Source code for boxes.generators.planetary

#!/usr/bin/env python3
# Copyright (C) 2013-2016 Florian Festi
#
#   This program is free software: you can redistribute it and/or modify
#   it under the terms of the GNU General Public License as published by
#   the Free Software Foundation, either version 3 of the License, or
#   (at your option) any later version.
#
#   This program is distributed in the hope that it will be useful,
#   but WITHOUT ANY WARRANTY; without even the implied warranty of
#   MERCHANTABILITY or FITNESS FOR A PARTICULAR PURPOSE.  See the
#   GNU General Public License for more details.
#
#   You should have received a copy of the GNU General Public License
#   along with this program.  If not, see <http://www.gnu.org/licenses/>.

from boxes import *
import math


[docs]class Planetary(Boxes): """Planetary Gear with possibly multiple identical stages""" ui_group = "Part" def __init__(self): Boxes.__init__(self) self.argparser.add_argument( "--sunteeth", action="store", type=int, default=8, help="number of teeth on sun gear") self.argparser.add_argument( "--planetteeth", action="store", type=int, default=20, help="number of teeth on planets") self.argparser.add_argument( "--maxplanets", action="store", type=int, default=0, help="limit the number of planets (0 for as much as fit)") self.argparser.add_argument( "--deltateeth", action="store", type=int, default=0, help="enable secondary ring with given delta to the ring gear") self.argparser.add_argument( "--modulus", action="store", type=float, default=3, help="modulus of the theeth in mm") self.argparser.add_argument( "--shaft", action="store", type=float, default=6., help="diameter of the shaft") # self.argparser.add_argument( # "--stages", action="store", type=int, default=4, # help="number of stages in the gear reduction") def render(self): ringteeth = self.sunteeth + 2 * self.planetteeth spoke_width = 3 * self.shaft pitch1, size1, xxx = self.gears.sizes(teeth=self.sunteeth, dimension=self.modulus) pitch2, size2, xxx = self.gears.sizes(teeth=self.planetteeth, dimension=self.modulus) pitch3, size3, xxx = self.gears.sizes( teeth=ringteeth, internal_ring=True, spoke_width=spoke_width, dimension=self.modulus) t = self.thickness planets = int(math.pi / (math.asin(float(self.planetteeth + 2) / (self.planetteeth + self.sunteeth)))) if self.maxplanets: planets = min(self.maxplanets, planets) # Make sure the teeth mash ta = self.sunteeth + ringteeth # There are sunteeth+ringteeth mashing positions for the planets if ta % planets: planetpositions = [round(i * ta / planets) * 360 / ta for i in range(planets)] else: planetpositions = planets # XXX make configurable? profile_shift = 20 pressure_angle = 20 self.parts.disc(size3, callback=lambda: self.hole(0, 0, self.shaft / 2), move="up") self.gears(teeth=ringteeth, dimension=self.modulus, angle=pressure_angle, internal_ring=True, spoke_width=spoke_width, mount_hole=self.shaft, profile_shift=profile_shift, move="up") self.gears.gearCarrier(pitch1 + pitch2, spoke_width, planetpositions, 2 * spoke_width, self.shaft / 2, move="up") self.gears(teeth=self.sunteeth, dimension=self.modulus, angle=pressure_angle, mount_hole=self.shaft, profile_shift=profile_shift, move="up") numplanets = planets if self.deltateeth: numplanets += planets deltamodulus = self.modulus * ringteeth / (ringteeth - self.deltateeth) self.gears(teeth=ringteeth - self.deltateeth, dimension=deltamodulus, angle=pressure_angle, internal_ring=True, spoke_width=spoke_width, mount_hole=self.shaft, profile_shift=profile_shift, move="up") for i in range(numplanets): self.gears(teeth=self.planetteeth, dimension=self.modulus, angle=pressure_angle, mount_hole=self.shaft, profile_shift=profile_shift, move="up")