A bit of history and theory
The spade is the reverse - an element of the working system of a single bucket excavator. Digging is provided by the movement of the bucket, directed downwards and towards the machine itself at a level below the installation. The main purpose is to penetrate ditches, trenches, digging pits. The principle of the backhoe was invented by an engineer from Holland A. Macari in 1763, but this idea was realized only in the nineteenth century with the appearance of a direct shovel by engineer V. Otis.
Note! There is a back and a straight shovel. The first type is required to perform work above the installation level of the machine, the second - to work below the level.
There are two types of backhoes: mechanical and hydraulic. The first are produced with a rope pull system. The bucket is rigidly fastened by pulling on the handle, which is hinged at the top of the boom. Movement of the hoisting or tension rope turns the handle.
The digging is carried out directly by pulling the bucket with a traction mechanism. When the bucket is pulled up, it is removed from the face and, together with the platform, it turns to the place of unloading. The hydraulic shovel consists of the same elements as the mechanical one, with the exception of the pillar that supports the rope. In addition, the boom is driven by hydraulic cylinders.
Differences between hydraulics and mechanics
Backhoe excavators are able to perform soil development work above their installation, but with less efficiency than a direct shovel excavator. The operating cycles of the backhoe are different, which depend on the type of drive. Differences of hydraulic excavators:
- The boom is buried in the pit simultaneously with the position of the handle;
- Filling of the bucket occurs due to its rotation relative to the handle;
- The boom is extended at the same time as the handle is turned and the bucket is turned;
- The platform is deployed together with the working equipment;
- The bucket is unloaded due to its rotation relative to the handle.
Mechanical excavators are characterized by the following:
- Both the boom and the handle penetrate into the excavation at the same time;
- The bucket is filled with a turn of the handle relative to the boom to the side of the machine;
- The boom and hilt are deepened at the same time;
- Unloading is performed by turning the handle in the direction of the boom and from the excavator.
Note! Shovel reverse allows you to accurately position the bucket in relation to the ground and the loaded vehicle.
Backhoe in another sphere
The principle of backhoe operation is used not only in excavators. This technology is successfully used for loading. Backhoe loader is a self-propelled technical tool that consists of a tractor, front shovel and backhoe. Having small dimensions and mobility, it is actively used on small-scale construction sites and excavation works.
This loader is able to perform many tasks in construction, material transportation, drilling, excavation, asphalt paving and road laying. When replacing the bucket with another tool, it can crush and break stone and concrete. There are also types of loaders with a sliding bottom, which make loading much faster.
Note! The undoubted advantage of a mobile loader is its simplicity and ease. You do not have to learn much in order to start managing it.