JP7521987B2 - Water meter transmitter and water meter system - Google Patents

Description

The present invention relates to a water meter transmitter that is connected to a water meter via a communication cable, and a water meter system in which the water meter transmitter is connected to the water meter via a cable.

Water meters are generally used by connecting them in a horizontal position to a section of a horizontally placed water pipe. For example, they are used by connecting them to a water pipe in a meter box buried underground. A known water meter is an electronic water meter that has an electronic measuring unit in the meter case that houses electronic components for measuring flow rate (Patent Document 1).

A known method of reading electronic water meters is a system that uses a specific low-power radio to collect meter reading data (measurement data) in a non-contact manner. In this meter reading system, a wireless slave unit is connected to each water meter installed at the point of use via a communication cable. When the wireless master unit connected to the transmission device requests meter reading data from each wireless slave unit, in response, the wireless slave unit transmits the measurement data stored in the electronic water meter. Each measurement data collected by the wireless master unit is read into a management computer (not shown) via the transmission device and is collected there (Patent Document 2).

Meanwhile, there is a known electronic water meter reading system in which the meter reading data from each water meter is collected directly to a meter reading center terminal via a PHS, a regular telephone line, an IP network, or a CATV network (see the background art section of Patent Document 3). In this system, too, each water meter is equipped with wireless communication capabilities, or a transmitter is connected to the water meter via a communication cable.

JP 2002-340634 A JP 2002-150463 A JP 2020-063941 A

In order to use the above-mentioned meter reading system to perform meter reading, etc., a water meter that does not have a communication function is generally connected to a water meter transmitter via a communication cable. For example, a water meter transmitter is connected to a water meter attached to a water pipe inside a meter box via a communication cable, and in this state the water meter transmitter is installed inside the meter box.

In this case, the water meter transmitter is generally placed at the bottom of the meter box while connected to the water meter by a cable, and its position, orientation, and posture are indefinite. Furthermore, the excess cable is left bundled inside the narrow meter box. The transmitter and cable may become buried in water or mud that has seeped into the meter box, which may accelerate their deterioration. Furthermore, if the water meter transmitter and cable are buried in water or mud and the position of the water meter transmitter is indefinite, for example, in a water meter transmitter equipped with a directional antenna, the directional antenna may be pointed in an inappropriate direction or may be affected by the cable, water, mud, etc., causing communication failure and preventing automatic meter reading operations via wireless communication.

On the other hand, even when a water meter transmitter is connected to a water meter installed on the ground via a cable, the water meter transmitter may hang from the water meter by the cable, and the excess cable may end up being bundled in a messy manner. In addition, the position, direction, and posture of the transmitter may become unstable, and the built-in directional antenna may not be able to be maintained in a state with good reception sensitivity by pointing in the appropriate direction.

In view of the above, the object of the present invention is to provide a water meter transmitter that eliminates excess length in the communication cable connecting the water meter and that can maintain the position and orientation of the water meter transmitter, which is suspended from the cable relative to the water meter, in an appropriate state, and a water meter system that includes the water meter transmitter.

In order to solve the above problems, the water meter transmitter of the present invention comprises:
A wired communication unit that communicates with the water meter via a communication cable;
A wireless communication unit that performs wireless communication with an external device;
a transmitter case having the wired communication unit and the wireless communication unit built therein;
a cable storage section provided in the transmitter case for storing an excess portion of the cable;
The present invention is characterized in that it has the following features.

After connecting the water meter and water meter transmitter with a cable, the excess cable can be stored in the cable storage section of the water meter transmitter. The length of the cable pulled out of the cable storage section (the length of the cable stretched between the water meter and the water meter transmitter) can be set to an appropriate length. This eliminates the need to bundle the excess cable so that it does not get in the way, and there is no need to reserve space for the excess cable in a small installation space.

The position and orientation of a water meter transmitter that is hung from a water meter, placed on a water meter, or hung on a wall, etc., can be regulated to some extent by a cable that is stretched without any excess length. The length of the cable that is pulled out is appropriately determined, and the position and direction of the cable pulled out from the cable storage section are appropriately determined in relation to the center of gravity of the water meter transmitter. This makes it possible to restrain the position and orientation of the water meter transmitter that is hung from a water meter, placed on a water meter, or hung on a wall, etc., from changing by the cable.

