Oil pumps

[winchester1892]

In July's issue there is a full page spread by Ed Hughes on how gear-type oil pumps work. This shows the flow of oil going between the gears, through the meshing area.

I believed that (as in Roots blowers) the pumped fluid is entrained between the outer part of the rotating parts and the casing, the opposite of the way the direction of rotation is illustrated in the article.

Confirmation of which is correct would perhaps be helpful.

[Richard Moss]

Certainly your understanding of it fits with my understanding of oil pumps and hydraulic pumps