JPH0587200B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an improvement of a joint box provided in a refueling device.

[Prior Art] A refueling device has a structure as shown in FIG. 6, for example. That is, in FIG. 6, the oil supply device 1 houses a pump 3 in its casing 2, and the pump 3 is driven by an electric motor 4.
Oil is pumped up from an underground tank (not shown). The pumped oil is measured by a flow meter 5, and is passed through a discharge pipe 6 to a hose 7 and a nozzle 8 at its tip.
From there, fuel is supplied to an automobile tank (not shown).

The flow rate signal from the flow rate pulse transmitter 12 of the flow meter 5 is transmitted to the control device 10, and the control device 10 having the display device 9 displays the amount of oil to be supplied and controls the various devices described above. A signal line 11 coming out of this control device 10 is connected to a signal line 14 at a joint box 13 for signal lines, and the signal line 14 is connected to a POS located in the office of the gas station, so that fuel is supplied between the two. Data is sent and received. Further, the power line 15 of the electric motor 4 is connected to a power line 17 at a power line joint box 16, and the power line 17 is connected to a 200V commercial power source.

As described above, the conventional oil supply system is provided with a joint box for each line in order to prevent noise. That is, in the oil supply device 1 shown in FIG. 6, the signal line joint box 13
When the power line joint box 16 and the power line joint box 16 are integrated into a single joint box, the power line side conductors (15, 17), which generate a large amount of noise, and the power line side conductors (15, 17) are free from noise and are Signal line side conductors (11, 14) that must not exist
There is no shield between them. Therefore, noise generated on the power line side is transmitted to the signal line side, and as a result, the signal line 14 is no longer able to transmit accurate refueling data. Therefore, in the oil supply system shown in FIG. 6, the joint box 13 for the signal line and the joint box 16 for the power line are provided separately, and by arranging them apart from each other, the noise generated on the power line side can be removed from the signal line. This prevents it from being transmitted to the line side.

However, since two joint boxes must be provided, the number of parts in the conventional oil supply system increases accordingly, and the assembly and wiring operations become complicated. As a result, the conventional refueling device has problems in that the manufacturing cost is high and the labor required for safety work is large.

Other conventional technologies include Utility Application No. 59-202032.
The microfilm photographing the specification and drawings attached to the application No.
The outlet is shown with the inside of the box divided by a magnetic shield plate. Jitsugan No. 58-29278 (Jitsukaisho
The microfilm photographing the specification and drawings attached to the application (No. 59-135015) shows a wiring box whose interior is divided by magnetic shield plates and conductor through holes are formed in the walls of each compartment. However, these outlets or wiring boxes are not intended to be used in locations filled with vaporized fuel (vapor), so there is a problem that they cannot be used in dangerous locations such as inside a refueling system.

The microfilm of Utility Model Application No. 56-195789 (Utility Model Application No. 58-103173) shows a pressure-resistant explosion-proof container. However, since there is no disclosure of a structure in which a conducting wire connected to a lead penetrates the outer shell of a flameproof explosion-proof container, this cannot be an effective solution to the above-mentioned problems. That is, unless it is possible to prevent vapor from entering from a location where a conductive wire connected to a lead penetrates the outer shell of a pressure-resistant explosion-proof container, it cannot be applied to a fuel supply device.

Although there is a description in Japanese Utility Model Publication No. 46-25758 regarding a removable shielding plate, there is no disclosure at all about the manner or arrangement in which the shielding plate is removably attached to the outer shell of the container. It is not possible to apply this technique to flameproof containers.

[Object of the Invention] The present invention has been proposed in view of the above-mentioned drawbacks of the prior art, and can be applied to dangerous locations such as inside a fueling system filled with vapor.
In a single joint box, the conductors on the signal line side are connected to each other and the conductors on the power line side are connected to each other, and the noise generated on the power line side has no effect on the signal line side. The aim is to provide a unique joint box.

[Structure of the Invention] The joint box of the present invention is a joint box with a pressure-resistant and explosion-proof structure used in a hazardous area of a refueling system, and a magnetic shield plate detachably attached allows the inside of the box to be connected to a power line side compartment and a signal signal. It is divided into a wire side compartment, and two conductor through holes are formed on the wall surface of each compartment, and the conductor through holes are composed of a hollow screw adapter that screws into the joint box body and the conductor pipe. The joint box main body and the threaded portion between the conductor pipe and the screw adapter constitute a seal against vaporized fuel, and two protrusions are formed at the center of each of the opposing side walls of the box main body. A recess is formed between the two protrusions in which the magnetic shield plate is removably disposed.

Here, the term "dangerous location" in the refueling system refers to a location where the concentration of vaporized fuel (vapor) is high and there is a high possibility of an accident caused by electric fireworks.

