A hydraulic valve device, in particular an LS directional valve, includes a housing (1), with a pressure supply connection (P), at least one utility connection (A, B), and a load-reporting connection, and includes a controller (5) moveable in two directions to at least partly actuate fluid those connections. An adjustable stop device (25, 31, 47, 59) restricts the stroke length of the travel movements of the controller (5) or parts of the stroke length in either direction. The stop device (25, 31, 47, 59) has a stop surface (25) facing in one movement direction and a second stop surface (47) facing in the other movement direction on the same axial end region (19) of a slider piston (5). A counter stop (31, 59) is provided for each stop surface (25, 47). Both counter stops are on the respective same housing end region (11) of the housing (1) in a positionally adjustable manner.

Disclosed is an energy-recycling hydraulic control main valve, which is provided with end covers, a valve core, a left one-way valve and a right one-way valve; the left one-way valve is composed of a left valve seat, a left cone valve core and a left spring; a conical surface of the left cone valve core is closely attached to a left conical surface of the valve core by the spring force; the right one-way valve is composed of a right valve seat, a right cone valve core and a right spring; and a conical surface of the right cone valve core is closely attached to a right conical surface of the valve core by spring force. The hydraulic main control valve can not only limit the falling speed of a piston, but use the potential energy generated by the gravity action on the piston, thereby achieving energy recycling.

A hydraulic system includes a hydraulic pump to output an operation fluid, first and second hydraulic devices to be operated by the operation fluid, first and second control valves to control the first and second hydraulic device, respectively, first and second communication tubes connecting the first hydraulic device to the first control valve, a supply fluid tube connecting the first control valve to the second control valve, the supply fluid tube being configured to supply the return fluid to the second control valve, first and second connection fluid tubes disposed on the first control valve, a discharge fluid tube connected to the first control valve, first and second branching fluid tubes branched from the first and second connection fluid tubes, respectively, first and second throttles disposed on the first and second branching fluid tubes, respectively, the second throttle being smaller than the first throttle.

A hydraulic valve having a hollow valve body configured with a supply port and a supply port. The hollow valve body has several different internal diameters. An elongate spool is reciprocally received in the body and has a large diameter annular spool ring oriented adjacent a sensing land inside the hollow body forming a gap with a sensing land to cause a pressure drop across the gap in response to a flow of fluid from the pressure port through the gap to the control port. A servomotor reciprocally drives the spool lengthwise of the valve body against a spring force. When flow of fluid occurs in response to servomotor movement of the spool, the pressure drop across the gap combined with the spring force determines a pressure balanced location to which the spool is moved.

A hydraulic valve having a hollow valve body configured with a supply port and a supply port. The hollow valve body has several different internal diameters. An elongate spool is reciprocally received in the body and has a large diameter annular spool ring oriented adjacent a sensing land inside the hollow body forming a gap with a sensing land to cause a pressure drop across the gap in response to a flow of fluid from the pressure port through the gap to the control port. A servomotor reciprocally drives the spool lengthwise of the valve body against a spring force. When flow of fluid occurs in response to servomotor movement of the spool, the pressure drop across the gap combined with the spring force determines a pressure balanced location to which the spool is moved.

A control valve has a first and second pilot chambers facing both ends of a spool, a signal pressure passage configured to lead a pilot pressure of the first and second pilot chambers to another device other than the control valve as a signal pressure, a communication groove configured to allow the first pilot chamber and the signal pressure passage to communicate with each other, a communication hole configured to allow the second pilot chamber and the signal pressure passage to communicate with each other, and a check valve interposed in the communication hole, and the check valve has a poppet portion configured to open or close the communication hole and a spacer portion configured to regulate a moving amount of the poppet portion in an open direction, and the control valve further includes a movement regulating portion configured to regulate movement of the spacer portion toward the poppet portion.

A control valve has a first and second pilot chambers facing both ends of a spool, a signal pressure passage configured to lead a pilot pressure of the first and second pilot chambers to another device other than the control valve as a signal pressure, a communication groove configured to allow the first pilot chamber and the signal pressure passage to communicate with each other, a communication hole configured to allow the second pilot chamber and the signal pressure passage to communicate with each other, and a check valve interposed in the communication hole, and the check valve has a poppet portion configured to open or close the communication hole and a spacer portion configured to regulate a moving amount of the poppet portion in an open direction, and the control valve further includes a movement regulating portion configured to regulate movement of the spacer portion toward the poppet portion.

[Object] To provide a compact, rationally designed, dual 4-port electromagnetic valve that is an electromagnetic valve having functions of two 4-port valves.

[Solution] A dual 4-port electromagnetic valve includes two spools (8a, 8b) slidable independently of each other in a valve hole (7); two pilot valves (4a, 4b) that drive the two spools, respectively; a main supply port (P) that communicates with the valve hole (7) at a position where the two spools face each other; first and second output ports (A1, A2) that communicate with the valve hole (7) on two respective sides of the main supply port (P), first and second discharge ports (E1, E2) that communicate with the valve hole (7) on two respective outer sides of the output ports (A1, A2), third and fourth output ports (B1, B2) that communicate with the valve hole (7) on two respective outer sides of the discharge ports (E1, E2), and first and second supply ports (P1, P2) that communicate with the valve hole (7) on two respective outer sides of the output ports (B1, B2). The main supply port (P) and each of the first and second supply ports (P1, P2) communicate with each other.

[Object] To provide a compact, rationally designed, dual 4-port electromagnetic valve that is an electromagnetic valve having functions of two 4-port valves.

[Solution] A dual 4-port electromagnetic valve includes two spools (8a, 8b) slidable independently of each other in a valve hole (7); two pilot valves (4a, 4b) that drive the two spools, respectively; a main supply port (P) that communicates with the valve hole (7) at a position where the two spools face each other; first and second output ports (A1, A2) that communicate with the valve hole (7) on two respective sides of the main supply port (P), first and second discharge ports (E1, E2) that communicate with the valve hole (7) on two respective outer sides of the output ports (A1, A2), third and fourth output ports (B1, B2) that communicate with the valve hole (7) on two respective outer sides of the discharge ports (E1, E2), and first and second supply ports (P1, P2) that communicate with the valve hole (7) on two respective outer sides of the output ports (B1, B2). The main supply port (P) and each of the first and second supply ports (P1, P2) communicate with each other.

A valve sleeve 210 includes an input port P10, an output port P21 connected to a channel for output T2, a discharge port P30 and a lead-in port P22 which is disposed to be connected to the channel for output T2. A spool 220 is provided with a second land section 224 that blocks a portion between the spool 220 and the valve sleeve 210 at a position between the output port P21 and the lead-in port P22 when the spool 220 is located in a position for connecting the channel for input T1 and the channel for output T2 and blocking a channel leading from the channel for output T2 to the channel for discharge T3, and when the spool 220 is located in a position for connecting the channel for output T2 and the channel for discharge T3 and blocking a channel leading from the channel for input T1 to the channel for output T2.