ball/flying valve gear motor

[meccanicamg]

I looked at the formulas of niemann for the theoretical game jt and for the normal game jn, which are calculated through the tolerances indicated by the table of mechanicsmg, but knowing jt or jn how is the tolerance to be assigned to the wildaber measure? I looked at a couple of drawings and noticed that jn is double the tolerance assigned to the wildaber measure (or discard), is it a coincidence?

I never deepened but I think it's a coincidence because the wildhaber is read on two....tre....4...5....11 teeth depending on m and z. you should deepen on the niemann if there is something written or on the pietro book.

 

[meccanicamg]

I did a test with the khk program, hypothesized two toothed wheels, in the first test I kept the theoretical data, in the example I considered two wheels module 1 z 50.
In the second test, on a wheel I made a correction of x= -013, in practice, to give game to the teeth, with the creator you enter more than the theorist. I'll attach the two sheets to you, so you realize the variations on the control quotas.

by moving profile you do not create and do not remove the game but change the primitive diameter of actual rolling.
the game changes it with the game jn parameter.

 

[Mattymecc]

but jn does not depend on the tolerances of the table you indicated?

 

[meccanicamg]

but jn does not depend on the tolerances of the table you indicated?

each class of tolerance of the gear is subject to all measures its tolerances.
It is also true that it is possible to the practical side to have more game or less game for specific needs and maintain tolerances on the rest.

 

[PIETRO2002]

by moving profile you do not create and do not remove the game but change the primitive diameter of actual rolling.
the game changes it with the game jn parameter.

practically to give the game on a gear, which I know, there are two ways:

you enter with the creator radially as mentioned above, practically making a sort of negative correction.

entering with the creator at theoretical altitude and then making an axial shift of the creator (shifting ).

both methods make the tooth thickness decrease so as to create the required game.

If you know any other method, let me know, I'm curious.

 

[PIETRO2002]

thank you again for the clarifications, but I think not to be explained: with the tables of mechanicsmg I find the tolerance of tooth thickness and that on the whole, then calculate the game with the formulas of niemann. but on the "cartellino" of the measures of the toothed wheel, what tolerance do I put for the measure of discard?
The scheme you made me is the relationship between normal and transversal play?

the scheme I posted you serves to see how radially enter with the creator compared to the theoretical primitive diameter to get the normal game required.

 

[Mattymecc]

thanks to both for the clarifications, I will deepen this aspect of the dense wheels, very important in the production and design.. .

 

[PIETRO2002]

thank you again for the clarifications, but I think not to be explained: with the tables of mechanicsmg I find the tolerance of tooth thickness and that on the whole, then calculate the game with the formulas of niemann. but on the "cartellino" of the measures of the toothed wheel, what tolerance do I put for the measure of discard?
The scheme you made me is the relationship between normal and transversal play?

Working in series gears, the tolerance is placed on the theoretical primitive diameter, for control is used a "ingranometer" equipment with a sample wheel that ingrates precisely with the gear to be controlled, it turns the torque of toothed wheels and you can see the total error composed. otherwise the methods are to measure with the micrometer to plate the rope quota on a tot. number of teeth or to make control by interposing in the teeth of the calibrated rollers.

 

[meccanicamg]

practically to give the game on a gear, which I know, there are two ways:

you enter with the creator radially as mentioned above, practically making a sort of negative correction.

entering with the creator at theoretical altitude and then making an axial shift of the creator (shifting ).

both methods make the tooth thickness decrease so as to create the required game.

If you know any other method, let me know, I'm curious.

I think it is only shifting the method to create game on the toothing because it is a translation of the tool that removes material to the profile in a "parallele" way to the original profile.
make a negative correction changes the operating diameter and I think it affects much more negatively on performance precisely because it does not follow the geometric aspects of ingration.
should be tried to evaluate with kisssoft that is the only complete and reliable program to make gears studied so in detail.

niemann also points out that at the same quality of gear it is possible to have a different game depending on the mechanical application.

I would be interested to know what the first volume of henriot says... but I miss pages from 65 to 96, where it also speaks of tolerance on wildhaber.

 

[Mattymecc]

Thanks again to both of you, I'd need those pages of the henriot...

 

[PIETRO2002]

I try to make a distinction between different types, for clarity:
type to
type b
type

type a : poor precision gears, large volumes, cemented.
the processing cycle:
turning
teething
cementation + tempering + extension
In this case, it's convenient to get the detachment game with a single pass of creator by sinking more so as to get some sort of negative correction.
In this case it must also be taken into account, that after cementation, following the change of the crystalline lattice, the material "flames".

type b: "normal" precision gears not treated.
the processing cycle:
turning
teething
In this case the detachment is done with a stretching pass and then to get the required game, two axial movements of the creator (shifting) are made to widen the two tooth compartments symmetrically.

type c: precise gears, heat treated ( cemented or hardened)
the processing cycle:
turning
teething
heat treatment
grinding of teeth
In this case the toothing operation must leave the overmetal on the sides of the teeth which will later be removed from the grinding, so the game will be given precisely by this last operation.

