Cone crusher with lubricating means

Abstract

 A cone crusher comprising a mantle fixed to and rotatable with a head shaft about which an eccentric weight or unbalanced mass is relatively rotatable, the head shaft and eccentric being commonly driven by a friction drive which permits a degree of angular movement of the rotational axis of the head shaft relative to the rotational axis of the friction drive. In accordance with the invention means is provided for supplying a lubricating fluid under pressure from the friction drive to the interior of the head shaft, the head shaft having at least one radial bore which communicates its interior with the peripheral surface of the head shaft at a position where the shaft is surrounded by the eccentric.

Description

[0001] This invention relates to an improved cone crusher, by which is meant a machine which crushes or pulverises rock or other particulate solids to reduce the particle size. Crushing is effected between a rotating conical head or mantle and a fixed conical shroud, the rotating mantle being influenced by a rotating, off-centre weight or flywheel which imparts an oscillating movement to the mantle which alters the gap between the mantle and the shroud.

[0002] Cone crushers of this kind have been well known for many years but have a short working life because of the enormous frictional forces to which their components are subjected. In particular the bearing between the shaft on which the mantle is mounted and the off-centre flywheel rapidly bums out because the flywheel rotates faster than the shaft when the mantle is decelerated by a workload and at the same time the oscillation generated by the flywheel is applied to the shaft over this bearing. Other problems associated with known cone crushers include the ingress of dust and small particles of the material being crushed through bearings of the mantle or its seating leading to failure of the bearings. In view of the high cost of this apparatus it is highly desirable that its working life should be extended.

[0003] A principal object of the present invention is to address the problems associated with known cone crushers.

[0004] In accordance with one aspect of the present invention there is provided a cone crusher comprising a mantle fixed to and rotatable with a head shaft about which an eccentric weight or unbalanced mass is relatively rotatable, the head shaft and eccentric being commonly driven by a friction drive which permits a degree of angular movement of the rotational axis of the head shaft relative to the rotational axis of the friction drive, wherein means is provided for supplying a lubricating fluid under pressure from the friction drive to the interior of the head shaft, the head shaft having at least one radial bore which communicates its interior with the peripheral surface of the head shaft at a position where the shaft is surrounded by the eccentric.

[0005] Preferably said radial bore opens to the peripheral surface of the shaft at a position intermediate the axial end surfaces of the eccentric.

[0006] Preferably the friction drive comprises a drive shaft and a universal coupling interposed between the drive shaft on the one hand and the head shaft and eccentric on the other hand, the drive shaft having drillings whereby oil under pressure is admitted to an axial bore through the universal coupling whereby oil is conveyed to the interior of the head shaft.

[0007] In accordance with another aspect of the present invention there is provided a cone crusher comprising a head fixed to and rotatable with a shaft about which an eccentric flywheel is relatively rotatable, the shaft and flywheel being commonly driven by a friction drive which permits a degree of angular movement of the rotational axes of the shaft and flywheel relative to the rotational axis of the friction drive, wherein an annular seal is provided between an annular undersurface of the head and a mainframe of the cone crusher, the seal comprising an oil-impregnated plastics material which is spring urged into contact with the mantle whereby contact of the seal with the mantle is not lost due to oscillation of the head relative to the mainframe and whereby wear of the seal is compensated by the spring means.

[0008] Preferably the head has an inwardly and downwardly directed underskirt which is contacted by a similarly inclined surface of the seal, the seal being under the influence of circumferentially distributed compression springs located in respective blind bores in the mainframe.

[0009] A preferred embodiment of the present invention will now be described by way of non-limitative example with reference to the accompanying drawings, in which:

Figure 1 is a sectional elevation of a cone crusher in accordance with the present invention, and

Figure 2 is a detail on an enlarged scale of the cone crusher of Figure 1.

[0010] The cone crusher illustrated has a main frame 10 in which a drive shaft 21 is rotatable by a pulley 22 driven by an electric motor (not shown). A support shaft 18 provides a universal coupling between the drive shaft 21 and a tubular shaft 11 on which is mounted an eccentric weight or unbalanced mass 13. Within the tubular shaft 11 is mounted a head shaft 28, also friction driven by the support shaft 18 but rotatable relative to the tubular shaft 11. Fixed to the top of the head shaft 28 is a generally conical head 27 the underside of which is machined to a spherical radius and seated on a spherical bearing 110. The spherical bearing 110 is supported by a socket 29 which is in turn bolted to the main frame 10.

[0011] Overlying the head 27 is a frusto conical mantle liner 9. Confronting this over an adjustable gap is a concave liner 8 fixed relative to the frame 10 and at the centre of which is the outlet of a hopper 111 whereby material to be crushed is introduced between the liners 8 and 9. It will be noted that the gap between these liners tapers downwardly so that material being crushed is subjected to progressively increasing crushing forces as it passes downwardly under gravity.

