Construction machine

1. A construction machine having a frame which is provided with a working mechanism located on the front side thereof, an engine located in a rear side of said frame, a floor panel provided on said frame in front of said engine, and an operator's seat provided on said floor panel, characterized in that said construction machine comprises:

a floor panel support mechanism provided between front end portions of said frame and floor panel, and connected to front end of said floor panel through a supporting point in tilting up and down said floor panel together with said operator's seat;

a tilting mechanism provided between said frame and said floor panel on the rear side of said floor panel support mechanism and comprising a screw rod having a base end thereof pivotally supported on said frame, and a displacement member provided between said floor panel and said screw rod and held in threaded engagement with said screw rod for translational movement according to rotation of said screw rod; and

said tilting mechanism being adapted to tilt up and down said floor panel by way of a pivoting point provided at a base end of said screw rod and a displacement point provided at said displacement member and translated to an arbitrary position, tilting up said floor panel in forward direction to a degree commensurate with a distance of travel of said displacement point in forward direction.

2. A construction machine as defined in claim 1 , wherein said tilting mechanism is mounted on a side panel of said floor panel to extend in forward and rearward directions of the machine, and said displacement point is moved forward or rearward by an externally applied driving force to said screw rod.

3. A construction machine as defined in claim 1 , wherein said tilting mechanism comprises a guide rail assembly having a base end thereof pivotally supported on the side of said frame for upward and downward pivoting movements and having a fore end extended forward in a free state; said screw rod extended along and in longitudinal direction of said guide rail assembly and rotatably supported on said guide rail assembly; and said displacement member being rotatably mounted on the side of said floor panel and held in threaded engagement with said screw rod for movement in forward and rearward directions along said guide rail assembly.

4. A construction machine as defined in claim 3 , wherein said guide rail assembly is in the form of a rectangular frame comprising a fitting base member pivotally supported on the side of said frame, a pair of rail members extended forward from said fitting base member in parallel relation with each other, and an end connector attached to and connecting fore ends of said rail members;

said screw rod being extended between said rail members, having a base end disposed in a free state and having a fore end fitted in said end connector;

said displacement member being located between said rail members of said guide rail assembly and held in threaded engagement with said screw rod; and

said displacement member being translated along said guide rail assembly upon rotationally driving a fore end of said screw rod.

5. A construction machine as defined in claim 3 , wherein said guide rail assembly is in the form of a rectangular frame comprising a fitting base member pivotally supported on the side of said frame, a pair of rail members extended forward from said fitting base member in parallel relation with each other, and an end connector attached to and connecting fore ends of said rail members;

said screw rod being extended between said rail members, and having a base end and a fore end thereof fitted in said fitting base member and said end connector, respectively;

said displacement member being located between said rail members of said guide rail assembly and held in threaded engagement with said screw rod; and

said displacement member being translated along said guide rail assembly upon rotationally driving a fore end of said screw rod.

6. A construction machine as defined in claim 3 , further comprising a support member provided on said frame in the vicinity of said engine to support a rear side portion of said floor panel; and

said guide rail assembly of said tilting mechanism having a base end thereof being pivotally supported on said support member and said displacement member of said tilting mechanism being mounted on a side panel portion of said floor panel.

7. A construction machine as defined in claim 6 , wherein said support member comprises a support base extended laterally in rightward and leftward directions over said engine, and a plural number of posts extended downward from said support base and attached to said frame;

one of said posts at a lateral side of said floor panel being angularly bent in forward direction to provide an inclined surface section thereon; and

a bracket being mounted on said inclined surface section to support a base end of said tilting mechanism.

8. A construction machine as defined in claim 1 wherein said floor panel comprises a foot rest panel supporting feet of an operator who is seated on operator's seat, a partition panel rising upward from a rear side of said foot rest panel and extended rearward over said engine, and a side panel rising upright at a lateral side of said foot rest panel; and

said displacement member of said tilting mechanism being mounted on said side panel of said floor panel.

9. A construction machine as defined in claim 1 wherein said screw rod is provided with a tool connecting portion at a fore end thereof to permit connection of a screw driving tool for rotationally driving of said screw rod.