Cone crusher having positive head hold-down mechanism

A gyratory crusher for crushing material, comprising:

• (a) a lower frame;
• (b) an upper frame supported by the lower frame and having a bonnet secured thereto, the bonnet having an upper opening for receiving the material;
• (c) an eccentric member rotatably mounted to the lower frame;
• (d) a crusher head having a main shaft rotatably mounted to the eccentric member, the crusher head and the bonnet forming a crushing chamber therebetween, the main shaft having an upper end and a lower end;
• (e) a drive motor for rotating the eccentric member;
• and
• (f) a hold down assembly coupled to the lower end of the main shaft arid engaging the eccentric member, the hold down assembly being adapted to limit axial movement of the main shaft relative to the eccentric member.

A gyratory crusher for crushing material, comprising:

• (a) a frame;
• (b) a bonnet;
• (c) a gyrating crusher head having a main shaft supported by the frame for relative gyrational movement, the crusher head and the bonnet forming a crushing chamber therebetween, the main shaft having an upper end and a lower end;
• (d) a drive motor for gyrating the crusher head;
• and
• (e) a hold down mechanism operatively connecting the lower end of the main shaft to the frame to prevent axial movement of the main shaft relative to the frame.

A device for preventing levitation of a crusher head on a gyratory crusher, the gyratory crusher having a frame, a bonnet, and a main shaft supporting the crusher head, a lower end of the main shaft being received in an eccentric member, the device comprising:

• a bore extending axially through the main shaft and having a lower end;
• a draw rod secured to the crusher head and having a lower end extending to the main shaft lower end;
• a sleeve engaging the draw rod lower end;
• and
• a retaining member engaging the sleeve and being operatively connected to the eccentric member;
• whereby the draw rod, the sleeve, and the retaining member cooperate to prevent undesired vertical movement of the main shaft relative to the frame.