Hydraulic circuit for longwall mining

A technology of hydraulic circuit and working surface, applied in the field of hydraulic circuit, can solve the problems of undesired opening and backflow blocking, and achieve the effect of high cost performance, high cost performance and durability
CN102713149AInactive Publication Date: 2012-10-03TIEFENBACH CONTROL SYST
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Patent Information

Authority / Receiving Office
CN · China
Patent Type
Applications(China)
Current Assignee / Owner
TIEFENBACH CONTROL SYST
Publication Date
2012-10-03
Estimated Expiration
Not applicable · inactive patent

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Abstract

A hydraulic circuit for longwall support for use in underground mining for supporting a longwall by means of a plurality of support shields comprises a pressure monitoring device in the pressure line between the load maintaining valve and the shield control valve. Said pressure monitoring device can be a device for monitoring the piston position of the shield control valve which device signals a deviation of the set position predetermined by the shield control device from the measured actual position of the piston of the shield control valve in the form of a deviation signal. It may also be a pressure sensor which signals the deviation of the set pressure predetermined by the shield control device from the measured actual pressure in the form of a deviation signal. Signaling can be acoustic or optical.
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Description

technical field

[0001] The invention relates to a hydraulic circuit according to the preamble of claim 1 , which is used for face support in underground mining by means of a support device (shield support). Background technique

[0002] Such circuits are well known and widely used, involving hydraulic equipment controlled by their own pressure. In such hydraulic systems, the valves are preadjusted hydraulically by using the pump pressure of the hydraulic circuit. This method is realized in the support control (Ausbausteuerung). Even just two supply lines in the face support will suffice. In contrast, in external control systems the hydraulic presetting command is generated by a separate control valve which works independently of the load pressure or the pump pressure, wherein the control valve is supplied with pressure medium via a separate pressure line. Furthermore, such a system must also include separate return lines for all control volumes. However, this also increa...

Claims

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