powerbank-bike-clamp.scad

   1 // -*- C -*-
   2
   3 // Print one of each:
   4 //    Main
   5 //    TubeClampRight
   6
   7 include <utils.scad>
   8
   9 tube_dia = 22.4;
  10
  11 hinge_around = 2.5;
  12 hinge_pin = 1.8 + 0.75;
  13 main_th = 3;
  14 minor_wall_min = 1;
  15
  16 screw = 5.0 + 0.75;
  17 screw_head = 8.7 + 1.2;
  18 screw_nut_across = 7.9 + 0.75;
  19 screw_nut_th = 3.9 + 0.75;
  20
  21 knob_behind_across = 12.2 + 0.75;
  22 behind_knob_th = 5;
  23 knob_standout_h = 2;
  24
  25 clamp_min_width = 20;
  26
  27 clamp_gap = 2;
  28
  29 lower_th = 1;
  30
  31 overlap_l = 0.1;
  32
  33 bridge_slop = 1.2;
  34
  35 hinge_lobe_per = 10;
  36 hinge_gap_z = 0.75;
  37 hinge_gap_xy = 0.75;
  38
  39 $fs = 0.1;
  40 $fa = 5;
  41
  42 bank_eps_bbox_x = [149, 598];
  43 bank_eps_bbox_y = [274, 1452];
  44
  45 bank_y_sz = 102.25 + 0.50 + 3.2;
  46 bank_x_sz = (26.0 + 0.5);
  47 bank_recess_y = 5;
  48
  49 strap_th = 3;
  50 strap_w = 5;
  51 strap_above = 2.5;
  52
  53 retainer_walls = [18, 30];
  54
  55 bank_profile_scale_bodge = 1.0;
  56
  57 bank_input_ctr = [ 12.5, 11.5 ]; // from nearest corner
  58 bank_input_sz  = [ 8.5, 10.5 ];
  59
  60 mounted_pos_y_offset = 20;
  61
  62 liner_th = 0.8;
  63
  64 brace_r = 5;
  65 brace_len = 50;
  66
  67 // calculated
  68
  69 straps_y = [ -bank_y_sz * 0.25,
  70              +bank_y_sz * 0.25 ];
  71
  72 screw_head_behind = main_th;
  73 endwall_th = main_th;
  74
  75 bank_recess_dx = minor_wall_min;
  76
  77 pspt_to_mm = 25.4 / 72;
  78
  79 main_r = tube_dia/2 + main_th;
  80
  81 screw_max_y_lhs = -main_r -screw_nut_across/2;
  82 screw_max_y_rhs = -main_r -knob_behind_across/2;
  83
  84 screw_y = min(screw_max_y_lhs,
  85               screw_max_y_rhs);
  86
  87 bot_y = screw_y -max( screw_nut_across/2, knob_behind_across/2 )
  88   -minor_wall_min;
  89
  90 holder_x_sz = bank_x_sz + bank_recess_dx*2;
  91 bank_bot_y = strap_above + strap_th;
  92 strap_r = strap_th;
  93
  94 brace_total_len = brace_len + main_th;
  95 brace_ctrs_y = [ straps_y[0] - (brace_r + strap_w/2),
  96                  straps_y[1] + (brace_r + strap_w/2) ];
  97
  98 clamp_width_actual = max(clamp_min_width, holder_x_sz);
  99
 100 hinge_lobes = floor(clamp_width_actual / hinge_lobe_per);
 101 hinge_stride = (clamp_width_actual + hinge_gap_z) / hinge_lobes;
 102
 103 hinge_outer_r = hinge_around + hinge_pin/2;
 104 hinge_y = tube_dia/2 + hinge_outer_r;
 105
 106 top_cnr_r = min(endwall_th, main_th);
 107
 108 echo(bot_y);
 109
 110 module TubePlan(){ circle(r = tube_dia/2); }
 111 module HingePinPlan(){ translate([0, hinge_y]) circle(r= hinge_pin/2); }
 112 module HingeBodyPlan(){ translate([0, hinge_y]) circle(r= hinge_outer_r); }
 113
 114 module TubeClampLeftPlan(){
 115   difference(){
 116     union(){
 117       polygon([[ 0,                      hinge_y + hinge_outer_r ],
 118                [ -(main_r + overlap_l),  hinge_y + hinge_outer_r ],
 119                [ -(main_r + overlap_l),  bot_y                   ],
 120                [ -clamp_gap/2,           bot_y                   ],
 121                [ -clamp_gap/2,           0,                      ],
 122                [ 0,                      0,                      ],
 123                ]);
 124       HingeBodyPlan();
 125     }
 126     TubePlan();
 127     HingePinPlan();
 128   }
 129 }
 130
 131 module TubeClampLeft() { ////toplevel
 132   linextr(-clamp_width_actual/2, clamp_width_actual/2)
 133     TubeClampLeftPlan();
 134 }
 135
 136 module TubeClampRightPlan(){
 137   difference(){
 138     union(){
 139       rectfromto([ clamp_gap/2,                   bot_y ],
