Hydraulic oil-return device, hydraulic system and excavator

Abstract

The invention relates to a hydraulic oil-return device, a hydraulic system and an excavator. The hydraulic oil-return device is characterized in that an oil-taking check valve is arranged on an oil-return oil circuit connected with a main valve, and an oil outlet of the oil-taking check valve is connected with a bypass check valve and a radiator which are in parallel connection, so that oil flowing out from the main valve is firstly decompressed via the oil-taking check valve to reduce oil-taking pressure of the radiator to have the same protected; in addition, the hydraulic oil-return device is further characterized by being provided with an oil-temperature control device, opening pressure of the bypass check valve is regulated according to oil temperature, when the oil temperature is higher, larger opening pressure can be set so as to allow the hydraulic oil to pass through the radiator as much as possible to have the oil temperature of an oil-return oil tank lowered and radiating effect improved; similarly, when the oil temperature is lower, the bypass check valve is controlled to be opened at the lower oil pressure so as to allow the hydraulic oil to pass through the bypass check valve as much as possible to improve use efficiency of the radiator, prolong the service life thereof, and improve practicability of the hydraulic oil-return device.

Description

technical field [0001] The invention relates to the back pressure oil return technology of a hydraulic system, in particular to a hydraulic oil return device, a hydraulic system and an excavator provided with the hydraulic oil return device. Background technique [0002] At present, in order to increase the back pressure of the system, it is convenient for the hydraulic components to replenish oil while reducing the inlet pressure of the radiator, and to protect the radiator, an oil inlet check valve is installed in the hydraulic system; in order to prevent the radiator from being blocked, the oil return pressure is too high and damaged If the hydraulic components are faulty, install a bypass check valve in the hydraulic system. [0003] The common installation positions of oil inlet check valve 03, bypass check valve 04 and radiator 02 are: [0004] Such as figure 1 As shown, the oil inlet check valve 03 is installed behind the radiator 02, the bypass check valve 04 is co...

AI Technical Summary

Problems solved by technology

[0007] In view of this, the present invention aims to propose a hydraulic oil return device to solve the problem that in the existing hydraulic oil return system, the hydraulic oil is easy to damage the radiator, and when the oil pressure exceeds the bypass check valve, some high-temperature oil cannot be discharged. Heat dissipation and other issues

[0008] The invention also provides a hydraulic system and an excavator to solve the problems that in the hydraulic oil return system, the hydraulic oil is easy to damage the radiator, and when the oil pressure exceeds the bypass check valve, some high-temperature oil cannot dissipate heat.

Images