Abstract: A preparation method of a test piece 100 with respect to an axle beam bush formed of metal and rubber with different material properties includes: setting a predetermined region S, so that a surface area of a portion exposed to a heat source at a predetermined position and having a lowest flame resistance is maximized in an actual use state of the axle beam bush; calculating the surface area ratio of each member in the region; and preparing the test piece 100 by using a metal member 103 and a rubber member 104 as materials same as respective members in the region, so that the metal member 103 and the rubber member 104 are exposed at ratios same as the calculated surface area ratios.

Abstract: Achieved is a rubber bushing for railroad trucks which has a novel structure and is capable of improving, for example, flame resistance to externally applied fire or the like without greatly degrading the basic properties demanded with respect to vibrational and load inputs. A rubber bushing 10 used for railroad car trucks comprises a shaft-like inner member 12 and an outer member 14, disposed on the outer peripheral side of the inner member 12 at a remove therefrom, which are linked by a rubber elastic body 16. A cover part 48 that covers an exposed end surface 44, from the outside thereof, where the rubber elastic body 16 is exposed to the outside between the axial ends of the inner member 12 and the outer member 14, is provided at an axial end of the rubber elastic body 16 as a separate member from the rubber elastic body 16.

Abstract: A load measuring device for a railcar bogie in which a vibrationproof rubber between an axle box and a bogie frame includes a vertical load fluctuation sensor in parallel with the vibrationproof rubber and configured to deform in conjunction with elastic deformation of the vibrationproof rubber in a vertical direction, the vibrationproof rubber supporting a downward load from the bogie frame. The vertical load fluctuation sensor changes an electric output by the deformation of the vertical load fluctuation sensor in conjunction with the elastic deformation of the vibrationproof rubber in the vertical direction.

Abstract: A tubular elastic linkage device for axle beam for elastically linking a truck frame and an axle beam including: an inner axial member; two outer segments opposed in axis-perpendicular direction peripherally outside the inner axial member for attachment to a housing part on an axle-beam side; and a main rubber elastic body elastically connecting them. A pocket part opens in an outer peripheral face of the main rubber elastic body onto outside via a window penetrating one outer segment. A stopper supported by the inner axial member is disposed in the pocket part to face the housing part distantly via the window. Contact of the stopper with the housing part constitutes a displacement limitation mechanism between the inner axial member and the outer segments. The other outer segment has an aperture having the main rubber elastic body exposed outside via it.

Abstract: A tubular elastic linkage device for axle beam for elastically linking a truck frame and an axle beam including: an inner axial member; two outer segments opposed in axis-perpendicular direction peripherally outside the inner axial member for attachment to a housing part on an axle-beam side; and a main rubber elastic body elastically connecting them. A pocket part opens in an outer peripheral face of the main rubber elastic body onto outside via a window penetrating one outer segment. A stopper supported by the inner axial member is disposed in the pocket part to face the housing part distantly via the window. Contact of the stopper with the housing part constitutes a displacement limitation mechanism between the inner axial member and the outer segments. The other outer segment has an aperture having the main rubber elastic body exposed outside via it.

Abstract: A load measuring device for a railcar bogie in which a vibrationproof rubber between an axle box and a bogie frame includes a vertical load fluctuation sensor in parallel with the vibrationproof rubber and configured to deform in conjunction with elastic deformation of the vibrationproof rubber in a vertical direction, the vibrationproof rubber supporting a downward load from the bogie frame. The vertical load fluctuation sensor changes an electric output by the deformation of the vertical load fluctuation sensor in conjunction with the elastic deformation of the vibrationproof rubber in the vertical direction.