英语翻译ChockIn a chock support,the canopy is a solid piece and

英语翻译
Chock
In a chock support,the canopy is a solid piece and the base may be either a solid piece or two separate parts connected by steel bars at the rear and/or the front ends.In both cases a large open space is left at the center for locating the double-acting hydraulic ram which is used to push and pull,respectively,the chain conveyor and the chock in a whole unit.This setup is also used in the shields and chock shields.
Again,all hydraulic legs are installed vertically between the base and the canopy.The number of legs ranges from 3to 6,but the four-leg chocks are by far the most popular ones.In most chock supports,there are hinge joint connections between the legs and the canopy and between the legs and the base.But in order to increase the longitudinal stability,it is reinforced mostly with a box-shaped steel frame between the base and each leg.A leg restoring device is installed around each leg at the top of the box-shaped steel frame.
The chocks are suitable for medium to hard roof.When the roof overhangs well into the gob and requires induced caving,the chocks can provide access to the gob.
Shield
Shields,a new entry in the early seventies,are characterized by the addition of a caving shield at the rear end between the base and the canopy.④The caving shields,which in general are inclined,are hinge-joint to the canopy and the base making the shield a kinematically stable support,a major advantage over the frames and the chocks.⑤
The hydraulic legs in the shields are generally inclined to provide more open space for traffic.Because the canopy,caving shield,and base are interconnected,it can well resist the horizontal force without bending the legs.Thus unlike the solid constraint in the frame/chock supports,the pin connections between the legs and canopy and between the legs and the base in a shield support make it possible that the angle of inclination of the hydraulic legs varies with the mining heights.⑥Since only the vertical component of the hydraulic leg pressure is available for supporting the roof,the actual loading capacity of the shield also varies with the mining heights.
Chock Shield
The chock shield combines the features of the chocks and the shield.As such it possesses the advantages of both.⑦
If all of the four or six legs are installed between the canopy and the base,it is called a chock shield.There are regular four-or six- leg chock shields in which all legs are vertical and parallel.Others from V or X shapes.Some canopies are a single piece and some are two pieces with a hydraulic ram at the hinge-joint.
The chock shield has the highest supporting efficiency.They are suitable for hard roof.

钢梁
在钢梁支持下,天篷是一个坚实的作品和基地既可以是坚实的一件或两部分连接钢筋,在后方和/或前端.在这两种情况下一个大的开放空间,是留在中心定位双动液压内存是用来推拉,分别为,链式输送机和钢梁整体股.这种体制也可以用来在盾牌和钢梁盾牌.
再次,全液压腿垂直安装间基地和伞盖.数目不等的双腿从3to 6 ,但四腿chocks是目前最流行的.在大多数钢梁支撑,有铰之间的连接腿和树冠之间,腿和基地.但为了增加纵向稳定性,它是钢筋大多是同一个方框形钢架之间基数,每腿.一条腿恢复设备安装大约每腿在顶部的盒形钢架.
该chocks适合中等至坚硬顶板.当顶板overhangs早已进入采空区,并要求诱导崩落,chocks可以充分利用采空区.
盾牌
盾牌,一个新入职,在七十年代初期,其特点是增设了一个放顶盾后方年底之间基地和伞盖.④对放顶盾,而在一般倾向,是铰链联合向树冠和基地,使盾牌一动稳定支持,一大优势超过了帧和chocks .⑤
液压腿在盾牌一般都倾向于提供更多休憩空间,为交通.因为天篷,放盾和基地之间相互关联,它可以抵御水平力而不弯曲双腿.因此不像固体约束在帧/钢梁支持,销之间的联系,腿部和树冠之间,腿和基地盾牌支持,使之有可能的角度倾斜的液压腿随采矿台阶.⑥自只有垂直分量的液压站压力可承托屋顶,实际承载能力的盾也有差异与矿业的高峰.
钢梁盾牌
该钢梁盾相结合的特点,该chocks和盾牌.因此,它拥有两地优势.⑦
如果所有的四或六只脚都安装之间林冠和基础,它是被称为钢梁挡箭牌.有定期的四或六腿钢梁盾牌,其中所有的双腿垂直与平行.另从V或X形.一些檐篷是一个单一的作品,有些是两件与液压内存在铰链联合.
该座屏最高支持效率.它们是否适合坚硬顶板.