EARTH-WORKING MACHINE

Abstract: A skid-steer earth-moving machine (10) has a tool mounting head (20) supported on a pair of lifting arms (18), the altitude of the head (20) being controlled by a stabilizing linkage (23). A bucket (27) or other earth-working tool may be mounted on the head (20), controlled by a ram (29). A footplate (13) is mounted on the rear of the machine (10) to support an operator who controls the operation of the machine using "deadman's" controls (32-34).

Description: Title: "EARTH-WORKING MACHINE" BACKGROUND OF THE INVENTION f (1) Field of the Invention This invention relates to an earth-working 5 machine. The invention is particularly useful as a mini- loader which can be operated in restricted areas. ( 2) Brief Description of the Prior Art Small front-end loaders of the types sold under the Registered Trade Marks "Bobcat" (Clark Equipment Co.) 10 and "Mustang" have found ready acceptance in earth-moving applications. However, these loaders are often too large to be used e.g. in domestic gardens or horse stables where only restricted access is available via narrow gate - or doorways. In these installations, any soil, manure, rubbis 15 or the like must be removed by wheelbarrow. SUMMARY OF THE PRESENT INVENTION It is an object of the present, invention to provide an earth-working machine which is very compact yet capable of carrying out a wide range of tasks . 20 It is a preferred object to provide a machine which is highly manoeuvrable and easily controllable. It is a further preferred object to provide a machine which can be operated by an operator who may stand on a footplate at the rear of the machine or who may walk 25 behind the machine. It is a still further preferred object to provide a machine with safety (or "deadman's") controls so that the machine will stop if the operator should fall from m the machine. 30 Other preferred objects of the present invention will become apparent from the following description. In one aspect the present invention resides in an earth-working machine including: a chassis; 35 wheels or tracks supporting the chassis; drive means for the wheels or tracks; a boom pivotally mounted on the chassis; means to raise and lower the boom; a bucket or other earthmoving tool on the boom; and controls operable to control the operation of the machine, the controls being operable by an operator standing on a foot plate on the chassis or walking behind the machine. Preferably the machine has four wheels arranged in two pairs connected together to provide skid-steer drive and steering for the machine. Preferably one of each pair of wheels is driven by a hydraulic motor and is connected to the other wheel of the pair by a chain-and-sprocket drive. Preferably each hydraulic motor is driven by a common hydraulic pump driven by a constant speed internal combustion engine, the motors being individually controlled by control levers and valves to provide the skid-steer drive and steering. Preferably the boom has a pair of substantially parallel lifting arms, pivotally mounted adjacent the rear of the chassis, raised and lowered by respective hydraulic rams . Preferably a tool mounting head is mounted on the forward end of the boom and is provided with a stabilizing linkage which provides a parallelogram type linkage between the chassis and the head to maintain the altitude of the head to the chassis as the boom is raised and lowered. Preferably the earth moving tool e.g. a bucket, platform, ripping tool or the like is pivotally mounted on the head and pivotally movable relative thereto by a hydraulic ram. Preferably the controls are mounted at the rear of the chassis and are self-centering, providing "deadman's" controls stopping the machine if the operator should fall off the machine or fall over. BRIEF DESCRIPTION OF THE DRAWINGS To enable the invention to be fully understood, a preferred embodiment will now be described with reference to the accompanying drawings, in which: FIG. 1 is a side view of the machine arranged as a front-end loader with the boom lowered; FIG. 2 is a similar view but with the boom raised and the bucket lowered to a discharge position; FIG. 3 is a rear view of the machine; FIG. 4 is a side view of a post-hole digger attached to the machine; FIG. 5 is a perspective view of a load-carry platform attachment for the machine; and FIG. 6 is a side view of a forklift attachment attached to the machine. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENT The loader 10 has a chassis 11 provided with body sides 12 which are triangular in side view, the body sides having panels within a tubular steel frame. A footplate 13 extends rearwardly from the chassis to provide a support for the operator. The chassis is supported at each corner on ground wheels 14, fitted with pneumatic tyres 15, notably mounted on stub axles 16. The front axles are driven by respective hydraulic motors (not shown) , the motors being driven by a hydraulic pump (also not shown) driven by a constant speed petrol engine 17. Chains and sprockets 16a connect the pairs of wheels 14 on each side to provide a skid-steer drive and steering arrangement for the loader. A pair of lifting arms 18 are pivotally mounted at the apex of the body sides 12 at the rear of the loader. The forward ends of the arms are interconnected by a trans¬ verse shaft 19 on which is pivotally mounted a tool mount¬ ing head 20. The head 20 has a pair of upright parallel arms 21 pivotally mounted at their lower ends on the shaft 19 and connected at their upper ends by a shaft 22. A stabilizing linkage 23 is pivotally mounted at its rear end on a post 24 above the apex of the body sides. The forward end of the linkage 23 is pivotally connected to the parallel arms 21, by a pin 25, to provide a parall¬ elogram arrangement to maintain the altitude of the tool mounting head 20 to the chassis 11 as the lifting arms 18 are raised and lowered by respective hydraulic rams 26 mounted on the body sides 12. A bucket 27 has a pair of rearward lugs 28 pivot¬ ally mounted on the shaft 19. The altitude of the bucket 27 to the tool head 20 is controlled by a hydraulic ram 29 connected at one end to pin 22 and at the other end to a central lug 30, on the rear of the bucket. A pair of L-shaped grab handles 31 are provided at the rear of the loader. A respective lever 32 on each side controls the drive to the wheels 15 on that side. One lever 33 controls the rams 26 to raise and lower the lifting arms, while the other lever 34 controls the ram 29 which tilts the bucket 27 relative to the tool head 20. All the levers are self-centering to provide "deadman's" controls for the loader. In use, the operator may ride on the foot plate 13 or walk behind the loader. By operating the levers 32 he can drive and steer the loader and by operating levers 33 and 34 he can control the operation of the bucket 27. Referring to FIG. 4, a post-hole digger attach¬ ment 35 is shown mounted on the tool mounting head 20. The attachment has a tool bar 36 with a pair of rearward lugs 37 pivotally mounted on the shaft 19 and a central lug pivotally connected to the hydraulic ram 29. A pair of brackets 39 extend forwardly of the tool bar 36 and support a hydraulic motor 40 on pivot pins 41. The motor 40 is driven from the hydraulic pump on the machine via hydraulic hoses 42. An auger 43, having a spiral flyte 44 around a central shaft 45, is connected to the motor 40 to drill ~ - down through the soil, the depth of the hole drilled being controlled by the rams 26, the auger 46 being maintained 5 vertical by the hydraulic ram 29. FIG. 5 shows a lifting platform 46 which may be fitted to the tool mounting head, suitable mounting lugs (not shown) being provided on the upright support frame 47. Referring now to FIG. 6, a pair of lifting forks 10 48 may be mounted on a modified form 49 of the tool bar 36 of FIG. 4. As shown, the forks may be used to transport pallets 50 or the like supporting e.g. oil drums 51 or waste containers. Other possible uses are for cleaning out stables, 15 in market gardens and vineyards and for plumbers and drainers . The loader is extremely compact and may be driven through standard 820mm gates and so is useful for the home gardener or landscaper. The loader has the ability of the 20 "Bobcat" (Registered Trade Mark) type machines, albeit with a smaller capacity, but with the added flexibility of its compact size. Various changes and modifications may be made to the embodiment described without departing from the scope 25 of the present invention as defined in the appended claims. 30 35

