MULTI-SHAFT EXCAVATING DEVICE

The present invention provides multi-shaft excavating device for forming a cast in situ diaphragm wall that is capable of forming such a wall of good linearity and is highly reliable. According to the invention, a guide shaft is provided on one or both sides of a plurality of excavating shafts which are linearly arranged and in which a jet nozzle is provided on said guide shaft. A multi-shaft excavating device with three mixing shafts for forming a cast in situ diaphragm wall comprising a first gear adapted to be rotated by the central mixing shaft, a pair of second gears in mesh engagement with said first gear, a first bevel gear that is integral with said first gear, a second bevel gear in mesh engagement with said first bevel gear and fixedly provided on a rotating shaft perpendicular to a straight line connecting the centers of said mixing shafts and cutters provided at the ends of said rotating shaft, all of which are provided in a housing maintaining an interval between said mixing shafts. With the multi-shaft excavating device of the present invention, it is possible to form such a wall of good linearity. Moreover, with the device of the present invention, since the ground is excavated in such a manner as to form a rectangular cross section by a jet stream, it is possible to improve reliability over a conventional excavating blade driven by a chain. Furthermore, with the device of the present invention, it is possible to form such a wall unit of rectangular shape, and since the reaction of the cutters is offset, good balance is obtained, and it is possible to obtain a device of high reliability due to gear driving. Dispositif excavateur à arbres multiples capable de former une paroi membrane coulée in situ présentant une bonne linéarité et extrêmement fiable. Selon la présente invention, un arbre guide se trouve sur l'un ou les deux côtés d'une pluralité d'arbres excavateurs qui sont disposés de manière linéaire, ledit arbre guide étant doté d'un éjecteur. Ledit dispositif excavateur à arbres multiples comporte trois arbres de mélange, destinés à former une paroi membrane coulée in situ, qui comprennent un premier engrenage adapté pour être mis en rotation par l'arbre de mélange central, une paire de seconds engrenages se trouvant en prise avec le premier engrenage, un premier engrenage conique solidaire du premier engrenage, un second engrenage conique se trouvant en prise avec ledit premier engrenage conique et monté à demeure sur un arbre rotatif