GB2172322A - Excavating machine - Google Patents

Abstract

An excavating machine, comprising a mainframe mounted on tracks (10) for mobility, and an array of dynamic hammer devices operable to break up hard material, and consisting of a plurality of hammer devices (13) in side-by-side relationship angled at progressively greater angles lengthwise of the array for each device from those positioned near the centre of array to those at the ends of the array. When the machine is adapted to work at the base of an excavation, an articulated boom arrangement (11, 12) detachably supports the array and has rams (22, 23) to raise and lower the arrangement to position the array of hammer devices. Alternatively, when the machine is adapted to work at the top of the excavation, a mast arrangement is provided to support the tray and the mast arrangement is raised or lowered up and down the face of the excavation to position the array of hammer devices. A scraper (14) mounted on the front of the machine is provided to gather and convey excavated material. A crushing device (17) forming part of the means to gather and convey excavated material is also provided. <IMAGE>

Description

SPECIFICATION Excavating machine This invention relates to an excavating machine and more particularly a machine for excavating in hard open cut mining and civil engineering projects.

Referring to an excavating machinethroughoutthis specification and claims, includes machines which merely break down material as well as those that both break down and remove material.

At many sites material is encountered which consists of relatively hard units which cannot be removed by many conventional excavating techniques. The present practice with such types of material involves placing explosives into drilled holes within the hard u nits and, after detonation, the rest ining fragmented material is removed by conventional civil or mining equipment. Such a technique is time consuming and expensive insofarasthe drilling and positioning of explosives is concerned, and in that respect is also dangerous, whilst equipment has to be removed from the face ofthe excavation priorto blasting, and returned thereafterto recommence excavating and drill new biast hole positions.It istherefore an object ofthe present invention to provide an excavating machinewhich can relatively continuously break up such hard material without the need for fragmentation from blasting with explosives.

In accordance with the invention there is provided an excavating machine, comprising a main frame mounted ontracks or wheels for mobility, an array of dynamic hammer devices operable to break up the hard material to be excavated, and means to support said array on said main frame.

Two preferred embodiments ofthe invention will now be described with reference to the accompanying drawings, which;- Figure 1A, is a schematic side elevation view ofthe front section of one preferred embodimentofthe machine; Figure 1 B, is a schematic side elevation view ofthe rear section ofthe machine of Figure 1 A; Figure 2, is a frontviewtaken along line 2-2 of Figure 1A; Figure 3, is a cross-sectional viewtaken along line 3-3 of Figure 1A; Figure 4, is a plan view of the discharge conveyor assembly mounted on the rear section ofthe machine of Figure 1 B; Figure 5, is a cross-sectional view taken along 5-5 of Figure 1B; Figure 6, is a cross-sectional view taken along line 6-6 of Figure 1 B; and Figure 7, is a schematic end elevation view of a second preferred embodiment of the machine.

As shown schematically in Figure 1 A and 1 B,the machineconsistsof a mainframe 21 for supporting the equipment and mounted on tracks 10 for mobility, orwheels ifthe ground conditions are suitable.The main frame supports at least one pair of boom sections 11 and 12 forming a boom arrangement controlled by hydraulic rams, namely, hydraulic ram 22 to pivotthe outer boom section 12 relative to the inner boom section 11 about pivot point 34, and hydraulic ram 23to raise and lower the boom arrangement relative to the main frame about a lower picot point (not shown) within the main frame.The outer end of the boom arrangement carries an array of dynamic hammer devices 13 supported on an support structure 24 attached in turn to a pair of spaced apart support arms 32 pivotally attached at 33 to the end of the boom arrangement with the devices 13 extending transversely ofthe boom arrangement.A control ram 25 is provided between the outer boom section 12 and the support arms 32 to allow adjustment of the vertical orientation ofthe array. It is envisaged that in order to break down hard material over a significant bench width atthefaceoftheexcavation 20,ten hammer devices as shown in Figure 2, or even more, may be necessary.Thehammerdevices 13 may be operated to all impact simultaneously, or by suitable control made to impact according to a predetermined or operator changeable sequence. As shown in Figure 2 the array of hammer devices 13 are angled transversely ofthe machine and at progressively greater angles for each device from those positioned near the centre ofthe array to the ends of the array, wherebyto allow clearance attheface ofthe excavation as excavation proceeds.As shown in Figure 2 the hammer devices are supported in individual sub-support structures 35 by bolts 36 or similar quick release mechanisms so that individual hammer devices can be readily and quickly removed and replaced for repair orservice thus keeping down timeforthe machine to a minimum. The overall support structure 24, and thereof the whole array of hammer devices, is attached to the support arms32 by detachable, preferably quick release, connections 37 whereby the whole array can be removed if necessary. In addition cushions 38 of rubber or like shock absorbing material are sandwiched between the bodies of the hammer devices 13 and their respective sub-support structures 35. Hammer devices suitable for the purposes ofthe invention are envisaged to be large, heavy duty hydraulic hammers some of which are presently available.Examples ofsuch hammersaretheHM1600 manufactured by Krupp Pty. Ltd., the H-30X manufactured by Nippon Pneumatic Mfg. Co. Ltd., the UB 23A2 manufactured by Okada, and the S2000HD manufactured by Rammer.

