⚙️ Milking machine

A milking machine milks a cow using a vacuum, that is, lowered pressure. A teat cup is put on each of the four teats. Inside the cup is a soft rubber or silicone tube called the liner. A steady vacuum of about 32–42 kPa is kept under the teat. A separate part, the pulsator, squeezes and releases the teat 50–60 times a minute. It is like a massage: the teat gets a rest, and blood does not build up in it.

A cow is usually milked in 3–5 minutes. When the milk stops flowing, a modern machine takes the cups off by itself. The milk travels through stainless steel pipes, through a filter and a cooler, into a tank. No human hand touches it.

The first milking machines appeared at the end of the 19th century. In the early 20th century the machine sat right on top of a milking bucket, which was emptied after each cow. Later came milk pipelines and milking parlours. Milking robots have been on sale since the early 1990s: the cow comes to be milked on her own, the robot recognises her by her tag, finds the teats with a laser sensor and puts on the cups.