JP2013108262A - Rail bond falling-off preventing tool - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a rail bond falling-off prevention tool which prevents falling-off of a rail bond from a rail by pressing a terminal of the rail bond with an approximately constant force.SOLUTION: A rail bond falling-off prevention tool 1 is for preventing falling-off of a rail bond from a rail 2. The rail bond falling-off prevention tool 1 includes: a leaf spring 4 which comes into contact with a terminal 3 of the rail bond to press the terminal 3 to a rail web 22; and a fixing part 5 which fixes a base end 41 of the leaf spring 4 to a rail bottom 23. As the leaf spring 4 presses the terminal 3 of the rail bond, the terminal 3 is pressed to the rail web 22 with an approximately constant elastic force.

Description

  The present invention relates to a rail bond drop-off preventing device for preventing rail bond drop-off in a railway.

  Rails of railroads are electrically connected by rail bonds so that a return current and a signal current flow. The rail bond is a linear conductor and has terminals for joining to the rail at both ends of the annealed copper wire. The rail bond terminal is joined to the rail abdomen by brazing (see, for example, Patent Document 1). The rail bond may be broken due to fatigue cracks at the joint with the rail due to rail vibration or the like accompanying the running of the railway vehicle, and may fall off the rail.

  Conventionally, a rail bond drop prevention tool for preventing rail bond drop is known. As shown in FIG. 6, the rail bond drop-off prevention device 100 presses the rail bond terminal 3 against the rail abdomen 22 with a presser bolt 104. The presser bolt 104 is supported by a metal support plate 105. The support plate 105 is fixed to the rail bottom 23 at the base end side. The pressing force by the presser bolt 104 is increased by turning the presser bolt 104 in the tightening direction, and it is difficult to set an appropriate value.

  When the presser bolt 104 is tightened, the presser bolt 104 advances toward the rail abdomen 22, so that the support plate 105 bends in a direction away from the rail abdomen 22 (arrow X direction) by a reaction force. If the presser bolt 104 is tightened too much, the support plate 105 may be damaged by bending stress.

JP 2011-16145 A

  This invention solves the said problem, and it aims at providing the rail bond drop-off prevention tool which prevents the drop-off from a rail by pressing the terminal of a rail bond with substantially constant force.

  The rail bond drop-off preventing device of the present invention prevents the rail bond from falling off the rail, and contacts the rail bond terminal to press the terminal against the rail abdomen, and the base of the plate spring. And a fixing portion for fixing the end portion to the bottom of the rail.

  In this rail bond drop-off prevention device, the fixing portion includes a holding plate that clamps a base end portion of the leaf spring between the rail bottom portion and a hook that is inserted into the leaf spring and the holding plate and engages with the rail bottom portion. It is preferable to have a bolt and a nut that is screwed to the hook bolt and fastens the holding plate.

  In this rail bond drop-off preventing device, it is preferable that the leaf spring has irregularities formed on the contact surface with the rail bond terminal.

  In this rail bond fall-off preventing tool, the unevenness formed on the leaf spring is preferably a file.

  According to the rail bond drop-off preventing device of the present invention, since the leaf spring presses the rail bond terminal, the terminal is pressed against the rail abdomen by a substantially constant elastic force. Even if a crack or the like occurs in the joint between the terminal and the rail and the joining force is reduced, the terminal is held by the pressing force from the leaf spring, so that it is prevented from falling off the rail.

The side view of the rail bond fall-off prevention tool which concerns on embodiment of this invention. The top view of the rail bond fall-off prevention tool. The front view of the rail bond fall-off prevention tool. The figure which looked at the leaf | plate spring in the rail bond drop-off prevention tool from the rail side. (A) (b) (c) is the figure which looked at the modification of the leaf | plate spring in the rail bond drop-off prevention tool from the rail side. The side view of the conventional rail bond drop-off prevention tool.

