Double check valve having floating function

Abstract

A double check valve having a floating function is disclosed, whereby a working device that is operated by a hydraulic cylinder having a double check valve (e.g., a dozer blade) can perform a floating function when the working device performs land readjustment of a work surface. The double check valve having a floating function includes a hydraulic pump, a hydraulic cylinder operating a working device, a control valve controlling a start, a stop, and a direction change of the hydraulic cylinder, and a double check valve installed to open / close flow paths between the control valve and the hydraulic cylinder, and having a pair of plungers dividedly formed to be shifted in opposite directions to each other when a signal pressure is applied thereto, and a pair of check valves being pressed to remove their check functions through a shifting of the plungers. When the control valve is shifted to a neutral state and a floating function mode is selected, a large chamber and a small chamber of the hydraulic cylinder are connected to each other by the double check valve.

Description

[0001] Cross References to Related Applications [0002] This application is based on and claims priority from Korean Patent Application No. 10-2006-119035 filed with the Korean Intellectual Property Office on November 29, 2006, the entire contents of which are hereby incorporated by reference. technical field [0003] The present invention relates to a double check valve with a floating function, whereby a working device (for example, a bulldozer blade) used for land leveling work on a working surface can perform a floating function. [0004] The term "float" function means that the work equipment is in an unloaded state in a state where the supply of hydraulic fluid from the hydraulic pump to the hydraulic cylinder is temporarily interrupted (at this time, for operating the work equipment (for example, a bulldozer blade) The large and small chambers of the hydraulic cylinder are connected to each other) to be operated according to the unevenness of the working surface or roa...

AI Technical Summary

Problems solved by technology

[0022] As described above, the construction equipment having the conventional double check valve has the problem that the large chamber d1 and the small chamber d2 of the hydraulic cylinder d cannot pass The check function of the check valves b and c in the

Therefore, in the case where the bulldozer blade f requires a floating function depending on the working conditions, the floating function cannot be realized

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