| Class / Patent application number | Description | Number of patent applications / Date published |
|---|
| 091444000 | Relatively movable serial valves | 11 |
| 20090020003 | Anchor structure of rotation directing valve for pneumatic tool - An anchor structure of a rotation directing valve is used on a housing made from a composite material for pneumatic tools. A valve bushing in the housing is set under a cylinder. The rotation directing valve held by the valve bushing is to control a pneumatic motor in clockwise or counterclockwise rotation by moving it back and forth to alter the flow direction of compressed air. The anchor structure formed on the valve bushing anchors the rotation directing valve while the pneumatic motor rotates clockwise or counterclockwise. | 01-22-2009 |
| 20100126339 | ACTUATOR CONTROL DEVICE - An actuator control device includes a meter-in solenoid valve (V | 05-27-2010 |
| 20110179946 | PROPORTIONAL PRESSURE CONTROLLER - A proportional pressure controller includes a body having inlet, outlet, and exhaust ports. A fill valve communicates with pressurized fluid in the inlet port. A dump valve communicates with pressurized fluid from the fill valve. An inlet poppet valve opens by pressurized fluid through the fill valve. An exhaust poppet valve when closed isolates pressurized fluid from the exhaust port. An outlet flow passage communicates with pressurized fluid when the inlet poppet valve is open, and communicates with the outlet port and an exhaust/outlet common passage. A fill inlet communicates between the inlet passage and fill valve, and is isolated from the outlet flow passage, exhaust/outlet common passage, and outlet and exhaust ports in all operating conditions of the controller. | 07-28-2011 |
| 091445000 | Stop valve between working chamber and inlet and exhaust valve | 2 |
| 20130055886 | DOUBLE CHECK VALVE FOR CONSTRUCTION EQUIPMENT - An improved double check valve for a construction machine is provided, which can greatly reduce noise and hunting phenomenon by making check valves open and close within a predetermined time difference to correspond to pressure drops that occur due to an external load when a dozer blade working device is operated. The double check valve includes a hydraulic pump; a hydraulic cylinder connected to the hydraulic pump to drive a working device; a control valve installed in a flow path between the hydraulic pump and the hydraulic cylinder and shifted to control a start, a stop, and a direction change of the hydraulic cylinder; a pair of pistons installed on one side of a piston cylinder to open and close first flow paths and second flow paths provided between the control valve and the hydraulic cylinder, provided with plunger ground portions and notch portions, respectively, and dividedly formed to be shifted in opposite directions to each other when signal pressure that is introduced from any one of the first and second flow paths acts on check hydraulic pressure portions during temporary descending of the working device; a pair of check valves of which checking functions are released when the check valves are pressed through the shifting of the pistons; and a plunger installed inside the piston cylinder to move the pistons in a checking function release direction of the check valves while a flow rate of hydraulic fluid, having passed through the notch portions, forms pressure in the plunger ground portions of the pistons. | 03-07-2013 |
| 20150377259 | CONSTRUCTION EQUIPMENT PRESSURE CONTROL VALVE - A pressure control valve for a construction machine is disclosed, which prevents self-weight descent of a working device due to leakage of hydraulic fluid in a neutral position of the working device. The pressure control valve for a construction machine includes a holding valve block having a pilot signal pressure port and a drain flow path formed thereon; a holding poppet having a back pressure chamber formed therein to intercept leakage of hydraulic fluid from the hydraulic actuator to the control valve in a neutral state; a first elastic member pressing the holding poppet and elastically biasing an intercepted path between the hydraulic actuator and the control valve; a piston sliding in the holding valve block when pilot signal pressure is input through the pilot signal pressure port; a pilot poppet shifted to drain the hydraulic fluid in the back pressure chamber toward a drain flow path of the control valve in response to movement of the piston; a second elastic member pressing the pilot poppet and elastically biasing an intercepted path between the back pressure chamber of the holding poppet and the drain flow path of the control valve; and an auxiliary drain path draining the leaking hydraulic fluid through a drain path of the holding valve block if the leakage of the hydraulic fluid occurs on a check valve that opens or closes the path between the back pressure chamber of the holding poppet and the drain flow path of the control valve. | 12-31-2015 |
| 091446000 | Including motive fluid pressure or flow responsive valve (468) | 6 |
| 20080257142 | Hydraulic Pressure Control Apparatus and Hydraulic Circuit - A supply passage | 10-23-2008 |
