Abstract: A solenoid valve has a coil spring that biases a spool valve toward a solenoid portion, and an adjuster screw that is positioned to interpose the coil spring between the adjuster screw and the spool valve and that is screwed in an internally threaded portion of a sleeve so that its axial position is adjusted. The sleeve is swaged with a swaging tool etc. from an outer peripheral surface located on the outer peripheral side of the internally threaded portion of the sleeve, whereby the swaged part of the internally threaded portion is plastically deformed to the opposite side from the coil spring. The adjuster screw is thus fixed.

Abstract: A solenoid valve includes: a sleeve having a supply port and an output port; a spool valve that is housed in a valve hole formed in the sleeve so as to be movable in the axial direction, and that changes a flow passage area between the supply port and the output port by moving in the axial direction; a solenoid portion that pushes the spool valve toward one axial side; and a coil spring that urges the spool valve toward the solenoid portion. A housing hole that is a bottomed hole is formed in the spool valve, and a columnar piston member is slidably housed in the housing hole. The spool valve has an introduction hole through which a pressure of the hydraulic fluid output from the output port is introduced into a space between a bottom face of the housing hole and one end face of the piston member.

Abstract: A solenoid valve has a coil spring that biases a spool valve toward a solenoid portion, and an adjuster screw that is positioned to interpose the coil spring between the adjuster screw and the spool valve and that is screwed in an internally threaded portion of a sleeve so that its axial position is adjusted. The sleeve is swaged with a swaging tool etc. from an outer peripheral surface located on the outer peripheral side of the internally threaded portion of the sleeve, whereby the swaged part of the internally threaded portion is plastically deformed to the opposite side from the coil spring. The adjuster screw is thus fixed.

Abstract: A solenoid valve includes: a sleeve having a supply port and an output port; a spool valve that is housed in a valve hole formed in the sleeve so as to be movable in the axial direction, and that changes a flow passage area between the supply port and the output port by moving in the axial direction; a solenoid portion that pushes the spool valve toward one axial side; and a coil spring that urges the spool valve toward the solenoid portion. A housing hole that is a bottomed hole is formed in the spool valve, and a columnar piston member is slidably housed in the housing hole. The spool valve has an introduction hole through which a pressure of the hydraulic fluid output from the output port is introduced into a space between a bottom face of the housing hole and one end face of the piston member.

Abstract: In a solenoid valve 10, an annular oil groove 66 is formed at a portion corresponding to a spring chamber 56 on the external surface of a sleeve 19, a drain passage 68 is formed to make an upper part of the annular oil groove 66 communicate with the outside of an insertion bore 61, and a throttle hole 67 is provided at a lower part of the annular oil groove 66 for making the annular oil groove 66 communicate with the spring chamber 56. Since the annular oil groove 66 communicates with the outside of the insertion bore 61 at its upper part through the drain passage 68, it can be realized to store the operating oil to the height of the upper part of the annular oil groove 66, so that the operating oil can be reserved in the spring chamber 56 which communicates with the annular oil groove through the throttle hole 67. Further, the operating oil is supplied from a feedback port 48 next to the spring chamber 56 through a clearance between the spool valve 19 and a valve hole 18.

Abstract: In a solenoid valve 10, an annular oil groove 66 is formed at a portion corresponding to a spring chamber 56 on the external surface of a sleeve 19, a drain passage 68 is formed to make an upper part of the annular oil groove 66 communicate with the outside of an insertion bore 61, and a throttle hole 67 is provided at a lower part of the annular oil groove 66 for making the annular oil groove 66 communicate with the spring chamber 56. Since the annular oil groove 66 communicates with the outside of the insertion bore 61 at its upper part through the drain passage 68, it can be realized to store the operating oil to the height of the upper part of the annular oil groove 66, so that the operating oil can be reserved in the spring chamber 56 which communicates with the annular oil groove through the throttle hole 67. Further, the operating oil is supplied from a feedback port 48 next to the spring chamber 56 through a clearance between the spool valve 19 and a valve hole 18.

Abstract: Disclosed is a solenoid-operated valve which is capable of enhancing the responsivety of a device while an electric current applied thereto is in a low current range, and which is capable of preventing the device from vibrated by the fluid pressure fluctuation while in a high current range. A spool is received in a valve sleeve for regulating the pressure of fluid. A plunger is received in a stator that has a core provided with an annular projecting portion. A solenoid magnetizes the stator to attract the plunger so as to move the plunger into the annular projecting portion. The annular projecting portion is formed with a tapered portion and a thin cylindrical portion projecting from the rear end of the tapered portion. A step is formed on the outside of the annular projecting portion between the tapered portion and the thin cylindrical portion.

Abstract: An electromagnetic drive device for lineally reciprocatilvely moving an operating member like a spool of a spool valve is reduced in the manufacturing cost without being degraded in its operational performance. In the electromagnetic drive device, a stator body is excited by an electromagnetic coil to axially move a plunger guided in an inner bore of the stator body, against the resilient force of a spring. The stator body is constituted by arranging a plurality of core portion annular plate elements made of a magnetic material, a plurality of yoke portion annular plate elements made of a magnetic material and a plurality of non-magnetic portion annular plate elements made of a non-magnetic material and placed between the core portion annular plate elements and the yoke portion annular plate elements and by piling up and bodily joining these annular plate elements in axial alignment with one another.

Abstract: An electromagnetic drive device for lineally reciprocatilvely moving an operating member like a spool of a spool valve is reduced in the manufacturing cost without being degraded in its operational performance. In the electromagnetic drive device, a stator body is excited by an electromagnetic coil to axially move a plunger guided in an inner bore of the stator body, against the resilient force of a spring. The stator body is constituted by arranging a plurality of core portion annular plate elements made of a magnetic material, a plurality of yoke portion annular plate elements made of a magnetic material and a plurality of non-magnetic portion annular plate elements made of a non-magnetic material and placed between the core portion annular plate elements and the yoke portion annular plate elements and by piling up and bodily joining these annular plate elements in axial alignment with one another.