  A rail bond drop-off preventing device according to an embodiment of the present invention will be described with reference to FIGS. As shown in FIGS. 1 to 3, the rail bond drop-off preventing device 1 prevents the rail bond from dropping off from the rail 2. The rail 2 includes a rail head 21, a rail abdomen 22, and a rail bottom 23. The rail bond is a linear conductor and has terminals 3 at both ends. The terminal 3 is joined to the rail abdomen 22 by brazing. The rail bond drop-off preventing device 1 includes a leaf spring 4 and a fixing portion 5. The fixing portion 5 fixes the base end portion 41 of the leaf spring 4 to the rail bottom portion 23. In a state where the base end portion 41 is fixed to the rail bottom 23, the leaf spring 4 contacts the rail bond terminal 3 and presses the terminal 3 against the rail abdomen 22 by elastic force.

  The leaf spring 4 is a metal plate and has elasticity, and the base end portion 41 is formed into a shape corresponding to one end of the rail bottom portion 23. The fixing portion 5 includes a presser plate 51, a hook bolt 52, and a nut 53. The presser plate 51 is a steel member formed in a shape corresponding to the base end portion 41 of the plate spring 4, and sandwiches the base end portion 41 of the plate spring 4 between the rail bottom portion 23. The hook bolt 52 is a bolt whose tip is shaped like a bowl, and is inserted into a bolt hole opened in the base end portion 41 of the leaf spring 4 and the presser plate 51. The hook-shaped portion of the hook bolt 52 is engaged with the other end of the rail bottom 23. The nut 53 is screwed into the hook bolt 52 to tighten the presser plate 51. The presser plate 51, the leaf spring 4, and the rail bottom 23 are fastened together by hook bolts 52 and nuts 53.

  As shown in FIG. 4, the leaf spring 4 has an uneven surface 42 formed on the contact surface with the rail bond terminal 3. In this embodiment, the unevenness 42 formed on the leaf spring 4 is a file and is a demon (woodwork) having a number of protrusions. In FIG. 4, the leaf spring 4 is not shown except in the vicinity of the portion in contact with the rail bond terminal 3 (the same applies to FIG. 5).

  As shown in FIG. 5A, the unevenness 42 formed on the leaf spring 4 may be a double file having a plurality of intersecting grooves. The roughness of this file is rough. As shown in FIG. 5B, the unevenness 42 may be a fine line in which the interval between grooves in the double line is narrowed. The roughness of the file may be an intermediate mesh between coarse and fine or an oil finer than the fine. The unevenness 42 is not limited to a file, and may have, for example, a plurality of columnar small protrusions as shown in FIG. The small protrusions are formed on the surface of the leaf spring 4 by pressing.

  According to the rail bond drop-off preventing device 1 configured as described above, since the leaf spring 4 presses the rail bond terminal 3, the terminal 3 is pressed against the rail abdomen 22 by a substantially constant elastic force (FIG. 1). reference). Even if a crack or the like occurs in the joint portion between the terminal 3 and the rail 2 and the joining force is reduced, the terminal 3 is held by the pressing force from the leaf spring 4, so that the terminal 3 is prevented from falling off. Since the rail bond is prevented from falling off, an electrical connection state by the rail bond is ensured. In addition, since a rail bond is test | inspected regularly, the crack etc. of the junction part of the terminal 3 and the rail 2 are found by inspection, and are repaired.

  The tightening force of the nut 53 acts to fix the base end portion 41 of the leaf spring 4 to the rail bottom 23 and does not generate bending stress in the leaf spring 4, so that even if the nut 53 is tightened firmly, the leaf spring 4 Will not be damaged.

  The leaf spring 4 has an increased frictional force with the terminal 3 due to the unevenness 42 formed on the contact surface of the rail bond with the terminal 3. For this reason, even if the joint portion with the rail 2 is broken, the terminal 3 is retained by the frictional force between the leaf spring 4 and the terminal 3 is prevented from falling off the rail 2. In addition, the fracture | rupture of the junction part of the terminal 3 and the rail 2 is found by inspection of a rail bond, and is repaired.

  By making the unevenness 42 formed on the leaf spring 4 a file, the effect of increasing the frictional force with the terminal 3 is enhanced.

  A rail bond drop-off preventing device 1 as an example of the present invention was manufactured and tested.

