JP2646211B2 - Submerged pump with liquid level measuring means - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a submerged pump with liquid measuring means for an underground tank installed in a gas station for supplying gasoline to automobiles and the like.

[Conventional technology]

In such a gas station, as is conventionally known, a tank is buried under the gas station premises, gasoline is stored here, and a fixed or suspended fueling device is installed on the ground, and the oil tank in the underground is installed. And the oil supply device are connected by an oil supply pipe, and gasoline in the oil storage tank is sent to the oil supply device by a pump.

By the way, as a place for installing the pump for pumping gasoline, if the capacity of the underground tank is relatively small, for example, 10 kl or less, install the pump in the refueling machine case above the ground or in the pump room, and use this pump to install the underground tank. Pumps gasoline from above to a refueling unit on the ground. However, if the capacity of the underground tank is large, for example, 30 kl or more, and the head is large, or if the capacity of a small tank is buried deep underground and the head is large, it is not enough to install a pump on the ground. As a result, a submerged pump (submerged pump) is installed in the underground tank to pump gasoline from underground to the ground.

On the other hand, to manage the amount of gasoline remaining in the oil storage tank,
Although a liquid level measuring means is provided in the tank, a capacitance type one utilizing the difference in the dielectric constant between oil and air may be used as the liquid level measuring means.

Conventionally, the submerged pump and the capacitance type electrode rod have been separately and independently installed in the underground tank.

[Problems to be solved by the invention]

For this reason, two members are separately installed in an underground tank, and installation work is troublesome.

Further, for example, JP-A-54-125501 and JP-A-58-125501
As can be seen in JP-A-123431, both the submerged pump and the capacitance type electrode rod are long and thin cylinders, and they are separate even though there are parts that can be shared as members. Was also high.

An object of the present invention is to solve the above-mentioned disadvantages of the conventional example, and when installing a submerged pump and a capacitance type liquid level measuring means in an underground tank, they are integrated to reduce the number of parts and cost. And installation is easy,
It is another object of the present invention to provide a submerged pump with a liquid level measuring means that can ensure the safety of the pump.

[Means for solving the problem]

In order to achieve the above object, the present invention provides a submerged pump having a cylindrical pumping tube at the top, wherein an outer tube having a diameter slightly larger than the pumping tube is formed concentrically around the pumping tube via an insulator holder. Fixed to the top of the submerged pump,
A gas outflow port communicating with a space formed between the pumping tube and the outer tube is provided at an upper portion of the outer tube, and a liquid outflow port communicating with the space is provided at a lower portion of the outer tube, and attached above the pumping tube. The positive side of the LC transmitter body is connected to the outer tube, and the negative side is connected to the pumping tube.
The gist of the present invention is to output a liquid level signal from the transmitter body to a calculation display for displaying a liquid amount.

[Action]

According to the present invention, an outer pipe for measuring the liquid level is provided concentrically outside the pumping pipe of the submerged pump, and a gas outflow port is provided at the upper part of the outer pipe, and a liquid outflow port is provided at the lower part of the outer pipe. The tubes are used as positive and negative electrode tubes of a capacitance type liquid level measuring means, respectively.

Then, since the outer pipe is provided around the pumping pipe rising from the upper part of the submerged pump, the liquid level measuring means is necessarily provided above the pump, and the pump is driven without any liquid. Can be reliably prevented.

〔Example〕

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings.

FIG. 1 is a vertical sectional front view showing an embodiment of a submerged pump with a liquid level measuring means of the present invention, and FIG. 2 is a cross-sectional plan view of a double pipe portion of the main part of the same. The submerged pump 2 is provided at the bottom of the underground tank 1. The submerged pump 2 is provided with a liquid inlet 3 at a lower portion and a pumping tube 4 is set up from an upper portion. Refueling pipe 7 communicating with a refueling machine (not shown) via a joint 6 in a box 5 usually called a manhole.
Connected to.

On the other hand, around the pumping tube 4 as a liquid level measuring means,
An outer pipe 8 having a diameter slightly larger than this is arranged concentrically, and the lower end of the outer pipe 8 is fixed to the upper part of the submerged pump 2 with an insulator holder 9a. Is fixed to the outer peripheral surface of the pumping tube 4 serving as the inner tube by the insulator holder 9b at the position protruding from the same. 10a,
Reference numeral 10b denotes a gas outflow port and a liquid outflow port provided at the upper portion and the lower portion of the outer tube 8, respectively.

Then, a transmitter body 11 having an LC transmitter is attached to the outside of the pumping tube 4 at a position above the outer tube 8, and an outer tube is attached to the plus side of the transmitter body 11 as a variable capacitor of the LC transmitter. 8 and the pumping tube 4 is connected to the minus side. In this manner, the outer tube 8 and the pumping tube 4 are each configured as a capacitor having a capacitance between them as plus and minus electrode rods, and are formed in the space 15 formed between the pumping tube 4 and the outer tube 8. And a capacitance type liquid level measuring means based on the ratio of the amount of oil flowing into the liquid to the amount of residual air.

