Rail bond removing jig and rail bond removing device
The rail bond removal jig and device facilitate the efficient and safe removal of rail bonds by one person, addressing the inefficiencies and safety concerns of existing methods through the use of a guided chisel and electric hammer.
Patent Information
- Application Number
- JP2023188285
- Authority / Receiving Office
- JP · JP
- Patent Type
- Applications
- Current Assignee / Owner
- Filing Date
- 2023-11-02
- Publication Date
- 2025-05-16
- Estimated Expiration
- 2043-11-02
AI Technical Summary
The existing methods for removing rail bonds from rails require two people and are inefficient, leading to worker fatigue and the risk of accidents due to the need for manual hammering.
A rail bond removal jig and device that allows one person to easily remove rail bonds by using a mounting portion, guide portion, pedal, and arm portion to position and impact a chisel on the rail bond terminals, driven by an electric hammer.
The solution enables efficient and safe removal of rail bonds by one person, reducing worker fatigue and the risk of accidents, while also improving work efficiency and allowing for the use of a rail bond removal device that can be reused.
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Figure 2025076614000001_ABST
Abstract
Description
[Technical field]
[0001] The present invention relates to a rail bond removal tool for removing a rail bond from a rail, and a rail bond removal device having the tool. [Background technology]
[0002] Railway rails have joints that are electrically connected by rail bonds to allow electric current to flow (see Japanese Industrial Standard JIS E3013 "Railway Signaling Safety Terminology"). Rail bonds have terminals at both ends of the conductor for joining to the rail. The rail bond terminals are joined to the web of the rail on the outside of the track (see Patent Document 1, for example). Rail vibrations caused by the running of railway vehicles can cause fatigue cracks at the joint with the rail, leading to breakage and detachment from the rail. For this reason, rail bonds are replaced as a preventive maintenance measure.
[0003] When replacing rail bonds or exchanging rails, it is necessary to remove the rail bonds, and a task called rail bond removal is performed by a team of two workers. Since the rail bonds are strongly bonded to the rails (see, for example, Patent Document 2), rail bond removal is not easy. One worker holds a chisel and places the tip of the chisel against the rail bond terminal, while the other worker strikes the chisel with a hammer to knock the rail bond terminal off the rail. This type of work requires skill and is performed by two workers, resulting in low work efficiency. As many as 100 rail bonds may be removed in one night, the worker who swings the hammer is highly fatigued. There is also a risk of industrial accidents caused by the hammer. Furthermore, it is necessary to respond to the decrease in the working population and the aging of the workforce in the construction industry. [Prior art documents] [Patent documents]
[0004] [Patent Document 1] JP 2011-16145 A [Patent Document 2] JP 2016-107294 A Summary of the Invention [Problem to be solved by the invention]
[0005] The present invention is intended to solve the above problems and aims to provide a rail bond removal jig and rail bond removal device that allows one person to easily remove a rail bond. [Means for solving the problem]
[0006] The rail bond removal jig of the present invention is a jig for removing a rail bond from a rail, and comprises a mounting part that is detachably attached to the head of the rail, a guide part supported by the mounting part for positioning a chisel that strikes the terminal of the rail bond, a pedal that is lower than the head of the rail, higher than the bottom surface of the rail and located outside the track from the mounting part, and an arm part that supports the pedal on the mounting part, and is characterized in that the mounting part has a web, an inner flange, a hook part and an outer flange, the web is a part that is placed on the top of the rail, the inner flange is a part that extends downward from the end of the web on the inside of the track, the hook part is a part that protrudes from the lower end of the inner flange toward the body of the rail and is hooked onto the jaw part of the rail, and the outer flange is a part that extends downward from the end of the web on the outside of the track.
[0007] In this rail bond removal jig, it is preferable that the guide portion has a cylindrical portion through which the shank of the chisel is inserted, the shank of the chisel has freedom of movement in the striking direction relative to the cylindrical portion, and the inside of the cylindrical portion has a vertical width greater than its horizontal width in the longitudinal direction of the rail.
[0008] In this rail bond removal jig, it is preferable that the arm portion has a shape that avoids interference with a rail fastening device when the mounting portion is attached to the head of the rail.
