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A backhoe, also called a rear actor or back actor (''colloquially known as a JCB in Ireland and UK''), is a piece of excavating equipment or digger consisting of a digging bucket on the end of a two-part articulated arm. They are typically mounted on the back of a tractor or front loader. The section of the arm closest to the vehicle is known as the boom, and the section which carries the bucket is known as the dipper or dipper-stick (the terms "boom" and "dipper" having been used previously on steam shovels). The boom is generally attached to the vehicle through a pivot known as the king-post, which allows the arm to slew left and right, usually through a total of around 200 degrees. ==Characteristics== The name "backhoe" refers to the action of the shovel, not its location on the vehicle : a backhoe digs by drawing earth backwards, rather than lifting it with a forward motion like a man shoveling, a steam shovel or a bulldozer. Confusingly, the buckets on some backhoes may be reconfigured facing forward, making them "hoes". However they are not as effective in that orientation, since the dimensions of the various components are optimized for backhoeing. Most backhoes are at their strongest curling the bucket, with the dipper arm next most powerful, and boom movements the least powerful. A backhoe loader is a tractor-like vehicle with a backhoe at one end, a front loader on the other and a swiveling seat to position the operator facing whichever he is using at the time. In North America, this arrangement is often referred to as simply a Backhoe or, when on a chassis originally derived from farm tractors, a Tractor Loader Backhoe (TLB). To differentiate, a backhoe on its own dedicated chassis may then be referred to as an "excavator", although strictly, that word includes all types of machine designed to excavate. Backhoe loaders can be designed and manufactured from the start as such, or can be the result of a farm tractor equipped with a Front End Loader (FEL) and rear backhoe. Though similar looking, the purpose-designed backhoe loaders are much stronger, with the farm variation unsuitable for heavy work. The farm variation also requires that the operator switch seats from sitting in front of the backhoe controls to the tractor seat in order to reposition the equipment while digging, and this often slows down the digging process. With the advent of hydraulic powered attachments such as a tiltrotator, breaker, a grapple or an auger, the backhoe is frequently used in many applications other than excavation and with the tiltrotator attachment, serves as an effective tool carrier. Many backhoes feature quick coupler (quick-attach) mounting systems for simplified attachment mounting, dramatically increasing the machine's utilization on the job site. Backhoes are usually employed together with loaders and bulldozers. Excavators that use a backhoe are sometimes called "trackhoes" by people who do not realize the name is due to the action of the bucket, not its location on a backhoe loader. Backhoe loaders are general-purpose tools, and are being displaced to some extent by multiple specialist tools like the excavator and the specialty front end loader, especially with the rise of the mini-excavator. On many jobsites which would have previously seen a backhoe used, a skidsteer (colloquially often called a Bobcat after the most well known manufacturer and inventor of the category) and a mini excavator will be used in conjunction to fill the backhoe's role. However, backhoes still are in general use. Sometimes a backhoe bucket is reversed to work in a power shovel configuration. This is generally when loading from a large stockpile, for picking up or filling material next to walls, to increase the reach of the machine, or working around obstacles such as pipes.〔(【引用サイトリンク】url=http://www.lehnhoff.com/symlock-adapter.html )〕 Sometimes a backhoe arm is used as a crane, by slinging the lifted object from the support linkages behind the scoop (advisably not from the teeth).〔(Guide for excavators used as cranes )〕 抄文引用元・出典: フリー百科事典『 ウィキペディア（Wikipedia）』 ■ウィキペディアで「Backhoe」の詳細全文を読む スポンサード リンク
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