Further, a signal line 14 connects the transmitter main body 11 to a calculation display 13 for displaying the amount of oil in the underground tank 1 provided in an office on the ground or the like via a connector 12 provided in the box 5. did. The operation indicator 13 has a function of converting the liquid level measured by the liquid level measuring means into a liquid amount by adding data such as the shape of the underground tank 1.

In the figure, reference numeral 17 denotes a protective tube that connects the underground tank 1 and the box 5 and covers the periphery of the transmitter body 11.

Next, the operation will be described in terms of the function as a pump. When oil is supplied to an automobile by a gasoline refueling machine on the ground, the oil 18 stored in the underground tank 1 is supplied by the submerged pump 2 through the liquid inlet 3. It is pumped into the pumping pipe 4, further supplied to the oil supply hose of the gasoline oil supply machine through the oil supply pipe 7 via the joint 6, and supplied from the oil supply nozzle at the tip of the oil supply hose to the gasoline tank of the automobile.

Next, the function of measuring the liquid level of the oil 18 in the underground tank 1 will be described. The oil 18 is formed in the space 15 formed between the pumping pipe 4 as the inner pipe and the outer pipe 8 via the liquid port 10b. In the space 15, a layer of air 19 is formed above and a layer of oil 18 is formed below.

On the other hand, the pumping tube 4 as the inner tube is a negative electrode rod as a variable condenser, and the outer tube 8 is a positive electrode rod,
The capacitance value between the electrode rods determined by the dielectric constant between the air 19 and the oil 18 in the space 15 is detected by the transmitter body 11.

Although this capacitance value indicates the liquid level, it is indicated by an analog value, so if it is transmitted to the operation display 13 as it is, it will be attenuated and the correct liquid level cannot be grasped. Convert and capture the liquid level at the oscillation frequency,
This is sent to operation display 13 via signal line 14.

Based on the frequency indicating the liquid level position sent, the operation display 13 converts the liquid level by adding tank shape data and the like to this, and displays the volume of the oil 18 in the underground tank 1 on the display unit. .

The manager of the gas station knows the remaining amount of the oil 18 in the underground tank 1 by looking at the liquid level display, and replenishes it appropriately. Since the space 15 for detecting the capacitance value is formed above the submerged pump 2, the height 15 of the submerged pump 2 is approximately 30.
It is impossible to measure the liquid level below cm.
If it is less than cm, the pump function may be impaired, and oil is replenished before that, so there is no problem in measuring the liquid level.

The pumping pipe 4 is provided with an oil supply pipe 7 and the like via a joint 6 including the submerged pump 2. However, since the pumping pipe 4 is a negative electrode, it becomes a ground electrode.
On the other hand, since the outer tube 8 is fixed to the pumping tube 4 and the submerged pump 2 by the insulators 9a and 9b, there is no possibility of causing any electrical inconvenience.

〔The invention's effect〕

As described above, the submerged pump with the liquid level measuring means of the present invention is a liquid pumping pipe in which when the submerged pump and the capacitance type liquid level measuring means are installed in the underground tank, both are integrated. Because the electrode and the electrode rod are shared, the number of parts can be reduced and the cost can be reduced, the installation is simple, and the safety of the pump can be ensured.

[Brief description of the drawings]

FIG. 1 is a vertical sectional front view showing an embodiment of a submerged pump with a liquid level measuring means of the present invention, and FIG. 2 is a cross-sectional plan view of a double pipe portion of the main part of the same. 1 ... underground tank, 2 ... submerged pump 3 ... liquid inlet, 4 ... pumping pipe 5 ... box, 6 ... joint 7 ... oil supply pipe, 8 ... outer pipe 9a, 9b ... insulator Holder, 10a… Gas outflow port 10b …… Liquid outflow port, 11 …… Transmitter body 12 …… Connector, 13 …… Calculation display 14 …… Signal line, 15 …… Space 17 …… Protective tube, 18 …… oil 19 …… air

Claims (1)

(57) [Claims] 1. A submerged pump having a cylindrical pumping tube at the top thereof, wherein an outer tube having a diameter slightly larger than the pumping tube is concentrically formed on the upper part of the submerged pump via an insulator holder. A gas outlet and outlet communicating with a space formed between the pumping tube and the outer tube is fixed at an upper portion of the outer tube, and a liquid outlet and outlet connected to the space is provided at a lower portion of the outer tube. Connect the plus side of the LC transmitter body attached above to the outer tube and the minus side to the pumping tube to form a capacitance-type liquid level measuring means.The liquid level signal from the LC transmitter body is A submerged pump with a liquid level measuring means, wherein the output is output to a calculation display for displaying the amount.