GB2623566A - Machine for crushing stone or concrete - Google Patents

Abstract

A machine 500 for crushing stone or concrete comprises a first jaw 504 hinged at an upper portion 506 driven reciprocally by drive 516. A second jaw 508 hinged at an upper portion 510 constrained by bearing surface 524 resting on adjusting member 520 arranged to move upward and downward within a slot 522 under action of an actuator (420 fig. 4) to move the lower portion of the second jaw 508 relative to the lower portion of the first jaw 504, producing crushed particles of selected size. The bearing surface 524 may be angled, between 20% and 40% of the jaw 508 area, the bearing surface may be a hard material such as Hardox 450TM, powder coated. The member 520 may be EN26WTM or nickel plated.

Description

Machine for Crushing Stone or Concrete

Background

Concrete crushing machines for breaking up waste bricks and building rubble into smaller fragments are known.

A problem is that very large forces are required and these are unpredictable as there may be unknown items in the waste to be crushed and so the machines have to be built very robustly to withstand and survive the rigours of use, often in a relatively uncontrolled environment on a building site.

The problem is particularly acute in a portable machine, where size and weight constraints play a part in limiting what can be achieved in a useful size.

It has been appreciated that it may be helpful to vary the size of the crushed material for different applications, even in a portable crushing machine.

In view of the forces required, this has traditionally been achieved for example by inserting steel spacer plates manually into the machine to adjust the jaw gap, the steel plates being secured to withstand the loads imposed on the jaws.

With such arrangements, changing the crushed particle size is a time-consuming manual operation. Firstly, the machine must be turned off and the crusher box emptied. To increase the particle size, the jaw must then be pushed in while sliding the spacer plate out from behind the jaw. To decrease the particle size, the jaw must be pushed in while sliding one or more additional spacer plates in behind the jaw. Both of these processes are slow and run the risk of loose parts being lost or damaged.

It is an object of the present invention to provide a machine for crushing stone or concrete which has a more easily adjustable output particle size.

According to a first aspect of the present invention there is provided a machine for crushing stone or concrete into particles, comprising; a first jaw member hinged at an upper portion and driven reciprocally by a drive arrangement to move a first lower jaw portion relatively closer and further from a second jaw member, the second jaw member being hinged at an upper portion and having a lower portion constrained from moving away from the first lower jaw portion by means of a bearing surface resting on a member arranged to move generally up and down within at least one slot under the action of at least one actuator, wherein movement of the member in a first direction allows the second jaw to move further away from the first lower jaw portion to allow larger crushed particles to be produced and movement in a second direction constrains movement thereby producing smaller crushed particles.

With this arrangement, as a substantial force is applied to the jaws when crushing a resistant object, the member (referred to subsequently as an adjuster bar) tends to be driven into the slot and the adjuster bar resists movement of the second jaw member. An actuator such as a hydraulic ram may resist short term movement forces considerably in excess of forces it is able to deliver. Thus without requiring a substantial mechanism (such as the actuator to drive the moving jaw) an adjustable mechanism can be provided which is robust enough to withstand the unpredictable environment without its corresponding weight and complexity compromising the portability or crushing capability of the machine.

The bearing surface of the second jaw preferably comprises an inclined surface. This permits an actuator having a relatively short travel to provide a wide range of adjustment of particle size.

The bearing surface is preferably arranged at an angle between 11 degrees and 21 degrees to the second jaw, more preferably at an angle of substantially 16 degrees.

The bearing surface preferably comprises between 20% and 40% of the overall area of the second jaw, more preferably substantially 30%.

The bearing surface preferably comprises a hard material such as Hardox 4501m. The bearing surface is preferably powder coated.The member or adjuster bar preferably comprises a material such as EN26WTmand is preferably nickel plated.

The at least one actuator is preferably arranged above the at least one slot which provides a compact arrangement.

Preferably, the at least one actuator is arranged to provide at least three different positions of the second jaw relative to the first jaw. Still more preferably the at least one actuator is substantially continuously variable between the extreme positions of the second jaw.

The range of the at least one actuator is preferably substantially 150 mm.

Preferably the at least one actuator is a hydraulic ram, such as a hydraulic double acting cylinder/ram 60x30x1S0x3SOmm.

Preferably a pair of actuators is provided.

