Abstract: A speed control system for a working vehicle having a stepless change speed device and an auxiliary change speed device. The speed control system comprises a speed governor for controlling rotational rate of an engine, and an accelerator lever for operating the speed governor. The speed governor is interlocked with the stepless change speed device such that the rotational rate of the engine is increased with an accelerating operation of the stepless change speed device, and is decreased with a decelerating operation of the stepless change speed device. An interlock breaker is provided for breaking the interlocking between the speed governor and stepless change speed device when the auxiliary change speed device is in a low speed state.

Abstract: In a sound-proof type engine working machine with a waste heat recovery apparatus, including a sound-proof type engine working machine which comprises a liquid cooled internal combustion engine and a working machine such as an electricity generator, a compressor and the like adapted to be driven by the engine and a waste heat recovery apparatus adapted to recover the waste heat from the engine, the engine cooling liquid within the water jacket of the engine is adapted to circulate through a waste heat recovery heat exchanger and a radiator, as well as the heat to be radiated in the radiator is adapted to be controlled by means of a radiated heat control device, and the engine and the working machine are horizontally arranged side by side each other within the sound-proof casing in a longitudinal direction thereof, an upper support frame is fixed on the upper side of the sound-proof casing, and the radiator and a radiator fan associated therewith are disposed on the upper support frame.

Abstract: A drive transmission structure for a tractor comprising a propeller shaft extending between and interconnecting an output shaft of an engine disposed forwardly of a driver's section and an input shaft of a transmission disposed rearwardly of the driver's section. The engine is disposed at a rearwardly downward slant with the output shaft thereof extending toward the input shaft of the transmission. The transmission is disposed at a forwardly upward slant with the input shaft thereof extending toward the engine output shaft.

Abstract: A hydraulic control apparatus for a transmission comprising a hydraulic change speed clutch, an oil line connecting the change speed clutch to an oil pump, an electromagnetic proportional reduction valve mounted on the oil line for varying oil pressure output to the change speed clutch in response to control current applied to the reduction valve, a microcomputer for producing the control current and applying the same to the reduction valve, and a command unit for transmitting a command to the microcomputer to engage the change speed clutch.

Abstract: A lawn mower comprising a mower unit including a mower housing defining a grass clipping side discharge opening, and a blower connected to the mower housing for communication with the discharge opening. The mower housing contains rotary cutting blades driven by a vertical drive shaft. The blower includes a blower case, a blower shaft extending substantially horizontally through the blower case toward the mower housing, and a blower fan mounted on the blower shaft inside the blower case. The blower shaft is operative connected through a shaft transmission device provided on the mower housing to a PTO shaft which receives power from the drive shaft through a bevel gear pair.

Abstract: Composite pipe adapted for use, for example, in line pipes for crude oil or natural gas producing oil wells and having excellent corrosion resistance and mechanical properties to withstand high temperatures and high pressures, the composite pipe having an outer layer made of a material comprising in % by weight 0.05 to 0.20% of C, up to 1.0% of Si, up to 2.0% of Mn, up to 1.0% of Cr, 0.2 to 2.0% of Ni, up to 1.0% of Mo, 0.05 to 0.15% of V, up to 0.1% of Al, and the balance inevitable impurities and Fe, the material being up to 0.45 in carbon equivalent expressed by: ##EQU1## an inner layer made of stainless steel, high alloy steel or like corrosion resistant alloy, and an intermediate layer substantially intermediate between the outer layer and the inner layer in composition and having a thickness of 10 to 100 .mu.m, the intermediate layer providing a boundary between the outer and inner layers and being metallurgically joint to the outer layer and the inner layer integrally therewith.

Abstract: A stepless speed change mechanism in a belt transmission device comprising a first belt passed through a groove in a drive pulley and a first groove in an intermediate pulley, and a second belt passed through a second groove in the intermediate pulley and a groove in a driven pulley for transmitting rotation from the drive pulley to the driven pulley via the intermediate pulley. The first groove and the second groove of the intermediate pulley have an axial width gradually decreasing radially inwardly of the pulley. A partition provided between and defining the first and second grooves of the intermediate pulley is movable axially of the pulley to thereby vary the pitch diameter of each of the first and second grooves and steplessly change the speed of rotation to be transmitted from the drive pulley to the driven pulley.

