Abstract: In a hydraulic circuit for a backhoe vehicle including a plurality of hydraulic pumps and operating valves for a pair of right and left vehicle-propelling devices and other work implements, two hydraulic circuits connected to the vehicle-propelling devices share a single unit of relief circuit adapted for selectively providing relief oil pressure in a plurality of steps. In a vehicle propelling operation or an excavating operation, the relief circuit provides a higher relief pressure to oil passages used in this operation than that provided for an all-pump-activated condition, hence, the engine output may be harnessed more efficiently.

Abstract: An adapter for operatively connecting a work implement such as a bucket or fork to a loader vehicle body. The adapter may be commonly used for connection of various types or sizes of implements. Though easy to use and manufacture, the adapter provides strong, reliable and balanced connection between the vehicle and implement through its pair of side brackets and one center bracket which are rigidly connected with each other via a common support frame and which pivotably connect in substantially straight alignment respectively with a pair of implement lift arms and one implement pivot arm extending from the vehicle body.

Abstract: A dumping apparatus for a grass catcher for rearwardly inclining the grass catcher containing grass clipping to discharge the grass clippings. The apparatus includes a guide member and a movable member mounted in the guide member, a restraining member for restraining the movement of the catcher and a bracket fixed to a rear face of the catcher. A leading end of the movable member is pivoted at a longitudinally intermediate position of the bracket and a leading end of the restraining member is pivoted at a rear upper position of the bracket, whereby the grass catcher may be moved and inclined for the dumping action.

Abstract: There is disclosed an apparatus for mounting a grass box of a mower having a machine body, a covered grass box, a mowing unit and a duct through which the grasses mowed by the mowing unit are inputted into the grass box. The apparatus includes a pair of guide rails, laid under the cover, into which the grass box is removably inserted from the rear side. In the mower having the covered grass box disposed below a handle rod, the apparatus further includes stoppers through which the grass box is rotatably removably engaged with the cover and a fixing member for fixing the grass box to the cover in a closed state.

Abstract: A two-axle four-wheel tractor is equipped at its front and rear ends with working implements, individually, which are of the same type, opposite in working direction and shiftable between a working position and a nonworking position. The tractor has a steering system for steering the front and rear four wheels in the same direction through the same angle, a running transmission system for driving only the wheels positioned toward one of the working implements which is lifted to the nonworking position or, in a special case, a system for restraining the wheels positioned rearward with respect to the direction of advance of the tractor in a straight running position without permitting steering.

Abstract: In a work vehicle including a hydraulic clutch for a transmission system, the invention discloses an art of quickly yet shocklessly controlling the engagement of the clutch by properly judging a preliminary oil pressure condition and a half-clutched condition through a detection of torque developed in the transmission system.

Abstract: A speed control system for a working vehicle comprises a hydrostatic transmission for propelling the vehicle, a hydraulic cylinder and a control valve. The hydraulic cylinder includes a cylinder case operatively connected to a control shaft for varying a swash plate angle of the hydrostatic transmission, and a piston rod fixed to a case containing the hydrostatic transmission. The control valve is fixed to the cylinder case and includes a spool extending parallel to the hydraulic cylinder and operatively connected to a foot pedal for manually controlling the hydrostatic transmission. The cylinder case is shiftable following a shift of the valve spool.

Abstract: A four wheel steering tractor comprising a grass cutting system vertically movably mounted in a lower space of the tractor between front and rear wheels. The grass cutting system carries gauge wheels disposed at opposite lateral sides in rear regions thereof. An interlocking structure between a steering wheel and the front and rear wheels includes a front drag link extending from a pitman arm toward the left (or right) front wheel, and a rear drag link extending from the pitman arm toward the right (or left) rear wheel. This interlocking structure places the center of tractor turning approximately on a straight line extending through the gauge wheels and adjacent one of the gauge wheels.

Abstract: 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.

Abstract: A device for measuring torque in a shaft without contacting the latter. A torque transmitting shaft is formed with at least one detecting magnetically anisotropic region inclined to form an angle with respect to the axis of rotation of this shaft. A detecting coil is disposed on the periphery of the detecting magnetically anisotropic region. When the detecting voltage for the detecting coil changes owing to temperature changes and time-dependent changes, the changes in the detection sensitivity and in the zero point take place, leading to errors during torque measurement. Correct measured values can be obtained by having a device for correcting such changes in sensitivity and zero point.

