JPH0389201U

JPH0389201U -

Info

Publication number: JPH0389201U
Application number: JP15103789U
Authority: JP
Priority date: 1989-12-27
Filing date: 1989-12-27
Publication date: 1991-09-11

Description

[Brief explanation of drawings]

第１図は本考案の実施例を示す油圧回路図、第
２図は本考案の別実施例を示す油圧回路図であり
、第３図は従来例を示す油圧回路図である。１……油圧ポンプ、２……油圧機器、３……油
路、４……リリーフ弁装置、５Ａ……温度センサ
、５Ｂ……粘度センサ、６Ａ……第１制御手段、
６Ｂ……第２制御手段。 FIG. 1 is a hydraulic circuit diagram showing an embodiment of the present invention, FIG. 2 is a hydraulic circuit diagram showing another embodiment of the present invention, and FIG. 3 is a hydraulic circuit diagram showing a conventional example. DESCRIPTION OF SYMBOLS 1... Hydraulic pump, 2... Hydraulic equipment, 3... Oil path, 4... Relief valve device, 5A... Temperature sensor, 5B... Viscosity sensor, 6A... First control means,
6B...Second control means.

Claims

[Claims for Utility Model Registration] 1. A hydraulic system in which a relief valve device 4 is provided in an oil path 3 between a hydraulic pump 1 and a hydraulic device 2, wherein the relief valve device 4 is set to a high relief pressure state. It is configured so that it can be freely switched between the set relief pressure state and the low setting state.
A temperature sensor 5A is provided to detect the temperature of the hydraulic oil,
A first control means 6A that switches the relief valve device 4 to the low set relief pressure state when the temperature detected by the temperature sensor 5A is lower than the set value, and to the high set relief pressure state when the temperature detected by the temperature sensor 5A is lower than the set value. Hydraulic system installed. 2 A hydraulic system in which a relief valve device 4 is provided in an oil path 3 between a hydraulic pump 1 and a hydraulic device 2, and the relief valve device 4 is switched between a high set relief pressure state and a low set relief pressure state. Configure as you like,
A viscosity sensor 5B is provided to detect the viscosity of the hydraulic oil,
A second control means 6B that switches the relief valve device 4 to the low set relief pressure state when the viscosity detected by the viscosity sensor 5B is higher than the set value, and to the high set relief pressure state when the viscosity is lower than the set value. Hydraulic system installed.