JPS637431B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention is intended to prevent railway rail points in snowy regions of northern countries from interfering with traffic due to snow accumulation or freezing during the winter season.

When installing equipment to prevent such snow damage and freezing, the heat source may be a hot water type, hot air type, hot oil circulation type, antifreeze circulation type, etc. However, with hot water type, if the pump heater etc. breaks down, This is not a good method in terms of thermoeconomics because hot water piping may be damaged due to freezing and expansion of the water, and hot water must be passed day and night in winter, regardless of temperature.

Secondly, hot air type does not have the disadvantages of hot water type, but because the heat content per unit volume is significantly smaller than that of hot water, not only does it require a large amount of air volume for the same amount of heating, but it can also be heated over long distances. It is impossible to reach the wind, and the effective distance for uniform heating is no more than 10 m. Moreover, not only is the device large and expensive, but the heating efficiency is also extremely low.

Next, the warm oil or antifreeze circulation system has the disadvantage that if the system is damaged, the oil or antifreeze may leak out near the rails, causing pollution.

Electric heating does not have any of the drawbacks of the hot water type, hot air type, and hot oil circulation type described above. However, the conventional method of attaching the heating cable to the side of the tongue rail receiving plate at the rail point has the disadvantage that the heating cable alone has a short lifespan due to locally high temperatures, and is susceptible to rail vibration when trains pass. This can lead to disconnection accidents, making it impractical.

In order to eliminate the above-mentioned drawbacks, this device uses a skin current heating tube as a heating element.Skin current heating tubes are classified into series skin current heating tubes and induced skin current heating tubes. Published by Electrical Engineering Handbook, 1978 edition, page 1578, but here I will briefly explain the drawings.
Fig. 1 shows a series skin current heating tube, and Fig. 2 shows an induced skin current heating tube. An insulated wire or cable, 3, which is passed relatively freely through the AC power supply, usually at commercial frequency.

In the case of Figure 1, one terminal of the AC power supply 3 is connected to the steel pipe 1.
Connect the other terminal of the AC power supply 3 to one end of the insulated wire 2 with the connecting wire 4, and connect the other terminal 5 of the steel pipe 1 to the other end of the wire 2 with the connecting wire 4''. The insulated wire 2 and the steel pipe 1 are connected in series to the AC power source 3, and in the case of FIG. and also two steel pipes 1,
1' is electrically connected at both ends with shorting pieces 7 and 8, and connected to a power source 3, connecting wires 4 and 4', and wire 2.
The steel pipe 1 or 1' in Figs. 1 and 2 has a wall thickness of t (cm) and a length of l ( cm),
If the inner diameter of the steel pipe is D (cm) and the thickness of the skin, which indicates the range in which alternating current flows through the inner skin of the steel pipe, is S (cm), then under the conditions t>2S, l>>D, D>>S. Since the alternating current i hardly flows out of the steel pipe 1, even if it comes into metallic contact with the outer surface of the steel pipe, no arc will be generated or there will be no risk of electric shock to humans or animals. Therefore, the series skin current heating tube shown in FIG. 1 and the induced skin current heating tube shown in FIG. 2 have been generally used for pipeline heating and insulation and roadbed surface heating. Although the single-phase circuit is explained in Figures 1 and 2, it is also possible to configure a multi-phase circuit by combining these heating tubes, and the heating tubes are not limited to circular cross sections, but can also have cross sections of various shapes. You can also use.

As is clear from the above explanation, the skin current heating tube is not only protected mechanically by the insulation of the electrical wire 2, which is the weak point of electrical equipment, but also by the steel pipes 1, 1'. 1' heat generation is steel pipe 1,
1' is directly welded to a single steel plate with a small area, and the heat generated by it is effectively transferred to the side surface of the receiving plate of the tongue rail at the rail point and the bottom surface of the rail through the steel plate. The temperature difference between the electric wire and the structure it is in contact with is extremely small, 1 to 5 degrees Celsius, and unlike other heating elements, there is no danger of the wire insulation being exposed to high temperatures. In addition, since there is a gap between the steel pipe and the electric wire, the vibrations caused by the rail when a train passes are buffered, and there is no risk of the electric wire breaking.

Conventionally, skin current heating tubes have been thought of as a type of heating element, but this invention has another effect: skin current heating tubes are a type of electromagnetic equipment, just like transformers. Therefore, it utilizes electromagnetic vibrations generated in the same way as transformer cores.

In other words, since the insulated wire 2 passed through the steel pipe 1 is not fixed inside the steel pipe and can move relatively freely, and is not located at the magnetic center of the steel pipe 1 (in this case, the center of the steel pipe), it is affected by electromagnetic force. , the electric wire 2 vibrates slightly at a frequency twice the frequency of the current i.

This vibration is transmitted to the steel pipe 1 through which the electric wire 2 passes, and the skin current heating tube vibrates slightly when energized, preventing the formation of ice on the surface at the early stage of freezing through the steel plate.
Alternatively, it has the effect of facilitating the peeling off of generated ice.

FIGS. 3 to 7 are explanatory diagrams of one embodiment of the present invention. The present invention will be explained below with reference to these figures.