[0009] The rail bond removal device of the present invention is a device for removing a rail bond from a rail, and is characterized by comprising the rail bond removal jig, a chisel for striking the terminal of the rail bond, and an electric hammer for strikingly driving the chisel. Effect of the Invention
[0010] The rail bond removal jig and rail bond removal device of the present invention are fixed to the rail by stepping on a pedal, and the chisel that strikes the rail bond terminal can be positioned using the guide section, so that a single worker can easily remove the rail bond. [Brief description of the drawings]
[0011] [Figure 1] FIG. 1 is a side view of a rail bond removal device according to one embodiment of the present invention. [Diagram 2] FIG. 2 is a plan view of the chisel of the device. [Diagram 3] FIG. 3 is a perspective view showing a state in which a rail bond removal jig according to one embodiment of the present invention is attached to a rail. [Figure 4] FIG. 4 is a side view of the jig. [Diagram 5] FIG. 5 is a plan view of the jig. [Figure 6] FIG. 6 is a front view of the jig seen from outside the track. [Figure 7] 7(a), (b), (c), and (d) are side views showing the attachment of the jig to the rail in chronological order. [Figure 8] FIG. 8(a) is a side view before the rail bond is removed by the rail bond removal device, and FIG. 8(b) is a side view after the rail bond has been removed. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS
[0012] A rail bond removal jig and rail bond removal device according to one embodiment of the present invention will be described with reference to Figures 1 to 6. A rail bond has a conductor wire (bond wire) and terminals on both ends. As shown in Figure 1, a terminal 81 of the rail bond is joined to an inner portion 91 on the outer side of the track of a rail 9 (the right side in Figure 1). The track has two rails. The inner side of the track of a rail is the side where the two rails face each other. The outer side of the track of a rail is the opposite side.
[0013] The rail bond removal device 1 is a device that removes a rail bond from a rail 9. The rail bond removal device 1 includes a rail bond removal jig 2, a chisel 11, and an electric hammer 12. The chisel 11 is a tool that strikes a terminal 81 of the rail bond. The electric hammer 12 is an electric tool that strikes and drives the chisel 11.
[0014] As shown in Fig. 2, the chisel 11 is a tool for chipping, also called a chisel, made of steel, and has a shaft 111 and a blade 112. The blade 112 is at the tip of the chisel 11, and is the part that comes into contact with the terminal 81 of the rail bond 8. In this embodiment, the chisel 11 is a flat chisel made of iron, and the width of the blade 112 is greater than the diameter of the shaft 111. The base end of the shaft 111 is attached to the electric hammer 12 by a chuck 121 of the electric hammer 12 (see Fig. 1).
[0015] The blade 112 of the chisel 11, which is a single-edged chisel with a flat lower side, leaves less wax residue on the rail 9 after the terminal 81 is removed than a double-edged chisel. The blade 112 may be a double-edged chisel. A double-edged chisel is easy to use because it does not need to distinguish between the top and bottom.
[0016] In this embodiment, the electric hammer 12 is a commercially available product. By adopting a commercially available electric hammer 12, the cost of the rail bond removal device 1 can be reduced. The electric hammer 12 is a rechargeable type having a storage battery as a power source, and there is no need to secure an external power source on-site.
[0017] Figure 3 shows the rail bond removal jig 2 attached to a rail 9. The rail bond removal jig 2 is a jig for removing the rail bond 8 from the rail 9. In the example shown in Figure 3, the conductor of the rail bond 8 can be seen on the front side of the rail bond removal jig 2.
[0018] As shown in Figures 4 to 6, the rail bond removal jig 2 comprises a mounting portion 3, a guide portion 4, a pedal 5, and an arm portion 6. The mounting portion 3 is detachably attached to the head portion 92 of the rail 9. The guide portion 4 is supported by the mounting portion 3 and is a portion for positioning a chisel 11 that strikes a terminal 81 of the rail bond. The pedal 5 is lower than the head portion 92 of the rail 9, higher than the bottom surface 93 of the rail 9, and is located outside the track of the mounting portion 3 (right side in Figure 4). The arm portion 6 supports the pedal 5 on the mounting portion 3.
[0019] The mounting portion 3 has a web 31, an inner flange 32, a hook portion 33, and an outer flange 34. The web 31 is a portion that is placed on the top portion 94 of the rail 9. The inner flange 32 is a portion that extends downward from the end portion of the web 31 on the inside of the track. The hook portion 33 is a portion that protrudes from the lower end of the inner flange 32 toward the body portion 91 of the rail 9 and is hooked onto the jaw portion 95 of the rail 9. The outer flange 34 is a portion that extends downward from the end portion of the web 31 on the outside of the track.