Abstract: A device for measuring torque in a shaft without contacting the latter. A torque transmitting shaft is formed with at least one detecting magnetically anisotropic region inclined to form an angle with respect to the axis of rotation of this shaft. A detecting coil is disposed on the periphery of the detecting magnetically anisotropic region. When the detecting voltage for the detecting coil changes owing to temperature changes and time-dependent changes, the changes in the detection sensitivity and in the zero point take place, leading to errors during torque measurement. Correct measured values can be obtained by having a device for correcting such changes in sensitivity and zero point.

Abstract: A device for measuring torque in a shaft without contacting the latter. A torque transmitting shaft is formed with at least one detecting magnetically anisotropic region inclined to form an angle with respect to the axis of rotation of this shaft. A detecting coil is disposed on the periphery of the detecting magnetically anisotropic region. When the detecting voltage for the detecting coil changes owing to temperature changes and time-dependent changes, the changes in the detection sensitivity and in the zero point take place, leading to errors during torque measurement. Correct measured values can be obtained by having a device for correcting such changes in sensitivity and zero point.

Abstract: In an overhead-valve type internal combustion engine, a crank chamber is connected in communication with one side portion of a valve actuating mechanism chamber through a breather passage composed of a passage inlet a passage portion, an outlet chamber and a passage outlet communicated to one another in order. The outlet chamber is formed in the space outside the one side portion of the valve actuating mechanism chamber so as to extend long in the direction of side-by-side arrangement of valve stems. The passage outlet is opened long in the direction of side-by-side arrangement of the valve stems in such a manner as to face the valve stems. A portion, on the side of the passage outlet, of the ceiling surface of the valve actuating mechanism chamber is formed as an inclined surface which increases its height dimension as it gets nearer to the side of rocker arms from the side of the passage outlet.

Abstract: An apparatus for controlling the posture of a front loader has booms attachable to a vehicle body which are pivotally movably upward and downward and has a work implement attached to the forward ends of the booms and pivotally movable in a scooping direction and a dumping direction. Each of the booms and the implement are pivotally movable by a single control lever independently of each other or movable simultaneously. The apparatus includes an actuating member for shifting the control lever from a boom raising position to a boom raising and dumping position when the booms are not positioned lower than a specified level. This eliminates the likelihood of the implement tilting rearwardly downward even if the booms are raised, precluding the implement from spilling the earth or sand scooped up.

Abstract: A bulldozer apparatus for a working vehicle comprising a vertically pivotable arm assembly, and a blade pivotable on a fore and aft axis extending along a center position of the vehicle. Two hydraulic cylinders are disposed at opposite sides of the fore and aft axis for causing pivotal movement of the blade such that the blade is pivotable in opposite directions with extensions of the hydraulic cylinders. Two engaging devices extend substantially longitudinally of the vehicle at opposite positions across the fore and aft axis and interconnect the blade and the arm assembly for relative pivotal movement.

Abstract: A water-cooled type internal combustion engine for a farming motor vehicle has a muffler arranged within the space on the lateral side of an engine body disposed in the fore and rear direction of the farming motor vehicle. An exhaust gas dilution pipe is externally fitted at its upper end portion to an outlet pipe of the muffler so as to provide a cooling air passage gap therebetween. The lower end portion of the dilution pipe is extended below the projected end portion of the outlet pipe. A portion of the cooling air delivered by the operation of a radiator fan so as to pass through a radiator is guided by means of a muffler cover so as to be forcedly fed into the dilution pipe through the cooling air passage gap in order to facilitate the dilution of the exhaust gas.

Abstract: A mower is provided which includes a pair of link mechanisms for mounting a cutter unit on the side of a mower body in suspended form. Each link mechanism includes a pair of lifting links. The paired lifting links are pivotably connected to the side of the mower body at opposing end portions. The other end portions of the paired lifting links are connected together so that the paired lifting links can be rotated upward and downward about the respective pivot points. The cutter unit is supported by respective intermediate portions of the lifting links in suspended form, and lifted by rotating the lifting links of the paired link mechanisms upward and downward in a linked relation.

Abstract: A hydraulic circuit for a backhoe comprising a first multiple valve, a second multiple valve, and a confluence mechanism mounted between the first and second multiple valves. The first multiple valve includes control valves connected to a first pump in parallel to one another for driving working implements. The second multiple valve includes further control valves connected to a second pump in parallel to one another for driving other working implements. The confluence mechanism is connected to a rear end of a center bypass line of the first multiple valve and to a rear end of a center bypass line of the second multiple valve. Further, the confluence mechanism, in neutral position, is connected to a return oil line for confluently returning oil from the first and second multiple valves to a tank.