Hydraulic shovel

Abstract

A hydraulic shovel ( 1 ) in which a vehicle body ( 2 ) is provided revolvably on a traveling body ( 6 ) includes a boom ( 3 ) connected rotatably to the vehicle body ( 2 ), an arm ( 4 ) connected rotatably to the boom ( 3 ), a bucket ( 5 ) connected rotatably to the arm ( 4 ), a boom hydraulic cylinder ( 10 ) that drives the boom ( 3 ), an arm hydraulic cylinder ( 9 ) that drives the arm ( 4 ), a bucket hydraulic cylinder ( 8 ) that drives the bucket ( 5 ), and a boom control valve ( 15 ), an arm control valve ( 35 ) and a bucket control valve ( 45 ) which respectively control a flow of a working oil supplied to and discharged from the respective hydraulic cylinders ( 8, 9, 10 ), wherein the boom ( 3 ) is formed to be hollow, and the bucket control valve ( 45 ) is disposed in an interior of the boom ( 3 ).

1 . A hydraulic shovel ( 1 ) in which a vehicle body ( 2 ) is provided revolvably on a traveling body ( 6 ), comprising:
 a boom ( 3 ) connected rotatably to the vehicle body ( 2 );   an arm ( 4 ) connected rotatably to the boom ( 3 );   a bucket ( 5 ) connected rotatably to the arm ( 4 );   a boom hydraulic cylinder ( 10 ) that drives the boom ( 3 );   an arm hydraulic cylinder ( 9 ) that drives the arm ( 4 );   a bucket hydraulic cylinder ( 8 ) that drives the bucket ( 5 ); and   a boom control valve ( 15 ), an arm control valve ( 35 ) and a bucket control valve ( 45 ) which respectively control a flow of a working oil supplied to and discharged from the respective hydraulic cylinders ( 8 ,  9 ,  10 ),   wherein the boom ( 3 ) is formed to be hollow, and   the bucket control valve ( 45 ) is disposed in an interior of the boom ( 3 ).   
   
   
       2 . The hydraulic shovel as defined in  claim 1 , further comprising a boom support shaft ( 7 ) that supports the boom ( 3 ) rotatably on the vehicle body ( 2 ), wherein the bucket control valve ( 45 ) is disposed above the boom support shaft ( 7 ). 
   
   
       3 . The hydraulic shovel as defined in  claim 2 , wherein the boom control valve ( 15 ) and the arm control valve ( 35 ) are disposed in the interior of the boom ( 3 ) in series with the bucket control valve ( 45 ). 
   
   
       4 . The hydraulic shovel as defined in  claim 1 , wherein an anti rod-side oil chamber ( 47 ) and a rod-side oil chamber ( 48 ) defined by a piston ( 46 ) are provided in an interior of the bucket hydraulic cylinder ( 8 ), and the bucket control valve ( 45 ) comprises:
 a first meter-in solenoid valve (V 1 ) that controls the flow of the working oil supplied to the anti rod-side oil chamber ( 47 );   a first meter-out solenoid valve (V 2 ) that controls the flow of the working oil discharged from the anti rod-side oil chamber ( 47 );   a second meter-in solenoid valve (V 3 ) that controls the flow of the working oil supplied to the rod-side oil chamber ( 48 );   a second meter-out solenoid valve (V 4 ) that controls the flow of the working oil discharged from the rod-side oil chamber ( 48 ); and   a controller ( 30 ) that controls the flow of the working oil passing through the respective meter-in solenoid valves (V 1 , V 3 ) and the respective meter-out solenoid valves (V 2 , V 4 ) individually.