Abstract: A bulldozer causes left and right steering clutches to engage and left and right steering brakes to release when an operating amount of a steering lever is greater than a first predetermined amount and less than a second predetermined amount, and drives a turning motor so that the rotation speed of an inside output shaft becomes lower than the rotation speed of an outside output shaft as the operating amount of the steering lever increases. A controller causes the engagement rate of an inside steering clutch to decrease and causes an inside steering brake to brake when the operating amount of the steering lever is equal to or greater than the second predetermined amount.

Abstract: A controller of a crawler type work machine controls left and right steering clutches, left and right steering brakes, and a turning motor to cause the crawler type work machine to turn in either a slow turning mode or a pivot turning mode. The controller executes a hydraulic fluid amount control to reduce a hydraulic fluid amount supplied from a hydraulic pressure supply unit to the turning motor and to increase the hydraulic fluid amount supplied from the hydraulic pressure supply unit from the hydraulic pressure supply unit to the work implement cylinder when the work implement cylinder is driven while the turning motor is being rotated.

Abstract: A shift control device and a shift control method for a vehicle for reducing shift shock by taking into account the difference in vehicle speeds before and after shifting. In one of the main inventions, the clutch pressure of another clutch (forward clutch) is controlled to match a target vehicle speed to a calculated actual vehicle speed by the time of start of the connecting operation of a selected speed stage clutch. Since such control is performed so that the vehicle speed is caused to match the target vehicle speed, an actual vehicle speed change rate is held within a predetermined range in at least the instant that the connecting operation of the selected speed stage clutch is started. Also, in another one of the main inventions, as shown in FIG.

Abstract: A shift control device and a shift control method for a vehicle for reducing shift shock by taking into account the difference in vehicle speeds before and after shifting. In one of the main inventions, the clutch pressure of another clutch (forward clutch) is controlled to match a target vehicle speed to a calculated actual vehicle speed by the time of start of the connecting operation of a selected speed stage clutch. Since such control is performed so that the vehicle speed is caused to match the target vehicle speed, an actual vehicle speed change rate is held within a predetermined range in at least the instant that the connecting operation of the selected speed stage clutch is started. Also, in another one of the main inventions, as shown in FIG.

Abstract: A transmission is provided which has a very compact system configuration and is capable of exerting high energy efficiency over all speed regions from a low speed region to a high speed region, while providing improved operability free from a torque shortage. To this end, the transmission has an input shaft, an intermediate output shaft, a planetary gear mechanism, a first pump-motor, and a second pump-motor connected to the first pump-motor, the input shaft being coupled to a first element of the planetary gear mechanism, the second pump-motor being coupled to a second element of the planetary gear mechanism, the intermediate output shaft being coupled to a third element of the planetary gear mechanism, and the transmission further comprising a switching mechanism for selectively coupling the first pump-motor to either the input shaft or the intermediate output shaft.

Abstract: A transmission is provided which has a very compact system configuration and is capable of exerting high energy efficiency over all speed regions from a low speed region to a high speed region, while providing improved operability free from a torque shortage. To this end, the transmission has an input shaft 3, an intermediate output shaft 8, a planetary gear mechanism 9, a first pump-motor 7, and a second pump-motor 15 connected to the first pump-motor 7, the input shaft 3 being coupled to a first element (planetary carrier 12) of the planetary gear mechanism 9, the second pump-motor 15 being coupled to a second element (sun gear 19) of the planetary gear mechanism 9, the intermediate output shaft 8 being coupled to a third element (ring gear 16) of the planetary gear mechanism 9, and the transmission further comprising a switching mechanism (synchromesh mechanism 6) for selectively coupling the first pump-motor 7 to either the input shaft 3 or the intermediate output shaft 8.

Abstract: A transmission is provided which has a very compact system configuration and is capable of exerting high energy efficiency over all speed regions from a low speed region to a high speed region, while providing improved operability free from a torque shortage. To this end, the transmission has an input shaft, an intermediate output shaft, a planetary gear mechanism, a first pump-motor, and a second pump-motor connected to the first pump-motor, the input shaft being coupled to a first element of the planetary gear mechanism, the second pump-motor being coupled to a second element of the planetary gear mechanism, the intermediate output shaft being coupled to a third element of the planetary gear mechanism, and the transmission further comprising a switching mechanism for selectively coupling the first pump-motor to either the input shaft or the intermediate output shaft.

Abstract: The present invention provides a drive device for a working vehicle whereby gear change shock during the forward/reverse running changeover action can be reduced while achieving shortening of cycle time and protecting various clutch mechanisms in the transmission. If a reverse running command is output from a running control device while the vehicle is running forward, an ECMV controls a braking force of a brake device so as to reduce a vehicle speed through a first prescribed speed to a second prescribed speed, and disengages the forward clutch. When the vehicle speed reaches the first prescribed speed, the ECMV puts the reverse clutch in a slipping action condition and, after the vehicle speed reaches the second prescribed speed, gradually engages the reverse clutch.

Abstract: A vehicle control system which is capable of performing a quick decelerating operation in all vehicle speed regions and setting a direct region where power from an engine is transmitted through a mechanical transmission unit only in a hydro-mechanical transmission. The vehicle control system includes an engine and a hydro-mechanical transmission and is designed to set a tractive force-vehicle speed characteristic corresponding to the direct region where power transmission from the input shaft to the intermediate output shaft of the hydro-mechanical transmission is done by the mechanical transmission unit alone in a specified engine speed region. An engine control system controls the engine and a decelerator outputs a deceleration command according to an operating amount thereof. The engine control system controls the engine to reduce engine output torque corresponding to a specified engine speed region in response to the deceleration command.

