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_x_sz = (24.9 + 0.5);
  42 bank_recess_y = 5;
  43 bank_recess_dx = 3;
  44
  45 strap_th = 3;
  46 strap_above = 2.5;
  47
  48 // calculated
  49
  50 pspt_to_mm = 25.4 / 72;
  51
  52 hinge_stride = (clamp_width + hinge_gap_z) / hinge_lobes;
  53
  54 main_r = tube_dia/2 + main_th;
  55
  56 hinge_outer_r = hinge_around + hinge_pin/2;
  57 hinge_y = tube_dia/2 + hinge_outer_r;
  58
  59 screw_max_y_lhs = -main_r -screw_nut_across/2;
  60 screw_max_y_rhs = -main_r -knob_behind_across/2;
  61
  62 screw_y = min(screw_max_y_lhs,
  63               screw_max_y_rhs);
  64
  65 bot_y = screw_y -max( screw_nut_across, knob_behind_across/2 )
  66   -minor_wall_min;
  67
  68 holder_x_sz = bank_x_sz + bank_recess_dx*2;
  69 bank_bot_y = strap_above + strap_th;
  70
  71 echo(bot_y);
  72
  73 module TubePlan(){ circle(r = tube_dia/2); }
  74 module HingePinPlan(){ translate([0, hinge_y]) circle(r= hinge_pin/2); }
  75 module HingeBodyPlan(){ translate([0, hinge_y]) circle(r= hinge_outer_r); }
  76
  77 module TubeClampLeftPlan(){
  78   difference(){
  79     union(){
  80       polygon([[ 0,                    hinge_y + hinge_outer_r ],
  81                [ -main_r + overlap_l,  hinge_y + hinge_outer_r ],
  82                [ -main_r + overlap_l,  bot_y                   ],
  83                [ -clamp_gap/2,         bot_y                   ],
  84                [ -clamp_gap/2,         0,                      ],
  85                [ 0,                    0,                      ],
  86                ]);
  87       HingeBodyPlan();
  88     }
  89     TubePlan();
  90     HingePinPlan();
  91   }
  92 }
  93
  94 module TubeClampLeft() { ////toplevel
  95   linextr(-clamp_width/2, clamp_width/2)
  96     TubeClampLeftPlan();
  97 }
  98
  99 module TubeClampRightPlan(){
 100   difference(){
 101     union(){
 102       rectfromto([ clamp_gap/2,                   bot_y ],
 103                  [ clamp_gap/2 + behind_knob_th,  0     ]);
 104       intersection(){
 105         circle(r= main_r);
 106         union(){
 107           rectfromto([0,0],
 108                       main_r *  [5,5]);
 109           rectfromto([ clamp_gap/2, main_r*5 ],
 110                       main_r * [2,-5]);
 111         }
 112       }
 113       HingeBodyPlan();
 114     }
 115     TubePlan();
 116     HingePinPlan();
 117   }
 118 }
 119
 120 module SomeClamp(hinge_alt=false){
 121   difference(){
 122     linextr(-clamp_width/2, clamp_width/2)
 123       children(0);
 124
 125     linextr_x_yz(-main_r*5, main_r*5)
 126       translate([screw_y, 0])
 127       circle(r= screw/2);
 128
 129     for (i=[0 : hinge_lobes-1]) {
 130       translate([0,
 131                  hinge_y,
 132                  -clamp_width/2 + i * hinge_stride
 133                  + (hinge_alt ? hinge_stride/2 : 0)
 134                  ])
 135         linextr(-hinge_gap_z, hinge_stride/2)
 136         square(hinge_outer_r*2 + hinge_gap_xy, center=true);
 137     }
 138   }
 139 }
 140
 141 module PowerBankItselfSidePlan(){
 142   translate([0, bank_bot_y])
 143     scale( bank_x_sz / ( (
 144                           bank_eps_bbox_x[1] -
 145                           bank_eps_bbox_x[0]
 146                           ) * pspt_to_mm ))
 147     translate(pspt_to_mm *
 148               [-0.5 * (bank_eps_bbox_x[0] +
 149                        bank_eps_bbox_x[1]),
 150                -bank_eps_bbox_y[0]])
 151     import("powerbank-anker-10000.dxf", convexity=5);
 152 }
 153
 154 module PowerBankSidePlan(){ ////toplevel
 155   render() difference(){
 156     rectfromto([ -holder_x_sz/2,  0 ],
 157                [ +holder_x_sz/2,  bank_recess_y + bank_bot_y ]);
 158
 159     PowerBankItselfSidePlan();
 160   }
 161 }
 162 /*
 163 module PowerBankStrapNocut(){ ////toplevel
 164   hull(){
 165     for (sx=[-1,+1]) {
 166       translate(
 167 */
 168 module PowerBankHolderTest(){ ////toplevel
 169
 170 }
 171
 172 module TubeClampLeft() { ////toplevel
 173   difference(){
 174     SomeClamp(true)
 175       TubeClampLeftPlan();
 176
 177     translate([0, screw_y, 0]) {
 178       linextr_x_yz(-(clamp_gap/2 + screw_nut_th), 0)
 179         square([screw_nut_across,
 180                 screw_nut_across / cos(30) + bridge_slop*2],
 181                center=true);
 182
 183       linextr_x_yz(-main_r, -main_r + screw_head_h)
 184         square([screw_head, screw_head + bridge_slop*2],
 185                center=true);
 186     }
 187   }
 188 }
 189
 190 module TubeClampRight() { ////toplevel
 191   rotate([180,0,0])
 192     SomeClamp()
 193     TubeClampRightPlan();
 194 }
 195
 196 module TubeClampDemo() { ////toplevel
 197   TubeClampLeft();
 198   rotate([180,0,0])
 199     TubeClampRight();
 200 }