Claims: CLAIMS 1. An earth-working machine including: a chassis; wheels or tracks supporting the chassis; . drive means for the wheels or tracks; a boom pivotally mounted on the chassis; means to raise or lower the boom; a bucket or other earth-moving tool on ' the boom; and .controls operable to control the operation of the machine, the controls being operable by an operator standing on a footplate on the chassis or walking behind the machine. 2. A machine as claimed in Claim 1 wherein: the machine has two pairs of wheels arranged in two pairs connected together to provide skid-steer drive; one of each pair of wheels being driven by a hydraulic motor and connected to the other wheel of the pair by a chain and sprocket drive; and each hydraulic motor is driven by a common hydraulic motor driven by an internal combustion engine and controlled by controls levers operated by the operator. 3. A machine as claimed in Claim 1 wherein: the boom has a pair of substantially parallel lifting arms pivotally mounted adjacent the rear of the chassis; at least one hydraulic ram is provided on the chassis to raise and lower the lifting arms; a tool mounting head is pivotally mounted on the forward end of the lifting arms; and a stabilizing linkage is provided between the chassis and the mounting head to maintain the altitude of the head relative to the chassis as the lifting arms are raised or lowered. 4. A machine as claimed in Claim 3 wherein: an earth-moving or load-carrying tool is pivot¬ ally mounted on the mounting head; and a hydraulic ram is provided to pivotally move the tool relative to the head. 5. A machine as claimed in any one of Claims 1 to 4 wherein: the controls are provided at or adjacent the rear of the chassis for operation by an operator standing on the footplate at the rear of the chassis or walking behind the machine, the controls being self-centering providing "deadman's" controls stopping the machine if the operator should release the controls .

Inventors: WHIFFIN KENNETH WILLIAM, WHIFFIN, KENNETH, WILLIAM
Applicants: WHIFFIN KENNETH WILLIAM, WHIFFIN, KENNETH, WILLIAM
Application year: 1983
Main classification: E02F9
IPC codes: B62D49, B66F9, E02F3, E02F9, E21B19