| 20080295681 | Hydraulic system having an external pressure compensator - A hydraulic system for a machine is disclosed. The hydraulic system has a source of pressurized fluid and a fluid actuator with a first chamber. The hydraulic system also has a first valve configured to selectively fluidly communicate the source with the first chamber. The first valve further includes a first element movable between a flow passing, at which fluid from the source flows to the first chamber, and a flow blocking position, at which fluid from the source is blocked from the first chamber and a second element configured to selectively drain a control passageway associated with the first element to cause the first element to move. The hydraulic system further has a proportional pressure compensating valve configured to control a pressure of a fluid directed between the source and the first valve dependent upon the pressure of the control passageway. | 12-04-2008 |
| 20090078111 | DOUBLE CHECK VALVE HAVING FLOATING FUNCTION - A double check valve having a floating function is disclosed, which can prevent construction equipment from overturning through intercepting of a floating function even if a signal pressure is fed to the double check valve to perform the floating function in a state that an excavator is supported by a working device (e.g. a dozer blade), i.e. in a jack-up state, on a sloping site and so on. The double check valve includes a hydraulic pump; a hydraulic cylinder connected to the hydraulic pump to operate a working device; a control valve installed in flow paths between the hydraulic pump and the hydraulic cylinder, and shifted to control a start, a stop, and a direction change of the hydraulic cylinder; and a double check valve installed in flow paths between the control valve and the hydraulic cylinder, and including a pair of plungers having first diaphragms formed thereon to receive an operating pressure being applied to the hydraulic cylinder and second diaphragms formed thereon to receive a signal pressure being applied to the signal pressure flow path, and a pair of check valves being pressed to remove their check function through shifting of the plungers. Sectional areas of the first diaphragms and the second diaphragms are different from each other. | 03-26-2009 |
| 20090272257 | HYDRAULIC VALVE CIRCUIT WITH DAMAGE-CONTROL OVERRIDE - Hydraulic valve circuits capable of variably limiting respective maximum hydraulic pressures at which an assembly of bidirectional hydraulic power devices can move respective clamping members, such as forks or clamp arms, selectively in a closing movement toward each other, in an opening movement away from each other, or in a side-shifting movement in unison with each other, so as to provide damage-control capabilities for the control of the clamping members. The circuits preferably include one or more pressure-regulating valves interconnected with the assembly of power devices, and capable of variably limiting a maximum side-shifting pressure, at which said assembly can cause said side-shifting movement, in response to a maximum pressure selection. The circuits preferably include at least one override assembly, capable of overriding the maximum pressure selection to thereby lower the maximum side-shifting pressure automatically irrespective of the maximum pressure selection. | 11-05-2009 |
| 20120073431 | Digital Hydraulic Controller - A digital hydraulic controller has at least two rows of valve elements: one can connect a supply line to a controller output, the other can connect the controller output to an outlet line. The valve elements of each row are connected in parallel and are switchable individually or simultaneously in different combinations with each other and have different flow cross sections. The valve element with the smallest flow cross section is present twice in the row. A system unit has a differential cylinder and a digital hydraulic controller with four rows of valve elements, two of which are, with their common controller output, connected to the one pressure chamber of the differential cylinder, while the other two rows of valve elements are, with their common controller output, connected to the other pressure chamber of the differential cylinder. The differential cylinder can be used as a precisely adjustable linear actuator. | 03-29-2012 |
| 091447000 | Between working chamber and inlet and exhaust valve | 1 |
| 20080216644 | Antagonistic fluid control system for active and passive actuator operation - An antagonistic fluid control system, wherein the system may comprise multiple antagonistic pressure control valves operable with a single actuator, or multiple pressure control valves operable with respective antagonistic actuators. The pressure control valves are configured to provide functional and efficiency advantages, and operate together to provide several operating or valving states. A first valving state comprises an active valving state configured to actively control the movement of the load. A second valving state comprises an inactive actuation state, wherein either the return and pressure ports of one pressure control valve are closed, or only the return ports of one pressure control valve are opened, to allow the other pressure control valve to operate in an active valving state. A third valving state comprises a passive valving state, wherein the pressure control valves are operated in a slosh mode configured to allow the load to freely move or dangle. In this third passive valving state, or slosh mode, the return ports of the two pressure control valves are opened to allow fluid, and preferably local fluid, to shunt back and forth within the system. | 09-11-2008 |