Material broken down by the hammer devices falls to the base of the excavation and, in the embodiment of Figures 1 Ato 6, the material is removed by a scraper blade 14 pivotally supported on the front of the machine at 19 and capable of being raised and lowered bya ram 27.Thescraperblade is forced beneath the material atthe base of the excavation face whereafter, by means of a zipperconveyor26, material is conveyed rearwardly and discharged into a hopper 15 mounted on the main frame. The drive motorforthe zipper conveyor is indicated as 28.

Alternatively, or in addition, by means of a rope, chain or hydraulics, the blade may be elevated and tipped rearwardlyto discharge the material into the hopper 15 mounted on the main frame. The scraper blade 14 may be provided with hardened teeth on its leading edge and may have a hinged flap on the blade as well as side plates for retaining material on the blade.

Gathering arms orothersuitable mechanism (not shown) may be incorporated with the scraper blade to assist in collection of the broken material. Furth ermoreasshownin Figure 1A one or more hydraulic rams 30 may be provided attached between the scraper blade 14 and the mainframeto force the blade beneath the material being excavated.

Material from the hopper 15 is transferred onto the end of a transfer conveyor arrangement 16, incorporating a pair of side by side endless conveyor belts 16a (ora single wider conveyor belt),within the main frame and which transfers the material to a discharge conveyor which in turn conveys the material to a stockpile or truck or, in some instances, a further string of conveyors. When, for conveying purposes, it is necessaryforthe material to be broken down to a smaller size, a crusher, for example a scroll type crusher 17, or other reducing machine, may be inco rporated at the bottom of the hopper 15 to reduce the material prior to discharging it onto the end ofthe transfer conveyor arrangement 16 (see Figure 3).

The transferconveyorarrangement 16 conveys material to the rear of the machine (see Figure 1 B), where it discharges into a hopper 60 which in turn directs material onto a discharge conveyor arrangement 61 consisting of an endless discharge conveyor belt 62. The discharge conveyor arrangement, including the hopper 60, is supported within a frame 63to extend upwardly and rearwardly away from the machine, with thef::ame being pivotably supported on the rear end ofthe machine via aturntablearrangement64which allowsforslewing (swinging in a horizontal plane) of the conveyor arrangement, with thesupport also being such as to allow for luffing (raising and lowering) ofthe conveyor arrangement 61 With reference to Figure 1 B,and Figure4to 6, in orderto provide for slewing and luffing, a sub-frame 65 is mounted on the rear ofthe machine to extend upwardly and rearwardlythereofasshown in Figure 1 B and is linked, by a series of slewing and luffing pulley and cable arrangements 66 and 67 respectively, to an additional sub-frame 68 carried by the frame 63 ofthe discharge conveyor arrangement 61.The slewing pulley and cable arrangement 66 comprises a pair of slewing cables 69 extending from take up drum 70on either side ofthe machine, and mounted on the main framethereof, and such asto cross each otherto opposite sides ofthe sub-frame 65 and then around self-adjusting pulley 71 before extending to anchor points 72 on the sub-frame 68 carried by the frame 63 of the discharge conveyor arrangement 61. By driving the take up drums 70 in the same direction, e.g.

clockwise or anticlockwise, it will be apparent that a cable will be drawn onto one drum whilst the other cable will unwind from the otherdrumto allowthe discharge conveyor arrangementto swing or slew to one side, whilst reversal ofthe rotation ofthe respective drums 70 will slewthe arrangement to the opposite side.

Once again, with reference to Figure 1 B, and Figures 4to 6,the luffing pulley and cable arrangement67 comprises a single luffing cable 73 extending from a take up drum 74mountedon the main frame ofthe machine and over a self-adjusting pulley 75 mounted onthesub-frame 65 andthereafteraround an idler pulley 76 on the additional sub-frame 68 from which it extends to an anchor point 77 on thesub4rame 65. It will be apparent that by winding the cable 73 on to the drum 74 the discharge conveyor arrangement 71 will be raised or luffed upwardly, whilst unwinding of the cable from the drum 74 allows forthe arrangement 61 to be lowered or luffed downwardly.

