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
  17 knob_behind_across = 12.2 + 0.75;
  18 behind_knob_th = 5;
  19
  20 clamp_width = 20;
  21
  22 clamp_gap = 2;
  23
  24 lower_th = 1;
  25
  26 overlap_l = 0.1;
  27
  28 bridge_slop = 1.2;
  29
  30 hinge_lobes = 2;
  31 hinge_gap_z = 0.75;
  32 hinge_gap_xy = 0.75;
  33
  34 $fs = 0.1;
  35 $fa = 5;
  36
  37 bank_eps_bbox_x = [149, 598];
  38 bank_eps_bbox_y = [274, 1452];
  39
  40 bank_y_sz = 102.25 + 0.50;
  41 bank_x_sz = (26.0 + 0.5);
  42 bank_recess_y = 5;
  43
  44 strap_th = 3;
  45 strap_above = 2.5;
  46
  47 retainer_walls = [18, 30];
  48
  49 bank_profile_scale_bodge = 1.0;
  50
  51 bank_input_ctr = [ 12.5, 11.5 ]; // from nearest corner
  52 bank_input_sz  = [ 8.5, 10.5 ];
  53
  54 mounted_pos_y_offset = 20;
  55
  56 liner_th = 0.8;
  57
  58 brace_r = 5;
  59 brace_len = 50;
  60
  61 // calculated
  62
  63 straps_y = [ -bank_y_sz * 0.25,
  64              +bank_y_sz * 0.25 ];
  65
  66 screw_head_behind = main_th;
  67 endwall_th = main_th;
  68
  69 bank_recess_dx = minor_wall_min;
  70
  71 pspt_to_mm = 25.4 / 72;
  72
  73 main_r = tube_dia/2 + main_th;
  74
  75 screw_max_y_lhs = -main_r -screw_nut_across/2;
  76 screw_max_y_rhs = -main_r -knob_behind_across/2;
  77
  78 screw_y = min(screw_max_y_lhs,
  79               screw_max_y_rhs);
  80
  81 bot_y = screw_y -max( screw_nut_across, knob_behind_across/2 )
  82   -minor_wall_min;
  83
  84 holder_x_sz = bank_x_sz + bank_recess_dx*2;
  85 bank_bot_y = strap_above + strap_th;
  86 strap_r = strap_th;
  87
  88 brace_total_len = brace_len + main_th;
  89 brace_ctrs_y = [ straps_y[0] - (brace_r + strap_r/2),
  90                  straps_y[1] + (brace_r + strap_r/2) ];
  91
  92 clamp_width_actual = max(clamp_width, 0);
  93
  94 hinge_stride = (clamp_width_actual + hinge_gap_z) / hinge_lobes;
  95
  96 hinge_outer_r = hinge_around + hinge_pin/2;
  97 hinge_y = tube_dia/2 + hinge_outer_r;
  98
  99 echo(bot_y);
 100
 101 module TubePlan(){ circle(r = tube_dia/2); }
 102 module HingePinPlan(){ translate([0, hinge_y]) circle(r= hinge_pin/2); }
 103 module HingeBodyPlan(){ translate([0, hinge_y]) circle(r= hinge_outer_r); }
 104
 105 module TubeClampLeftPlan(){
 106   difference(){
 107     union(){
 108       polygon([[ 0,                      hinge_y + hinge_outer_r ],
 109                [ -(main_r + overlap_l),  hinge_y + hinge_outer_r ],
 110                [ -(main_r + overlap_l),  bot_y                   ],
 111                [ -clamp_gap/2,           bot_y                   ],
 112                [ -clamp_gap/2,           0,                      ],
 113                [ 0,                      0,                      ],
 114                ]);
 115       HingeBodyPlan();
 116     }
 117     TubePlan();
 118     HingePinPlan();
 119   }
 120 }
 121
 122 module TubeClampLeft() { ////toplevel
 123   linextr(-clamp_width_actual/2, clamp_width_actual/2)
 124     TubeClampLeftPlan();
 125 }
 126
 127 module TubeClampRightPlan(){
 128   difference(){
 129     union(){
 130       rectfromto([ clamp_gap/2,                   bot_y ],
 131                  [ clamp_gap/2 + behind_knob_th,  0     ]);
 132       intersection(){
 133         circle(r= main_r);
 134         union(){
 135           rectfromto([0,0],
 136                       main_r *  [5,5]);
 137           rectfromto([ clamp_gap/2, main_r*5 ],
 138                       main_r * [2,-5]);
 139         }
 140       }
 141       HingeBodyPlan();
 142     }
 143     TubePlan();
 144     HingePinPlan();
 145   }
 146 }
 147
 148 module Screws(){
 149   linextr_x_yz(-main_r*5, main_r*5)
 150     translate([screw_y, 0])
 151     circle(r= screw/2);
 152
 153   translate([0, screw_y, 0]) {
 154     linextr_x_yz(-(clamp_gap/2 + screw_nut_th), 0)
 155       square([screw_nut_across,
 156               screw_nut_across / cos(30) + bridge_slop*2],
 157              center=true);
 158
 159     linextr_x_yz(-200,
 160                  -(clamp_gap/2 + screw_nut_th + screw_head_behind))
 161       square([screw_head, screw_head + bridge_slop*2],
 162              center=true);
 163   }
 164 }
 165
 166 module SomeClamp(hinge_alt=false){
 167   difference(){
 168     linextr(-clamp_width_actual/2, clamp_width_actual/2)
 169       children(0);
 170
 171     Screws();
 172
 173     for (i=[0 : hinge_lobes-1]) {
 174       translate([0,
 175                  hinge_y,
 176                  -clamp_width_actual/2 + i * hinge_stride
 177                  + (hinge_alt ? hinge_stride/2 : 0)
 178                  ])
 179         linextr(-hinge_gap_z, hinge_stride/2)