Abstract: There is disclosed a gait type mower constructed such that a mowing unit is mounted on a front part of a vehicle, driving wheels are provided at a rear part thereof, and handles are installed backwards. An engine and a variable speed gear interlocking therewith are loaded on the vehicle. The power is imparted from output shafts of the gear via belt transmission mechanisms to the driving wheels. An improved mower is arranged such that: the engine is placed in front of the axle, while the variable speed gear is placed behind the axle; the output shafts are positioned substantially upwardly of the axle in front of the gear; and the belt transmission mechanisms are disposed in the up-and-down directions.

Abstract: A self-propelled vehicle for use in performing work inside pipes of piping systems, for example, for cleaning or coating the inner surface of the pipe includes at least three traveling assemblies connected to the body of the vehicle by parallel link assemblies. The traveling assemblies are travaeled along the pipe inner surface to be worked on by the operation of a drive unit and transmissions while being pressed against the pipe inner surface by a collapsing assembly. During travel, a liquid can be sprayed onto the pipe inner surface by a nozzle which is rotated.

Abstract: A power vehicle is equipped with a mower which has cutters, a clipping passage for transporting grass clippings therethrough to one side of the mower, and an impeller accommodated in a housing and mounted on a lateral shaft. The housing has an outer side plate supporting the shaft and positioned closer to the center of the vehicle at its rear end than at its front end and is thereby diminished in the amount of projection. The impeller is driven by a shaft transmission coupled to a belt transmission for driving the cutters and by a belting transmission. The belting transmission includes a pulley coupled to the shaft transmission, a pulley attached to the outer end of the lateral shaft, and a belt reeved around the pulleys and drivingly movable in parallel to the outer side plate of the housing outside thereof.

Abstract: A tractor has a three-point link assembly comprising a top link and opposed lower links which are connected together by a connecting assembly at their ends toward a working implement. The connecting assembly comprises an upper connector and lower connectors removably in engagement with corresponding connectable portions of the implement. The PTO shaft of the tractor is connected to an input shaft of the implement by an extendable transmission shaft having a pair of tractor joint and implement joint at its opposite ends. The connecting assembly has a clutch for separably operatively connecting an externally splined portion of the implement input shaft to an internally splined portion of the implement joint. The clutch comprises a guide fixed to the connecting assembly and extending substantially longitudinally of the tractor, a tubular case provided in the guide movably axially thereof and an operating assembly for the case. The implement joint is inserted in the case.

Abstract: A magneto-strictive torque sensor for electrically contactlessly detecting a torque applied to a rotary shaft on the basis of a resulting change in the magnetic permeability of the surface of the shaft. Fine dents and retainer areas for retaining residual compressive stress due to the fine dents are formed on the surface of the rotary shaft. According to this arrangement, the process of magnetization resulting from the application of an exciting magnetic field and of the torque to the rotary shaft involves less magnetization due to magnetic domain wall displacement and consists principally of reversible magnetic rotation, with the result of reduced hysteresis in the magnetization process. The reduced hysteresis causes less hysteresis involved in torque detection and higher detection sensitivity, thus resulting in high accuracy of torque detection.

Abstract: A four wheel drive front mower having a grass cutting unit connected to the front of a vehicle body. This mower comprises a hydrostatic transmission, an auxiliary change speed gearing, and a propelling drive transmission. The propelling drive transmission includes a center differential for distributing output of the auxiliary change speed device to front wheels and rear wheels, a clutch for making and breaking drive transmission from the center differential to the front wheels, and a front differential for transmitting the drive from the clutch to right and left front axles. The center differential, clutch and front differential are arranged vertically and serially.

Abstract: A lawn mower comprising a cutting unit disposed between front and rear wheels, a grass discharge duct extending rearwardly from the cutting unit, and grass collecting containers each defining a top opening for receiving grass clippings sent through the discharge duct. The containers are supported by an E-shaped frame connected to, and retained by pins in, open rear ends of right and left pipe frames extending rearwardly and then upwardly from a mower body. The E-shaped frame engages the open rear ends of the pipe frames to interconnect the rear ends with a selected spacing therebetween.