The self-adjusting pulleys 71 and 75forthe slewing and luffing pulleyand cabiearrangement66and 67 respectively, of which one is shown in more detail in Figure 5, comprise pulley 78 freely rotatable about a support yoke 79 carried by a disc85 retained within a housing 80 to be rotatable therein. A series of spherical balls 81 are received between the peripheral edge portion ofthe disc 85 and a radially inwardly and then axially inturned flange 82 on the housing to in effect form a ball bearing assembly.Each housing 80 is in turn flexibly attached by awire rope 86 to a connecting frame, namely frame 83 carried at the top of the sub-frame 65 in the case of the luffing arrangement, and a frame 84 for each of the pulley and cabie arrangementsformingthe slewing arrangement 66 and carried at either side ofthe sub-frame 65.

As shown in Figure 1A, a control cabin 18for an operator of the machine is also provided at an elevated position whereby the operator can observe and control operation of the array of hammer devices, forward movement ofthe machine and scraper blade to collect broken debris, control of tipping thereof into the hopperandthe operation of other equipment on the machine. An engine room 31 is mounted on the main frame 21 behindthecontrolcabin 18.

Figure7 ofthe drawings shows a second embodiment of the machine ofthe present invention, which machine consists of a main frame 39for supporting the equipment and mounted on tracks 40for mobility, or wheels if the ground conditions are suitable. The main frame supports a mast arrangement, comprising a pair of spaced apart masts 41 (only one shown in the side-on view of Figure 7), andthe arrangement is controlled by a hydraulic ram 42to pivotthe arrangement relative to the main frame 39. The lower end of the mast arrangement carried an array ofdynamic hammerdevices 13 and supportstructure identical to that shown in Figure3, and where appropriatethe same reference numerals have been used.The lower ends of the masts are connected at spaced apart positions to the support structure 24 by quick release pivot connections 43. A hydraulic ram 44, coupled between the mast arrangement and pivotted arms (or a pivotted bracket 45), in turn attachmentto the array support 24, allows the angle ofthe array relative to the mast arrangementto be adjusted aboutthe pivot connections 43. In orderto raise and lower the mast arrangement and the array supported thereby, each mast 41 has a pitch chain 46 extending along its length from one end to the other and anchored at lower and upper anchor points 47 and 48. Each chain cooperates with a drive sprocket 49 supported within a sleeve 51 through which the mast passes in engagement with guide rollers (notshown) within the sleeve. Asthe drive sprockets are rotatedtheirengagementwith their respective chains results in raising and lowering ofthe mast arrangement. Downward pressure is maintained on the points of the hammer array by engagement of the sprocket and chain in the lowering direction when the hammer points are in contact with the face ofthe excavation. The axis of the drive sprocket also provides the pivot point 50 about which the mast and sleeve arrangement pivots underthe action of the hydraulic ram 42.

Unlikethe machine ofthe embodiment of Figures 1 to 6 which works from the base of the excavation and also removes material from the base of the excavation, the machine of Figure 7 moves along the top of the excavation and material broken down by the hammer devices 13 falls to the base of the excavation and is removed by separate suitable collecting and transferring equipmentwhich removes the material to a dump or stockpile by haulage equipment orto trucks orion some instances a string of conveyors. When, for conveying purposes, it is necessaryforthe material to be broken down to a smaller size, a crusher, for example a scroll type crusher, or other reducing machine, may be positioned at the bottom ofthe excavation to reduce the material priorto removal.

As shown a control cabin 52 for an operator of the machine is also provided at an elevated position wherebythe operatorcan observe and control operation ofthe array of hammer devices and movement of the machine. A counterweight and engine room arrangement 53 is also mounted on the main frame 39.

Claims (9)

1. An excavating machine, comprising a main frame mounted on tracks or wheels for mobility, an array of dynamic hammer devices operableto break up hard material and support means to supportthe array on said main frame.

2. An excavating machine as claimed in Claim 1, wherein the array of hammer devices consists of a plurality of hammer devices in side-by-side relationship angled at progressively greater angles lengthwise ofthe array for each device from those positioned nearthe centre of array to those at the ends ofthe array.

3. An excavating machine as claimed in Claim 1 or 2, wherein the array of hammer devices is detachably connectedtothesupportmeans.

4. An excavating machine as claimed in any one of Claims 1 to 3, wherein each hammer device is detachably connected within the array.

5. An excavating machine as claimed in any one of Claims 1 to 4, wherein the machine is adapted to work at the top of the excavation, and wherein the support means is a mast arrangement and means are provided to raise and lowerthe mast arrangement to position the array of hammer devices.

6. An excavating machine as claimed in Claim 5, wherein said mast arrangement is adapted to move up and down the face of the excavation.

7. An excavating machine as claimed in any one of Claims 1 to 4, wherein the machine is adapted to work at the base of the excavation, and wherein said support means is an asticulated boom arrangement having meansto raise and lowerthearrangementto position the array of hammer devices.

8. An excavating machine as claimed in Claim 7, including means to gather and convey excavated material.

9. An excavating machine as claimed in Claims 7 or 8, wherein said machine further includes a crushing device forming part of the means to gather and convey excavated material.