Gearwheel pump for high pressure fuel pump has housing with gear wheels and groove having first and second sections with different spacing at bottom from tooth tips producing narrow gap for better pump action

摘要

The pump has a housing (18) with two gear wheels (14, 16) and a groove (22) on the pressure side. The groove has a first section (24) extending from the pressure side and in which the bottom of the groove is slightly spaced from the tip of the teeth of the gearwheel. It has a second section (26) adjoining the first and in which the bottom of the groove has maximum spacing from the tooth tips. The first section extends over a smaller angular region than the second section and the groove overall extends over an angular area greater than the angular distance between two teeth (20).