Abstract: A variable relief valve is inserted in a hydraulic piping for connecting a first pump/motor to a second pump/motor. The variable relief valve is controlled such that when shifting the transmission from forward to reverse or vice versa, a relief set pressure of the variable relief valve is reduced in response to switching of a forward/reverse shifting clutch mechanism and after completion of the switching of the forward/reverse shifting clutch mechanism, the relief set value is increased.

Abstract: A transmission is provided which has a very compact system configuration and is capable of exerting high energy efficiency over all speed regions from a low speed region to a high speed region, while providing improved operability free from a torque shortage. To this end, the transmission has an input shaft 3, an intermediate output shaft 8, a planetary gear mechanism 9, a first pump-motor 7, and a second pump-motor 15 connected to the first pump-motor 7, the input shaft 3 being coupled to a first element (planetary carrier 12) of the planetary gear mechanism 9, the second pump-motor 15 being coupled to a second element (sun gear 19) of the planetary gear mechanism 9, the intermediate output shaft 8 being coupled to a third element (ring gear 16) of the planetary gear mechanism 9, and the transmission further comprising a switching mechanism (synchromesh mechanism 6) for selectively coupling the first pump-motor 7 to either the input shaft 3 or the intermediate output shaft 8.

Abstract: A transmission system for a work vehicle, which is capable of reliably mitigating, with relatively simple arrangement, shocks caused by speed changes even in a work vehicle such as a bulldozer in which almost all operations are performed with the engine operating at full load. In the transmission system which converts the output torque of an engine into torque according to work load by operations for shifting speed gears through disengagement/engagement of friction clutches, if a downshift from a higher speed gear to a lower speed gear is effected while the engine operating at full load, the friction clutch controlling valves, controller and friction clutches allows the friction clutch corresponding to the higher speed gear to slide so as to enable power transmission and the engine controlling fuel injection system and controller allows the engine to perform high power operation (overload operation) during the sliding of the friction clutch.

Abstract: The present invention provides a drive device for a working vehicle whereby gear change shock during the forward/reverse running changeover action can be reduced while achieving shortening of cycle time and protecting various clutch mechanisms in the transmission. If a reverse running command is output from a running control device while the vehicle is running forward, an ECMV controls a braking force of a brake device so as to reduce a vehicle speed through a first prescribed speed to a second prescribed speed, and disengages the forward clutch. When the vehicle speed reaches the first prescribed speed, the ECMV puts the reverse clutch in a slipping action condition and, after the vehicle speed reaches the second prescribed speed, gradually engages the reverse clutch.

Abstract: A vehicle control system having an engine and a hydro-mechanical transmission, which further comprises a decelerator for changing target engine speed according to the operating amount of a decelerator pedal; a hydrostatic transmission unit controlling means for controlling a hydrostatic transmission unit so as to make the actual speed of the engine coincident with the target engine speed; and engine controlling means for controlling the engine such that if the target engine speed is changed from a first target value to a second target value lower than the first target value by the decelerator, the output torque of the engine is reduced, while keeping the ratio of the amount of change in the output torque of the engine to the amount of change in the target engine speed constant or substantially constant.

Abstract: A vehicle control system is disclosed which is capable of performing quick decelerating operation in all vehicle speed regions and setting a direct region where power from an engine is transmitted through a mechanical transmission unit only in a hydro-mechanical transmission. In the vehicle control system which has an engine and a hydro-mechanical transmission and is designed to set a tractive force-vehicle speed characteristic corresponding to the direct region where power transmission from the input shaft to the intermediate output shaft of the hydro-mechanical transmission is done by the mechanical transmission unit alone in a specified engine speed region, there are provided an engine control system for controlling the engine and a decelerator for outputting a deceleration command according to its operating amount. The engine control system controls the engine so as to reduce engine output torque corresponding to a specified engine speed region in response to a deceleration command from the decelerator.

Abstract: A vehicle control system having an engine and a hydro-mechanical transmission, which further comprises a decelerator for changing target engine speed according to the operating amount of a decelerator pedal; a hydrostatic transmission unit controlling means for controlling a hydrostatic transmission unit so as to make the actual speed of the engine coincident with the target engine speed; and engine controlling means for controlling the engine such that if the target engine speed is changed from a first target value to a second target value lower than the first target value by the decelerator, the output torque of the engine is reduced, while keeping the ratio of the amount of change in the output torque of the engine to the amount of change in the target engine speed constant or substantially constant.

Abstract: A variable relief valve is inserted in a hydraulic piping for connecting a first pump/motor to a second pump/motor. The variable relief valve is controlled such that when shifting the transmission from forward to reverse or vice versa, a relief set pressure of the variable relief valve is reduced in response to switching of a forward/reverse shifting clutch mechanism and after completion of the switching of the forward/reverse shifting clutch mechanism, the relief set value is increased.

Abstract: A photocurable primer composition containing (A) an acrylic resin having through an urethane linkage a polymerizable unsaturated group on its side chain and containing the polymerizable unsaturated group in an amount of 0.2 to 2.0 mol/kg in a solid content of the resin (A), (B) an urethane (meth)acrylate oligomer containing at least one polymerizable unsaturated group in one molecule, and (E) a photopolymerization initiator, and a coating method.

Abstract: A repair coating method which comprises coating a photocurable processing composition (I) onto a damaged area of a substrate to form a processed layer, followed by coating a colored base coating composition (II) onto the processed layer to form a colored base layer, and coating a photocurable clear composition (III) onto the colored base layer to form a clear layer.

Abstract: A repair coating method which comprises coating a photocurable processing composition (I) onto a damaged area of a substrate to form a processed layer, followed by coating a colored base coating composition (II) onto the processed layer to form a colored base layer, and coating a photocurable clear composition (III) onto the colored base layer to form a clear layer.