| 摘要 |
PURPOSE:To cool a hydraulic power shifter in an effective manner, by connecting a hydraulic discharge circuit of an operating device part to a low pressure hydraulic circuit. CONSTITUTION:A high pressure pump part 2 is provided with a swash plate 9, whose angle is adjusted by an operating lever 8, around an input shaft 10, and a tip end of a plunger 12 of a variable displacement pump 11 to be set up alongside of the input shaft 10 is made contact with a surface of this swash plate 9. Each low pressure chamber 3 is installed on the circumference of the pump 11 and a fixed displacement pump 17, and they are coupled together, forming a low pressure hydraulic circuit. And, these chambers are interconnected to each other from a feed circuit 24 by way of a pressure valve 25, and a part of feed oil out of an oil pump 14 is fed to this circuit 4, having it interconnected to an oil pump 3 via an oil cooler 26. Oil is made so as to be fed to a lifting hydraulic device 5 and a controlling hydraulic device 6 from the tank 13 by an oil pump 27 whereby a hydraulic discharge circuit is interconnected to the low pressure hydraulic circuit 4 and used oil is made to be joined together.
|
