Gear Box Ratio, Speed, and Torque

We got an app for that.... http://www.androidzoom.com/android_applications/productivity/gear-cam_tppq.html

If you work out the ratios, the diameters will take care of themselves.

How much work will the system be required to produce?

What is the expected output?

Only if the 1500rpm output occurs at 4475rpm input .... this is implied but not specified in your post.

Yes correct, the 1500rpm output occurs at 4475 rpm input.

I have managed to work out some of my problem. Gearbox ratio and torque ratio are the same ( I did not no this ). I also found out that the input rpm is 2467 and not 4475 like i thought.

So if you divide the output torque by the input torque that is gear box and torque ratio.

Based on this I no I have a ratio of 1.65 and input torque of 390nm, 1.65x390 = 643.5nm output.

Also if you divide input and output rpm you get the same figure 1500/2467 = 1.65.

So now I know the ratio 1.65 is there any formula to work out gear diameters.

Sorry for the miss leading information and thanks again for your time.

What is input power, is it electric motor or something else at 2467 rpm? You should know the motor kW or power to be transmitted to decide pinion diameter and its width. Gear diameter can be obtaines multiplying by gear ratio.

If you know the effective diameter of one gear, then you can find the effective diameter of the other. (Both the diameters and tooth counts will be in the same ratio... which is the same as the torque ratio of the gear ratio.) The physical size can be different form one gearbox to another, however: 10 mm X 16.5 mm, 20 mm x 33 mm... etc.

To calculate the actual sizes of the gears requires a lot of data about how you want the gearbox to operate, what maximum torque and speeds are required, what materials you want to use, etc.

What kind of gears and what ratios , axes locations , center-distances , application , load types , mounting positions - need a host of details to calculate gear prportions , buddy.

I think some thing is wrong with your arrangement and calculation. In Gearboxes, output power is usually in the range of 0.85 to 0.99 % of the Input, because of friction losses. your Input power is about 182.7 Kw and the output power is 101.5 Kw. In other words speed ratio is about 2.98 but torque ratio is about 0.6 (instead of being equal to ~0.33)!!!

Please give some more information about your problem.

Where from you generated these figures? OP didn't give it.

He calculated from torque and rpm.

You may be interested:

Machine Design magazine

(website: http://machinedesign.com/?p=1)

In the Feb 2012 edition there is an article (p 56 in the hard copy) on designing gearboxes for efficiency.