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 what is centrifugal force and velocity ratios in gears Post Reply Forum
 Posted by: bobthedog ® 04/13/2007, 09:29:26 Author Profile eMail author Edit What is centrifugal force relating to shafts? Ok one big has 15 teeth the other has 30 teeth so the velocity ratio is 2 is this correct and how come the velocity ratio is 2? If a gear had 40 teeth and the other 12 what would the velocity ratio be there and how is that worked out. The minimum teeth in a pinion is 19 and the maximum teeth in a wheel is 150 this gives a velocity ratio of the order 8:1 how is this ? How is this worked out? Teeth in a pinion is 25 and the teeth in a wheel is 92 what is the velocity ratio order here. What is the difference between velocity ratio order and velocity ratio? Thanks for help DONT GIVE UP THE FAITH

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 Re: what is centrifugal force and velocity ratios in gears Re: what is centrifugal force and velocity ratios in gears -- bobthedog Post Reply Top of thread Forum
 Posted by: materialboy ® 04/13/2007, 18:43:09 Author Profile eMail author Edit one big has 15 teeth the other has 30 teeth so the velocity ratio is 2 is this correct and how come the velocity ratio is 2.V= distance/time V(30-teeth) = 2*pi*r1/T (r1 = radius (15) + tip of gear) V(15-teeth) = 2*pi*r2/T (r2 = radius (7.5) + tip of gear)if they are connected via same chain, than for 15 teeth to coover up the same distance as 30 teeth. (i.e. 15 teeth gear (pinion) has to rotate twice to match up with the rotation of 30 teeth). Hence gear ratio is said to be 2:1 which is another term is 2 times the velocity of 15 teeth = 1 times the rotation of 30 teeth . (connected via chain/belt)The minimum teeth in a pinion is 19 and the maximum teeth in a wheel is 150 this gives a velocity ratio of the order 8:1 how is this ? How is this worked out? How far I have knowledge of gears - Gears are always made in multiple of pinion gear. So for a Pinion of 19 max teeth will (19*8=152 teeth) to give velocuty tario of 8:1

 tip of gear and 8:1 Re: Re: what is centrifugal force and velocity ratios in gears -- materialboy Post Reply Top of thread Forum
 Posted by: bobthedog ® 04/14/2007, 09:10:39 Author Profile eMail author Edit What is the tip of the gear and how does 8;1 give 152 teeth that is the number of teeth isnt it not the acutal v ratio??? Also in circular functions what is sine cosine tan co tangent Thanks DONT GIVE UP THE FAITH

 Re: tip of gear and 8:1 Re: tip of gear and 8:1 -- bobthedog Post Reply Top of thread Forum
 Posted by: materialboy ® 04/14/2007, 14:51:01 Author Profile eMail author Edit Tip of the gear is the top end of gear8:1 is the gear ratio as described.acutal v ratio :- Is ur question on gear ratio or N/V ratio. where N means for sensing the engine speed V means for sensing the vehicle speed To my knowledge N/V ratio are used to determine gear position and not gear ratio.

 Re: Re: tip of gear and 8:1 Re: Re: tip of gear and 8:1 -- materialboy Post Reply Top of thread Forum
 Posted by: bobthedog ® 04/16/2007, 08:30:16 Author Profile eMail author Edit Ok so 8:1 is the actual ratio but what am trying to find out is why times it by 8 to get 152. Confused Its got nothing to do with N sensing the engine speed and V sensing the vehicle speed. If one pinion has 14 teeth and the other wheel has like 78 teeth what is the velocity ratio here and how is it worked out thanks. DONT GIVE UP THE FAITH

 Re: Re: Re: tip of gear and 8:1 Re: Re: Re: tip of gear and 8:1 -- bobthedog Post Reply Top of thread Forum
 Posted by: materialboy ® 04/16/2007, 11:55:35 Author Profile eMail author Edit Mate you really need to study on gearsPinion = 19 teeth then drve gear = 19(x)8 = 152 teeththis is how u get 8:1 ratio.Velocity ratio depends upon what rate u want the RPM of your turbine blades and wut rate can ur engine Provide Example if engine runs at 2000 rpm at max And u want the blade run at 1000 rpm than u need to set 2:1 gear to get the blade run at that speed.On ques -2, i really do not know how u got 78 teeth. Hope it helps

 finally got it Re: Re: Re: Re: tip of gear and 8:1 -- materialboy Post Reply Top of thread Forum
 Posted by: bobthedog ® 04/17/2007, 07:37:06 Author Profile eMail author Edit Ok got it now thanks. DONT GIVE UP THE FAITH