MOVABLE-JAW CRUSHER AND CRUSHING MACHINE OF RUBBLE AND SIMILAR PROVIDED WITH SUCH CRUSHER

TECHNICAL FIELD The present invention relates to a movable-jaw crusher and to a crushing machine of rubble and similar provided with such crusher.

More specifically, the present invention relates to a movable-jaw crusher and to a crushing machine of rubble and similar of the self-propelled type, to which the following description refers purely by way of example without loosing in generality. BACKGROUND ART

It is known that most crushing machines of rubble, rock, quarry material, building and road demolition waste and similar essentially consist of a movable-jaw crusher capable of crushing the above-mentioned material by exploiting the mechanical action of a pair of movable jaws, and of a vibrating feeder capable of conveying the material to be crushed into the crusher, both positioned over a load-bearing frame provided with tracks resting on the ground.

More specifically, movable-jaw crushers are capable of crushing the above-mentioned material by exploiting the mechanical action of a pair of jaws which are positioned facing each other to define the two sloping side walls of a downward-converging hopper, and are

cyclically moved towards each other to crush the material trapped between the jaws, i.e. the material inside the hopper. Instead, the vibrating feeder is capable of conveying the material to be crushed towards the inlet mouth of the hopper by exploiting the action of a movable loading surface which has a side edge arranged immediately over the inlet mouth of the hopper, slopes by a few degrees towards the inlet mouth of the hopper and it is finally subjected to continuous shaking with component parallel to the laying plane of the loading surface by a hydraulically-operated vibrating assembly, so as to make the material to be crushed slowly go towards the side edge over the inlet mouth of the hopper. In most cases, crushing machines of rubble and similar are further provided with a vibrating sieve which is arranged on the load-bearing structure, immediately downstream of the vibrating feeder, so as to intercept the smaller sized part of the material to be crushed directed towards the movable-jaw crusher, and which does not thus need to pass through the crusher.

Regretfully, it is known that this type of crushing machine has the tendency of being flooded when the material which is poured into the vibrating feeder is very heterogeneous and is not fed with sufficient gradualness. In these cases, in fact, it often occurs that the material to be crushed tends to temporarily

accumulate on the vibrating loading bed of the vibrating feeder and then it suddenly pours into the hopper formed by the two movable jaws, causing the immediate jamming of the movable-jaw crusher due to excess of working load with all the drawbacks that this implies .

DISCLOSURE OF INVENTION

It is the object of the present invention to make a crushing machine of rubble and similar of the self- propelled type which is free from the above-described drawbacks .

According to the present invention, there is thus provided a movable-jaw crusher as described in claim 1 and preferably, but not necessarily, in any of the subsequent claims, depending either directly or indirectly from claim 1.

According to the present invention, there is further provided a crushing machine of rubble and similar as described in claim 6 and preferably, but not necessarily, in any of the subsequent claims, depending either directly or indirectly from claim 6.

BRIEF DESCRIPTION OF THE DRAWINGS

A non-limiting embodiment of the present invention will now be described by way of example with reference to the accompanying drawings, in which: - figure 1 is a side view of a crushing machine of rubble and similar in accordance with the teachings of the present invention, with parts in section and parts

removed for clarity; figure 2 is a side view of the movable-jaw crusher mounted on ^' the .machine shown in figure 1, with parts in section and parts removed for clarity. BEST MODE TO CARRYING OUT THE INVENTION

With reference to figure 1, number 1 indicates as a whole a crushing machine of rubble and similar which is particularly suitable for crushing rubble, rock, quarry material, building and road demolition waste and similar material.

