Abstract: A transmission line 5 configured to be broken when it comes into contact with a rail 4 is installed on a disengagement prevention guide 1 attached to an axle box 3 of a railway vehicle. One end 5a and the other end 5b of the transmission line 5 are connected to a determination unit 6 to monitor continuity of the transmission line 5. In the event of a derailment, the determination unit 6 determines that a derailment has occurred when the disengagement prevention guide 1 makes contact with the rail 4 and the transmission line 5 breaks, thereby interrupting the continuity of the transmission line 5. This arrangement allows an accurate detection of a derailment, so as to prevent a railway vehicle from traveling when its wheels have become disengaged from a rail without an operator being aware of it, thus improving safety after the derailment occurs.

Abstract: A transmission line 5 configured to be broken when it comes into contact with a rail 4 is installed on a disengagement prevention guide 1 attached to an axle box 3 of a railway vehicle. One end 5a and the other end 5b of the transmission line 5 are connected to a determination unit 6 to monitor continuity of the transmission line 5. In the event of a derailment, the determination unit 6 determines that a derailment has occurred when the disengagement prevention guide 1 makes contact with the rail 4 and the transmission line 5 breaks, thereby interrupting the continuity of the transmission line 5. This arrangement allows an accurate detection of a derailment, so as to prevent a railway vehicle from traveling when its wheels have become disengaged from a rail without an operator being aware of it, thus improving safety after the derailment occurs.

Abstract: The object is to solve the issue of an over-steered state at an exit straight portion in addition to enhance a curve passage performance than when a steering angle of front and rear axles is set at a radial steering angle. A steering method for a steering device intentionally turns two axles (12a, 12b) of a truck (12) of a railway vehicle relative to a frame of the truck. The two axles are arranged at front and rear of the truck with respect to a direction of running of the railway vehicle. The steering method includes steering the axles such that a steering angle (?1) of the front axle (12a) is larger than a steering angle (?2) of the rear axle (12b).

Abstract: A bogie frame for railway vehicles includes a pair of left and right side beams disposed along a direction of rails; a cross beam that connects the side beams to each other, and a mounting bracket for mounting a functional part, the mounting bracket being joined to the cross beam. The cross beam has a rectangular cross section and includes a top plate section, a bottom plate section, and a pair of side plate sections. The top plate section has a cutout opening extending to one of the side plate sections. The mounting bracket is inserted in the cutout opening and the mounting bracket and the top plate section are butt welded together. This configuration enhances welding workability for welding mounting brackets for mounting functional parts such as a traction motor, a gearbox, and a brake, and allows a greater degree of design flexibility in mounting the functional parts.

Abstract: A bogie frame for railway vehicles includes a pair of left and right side beams disposed along a direction of rails; a cross beam that connects the side beams to each other, and a mounting bracket for mounting a functional part, the mounting bracket being joined to the cross beam. The cross beam has a rectangular cross section and includes a top plate section, a bottom plate section, and a pair of side plate sections. The top plate section has a cutout opening extending to one of the side plate sections. The mounting bracket is inserted in the cutout opening and the mounting bracket and the top plate section are butt welded together. This configuration enhances welding workability for welding mounting brackets for mounting functional parts such as a traction motor, a gearbox, and a brake, and allows a greater degree of design flexibility in mounting the functional parts.

Abstract: The object is to solve the issue of an over-steered state at an exit straight portion in addition to enhance a curve passage performance than when a steering angle of front and rear axles is set at a radial steering angle. A steering method for a steering device intentionally turns two axles (12a, 12b) of a truck (12) of a railway vehicle relative to a frame of the truck. The two axles are arranged at front and rear of the truck with respect to a direction of running of the railway vehicle. The steering method includes steering the axles such that a steering angle (?1) of the front axle (12a) is larger than a steering angle (?2) of the rear axle (12b).

Abstract: A steerable truck for a railway car is provided with a truck frame that is steered so as to be aligned with the tangential direction of a curved track by controlling only the steering angle of a rear wheelset. During travel along a curved track, the steering angle, which is the angle in a horizontal plane of the centerline of the rear wheelset with respect to an imaginary straight line connecting the center of the truck frame and the center of the curved track, is larger than the steering angle which is the angle formed between the imaginary straight line and the centerline of the front wheelset. As a result, a steerable truck for a railway car which has excellent ability to travel along a curve and which can be actually realized simply and at a low cost is provided.

Abstract: Lateral pressure which develops in the front wheelset when traveling along a curved track is decreased while suppressing an increase in costs as much as possible. A two-axle truck for a railway car has a front wheelset having wheels with a first tread gradient and a rear wheelset having wheels with a second tread gradient which is different from the first tread gradient. The tread gradient of the wheels of the rear wheelset is larger than the tread gradient of the wheels of the front wheelset.

Abstract: Lateral pressure which develops in the front wheelset when traveling along a curved track is decreased while suppressing an increase in costs as much as possible. A two-axle truck for a railway car has a front wheelset having wheels with a first tread gradient and a rear wheelset having wheels with a second tread gradient which is different from the first tread gradient. The tread gradient of the wheels of the rear wheelset is larger than the tread gradient of the wheels of the front wheelset.

Abstract: Lateral pressure which develops in the front wheelset when traveling along a curved track is decreased while suppressing an increase in costs as much as possible. A two-axle truck for a railway car has a front wheelset having wheels with a first tread gradient and a rear wheelset having wheels with a second tread gradient which is different from the first tread gradient. The tread gradient of the wheels of the rear wheelset is larger than the tread gradient of the wheels of the front wheelset.

Abstract: Lateral pressure which develops in the front wheelset when traveling along a curved track is decreased while suppressing an increase in costs as much as possible. A two-axle truck for a railway car has a front wheelset having wheels with a first tread gradient and a rear wheelset having wheels with a second tread gradient which is different from the first tread gradient. The tread gradient of the wheels of the rear wheelset is larger than the tread gradient of the wheels of the front wheelset.

Abstract: A steerable truck for a railway car is provided with a truck frame that is steered so as to be aligned with the tangential direction of a curved track by controlling only the steering angle of a rear wheelset. During travel along a curved track, the steering angle, which is the angle in a horizontal plane of the centerline of the rear wheelset with respect to an imaginary straight line connecting the center of the truck frame and the center of the curved track, is larger than the steering angle which is the angle formed between the imaginary straight line and the centerline of the front wheelset. As a result, a steerable truck for a railway car which has excellent ability to travel along a curve and which can be actually realized simply and at a low cost is provided.