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.

A railcar bogie includes: a cross beam supporting a carbody of a railcar; an axle box including a bearing accommodating portion accommodating a bearing rotatably supporting a wheelset; a plate spring extending in a car longitudinal direction while supporting a car width direction end portion of the cross beam; and a receiving member provided above the axle box and supporting a car longitudinal direction end portion of the plate spring, an attachment hole being formed at a car longitudinal direction outside portion of the receiving member, a lifting fitting used to lift the bogie being attached to the attachment hole.

A railcar bogie includes a plate spring supported by a pair of axle boxes arranged away from each other in a car longitudinal direction, the plate spring supporting a cross beam while being pressed by a pressing member of a bogie frame from above such that the pressing member is separable from the plate spring, at least a lower surface of the plate spring containing resin. The lower surface of the plate spring includes an inclined surface inclined with respect to a horizontal direction when viewed from a car width direction. The bogie frame includes at least one lifting supporting portion, the at least one lifting supporting portion including a supporting surface, the supporting surface being opposed to the inclined surface of the plate spring from below with a gap and inclined along the inclined surface of the plate spring.

An axle box suspension includes: a coupler extending from an axle box in a car longitudinal direction and including a tubular portion at an end portion of the coupler, the tubular portion being open toward both sides in a car width direction; a core rod inserted into an internal space of the tubular portion, a pair of protruding portions being provided at both sides of the core rod in the car width direction; an elastic body interposed between the tubular portion and the core rod; a pair of receiving seats provided at the bogie frame and including a pair of groove portions which are open toward the car width direction and an upper side; a pair of lids pressing, from above, the pair of protruding portions fitted into the pair of groove portions from above; and fasteners fixing the lids to the receiving seats.

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 direction.

A railcar bogie includes a bogie frame including a cross beam and supports, the supports disposed at respective car width direction end portions of the cross beam. There are a plurality of axle boxes to accommodate a plurality of bearings supporting a pair of axles, a plate spring extending in a car longitudinal direction and supported by a pair of the axle boxes which are away from each other in the car longitudinal direction among the plurality of axle boxes. The plate spring supports the cross beam while being pressed by the corresponding support from above such that the pressing member is separable from the plate spring. Elastic walls are at both respective sides of the supports in the car longitudinal direction and sandwiched between a lower surface of the bogie frame and an upper surface of the plate spring so as to be compressed.

A railcar bogie includes a cross beam, an axle box, a supporting member, a plate spring, and an axle beam. The axle box accommodates a bearing rotatably supporting a wheelset. The supporting member is provided at an upper portion of the axle box. The plate spring supports a car width direction end portion of the cross beam and extends in a car longitudinal direction, and the plate spring includes a car longitudinal direction end portion supported by the supporting member. The axle beam couples the axle box and the cross beam in the car longitudinal direction and is opposed to the plate spring in an upward/downward direction. An installation seat is provided at an upper surface of the axle beam and includes an installation surface on which a pushing-up device configured to push up a lower surface of the plate spring can be placed.

A method of assembling a railcar bogie includes: a positioning step of locking a wheelbase fixing jig to a pair of axle box devices to position the pair of axle box devices such that a wheelbase between a pair of wheelsets supported by the respective axle box devices becomes a predetermined designed value, the pair of axle box devices being arranged away from each other in a car longitudinal direction, the wheelbase fixing jig extending in the car longitudinal direction; a plate spring arranging step of making the pair of axle box devices support a plate spring extending in the car longitudinal direction; and a bogie frame arranging step of making a longitudinal direction middle portion of the plate spring support a bogie frame and coupling the bogie frame to the pair of axle box devices.

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.

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.