Anti-spin dust seal for cone and gyratory crushers

1. A dust seal for a cone crusher or gyratory crusher, the crusher including a stationary part comprising a dust collar, and a crusher head which is supported so as to be rotatable relative to the stationary part in a crushing direction of rotation and in an idling direction of rotation which is opposite to the crushing direction of rotation, the dust seal comprising:

a crusher head contact portion configured for directly or indirectly contacting the crusher head, and a dust collar contact portion configured for directly or indirectly contacting the dust collar, and

the dust seal being configured to impart a frictional force between the crusher head and the dust seal via the crusher head contact portion, and/or a frictional force between the dust collar and the dust seal via the dust collar contact portion upon rotation of the crusher head at least in the idling direction of rotation,

wherein the dust seal is configured so that the frictional force imparted by the dust collar contact portion and/or the crusher head contact portion is higher upon rotation of the crusher head in the idling direction of rotation than upon rotation of the crusher head in the crushing direction of rotation.

2. The dust seal of claim 1 , in which the stationary part includes a stationary frame and the dust collar mounted to the stationary frame, wherein the dust seal is configured so as to be in sealing contact with the dust collar and/or the crusher head upon mounting the dust seal to the crusher.

3. The dust seal of claim 1 , comprising a plurality of protrusions arranged on the dust collar contact portion for sealingly contacting the dust collar and/or on the crusher head contact portion for sealingly contacting the crusher head, and protruding from a base of the dust collar.

4. The dust seal of claim 3 , wherein at least one of the protrusions is configured such that a frictional force imparted between the at least one protrusion and the dust collar at the dust collar contact portion and/or the crusher head at the crusher head contact portion upon rotation of the crusher head is higher in the idling direction of rotation than in the crushing direction of rotation.

5. The dust seal of claim 3 , wherein the dust seal is a ring-shaped dust seal and at least one of the protrusions is more deformable in a first tangential direction of the ring-shaped dust seal upon rotation of the head in the crushing direction of rotation, than in a second tangential direction of the ring-shaped dust seal upon rotation of the crusher head in the idling direction of rotation, which is opposite to the first tangential direction of the ring-shaped dust seal upon rotation of the head in the crushing direction of rotation.

6. The dust seal of claim 3 , wherein the dust seal is a ring-shaped dust seal and at least one of the protrusions is inclined relative to a radial direction of the ring-shaped dust seal towards a tangential direction upon rotation of the head in the idling direction of rotation so as to impart the higher frictional force in the idling direction of rotation.

7. The dust seal of claim 3 , wherein at least one of the protrusions has a substantially triangular shape, viewed in a plane parallel to a horizontal plane defined by the dust seal.

8. The dust seal of claim 3 , wherein at least one of the protrusions is at least 2 mm thick in a radial direction of the dust seal.

9. The dust seal of claim 3 , wherein at least one of the protrusions protrudes for at least 5 mm from the base.

10. The dust seal of claim 3 , wherein the protrusions comprise a resilient material.

11. The dust seal of claim 3 , wherein at least 30 protrusions are provided.

12. The dust seal of claim 1 , wherein the crusher head contact portion further comprises a friction lip for sealingly contacting the crusher head.

13. The dust seal of claim 1 , further comprising a holder to which the dust collar contact portion and/or the crusher head contact portion are mounted.

14. The dust seal of claim 13 , further comprising a form part accommodating the holder in a form-fitting manner.

15. A cone or gyratory crusher, the crusher comprising:

a stationary part comprising a dust collar, and a crusher head which is supported so as to be rotatable relative to the stationary part in a crushing direction of rotation and in an idling direction of rotation which is opposite to the crushing direction of rotation, and a dust seal including a crusher head contact portion configured for directly or indirectly contacting the crusher head, and a dust collar contact portion configured for directly or indirectly contacting the dust collar;

wherein the dust seal is configured to impart a frictional force between the crusher head and the dust seal via the crusher head contact portion, and/or a frictional force between the dust collar and the dust seal via the dust collar contact portion upon rotation of the crusher head at least in the idling direction of rotation;

wherein the dust seal is configured so that the frictional force imparted by the dust collar contact portion and/or the crusher head contact portion is higher upon rotation of the crusher head in the idling direction of rotation than upon rotation of the crusher head in the crushing direction of rotation; and

wherein the dust seal being provided between the crusher head and the dust collar so as to provide a sealing to prevent the entrance of rock dust into an operating mechanism of the crusher.

16. The crusher according to claim 15 , further comprising a rotatable eccentric to which the crusher head is journalled,

wherein the dust seal is configured such that the frictional force imparted between the crusher head and the dust collar upon rotation of the head in the idling direction of rotation exceeds the frictional force imparted between the head and the eccentric upon rotation of the eccentric in the idling direction of rotation, preventing the head from being rotationally dragged by the eccentric in the idling direction of rotation.

17. The crusher according to claim 15 , the dust collar being configured to increase the frictional force between the dust collar and the dust collar contact portion upon rotation of the crusher head in the idling direction of rotation, the dust collar having a recesses configured to receive protrusions of the dust collar contact portion.

18. The dust seal according to claim 1 , wherein the dust seal is ring-shaped.