Distributor piston — general information (Escort 4)

From the rotary pump, the fuel is pumped under pressure to the fuel pump. In the pump, on the same shaft as the rotary pump, there is a distribution piston. It is the main unit of the pump and performs the functions of filling and injection. This happens as follows: when filling, the piston control spline is opposite the inlet hole. Fuel from the rotary pump under pressure enters the free cavity of the piston and flows into the free cavity of the piston and into the space in front of the piston. The distribution piston rotates (via a gear at a speed equal to half the engine speed), and the filling space closes again.

There are also two other units involved in the pump operation. The distributor piston is connected to a disc with 4 cams. This disc cam rotates around a fixed support which, in order to reduce friction, has 4 rollers installed at the same distance as the cams on the disc cam, i.e. the disc cam rotates on a roller ring. When the cams roll on the rollers, the disc cam together with the distributor piston is pressed forward in the axial direction. This occurs exactly at the moment of injection, at which the next hole in the piston coincides with the outlet channel for the injector. Fuel can thus be supplied to the cylinder in which compression occurred. When the distributor piston moves forward, the volume in front of the piston simultaneously decreases, and the fuel under pressure is additionally compressed and injected into the injector.

With further rotation of the fuel pump, the distribution piston returns back and a new portion of fuel enters the piston cavity from the filling hole and the process is repeated.

The original can be found on this resource www.FordBook.ru