JPH0629753B2 - Wireless liquid level measuring device - Google Patents

Description

Description: TECHNICAL FIELD The present invention relates to a device for detecting the liquid level of an underground tank buried in a gas station or the like and wirelessly transmitting the liquid level to a remote place, and more specifically, this device. The present invention relates to a device having a feature in a mounting portion of a transmitting antenna used in

(Prior Art) Generally, at a gas station, the liquid level of fuel oil or the like stored in an underground tank is detected by a float type level gauge,
This is converted into an electric signal and transmitted to a monitor device or the like in an office located away from the tank.

Although a transmission line is usually used for this transmission, the wiring work of the transmission line has a problem that the cost is increased in terms of peeling pavement, burying a conduit, re-paving, and the like.

On the other hand, a device that converts the liquid level into a frequency and wirelessly transmits it is excellent in that it does not require special wiring work, but on the other hand, it does not work in the iron manhole in the underground tank. Since the device must be installed, there is a problem in that transmission to a remote place is hindered.

(Problems to be Solved by the Invention) The present invention has been made in view of the above-described problems that such a wireless liquid level measuring device has, and an object thereof is to dispose the liquid level measuring device in an iron manhole. Another object of the present invention is to provide a new device capable of transmitting liquid level information to a remote place without any problem even under the condition.

(Means for Solving the Problem) That is, the present invention is, as an apparatus for achieving such a problem, an iron manhole is provided above the underground tank, and a rising pipe connected to the underground tank is opened in the manhole. A case is provided on the pipe, and a transmission means for converting the measurement data of the liquid level in the underground tank into a radio signal is further provided in this case, while it is inserted into the back of the iron lid that covers the opening of the manhole. A concave portion having a mouth is provided, the upper surface of the concave portion is closed with a non-conductive material, and the transmitting antenna connected to the transmitting means through a flexible signal line is inserted and removed from the insertion opening into the concave portion. Thus, the liquid level information can be transmitted to a remote place without any trouble.

(Example) Then, the Example illustrated below is described.

FIG. 5 shows an example of refueling equipment to which the present invention is applied. In the figure, reference numeral 1 is a wireless liquid level measuring device provided in an underground tank 2, and the liquid level measuring device 1 is The liquid level detected by the receiving device 9 of the office 8 located away from the underground tank 2 is transmitted by a carrier wave of radio frequency.

1 and 2 show the detailed structure of the liquid level measuring device 1, which is housed in an iron manhole 3 buried in an upper part of an underground tank 2.

The liquid level measuring device 1 is roughly classified into a mounting base 11 fixed to an upper end of a rising pipe 10 from an underground tank 2, a main body base 15 mounted on the mounting base 11, a circuit component described later, and a lithium battery 25. An electric box base 20 carrying the electric box base 20, an electric box case 30 carrying the mechanical level measuring device 50 so as to be hermetically sealed and connectable to the float 55 of the underground tank 2, and an electric box base 20 and the electric box case 30 are covered and integrated, and these are attached to the main body base 15
It is constituted by a main body case 40 mounted on the top.

To explain these in more detail, the rising pipe 10
A tape insertion hole 16 provided in one half of the main body base 15 is firmly attached to the attachment base 11 fixed to the upper end of the main body base 15 through an O-ring 12 provided on the upper surface of the attachment base 11.

On the other hand, the electric box base 20 is provided with O-rings 21a and 21b on the outer peripheral edge of the upper surface and the tape insertion opening peripheral edge so as to be hermetically sealed by the electric box case 30, and the O-rings 21a and 21b are provided therebetween. It is airtightly joined to the flange 32 portion of the lower end opening. The electric box base 20 is provided with a tape insertion hole 22 in one half at the same position as the tape insertion hole 16 on the main body base 15, and a tape reel 52 described later on the other half.
Is provided with a circuit board 24 for converting the rotation of the above into an electric signal and then converting this signal into a wireless signal for output, and a storage portion 26 for a lithium battery 25 is formed in the remaining other side portion.

On the other hand, an electric box case 30 which is hermetically covered and fixed with screws 31 on the electric box base 20 is provided with a tape drum unit mounting surface 35 having a tape insertion hole 34 in one half thereof, and in the other half thereof. A cover 36 having a shape covering the circuit board 24 and the lithium battery 25 on the electric box base 20 is integrally formed.

50 is a mechanical liquid level measuring device for measuring the level of the liquid contained in the underground tank 2, and this liquid level measuring device 50 is
Insert the tape 5 wound around the tape drum 52 into the tape insertion hole 3
A support bracket 5 for supporting the suspension of the underground tank 2 through 4, 22, 16 and the rising pipe 10.
1 is located on the mounting surface 35 described above. A tape drum 52, to which a biasing force in the winding direction acts via a constant torque spring 59, is axially supported by the support bracket 51, and one end of the tape drum 52 has a float 5 in the underground tank 2.
Even when the tape 53 with the scale 54 connected to the 5 is wound and the battery 25 runs out and transmission becomes impossible, the liquid level can be visually confirmed through the transparent window 45 provided on the top surface of the main body case 40. It is structured so that you can know it. Also,
The support bracket 51 includes a part of the underground tank 2
A detection rod insertion hole 57 for detecting water in the inside is provided, and a horizontal hole 37 of the cover 36 is provided with an O
A potentiometer 60, which is attached airtightly with a ring 61, is located so that this rotation can be taken out as an electrical signal via a face gear 56 fixed to the shaft end of the tape drum 52.