 140                  [ clamp_gap/2 + behind_knob_th,  0     ]);
 141       intersection(){
 142         circle(r= main_r);
 143         union(){
 144           rectfromto([0,0],
 145                       main_r *  [5,5]);
 146           rectfromto([ clamp_gap/2, main_r*5 ],
 147                       main_r * [2,-5]);
 148         }
 149       }
 150       HingeBodyPlan();
 151     }
 152     TubePlan();
 153     HingePinPlan();
 154   }
 155 }
 156
 157 module Screws(){
 158   linextr_x_yz(-main_r*5, main_r*5)
 159     translate([screw_y, 0])
 160     circle(r= screw/2);
 161
 162   translate([0, screw_y, 0]) {
 163     linextr_x_yz(-(clamp_gap/2 + screw_nut_th), 0)
 164       square([screw_nut_across,
 165               screw_nut_across / cos(30) + bridge_slop*2],
 166              center=true);
 167
 168     linextr_x_yz(-200,
 169                  -(clamp_gap/2 + screw_nut_th + screw_head_behind))
 170       square([screw_head, screw_head + bridge_slop*2],
 171              center=true);
 172   }
 173 }
 174
 175 module SomeClamp(hinge_alt=false){
 176   difference(){
 177     linextr(-clamp_width_actual/2, clamp_width_actual/2)
 178       children(0);
 179
 180     Screws();
 181
 182     for (i=[0 : hinge_lobes-1]) {
 183       translate([0,
 184                  hinge_y,
 185                  -clamp_width_actual/2 + i * hinge_stride
 186                  + (hinge_alt ? hinge_stride/2 : 0)
 187                  ])
 188         linextr(-hinge_gap_z, hinge_stride/2)
 189         square(hinge_outer_r*2 + hinge_gap_xy, center=true);
 190     }
 191   }
 192 }
 193
 194 module PowerBankItselfSidePlan(){
 195   translate([0, bank_bot_y]){
 196     minkowski(){
 197       circle($fn=8, r=liner_th);
 198       scale( bank_profile_scale_bodge *
 199              bank_x_sz / ( (
 200                             bank_eps_bbox_x[1] -
 201                             bank_eps_bbox_x[0]
 202                             ) * pspt_to_mm ))
 203         translate(pspt_to_mm *
 204                   [-0.5 * (bank_eps_bbox_x[0] +
 205                            bank_eps_bbox_x[1]),
 206                    -bank_eps_bbox_y[0]])
 207         import("powerbank-anker-10000.dxf", convexity=5);
 208     }
 209   }
 210 }
 211
 212 module PowerBankItself(){ ////toplevel
 213   rotate([0,90,0])
 214     linextr_y_xz(-bank_y_sz/2,
 215                  +bank_y_sz/2)
 216     PowerBankItselfSidePlan();
 217 }
 218
 219 module PowerBankSidePlan(){ ////toplevel
 220   render() difference(){
 221     rectfromto([ -holder_x_sz/2,  0 ],
 222                [ +holder_x_sz/2,  bank_recess_y + bank_bot_y ]);
 223
 224     PowerBankItselfSidePlan();
 225   }
 226 }
 227
 228 module PowerBankStrapCut(){ ////toplevel
 229   difference(){
 230     rectfromto([ -holder_x_sz, -0.05 ],
 231                [ +holder_x_sz, strap_th + strap_r ]);
 232     hull(){
 233       for (sx=[-1,+1]) {
 234         translate([sx * (holder_x_sz/2 - strap_r + 0.1),
 235                    strap_th + strap_r])
 236           circle(strap_r);
 237       }
 238     }
 239   }
 240 }
 241
 242 module PowerBankHolderTest(){ ////toplevel
 243   difference(){
 244     linextr(-1,5) PowerBankSidePlan();
 245     linextr(0, strap_w) PowerBankStrapCut();
 246   }
 247 }
 248
 249 module EndRetainer(depth){ ////toplevel
 250   translate([0, -bank_y_sz/2, 0]) {
 251     linextr_y_xz(-endwall_th, 0)
 252     rectfromto([ 0,         -holder_x_sz/2 ],
 253                [ -depth,    +holder_x_sz/2 ]);
 254
 255     for (m=[0,1]) {
 256       mirror([0,0,m]) {
 257         linextr(-holder_x_sz/2, -bank_x_sz/2){
 258           hull(){
 259             rectfromto([ 0, -endwall_th ],