Preferably the drive is arranged to provide a torque of between 10 and 30 Nm, more preferably substantially 21.6Nm.

In one embodiment the minimum power of the motor is 7kW.

Brief description of the drawings

The present invention will now be described by way of example with reference to the accompanying drawings, in which: Figure 1 is a first side view of a prior art machine for crushing concrete, Figures 2a and 2b are further side views of a prior art machine for crushing concrete, Figure 3 is a perspective view of a crushing plate for use in the machine of Figures land 2, Figure 4 is a side view of a portable concrete crushing machine in accordance with an embodiment of the present invention, Figures 5a and 5b are further side views of a portable concrete crushing machine in accordance with an embodiment of the present invention, and Figure 6 shows a side view of the adjuster bar. Detailed Description Figure 1 shows a simplified side view of a known machine 100 suitable for crushing stone and concrete. At the top is a hopper 102 into which the material to be crushed is dropped. The hopper is supported by a main body 104 of the machine. The body also carries a motor 106 and a flywheel 110 which rotates about a shaft 108. The motor may be electric or combustion with a power output of several kW and is arranged to drive the flywheel and shaft by a belt drive (not shown). Once crushed, material exits the bottom of the main body on the right hand side (in the sense of the figure) and is directed onto an inclined conveyor belt structure 112 where it travels upwards on a belt (not shown) to discharge the crushed material. The conveyor belt structure may be retracted about a lower pivot towards the body of the machine for ease of storage and transport. The whole machine is mounted on a pair of caterpillar tracks of which one 114 is visible in the figure.

The overall length of the machine may be approximately lm (with the conveyor retracted), overall width is 800mm and the height is approximately lm. A machine of this size can readily be moved around a worksite and will fit through doorways but can still crush a significant amount of concrete per hour.

Figure 2a shows a sectional view of a portion 200 of the machine shown in Figure 1, often referred to as the crusher box. The hopper, motor, conveyor belt and caterpillar tracks are omitted for clarity.

Material to be crushed is introduced at 202 between a pair of jaws 204, 208. Jaw 204 is arranged to rotate around a shaft 206 (perpendicular to the plane of the paper) and jaw 208 is arranged to rotate about a shaft 210 (also perpendicular to the plane of the paper). The jaws carry respective crushing plates 212, 214 which are made of tough material and include vertical grooves for breaking up the introduced material. The jaw 204 is a moving jaw that is driven by the motor (not shown) to move towards and away from the fixed jaw 208. This is achieved by an eccentric drive, offset shaft, toggle tube or cam 216 which rotates about a shaft 218 (c.f. the shaft 108 in Figure 1). Figure 2a shows the cam 216 in a position whereby the jaws are as open as possible, i.e. the jaw 204 is at its furthest position from jaw 208. Jaw 208 is fixed in operation but may be adjusted to alter the size of the crushed material. The lower end of the jaw 208 is held in place relative to a fixed member 220 by a series of steel spacer plates or shims 222 between the jaw 208 and the member 220. More or fewer shims can be introduced to adjust the size of the crushed material (more shims means that the jaws are closer together in operation and the particle size of the crushed material is smaller). A chute 224 delivers the crushed material to the conveyor (412, Figure 1).

Figure 2b is identical to Figure 2a with the exception that the eccentric drive 216 is now in a position that places the jaws as close together as possible. As the drive 216 rotates, the jaw 204 continually moves closer towards and further apart from the jaw 208 to produce a "chewing" action that breaks up the material introduced at 202. The motor is typically arranged to rotate the shaft 218 at around 60 to 80 r.p.m.

Figure 3 shows a perspective view 300 of one of the plates 212, 214 from Figure 2. The plate 300 comprises alternative peaks 302 and troughs 304. The two plates will normally be arranged such that the peaks of one coincide with the peaks of the other.

The machine described with reference to Figures 1, 2 and 3 provides a robust and effective solution to large pieces of debris on a building site. By reducing the size of waste material, more effective use is made of waste removal, be it by way of trucks or skips (dumpsters), as there will be less hollow space in the containers. A particular benefit of such a machine is that it can be used to make hardcore for use on the building site itself. This provides a significant environmental benefit in that less waste material has to be removed from site and less material has to be purchased and shipped to site. For this application it is particularly advantageous that the size of the hardcore can be adjusted.