[0012] In use rotation of the drive shaft 21 causes rotation of the head shaft 28 and eccentric 13, the latter imparting an oscillating motion to the rotating mantle liner 9. As material is crushed between the liners 8 and 9 it will tend to retard rotation of the head shaft 27 so that the eccentric 13 will rotate faster than the head shaft.

[0013] Lubricating oil under pressure is introduced at two points 30 and 31. Oil entering the inlet 30 passes through the socket 29 and spherical bearing 110, emerging between the opposed surfaces of the bearing 110 and the head 27. Oil falling from the radially inner and radially outer ends of the spherical bearing 110 falls through the frame 10 to exit through a drain hole 32.

[0014] Oil entering the inlet 31 passes to an annular chamber 33 communicating with drillings 34 in the drive shaft 21. The shaft coupling 18 has a coaxial bore 35 through which oil from the drillings 34 passes to a chamber 36 in the bottom of the head shaft 28 above an upper bearing 37 of the shaft coupling. From thence the oil passes through a coaxial blind bore 38 in the head shaft 28 and through a radial bore 39, emerging between the head shaft 28 and the tubular shaft 11 intermediate the axial ends of the latter. Oil thus lubricating the bearing between the head shaft 28 and the eccentric weight or unbalanced mass 13 may emerge from the top of the tubular shaft 11, where it will fall through the frame 10 to exit through the outlet 32.

[0015] Both the upper and lower bearings of the shaft coupling 18 are also lubricated by oil from the inlet 31. The lower bearing 40 of the shaft coupling 18 is cup-shaped with an annular flange 41 which acts on a thrust bearing 42. Oil from the chamber 33 can also pass upwardly around the outside of the cup-shaped bearing 40, emerging at the top of a bush 43 to fall through the frame 10 to the outlet 32.

[0016] Oil also passes downwardly from the chamber 33 to lubricate the drive shaft 21. An annular recess 50 in the underside of the drive shaft 21 communicates with a cross drilling 51 which in turn communicates with a rotary coupling 52 , the inlet end of which extends through the bearing of the pulley 22. Oil discharged from the drive shaft 21 exits through the rotary coupling 52, which is connected to the same reservoir tank (not shown) as the outlet 32 of the frame.

[0017] Figure 2 shows part of the head 27 on a larger scale. Near to its periphery the head 27 is formed with an inwardly and downwardly directed underskirt 44 which, as the head rotates and oscillates, is in rubbing contact with a similarly inclined surface of an annular seal 45 of an oil-impregnated plastics material. The seal 45 is under the influence of a series of compression springs circumferentially distributed around the frame 10, one of which is indicated at 46. The springs act on the seal 45 through respective hollow plungers 47, which serve to maintain the seal 45 in contact with the skirt 44 irrespective of angular movement of the head 27 and also compensate for wear of the seal.

Claims

1. A cone crusher comprising a mantle fixed to and rotatable with a head shaft about which an eccentric weight or unbalanced mass is relatively rotatable, the head shaft and eccentric being commonly driven by a friction drive which permits a degree of angular movement of the rotational axis of the head shaft relative to the rotational axis of the friction drive, characterised in that means is provided for supplying a lubricating fluid under pressure from the friction drive to the interior of the head shaft, the head shaft having at least one radial bore which communicates its interior with the peripheral surface of the head shaft at a position where the shaft is surrounded by the eccentric.

2. A cone crusher as claimed in claim 1, characterised in that said radial bore opens to the peripheral surface of the shaft at a position intermediate the axial end surfaces of the eccentric.

3. A cone crusher as claimed in either preceding claim, characterised in that the friction drive comprises a drive shaft and a universal coupling interposed between the drive shaft on the one hand and the head shaft and eccentric on the other hand, the drive shaft having drillings whereby oil under pressure is admitted to an axial bore through the universal coupling whereby oil is conveyed to the interior of the head shaft.

4. A cone crusher comprising a head fixed to and rotatable with a shaft about which an eccentric flywheel is relatively rotatable, the shaft and flywheel being commonly driven by a friction drive which permits a degree of angular movement of the rotational axes of the shaft and flywheel relative to the rotational axis of the friction drive, characterised in that an annular seal is provided between an annular undersurface of the head and a mainframe of the cone crusher, the seal comprising an oil-impregnated plastics material which is spring urged into contact with the mantle whereby contact of the seal with the mantle is not lost due to oscillation of the head relative to the mainframe and whereby wear of the seal is compensated by the spring means.

5. A cone crusher as claimed in claim 4, characterised in that the head has an inwardly and downwardly directed underskirt which is contacted by a similarly inclined surface of the seal, the seal being under the influence of circumferentially distributed compression springs located in respective blind bores in the mainframe.

Drawing