Machine body and working machine

Abstract

A machine body including an exhaust after-treatment apparatus that executes a reduction treatment on a predetermined oxide in exhaust gas from an engine using a liquid reducing agent. A reducing agent tank provided at a position distant from the engine stores the liquid reducing agent, and a working fluid tank positioned between the exhaust after-treatment apparatus and the reducing agent tank stores a working fluid having a high temperature at least during operation of the machine. A reducing agent supply line is arranged along the working fluid tank at a position above a level of the fluid stored in the working fluid tank to supply the liquid reducing agent from the reducing agent tank to the exhaust after-treatment apparatus. Accordingly, the liquid reducing agent stored in reducing agent tank is unlikely to be thermally affected by the engine, and the liquid reducing agent flowing through the reducing agent supply line is unlikely to be thermally affected by the fluid stored in the working fluid tank.

We claim: 
     
         1 . A machine body comprising:
 an exhaust after-treatment apparatus that executes a reduction treatment on a predetermined oxide in exhaust gas from an engine using a liquid reducing agent;   a reducing agent tank provided at a position distant from the engine to store the liquid reducing agent;   a working fluid tank positioned between the exhaust after-treatment apparatus and the reducing agent tank to store a working fluid having an high temperature during machine operation; and   a reducing agent supply line arranged along the working fluid tank at a position above a level of the fluid stored in the tank to supply the liquid reducing agent from the reducing agent tank to the exhaust after-treatment apparatus.   
     
     
         2 . The machine body according to  claim 1 , further comprising a decorative cover that covers a side surface portion of the working fluid tank, wherein
 the reducing agent supply line is arranged in a space formed between the decorative cover and the side surface portion of the tank.   
     
     
         3 . The machine body according to  claim 2 , wherein the reducing agent supply line is at least partly fixed to a tank side of the decorative cover using a fixture. 
     
     
         4 . The machine body according to  claim 3 , wherein the reducing agent supply line is at least partly fixed to the tank using a fixture. 
     
     
         5 . The machine body according to  claim 1 , further comprising:
 a storage box formed on a front portion of the machine body opposite the exhaust after-treatment apparatus, wherein said reducing agent tank is positioned inside said storage box.   
     
     
         6 . The machine body according to  claim 1 , wherein the machine body is an upper slewing body of a hydraulic excavator, and said working fluid tank storing a working fluid is a hydraulic oil tank.