Compact Machinery is a sector that has grown out of the rising cost of manual labour and increasing Health and Safety restrictions on use of manpower. The original machines were small, compared to modern equipment. The increasing versatility og modern compact hydraulic equipment has enabled a whole range of Compact machines for Agricultural and Construction use.
Compact tractors were built for use in Vineyards and Orchards from the early days. This was then followed by people building small versions of most implements specially for them. The addition of Loaders and Backhoe arms to compact tractors then grew into firms building all in one machines. one early digger was the Powerfab 125 WT towable excavator for confined spaces, which was backhoe arm on a turntable, powered by a small 4 stroke petrol engine. While early versions of the 125 WT could not drive by wheels- it moved by pulling or pushing the ground with the bucket. These models had a hydraulically operated rear spade/stabiliser with two manually adjusted outriggers/stabilisers. It could be pulled by a car or small pick-up truck from Job to Job on the wheels and the outriggers formed a draw bar. Later versions included a skid-steer hydraulically driven wheeled 125 WTD and a 360 WT with a full 360 degree slew.
Later the Japanese (citation needed) invented the tracked 360 deg Mini excavator, made by companies like Kubota, Yammaha, Hanix, and Bobcat in the USA, and JCB in the UK and others like Pel-Job of France (most major manufactures now producing (or Badge engineering some in there line up).
Compact Excavator Edit
(section from wikipedia) Some work to UK ise it required and fillout history, correct links etc
A compact hydraulic excavator or mini excavator is a tracked or wheeled vehicle with an approximate operating weight from .7 to 7.5 metric tons. It generally includes a standard backfill blade and features independent boom swing. The compact hydraulic excavator is also referred to as a mini excavator.
The hydraulic excavator is somewhat unique from other construction equipment in that all movement and functions of the machine are accomplished through the transfer of hydraulic fluid. The compact excavator's work group and blade are activated by hydraulic fluid acting upon hydraulic cylinders. The excavator's slew (rotation) and travel functions are also activated by hydraulic fluid powering hydraulic motors. Most other machines have mechanical transmissions.
Most compact hydraulic excavators have three distinct assemblies: house, undercarriage and Digger Arm.
The house structure contains the operator's compartment, engine compartment, hydraulic pump and distribution components. The house structure is attached to the top of the undercarriage via a swing bearing. The house, along with the Arm, is able to rotate or slew upon the undercarriage without limit due to a hydraulic distribution valve which supplies oil to the undercarriage components.
Slewing refers to rotating the excavator's house assembly. Unlike a conventional backhoe, the operator can slew the entire house and Arm upon the undercarriage for spoil placement, as well as slewing the arm (Boom) assembly.
The undercarriage consists of rubber or steel tracks, drive sprockets, rollers, idlers and associated components/structures. The undercarriage supports the house structure and the workgroup.
The backhoe arm of a compact hydraulic excavator consists of the boom, dipper or arm, and attachment (i.e. auger, bucket, breaker, etc.). It is connected to the front of the excavator's house structure via a swing frame that allows the backhoe to be hydraulically pivoted left or right to achieve offset digging for trenching parallel with the tracks.
Independent Boom SwingEdit
The primary purpose of boom swing is for offset digging around obstacles or along foundations, walls or forms. A secondary use is cycling in areas too narrow for cab rotation. Independent boom swing is one of the major advantages of a compact excavator over other excavation equipment.
The backfill blade is used for grading, leveling, backfilling, trenching, and general dozer work. The blade can be used to increase dump height and digging depth depending on its position in relation to the excavator's workgroup, this makes it very versatile.
In recent years, hydraulic excavator capabilities have expanded far beyond excavation tasks. With the advent of hydraulic powered attachments such as a tiltrotator, breaker, a grapple or an auger, the excavator is frequently used in many applications other than excavation and with the tiltrotator attachment, actually serves as an effective tool carrier. Many excavators feature quick-attach mounting systems for simplified attachment mounting, dramatically increasing the machine's utilization on the jobsite.
There are two distinct classes of compact excavators, conventional tail swing - units that have a rear counterweight that will extend beyond the tracks when the house rotates, and zero-tail swing - units with a house whose diameter stays within the width of the tracks through full rotation. Zero-tail swing units allow the operator to focus on digging and not watching where he or she is swinging.
List of Manufactures Edit
(some companies have been taken over)
- Case CE
- New Holland Construction
- Volvo Construction Equipment
Compact Tractors Edit
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Ride-on Mowers EditRiding (ride-on) mowers (section from wikipedia)
A popular alternative for larger lawns is the riding (or ride-on) mower. The operator is provided with a seat and controls on the mower and literally 'rides' on the machine. Most use the horizontal rotating blade system, though usually with multiple blades.
A common form of ride-on mower is the lawn tractor. These are usually designed to resemble a small agricultural tractor, with the cutting deck mounted amidships between the front and rear axles.
The drives for these mowers are in several categories. The most common transmission for tractors is a manual transmission. The second most common transmission type is a form of continuously variable transmission called the hydrostatic transmission. These transmissions take several forms, from pumps driving separate motors, which may incorporate a gear reduction, to fully integrated units containing a pump, motor and gear reduction. Hydrostatic transmissions are more expensive than mechanical transmissions but they are easier to use and can transmit greater torque to the wheels as compared to a typical mechanical transmission. The least common drive type, and the most expensive, is electric.
There have been a number of attempts to replace hydrostatic transmissions with a lower cost alternative, but these attempts, which include variable belt types (e.g., MTD's Auto Drive) and toroidal, have various performance or perception problems that has caused their market life to be short or their market penetration to be limited.
Riding lawnmowers can often mount other devices such as rototillers, snowplows, snowblowers, yard vacuums, occassionally even front buckets or fork-lift tines.
Other Compact Equipment Edit
- Compact Dumpers
- Skid Steers
- Spider Cranes
- Remote Controlled devices
- Compact Excavator Specifications and Comparisons
- Bobcat Company
- Volvo Construction Equipment
- Terex-Compact Excavators
- Kubota Tractor Corporation
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