Loader (equipment)#Compact front end loaders
Under a front loader is defined as a movable arm ( arm of the wheel loader ) made of steel tubes, which can be mounted on a tractor. Loaders are used in agriculture or in the municipal sector, for lifting and moving loads (hay and straw bales, manure, ...). A tractor is equipped with such a front-end loader is called front-loading tractor and then has the function of a wheel loader.
Operation
Older loaders are operated via separate lever for each function, so a lever to raise and lower, one for filling and emptying the bucket and one for any extra functions. This required frequent grasping during work. Modern front-end loader equipped with a joystick control or cross lever, the movement back and forth raises the arm of the front loader and lowers and tilts the movement to the side of the shovel. More pressure and toggle switch control auxiliary functions. Thus, up to three movements, for example, move the bucket lever, lifting the arm and closing the gripper crap performed simultaneously.
Functions
The following functions are available with front loaders:
- Lifting and lowering
- Tipping and scooping
- Rapid traverse
- Additional hydraulic connections
- Parallel guidance
- Euro quick-change frame
- Vibration damping
Lifting and lowering
Lifting takes place by the hydraulic pump of the tractor by which oil is pumped in two lift cylinders. When lowering this oil is usually displaced by the force of gravity back from the cylinder. For models with double-acting lift cylinders also lowering with hydraulic pressure. These can bring the weight of the tractor to the tool and lifting the front axle.
A gas damper in the hydraulic circuit of the lift cylinders can dampen the mechanical disturbance of the rocker by uneven ground.
Movement of the tool ( types )
With simple front-end loaders (also Klink loaders ), the front loader tools operated ( eg Erdschaufel ) by opening a latch with an electromagnet or a cable pull from the vehicle. However, this only enables you to empty the bucket. A scooping is not possible.
In so-called industrial loaders is another pair of then double-acting cylinders for hydraulic actuation devices available. This newer design allows the operator to empty the bucket from the cab, hydraulics and to use again. There are also variants with rapid traverse for fast spill. This is achieved by a special valve, the oil from the " Ankippkammer " of the hydraulic cylinder is not displaced, as usual in the hydraulic oil tank, but directed with the " Abkippkammer ".
Additional hydraulic connections can be used for tool functions ( grasping, turning, cutting ... ) or stand for the locking tool available. Depending on the manufacturer and trim are available up to four double-acting control devices.
Euro quick-change frame
Front loading industry often have a standard frame with two hooks and two loops, wherein the mounting of the tilt cylinder on the tool omitted.
Attachments / Tools
Standard tools are pitchfork, shovel, pallet forks, fork with heavy duty tines ( round bale fork) and beet basket.
Moving tools are Siloschneidzange, box rotator, gripping tools, for example, for wrapped bales, solid manure or logs.
Parallel guidance
In front loaders with a parallel guide, the angle between the tool and soil hardly changes during the lift. A parallel guide allows you to use a pallet fork. Due to the rotational movement of the rocker, the pallet would not tilt backwards parallel guide during lifting. The parallel guide compensates for this by the fork is pressed corresponding to the front or to the rear by the parallelogram of the additional arms. The parallel guide can be done mechanically ( parallelogram ) or hydraulic.
Requirements to the tractor
The tractor must be equipped with a hydraulic system that is controlled from the driver's seat. To this end, the board control devices (valves that regulate the flow of oil for each function ) can be used.
If the tractor is not equipped with a sufficient number of hydraulic control units, mostly electromagnetically operated control blocks have front loaders own, to redirect the oil flow accordingly.
The electrical connection requires a 12V power supply, which is passed through the pressure switch.
In addition, the tractor must be equipped with a mounting bracket for the front loader. This consists of two shots that are on the left and right front of the cab of the tractor. In most cases these brackets are designed so that the weight of the excavated loader distributed as far as possible over the entire length of the tractor. Modern consoles are designed so that the attachment and removal of the loader can be done in a few minutes. Frontladerkonsolen are not yet standardized so that different types would be mounted.
Front loader weight on the front of the tractor during intensive use.