powerbank-bike-clamp.scad

   1 // -*- C -*-
   2
   3 include <utils.scad>
   4
   5 tube_dia = 22.4;
   6
   7 hinge_around = 2.5;
   8 hinge_pin = 1.8 + 0.75;
   9 main_th = 3;
  10 minor_wall_min = 1;
  11
  12 screw = 5.0 + 0.75;
  13 screw_head = 8.7 + 1.2;
  14 screw_nut_across = 7.9 + 0.75;
  15 screw_nut_th = 3.9 + 0.75;
  16 screw_head_h = 3.6 + 0.75;
  17
  18 knob_behind_across = 12.2 + 0.75;
  19 behind_knob_th = 5;
  20
  21 clamp_width = 20;
  22
  23 clamp_gap = 2;
  24
  25 lower_th = 1;
  26
  27 overlap_l = 0.1;
  28
  29 bridge_slop = 1.2;
  30
  31 hinge_lobes = 2;
  32 hinge_gap_z = 0.75;
  33 hinge_gap_xy = 0.75;
  34
  35 $fs = 0.1;
  36 $fa = 5;
  37
  38 bank_eps_bbox_x = [149, 598];
  39 bank_eps_bbox_y = [274, 1452];
  40
  41 bank_y_sz = 102.25 + 0.50;
  42 bank_x_sz = (24.9 + 0.5);
  43 bank_recess_y = 5;
  44
  45 strap_th = 3;
  46 strap_above = 2.5;
  47
  48 // calculated
  49
  50 bank_recess_dx = minor_wall_min;
  51
  52 pspt_to_mm = 25.4 / 72;
  53
  54 hinge_stride = (clamp_width + hinge_gap_z) / hinge_lobes;
  55
  56 main_r = tube_dia/2 + main_th;
  57
  58 hinge_outer_r = hinge_around + hinge_pin/2;
  59 hinge_y = tube_dia/2 + hinge_outer_r;
  60
  61 screw_max_y_lhs = -main_r -screw_nut_across/2;
  62 screw_max_y_rhs = -main_r -knob_behind_across/2;
  63
  64 screw_y = min(screw_max_y_lhs,
  65               screw_max_y_rhs);
  66
  67 bot_y = screw_y -max( screw_nut_across, knob_behind_across/2 )
  68   -minor_wall_min;
  69
  70 holder_x_sz = bank_x_sz + bank_recess_dx*2;
  71 bank_bot_y = strap_above + strap_th;
  72 strap_r = strap_th;
  73
  74 echo(bot_y);
  75
  76 module TubePlan(){ circle(r = tube_dia/2); }
  77 module HingePinPlan(){ translate([0, hinge_y]) circle(r= hinge_pin/2); }
  78 module HingeBodyPlan(){ translate([0, hinge_y]) circle(r= hinge_outer_r); }
  79
  80 module TubeClampLeftPlan(){
  81   difference(){
  82     union(){
  83       polygon([[ 0,                    hinge_y + hinge_outer_r ],
  84                [ -main_r + overlap_l,  hinge_y + hinge_outer_r ],
  85                [ -main_r + overlap_l,  bot_y                   ],
  86                [ -clamp_gap/2,         bot_y                   ],
  87                [ -clamp_gap/2,         0,                      ],
  88                [ 0,                    0,                      ],
  89                ]);
  90       HingeBodyPlan();
  91     }
  92     TubePlan();
  93     HingePinPlan();
  94   }
  95 }
  96
  97 module TubeClampLeft() { ////toplevel
  98   linextr(-clamp_width/2, clamp_width/2)
  99     TubeClampLeftPlan();
 100 }
 101
 102 module TubeClampRightPlan(){
 103   difference(){
 104     union(){
 105       rectfromto([ clamp_gap/2,                   bot_y ],
 106                  [ clamp_gap/2 + behind_knob_th,  0     ]);
 107       intersection(){
 108         circle(r= main_r);
 109         union(){
 110           rectfromto([0,0],
 111                       main_r *  [5,5]);
 112           rectfromto([ clamp_gap/2, main_r*5 ],
 113                       main_r * [2,-5]);
 114         }
 115       }
 116       HingeBodyPlan();
 117     }
 118     TubePlan();
 119     HingePinPlan();
 120   }
