gear transmission ratio

[mozzaaa7]

Good evening,

I have a problem with the sizing of an electric motor, especially the final transmission ratio between it and the wheels. below in the attached file "cartel1.pdf" are the engine data. the same will be mounted directly to a reducer that will transmit the bike to the wheels. the rear traction car has a mass of 1300 kg ca with wheel diameter = 610 mm.
two engines of 5 kw each and the car will have to be able to reach a speed of 85 km/h on the floor and exceed a slope of 22%.
the pair will then be doubled but the engines will have the same sync speed.
My doubts are:

how do I find the couple necessary to overcome this slope?
What is the transmission ratio from the motor to the wheels?

I would also like to comment on the correct reading of the table which I have attached and the values contained in it, not all of us are clear.

thanks in advance

 

[exxon]

how do I find the couple necessary to overcome this slope?

No physical memory 1?

with regard to the tables, apart from some columns with obvious meaning, for others it should be asked who made them.

 

[meccanicamg]

Let's proceed by degrees.
the columns indicate:
- angle speed in rpm
- couple in nm
- power made to the motor shaft in kw
- motor voltage in v
- current absorbed by the motor in a
- battery power in kw
- performance between battery power and output power
- s2 and s3 could refer to the non-continuous cycle, therefore different from s1
- battery voltage in v
- battery current in a
- power frequency in hz
- % of the engine and its flow
- saturation frequency in hz
- thighs that is the displacement between active and reactive current
- turns and pair

As far as the calculation is concerned, you need to read the transport cart posts or similar things we treated a few months ago.

the slope is nothing but the sloping position of the weight and strength that dissipates power for friction and because of the aerodynamics not perfect.

If you have enough torque for your vehicle it is not said that you need a gearbox.
you have to bend the engine (pair/turns and power/turns) and determine your load where it is. If you're in and under the curve okay, otherwise we're not there.

 

[meccanicamg]

made very quickly the account you have two engines from 5kw to about 2200rpm and with i=3 reduction ratio.

However the table has the values sorted by chance and not by rpm...so it is rewritten to give a sense.

 

[mozzaaa7]

As for the couple to overcome the slope I did, I actually did not have the value of acceleration but I managed to find it.

on the table I have doubts fundamentally only on those values of s2 and s3. I also ordered the values of the same to make it clearer to read.

Can you tell me the calculations you made to calculate that reduction ratio?

 

[meccanicamg]

set a reasoning. we have already faced it in other posts. then we discuss it.

 

[mozzaaa7]

I set an excel sheet to set only the data and have everything automatically. design data are:
mass: 1300kg
initial speed: 0 km/h
final speed: 85 km/h
Time: 22
wheel radius: 305 mm
slope: 22%

from which I echo:
speed: 23.6 m/s
acceleration: 1.1 m/s^2
wheel circumference: 1916,4 mm

echo the force agent on the wheel:
== sync, corrected by elderman ==
from which the couple:
c = f*r_ruota = 425.5 nm

strength and couple needed to win the slope of 22% embroidery by multiplying the strength found for sen22 and I get 305.5 n with a pair of 93.2 nm.

I'm sure I'm wrong. the transmission report now, how do I find it?

 

[exxon]

right to start: sen22 what is it? I hope not sen (22°). .

 

[mozzaaa7]

22% of slope would be, 22m of altitude difference route on 100m of road travelled. the angle formed by the hypothetical triangle is about 13,5°, or 0.218

 

[exxon]

just to continue: asin(0.22)= 12.7°, not 13.5°...

 

[+forte]

cosfi is the active power ratio apparent power
with calc sen-1 and find the corner

 

[mozzaaa7]

All right, everybody, thank you.
the rest of the calculations you tell me?

 

[Lettore espatriato]

Where does that wheel size come from? I imagine it will be a standard tyre.

 

[exxon]

@+forteI just wrote a post in which I openly invite you not to write more things about which you have not enough knowledge and, by chance, I open this thread and read your post

cosfi is the active power ratio apparent power
with calc sen-1 and find the corner

The operation is cos-1, not sin-1!

There's no single post where you don't write nonsense. You need to set yourself up.

 

[+forte]

@+forteI just wrote a post in which I openly invite you not to write more things about which you have not enough knowledge and, by chance, I open this thread and read your post


The operation is cos-1, not sin-1!

There's no single post where you don't write nonsense. You need to set yourself up.

cosfi is the active power ratio apparent power < reported to post 3 of mechanicalmg
with calc sen-1 and find the angle < referred to post 9 of mozzaaa7

 

[+forte]

@+forteThere's no single post where you don't write nonsense. You need to set yourself up.

change tono please I am always kind darling

 

[+forte]

@+forteI just wrote a post in which I openly invite you not to write more things about which you have not enough knowledge and, by chance, I open this thread and read your post


The operation is cos-1, not sin-1!

There's no single post where you don't write nonsense. You need to set yourself up.

Don't forget to read this.https://www.cad3d.it/forum1/threads/planarità-parallelismo.54973/post-428156