However, the adjustment process is tedious since it involves the introduction and removal of the spacer plates or shims 222. In order to do this, the machine must be powered-down and made safe (to prevent any accidental activation). The crusher box must then be emptied. To increase the particle size, the jaw 208 must then be pushed in while sliding one or more spacer plates 222 out from behind the jaw. To decrease the particle size, the jaw must be pushed in while sliding one or more additional spacer plates 222 in behind the jaw. Both of these processes are slow and run the risk of loose parts being lost or damaged Figure 4 shows a side view of a machine 400 in accordance with an embodiment of the present invention that addresses these shortcomings. The view is similar to that shown in Figure 1 and includes a hopper 402, a main body 404, motor 406, shaft 408 and flywheel 410 together with conveyor 412 and caterpillar tracks 414. In addition, an adjuster bar 416 is provided (perpendicular to the plane of the page) which may move up and down within a substantially vertical slot 418. The plates containing the slots 418 are made from EN26WTM or HardoxTm. The adjuster bar 416 is also constrained in a corresponding slot (not shown) on the other side of the machine. A linear actuator 420 is provided to move the adjuster bar 416, within the slots, between a lower position and an upper position. Another linear actuator (not shown) is provided on the other side of the machine, although a single actuator may suffice in certain circumstances with suitable positioning. The linear actuators are mounted above the slot and the adjuster bar to provide a compact machine. The adjuster bar and the linear actuator(s) replace the hard-to-adjust shim arrangement in the previous machine as will be described with reference to Figure 5 below.

Figure 5a and Figure 5b show views similar to those of Figure 2a and Figure 2b, but in respect of an embodiment of the present invention. In other words, they show the linear actuator and adjuster bar of Figure 4 in place of the shims of Figure 2.

Figures 5a and 5b show part of the crushing machine 500 in which material to be crushed is introduced at 502. The hopper, motor, conveyor belt and caterpillar tracks are omitted for clarity. A first jaw 504 is free to rotate about shaft 506 (perpendicular to the plane of the paper) and carries a crushing plate 512. The first jaw is driven by an eccentric drive 516 which rotates about a shaft 518 (also perpendicular to the plane of the paper). The eccentric drive is shown at its rightmost extent (i.e. smallest jaw opening) in both Figure 5a and Figure 5b. A chute 526 provides the crushed material to the conveyor (412, Figure 4).

A second jaw 508 is free to rotate about a shaft 510 (perpendicular to the plane of the paper) and carries a crushing plate 514. On the opposite side of the jaw from the crushing plate is provided an inclined bearing surface 524 at an angle of 16 degrees to the face of the crushing plate. The bearing surface 524 engages an adjuster bar 520 (c.f. adjuster bar 416, Figure 4) which is constrained within a slot 522 (c.f. slot 418, Figure 4). In Figure 5a, the adjuster bar is shown at the lowest possible position within the slot 522. Thanks to the arrangement of the slot and the inclined bearing surface, the jaw 50815 in a position furthest from the jaw 504 which will generate the largest possible size of crushed material.

In Figure 5b, the adjuster bar 520 is at the highest possible position within the slot 522. Thanks to interaction between the adjuster bar 520 and the inclined bearing surface 524, the jaw 508 is now in the position closest to the jaw 504 which will generate the smallest possible size of crushed material. Since the position of the jaw 504 is the same in both of the Figures, the smaller minimum jaw opening can be appreciated from Figure 5b.

The adjuster bar is moved between these two positions by the linear actuator, 420 in Figure 4, and its partner on the other side of the machine. A suitable linear actuator is a hydraulic double acting cylinder/ram 60x30x150x350mm available from Flowfit of Ludlow, United Kingdom, but the skilled reader will appreciate that alternative models will provide equivalent functionality. While the adjuster bar 520 has been shown in the two extreme positions (which provide minimum functionality of this embodiment) it is also possible for the actuator to operate to place the adjuster bar in one or more intermediate positions. A continuously-variable actuator will provide a wide variety of size options for the crushed material. The actuators in this embodiment provide 150mm of travel. The skilled reader will appreciate that actuators having different lengths of travel will affect the amount of adjustment available.