In particular, if the wireless communication unit is equipped with a directional antenna, the water meter transmitter must be installed so that the directional antenna faces the appropriate direction. The cable pull-out length is set appropriately, and the pull-out position and pull-out direction of the cable pulled out from the cable storage unit are determined in advance relative to the center of gravity of the water meter transmitter. This allows the water meter transmitter to be installed in a position and orientation that provides good reception sensitivity. The cable also holds the water meter transmitter in place so that its installation position and orientation do not change.

By using the water meter system of the present invention, which includes a water meter transmitter, a communication cable, and a water meter, the water meter transmitter can be neatly stored in a limited installation space, such as inside a meter box, by connecting it to the water meter via a cable. It is also possible to prevent the water meter transmitter and cable from being placed at the bottom of the meter box and becoming buried in water, mud, etc. Furthermore, the position and orientation of the water meter transmitter can be regulated by the cable with a certain degree of restraint, thereby avoiding communication failures.

1 is an explanatory diagram showing an example of a meter reading system including a water meter transmitter to which the present invention is applied; 1A and 1B are plan and side views showing a water meter. 1A and 1B are an external perspective view, a schematic vertical sectional view, and a schematic horizontal sectional view of a water meter transmitter. 1A and 1B are a plan view and a side view showing a water meter transmitter attached to a water meter. FIG. 11 is an external perspective view showing another example of a water meter transmitter. 13A and 13B are side and bottom views showing yet another example of a water meter transmitter. 1A to 1C are explanatory diagrams showing two examples of installation states of a water meter transmitter.

Below, an embodiment of a water meter transmitter to which the present invention is applied will be described with reference to the drawings. Note that the embodiment described below is merely an example of the present invention, and is not intended to limit the present invention to the configuration of the embodiment.

Figure 1 is a conceptual diagram showing an example of an automatic water meter reading system equipped with a water meter transmitter to which the present invention is applied. The water meter system installed at each water usage location is configured with a water meter transmitter 3 connected to an electronic water meter 1 via a communication cable 2. The water meter transmitter 3 is connected to a management server 5 of a management company via a communication line network 4 such as an LTE network. Each water supplier communicates with the management server 5 via a communication terminal 6 such as a PC. The meter reading value of the water meter 1 is transmitted to the management server 5 via the water meter transmitter 3 periodically or in response to a request from the management server 5. The management server 5 of the management company performs meter reading, water billing and collection on behalf of each water supplier, and the same is done by the communication terminal 6 such as a PC of the water supplier.

At each water usage location, the water meter 1 is used by connecting it to a horizontally extending water pipe 8 inside a meter box 7 installed, for example, underground. In this case, the water meter transmitter 3 is also stored in the meter box while connected to the water meter 1 via a cable 2.

2(a) is a plan view showing an example of a water meter 1, and FIG. 2(b) is a side view of the water meter 1. The water meter 1 is equipped with a meter case 11 connected between water pipes 8, and the inside of the central part of the meter case 11 is a measuring chamber 12 for measuring the flow rate. The central part of the meter case 11 is formed with a cylindrical part 18 that protrudes upward. From the upper end opening of the cylindrical part 18, a measuring unit 13 composed mainly of a computer is housed inside. A liquid crystal display part 14 is disposed at the upper end of the measuring unit 13. A circular flange 19 is attached to the upper end edge of the cylindrical part 18, and the measuring unit 13 and the liquid crystal display part 14 are fixed by the flange 19 so that they do not come out of the cylindrical part 18. Four ribs 19a protrude at 90 degree intervals from the circular outer peripheral surface of the flange 19. In addition, a meter cover 15 is attached so as to cover the display surface of the liquid crystal display part 14.

As shown by the dashed line in FIG. 2(a), a terminal cover 17 that covers the external output terminal 16 is attached adjacent to the display surface of the liquid crystal display unit 14 covered by the meter cover 15. One end 21 of the communication cable 2 is connected to the external output terminal 16. After being pulled out from the side of the terminal cover 17, the cable 2 is pulled out to the outside through a U-shaped groove formed in the side of the meter cover 15.

