The invention relates to a jaw crusher for a rubble crushing device, comprising a grab bucket provided with an inlet opening for rubble parts to be reduced in size, an outlet opening for reduced rubble parts, at least two co-acting crushing bodies for reducing rubble parts in size therebetween, and drive means for moving one of the at least two crushing bodies relative to the other crushing body, which drive means comprise one flywheel and at least one motor.

Known from European patent application publication number EP-1138834-A2 is a jaw crusher which is intended for attachment to a movable arm of a self-propelled vehicle. The known jaw crusher comprises two co-acting crushing bodies formed by a fixed wall and a crushing plate oscillating thereabove which is driven by an eccentric on a shaft, this shaft being set into rotation by a hydraulic motor. The rotation speed of the shaft, and thereby the continuity of the oscillating movement of the crushing plate, is held constant using two flywheels suspended from the ends of the shaft close to the side walls of the bucket of the jaw crusher.

It is a drawback of the known jaw crusher that, due to the two flywheels, it is very heavy. Too great a weight makes the jaw crusher unsuitable for mounting on the boom of for instance an excavator or a wheel loader, and therefore unsuitable as jaw crusher for a mobile rubble crushing device. Owing to the placing of the flywheels in the vicinity of the side walls in the bucket the known jaw crusher is vulnerable in the case of damage to a side wall, for instance as a result of excessively violent collisions of the bucket with objects outside it, or as result of collisions of debris present in the bucket with a side wall. There is also a chance, in the case a shaft breaks, of a flywheel breaking through a side wall, with all the associated risks for bystanders. The known jaw crusher is not suitable for removing iron from the reduced rubble parts. In respect of current legal regulations, reduced rubble parts containing iron are unsuitable for reuse, so that a separate treatment of the reduced rubble parts is necessary in a de-ironing installation.

It is an object of the invention to provide a jaw crusher for a rubble crushing device, in particular for a mobile rubble crushing device, which jaw crusher has a sufficiently low weight to enable coupling thereof in simple manner to a movable arm of a self-propelled vehicle, for instance an excavator or a wheel loader.

It is a further object to provide a jaw crusher which can sufficiently withstand debris striking the outside or, in the interior, components of this jaw crusher.

It is another object to provide a jaw crusher which does not result in a safety hazard to the surrounding area in the unlikely event of damage occurring to the interior.

These objects are realized, and other advantages gained, with a jaw crusher having all the technical features, in combination, according to claim 1.

A jaw crusher according to the invention with only one flywheel provides the advantage of a substantial weight reduction compared to the known jaw crusher with two flywheels. Use is made here of the fact that the moment of inertia of a flywheel is determined substantially by the mass in the vicinity of the periphery of the flywheel, and a reduction of the mass in the vicinity of the shaft does not result in a substantial reduction in moment of inertia.

A jaw crusher with one flywheel suspended in the centre of a shaft as according to the invention is also safer relative to the known jaw crusher with two flywheels suspended on the sides of the grab bucket in the unlikely event of a shaft breaking, since there is an exceptionally small chance of the one flywheel breaking through a side wall.

In a jaw crusher according to the invention the flywheel is preferably coupled in symmetrical manner to the at least one motor for the purpose of setting the flywheel into rotation.

In an embodiment the flywheel is coupled to two motors engaging on the shaft on either side of the flywheel, for instance two hydromotors arranged on the shaft.

In an advantageous embodiment the flywheel is coupled to one motor, for instance a hydromotor, engaging on the periphery of the flywheel.

In an embodiment with one motor, the flywheel is preferably coupled to this motor by means of at least one V-belt.

Such a jaw crusher is for instance provided with a substantially H-shaped drive rod for coupling the shaft to the at least one movable crushing body, which drive rod comprises two legs which at their one end are coupled eccentrically to the shaft on either side of the flywheel and which at their other end are coupled pivotally to the crushing body, and which are coupled rigidly to each other by a transverse part.

A preferred embodiment of a jaw crusher according to the invention is provided with separating means for separating ferromagnetic parts from the reduced rubble parts.

The separating means comprise for instance a magnetic separator placed in the vicinity of the outlet opening.

In an advantageous embodiment the magnetic separator comprises an endless conveyor belt and a permanent magnet for generating a magnetic field on the side of the conveyor belt serving under normal conditions of use as underside, wherein the conveyor belt is for instance provided with a surface profiling which is preferably formed by ribs extending transversely of the direction of transport of the conveyor belt.

In such a jaw crusher ferromagnetic parts, particularly residues of concrete reinforcing bars, are attracted by the permanent magnet and pressed against the underside of the conveyor belt until a maximum capacity is reached and the quantity of ferromagnetic residues must be unloaded from the jaw crusher. For this purpose the jaw crusher is for instance positioned with its outlet opening above a collecting container for iron residues, and the endless belt is displaced through some distance using a drive motor present for this purpose, wherein the iron parts pressed against the belt are dragged along by the transverse ribs and out of the magnetic field generated by the magnet, where the parts are released from the belt and drop via the outlet opening into the collecting container.