The main body case 40 that covers the electric box case 30 is
The surface of the electric box case 30 and the electric box base 20 is formed from a hole 42 formed in the flange 41 portion of the transparent synthetic resin material whose surface is painted black.
The screws 43 are inserted into the screws 3 and 23, and then screwed into the screw holes 17 of the main body base 15 to integrally fix them.

Reference numeral 29 in the drawing denotes a flexible coaxial cable that connects the transmission circuit on the circuit board 24 and the transmission antenna 14, and the cable 29 has a cable insertion hole 27 formed at the other end of the electric box base 20. Coaxial cable packing 28
Is airtightly inserted through.

In the figure, reference numeral 44 indicates a lid provided on the top surface of the main body case 40 for covering the water detection rod insertion opening, and reference numeral 65 indicates a bracket which is inserted into the notch 62 of the potentiometer 60 to facilitate its attachment / detachment. .

By the way, reference numeral 7 in the drawing denotes a lid of the manhole 3 which is a characteristic part of the present invention. A part of the lid 7 is made of a non-conductive material such as epoxy resin so that its upper surface is flush with the upper surface of the lid 7. -Shaped recess 72 covered with a cover 71
Is formed, and the recess 72 is formed so as to open on the back side of the lid 7.
The transmitting antenna 14 can be inserted into the inside through an insertion port 73 provided at one end of the.

In the wireless liquid level measuring device 1 configured as described above, first, the electric box base 20 and the electric box case 30 are airtightly coupled with each other by the screw 31, and the main body case 40 is covered from above, so that the main body base 15 is covered. Fixed integrally on top. As a result, a highly flammable gas enters between the electric box case 30 and the main body case 40 through the tape insertion port 34, but this gas merely touches the mechanical liquid level measuring device machine 50, Since the highly flammable gas and the water accumulated in the manhole 3 do not enter the inside of the electric box case 30 covered by the cover 36, the circuit components and the battery 25 housed in the cover 36 are corroded or sparked. It is protected without any fear of damage.

Then, after the liquid level measuring device 1 is installed in the manhole 3 in this way, the transmitting antenna 14 connected to the tip of the coaxial cable 29 is put into the recess 72 from the insertion opening 73 opened on the back side of the lid 7, and finally. The top of manhole 3 is covered with this lid 7.
Cover with.

As a result, even if the liquid level measuring device 1 is shielded by the iron manhole 3, the transmitting antenna 14 located in the recess 72 has a non-conductive member covering the upper portion thereof, and therefore the liquid level information is Receiving device 9 provided at a distant position
Etc. will be transmitted without any trouble.

(Effect) As described above, according to the present invention, the lid that covers the upper opening of the manhole is provided with the concave portion having the insertion opening on the back surface, the upper surface of the concave portion is closed with the non-conductive material, and the transmission antenna is inserted. Since it is designed to be inserted into the recess from the mouth,
By simply inserting the transmitting antenna connected to the transmitting means into the recess of the lid, the liquid position information in the tank can be transmitted to the remote place from the shielded manhole through the non-conductive material covering the recess.

Moreover, since the transmitting antenna is positioned so that it can be inserted into and removed from the concave portion provided in the lid, it is possible to appropriately remove or insert the antenna from the concave portion of the lid when replacing the battery or inspecting the internal equipment. , The lid can be attached and removed without applying excessive force to the antenna, and when repairing or transferring the device, the entire device can be easily removed from the manhole and transferred without disconnecting the signal line etc. You can

[Brief description of drawings]

FIG. 1 is an exploded perspective view of an apparatus showing an embodiment of the present invention, FIG. 2 is a sectional view of the same apparatus, and FIG. 3 is a diagram showing an example of a fuel supply facility equipped with the same apparatus. 1 ... Wireless liquid level measuring device 14 ... Transmission antenna 2 ... Underground tank, 24 ... Circuit board 29 ... Coaxial cable, 3 ... Manhole 30 ... Electric box case 40 ... Main body case 50 ... Mechanical type Liquid level measuring device 7 ... Lid 71 ... Cover made of non-conductive material

Claims (1)

[Claims] 1. An iron manhole is provided above an underground tank, a rising pipe connected to the underground tank is opened in the manhole, and a case is provided on the rising pipe. While providing a transmission means for converting the measurement data of the liquid level in the tank into a wireless signal,
An iron lid covering the upper opening of the manhole was provided with a recess having an insertion opening on the back surface, the top surface of the recess was closed with a non-conductive material, and the recess was connected to the transmitting means via a flexible signal line. A wireless liquid level measuring device, characterized in that a transmitting antenna is inserted and inserted into the concave portion through the insertion opening.