US20130168461A1

US20130168461A1 - Expanding insert for a rail spike

Info

Publication number: US20130168461A1
Application number: US13/820,924
Authority: US
Inventors: Christian Schnyder
Original assignee: SERSA GROUP AG (SCHWEIZ)
Current assignee: SERSA GROUP AG; SERSA GROUP AG (SCHWEIZ)
Priority date: 2010-09-06
Filing date: 2011-09-05
Publication date: 2013-07-04
Also published as: EA022378B1; CA2809226A1; EP2426257A1; EA201001468A1; WO2012032011A1

Abstract

An expanding insert (4) for rail spikes is bent from a bar material and has two first and second limbs (40, 41) which are connected to one another via a first bend (43) and extend at least approximately parallel to one another, and a third limb (42) connected via a second bend (44) to the second limb (41). The first limb (40) and the second limb (41) are located in a common first plane (E1) and the third limb is located in a second plane (E2) which is substantially perpendicular to the first plane.

Description

TECHNICAL FIELD

The invention relates to an expansion or expansion insert for rail spikes according to the preamble of patent claim 1.

PRIOR ART

As a. result of stressing of railroad tracks, the crosstie screws and rail spikes loosen. The track gauge and guiding distance and also the rail height are changed. During rehabilitation of the tracks, the firm screw fit is re-established in that the old crosstie screws are removed and the hole is drilled out and cleaned. Subsequently, an expansion inert is introduced into this hole. The hole is filled with grouting compound and subsequently a new crosstie screw is screwed in, wherein the expansion insert provides the new crosstie screw with a firm hold. In order to correct the track height, a base plate, preferably a Lupolen base, is laid on the crosstie, usually before the hole is grouted.
This method and the use of the expansion insert have now proven successful for many years. The method is known under the name Traversan crosstie rehabilitation. The method and the associated expansion insert are likewise described in CH 514 734.
For crosstie screws having blunt screws, CH 514 734 proposes using an expansion insert, as per FIG. 5, said expansion insert having the form of a helical spring. For pointed screws, an expansion insert as per FIG. 3 is used. This expansion insert has three axially parallel legs, which are bent from a one-piece bar material. A free end which is at the top in the installed state of the expansion insert is bent substantially horizontally. This bend or catch is intended to be caught by the screw and to serve as an additional screw guide.
In some countries, rail spikes are usually used instead of crosstie screws. However, both of the expansion inserts described in CH 514 734 have the drawback that when used in combination with a rail spike, the pull-out resistance is too low. The pull-out resistance is understood to mean the resistance to a force with which the rail spike is intended to be pulled out of the crosstie. In addition, it was found that the introduction of a rail spike into a hole provided with such an expansion insert is problematic, because the expansion insert has often pushed the spike out of the center axis of the hole.
EP 1 449 961 also discloses an expansion insert, which is advantageous in connection with screws having blunt screw ends. However, similar drawbacks arise from the technical teaching of EP 1 449 361 and the use for rail spikes has proven difficult.

DESCRIPTION OF THE INVENTION

It is an object of the invention to increase the tensile strength of the arrangement and to allow use of rail spikes, in particular having a pointed end.
Such an object is achieved by an expansion insert or expanding insert according to claim 1. Accordingly, an expansion insert for rail spikes has two, first and second legs that are connected together via a first bend and extend at least approximately parallel to one another, and also has a third leg connected to the second leg via a second bend. The first leg and the second leg are located in a common first plane and the third leg is located in a second plane which is substantially perpendicular to the first plane.
As a result, it is possible to create an expansion insert in the case of which all three legs come to lie in the region of the surface of the hole in the crosstie, wherein consequently the cross section of the hole is only minimally reduced with the expansion insert inserted, thereby making it easy to drive in the rail spike.
Preferably, the second plane extends through the second leg, as a result of which the expanding insert can be designed to be even more compact.
Preferably, the first leg has a free end which forms an at least approximately rectilinear extension of the first leg. Particularly preferably, the free end forms exactly a rectilinear extension.
Preferably, the third leg has a free end which forms at least approximately, preferably exactly, a rectilinear extension of the third leg.
Preferably, the first, leg and/or the third leg have at their free end(s) a hooking section which extends at an angle, preferably perpendicularly, to the respective leg.
Preferably, the expansion insert is produced in one piece from a bar material and is manufactured from a special steel.
Preferably, the first bend is located in the first plane and the second bend in the second plane.
Preferably, the first and second legs extend, at least approximately parallel to one another and/or wherein the first leg and the second leg are at least approximately the same length.
Preferably, the third leg extends at an acute angle or at least approximately parallel to the second leg.
Preferably, the first bend and the second bend have the same bending radius. The first and the second bend can in this case be formed in a semicircular or quadrant-shaped manner, wherein two quadrant-shaped bends are then connected via a straight leg. In the latter embodiment, it is also possible to refer to a web.
Further embodiments are specified in the dependent claims.