[0020] The guide portion 4 has a cylindrical portion 41 into which a shaft portion 111 of the chisel 11 is inserted. The shaft portion 111 of the chisel 11 has a degree of freedom in the striking direction relative to the cylindrical portion 41. The inner side of the cylindrical portion 41 has a vertical width V larger than a horizontal width W in the longitudinal direction of the rail.
[0021] The arm portion 6 has a shape that avoids interference with a rail fastening device 96 when the mounting portion 3 is attached to the head portion 92 of the rail 9 (see FIG. 3). The rail fastening device 96 is a device that fastens the rail 9 to a support such as a sleeper 97.
[0022] The configuration of the rail bond removal jig 2 will be described in further detail. The rail bond removal jig 2 is made of metal. The metal is iron or stainless steel. The mounting portion 3 has a cross-sectional shape similar to that of a channel steel, and is formed by bending a metal plate (see FIG. 4). The web 31 is flat. The inner flange 32 and the outer flange 34 face each other. The web 31 is placed on the top portion 94 of the rail 9, and the head portion 92 of the rail 9 is located between the inner flange 32 and the outer flange 34.
[0023] In this embodiment, the outer flange 34 has a protrusion 341 fixed to a surface facing the head 92 of the rail 9. The protrusion 341 reduces the gap between the head 92 of the rail 9 and the outer flange 34. The protrusion 341 may eliminate the gap between the head 92 of the rail 9 and the outer flange 34. Also, the protrusion 341 may be omitted by reducing the gap between the upper parts of the inner flange 32 and the outer flange 34.
[0024] The outer flange 34 has a notch in the center extending from the lower end to the upper end (see FIG. 3). The notch reaches a part of the web 31. The notch makes it easier to see the chisel 11 and the terminal 81 of the rail bond 8, and facilitates the positioning of the chisel 11.
[0025] The guide portion 4 has a tubular portion 41 and a support plate 42 (see FIG. 4). In this embodiment, the tubular portion 41 is a square tube (see FIG. 6). The shape of the tubular portion 41 is not limited to a square tube, and may be, for example, an upside-down U-shape in cross section. The base end side of the support plate 42 is fixed to the outer flange 34, and the tip side faces diagonally upward in side view (see FIG. 4). The tubular portion 41 is fixed to the upper surface near the upper end of the support plate 42. The chisel 11 inserted into the tubular portion 41 faces diagonally downward in side view.
[0026] The shaft 111 of the chisel 11 is narrower than the inner width W and length V of the cylindrical portion 41 and can move in the striking direction.
[0027] By reducing the inner width W of the cylindrical portion 41 of the guide portion 4, the play (gap) of the chisel 11 in the rail longitudinal direction within the cylindrical portion 41 is minimized, making it difficult for the chisel 11 to slip out of place. This allows the chisel 11 to strike the terminal 81 efficiently.
[0028] In order to bring the chisel 11 into contact with the rail bond terminal 81 at an optimal angle, the inner vertical width V of the tube portion 41 of the guide portion 4 is set so that the angle of the chisel 11 can be changed within a certain range. In this embodiment, the angle of the chisel 11 with respect to the horizontal plane can be adjusted within a range of 45° to 58° by setting the vertical width V. This makes it possible to adjust the angle of the chisel 11 and position the chisel 11 in the height direction even if there is variation in the height at which the rail bond terminal 81 is joined to the rail 9. In addition, by limiting the adjustment range of the angle of the chisel 11 with the guide portion 4, the positioning operation of the chisel 11 is stabilized and individual differences in the operation are reduced.
[0029] There are several types of rails with different cross-sectional shapes (see Japanese Industrial Standard JIS E1101 "Ordinary rails and special rails for turnouts"). For example, the commonly used 50kgN rails and 60kg rails have the same head width and head height, but different rail heights. The difference in rail height can be accommodated by setting the inner vertical width V of the tube portion 41, and the same rail bond removal jig 2 can be used for both 50kgN rails and 60kg rails.