 180         square(hinge_outer_r*2 + hinge_gap_xy, center=true);
 181     }
 182   }
 183 }
 184
 185 module PowerBankItselfSidePlan(){
 186   translate([0, bank_bot_y]){
 187     minkowski(){
 188       circle($fn=8, r=liner_th);
 189       scale( bank_profile_scale_bodge *
 190              bank_x_sz / ( (
 191                             bank_eps_bbox_x[1] -
 192                             bank_eps_bbox_x[0]
 193                             ) * pspt_to_mm ))
 194         translate(pspt_to_mm *
 195                   [-0.5 * (bank_eps_bbox_x[0] +
 196                            bank_eps_bbox_x[1]),
 197                    -bank_eps_bbox_y[0]])
 198         import("powerbank-anker-10000.dxf", convexity=5);
 199     }
 200   }
 201 }
 202
 203 module PowerBankItself(){ ////toplevel
 204   rotate([0,90,0])
 205     linextr_y_xz(-bank_y_sz/2,
 206                  +bank_y_sz/2)
 207     PowerBankItselfSidePlan();
 208 }
 209
 210 module PowerBankSidePlan(){ ////toplevel
 211   render() difference(){
 212     rectfromto([ -holder_x_sz/2,  0 ],
 213                [ +holder_x_sz/2,  bank_recess_y + bank_bot_y ]);
 214
 215     PowerBankItselfSidePlan();
 216   }
 217 }
 218
 219 module PowerBankStrapCut(){ ////toplevel
 220   difference(){
 221     rectfromto([ -holder_x_sz, -0.05 ],
 222                [ +holder_x_sz, strap_th + strap_r ]);
 223     hull(){
 224       for (sx=[-1,+1]) {
 225         translate([sx * (holder_x_sz/2 - strap_r + 0.1),
 226                    strap_th + strap_r])
 227           circle(strap_r);
 228       }
 229     }
 230   }
 231 }
 232
 233 module PowerBankHolderTest(){ ////toplevel
 234   difference(){
 235     linextr(-1,5) PowerBankSidePlan();
 236     linextr(0, strap_th) PowerBankStrapCut();
 237   }
 238 }
 239
 240 module EndRetainer(depth){ ////toplevel
 241   translate([0, -bank_y_sz/2, 0]) {
 242     linextr_y_xz(-endwall_th, 0)
 243     rectfromto([ 0,         -holder_x_sz/2 ],
 244                [ -depth,    +holder_x_sz/2 ]);
 245
 246     for (m=[0,1]) {
 247       mirror([0,0,m]) {
 248         linextr(-holder_x_sz/2, -bank_x_sz/2){
 249           hull(){
 250             rectfromto([ 0, -endwall_th ],
 251                        [ depth, 0 ]);
 252             rectfromto([ 0, 0 ],
 253                        [ 0.1, depth-0.1 ]);
 254           }
 255         }
 256       }
 257     }
 258   }
 259 }
 260
 261 module BraceTubePlan(){
 262   intersection(){
 263     circle(r= brace_r);
 264     rectfromto(brace_r * [-2,  0],
 265                brace_r * [+2, +2]);
 266   }
 267 }
 268
 269 module PowerBankHolder(){ ////toplevel
 270   difference(){
 271     union(){
 272       rotate([0,90,0])
 273         linextr_y_xz(-(bank_y_sz/2 + 0.1),
 274                      +(bank_y_sz/2 + 0.1))
 275         PowerBankSidePlan();
 276
 277       EndRetainer(retainer_walls[0]);
 278       mirror([0,1,0]) EndRetainer(retainer_walls[1]);
 279     }
 280
 281     for (strap_y = straps_y)
 282       translate([0, strap_y, 0])
 283         rotate([0,0,-90])
 284         rotate([0,90,0])
 285         linextr(-strap_th/2,
 286                 +strap_th/2)
 287         PowerBankStrapCut();
 288
 289     translate([ bank_bot_y, -bank_y_sz/2, -bank_x_sz/2 ])
 290       linextr_y_xz(-50,50)
 291        rotate([0,0,90])
 292        translate(bank_input_ctr)
 293        square(center=true, bank_input_sz);
 294   }
 295
 296   translate([0,0, bank_x_sz/2]){
 297     for (y = brace_ctrs_y) {
 298       translate([0,y,0]) {
 299         linextr_x_yz(0, brace_total_len)
 300           BraceTubePlan();
 301       }
 302     }
 303     translate([brace_total_len, 0,0])
 304       linextr_y_xz(brace_ctrs_y[0] - brace_r,
 305                    brace_ctrs_y[1] + brace_r)
 306       BraceTubePlan();
 307   }
 308 }
 309
 310 module TubeClampLeft() { ////toplevel
 311   // We want this to print with the recess overhand to the right
 312   // where the workpiece cooling fan is
 313   rotate([0,0,180]){
 314     difference(){
 315       SomeClamp(true)
 316         TubeClampLeftPlan();
 317
 318       Screws();
 319     }
 320   }
 321 }
 322
 323 module Main(){ ////toplevel
 324   TubeClampLeft();
 325   difference(){
 326     translate([main_r, -mounted_pos_y_offset, 0])
 327       PowerBankHolder();
 328     rotate([0,0,180])
 329       Screws();
 330   }
 331 }
 332
 333 module TubeClampRight() { ////toplevel
 334   rotate([0,0,180])
 335     rotate([180,0,0])
 336     SomeClamp()
 337     TubeClampRightPlan();
 338 }
 339
 340 module TubeClampDemo() { ////toplevel
 341   TubeClampLeft();
 342   rotate([180,0,0])
 343     TubeClampRight();
 344 }