Need advice on creating planetary gear
- Thread starter Kunstmaan
- Start date
albie0803
Alibre Super User
Thanks for that Miles. That explains why odd ratios occur, its creating a gearset close to the ratio you want but with the correct tooth sum to equispace the planetary gears. I have also looked up calculating planetary ratios and understand it a bit better now. Even if we can't actually help Berdien, I have still learnt something.
Last edited:
Oldbelt
Alibre Super User
Albie thank you for our discussion, your conclusion about helping Berdien with a 1:21 with sun gear 23 can maybe be made
I have struggled with it in several hours,
Miles said in another way, my sentence about division by 3.
He inform that this division factor is depending at how, many planets there is in the Gear. Thank you for that Miles.
Burdiens gear, can after what we have learned, be made with one planet gear in first stage 1:7 fixed ring gear.
second stage 1:3. with a bigger module to get a ring gear dia. near the first stage.
I have struggled with it in several hours,
Miles said in another way, my sentence about division by 3.
He inform that this division factor is depending at how, many planets there is in the Gear. Thank you for that Miles.
Burdiens gear, can after what we have learned, be made with one planet gear in first stage 1:7 fixed ring gear.
second stage 1:3. with a bigger module to get a ring gear dia. near the first stage.
Oldbelt
Alibre Super User
Stage 1 i = 1:7; sun1 Z=23; ring1 Z= 138 ring Fixed; i = 1+ 138/23 = 7; sum rule : Zsun + Zring / x shall give an integer 23+138 = 161 there is now divisor apart from x =1 fulfilling
that means a 1:7 gear can be made with one planetary gear wheel. Modul is 0.75 the nearest Z planet is 58, this wheel shall have an addendum.
Stage 2 i= 1:3 sun2 Z=18; ring2 Z=36 ring fixed; i= 1 +36/ 18 = 3 ; sum rule : Zsun + Zring / x shall give an integer 18+36 = 54 / x x =3 fulfilling the rule 3 planetary gear can be used.
Modul 3 is used given a ring gear size almost similar to ring gear 1
GIOV
Alibre Super User
This topic is not my field but I suggest ask firth what king of 8mm motor is, What is the RPM and the Torque & Power that need to achieve .So the flow diagram must be clear before go to particular mechanical design detail.
Example:
Example:
Kunstmaan
Alibre Super User
where can I find this scriptI've chosen 0.75M as the sun gear works out close to the 18mm given earlier.
Oldbelt
Alibre Super User
Kunstmaan.
Have you open my package file and loaded the gear. ?
The green sun gear is the input and the red planetary carrier is the output .
The model is ready the two ring gears is locked (fixed) , there is no need to "playing around" with the model.
There is no animation in Alibre.
You test the function moving the green sun, there are a hole, click at it with left mouse button and rotate around the centre.
It easiest to do if the assembly is rotated so the green sun is in front of the display.
The "script" is a SW and not a script connected to Alibre as far as can see, and it maybe haven't the sum rule.
Giov's post have no relation to what we discus in this thread.
Have you open my package file and loaded the gear. ?
The green sun gear is the input and the red planetary carrier is the output .
The model is ready the two ring gears is locked (fixed) , there is no need to "playing around" with the model.
There is no animation in Alibre.
You test the function moving the green sun, there are a hole, click at it with left mouse button and rotate around the centre.
It easiest to do if the assembly is rotated so the green sun is in front of the display.
The "script" is a SW and not a script connected to Alibre as far as can see, and it maybe haven't the sum rule.
Giov's post have no relation to what we discus in this thread.
GIOV
Alibre Super User
Ok Oldbelt.
PD. Do not forguet the inertia factor that make the gear without vibrations..so the gear connected to the red ring gear and the green sun gear may need a brother one.
Oldbelt
Alibre Super User
Giov , The red output carrier with planetary wheels is in dynamically balance, the carrier for first stage need a counter balance.
My proposal is not a design to produce, its only a demonstration of a 1: 21 gear,
I have a assembly with ball bearings and of course wheels with teeth.
