Kubota Corporation

Yoshimi Oota

Tetsu Fukui

Shigekazu Hasegawa

Satoshi Machida

A four wheel drive working vehicle having transmission clutches separately operable for driving right and left rear wheels. Power for driving right and left front wheels is transmitted thereto from a change speed device through a front differential, while power for driving the rear wheels is transmitted thereto from the change speed device through the transmission clutches, respectively. When the front wheels are steered from a straight running position beyond a predetermined angle in order to turn the vehicle, the transmission clutch corresponding to the rear wheel lying on the inside of the turn is disengaged while the transmission clutch corresponding to the outside rear wheel remains engaged. Consequently, the rear wheel lying on the inside of the turn and describing the smallest turning radius is placed in free rotation state. The working vehicle can change running directions and make small, sharp turns smoothly without a rear differential.

Four wheel drive working vehicle having transmission clutches separately

A rolling clutch apparatus having two one-way transmission mechanisms arranged axially of a drive shaft and a driven shaft. Each transmission mechanism includes an inner ring defining a conical outside surface, an outer ring disposed coaxially with the inner ring and defining a conical inside surface, and tapered rollers arranged between the conical surfaces of the inner and outer rings. The transmission mechanisms are shiftable at the same time so that the rollers in one of the transmission mechanisms are displaced axilly to be pressed between the conical surfaces of the inner and outer rings whereby the inner and outer rings rotate together to transmit drive.

Conical roller type clutch apparatus

A power transmission comprising a drive shaft and a driven shaft connected to each other to be relatively rotatable within a predetermined range. The connection between the two shafts includes a cam member axially slidable on the driven shaft. The driven shaft carries a brake device interlocked with the cam member. When an accelerating force is transmitted from ground wheels to the driven shaft, the cam member slides axially of the driven shaft. This sliding movement causes the brake device to brake the driven shaft.

Power transmission

A grass cutting system for use on a walking operator type or a riding type lawn mower as mounted between front and rear wheels. This grass cutting system comprises a cutting blade rotatable on a vertical axis, a grass catcher disposed above the cutting blade and defining a top opening, and a housing surrounding the grass catcher. A cylindrical space is defined between the grass catcher and the housing, through which grass clippings are fed with air currents from the cutting blade to the grass catcher.

Grass cutting system having a grass catcher

A hydraulic construction for a working vehicle comprising a transmission case housing a hydraulic clutch and defining a lateral opening, and hydraulic control device mounted on an inner face of a cover attached to the transmission case to close the opening, the hydraulic control device acting to control oil flows to the hydraulic clutch. The hydraulic control device is hydraulically connectable to oil passage device connected to the hydraulic clutch when the cover is attached to the transmission case.

Transmission casing including a hydraulic clutch

A hydraulic circuit construction for a power shift transmission having logical operation valves mounted on a pressure oil supply passage connecting a hydraulic clutch to a pressure oil source, the logical operation valves being operable to engage and disengage the hydraulic clutch by opening and closing the pressure oil supply passage in response to a switching operation of a change speed device connected upstream of and in series to the hydraulic clutch. The pressure oil supply passage has mounted thereon a pressure control device including a first valve mechanism, a second valve mechanism and an orifice parallel-connected to the pressure oil supply passage, and an accumulator is mounted between the pressure control device and the hydraulic clutch to assure a speedy and smooth operation of the hydraulic clutch.

Growing community of inventors

Sakai, Japan

Yoshimi Oota