The conductor wires on the signal line side and the conductor wires on the power line side that are connected inside the joint box of the present invention are:
For example, the wires may or may not be wired inside a metal conduit. Here, whether or not to route the conductive wire inside the conduit is selected mainly depending on various standards and safety standards regarding the oil supply device. That is, the joint box of the present invention:
It is preferable to change the usage according to various standards and safety standards that differ from country to country or region.

[Function] According to the present invention having the configuration described above,
The conductor wires on the signal line side and the power line side pass through two conductor penetration holes formed in each compartment (signal line side compartment and power line side compartment) and enter the respective compartments in the joint box. be introduced. Since the power line side and the signal line side are divided by the magnetic shield plate, noise generated in the power line side section is completely blocked and is not transmitted to the signal line side section. Therefore, no noise is generated in the conductor wire of the signal line side section. Therefore, it is possible to connect the signal line side conducting wire and the power line side conducting wire within a single joint box.
As a result, joint box installation is facilitated and wiring errors are reduced, thereby reducing the effort required to assemble, wire and maintain the oil supply system.

Here, since the joint box of the present invention has a pressure-resistant and explosion-proof structure, it can be used without any problems even in dangerous locations such as inside a fuel supply system filled with vapor. In other words, even if sparks are emitted from the connection points of the power lines and signal lines, the vapor around the box will not ignite, ensuring safety.

Further, as a result of forming two protrusions at the center of each opposing side wall of the box body, and forming a recess between the two protrusions in which the magnetic shield plate is removably disposed, the magnetic The shield plate is attached removably, so when installing the joint box, wiring, and security work, you can remove the shield plate to increase the work space, significantly reducing the labor required for the work. It can be reduced.

In addition, the conductor through-hole consists of a hollow screw-in adapter that is screwed into the joint box main body and the conductor pipe, and the threaded part between the joint box main body, the conductor pipe, and the screw adapter is Since it forms a seal against vaporized fuel, vapor is completely prevented from entering the inside of the box through the conductor through hole.
Therefore, it is extremely suitable as a joint box used in dangerous areas of oil supply systems.

[Example] Hereinafter, an example of the present invention will be described with reference to FIGS. 1 to 5.

FIG. 3 shows an entire oil supply system equipped with a joint box according to the present invention. The oil supply device, which is generally designated by the reference numeral 20, has approximately the same structure as the oil supply device 1 shown in FIG.
4. An electric motor 26, a flow meter 28, and a control device 30 are built-in.

In this oil supply system 20, a signal line 32 of a control device 30 is connected to a signal line 38 at a joint box 36. In addition, the electric motor 26
Power line 40 is also connected within power line 42 at joint box 36.

Note that the signal line 38 is connected to a POS (not shown) in the office of the gas station, and the power line 42 is not shown.
Connected to 200V commercial power supply.

The joint box 36 described above is shown in detail in FIGS. 1 and 2.

In the embodiment shown in FIGS. 1 and 2, the wires are arranged inside the conduit, and the joint box 36 has an explosion-proof structure, and the main body 44 and the lid 46 are connected to each other. Multiple mounting screws 48, 4
8... are integrally fixed.

The side wall 49 of the main body portion 44 has conducting wire through holes 50, 5.
0... is formed, and this conductor through hole 50
A female thread 52 is cut in the hole. A male screw 56 of a screw-in adapter 54 is screwed into the female screw 52 of the conductor through hole 50 . A male thread 58 is also cut on the opposite side of the screw-in adapter 54, and this male thread 58 is screwed into a female thread 60 cut at the end of the conduit tubes 62, 64.

The power line 40 wired in the conduit 62 and the power line 42 wired in the conduit 64 each enter the joint box 36 through a space 66 in the screw adapter 54, and are connected 68 there. . Note that reference numerals 70 and 72 are ground wires, and these ground wires 70 and 72 are attached to the mounting screw 74.
It is connected to the main body part 44 by.

The connections between the conduit tubes 62, 64 and the joint box main body 44 are sealed by screws formed at both ends of the screw-in adapter 54, so that the connections between the conduit tubes 62, 64 and the joint box main body 44 are sealed by screws formed at both ends of the screw-in adapter 54. ) even if there is vaporized oil, i.e., vapor,
Vapor does not enter the inside of the joint box 36 from the connection between the electrical conduits 62, 64 and the main body 44 of the joint box.

In addition, in FIG. 1, a power line 40 to the electric motor 26 (FIG. 3) wired inside the conduit 62 is shown.
Although only the connection point 68 with the power line 64 wired in the conduit 64, that is, the connection on the power line side, is shown, it is possible to connect the control device 30 (FIG. 3) wired in the conduit 34 to connection between the signal line 32 (Fig. 3) and the signal line 38 wired inside the conduit 35;
That is, the connection on the signal line side is also performed in exactly the same manner as described above.

