Swiveling work machine

1. A swiveling work machine comprising:

a swivel deck mounted to be pivotable about a vertical axis; and

a side cover for covering one lateral side on the swivel deck, an accommodating space capable of accommodating a work machine accessory being provided inside said lateral cover;

wherein said accommodating space accommodates, as said implement accessory, a work oil tank, a fuel tank and a control valve unit; and

said work oil tank is disposed at a fore-and-aft intermediate portion on one lateral side on said swivel deck, said fuel tank is disposed forwardly of said work oil tank forming a gap relative thereto, and said control valve unit is disposed upwardly of said fuel tank and longitudinally along the fore/aft direction.

2. The swiveling work machine according to claim 1 , wherein said gap accommodates a battery therein, and said control valve unit is disposed upwardly of the battery and the fuel tank.

3. The swiveling work machine according to claim 2 , wherein said battery and said control valve unit are supported to a support frame fixed to said swivel deck, and

wherein said support frame includes a pair of stays disposed erect on an upper face of the swivel deck at positions forwardly and rearwardly of the battery, a first plate mounted between vertical intermediate portions of the pair of stays and mounting the battery thereon, and a second plate connected to upper ends of the pair of stays and mounting the control valve unit thereon.

4. The swiveling work machine according to claim 3 , wherein a front portion of the second plate extends to a position upwardly of the fuel tank.

5. The swiveling work machine according to claim 2 , wherein at least one of a front lower portion of the work oil tank and a rear portion of the fuel tank extends into a portion of said gap on an inner side of the swivel deck relative to the battery.