Crushing machine 1 essentially comprises a load- bearing structure 2, preferably, but not necessarily, provided with a pair of tracks resting on the ground, and the corresponding actuating members (not shown) ; a movable-jaw crusher 3 which is capable of receiving a continuous input flow of heterogeneous material to be crushed, and of providing a continuous output flow of crushed material having a predetermined and uniform size whose value depends on the configuration of crusher 3 during the crushing of the above-mentioned material; and finally a vibrating feeder 4 which is capable of receiving a discontinuous input flow of material to be crushed and of conveying an essentially constant input flow of the aforesaid material to crusher 3. Crusher 3 and vibrating feeder 4 are obviously positioned side-by-side on load-bearing structure 2, aligned along the main axis of load-bearing structure 2

itself, and crushing machine 1 is further provided with a belt conveyor 5 or similar which is capable of receiving the crushed material outgoing from crusher 3 and transporting it outside crushing machine 1. Preferably, but not necessarily, machine 1 is finally provided with a vibrating sieve 6 which is arranged on load-bearing structure 2, between crusher 3 and vibrating element 4, so as to be able to intercept and deviate . towards other destination the smaller sized part of the material to be crushed which is directed towards crusher 3, and which thus does not need to pass through crusher 3.

With particular reference to figure 2, movable-jaw crusher 3 is essentially formed by an external casing or machine body 7, in which is obtained a crushing compartment or chamber 8 which is provided with a top opening 8a through which the material to be crushed is fed, and a bottom opening 8b through which the crushed material comes out; by a pair of crushing jaws 9 and 10 positioned inside crushing chamber 8 facing each other so as to define the two sloping side walls of a downward-converging hopper; and by a jaw actuating device 11 which is capable of cyclically moving the two crushing jaws 9 and 10 against each other to crush the material trapped between the jaws themselves, i.e. inside the hopper.

More specifically, in the example shown crushing

chamber 8 is laterally defined by two vertical side walls 12 which _. extend parallel to and facing each other, whereas each of the two crushing jaws 9 and 10 comprises a flat front plate 13 formed by high strength metal which extends parallelly to the two vertical side walls 12, and a rear supporting structure 14 which, depending on the type of jaw, is either rigidly fixed to casing 2 of the machine or is connected in floating manner to casing 7 itself by means of actuating device 11. In the case in point, crushing jaw 9 has a rear supporting structure 14 rigidly fixed to casing 7 of the crusher thus defining the "fixed jaw" of the machine, while rear supporting structure 14 of crushing jaw 10 is cantilevered inside casing 7 on the eccentric segment of a supporting shaft 15 which is capable of freely rotating about a horizontal rotation axis A perpendicular to the two vertical side walls 12 of casing 7, and thus defines the "movable jaw" of the machine . More specifically, the eccentric segment of supporting shaft 15 is freely rotationally inserted in a through hole which extends in the top part of rear supporting structure 14 of crushing jaw 10 coaxially to a horizontal axis parallel to axis A, so that the rotation of supporting shaft 15 about axis A makes the entire crushing jaw 10 oscillate.

With reference to figure 2, in addition to

supporting shaft 15, actuating device 11 further comprises a motor flywheel 16 which is rigidly keyed onto an end of supporting shaft 15 coaxial to axis A so as to rotate about said axis A along with the shaft, and a motor, either electric, hydraulic or similar (not shown) which is able to rotationally drive motor flywheel 16 and supporting shaft 15 connected to it about aforesaid axis A.

Additionally, actuating device 11 finally comprises a collapsible connecting member 17 which is adapted to connect rear supporting structure 14 of crushing jaw 10, i.e. the movable jaw, in floating manner to casing 7 of the crusher to allow crushing jaw 10 to freely oscillate about a horizontal reference axis under the bias of supporting shaft 15, concurrently allowing minor displacements in the horizontal and vertical sense.

Specifically, in the example shown, collapsible connection member 17 comprises an oscillating connecting rod 18 which is hinged and cantilevered on casing 7 of the crusher so as to be able to freely oscillate about a horizontal axis B parallel to axis A; a reaction strut 19 which has a first end abutting on the rear part of rear supporting structure 14 of crushing jaw 10 and a second end abutting on the free end of oscillating connecting rod 18, in turn arranged in essentially vertical position; and finally at least one hydraulic thrust-bearing cylinder 20 interposed between the free

end of oscillating connecting rod 18 and casing 7 of the crusher, on the opposite side of strut 19.

