box_frame/bushing.scad

   1 // PRUSA iteration3
   2 // Bushing/bearing housings
   3 // GNU GPL v3
   4 // Josef Průša <josefprusa@me.com>
   5 // Václav 'ax' Hůla <axtheb@gmail.com>
   6 // http://www.reprap.org/wiki/Prusa_Mendel
   7 // http://github.com/prusajr/PrusaMendel
   8
   9 include <configuration.scad>
  10
  11 // ensure that the part length is at least the length of bushing barrel plus add
  12 function adjust_bushing_len(conf_b, h, add=layer_height*2) = ((conf_b[2]+add) > h) ? conf_b[2]+add : h;
  13
  14 //distance from the flat side of bushing holder to rod center
  15 function bushing_foot_len(conf_b, h=10.5, add=4*single_wall_width) = ((conf_b[1]+add) > h) ? conf_b[1]+add : h;
  16
  17 function bushing_outer_radius(conf_b) = conf_b[1] + 4*single_wall_width;
  18
  19 // basic building blocks, housings for 1 bushing/bearing
  20 // at [0,0] there is center of the smooth rod, pointing in Z
  21
  22 module linear_bushing_negative_single(conf_b=bushing_xy, h=0){
  23     // barrel with the dimensions of a bushing/bearing
  24     // to be substracted as needed
  25     translate([0, 0, -0.01])  cylinder(r = conf_b[1], h = adjust_bushing_len(conf_b, h) + 0.02);
  26 }
  27
  28 module linear_bearing_negative_single(conf_b=bushing_xy, h=0, shadow=false){
  29     // barrel with the dimensions of the bearing
  30     translate([0, 0, -0.01 + 3 * layer_height])  cylinder(r = conf_b[1], h = adjust_bushing_len(conf_b, h) + 0.02);
  31     if (shadow == false) {
  32         translate([0, -conf_b[1]+1, -0.01 + 3 * layer_height]) cube([30, 2 * conf_b[1] - 2, adjust_bushing_len(conf_b, h) + 0.02]);
  33     }
  34 }
  35
  36 module linear_bushing_single(conf_b=bushing_xy, h=0) {
  37     // This is the printed barrel around bushing
  38     // with foot pointing to -x
  39     translate([-bushing_foot_len(conf_b), -7, 0]) cube([bushing_foot_len(conf_b), 14, adjust_bushing_len(conf_b, h)]);
  40     cylinder(r=bushing_outer_radius(conf_b), h=adjust_bushing_len(conf_b, h));
  41 }
  42
  43 module linear_bushing_negative(conf_b=bushing_xy, h=0){
  44     // return simple negative stretched all along and a smooth rod
  45     translate([0,0,-0.1]) cylinder(r = conf_b[0] + single_wall_width, h=adjust_bushing_len(conf_b, h)+0.2);
  46     linear_bushing_negative_single(conf_b, h=adjust_bushing_len(conf_b, h));
  47 }
  48
  49 module linear_bearing_negative(conf_b = bushing_xy, h = 0, shadow=false){
  50     //same as linear_bushing_negative, but with z direction constrained parts
  51     translate([0,0,-0.1]) cylinder(r = conf_b[0] + single_wall_width, h=adjust_bushing_len(conf_b, h, 8*layer_height)+0.2);
  52     //lower bearing
  53     linear_bearing_negative_single(conf_b, 0, shadow);
  54     if (h > 2*conf_b[2] + 9*layer_height){
  55         translate([0,0,h]) mirror([0,0,1]) linear_bearing_negative_single(conf_b, 0, shadow);
  56     }
  57 }
  58
  59 module linear_negative_preclean(conf_b = bushing_xy) {
  60     // makes sure there is nothing interfering
  61     // to be substracted before linear()
  62     cylinder(r = conf_b[1] + single_wall_width, h=300, center=true);
  63 }
  64
  65 module linear_bushing_sloped(conf_b=bushing_xy, h= 100){
  66     // cut the bushing at angle, so it can be printed upside down
  67     intersection(){
  68         linear_bushing_single(conf_b, h = h);
  69         // hardcoded, may need fixing for different barelled bushings
  70         // atm there is only one and I am too lazy
  71         translate([0, 0, -2]) rotate([0,-50,0]) cube([30, 40, 80], center=true);
  72     }
  73 }
  74
  75 module linear_bushing(conf_b=bushing_xy, h=0){
  76     // this is the function to be used for type 1 linears (barrel holder)
  77     // It has bushing on bottom and for parts longer than 3x the barel length on top too
  78     difference() {
  79         union() {
  80             translate([-bushing_foot_len(conf_b), -7, 0]) cube([2, 14, adjust_bushing_len(conf_b, h)]);
  81             linear_bushing_single(conf_b);
  82             if (h>3*conf_b[2]) {
  83                 translate([0,0,h]) mirror([0,0,1]) linear_bushing_sloped(conf_b);
  84             }
  85         }
  86         linear_bushing_negative(conf_b, h);
  87     }
  88 }
  89
  90 module linear_bearing(conf_b=bushing_xy, h=0){
  91     difference() {
  92         union() {
  93             difference(){
  94                 union(){
  95                     //main block
  96                     //translate([-bushing_foot_len(conf_b), -7, 0]) cube([4, 14, adjust_bushing_len(conf_b, h, 9*layer_height)]);   <- removed for duplicity:)
