| 摘要 |
PROBLEM TO BE SOLVED: To prevent an engine stalling, as well as to automatically change the speed stepwise, by operating a hydraulic pump to circulate the oil in a closed circuit forcibly so as to drive a hydraulic motor, and changing the swash plate angle discretely. SOLUTION: The main body of a variable hydraulic pump 13 drived by a diesel engine 12, and a hydraulic motor 10 compose a closed circuit of oil circulation by pipes 103 and 102, high pressure hoses 104 and 105, and pipes 106 and 107. The control of the speed, and the conversion of the forward movement and the backward movement are carried out bye the change of the swash plate angle of the hydraulic pump 13, and the speed is changed continuously by changing the swash plate angle continuously. The oil feeding amount is changed stepwise, by changing the swash angle of the hydraulic pump 13 to the first speed, the second speed... and the highest speed discretely. And, the speed of the diesel engine 12 is monitored, and when it is a normal speed with respect the load, the speed is raised one stage, and when it is an excessive speed, or an engine stalling foretoken speed, the speed is lowered one stage, so as to carry out the traveling at the optimum speed. |