Another embodiment of a jaw crusher according to the invention is provided with at least one hydraulic jack for adjusting the distance between the crushing bodies which is coupled pivotally between the grab bucket and a non-driven crushing body.

The size of the reduced rubble parts is set by adjusting said distance using such a jack.

Such a jaw crusher is preferably provided with two hydraulic jacks which are coupled pivotally between the grab bucket and a non-driven crushing body and which are each coupled by a fixed liquid conduit to a shared liquid pump.

In order to prevent overload of the device and for safety reasons in the situation in which rubble to be reduced in size is supplied which is too hard to crush, the liquid conduit is preferably provided with a pressure relief. An additional advantage of such a pressure relief is that use need not be made of prior art safety crushing plates, which are designed such that they break in the case of overload, and must therefore be replaced.

The invention will be elucidated hereinbelow on the basis of an exemplary embodiment, with reference to the drawings.

In the drawings

• Fig. 1 shows a cut-away perspective view of a first embodiment of a jaw crusher according to the invention,
• Fig. 2 shows a perspective view of a flywheel for a jaw crusher as shown in fig. 1,
• Fig. 3 shows a perspective view of a drive rod for a jaw crusher as shown in fig. 1,
• Fig. 4 shows a perspective view of a magnetic separator for a jaw crusher as shown in fig. 1,
• Fig. 5 shows a cut-away perspective view of a hydraulic adjusting device for the jaw crusher shown in fig. 1, and
• Fig. 6 shows a perspective view of the drive for a second embodiment of a jaw crusher according to the invention.

Corresponding components are designated in the figures with the same reference numerals.

Fig. 1 shows a jaw crusher 1 with a grab bucket 2 which is provided with an inlet opening 3, an outlet opening 4, a fixed crushing plate 5 which is height-adjustable relative to the bottom of grab bucket 2 and, co-acting therewith, a driven crushing plate 6 for reducing rubble parts in size therebetween, a flywheel 8 suspended on a shaft 9, a hydromotor 28 for driving flywheel 8, and a drive rod 10 coupled eccentrically to shaft 9 for the purpose of moving the driven crushing plate 6 up and downward. On its side directed toward outlet opening 4 the upper (driven) crushing plate 6 is coupled pivotally to the bottom of grab bucket 2, and can be moved up and downward on its side directed toward inlet opening 3. The space between fixed crushing plate 5 and movable crushing plate 6 narrows in the direction from inlet opening 3 to outlet opening 4. Jaw crusher 1 is provided with a coupling member 11 with which it can be coupled to the movable boom of for instance an excavator or a wheel loader.

Fig. 2 shows the drive of jaw crusher 1 of fig. 1 in more detail, with shaft 9 which is mounted with bearing housings 12 on the sides of grab bucket 2, flywheel 8 which is provided on its periphery with V-grooves 13 for a multi-V-belt (not shown) with which flywheel 8 is coupled to a hydraulic drive motor (not shown). Flywheel 8 is mounted by means of a spline toothing (not shown) on shaft 9 which is further provided on either side of flywheel 8 with eccentrics 14, to which the drive rod 10 for driving the upper crushing plate 6 is coupled.

Fig. 3 shows an H-shaped drive rod 10 which comprises two legs 15, which at their one end are coupled eccentrically to shaft 9 on either side of the flywheel and which at their other end are coupled pivotally to upper crushing plate 6 (shown in fig. 1), and which are coupled rigidly to each other by a transverse part 16.

Fig. 4 shows a magnetic separator 17 consisting of a flat conveyor belt 18 with upright transverse ribs 19, driven by a hydromotor 20 and provided with a fixing strip 21 with which the separator 17 can be fixed against the inner wall of grab bucket 2. The underside of conveyor belt 18 runs in close-fitting manner along a permanent magnet (not shown) which is enclosed by conveyor belt 18.

Fig. 5 shows the underside of grab bucket 2 with lower crushing plate 5, which is coupled close to inlet opening 3 to a hinge 22 on the bottom of grab bucket 2 and which is coupled pivotally to the bottom of grab bucket 2 close to outlet opening 4 by means of two hydraulic jacks 23, which are connected to a shared hydraulic hand pump 24 by a fixed liquid conduit (not shown) which is provided with a pressure relief (not shown). Jacks 23 are mounted pivotally on a rocker yoke 25 mounted on the bottom of grab bucket 2 and are provided with forks 26 for the purpose of the pivotal coupling to crushing plate 5. The absence of liquid hoses, which can expand, prevents the lower crushing plate 5 being able to carry out a resilient displacement. Using hand pump 24 it is possible in simple manner to vary the angle of inclination of lower crushing plate 5 relative to the bottom of grab bucket 2, and thereby the distance to the end of upper crushing plate 6 directed toward outlet opening 4.

Fig. 6 shows an alternative embodiment of a drive for an oscillating crushing plate 6, in which shaft 9 is driven by two hydromotors 27 placed on the outer ends thereof.