BRIEF DESCRIPTION OF THE DRAWINGS

Preferred, embodiments of the invention are described in the following text with reference to the drawings, which serve merely for explanatory purposes and should not be interpreted as being restrictive. In the drawings:

FIG. 1 shows a cross section through a railroad crosstie having expansion inserts according to the invention;

FIG. 2 shows a side view of a rail spike for use in combination with the expansion inserts according to FIG. 1;

FIG. 3 shows a view from the front of the rail spike from FIG. 2;

FIG. 4 shows a view from below of the rail spike from FIG. 2;

FIG. 5 shows a side view of an expansion insert from the right;

FIG. 6 shows a front view of the expansion insert according to FIG. 5;

FIG. 7 shows a side view of the expansion insert according to FIG. 5 from the left;

FIG. 8 shows a top view of the expansion insert. according to FIG. 5; and

FIG. 9 shows a perspective view of the expansion insert.

DESCRIPTION OF PREFERRED EMBODIMENTS

FIG. 1 illustrates a cross section through a track section of a railroad crosstie. On a crosstie 1, a rail 2. is fastened to a rib place 5 by means of rail spikes 7. The rail spikes 7 project through openings 50 in the rib plate and extend into holes 3 which are produced in the crosstie 1, wherein the rail spikes 7 are fixed in the holes 3. When the firm spike fit is renewed, in order to fix the rail spikes 7, in each case an expansion insert 4 is lowered into the holes 3 and optionally grouted in a watertight manner therein by means of a grouting compound 6. The rail spikes 7 in the process clamp the rail 2 to the crosstie 1 or rib plate 5.
FIGS. 2 to 4 show an embodiment of a rail spike 7 for use in the track structure according to FIG. 1. The rail spike 7 comprises a head section 70, a shank section 71 adjoining the latter, and a spike tip section 72 which adjoins the shank section 71. The spike tip section 72 ends with a spike tip 73. As seen, from the head section 70, the shank section 71 and the spike tip 72 extend along a center axis M. The head section 70 comes into contact with the rail 2 and clamps the latter against the rib plate 5. The shank section 71 projects through the receiving opening 50 in the rib plate 5 and extends into the hole 3 in the crosstie.
Preferably, the shank section 71 has a square or rectangular cross section. Alternatively, the shank section 71 can also have a circular cross section.
The spike tip section 72 is in this case designed such that the cross section of the spike tip section 72, as seen from the shank section 71, is reduced continuously. Preferably, the degree of reduction is constant over the spike tip section 72 from the shank section 71 to the spike tip 73.
The spike tip 73 can have a multiplicity of different shapes. In the present embodiment, it is provided with a convex edge.
Such a rail spike 7 typically has a diameter in the range of 14 to 19 mm, in particular 16 mm, and a length in the range of 130 to 180 mm, in particular 165 mm.
FIGS. 5 to 9 illustrate the expansion insert 4 according to the invention. It is bent from, a one-piece bar material, preferably composed of special steel, as can also be used for reinforcing iron.
The expansion insert 4 has three legs 40, 41, 42, which are formed in a slightly resilient manner with respect to one another. A first and a second leg 40, 41 extend at least approximately, here exactly, parallel to one another. The first and second legs 40, 41 are connected together via a first bend 43. The first leg 40 and the second leg 41 are located in a common first plane E1. That is to say that for example the center axes along which the legs 40, 41 are part of this first plane E1 and define this first plane 21. This first plane E1 extends in the plane of the drawing sheer in FIG. 6 and is indicated by a line E1 in FIG. 5. The first bend 43 is formed in a manner bent in the first plane E1 of the two legs 40, 41, as can be seen best from FIG. 9.
Opposite the first bend 43, the second leg 41 is adjoined by a second bend 44 which is then followed by the third leg 42. The third leg 42 is located in a second plane E2 which is perpendicular to the first plane E1. Preferably, the second plane E2 is located such that it extends through the second leg 41 such that the third leg 42 comes to lie over the second leg 41. The second plane E2 is illustrated correspondingly in FIG. 5. On account of this arrangement, the expansion insert 4 according to the invention can be used for rail spikes, since the expansion insert is inserted into the hole 3 such that all three legs 40, 41, 42 are in contact with the wall of the hole 3 and none of them reduces the cross section of the hole more than necessary. Consequently, the rail spike can be driven in well without excessive deformation of the expansion insert being necessary, as occurs for example in embodiments of the prior art. In addition, the rail spike is not deflected from its axis during the driving in operation. While the rail spike is being driven in, the legs are pressed into the side wall of the hole. Consequently, the rail spike 7 and the expansion insert 4 are clamped together in the hole.
The first leg 40 has a first free end 46 which forms at least approximately, preferably exactly, a rectilinear extension of this leg 40.
The third leg 42 has a second free end 45, which forms at least approximately, preferably exactly, a rectilinear extension of this leg 42. Preferably, the third leg 42 is adjoined, by a hooking section 47, which extends away from the third leg 42 at an angle, preferably perpendicularly, and extends preferably in the second, plane E2. The hooking section 47 is pushed into the wood of the crosstie by the hammering down of the rail spike, it being possible in this way to further increase the resistance to pulling out,
Optionally, the first leg 40 can comprise a hooking section (not illustrated here), which is designed in an analogous manner to the hooking section 47.
The second leg 41 is preferably designed to be longer than the first leg 40, as can be seen in FIG. 2. The third log is preferably designed to be shorter than the two other legs 40, 41. However, it extends preferably along at least two thirds of the length of the expansion insert 4.
Preferably, all three legs 40, 41, 42 extend parallel to one another. Alternatively, the third leg 42 can extend at an acute angle to the second leg 41, as can be seen best in FIG. 3. Both embodiments are advantageous, since both provide a very compact structure.
Preferably, the first bend 43 and the second bend 44 have the same bending radius, this being advantageous with regard to the compact structure. On account of the arrangement of the first bend 43 and the second bend 44, the expansion insert can be designed to be very compact, this allowing insertion into holes 3 which have a comparatively small diameter, as is usual for holes for rail spikes.
The first leg 40 typically has a length from the free end 46 to the first bend 43 of 75 to 105 mm. Particularly preferred is a length range between 78 and 98 mm, in particular 93 mm.
The second leg 41 typically has a length from the first bend 43 to the second bend 44 of 90 to 120 mm.
Particularly preferred is a length range between 95 and 110 mm, in particular 100 mm.
The third leg 42 typically has a length from the free end 45 to the second bend 44 of 65 to 100 mm. Particularly preferred is a length range between 83 and 93 mm, in particular 88 mm.
Both bends 43, 44 have preferably a radius of 6 to 12 mm, particularly preferably of 8 to 10 mm, in particular 9 mm.