Figure 3 is a plan view showing the general outline of the railway rail point section, Figure 4 is its longitudinal cross-sectional view, and Figure 5 is 2
A set of heat-generating steel plates 9, 9'...9'' is shown, which plays the main role of a point antifreeze device. 10 is a track rail, 10' is a tongue rail, 11 is a tongue rail receiving plate, 12 is a sleeper, 13 is a heat generating steel plate 9,
9',...9'' electrical connection connector between each other, 14
is a metal fitting for adjusting the distance between the heat-generating steel plates 9, 9'...9'', which is made up of bolts, nuts, and lock nuts. By adjusting this metal fitting, the heat-generating steel plates 9, 9'...9'' can be brought into close contact with the receiving plate 11, and allow and facilitate heat transfer between At the same time, the heat-generating steel plates 9, 9'...9'' are in close contact with the lower surfaces of the track rail 10 and the tongue rail 10' to enable heat transfer.The track rail and the tongue rail 10' are required to insulate the signal current. Since they must be electrically insulated from above, care must be taken when using series skin current heating tubes, and in Figure 3 the electric wires are separated like 3 and 3'. , various other means are possible.

FIG. 5 is a schematic plan view mainly showing electrical connections in the case of two sets of heat generating steel plates 9 and 9', and FIG. 6 is a side view thereof. Codes 1 to 14 in Figures 5 and 6
are the same as those in Figures 1 to 4, and 15,1
5', 15'' are heat generating steel pipes 1, 1' and flat steel plates 16, 1
6' welding. 17 is a heat insulation layer, which is a heat generating steel pipe 1,
1' heat generation as effectively as possible.
6 and 16', preventing heat radiation to the lower part. 18 is a cover for the heat retaining layer 17. End box 1 with lids 20, 20' at both ends of heat-generating steel pipes 1, 1'
9, 19' are provided, and the end boxes 19, 19' are welded to the exothermic steel pipes 1, 1' by welding 15, 15', 15'', so the end boxes are simultaneously connected to the shorting pieces 7, 8 in FIG. fulfill the role of

Although FIG. 5 shows the connection of the induced skin current heating tube of FIG. 2, it is of course possible to utilize the series skin current heating tube of FIG. 1.

FIG. 7 shows an example of the interval adjustment fittings 14 between the heat generating steel plates 9 in a set of two, the protective adjustment tube 21 of the insulated wire 2,
22 is a vertical cross-sectional side view schematically showing a portion 22. FIG. The spacing adjustment fitting 14 is shown as having one bolt and four nuts, and after adjusting the spacing by turning the nut, it is fixed with a lock nut.

The protective adjustment pipes 21 and 22 are connected to respective heat generating steel plates 9.
The inner tube 22 is inserted into the outer tube 21 and can be moved in and out of each other in the axial direction, so the insertion depth changes depending on the adjustment interval of the metal fittings 14.
Acts as a protective tube.

Since the heat-generating steel plate of the device of this invention is constructed as described above, it is efficiently prevented from freezing, and it is extremely easy to replace the steel plate in the event of a failure or to attach and detach it during the demand season in winter and the non-demand season in summer. Moreover, the interval can be easily adjusted.

Next, the rail is for a train, and there is a direct current on the rail, and this direct current is diverted onto the heat-generating steel plate of this invention.
Furthermore, there is a possibility that the current may be diverted to the heat-generating steel pipes 1, 1', but to prevent this, the direction of the direct current flowing through the rail and the length direction of the heat-generating steel pipes 1, 1' should be perpendicular to each other. The reason for this is that, in FIG. 7, even if there is a direct current in the horizontal left and right direction, that is, in the rail direction, in the flat steel plates 16, 16', the direct current will go through the trouble of making line contact with the flat steel plates 1, 16' at right angles to the heating steel pipes 1, 16'. Since the amount flowing in a detour in the circumferential direction of ' is zero or extremely small, it does not have a direct current effect on the electromagnetic characteristics of the heat-generating steel pipes 1, 1'.

In this invention, since the skin current heating tube is skillfully used, heat can be transferred effectively, and since the surface area of the heating plate is less than several hundred watts per square meter, freezing can be economically prevented and transportation It does not cause any hindrance.

[Brief explanation of the drawing]

Figure 1 is a diagram explaining the principle of a series skin current heating tube, Figure 2 is a diagram explaining the principle of an induced skin current heating tube, Figure 3 is a plan view of a rail point section of a railway equipped with this invention device, and Figure 4 is a side view thereof, FIG. 5 is a partially cutaway plan view mainly showing electrical connections when there are two sets (four sheets) of heat-generating steel plates in the apparatus of the present invention, FIG. 6 is a side view of the same, and FIG. The figure is a longitudinal cross-sectional view of a space adjustment fitting between a pair of heat generating steel plates and a protective adjustment tube for an insulated wire. 1, 1': Heat-generating steel pipe, 2: Insulated wire, 3, 3':
AC power supply, 4, 4', 4'': connecting wire, 5, 6: terminal, 7, 8: shorting piece, 9, 9', 9'': heat generating steel plate,
10: Track rail, 10': Tongue rail, 1
1: Tongue rail receiving plate, 14: Steel plate spacing adjustment fitting, 16: Flat steel plate, 17: Heat insulation layer.

Claims (1)

[Scope of Claims] 1 A set of two heat-generating steel plates with a plurality of skin current heat-generating tubes welded in parallel to the lower surface of the flat steel plate, and the plurality of sets are electrically connected to a rail on which the heat-generating steel plates are parallel. A rail point that is connected to prevent short circuits, interposed between the receiving plate of the tongue rail and the underside of the rail, making each heat-generating steel plate closely contact the adjacent receiving plate, and equipped with a metal fitting for adjusting the distance between the heat-generating steel plates for easy attachment and removal. Antifreeze device. 2. Claim 1, in which a heat-retaining layer is provided on the lower surface of the heat-generating steel plate to prevent heat radiation from downward.
Rail point antifreeze device. 3. The rail point antifreeze device according to claim 1 or 2, wherein the length direction of the heat-generating steel pipe welded parallel to the heat-generating steel plate, that is, the current direction, is orthogonal to the rail.