No drawing unfortunately, but here's how it works.
You have a lube tank at the back of the machine, with a motor that runs a cam. As the cam turns it lifts a handle that pumps lube oil. The handle is pumped every 32 minutes of spindle run time.
When the handle is pumped all lube lines in the machine are pressurized to approx 20-40psi. Pressure will remain for anywhere between 5 and 10 minutes. At all points where lube is required - ballsrews, linear rails, etc there is a restrictor valve that slowley allows the lubrcation to flow through to lubricate properly. If cheap/ bad lube oil is used, then these restrictor valves can get blocked up and will then need to be replaced.
The spindle is lubricated by the pressurized oil - mixing with compressed air, then piped up to the spindle giving air cooling and lube simultaniously.
There is a pressure switch just behind the lube tank so the machine knows whether:
1 pressure is there or not
2 If there is a leak in the system
3 If the system is totally blocked
There are two filters in the system.
One is a suction filter inside the lube tank.
The other one differs in location depending on the age of the machine.
Pre 2004 the filter is located to the left of the lube tank - and after 2004 it is located inside the tank.
Hope this helps