 121 }
 122
 123 module SomeClamp(hinge_alt=false){
 124   difference(){
 125     linextr(-clamp_width/2, clamp_width/2)
 126       children(0);
 127
 128     linextr_x_yz(-main_r*5, main_r*5)
 129       translate([screw_y, 0])
 130       circle(r= screw/2);
 131
 132     for (i=[0 : hinge_lobes-1]) {
 133       translate([0,
 134                  hinge_y,
 135                  -clamp_width/2 + i * hinge_stride
 136                  + (hinge_alt ? hinge_stride/2 : 0)
 137                  ])
 138         linextr(-hinge_gap_z, hinge_stride/2)
 139         square(hinge_outer_r*2 + hinge_gap_xy, center=true);
 140     }
 141   }
 142 }
 143
 144 module PowerBankItselfSidePlan(){
 145   translate([0, bank_bot_y])
 146     scale( bank_x_sz / ( (
 147                           bank_eps_bbox_x[1] -
 148                           bank_eps_bbox_x[0]
 149                           ) * pspt_to_mm ))
 150     translate(pspt_to_mm *
 151               [-0.5 * (bank_eps_bbox_x[0] +
 152                        bank_eps_bbox_x[1]),
 153                -bank_eps_bbox_y[0]])
 154     import("powerbank-anker-10000.dxf", convexity=5);
 155 }
 156
 157 module PowerBankItself(){ ////toplevel
 158   rotate([0,90,0])
 159     linextr_y_xz(-bank_y_sz/2,
 160                  +bank_y_sz/2)
 161     PowerBankItselfSidePlan();
 162 }
 163
 164 module PowerBankSidePlan(){ ////toplevel
 165   render() difference(){
 166     rectfromto([ -holder_x_sz/2,  0 ],
 167                [ +holder_x_sz/2,  bank_recess_y + bank_bot_y ]);
 168
 169     PowerBankItselfSidePlan();
 170   }
 171 }
 172
 173 module PowerBankStrapCut(){ ////toplevel
 174   difference(){
 175     rectfromto([ -holder_x_sz, -0.05 ],
 176                [ +holder_x_sz, strap_th + strap_r ]);
 177     hull(){
 178       for (sx=[-1,+1]) {
 179         translate([sx * (holder_x_sz/2 - strap_r + 0.1),
 180                    strap_th + strap_r])
 181           circle(strap_r);
 182       }
 183     }
 184   }
 185 }
 186
 187 module PowerBankHolderTest(){ ////toplevel
 188   difference(){
 189     linextr(-20,20) PowerBankSidePlan();
 190     linextr(0, strap_th) PowerBankStrapCut();
 191   }
 192 }
 193
 194 module TubeClampLeft() { ////toplevel
 195   // We want this to print with the recess overhand to the right
 196   // where the workpiece cooling fan is
 197   rotate([0,0,180]){
 198     difference(){
 199       SomeClamp(true)
 200         TubeClampLeftPlan();
 201
 202       translate([0, screw_y, 0]) {
 203         linextr_x_yz(-(clamp_gap/2 + screw_nut_th), 0)
 204           square([screw_nut_across,
 205                   screw_nut_across / cos(30) + bridge_slop*2],
 206                  center=true);
 207
 208         linextr_x_yz(-main_r, -main_r + screw_head_h)
 209           square([screw_head, screw_head + bridge_slop*2],
 210                  center=true);
 211       }
 212     }
 213   }
 214 }
 215
 216 module TubeClampRight() { ////toplevel
 217   rotate([0,0,180])
 218     rotate([180,0,0])
 219     SomeClamp()
 220     TubeClampRightPlan();
 221 }
 222
 223 module TubeClampDemo() { ////toplevel
 224   TubeClampLeft();
 225   rotate([180,0,0])
 226     TubeClampRight();
 227 }