Abstract: An engine compartment cover for a work machine includes left and right-hand side covers for covering the sides of an engine, and a hood for covering the top of the engine. The engine compartment cover serves to enclose the engine and demarcate an engine compartment and is capable of suppressing the noise at the operator's ear level caused by the engine operating noise passing through the engine compartment cover as far as possible, whereby the level of quietness in the operator cab can be improved.

Abstract: An operator's room (cab) situated in a region above the power train of a work machine which has an opening for maintenance purposes formed passing through a floor frame and a lid member for closing off the opening installed on the floor frame, and which achieves both good quietness characteristics and good workability during servicing. In the operator's cab of the invention, the floor section of the floor frame has a hollow box-type structure, and the lid member has a hollow box-type structure which fits into the opening in the floor section of the floor frame, and furthermore, a sealing member for sealing a gap between the floor section of the floor frame and the lid member is provided.

Abstract: An operator's room (cab) situated in a region above the power train of a work machine which has an opening for maintenance purposes formed passing through a floor frame and a lid member for closing off the opening installed on the floor frame, and which achieves both good quietness characteristics and good workability during servicing. In the operator's cab of the invention, the floor section of the floor frame has a hollow box-type structure, and the lid member has a hollow box-type structure which fits into the opening in the floor section of the floor frame, and furthermore, a sealing member for sealing a gap between the floor section of the floor frame and the lid member is provided.

Abstract: An engine compartment cover for a work machine comprising left and right-hand side covers for covering the sides of an engine, and a hood for covering the top of the engine, which serves to enclose the engine and demarcate an engine compartment and which is capable of suppressing the noise at the operator's ear level caused by the engine operating noise passing through the engine compartment cover as far as possible, whereby the level of quietness in the operator cab can be improved.

Abstract: A clutch and brake control system for a tracklaying construction vehicle is disclosed, which comprises a turning operation system and a driving brake operation system. The turning operation system is operative to carry out slow turning steering and quick turning steering of the vehicle by controlling clutches provided for right and left crawler belts for the purpose of transmitting driving force to the crawler belts and controlling brakes provided for right and left crawler belts for the purpose of stopping the rotation of the crawler belts. The driving brake operation system is operative to stop the vehicle by actuating only both of the brakes.