But Kunstmaan need to inform about the revolution speed and needed moment before a design can be finished.
Material for manufacturing , method , 3D print etc.
My proposal is not a design to produce, its only a demonstration of a 1: 21 gear,
I have a assembly with ball bearings and of course wheels with teeth.
But Kunstmaan need to inform about the revolution speed and needed moment before a design can be finished.
Material for manufacturing , method , 3D print etc.
Kunstmaan
Alibre Super User
Hi all,
Just downloaded the second example.
Maybe its time/better to drop the 23T pinion and use a better one.
If the gears can be obtained from stock would be nice, otherwise 3D printing schal be the option.
The OD for the ring-gear would be 90mm max. and the motor used wil be the XD3420 wiht a 8mm axle diameter.
What more info do you guts need, let me know.
Berdien
GIOV
Alibre Super User
Regarding to the Electric Motor XD3420 I find this spec in the web:
Kunstmaan
Alibre Super User
Thats information I allready have
Oldbelt
Alibre Super User
Berdien
#1 If you drop the wanted i= 1:21 then it is possible to get the the outer dia. at the gear housing below 90mm. OK ??
#2 Witch of those possibilities do you prefer ?? 1:18; 1:20; 1:24. The pinion(Sun) Z =23 is dropped, Z will be calculated as a function of the ring gear Z.
#3 How fast will the input axel rotate rev/min ??
#4 What device, component is driven of the output axel??
#5 How big is the torque at the out axel??
#6 Will there be a big wear out so ball bearings is needed, meaning continuously drift or intermittent??
#7 How will you fabricate the parts??
#1 If you drop the wanted i= 1:21 then it is possible to get the the outer dia. at the gear housing below 90mm. OK ??
#2 Witch of those possibilities do you prefer ?? 1:18; 1:20; 1:24. The pinion(Sun) Z =23 is dropped, Z will be calculated as a function of the ring gear Z.
#3 How fast will the input axel rotate rev/min ??
#4 What device, component is driven of the output axel??
#5 How big is the torque at the out axel??
#6 Will there be a big wear out so ball bearings is needed, meaning continuously drift or intermittent??
#7 How will you fabricate the parts??
Kunstmaan
Alibre Super User
#1 OK, I have to make a new 3D printed housing so smaller is no problem
#2 1:18 to 1:42 maybe in two stages
#3 Between 100 and 800 rpm (PWM controlled)
#4 A 20mm(diam) steel axle that drives a wirewound resistor bank
#5 they think that the load wil be 5Kg max
#6 intermittent, I whas thinking about 624zz bearings
#7 If the sun and planet gears kan be obtained from a supplier would be nice, otherwise 3D printed (need then advice on best to used material)
I hope you got enough information.
Source for gears: https://www.hpcgears.com/
Gearboxes:
www.c-var.com
Gearboxes:
Varitron - Planetary Precision Gearbox for Servo Motor
Varitron low backlash planetary Precision gearbox promise dynamic performances, backlash and torsional stiffness for motion control
www.c-var.com
Oldbelt
Alibre Super User
Reduction 1:24 can be made with the gear wheel from the "Miles" company in two steps. 1:6 in serie 1:4 .
Step #1 Ring Gear GPSO.5-120 GPA
sun Gear GO.5-24 PG
Planet Gear 3 piece's GO.5-48PG
Step #2 Ring Gear GPSO.5-120 GPA
sun Gear GO.5-40 PG
Planet Gear 4 piece's GO.5-40 PG
The ring gear DO is 70mm and 8mm in width
All other gear is 5mm in with.
Step #1 Ring Gear GPSO.5-120 GPA
sun Gear GO.5-24 PG
Planet Gear 3 piece's GO.5-48PG
Step #2 Ring Gear GPSO.5-120 GPA
sun Gear GO.5-40 PG
Planet Gear 4 piece's GO.5-40 PG
The ring gear DO is 70mm and 8mm in width
All other gear is 5mm in with.
GIOV
Alibre Super User
Hi Oldbelt,
May be you find some data in this good Japan resource:
May be you find some data in this good Japan resource: