Patent ID: 8267217

Claim:
A swivel frame for a swivel work machine, comprising: a swivel base plate supported on a traveling machine body to be pivotable about a swivel axis and mounting an engine at a rear portion thereof; a support bracket provided at a front end of the swivel base plate for supporting an excavator; a partition wall provided on the swivel base plate for partitioning space forwardly of the engine in the fore/aft direction; and a pair of right and left vertical ribs provided on the swivel base plate for interconnecting the support bracket and the partition wall; wherein said swivel base plate is divided into a rear plate portion on the rear side thereof and a front plate portion on the front side thereof, the rear plate portion being formed of a plate thinner than the front plate portion; said rear plate portion and said front plate portion are fixedly connected to each other in such in a manner that upper surfaces thereof are flush each other; a rear portion of said front plate portion projects more rearward than said partition wall; a pair of vertical walls are formed on and project from said rear plate portion; and front portions of said pair of vertical walls project more forward than said rear plate portion and are fixedly attached to the rear portion of said front plate portion and said partition wall.