Abstract: A cooling system for use in a work machine is provided, in which an increase in the load imposed on a fan driving circuit and occurrence of abnormal noise can be prevented without fail by means of an inexpensive arrangement at the time of switching the rotating direction of a cooling fan. To this end, the cooling system comprises: (1) a variable displacement hydraulic pump driven by the engine; (2) a forwardly and reversely rotatable hydraulic motor operated by hydraulic oil supplied from the hydraulic pump; (3) a cooling fan driven by the hydraulic motor; (4) an electromagnetic selector valve for switching the rotating direction of the hydraulic motor between a forward direction and a reverse direction; (5) controlling means for controlling switching of the electromagnetic selector valve and controlling the hydraulic pump so as to minimize the discharge oil rate of the hydraulic pump during switching of the electromagnetic selector valve.

Abstract: A cooling system for use in a work machine is provided, in which an increase in the load imposed on a fan driving circuit and occurrence of abnormal noise can be prevented without fail by means of an inexpensive arrangement at the time of switching the rotating direction of a cooling fan. To this end, the cooling system comprises: (1) a variable displacement hydraulic pump driven by the engine; (2) a forwardly and reversely rotatable hydraulic motor operated by hydraulic oil supplied from the hydraulic pump; (3) a cooling fan driven by the hydraulic motor; (4) an electromagnetic selector valve for switching the rotating direction of the hydraulic motor between a forward direction and a reverse direction; (5) controlling means for controlling switching of the electromagnetic selector valve and controlling the hydraulic pump so as to minimize the discharge oil rate of the hydraulic pump during switching of the electromagnetic selector valve.

Abstract: A supporting structure for an operator cab on a body frame of a work machine having a floor frame with a low floor portion and a high floor portion. A vibro-isolating support provided between the low and high floor portions so as to support the operator cab resiliently. At least one of said vibro-isolating supports located at either of the low floor portion having a support axis (M—M) or the high floor portion a having support axis (N—N) inclines longitudinally at a predetermined angle (&thgr;) from a vertical axis toward the center of gravity (G) of the operator cab. Either one of the vibro-isolating supports is located at the low floor portion and the high floor portion having a vertical support axis.

Abstract: Provided is a supporting structure for an operator cab on a body frame of a work machine, having a floor frame, an operator cab being mounted on said floor frame, said floor frame having a low floor portion and a high floor portion spaced longitudinally from each other at a forward location and a rearward location in a side view, and a vibro-isolating support means being provided between said low and high floor portions and said body frame so as to support the operator cab resiliently. At least one of said vibro-isolating support means located at either of the low floor portion having a support axis (M-M) or the high floor portion a having support axis (N-N) inclines longitudinally at a predetermined angle (&thgr;) from a vertical axis toward the center of gravity (G) of the operator cab.