teats. The milking machine has four teat cups for the four teats that cows have. They have an inner rubber liner and an outer metal shell. The teat cup has a thin inner rubber liner and a thicker rubber liner within the tube. This teat cup has two chambers: one inside the liner and one between the metal shell and the outside liner.


The milk leaving the cow's teats travels down the claw. The milk then travels from the claw to the milk tube. The vacuum tube provides constant negative pressure that draws the milk from the gland. When the vacuum tube enters the rest phase, the air entering the tube collapses the rubber liner, massaging the teat and maintaining the blood flow. The teat-end vacuum has 11 to 12 inches of mercury. Incorrect vacuum settings, flooded milk lines and uneven milk-out quarters create air leaks that can cause teat-end vacuum fluctuations. Farmers can identify this phenomenon by a vacuum sound.

Milk Tank

The suction created by the vacuum brings the milk to a collecting bowl at the bottom of the claw. The milk then flows through a tube to the milk tank. The farmers usually house the milk tank in a separate room from the rest of the milking machine.


The milking machine automatically turns on and off via the pulsator. The pulsator ensures that blood and lymph do not accumulate near the teat, causing damage to the teat. Some milking systems automatically remove the teat cups after the milking machine has extracted all of the milk so that the machine does not damage the cow teat. The farmer should clean the pulsators with regularity to ensure that they function properly.


Milking machines use advanced computer software to keep track of the cow milking and to also control the milking machine. The farmer can look at the logs and determine what's wrong with the milking machine. When the flow of milk slows down, the milking machines automatically slow down the suction and detach the teat cups from the cow's teats.