Now that I've got a rare spare moment here we go:
Here are some pics from a shed that was actually finished while I was there.
First up we have a general view of the rotating platform,
this one is what is known as an 80 Bail platform, meaning that when full, it will hold 80 cows:
Next up, we have a shot of the receiving can on the right and the sanitary trap on the left- this removes foreign matter from the top of the milk froth before it goes to the milk pump to the left, this is a 2.2kW motor, controlled by a VSD that is in turn controlled by a probe in the receiving can:
Here is a shot of the 24 Volt AC power supplies and milk pump controller, on the other side of the milk pump controller, are the vacuum controller and the master controller for the electronic cup removers:
Next we have probably the most critical component in the whole dairy shed, it is known as the Orbiter Gland, as well as sending vacuum to the cans, and milk out to the pump room, it houses a set of 8 brushes and slip-rings (3 phase 400V + Neutral and 3 control wires) to run the plant under the platform.
This gland must
be in the absolute centre of the platform ring, if it is mis-aligned by even a millimetre or so, it can cause the pipe work to twist as the platform turns.
Above the Orbiter, is the Wash gland, this enables the milking gear to be washed as the platform is still turning, a real time saver:
From this next image, we can see that every bail has 2 rams, the top one is for operating the bail gates, seen in the first picture, the second one below it is what is known a a cup remover ram:
How this system works is, like this, every cow is monitored by a sensor on each milk tube that senses when the cow stops giving milk, the sensors look like this:
Now, when the cow stops giving milk, the cups drop off the cow and the bail gate behind it lifts up by vacuum.
One added bonus of this is that the cup remover ram will lift the cups up off the platform, to prevent them being stood on by the cow or contaminated by fecal matter.
If the cow still has not stopped giving milk by the time it has reached what is known as "cups off", the cow will be retained by the bail gate and will go around again.
Now, here is what drives these platforms, there are often, depending upon the size of the platform, 2 or 4 motors driving the thing, BTW, there is another drive unit on the other side of the track:
These units are also controlled via a VSD, a platform is not something you'd want to have to start Direct-On-Line
A look out at the yards, sorry no sunrise this time, but these ones are actually finished.
What we have here is two backing gates and a top gate, the backing gates are driven by water pressure, with the added advantage, that it cleans the yards at the same time as they are moving.
The top gate is used to move cows towards the shed.
You might notice small chains hanging from the bar on it, these are charged with an electric fence energiser, that is modified to only give the cows a mild shock, not like out in the fields:
Here is a look at the power unit for the backing gates themselves:
OK, that's about it for now, if anyone has any questions at all, please just ask.