The patent badge is an abbreviated version of the USPTO patent document. The patent badge does contain a link to the full patent document.
The patent badge is an abbreviated version of the USPTO patent document. The patent badge covers the following: Patent number, Date patent was issued, Date patent was filed, Title of the patent, Applicant, Inventor, Assignee, Attorney firm, Primary examiner, Assistant examiner, CPCs, and Abstract. The patent badge does contain a link to the full patent document (in Adobe Acrobat format, aka pdf). To download or print any patent click here.
Patent No.:
Date of Patent:
Nov. 09, 1993
Filed:
Feb. 06, 1992
Rudolf Brunner, Baldham, DE;
Abstract
In a hydraulic control device (S) comprising a double-acting hydraulic consumer (V) which is actuable by pressure via two working conduits (4, 5) and secured in at least one working direction by a load holding valve (H) which is hydraulically openable and closable in a controlled way, further comprising a control pressure conduit (12) which is connected to a control connection of the load holding valve and selectively actuable, as well as a damping throttle (13) arranged in control pressure conduit (12), there is provided a valve (15, 15', 15', 15'', 15.sup.IV) which during the controlled closing movement of load holding valve (H, 6) is automatically responsive to a delay of the controlled closing movement which is caused by the instantaneous viscosity of the pressure medium and/or a too tight setting of damping throttle (13) and is critical as to the after-running of hydraulic consumer (V) under a load (F), with the valve switching in such a case to passage and bypassing damping throttle (13). The valve offsets the effect of a pressure medium which is too cold, and/or a setting of the damping throttle that is too tight for an intended damping action with respect to a controlled closing of the load holding valve, and it ensures the rapid closing of the load holding valve as is required for stopping and holding the load, in particular during a safety shut-off operation.