[0030] The pedal 5 is also called the foot pedal, and is a part that is stepped on by a worker (a user of the rail bond removal jig 2) (see FIG. 3). In this embodiment, the pedal 5 and the arm portion 6 are integral, have a three-sided rectangular shape in a plan view (see FIG. 5), and are formed by bending a metal rod. The base end of the arm portion 6 is welded to the outer flange 34 (see FIG. 3). The pedal 5 is located at the tip side of the arm portion 6. The pedal 5 is a part of the metal rod that is parallel to the rail longitudinal direction. There are two arm portions 6, and they support both ends of the pedal 5. The middle portion 61 of the arm portion 6 is a portion that may be located above the rail fastening device 96, is lower than the outer flange 34, is higher than the rail fastening device 96, and extends outside the track. The pedal 5 is located at the end of the arm portion 6 outside the track.
[0031] As a modification of this embodiment, the plate-shaped outer flange 34 may be omitted, the base end of the arm portion 6 may be welded to the web 31, and the upper portion of the arm portion 6 may be used as the outer flange.
[0032] The mounting of the rail bond removal jig 2 configured as above to the rail 9 will be described with reference to Figs. 7(a), (b), (c), (d), etc. When the width of the blade 112 of the chisel 11 (see Fig. 2) is larger than the inner width W of the tube part 41 of the guide part 4 (see Fig. 5), the chisel 11 is first inserted into the tube part 41 from below, and the chisel 11 is attached to the electric hammer 12 (see Fig. 1). The rail bond removal jig 2 is in a state where it is hooked on the chisel 11. The worker moves along the rail 9, holding the electric hammer 12 on which the chisel 11 is hooked. When the worker arrives at the work site, the rail bond removal jig 2 is mounted on the rail 9. The chisel 11 and the electric hammer 12 are omitted from Figs. 7(a) to (d).
[0033] As shown in Figure 7(a), one worker stands the web 31 of the mounting part 3 at an angle and brings the hook part 33 into contact with the jaw part 95 on the inside of the track of the rail 9. At this time, the position of the rail bond removal jig 2 in the rail longitudinal direction (the direction perpendicular to the paper surface of Figure 7) is adjusted.
[0034] Then, as shown in FIG. 7( b ), when the guide portion 4 is tilted toward the outside of the track while the hook portion 33 is hooked onto the jaw portion 95 on the inside of the track of the rail 9 , the web 31 falls toward the top portion 94 of the rail 9 .
[0035] Then, as shown in FIG. 7( c ), the web 31 rests on the top portion 94 of the rail 9 .
[0036] 7(d), when the worker depresses the pedal 5 to apply a downward force (indicated by the outline arrow), the mounting part 3, arm part 6 and pedal 5 function as a second type of lever. With the pedal 5 as the force point, the hook part 33 as the fulcrum, and the underside of the web 31 as the point of action, the mounting part 3 is pressed against the head part 92 of the rail 9, and the rail bond removal jig 2 is fixed to the rail 9.
[0037] Next, removal of the rail bond by the rail bond removal device 1 will be described with reference to Figures 8(a) and (b). As shown in Figure 8(a), an operator steps on the pedal 5 and places the tip of the chisel 11 against the upper part of the terminal 81 of the rail bond. It is preferable that the chisel 11 be placed against the upper part of the terminal 81 close to the boundary with the rail 9. The chisel 11 is then driven by an electric hammer 12 to strike the terminal 81. Even if the rail bond removal jig 2 is subjected to vibrations, etc., by stepping on the pedal 5, it is possible to prevent the chisel 11 from shaking.
[0038] 8(b), the impact causes the rail bond terminal 81 to come off from the inner portion 91 of the rail 9.
[0039] Next, by releasing the pedal 5 and releasing the rail bond removal jig 2 from its attachment to the rail 9, as shown in Figures 7(d)(c)(b), the rail bond removal jig 2 can be slid and moved in the longitudinal direction of the rail.
[0040] Then, the rail bond removal jig 2 is moved to the position of the terminal 81 of the next rail bond to be removed. The attachment of the rail bond removal jig 2 to the rail 9 and the removal of the rail bond by the rail bond removal device 1 are as described above. The rail bond is removed from the rail 9 by removing the terminals 81 at both ends of the rail bond.
[0041] As described above, the rail bond removal jig 2 of this embodiment is fixed to the rail 9 by stepping on the pedal 5, and the chisel 11 that strikes the terminal 81 of the rail bond can be positioned by the guide portion 4, so that a single worker can easily remove the rail bond (see Figure 1).
[0042] The inside of the cylindrical portion 41 of the guide portion 4 has a vertical width V that is larger than the horizontal width W in the longitudinal direction of the rail. This makes it easy to position the chisel 11 in the rail longitudinal direction (direction of width W), and also makes it possible to position the chisel 11 in the height direction (direction of vertical width V) even if there is variation in the height at which the rail bond terminal 81 is joined to the rail 9.