The angle of the inclined bearing surface 524 of jaw 508 relative to the angle of the slot is important and should ideally be kept as small as possible. In this embodiment, it is 16 degrees but could be between 11 degrees and 21 degrees. A linear actuator that is sufficiently strong to directly hold the jaw 508 firmly enough to resist the force of the jaw 504 in operation would be too bulky and expensive to provide for a portable machine. The jaw 508 is thus kept in place by the force applied by the adjuster bar 520 to the bearing surface 524.

The material of the adjuster bar is EN26WTM which is also nickel plated and the material of the bearing surface 524 is nickel plated Hardox 450TM to ensure that there is minimum wear between them as they hold the jaw 508 in place.

Figure 6 shows a side view of the adjuster bar 600 in one embodiment. All portions of the bar are circular in cross section, about the same centre line. The bar comprises a plate-engaging portion 602, two slot-engaging portions 604, 606 and two actuator-engaging portions 608, 610. In one example, the plate-engaging portion is 444.5mm long and has a diameter of 50mm, each slot-engaging portion is 56mm long and has a diameter of 25mm and each actuator-engaging portion has a length of 20mm and a diameter of 16mm.

In one embodiment the bearing surface need not be inclined. Provided that the jaw 508 is arranged at an angle to the vertical (with the upper portion of the jaw 508 further from the jaw 504 than the lower portion of the jaw) then the linear actuator will still effect an adjustment of the position of the jaw 508. The linear actuator will have to travel further for a particular amount of adjustment to the jaw.

Claims (18)

1. CLAIMS1. A machine for crushing stone or concrete into particles, comprising; a first jaw member hinged at an upper portion and driven reciprocally by a drive arrangement to move a first lower jaw portion relatively closer to and further from a second jaw member, the second jaw member being hinged at an upper portion and having a lower portion constrained from moving away from the first lower jaw portion by means of a bearing surface resting on a member arranged to move generally up and down within at least one slot under the action of at least one actuator, wherein movement of the member in a first direction allows the second jaw to move further away from the first lower jaw portion to allow larger crushed particles to be produced and movement in a second direction constrains movement thereby producing smaller crushed particles.
2. 2.A machine as claimed claim 1, wherein the bearing surface of the second jaw comprises an inclined surface.
3. 3.A machine as claimed in claim 2, wherein the bearing surface is arranged at an angle between 11 degrees and 21 degrees to the second jaw
4. 4. A machine as claimed in claim 2, wherein the bearing surface is arranged at an angle of substantially 16 degrees to the second jaw.
5. 5. A machine as claimed in any one of the claims 1 to 4, wherein the bearing surface comprises between 20% and 40% of the overall area of the second jaw, more preferably substantially 30%.
6. 6. A machine as claimed in any one of the claims 1 to 5, wherein the bearing surface comprises a hard material such as Hardox 450TM
7. 7. A machine as claimed in any one of the claims 1 to 6, wherein the bearing surface is powder coated.
8. 8. A machine as claimed in any one of the claims 1 to 7, wherein the member comprises a material such as EN26WTM.
9. 9. A machine as claimed in any one of the claims 1 to 8, wherein the member is nickel plated.
10. 10. A machine as claimed in any one of the claims 1 to 9, wherein the at least one actuator is arranged above the at least one slot.
11. 11. A machine as claimed in any one of the claims 1 to 10, wherein the at least one actuator is arranged to provide at least three different positions of the second jaw relative to the first jaw.
12. 12. A machine as claimed in claim 11, wherein the at least one actuator is arranged to be substantially continuously variable between the extreme positions of the second jaw.
13. 13. A machine as claimed in any one of the claims 1 to 12, wherein the range of the at least one actuator is substantially 150 mm.
14. 14. A machine as claimed in any one of the claims 1 to 13, wherein the at least one actuator is a hydraulic double acting cylinder/ram.
15. 15. A machine as claimed in any one of the claims 1 to 14, comprising a pair of actuators.
16. 16. A machine as claimed in any one of the claims 1 to 15, wherein the drive is arranged to provide a torque of between 10 and 30Nm.
17. 17. A machine as claimed in claim 16, wherein the drive is arranged to provide a torque of substantially 21.6Nm.
18. 18. A machine as claimed in any one of the claims 1 to 17, wherein the drive means has a minimum power of 7 kW.