Tweaks to make interface consistent with blowers.

Added blower_exit_offset().
Fixed corner shape and exit dimensions.
Updated images and readme.

readme.md

@@ -296,11 +296,18 @@ Models of radial blowers.
 | ```blower_wall(type)``` | Side wall thickness |
 | ```blower_width(type)``` | Width of enclosing rectangle |
 
+### Functions
+| Function | Description |
+|:--- |:--- |
+| ```blower_casing_is_square(type)``` | True for square radial fans, false for spiral shape radial blowers |
+| ```blower_exit_offset(type)``` | Offset of exit's centre from the edge |
+
 ### Modules
 | Module | Description |
 |:--- |:--- |
 | ```blower(type)``` | Draw specified blower |
 | ```blower_hole_positions(type)``` | Translate children to screw hole positions |
+| ```blower_square(type)``` | Draw a square blower |
 
 ![blowers](tests/png/blowers.png)
 
@@ -309,8 +316,11 @@ Models of radial blowers.
 | ---:|:--- |:---|
 |   1 | ```blower(PE4020)``` |  Blower Pengda Technology 4020 |
 |   1 | ```blower(RB5015)``` |  Blower Runda RB5015 |
+|   4 | ```screw(M2_cap_screw, 8)``` |  Screw M2 cap x  8mm |
 |   3 | ```screw(M3_cap_screw, 20)``` |  Screw M3 cap x 20mm |
 |   2 | ```screw(M4_cap_screw, 25)``` |  Screw M4 cap x 25mm |
+|   1 | ```blower(BL40x10)``` |  Square radial 4010 |
+|   4 | ```washer(M2_washer)``` |  Washer  M2 x 5mm x 0.3mm |
 |   3 | ```washer(M3_washer)``` |  Washer  M3 x 7mm x 0.5mm |
 |   2 | ```washer(M4_washer)``` |  Washer  M4 x 9mm x 0.8mm |
 

vitamins/blower.scad

@@ -22,6 +22,7 @@
 //
 include <../utils/core/core.scad>
 use <../utils/rounded_cylinder.scad>
+use <../utils/quadrant.scad>
 use <screw.scad>
 
 function blower_length(type)      = type[2]; //! Length of enclosing rectangle
@@ -40,6 +41,9 @@ function blower_top(type)         = type[14]; //! Thickness of the top
 function blower_wall(type)        = type[15]; //! Side wall thickness
 function blower_lug(type)         = type[16]; //! Height of the lugs
 
+function blower_casing_is_square(type) = len(blower_screw_holes(type)) > 3; //! True for square radial fans, false for spiral shape radial blowers
+function blower_exit_offset(type) = blower_casing_is_square(type) ? blower_length(type) / 2 : blower_exit(type) / 2; //! Offset of exit's centre from the edge
+
 fan_colour = grey(20);
 
 module blower_fan(type, casing_is_square) {
@@ -73,17 +77,18 @@ module blower_square(type) { //! Draw a square blower
     wall = blower_wall(type);
     hole_pitch = (blower_screw_holes(type)[1].x - blower_screw_holes(type)[0].x) / 2;
     corner_radius = width / 2 - hole_pitch;
-    corner_inset = (width - blower_exit(type) - blower_wall(type)) / 2;
+    corner_inset = (width - blower_exit(type)) / 2;
 
     module square_inset_corners(remove_center = false)
         difference() {
             //overall outside
-            translate([0, eps, 0]) // eps y value required or difference fails, bug in OpenSCAD?
                 square([width, width], center = false);
+
             if (remove_center) {
                 // cut out the inside, leaving the corners
-                translate([corner_inset + wall, 0])
+                translate([corner_inset + wall, -eps])
-                    square([width - 2 * (wall + corner_inset), width - wall], center = false);
+                    square([width - 2 * (wall + corner_inset), width - wall + eps], center = false);
+
                 translate([wall, corner_inset + wall])
                     square([width - 2 * wall, width - 2 * (wall + corner_inset)], center = false);
             } else {
@@ -92,21 +97,26 @@ module blower_square(type) { //! Draw a square blower
                     circle(d = blower_bore(type));
             }
             // corner inset
-            for (x = [0, width], y = [0, width])
+            translate([width / 2, width / 2])
-                translate([x , y])
+            for(i = [0 : 3])
-                    circle(r = corner_inset);
+                rotate(i * 90)
+                    translate([-width / 2 - eps, -width/ 2 - eps])
+                        quadrant(corner_inset, corner_inset - corner_radius);
         }
 
