Vibratory hammer having sequentially controllable sliding gripper

Abstract

Disclosed is a vibratory hammer used to drive a pile in a foundation work of a construction site. A pair of main grip portions of a main gripper capable of gripping a pile are mounted on a pair of sliding arms capable of linear reciprocation. While the main grip portions and the sliding arms make linear reciprocation, a gap between the main grip portions is adjusted depending on a size and a shape of the pile (primary sliding operation). While a jaw pad of the main grip portion that substantially grips the pile also makes linear reciprocation by virtue of self-power of the main grip portion, the pile is gripped (secondary sliding operation). The primary and secondary sliding operations are sequentially performed.

What is claimed is: 
     
         1 . A sequentially controllable sliding gripper type vibratory hammer comprising:
 a main housing having a vibrator for striking a pile;   a pair of sliding arms provided to face each other and linearly reciprocatable inside the main housing;   an arm-actuating cylinder provided inside the main housing to move the pair of sliding arms; and   a pair of left and right main grip portions mounted on the pair of sliding arms, respectively, the main grip portions moving along with the sliding arms to grip a pile by interposing a linearly and independently reciprocatable jaw pad.   
     
     
         2 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 1 , wherein each of the main grip portions includes
 a cylinder body,   a rod that linearly slides in or out of the cylinder body, and   a jaw pad that is provided in an end of the rod in a circular plate shape and has a plurality of wedged protrusions on a grip surface for gripping the pile.   
     
     
         3 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 2 , wherein a pair of arm-actuating cylinders are provided for the pair of sliding arms, and
 each of the arm-actuating cylinders pushes or pulls each of the sliding arms in parallel.   
     
     
         4 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 3 , wherein an upper plate and a lower plate are provided over and under the main grip portion, respectively, across an interior of the main housing, and
 the pair of arm-actuating cylinders are arranged oppositely in the left and right sides of the upper and lower plates.   
     
     
         5 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 4 , further comprising a pair of left and right slide pins slidably connected to the pair of sliding arms to guide left-right linear reciprocation of the sliding arms, the pair of slide pins being provided in each of the upper and lower plates. 
     
     
         6 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 5 , wherein each of the sliding arms includes
 a front plate coupled to the main grip portion,   a side plate arranged perpendicularly to the front plate, and   a connecting bracket extending from the side plate in an integral manner and having upper and lower slide pinholes where the slide pins are inserted.   
     
     
         7 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 6 , wherein a rod passage hole where a rod of the main grip portion is inserted is formed in a center of the front plate of each of the pair of sliding arms. 
     
     
         8 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 6 , wherein a first rod pin hole where a rod pin is inserted is formed in an end of a rod of the arm-actuating cylinder, and
 the connecting bracket of the sliding arm has a second rod pin hole where the rod pin inserted into the first rod pin hole is inserted.   
     
     
         9 . The sequentially controllable sliding gripper type vibratory hammer according to  claim 1 , further comprising a subsidiary gripper configured to vertically drive a pile in a finish pile socketing, wherein the subsidiary gripper includes a fixed grip portion and a movable grip portion arranged to face each other in a lower portion of the main housing to grip an upper end of the pile.