CONSTRUCTION MACHINE HAVING PLATFORM FOR MAINTENANCE WORK

• US 20120224943A1
• Filed: 09/14/2010
• Published: 09/06/2012
• Est. Priority Date: 11/11/2009
• Status: Active Grant

• Current Assignee: Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Original Assignee: Daikin Industries Ltd, Kobelco Construction Machinery Company Limited (Kobe Steel Limited)
• Inventors: Yumoto, Natsuki, Maekawa, Nobuyuki, Kusano, Hideki
• Granted Patent: US 8,668,041 B2
• Time in Patent Office: Days
• US Class Current: 414/744.2
• CPC Class Codes: B62D 33/0617 for tractors or off-the-road vehicles protective devices for drivers in case of overturning of tractors B60R21/131
• CPC Class Codes: B62D 33/0633 pivotable about a vertical axis
• CPC Class Codes: E02F 9/0833 Improving access, e.g. for maintenance, steps for improving driver's access, handrails
• CPC Class Codes: E02F 9/121 Turntables, i.e. structure rotatable about 360°

Abstract

A construction machine including: a lower propelling body; an upper slewing body having a rear region with an engine room; a slewing device for slewing the upper slewing body; and a platform cover. The slewing device includes a slewing electric motor having an electric-motor output shaft, and a speed reducer having a speed-reducer output shaft rotated more slowly than the electric-motor output shaft, the speed reducer installed forward of the engine room such that the speed-reducer output shaft points downward, the slewing electric motor disposed just above the speed reducer. The platform cover is provided on a top of the slewing electric motor, having an upper surface serving as a platform for maintenance of equipment in the engine room. The platform cover is lower than the engine cover and adjacent to a front side of the engine room.

Claims

1. A construction machine having a platform for maintenance work, comprising:

a lower propelling body;

an upper slewing body mounted on the lower propelling body through a slewing bearing slewably about an axis perpendicular to a ground surface, the upper slewing body having a rear region provided with an engine room having an upward-facing opening and housing a plurality of equipment including an engine, and an engine cover for selectively opening and closing the opening of the engine room; and

a slewing device for slewing the upper slewing body, the slewing device including;

a slewing electric motor having an electric-motor output shaft;

a speed reducer having a speed-reducer output shaft, the speed reducer being coupled to the electric-motor output shaft such that the speed-reducer output shaft is rotated, according to rotation of the electric-motor output shaft, at a speed lower than that of the rotation; and

a platform cover,

wherein;

the speed reducer is installed forward of the engine room in such a posture that the speed-reducer output shaft points downward;

the slewing electric motor is disposed just above the speed reducer; and

the platform cover is provided on a top of the slewing electric motor, and has a flat upper surface serving as a platform for maintenance work of equipment housed in the engine room,

and wherein the slewing device is disposed such that the upper surface of the platform cover is located at a position lower than the engine cover and adjacent to a front side of the engine room.

2. The construction machine as defined in claim 1, wherein the upper surface of the platform cover has a slip suppressing region for suppressing slip.

3. The construction machine as defined in claim 2, wherein the slip suppressing region includes a plurality of spaced recesses each having a bottom.

4. The construction machine as defined in claim 1, wherein the platform cover has a top wall including the upper surface on which an operator can step and a sidewall protruding downward from a peripheral edge of the top wall, the top wall and the sidewall having a shape surrounding an inner space.

5. The construction machine as defined in claim 4, wherein the platform cover comprises a plurality of ribs each protruding downward from a back surface of the top wall to enhance rigidity and strength of the platform cover.

6. The construction machine as defined in claim 4, wherein the slewing electric motor comprises a motor body and a rotational speed detector provided on a top of the motor body and operable to detect a rotational speed of the electric-motor output shaft, the rotational speed detector being disposed in the inner space.

7. The construction machine as defined in claim 1, wherein the speed reducer is coupled to the electric-motor output shaft of the slewing electric motor in such a manner that the electric-motor output shaft of the slewing electric motor points downward in parallel with the speed-reducer output shaft of the speed reducer and is offset rearward from the speed-reducer output shaft.

8. The construction machine as defined in claim 1, wherein the speed reducer comprises:

a spur gear mechanism including an input-side spur gear connected to the side of the electric-motor output shaft and an output-side spur gear connected to the side of the speed-reducer output shaft; and

a planetary gear mechanism provided just below the output-side spur gear in a vertical multi-stage manner so as to transmit the rotation of the speed-reducer output shaft while reducing a speed of the rotation.

9. The construction machine as defined in claim 8, wherein the spur gear mechanism gives a horizontal offset between the electric-motor output shaft and the speed-reducer output shaft and the slewing device is disposed such that the electric-motor output shaft is offset rearward from the speed-reducer output shaft.