  As Example 1, the rail bond drop-off preventing device 1 shown in FIGS. 1 to 4 was manufactured. The plate spring 4 was formed by forming a stainless steel plate (JIS standard SUS304) having a plate thickness of 3 mm, the width of the portion contacting the rail bond terminal 3 was 20 mm, and the width of the base end portion 41 was 30 mm. On the contact surface of the leaf spring 4 with the terminal 3, a demon (woodwork) file was formed as irregularities 42.

  The rail bond fall-off prevention tool 1 was attached to the rail 2. A simulated bond (not shown) was sandwiched between the rail abdomen 22 and the leaf spring 4. The simulated bond simulates the rail bond terminal 3 and is a metal triangular prism.

  As a test, a hook made of a spring was hooked on the upper part of the simulated bond and pulled downward, and the tensile force when the simulated bond was displaced was measured. The measured value was 17 kgf (167 N) or more, and it was confirmed that sufficient frictional force was obtained.

  The rail bond drop-off preventing device of the second embodiment is the same as the first embodiment except that a rough double file shown in FIG. 5A is formed on the contact surface of the leaf spring 4 with the terminal 3. 1 was made. About the manufactured rail bond fall-off prevention tool 1, when the same test as Example 1 was performed and the tensile force when the imitation bond shifted | deviated was measured, the measured value was 17 kgf (167N) or more.

  The rail bond drop-off preventing device 1 of Example 3 is the same as Example 1 except that a thin double-meshed surface shown in FIG. 5B is formed on the contact surface of the leaf spring 4 with the terminal 3. Was made. About the manufactured rail bond fall-off prevention tool 1, when the same test as Example 1 was performed and the tensile force when the imitation bond shifted | deviated was measured, the measured value was 17 kgf (167N) or more.

  The rail bond dropout of Example 4 is the same as Example 1 except that a plurality of cylindrical small protrusions shown in FIG. 5C are formed on the contact surface of the leaf spring 4 with the terminal 3 by pressing. The prevention tool 1 was manufactured. About the manufactured rail bond fall-off prevention tool 1, when the same test as Example 1 was performed and the tensile force when the imitation bond shifted | deviated was measured, the measured value was 15 kgf (147N).

  The rail bond drop-off preventing device 1 of Example 5 was manufactured in the same manner as in Example 1 except that the contact surface with the terminal 3 of the leaf spring 4 was flattened without forming irregularities. About the manufactured rail bond fall-off prevention tool 1, when the same test as Example 1 was performed and the tensile force when the imitation bond shifted | deviated was measured, the measured value was 7 kgf (69N).

  As a result of the above test, it was confirmed that the friction force between the leaf spring 4 and the terminal 3 was increased by the unevenness 42 formed on the contact surface with the terminal 3 of the rail bond. It was also confirmed that the effect of increasing the frictional force with the terminal 3 was high by making the irregularities 42 filed.

  In addition, this invention is not restricted to the structure of said embodiment, A various deformation | transformation is possible in the range which does not change the summary of invention. For example, the unevenness 42 may be formed on the surface of the leaf spring 4 by a satin finish.

DESCRIPTION OF SYMBOLS 1 Rail bond drop prevention tool 4 Leaf spring 41 Base end part 42 Concavity and convexity 5 Fixing part 51 Holding plate 52 Hook bolt 53 Nut

Claims (4)

A rail bond fall-off prevention tool that prevents the rail bond from falling off the rail,
A leaf spring that contacts the rail bond terminal and presses the terminal against the rail abdomen,
A rail bond drop-off preventing device comprising: a fixing portion that fixes a base end portion of the leaf spring to a rail bottom portion. The fixing part is
A holding plate for holding the base end of the leaf spring between the bottom of the rail,
A hook bolt inserted into the leaf spring and the presser plate and hooked to the bottom of the rail;
The rail bond drop-off prevention tool according to claim 1, further comprising a nut that is screwed into the hook bolt to tighten the presser plate.   3. The rail bond drop-off prevention device according to claim 1, wherein the leaf spring has an uneven surface on a contact surface with a rail bond terminal. The rail bond drop-off prevention tool according to claim 3, wherein the unevenness formed on the leaf spring is a file.

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