[0043] The arm portion 6 has a shape that avoids interference with the rail fastening device 96 when the mounting portion 3 is attached to the head 92 of the rail 9 (see Figure 3), so that the rail bond removal jig 2 can be attached to the rail 9 even in the position where the rail fastening device 96 is present.
[0044] Since the rail bond removal device 1 has an electric hammer 12, there is no need to swing the hammer by hand, and no skill is required for the work, so fatigue from the work is reduced and the risk of work-related accidents is reduced (see Figure 1).
[0045] The present invention is not limited to the configuration of the above embodiment, and various modifications are possible without departing from the spirit and scope of the invention. For example, the electric hammer 12 may be a hammer drill having an operation mode of "impact only". EXAMPLES
[0046] The rail bond removal device 1 of this embodiment was used to remove the terminal 81 of the rail bond. The target rail bond was a commonly used type ("CL-70"). The cross-sectional area of the bond wire of the rail bond ("CL-70") was 70 mm. 2 The work required one person. The time required to remove rail bond terminal 81 was 2 to 4 seconds per rail bond terminal. After removing multiple rail bonds, the worker's sense of fatigue was rated as "1", the lowest on a three-point scale.
[0047] Comparative Example 1 For the same type of rail bond as in Example 1, the rail bond removal work was carried out using a conventional method without using the rail bond removal device 1. The work required two workers. The time required to remove the rail bond terminals 81 was 5 to 10 seconds per terminal. The worker's sense of fatigue was rated as "3", the highest level on a three-point scale.
[0048] By using the rail bond removal device 1, construction time was shortened, the number of workers was reduced from two to one, and worker fatigue was significantly reduced. EXAMPLES
[0049] A different type of rail bond ("HP type bond") from that in Example 1 was used. The rail bond was a low-temperature soldering type, and could be reused after removal. Other conditions were the same as in Example 1. The work required one person. The time required to remove the rail bond terminals 81 was 2 seconds per terminal. The worker's sense of fatigue was rated as "1", the lowest on a three-point scale. Comparative Example 2 The same type of rail bond as in Example 2 was used. Other conditions were the same as in Comparative Example 1. Two workers were required for the work. The time required to remove the rail bond terminals 81 was 2 seconds per terminal. The worker's sense of fatigue was rated as "2", the middle level, on a three-point scale.
[0050] By using the rail bond removal device 1, the number of workers was reduced from two to one, and the fatigue of the workers was reduced. [Explanation of symbols]
[0051] 1 Rail bond removal device 11 Chisel 12 Electric hammer 2 Rail bond removal jig 3 Mounting part 31 Web 32 Inner flange 33 Hook section 34 Outer flange 4 Guide section 41 Cylinder part 5 Pedals 6 Arm section
Claims
1. A rail bond removal tool for removing a rail bond from a rail, comprising: A mounting portion that is detachably attached to the head portion of the rail; a guide portion for positioning a chisel that is supported by the mounting portion and strikes a terminal of a rail bond; a pedal located lower than the head of the rail, higher than the bottom surface of the rail, and outside the track from the mounting portion; an arm portion that supports the pedal on the mounting portion, The mounting portion has a web, an inner flange, a hook portion, and an outer flange, The web is a portion that is placed on the top of the rail, The inner flange is a portion extending downward from an end of the web on the inner side of the track, the hook portion protrudes from a lower end of the inner flange toward the rail body and is hooked onto a jaw portion of the rail, A rail bond removal jig characterized in that the outer flange is a portion extending downward from an end portion of the web on the outer side of the track.
2. The guide portion has a cylindrical portion through which a shaft portion of the chisel is inserted, The chisel shaft portion has a degree of freedom in a striking direction relative to the cylindrical portion, 2. The rail bond removal jig according to claim 1, wherein the inner side of the cylindrical portion has a vertical width greater than a horizontal width in the longitudinal direction of the rail.
3. 2. The rail bond removal jig according to claim 1, wherein the arm portion has a shape that avoids interference with a rail fastening device when the mounting portion is attached to the head of a rail.
4. A rail bond removal device for removing a rail bond from a rail, comprising: The rail bond removal jig according to any one of claims 1 to 3, A chisel for striking the rail bond terminals, and an electric hammer for strikingly driving the chisel.
Citation Information
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