Abstract: An ultrasonic flaw detector for a composite material constituted by a plurality of materials which are different in physical properties from one another includes: a section specifier configured to specify first and second sections of an RF signal of a reflected wave of an ultrasonic wave with which the composite material is irradiated, a material reflected wave being possibly generated in the first section, an interface reflected wave being possibly generated in the second section; a material flaw determiner configured to determine whether or not a value of the RF signal exceeds a positive first threshold in the first section; and an interface flaw determiner configured to determine whether or not the value of the RF signal falls below a negative second threshold in the second section.

Abstract: A railcar bogie includes: a protection target member of the railcar bogie; and a protective film including an adhesive surface stuck to the protection target member. The protective film is configured such that an impact absorbing layer and a flame-retardant layer are laminated in this order from the protection target member side. The impact absorbing layer is thicker than the flame-retardant layer.

Abstract: A state monitoring device for a plate spring mounted on a railcar bogie is configured to monitor a state of the plate spring, the plate spring including fiber-reinforced resin containing electrically conductive reinforced fibers containing reinforced fibers extending in a longitudinal direction of the plate spring. The state monitoring device includes: an electrode pair provided at both width direction side end surfaces of the plate spring and sandwiching the plate spring, a width direction of the plate spring being perpendicular to the longitudinal direction of the plate spring and a thickness direction of the plate spring; and a measuring unit electrically connected to the electrode pair and configured to measure an electrical characteristic of the plate spring.

Abstract: A railcar steering bogie includes a bogie frame, a wheelset, an axle box suspension, a steering mechanism configured to steer the wheelset, a brake unit, and a brake unit support link. The brake unit includes: a main body frame; a brake shoe supported by the main body frame and pressed against a wheel tread of the wheel during braking. The brake unit support link couples the axle box suspension and the brake unit and transmits displacement of the axle box in a car longitudinal direction to the brake unit at least during steering performed by the steering mechanism. The brake unit support link restricts the brake unit from being displaced outward in a car width direction by a predetermined distance or more during the braking. At least one of a side surface of the brake unit support link and a side surface of the brake unit includes a sliding surface.

Abstract: A railcar steering bogie includes: a bogie frame including a cross beam; pair of axles; axle boxes accommodating bearings; axle box suspensions each including a coupling member coupling the corresponding axle box and bogie frame while allowing relative displacement in a car longitudinal direction; plate spring extending in the car longitudinal direction and including car longitudinal direction end portions extending obliquely upward along the car longitudinal direction and supported above the respective axle boxes and a car longitudinal direction middle portion unfixedly arranged under the cross beam; support seats including respective inclined upper surfaces and supporting the both respective longitudinal direction end portions of the plate spring; and gap bodies each provided between an upper surface of the corresponding axle box suspension and a lower surface of the corresponding support seat and configured to allow displacement of the axle box suspension and the support seat in the car longitudinal direct

Abstract: A railcar steering bogie includes: a bogie frame supporting a bolster such that the bolster is swingable relative to bogie frame about a vertical axis; two wheelsets; axle box suspensions including respective axle beams coupling corresponding axle boxes to bogie frame, the axle boxes accommodating respective bearings supporting corresponding axles; and a steering mechanism steering at least one of the two wheelsets in accordance with the bolster's swinging relative to the bogie frame. The steering mechanism includes: a steering lever configured to turn relative to the bogie frame about fulcrum axis; a coupling link coupling the bolster and steering lever and configured to operate in conjunction with the bolster's swinging relative to the bogie frame; and at least one steering link coupling steering lever and axle beam and configured to steer the corresponding wheelset by displacing corresponding axle box through the corresponding axle beam in conjunction with steering lever's turning.

Abstract: A railcar steering bogie includes: a bogie frame supporting a bolster such that the bolster is swingable relative to the bogie frame about a vertical axis; two wheelsets each including an axle and a pair of wheels; and a steering mechanism configured to steer at least one of the two wheelsets in accordance with the swinging of the bolster relative to the bogie frame. The steering mechanism includes: a steering lever configured to turn relative to the bogie frame about a fulcrum axis; a coupling link coupling the bolster and the steering lever and configured to operate in conjunction with the swinging of the bolster relative to the bogie frame; and a steering link coupled to the steering lever and configured to steer the wheelset in conjunction with the turning of the steering lever. The steering link is coupled to the steering lever by a pin member.