 260                        [ depth, 0 ]);
 261             rectfromto([ 0, 0 ],
 262                        [ 0.1, depth-0.1 ]);
 263           }
 264         }
 265       }
 266     }
 267   }
 268 }
 269
 270 module BraceTubePlan(){
 271   intersection(){
 272     circle(r= brace_r);
 273     rectfromto(brace_r * [-2,  0],
 274                brace_r * [+2, +2]);
 275   }
 276 }
 277
 278 module PowerBankHolder(){ ////toplevel
 279   difference(){
 280     union(){
 281       rotate([0,90,0])
 282         linextr_y_xz(-(bank_y_sz/2 + 0.1),
 283                      +(bank_y_sz/2 + 0.1))
 284         PowerBankSidePlan();
 285
 286       EndRetainer(retainer_walls[0]);
 287       mirror([0,1,0]) EndRetainer(retainer_walls[1]);
 288
 289       translate([0,0, bank_x_sz/2]){
 290         for (y = brace_ctrs_y) {
 291           translate([0,y,0]) {
 292             linextr_x_yz(0, brace_total_len)
 293               BraceTubePlan();
 294           }
 295         }
 296         translate([brace_total_len, 0,0])
 297           linextr_y_xz(brace_ctrs_y[0] - brace_r,
 298                        brace_ctrs_y[1] + brace_r)
 299           BraceTubePlan();
 300       }
 301     }
 302
 303     for (strap_y = straps_y)
 304       translate([0, strap_y, 0])
 305         rotate([0,0,-90])
 306         rotate([0,90,0])
 307         linextr(-strap_w/2,
 308                 +strap_w/2)
 309         PowerBankStrapCut();
 310
 311     translate([ bank_bot_y, -bank_y_sz/2, -bank_x_sz/2 ])
 312       linextr_y_xz(-50,50)
 313        rotate([0,0,90])
 314        translate(bank_input_ctr)
 315        square(center=true, bank_input_sz);
 316
 317     translate([0, -(bank_y_sz/2 + endwall_th), 0] + 0.01 * [-1,-1]) {
 318       linextr(-200,200){
 319         difference(){
 320           square(center=true, top_cnr_r*2);
 321           translate(top_cnr_r * [1,1])
 322             circle(r= top_cnr_r);
 323         }
 324       }
 325     }
 326   }
 327 }
 328
 329 module TubeClampLeft() { ////toplevel
 330   // We want this to print with the recess overhand to the right
 331   // where the workpiece cooling fan is
 332   rotate([0,0,180]){
 333     difference(){
 334       SomeClamp(true)
 335         TubeClampLeftPlan();
 336
 337       Screws();
 338     }
 339   }
 340 }
 341
 342 module PlacePowerBank(){
 343   translate([main_r, -mounted_pos_y_offset, 0])
 344     children(0);
 345 }
 346
 347 module Main(){ ////toplevel
 348   TubeClampLeft();
 349   difference(){
 350     PlacePowerBank()
 351       PowerBankHolder();
 352     rotate([0,0,180])
 353       Screws();
 354   }
 355 }
 356
 357 module TubeClampRight() { ////toplevel
 358   rotate([0,0,180]) {
 359     rotate([180,0,0]) {
 360       difference(){
 361         union(){
 362           SomeClamp()
 363             TubeClampRightPlan();
 364
 365           translate([clamp_gap/2 + behind_knob_th, screw_y, 0]) {
 366             hull(){
 367               linextr_x_yz(-0.1, 0)
 368                 square(center=true,
 369                        [knob_behind_across,
 370                         knob_behind_across + knob_standout_h*2]);
 371               linextr_x_yz(0, knob_standout_h)
 372                 square(center=true,
 373                        knob_behind_across);
 374             }
 375           }
 376         }
 377         Screws();
 378       }
 379     }
 380   }
 381 }
 382
 383 module TubeClampDemo() { ////toplevel
 384   TubeClampLeft();
 385   rotate([180,0,0])
 386     TubeClampRight();
 387 }
 388
 389 module Demo() { ////toplevel
 390   Main();
 391   rotate([180,0,0])
 392     TubeClampRight();
 393   PlacePowerBank()
 394     %PowerBankItself();
 395 }