Hydraulic system and wind turbine generator provided therewith
First Claim
1. A hydraulic system adapted to feed oil from a hydraulic tank into a hydraulic unit through a hydraulic main line by means of a hydraulic pump placed in the hydraulic main line in order to actuate the hydraulic unit with the oil, the hydraulic system comprising:
- a bypass path branching off from a discharge side of the hydraulic pump in the hydraulic main line to the hydraulic tank and flow rate control means provided in the bypass path to control the flow rate of the bypass path;
a pressure sensor provided in an inlet of the hydraulic unit in the hydraulic main line; and
a control device to which a pressure detection value is input from the pressure sensor to control the flow rate control means based on the pressure detection value, wherein oil is circulated in the bypass path while keeping pump discharge pressure and the flow rate equal to or smaller than given specified values.
1 Assignment
0 Petitions
Accused Products
Abstract
There is provided a hydraulic pump startup control device in a hydraulic system, which avoids an overloaded state at startup to enable low-temperature, fast startup and maintaining of the temperature with low-cost means in order to improve low-temperature startability. A bypass path 19 is placed in parallel with a hydraulic main line from a hydraulic tank, and the downstream of the bypass path is made merged with the hydraulic main line. A bypass valve 3 that opens or closes the bypass path is provided in the bypass path, and a pressure sensor is provided in the inlet of a hydraulic unit in the hydraulic main line. Further, a control device 10 to which a pressure detection value in the hydraulic main line is input from the pressure sensor to open the bypass valve based on the pressure detection value upon startup of the hydraulic unit. The control device repeats on-off control to circulate oil in the bypass path while keeping the pump discharge pressure and the flow rate to open the bypass path at startup so that the actuation power of the hydraulic unit will become the maximum in order to rise the hydraulic temperature of the hydraulic main line.
-
Citations
5 Claims
-
1. A hydraulic system adapted to feed oil from a hydraulic tank into a hydraulic unit through a hydraulic main line by means of a hydraulic pump placed in the hydraulic main line in order to actuate the hydraulic unit with the oil, the hydraulic system comprising:
a bypass path branching off from a discharge side of the hydraulic pump in the hydraulic main line to the hydraulic tank and flow rate control means provided in the bypass path to control the flow rate of the bypass path;
a pressure sensor provided in an inlet of the hydraulic unit in the hydraulic main line; and
a control device to which a pressure detection value is input from the pressure sensor to control the flow rate control means based on the pressure detection value, wherein oil is circulated in the bypass path while keeping pump discharge pressure and the flow rate equal to or smaller than given specified values.- View Dependent Claims (2, 3, 4, 5)
Specification