My description is macroscopic, there may be other cases according to the types of pieces, comments and punctuations are good if what I wrote contains errors!

 

[PIETRO2002]

I attach a pdf concerning the tolerances of the teeth.

 

[meccanicamg]

I try to make a distinction between different types, for clarity:
type to
type b
type

type a : poor precision gears, large volumes, cemented.
the processing cycle:
turning
teething
cementation + tempering + extension
In this case, it's convenient to get the detachment game with a single pass of creator by sinking more so as to get some sort of negative correction.
In this case it must also be taken into account, that after cementation, following the change of the crystalline lattice, the material "flames".

type b: "normal" precision gears not treated.
the processing cycle:
turning
teething
In this case the detachment is done with a stretching pass and then to get the required game, two axial movements of the creator (shifting) are made to widen the two tooth compartments symmetrically.

type c: precise gears, heat treated ( cemented or hardened)
the processing cycle:
turning
teething
heat treatment
grinding of teeth
In this case the toothing operation must leave the overmetal on the sides of the teeth which will later be removed from the grinding, so the game will be given precisely by this last operation.

My description is macroscopic, there may be other cases according to the types of pieces, comments and punctuations are good if what I wrote contains errors!

in the personal experience there are only so much type c and little type b. absent type a. therefore I have no experience on large batches but on single products, in natural state, hardened, cemented and nitrated (a little less).

 

[PIETRO2002]

in the personal experience there are only so much type c and little type b. absent type a. therefore I have no experience on large batches but on single products, in natural state, hardened, cemented and nitrated (a little less).

we have to put together, I have lived a lot with the types to

 

[meccanicamg]

I fully agree, in fact we integrate a lot on the subject, each for their own experience. Is this the beauty?

 

[PIETRO2002]

an interesting site for calculating the values of the teeth tolerances is:

mechanicalcheck.com

 

[Enrico Povolo]

hello to all, I'm proceeding but with great caution.

These days we have entered the material section, they propose:
1- fc-0205ht (hrc: 36 , uts: 690mpa , yts: 690 mpa ) previously used
2- fn-0208ht (hrc: 32 , uts: 930mpa , yts: 930 mpa )
3- fln2c-4005ht ( hrc: 31 , uts: 1160 mpa , yts: 980 mpa )
4 fc-0205ht (hrc: 34 , uts: 895 mpa, yts: 895 mpa )
all density 7g/cm3.. .
(other references can be found in the table "mpif standard 35" )

I would like to understand: is it better to prefer traction properties to hardness?

using the khk calculator asks me the parameters in photo.
σb is equivalent to uts and yts?
I would like to find a similar material for further verification. . .

 

[PIETRO2002]

hello to all, I'm proceeding but with great caution.

These days we have entered the material section, they propose:
1- fc-0205ht (hrc: 36 , uts: 690mpa , yts: 690 mpa ) previously used
2- fn-0208ht (hrc: 32 , uts: 930mpa , yts: 930 mpa )
3- fln2c-4005ht ( hrc: 31 , uts: 1160 mpa , yts: 980 mpa )
4 fc-0205ht (hrc: 34 , uts: 895 mpa, yts: 895 mpa )
all density 7g/cm3.. .
(other references can be found in the table "mpif standard 35" )

I would like to understand: is it better to prefer traction properties to hardness?

using the khk calculator asks me the parameters in photo.
σb is equivalent to uts and yts?
View attachment 60426I would like to find a similar material for further verification. . .

I have no experience sintered gears, but from the table of khk you have to consider a material type c45 untreated. I don't know if you can confronate with your material, densities are different!

 

[PIETRO2002]

Are you considering the details missing from the 3d models you posted?

type:

bushings or bearings.

hammerheads.

method of locking the sun on the satellite carrier.

axial seal of the hammer holders.

axial seal of satellites on its pin.

method of blocking the satellite pins on the satellite carrier.

centring method between the various stages.

 

[meccanicamg]

hello to all, I'm proceeding but with great caution.

These days we have entered the material section, they propose:
1- fc-0205ht (hrc: 36 , uts: 690mpa , yts: 690 mpa ) previously used
2- fn-0208ht (hrc: 32 , uts: 930mpa , yts: 930 mpa )
3- fln2c-4005ht ( hrc: 31 , uts: 1160 mpa , yts: 980 mpa )
4 fc-0205ht (hrc: 34 , uts: 895 mpa, yts: 895 mpa )
all density 7g/cm3.. .
(other references can be found in the table "mpif standard 35" )

I would like to understand: is it better to prefer traction properties to hardness?

using the khk calculator asks me the parameters in photo.
σb is equivalent to uts and yts?
View attachment 60426I would like to find a similar material for further verification. . .

These parameters are not indicated in your material.....so it is difficult to deal specifically.