JPH0351336Y2 - - Google Patents

Description

[Detailed description of the invention] (Field of industrial application) The present invention is designed to prevent electrical corrosion of underground metal objects such as underground pipelines due to leakage current from electric railway tracks. This invention relates to a forced drainage device that forcibly supplies anti-corrosion current between an electric railway rail and an electric railway rail, using the rail as an anode.

(Prior art and its problems) One of the conventional anti-corrosion current supply mechanisms in forced drainage equipment is a system that constantly supplies a constant amount of large anti-corrosion current corresponding to the operation of electric railways. This method has problems, such as promoting electrolytic corrosion of the rails during times when railway service is suspended, when a small anti-corrosion current is sufficient, interfering with other underground facilities, and consuming large amounts of power. In addition, in order to solve the problems of this method, a method has been developed in which the anti-corrosion current is reduced only when a specific condition, that is, a state in which the leakage current from the railway is low continues for a predetermined period of time, is met. However, since this method gives priority to large current supply, it cannot fully solve the above-mentioned problems, and the structure is also relatively complicated. Furthermore, there is a system that compares a voltage proportional to the anti-corrosion current or the pipe-to-ground voltage with a reference voltage and automatically controls and supplies the anti-corrosion current so that the error is always zero. Although it is possible to perform fine-grained and appropriate control, there are problems in that the configuration is complex and expensive.

The present invention aims to solve the above problems.

(Means for Solving the Problems) The configuration of the present invention will be explained based on FIG. 1 corresponding to the embodiment. In a forced drainage device that forcibly supplies an anti-corrosion current, two current setting means 6a, 6b are configured in the control input section 4 of the variable anti-corrosion current supply means 3 via a switching means 5. , the switching means 5 is configured to be operated by a control means 9 having a potential difference detection section 7 between the rail 2 and the metal body 1 and a comparison section 8 for comparing the detected potential difference and the set potential difference, and the current setting means 6a, 6b include , the upper limit current and the lower limit current are set appropriately.

(Function) In the above configuration, the electric train 10 is not running nearby, the leakage current from the rail 2 is small, and the potential difference between the rail 2 and the metal body 1 is the set potential difference.
In a state lower than V ₁ , the switching means 5 is switched to the current setting means 6b side by the control means 9 as shown by the imaginary line in the figure, and therefore the control input section 4 of the variable supply means 3 is switched to the side of the current setting means 6b. Since a control signal corresponding to the lower limit current _A1 is added from the current setting means 6b, the variable supply means 3 controls the lower limit current A1.
We supply _A1 .

In this way, when the leakage current from the rail 2 is small, by performing corrosion protection with a small anti-corrosion current, it is possible to reduce the electrolytic corrosion of the rail 2, reduce power consumption, alleviate the excessive corrosion protection potential at the discharge point, and Interference with other buried facilities can be alleviated.

As the electric train 10 starts running, the leakage current from the rail 2 increases, and the potential difference between the rail 2 and the metal body 1 gradually increases. When this potential difference exceeds the set potential difference V ₁ , the control means 9 The switching means 5 is connected to the current setting means 6a as shown by the solid line in the figure.
Switch to the side. Therefore, a control signal corresponding to the upper limit current A2 from the current setting means 6a is applied to the control input section 4 of the variable supply means ₃ , so that the variable supply means ₃ supplies the upper limit current A2, and thus Sufficient corrosion protection can be achieved in response to an increase in leakage current.

Then, when the train 10 runs away and the leakage current decreases again and the potential difference between the rail 2 and the metal body 1 falls below the set potential difference _V1 , the control means 9 switches the switching means 5
is switched again to the current setting means 6b side, and thus corrosion protection is performed again with a small corrosion protection current.

The upper limit current A ₂ and the lower limit current A ₁ can be appropriately set in the current setting means 6a, 6b depending on the conditions of the place of application.

(Effects of the invention) As described above, the present invention comprises a two-system current setting means via a switching means in the control input section of the variable supply means for corrosion protection current, and this switching means is connected to the rail and the underground metal body. Switch instantly according to the potential difference between
Since the corrosion protection current is switched between the upper limit current and the lower limit current, when the leakage current from the rail is small, corrosion protection is performed with a small corrosion protection current, which reduces electrical corrosion of the rail, reduces power consumption, It is possible to alleviate excessive corrosion protection potential at the discharge point and to alleviate interference with other buried facilities, and when leakage current increases, appropriate corrosion protection can be carried out by supplying a large corrosion protection current. It has the effect of being able to In this way, the present invention has a simple configuration,
The effect is that appropriate corrosion protection can be performed at all times depending on the amount of leakage current.

[Brief explanation of the drawing]

FIG. 1 is a schematic system explanatory diagram showing the configuration of the present invention, and FIG. 2 is an explanatory diagram schematically showing the operation of the present invention. Code 1... underground metal body, 2... electric railway rail,
3... variable supply means, 4... control input section, 5...
Switching means, 6a, 6b...Current setting means, 7...
Potential difference detection section, 8... Comparison section, 9... Control means,
10...train.

Claims (1)

[Scope of utility model registration request] In a forced drainage device that forcibly supplies an anti-corrosion current between an underground metal body and an electric railway rail, using the rail as an anode, a control input section of a variable anti-corrosion current supply means is connected to two The switching means constitutes a current setting means of the system, and is operated by a control means having a potential difference detection section between the rail and the metal body and a comparison section for comparing the detected potential difference and the set potential difference, and the current setting means includes: , an anticorrosion current supply mechanism in a forced drainage device configured to appropriately set an upper limit current and a lower limit current, respectively.