  97                     translate([0,0,0]) cylinder(h = adjust_bushing_len(conf_b, h, 9*layer_height), r=bushing_outer_radius(conf_b), $fn=60);
  98                 }
  99                 //smooth entry cut
 100                 translate([12,0,-1]) rotate([0,0,45]) cube([20, 20, 200], center=true);
 101             }
 102             intersection(){
 103                 translate([0, -(bushing_outer_radius(conf_b)), 0]) cube([30, 2*bushing_outer_radius(conf_b) , max(h, conf_b[2] + 9 * layer_height)]);
 104                 union() {
 105                     // upper clamp for long holders
 106                     if (h > 2*conf_b[2] + 9*layer_height || conf_b[2] > 45){
 107                         translate ([0,0, max(h, conf_b[2]) - 8 ]) bearing_clamp(conf_b, 2*(bushing_outer_radius(conf_b)));
 108                     }
 109                     //lower clamp
 110                     translate ([0, 0, 10]) bearing_clamp(conf_b, 2*(bushing_outer_radius(conf_b)));
 111                 }
 112             }
 113         }
 114         //main axis
 115         translate([0,0,-2]) cylinder(h = adjust_bushing_len(conf_b, h)+10, r=conf_b[1]);
 116         //main cut
 117         translate([0, -conf_b[1]+1, -1]) cube([30, 2*conf_b[1]-2, 200]);
 118     }
 119     difference() {
 120         translate([-bushing_foot_len(conf_b), -7, 0]) cube([4, 14, adjust_bushing_len(conf_b, h, 9*layer_height)]);
 121         linear_negative(conf_b, h);
 122     }
 123 }
 124
 125 // this should be more parametric
 126 module firm_foot(conf_b = conf_b_lm8uu){
 127     difference(){
 128         union() {
 129             translate([8.5/2,0,0]) cube_fillet([8.5, 42 + xy_delta * 2, 20], top=[11, 0, 11, 0], center=true);
 130         }
 131         translate([9, 14.5 + xy_delta, 0]) rotate([0, -90, 0]) screw(head_drop=1, $fn=small_hole_segments);
 132         translate([9,-14.5 - xy_delta, 0]) rotate([0,-90,0]) screw(head_drop=1,$fn=small_hole_segments);
 133     }
 134 }
 135
 136 module y_bearing(conf_b=bushing_xy){
 137
 138     difference() {
 139         union() {
 140             difference() {
 141                 union() {
 142                     translate([-bushing_foot_len(conf_b), 0, 10]) firm_foot();
 143                     if (bushing_xy[2] > 45) {
 144                         translate([-bushing_foot_len(conf_b), 0, adjust_bushing_len(bushing_xy, 45) - 8]) mirror([0, 0, 1]) firm_foot();
 145                     }
 146                 }
 147                 linear_negative_preclean();
 148             }
 149             linear();
 150         }
 151         //linear_negative(bushing_xy, 20);
 152     }
 153 }
 154
 155 module bearing_clamp_brick(conf_b, h){
 156     translate([-(m4_nut_diameter/2+conf_b[1]), 0, 0])
 157         cube([m4_nut_diameter + 2 * conf_b[1], m4_nut_diameter + 1, h], center = true);
 158 }
 159
 160 module bearing_clamp(conf_b=bushing_xy, h=0){
 161     // inspired by John Ridley and Jonas Kühling
 162     rotate([90, 0, 0]) {
 163         difference(){
 164             union(){
 165                 translate([m3_diameter / 2 + conf_b[1] + 0.3, 0, 0])
 166                     cylinder(h=h, r = m4_nut_diameter / 2 + 0.5, center = true);
 167                 translate([m3_diameter / 2 + conf_b[1] + 0.3, 0, 0]) {
 168                     bearing_clamp_brick(conf_b, h);
 169                     rotate([0,0,35])
 170                         bearing_clamp_brick(conf_b, h);
 171                 }
 172             }
 173             translate([m3_diameter / 2 + conf_b[1] + 0.3, 0, 0]) {
 174                 cylinder(r=m3_diameter / 2, h=h+2, center=true,$fn=small_hole_segments);
 175                 %cylinder(r=m3_diameter / 2, h=h+2, center=true,$fn=small_hole_segments);
 176             }
 177         }
 178     }
 179 }
 180
 181
 182 module linear_negative(conf_b = bushing_xy, h = 0, shadow=false){
 183     //selects right negative based on type
 184     if (conf_b[3] == 0) {
 185         linear_bearing_negative(conf_b, h, shadow);
 186     } else {
 187         linear_bushing_negative(conf_b, h, shadow);
 188     }
 189 }
 190
 191 module linear(conf_b = bushing_xy, h = 0){
 192     //selects right model based on type
 193     if (conf_b[3] == 0) {
 194         linear_bearing(conf_b, h);
 195     } else {
 196         linear_bushing(conf_b, h);
 197     }
 198     %linear_negative(conf_b, h, true);
 199 }
 200
 201 if (i_am_box == 1) {
 202     %cylinder(r=bushing_xy[0], h=90);
 203
 204     y_bearing();
 205     translate([0,52,0]) y_bearing();
 206
 207     if (bushing_xy[2] < 45) {
 208         translate ([-30,23,0]) mirror([1,0,0]) y_bearing();
 209     }
 210 } else {
 211     cube([0.1, 0.1, 0.1]);
 212 }