Abstract: A plate spring unit applied to a railcar bogie includes: a lower plate spring including both longitudinal direction end portions supported by the respective axle boxes from below, the lower plate spring being made of fiber-reinforced resin; an upper plate spring arranged above the lower plate spring with a gap and including a middle portion pressed from above by a pressing member provided at the cross beam, the upper plate spring being made of fiber-reinforced resin; a middle spacer sandwiched between a middle portion of the lower plate spring and the middle portion of the upper plate spring; and an end spacer sandwiched between the end portion of the lower plate spring and an end portion of the upper plate spring and allowing relative displacement between the end portion of the lower plate spring and the end portion of the upper plate spring in a longitudinal direction.

Abstract: A method of producing an electrode-equipped plate spring of a railcar bogie includes: a resin removing step of partially irradiating a surface of fiber-reinforced resin, prepared by including electrically conductive fibers in resin, of a plate spring with a laser beam to partially remove the resin and partially expose the electrically conductive fibers; and an electrode forming step of attaching an electrode to an exposed region formed by partially exposing the electrically conductive fibers of the fiber-reinforced resin.

Abstract: An axle box suspension includes: an axle beam including an axle beam main body portion extending from the axle box in a car longitudinal direction and a pin portion projecting from a tip end of the axle beam main body portion in the car longitudinal direction; a tubular elastic bushing including an inner tube portion, an outer tube portion, and an elastic portion interposed between the inner tube portion and the outer tube portion, the inner tube portion being fitted to the pin portion; an adapter attached to the outer tube portion and coupling the axle beam and the bogie frame; and a first stopper attached to the pin portion and configured to, when the axle box is displaced relative to the bogie frame toward one side in the car longitudinal direction by a predetermined distance, contact the adapter to restrict displacement of the axle box.

Abstract: A railcar bogie includes: a protection target member of the railcar bogie; and a protective film including an adhesive surface stuck to the protection target member. The protective film is configured such that an impact absorbing layer and a flame-retardant layer are laminated in this order from the protection target member side. The impact absorbing layer is thicker than the flame-retardant layer.

Abstract: An ultrasonic flaw detector for a composite material constituted by a plurality of materials which are different in physical properties from one another includes: a section specifier configured to specify first and second sections of an RF signal of a reflected wave of an ultrasonic wave with which the composite material is irradiated, a material reflected wave being possibly generated in the first section, an interface reflected wave being possibly generated in the second section; a material flaw determiner configured to determine whether or not a value of the RF signal exceeds a positive first threshold in the first section; and an interface flaw determiner configured to determine whether or not the value of the RF signal falls below a negative second threshold in the second section.

Abstract: A method of producing plate springs for a railcar bogie, the plate springs each extending in a car longitudinal direction and elastically supporting a cross beam while being supported by an axle box in the railcar bogie, the axle box accommodating a bearing for an axle, the method includes: a molding step of molding a mother plate made of fiber-reinforced resin, the mother plate including a layer made of continuous fibers oriented in a first direction when viewed from a normal direction of a main surface of the mother plate; a cut position determining step of determining positions of a plurality of parallel cut lines for cutting the mother plate along the first direction; and a cutting step of cutting the mother plate along the plurality of cut lines to take out the plate springs made of the fiber-reinforced resin.

Abstract: A railcar steering bogie includes a bogie frame, a wheelset, an axle box suspension, a steering mechanism configured to steer the wheelset, a brake unit, and a brake unit support link. The brake unit includes: a main body frame; a brake shoe supported by the main body frame and pressed against a wheel tread of the wheel during braking. The brake unit support link couples the axle box suspension and the brake unit and transmits displacement of the axle box in a car longitudinal direction to the brake unit at least during steering performed by the steering mechanism. The brake unit support link restricts the brake unit from being displaced outward in a car width direction by a predetermined distance or more during the braking. At least one of a side surface of the brake unit support link and a side surface of the brake unit includes a sliding surface.