LIST OF REFERENCE SIGNS

1 Crosstie
2 Rail
3 Hole
4 Expansion insert
40 First leg
41 Second leg
42 Third leg
43 First bend
44 Second bend
45 Free end
46 Free end
47 Hooking section
5 Rib plate
50 Receiving opening
6 Grouting compound
7 Rail spike
70 Head section
71 Shank section
72 Spike tip section
73 Spike Lip
M Center axis

Claims

1. An expansion insert (4) for rail spikes, wherein the expansion insert is bent from a bar material, has two, first and second legs (40, 41) that are connected together via a first bend (43) and extend at least approximately parallel to one another, and also has a third leg (42) connected to the second leg (41) via a second bend (44), characterized in that the first leg (40) and the second leg (41) are located in a common first plane (E1), and in that the third leg is located in a second. plane (22) which is substantially perpendicular to the first plane.

2. The expansion insert as claimed in claim 1, characterized in that the second plane (E2) extends through the second leg (41).

3. The expansion insert as claimed in either of the preceding claims, characterized in that the first leg (40) has a free end (46) which forms an at least approximately rectilinear extension of the first leg (40).

4. The expansion insert as claimed in claim 3, wherein the free end (46) of the first leg (40) forms exactly a rectilinear extension of the first leg (40).

5. The expansion insert as claimed in one of the preceding claims, wherein the third leg (42) has a free end (45) which forms at least approximately, preferably exactly, a rectilinear extension of the third leg (42).

6. The expansion insert, as claimed in one of the preceding claims, wherein the first leg (40) and/or the third leg (42) have at their free ends (46, 45) a hooking section (47) which extends at an angle, preferably perpendicularly, to the respective leg (40, 42).

7. The expansion insert as claimed in claim 6, characterized in that the hooking section arranged on the first leg (40) is located in the first plane (E1), and/or in that the hooking section (47) arranged on the third leg (42) is located in the second plane (E2).

8. The expansion insert as claimed in one of the preceding claims, wherein it is produced in one piece from a bar material.

9. The expansion insert as claimed in one of the preceding claims, wherein the first bend (43) is located in the first plane, and/or wherein the second, bend (44) is located in the second plane.

10. The expansion insert as claimed in one of the preceding claims, wherein the first and second legs (40, 41) extend at least approximately parallel to one another and/or wherein the first leg (40) and the second leg (41) are at least approximately the same length.

11. The expansion insert as claimed in one of the preceding claims, wherein the third leg (42) extends at an acute angle or at least approximately parallel to the second leg (41).

12. The expansion insert as claimed in one of the preceding claims, wherein the third leg (42) is designed to be shorter than the first and/or second leg (40, 41).

13. The expansion insert as claimed in one of the preceding claims, wherein the third leg (42) extends along at least two thirds of the length of the expansion insert.

14. The expansion insert as claimed in one of claims 1 to 9, wherein the second leg (41) is designed to be longer than the first leg (40).

15. The expansion insert as claimed in one of the preceding claims, wherein the first bend (43) and the second bend (44) have the same bending radius.