More specifically, in the example shown, strut 19 consists of a flat metal plate of essentially rectangular shape which extends perpendicularly to the two vertical side walls 12 of casing 7 of the crusher, and has two longer side edges abuttingly arranged one on the free end of oscillating connecting rod 18, and the other on rear supporting structure 14 of crushing jaw 10, while collapsible connecting member 17 is provided with twin hydraulic thrust-bearing cylinders 20 which are arranged side-by-side on opposite sides of the vertical middle plane of the machine - plane which is perpendicular to rotation axis A of supporting shaft 15 and parallel to the plane of the sheet in figure 1 -, and are both arranged between the free end of oscillating connecting rod 18 and a horizontal stiffening crossbar 21, the function of which is to rigidly and reciprocally connect the two vertical side walls 12 of casing 7 of the crusher.

Oscillating connecting rod 18, strut 19 and the two hydraulic thrust-bearing cylinders 20 are components already widely known in the field and therefore no further description is required, except for specifying that in the example shown the two ends of each hydraulic thrust-bearing cylinder 20 are abuttingly arranged one against the free end of oscillating connecting rod 18,

and the other against horizontal stiffening crossbar 21 by means of ball joints of - known type; and that collapsible connecting member 17 also comprises an auxiliary single- or dual-acting hydraulic cylinder 22 which has its two ends hinged one onto horizontal stiffening crossbar 21 and the other onto the free end of oscillating connecting rod 18, and is connected to the machine hydraulic circuit (not shown) to exert a mechanical traction force on horizontal stiffening crossbar 21 and on the free end of oscillating connecting rod 18, which force tends to constantly maintain oscillating connecting rod 18 abutting against the movable shafts of the two hydraulic thrust-bearing cylinders 20, and the bottom of the two hydraulic thrust-bearing cylinders 20 abutting against horizontal stiffening crossbar 21.

As regards instead vibrating feeder 4 and vibrating sieve 6, with reference to figure 1, vibrating sieve 6 essentially consists of a movable grid 24 of preferably, but not necessary, rectangular shape which is elastically connected to load-bearing structure 2 of the machine by means of coil springs and/or other elastic elements of known type; of an electrically- or hydraulicalIy-operated vibrating member 25 which is mechanically connected to movable grid 24 to shake it on command along a directrix essentially perpendicular to the laying plane of the grid itself, at an adjustable

frequency so as to cause, the progressive advancement of the material towards an output edge of the grid itself; and finally of an unloading hopper 26 which is positioned immediately underneath movable grid 24 so as

'5 to collect the small-sized material to be crushed which crosses movable grid 24.

More specifically, movable grid 24 is positioned by the side of crusher 3 with a side edge arranged immediately over top opening 8a of the hopper formed by 0 crushing jaws 9 and 10, and is sloped by a few degrees towards top opening 8a so that the larger sized material to be crushed slides by gravity directly towards crusher 3.

With reference to figure 1, vibrating feeder 4 5 instead comprises a movable loading surface 27 elastically suspended onto load-bearing structure 2 of the machine, an electrically- or hydraulically- operated vibrating member 28 which is mechanically connected to loading surface 27 to make it vibrate on command and 0 cause the progressive advancement of the material towards an output edge of the surface itself, and finally a containment side rail 29 which surrounds loading surface 27 so as to avoid the accidental dropping of material to be crushed outside the surface 5 itself.

More specifically, loading surface 27 has a preferably, but not necessarily, rectangular shape, is

elastically connected to load-bearing structure 2 of the machine by means of coil springs and/or' other elastic element of known type, and is arranged in essentially horizontal position by the side of vibrating sieve 6, on the opposite side of crusher 3, so that its side edge overhangingly protrudes immediately over movable grid 24 of vibrating sieve 6. .