Abstract: A railcar steering bogie includes: a bogie frame including a cross beam; pair of axles; axle boxes accommodating bearings; axle box suspensions each including a coupling member coupling the corresponding axle box and bogie frame while allowing relative displacement in a car longitudinal direction; plate spring extending in the car longitudinal direction and including car longitudinal direction end portions extending obliquely upward along the car longitudinal direction and supported above the respective axle boxes and a car longitudinal direction middle portion unfixedly arranged under the cross beam; support seats including respective inclined upper surfaces and supporting the both respective longitudinal direction end portions of the plate spring; and gap bodies each provided between an upper surface of the corresponding axle box suspension and a lower surface of the corresponding support seat and configured to allow displacement of the axle box suspension and the support seat in the car longitudinal direct

Abstract: A railcar steering bogie includes: a bogie frame supporting a bolster such that the bolster is swingable relative to the bogie frame about a vertical axis; two wheelsets each including an axle and a pair of wheels; and a steering mechanism configured to steer at least one of the two wheelsets in accordance with the swinging of the bolster relative to the bogie frame. The steering mechanism includes: a steering lever configured to turn relative to the bogie frame about a fulcrum axis; a coupling link coupling the bolster and the steering lever and configured to operate in conjunction with the swinging of the bolster relative to the bogie frame; and a steering link coupled to the steering lever and configured to steer the wheelset in conjunction with the turning of the steering lever. The steering link is coupled to the steering lever by a pin member.

Abstract: A railcar steering bogie includes: a bogie frame supporting a bolster such that the bolster is swingable relative to bogie frame about a vertical axis; two wheelsets; axle box suspensions including respective axle beams coupling corresponding axle boxes to bogie frame, the axle boxes accommodating respective bearings supporting corresponding axles; and a steering mechanism steering at least one of the two wheelsets in accordance with the bolster's swinging relative to the bogie frame. The steering mechanism includes: a steering lever configured to turn relative to the bogie frame about fulcrum axis; a coupling link coupling the bolster and steering lever and configured to operate in conjunction with the bolster's swinging relative to the bogie frame; and at least one steering link coupling steering lever and axle beam and configured to steer the corresponding wheelset by displacing corresponding axle box through the corresponding axle beam in conjunction with steering lever's turning.

Abstract: An axle box suspension includes: an axle beam including an axle beam main body portion extending from the axle box in a car longitudinal direction and a pin portion projecting from a tip end of the axle beam main body portion in the car longitudinal direction; a tubular elastic bushing including an inner tube portion, an outer tube portion, and an elastic portion interposed between the inner tube portion and the outer tube portion, the inner tube portion being fitted to the pin portion; an adapter attached to the outer tube portion and coupling the axle beam and the bogie frame; and a first stopper attached to the pin portion and configured to, when the axle box is displaced relative to the bogie frame toward one side in the car longitudinal direction by a predetermined distance, contact the adapter to restrict displacement of the axle box.

Abstract: A method of producing an electrode-equipped plate spring of a railcar bogie includes: a resin removing step of partially irradiating a surface of fiber-reinforced resin, prepared by including electrically conductive fibers in resin, of a plate spring with a laser beam to partially remove the resin and partially expose the electrically conductive fibers; and an electrode forming step of attaching an electrode to an exposed region formed by partially exposing the electrically conductive fibers of the fiber-reinforced resin.

Abstract: A plate spring unit applied to a railcar bogie includes: a lower plate spring including both longitudinal direction end portions supported by the respective axle boxes from below, the lower plate spring being made of fiber-reinforced resin; an upper plate spring arranged above the lower plate spring with a gap and including a middle portion pressed from above by a pressing member provided at the cross beam, the upper plate spring being made of fiber-reinforced resin; a middle spacer sandwiched between a middle portion of the lower plate spring and the middle portion of the upper plate spring; and an end spacer sandwiched between the end portion of the lower plate spring and an end portion of the upper plate spring and allowing relative displacement between the end portion of the lower plate spring and the end portion of the upper plate spring in a longitudinal direction.