Two protrusions 7 are provided at the center of the opposing side walls 49, 49 of the main body of the joint box 36, respectively.
6, 76 are formed, and its two protrusions 76, 76
A magnetic shield plate 80 is fitted into the recess 78 between the two. As is clear from FIG. 2, the shield plate 80 blocks substantially the entire height of the interior space of the joint box 36, thereby dividing the interior space into two sections. In FIGS. 1 and 2, the left section of the magnetic shielding plate 80 is the power line side section 82, and the right section is the signal line side section 84.

Power line 4 connected 68 in section 82
Since both wires 0 and 42 are connected to powerful electrical equipment such as electric motors, they generate a large amount of noise. However, since this noise is completely blocked by the magnetic shield plate 80, no noise is generated in the conductor wires on the signal line side connected within the section 84. Therefore, electrical signals such as refueling data are accurately transmitted to the POS.

Incidentally, since the magnetic shield plate 80 is simply fitted into the recess 78 between the protrusions 76, 76, the shield plate 80 can be removed during attachment of the joint box 36, connection (wiring), and security work.

Further, in the figure, reference numeral 86 indicates a screw for attaching a ground wire. This attachment screw 86 is for attaching a ground wire, one end of which is connected to an anchor bolt 87, to the lid portion 46 of the joint box 36. As a result, the main body 4 is tightened by the screw 74.
The ground wires 70 and 72 connected to the lid part 4
6. It is connected to a ground wire and an anchor bolt 87 via a screw 86 to be electrically grounded. It should be noted that near the screw 86, a symbol indicating that this is the location where the ground is to be attached, such as the letter "G", is displayed.

In the embodiments shown in FIGS. 1 to 3, both the signal line and the power line are routed within the conduit, but the conduit may be omitted by using a captire cable. FIGS. 4 and 5 show an embodiment in which a captire cable is used and the conduit is omitted.

In FIG. 4 and FIG. 5, the whole number is 13.
The construction of the joint box 6 is substantially the same as the construction of the joint box 36 of FIGS. 1 and 2.

However, the threaded adapter 54 in the joint box 36 of FIGS. 1 and 2 is replaced with a seal 138 in the joint box 136 of FIGS.
A cover 144 is provided to hold the cover 144 in a recess 142 formed in the main body 140.
It replaces the cover mounting screw 146 for mounting on the cover. Here, cap tire cable 1
48 is a conductor through hole 15 formed in the main body portion 140
However, the seal 138 prevents vapor from entering the joint box 136.

The other details are the same as those shown in FIGS. 1 and 2, so their explanation will be omitted.

[Effects of the Invention] As explained above, according to the present invention, the connection of the signal line and the connection of the power line are made in one joint box, so the installation, wiring, and security of the joint box are extremely simplified. This makes it easier and improves work efficiency. Since the power line side and the signal line side are separated by the magnetic shield plate, even if noise occurs on the power line side, the noise will not be transmitted to the signal line side.

Since it has a flameproof and explosion-proof structure, even if a spark is emitted from the power line or signal line connection point in a dangerous location such as inside a refueling system filled with vapor, it will not ignite the vapor in the surrounding atmosphere. Safety is ensured.

Further, since the magnetic shield plate is detachably attached, it is possible to enlarge the work space and reduce labor when installing the joint box, connecting (wiring), and performing security work.

Furthermore, vapor is completely prevented from entering the inside of the box through the conductor through-hole. Therefore, it can be suitably applied even to dangerous parts of oil supply equipment where vapor concentration is high.

[Brief explanation of drawings]

FIG. 1 is a front view showing a part of an embodiment of the joint box of the present invention in cross section, and FIG. FIG. 3 is a front view of the oil supply device equipped with the joint box according to the embodiment shown in FIGS. 1 and 2, and FIG. 5 is a front view partially shown in cross section, FIG. 5 is a bottom view of the embodiment, similarly to FIG. 4 partially shown in cross section,
The figure is a front view showing a conventional oil supply device equipped with a joint box. 36,136...Joint Box, 34,
35, 62, 64... Electric conduit, 32, 38... Signal line, 40, 42... Power line, 49... Side wall, 5
0,150...Conductor through hole, 80...Magnetic shield plate, 82,84...Division.

Claims (1)

[Claims] 1. In a joint box with a flameproof explosion-proof structure used in a hazardous area of a refueling system, the inside of the box is divided into a power line side compartment and a signal line side compartment by a removably attached magnetic shield plate,
Two conductive wire through holes are formed on the wall surface of each compartment, and the conductive wire through holes are constituted by a hollow screw adapter that screws into the joint box main body and the conductor pipe. The threaded part between the conductor pipe and the threaded adapter constitutes a seal against vaporized fuel, and two protrusions are formed in the center of each of the opposing side walls of the box body, and the two protrusions are A joint box characterized in that a recess is formed between which the magnetic shield plate is removably disposed.