Electrically- or hydraulicalIy-operated vibrating member 28 is instead structured so as to be able to shake loading surface 27, on command and at an adjustable frequency, along a directrix sloping towards the side edge over movable grid 24 of vibrating sieve 6 so as to make the material to be crushed slowly advance towards the side edge over vibrating sieve 6. With reference to figures 1 and 2, movable-jaw crusher 3 is finally provided with at least one ultrasound proximity sensor 30 which is positioned immediately over top opening 8a of the hopper formed by crushing jaws 9 and 10, and is capable of outputting an electric signal indicating the average distance d existing between the sensor itself and the surface of the mass of material to be crushed present inside the hopper formed by crushing jaws 9 and 10, and by an electronic control unit 31 which is connected to proximity sensor 30, is capable of instantaneously determining the level of the material to be crushed present inside the hopper formed by the crushing jaws 9

and 10, and is finally capable of driving vibrating member 28 of vibrating feeder 4 and/or vibrating member 25 of vibrating sieve- 6 so as to keep the level of material to be crushed inside the ^' hopper of crusher 3 around an optimal predetermined value.

More -specifically, _ electronic control unit 31 is finally capable of driving vibrating member 28 of vibrating feeder 4 and/or vibrating member 25 of vibrating sieve 6, so as to vary the frequency of the vibrations instantaneously transmitted to loading surface 27 and/or movable grid 24, so as to adjust the speed at which the material to be crushed is displaced towards crusher 3 according to the filling level of crusher 3. In the ^' case in point, electronic control unit 31 increases the speed at which vibrating feeder 4 and/or vibrating sieve 6 advance the material to be crushed towards crusher 3 if the level of material in crusher 3 falls under the aforesaid optimal value, and either reduces or takes to zero the speed at which vibrating feeder 4 and/or vibrating sieve 6 advance the material to be crushed towards crusher 3 if the material inside crusher 3 increases over the same aforesaid optimal value. Operation of rubble and similar crushing machine 1 and of crusher 3 are easily deducible from the foregoing description and therefore no further explanation is

required, except for specifying that ultrasound proximity sensor 30 is capable of measuring the distance •d of the material to be crushed without- being affected by dust, mud and dirt which may be accidentally released from crushing chamber 18 of crusher 3, and thus electronic control unit 31 is capable of always determining the exact level of ^' the material to be crushed inside the hopper formed by crushing jaws 9 and 10. The advantages of crushing machine 1 are evident: in virtue of the feedback control of the advancement speed of the material to be crushed towards crusher 3

^' according to the filling level of crusher 3 itself,

^■ electronic control unit 31 is capable of constantly operating crushing machine 1 in conditions of maximum efficiency, with all the advantages that this implies in terms of productivity and durability of the machine in time.

It is finally apparent that changes and variants ' can be made to crushing machine 1 described and illustrated herein without departing from the scope of protection of the present invention.

For example, with reference to figure 2, crusher 3 may further be provided with a pressure sensor 32 which is adapted to instantaneously detect the pressure value of the oil contained inside the variable-volume chamber of hydraulic thrust-bearing cylinder 20, which variable-

volume chamber is intended to reduce its volume when the movable shaft of hydraulic thrust-bearing cylinder 20 retracts into the external tubular casing of the cylinder itself. In this case, electronic control unit 31. is capable of adjusting the speed at which vibrating feeder 4 and/or vibrating sieve 6 feed the material to be crushed towards crusher 3 both according to the level of the material contained in the hopper formed by crushing jaws 9 and 10, and according to the pressure of the oil present in the variable-volume chamber on bottom side of hydraulic thrust-bearing cylinder 20 so as to directly control also the mechanical stresses which are relieved onto the entire structure of crusher 3.