Add bolts on rotor

nhf/touhou/yasaka_kanako/onbashira.py

@@ -25,13 +25,17 @@ class Onbashira(Model):
     # Size of ball bearings
     bearing_ball_diam: float = 25.4 * 1/2
     bearing_ball_gap: float = .5
-    bearing_height: float = 40.0
+    # Thickness of bearing disks
     bearing_thickness: float = 20.0
     bearing_track_radius: float = 120.0
     # Gap between the inner and outer bearing disks
     bearing_gap: float = 10.0
     bearing_disk_thickness: float = 25.4 / 8
 
+    rotor_bind_bolt_diam: float = 10.0
+    rotor_bind_radius: float = 50.0
+    stator_bind_radius: float = 150.0
+
     material_side: Material = Material.WOOD_BIRCH
     material_bearing: Material = Material.PLASTIC_PLA
     material_bearing_ball: Material = Material.ACRYLIC_TRANSPARENT
@@ -41,8 +45,9 @@ class Onbashira(Model):
         assert self.n_side >= 3
         # Bulk must be large enough for the barrel + bearing to rotate
         assert self.bulk_radius - self.side_thickness - self.bearing_thickness - self.bearing_diam > self.rotation_radius + self.barrel_diam / 2
-        assert self.bearing_height > self.bearing_diam
         assert self.bearing_gap < 0.95 * self.bearing_ball_diam
+        assert self.rotor_bind_bolt_diam < self.rotor_bind_radius < self.bearing_track_radius
+        assert self.bearing_track_radius < self.stator_bind_radius
 
     @property
     def angle_side(self) -> float:
@@ -62,6 +67,9 @@ class Onbashira(Model):
 
     @property
     def bearing_disk_gap(self) -> float:
+        """
+        Gap between two bearing disks to touch the bearing balls
+        """
         diag = self.bearing_ball_diam
         dx = self.bearing_gap
         return math.sqrt(diag ** 2 - dx ** 2)
@@ -72,6 +80,12 @@ class Onbashira(Model):
             Cq.Sketch()
             .regularPolygon(self.side_width, self.n_side)
             .circle(self.bearing_track_radius + self.bearing_gap/2, mode="s")
+            .reset()
+            .regularPolygon(
+                self.stator_bind_radius, self.n_side,
+                mode="c", tag="bolt")
+            .vertices(tag="bolt")
+            .circle(self.rotor_bind_bolt_diam/2, mode="s")
         )
     def bearing_stator(self) -> Cq.Workplane:
         return (
@@ -81,12 +95,22 @@ class Onbashira(Model):
         )
     @target(name="bearing-rotor", kind=TargetKind.DXF)
     def profile_bearing_rotor(self) -> Cq.Sketch:
+        bolt_angle = 180 / self.n_side
         return (
             Cq.Sketch()
             .circle(self.bearing_track_radius - self.bearing_gap/2)
-            .regularPolygon(self.rotation_radius, self.n_side)
+            .reset()
-            .vertices()
+            .regularPolygon(
+                self.rotation_radius, self.n_side,
+                mode="c", tag="corners")
+            .vertices(tag="corners")
             .circle(self.barrel_diam/2, mode="s")
+            .reset()
+            .regularPolygon(
+                self.rotor_bind_radius, self.n_side,
+                mode="c", tag="bolt", angle=bolt_angle)
+            .vertices(tag="bolt")
+            .circle(self.rotor_bind_bolt_diam/2, mode="s")
         )
     def bearing_rotor(self) -> Cq.Workplane:
         return (
@@ -96,7 +120,25 @@ class Onbashira(Model):
         )
     @target(name="bearing-gasket", kind=TargetKind.DXF)
     def profile_bearing_gasket(self) -> Cq.Sketch:
-        pass
+        dr = self.bearing_ball_diam
+        eps = 0.05
+        return (
+            Cq.Sketch()
+            .circle(self.bearing_track_radius + dr)
+            .circle(self.bearing_track_radius - dr, mode="s")
+            .reset()
+            .regularPolygon(
+                self.bearing_track_radius, self.n_bearing_balls,
+                mode="c", tag="corners")
+            .vertices(tag="corners")
+            .circle(self.bearing_ball_diam/2 * (1+eps), mode="s")
+        )
+    def bearing_gasket(self) -> Cq.Workplane:
+        return (
+            Cq.Workplane()
+            .placeSketch(self.profile_bearing_gasket())
+            .extrude(self.bearing_disk_thickness)
+        )
 
 
     @target(name="pipe", kind=TargetKind.DXF)
@@ -138,7 +180,7 @@ class Onbashira(Model):
         return Cq.Solid.makeSphere(radius=self.bearing_ball_diam/2, angleDegrees1=-90)
 
     def assembly_rotor(self) -> Cq.Assembly:
-        z_lower = -self.bearing_disk_gap - self.bearing_disk_thickness
+        z_lower = -self.bearing_disk_gap/2 - self.bearing_disk_thickness
         a = (
             Cq.Assembly()
             .addS(
@@ -169,6 +211,13 @@ class Onbashira(Model):
                 role=Role.ROTOR,
                 loc=Cq.Location(0, 0, z_lower)
             )
+            .addS(
+                self.bearing_gasket(),
+                name="gasket",
+                material=self.material_bearing,
+                role=Role.ROTOR,
+                loc=Cq.Location(0, 0, -self.bearing_disk_thickness/2)
+            )
         )
         for i in range(self.n_bearing_balls):
             ball = self.bearing_ball()
@@ -186,7 +235,7 @@ class Onbashira(Model):
         a = Cq.Assembly()
         side = self.side_panel()
         r = self.bulk_radius
-        a = a.add(self.assembly_bearing(), name="bearing")
+        a = a.add(self.assembly_rotor(), name="rotor")
         for i in range(self.n_side):
             a = a.addS(
                 side,