|
A plain bearing (in railroading sometimes called a solid bearing) is the simplest type of bearing, comprising just a bearing surface and no rolling elements. Therefore the journal (i.e., the part of the shaft in contact with the bearing) slides over the bearing surface. The simplest example of a plain bearing is a shaft rotating in a hole. A simple linear bearing can be a pair of flat surfaces designed to allow motion; e.g., a drawer and the slides it rests on or the ways on the bed of a lathe. Plain bearings, in general, are the least expensive type of bearing. They are also compact and lightweight, and they have a high load-carrying capacity. ==Design== The design of a plain bearing depends on the type of motion the bearing must provide. The three types of motions possible are: *''Journal'' (''friction'', ''radial'' or ''rotary'') ''bearing'': This is the most common type of plain bearing; it is simply a shaft rotating in a bearing.〔 In locomotive and railroad car applications a ''journal bearing'' specifically referred to the plain bearing once used at the ends of the axles of railroad wheel sets, enclosed by ''journal boxes'' (axleboxes).〔〔(Car and Locomotive Cyclopedia Of American Practice )〕 Axlebox bearings today are no longer plain bearings but rather are rolling-element bearings. *''Linear bearing'': This bearing provides linear motion; it may take the form of a circular bearing and shaft or any other two matching surfaces (e.g., a slide plate).〔 *''Thrust bearing'': A thrust bearing provides a bearing surface for forces acting axial to the shaft.〔 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「Plain bearing」の詳細全文を読む スポンサード リンク
|