JPS6110404Y2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a gas venting structure for an electrical device that is housed in a pressure-balanced oil container and is used underwater for opening and closing operations.

It is desirable that electrical equipment used underwater, such as a power distribution box on a submersible, for opening and closing operations, be able to withstand water pressure and prevent water from entering, be lightweight, small, and highly reliable.

Conventional electrical devices used underwater to perform opening and closing operations were installed in pressure-tight compartments and operated in air confined within the compartment. The containers for pressure-resistant compartments are expensive, so they should be made as compact as possible to accommodate the crew and passengers.
Since most of the time is occupied by measuring equipment, etc., installing electrical equipment in this area will constrict the space, and opening and closing of the electrical circuit may have a negative effect on the instruments. If stored in a container, it would be very expensive and maintenance would be difficult.

This invention eliminates the above-mentioned drawbacks, and is housed in a pressure-balanced oil-filled container that is easy to maintain, lightweight, and compact.
An object of the present invention is to provide an oil-immersed electric device which prevents water from entering and allows gas to be vented.

Next, embodiments of the present invention will be described below with reference to the drawings. The figure is a side cross-sectional view of an oil-immersed electric device for underwater use according to an embodiment of the present invention. In the figure, reference numeral 1 denotes an oil container that houses an electric device 2 that performs opening and closing operations, and is equipped with an oil filler plug 3 at the top and a drain plug 4 at the bottom. Further, a pressure equalizing device 5 is attached to one of the walls of the container 1, which is in contact with the water outside the container and the oil inside the container, and absorbs the thermal expansion of the oil inside the container. At the top of the container 1, an inverted U-shaped degassing pipe 7 with a differential pressure valve 6 attached to its tip is attached to penetrate the container wall. It is easy to open and close electrical equipment in oil, and the arc is easily broken, but gas is generated by the arc during opening and closing. This gas accumulates at the top of the container,
It gathers in the empty space inside the gas vent pipe 7. The amount of gas increases, and if it is left in the container, it will pressurize the oil surface and push the oil out of the pressure equalization device, putting a strain on the pressure equalization device. A gas vent pipe 7 is provided in order to always balance the pressure with the water pressure. A container 1 housing an electric device 2 is filled with oil while leaving air in a gas vent pipe 7. When the container is submerged in water, the oil pressure inside the container increases as the water pressure outside the container increases, and the air in the gas vent pipe 7 is compressed until it becomes equal to the oil pressure, maintaining a balance with the outside water pressure. The differential pressure valve 6 opens when a pressure difference occurs between the inside and outside, and is closed when the inside and outside pressures are balanced. When the electric device operates with the container submerged in water, the generated arc gas accumulates at the top of the container and enters the gas vent pipe, pressurizing the oil level, so the gas pressure in the pipe 7 becomes higher than the water pressure, and the differential pressure valve 6 closes. When activated, gas is released outside the container. When the gas is released, the internal pressure decreases and the differential pressure valve closes, and the gas in the gas venting pipe becomes balanced with the water pressure again, but some water flows into the gas venting pipe 7 until the differential pressure valve closes. Intrusion is inevitable. However, even if water enters the pipe, there will always be gas left in the inverted U-shaped gas vent pipe 7, so this gas will be pressurized and the pressure will increase, causing the water to reach the oil level. prevent. By forming the gas vent pipe into an inverted U shape, the space for protruding from the container is made small, the area for preventing water intrusion is made as long as possible, and the gas is easily released.

According to this invention, the electrical equipment used underwater for opening and closing operations is housed in a pressure-balanced oil container equipped with a completely waterproof gas venting device, which has the great effect of improving reliability and maintainability and reducing costs.

[Brief explanation of the drawing]

The figure is a sectional side view of an oil-immersed electric device for underwater use according to an embodiment of the present invention. 1...Oil container, 2...Electrical device, 3...Lubrication tap, 4...Drain tap, 5...Pressure equalization device, 6...Differential pressure valve, 7...Gas vent pipe.

Claims (1)

[Scope of utility model registration request] An electric device that opens and closes when used underwater and is housed in an oil container equipped with a pressure equalization device to maintain a balance between internal and external pressures.A differential pressure valve is installed at the top of the oil container at the tip. An oil-immersed electric device for underwater use, characterized by having an inverted U-shaped gas vent pipe installed through the container wall.