Gear Pump Volume Formula

[Bob1uk]

Could some kind soul point me in the correct direction please.
I need to find the capacity of an automotive transmission gear pump, the engine driver gear measures 2.364" driven gear=1.694" gear width=.472" and dimension between centres =1.574"

The formula I have is for gears of equal OD

Thank you for any & all advice
Bob Ryan

 

[hydtools]

Figure the ratio of the gears. 2.364/1.694 = 1.396 = the speed increase driver to driven.
Doesn't say anything about the output flow of the pump. Need to know the displacement of the pump, in^3/rev.
Need to know the speed of the driver gear.

Ted

 

[Bob1uk]

Thanks for your reply Ted. Driver gear has 28 teeth & driven has19 teeth. Input RPM is from 500 to a max of 6000 RPM. It is the displacement of the pump that I am trying to calculate. I have included a picture, the large gear is driven by the engine. Hope this helps in helping me.

 

[hydtools]

Better yet with the tooth count. Speed ratio is 28/19 = 1.47 driver to driven.

Pump speed will be from 735 to 8820 rpm.

Can not calculate pump displacement from speed or gear ratio unless you know pump flow at a pump speed.

Ted

 

[sreid]

As an approximate solution, estimate the volume of each geartooth "Pocket." Then how many pockets dump their volume each second?