Bosch VE Distributor Pump Design and Construction

By 13 March 2017

The distributor pump’s drive shaft runs in bearings in the pump housing and drives the vane-type fuel-supply pump. The roller ring is located inside the pump at the end of the drive shaft although it is not connected to it. A rotating-reciprocating movement is imparted to the distributor plunger by way of the cam plate which is driven by the input shaft and rides on the rollers of the roller ring. The plunger moves inside the distributor head which is bolted to the pump housing. Installed in the distributor head are the electrical fuel shutoff device, the screw plug with vent screw, and the delivery valves with their holders. If the distributor pump is also equipped with a mechanical fuel shutoff device this is mounted in the governor cover.

The governor assembly comprising the flyweights and the control sleeve is driven by the drive shaft (gear with rubber damper) via a gear pair. The governor linkage mechanism which consists of the control, starting, and tensioning levers, can pivot in the housing.

The governor shifts the position of the control collar on the pump plunger. On the governor mechanism’s top side is the governor spring which engages with the external control lever through the control-lever shaft which is held in bearings in the governor cover.

The control lever is used to control pump function. The governor cover forms the top of the distributor pump, and also contains the full-load adjusting screw, the overflow restriction or the overflow valve, and the engine-speed adjusting screw. The hydraulic injection timing device is located at the bottom of the pump at right angles to the pump’s longitudinal axis. Its operation is influenced by the pump’s internal pressure which in turn is defined by the vane-type fuel-supply pump and by the pressure- regulating valve. The timing device is closed off by a cover on each side of the pump.

The subassemblies and their configuration
1 Pressure-control valve, 2 Governor assembly, 3 Overflow restriction,
4 Distributor head with high-pressure pump, 5 Vane-type fuel-supply pump, 6 Timing device,
7 Cam plate, 8 Electromagnetic shutoff valve.