     base_height = blower_base(type);
     linear_extrude(base_height)
         difference () {
             rounded_square([width, width], corner_radius, center = false);
+
             blower_hole_positions(type)
                 circle(d = blower_screw_hole(type));
         }
+
     translate_z(base_height)
         linear_extrude(depth - base_height)
             square_inset_corners(remove_center = true);
+
     translate_z(depth - base_height)
         linear_extrude(blower_top(type))
             square_inset_corners();
@@ -141,7 +151,7 @@ module blower(type) { //! Draw specified blower
 
     vitamin(str("blower(", type[0], "): ", type[1]));
 
-    is_square = blower_lug(type) == 0; // it's a square blower if there are no lugs
+    is_square = blower_casing_is_square(type); // Description starts with square!
     color(fan_colour) {
         if (is_square) {
             blower_square(type);
@@ -173,6 +183,7 @@ module blower(type) { //! Draw specified blower
                     translate(concat(blower_axis(type), [blower_base(type)]))
                         circle(d = 2);
             }
+
             // sides
             linear_extrude(depth)
                 difference() {
@@ -195,6 +206,7 @@ module blower(type) { //! Draw specified blower
         // rotor
         translate(concat(blower_axis(type), [blower_base(type) + 1]))
             rounded_cylinder(r = blower_hub(type) / 2, h = blower_hub_height(type) - blower_base(type) - 1, r2 = 1);
+
         blower_fan(type, is_square);
     }
 }

vitamins/blowers.scad

@@ -16,15 +16,15 @@
 // You should have received a copy of the GNU General Public License along with NopSCADlib.
 // If not, see <https://www.gnu.org/licenses/>.
 //
-//                                                    l     w   d   b    s              h   a            s    s
+//                                                   l     w   d   b     s              h   a            s    s                               e    h    b    t    w    l
-//                                                    e     i   e   o    c              u   x            c    c
+//                                                   e     i   e   o     c              u   x            c    c                               x    u    a    o    a    u
-//                                                    n     d   p   r    r              b   i            r    r
+//                                                   n     d   p   r     r              b   i            r    r                               i    b    s    p    l    g
-//                                                    g     t   t   e    e                  s            e    w
+//                                                   g     t   t   e     e                  s            e    e                               t         e         l
-//                                                    t     h   h        w              d                w    w
+//                                                   t     h   h         w              d                w    w                                              t
-//                                                    h                                                  h    s
+//                                                   h                                                  h    s                                         t         t
 RB5015 = ["RB5015", "Blower Runda RB5015",           51.3, 51, 15, 31.5, M4_cap_screw, 26, [27.3, 25.4], 4.5, [[4.3, 45.4], [47.3,7.4]],     20,   14,  1.5, 1.3, 1.2, 15];
 PE4020 = ["PE4020", "Blower Pengda Technology 4020", 40,   40, 20, 27.5, M3_cap_screw, 22, [21.5, 20  ], 3.2, [[37,3],[3,37],[37,37]],       29.3, 17,  1.7, 1.2, 1.3, 13];
-BL40x10 =["R4010", "Square radial 4010",             40,   40,9.5, 27,   M2_cap_screw, 16, [24,   20  ], 2.4, [[2,2,1.5],[38,2,1.5],[2,38,1.5],[38,38,1.5]], 28, 9.5, 1.5, 1.5, 1.3,  0];
+BL40x10 =["BL40x10","Square radial 4010",            40,   40,9.5, 27,   M2_cap_screw, 16, [24,   20  ], 2.4, [[2,2],[38,2],[2,38],[38,38]], 30  , 9.5, 1.5, 1.5, 1.1, 1.5];
 
 blowers = [BL40x10, PE4020, RB5015];