Figure 3(a) is an external view showing an example of a water meter transmitter 3, Figure 3(b) is a schematic vertical cross-sectional view, and Figure 3(c) is a schematic horizontal cross-sectional view. The water meter transmitter 3 (hereinafter sometimes simply referred to as "transmitter 3") has a waterproof transmitter case 31 made of a disk-shaped plastic molded product or the like. Inside this transmitter case 31 are built a communication control unit 32, which is mainly composed of a computer, a wired communication unit 33, a wireless communication unit 34, and a battery power source 35.

The wired communication unit 33 inside the transmitter case 31 has an external output terminal 36, to which the other end 22 of the cable 2 is connected. The communication unit 33 communicates messages with the measurement unit 13 of the water meter 1 via the cable 2. The wireless communication unit 34 has a communication board 37 on which communication electronic components, circuits, and a wireless communication module are mounted, a directional antenna 38 for wireless communication, and the like. The communication unit 34 communicates with external devices via a wireless communication line network such as an LTE network.

A cable winding section 40 that functions as a cable storage section is attached to the outer peripheral surface of the transmitter case 31. The cable winding section 40 has a cylindrical outer case 41 that is rotatably attached to the transmitter case 31 around its central axis 3a. This outer case 41 covers the entire circumference of the circular outer peripheral surface 31a of the transmitter case 31. An annular cable winding space 42 is formed between the circular inner peripheral surface 41a of the outer case 41 and the circular outer peripheral surface 31a of the transmitter case 31. This cable winding space 42 is a space with a constant radial thickness and a constant width in the height direction along the central axis 3a.

A cable passage hole 43 is formed in the outer case 41, connecting the cable winding space 42 with the outside. The cable passage hole 43 opens radially outward at the upper end of the circular outer peripheral surface of the outer case 41. A cable passage hole 44 is also formed in the circular outer peripheral surface 31a of the inner transmitter case 31. The cable passage hole 44 opens at a portion of the circular outer peripheral surface 31a of the transmitter case 31 that faces the external output terminal 36.

One end 21 of the end 22 of the cable 2 is connected to the external output terminal 16 on the water meter 1 side, and the cable 2 is pulled out from the external output terminal 36 of the transmitter 3 through the cable passage hole 44 of the transmitter case 31 into the cable winding space 42, and from there it is pulled out to the outside through the cable passage hole 43 of the outer case 41 and connected to the water meter 1 side. The space between the cable passage hole 44 and the cable 2 is kept liquid-tight by a sealant or the like.

When the upper end surface 31b and the lower end surface 31c of the transmitter case 31 are held and the outer case 41 is rotated around the central axis 3a, the cable 2 is pulled into the cable winding space 42 from the outer cable through hole 43 and wound around the circular outer circumferential surface 31a of the transmitter case 31. This allows the portion of the cable pulled out from the cable through hole 43 to be set to an appropriate length, and the cable 2 can be stretched between the water meter 1 and the transmitter 3 with no excess length. After the cable pull-out length has been determined, the outer case 41 is fixed to the transmitter case 31 by a fixing bracket such as a screw (not shown) or a rotation prevention mechanism. This fixes the cable pull-out length and pull-out position.

Figure 4(a) is a plan view showing an example of the state in which the cable pull-out length is set in this way and the transmitter 3 is installed on the top side of the water meter 1, and Figure 4(b) is a side view of the same. For example, the transmitter 3 is held leaning at an angle against the top side of the meter case 11 of the water meter 1. The length of the cable 2 connecting the water meter 1 and the transmitter 3 is the minimum required length, and the excess length of the cable 2 is wound around the cable winding section 40. With the cable 2 stretched in a predetermined tension state, the transmitter 3 is held leaning at an angle against the top side of the water meter 1 with its upper end surface 31b facing diagonally upward.

In the cable winding section 40 of the transmitter 3, the cable 2 is wound around the central axis 3a extending in the vertical direction of the transmitter 3. The cable through hole 43 of the transmitter 3 is formed on the circular outer circumferential surface of the disk-shaped transmitter 3, and the cable 2 is pulled out from the cable through hole 43 radially outward in a direction perpendicular to the central axis 3a. In this example, each part is arranged so that the center of gravity of the transmitter 3 is located on the central axis 3a. The transmitter 3 is pressed against the water meter 1 by its own weight and is held in a position leaning diagonally by the cable 2. The direction of the directional antenna 38 of the wireless communication section of the transmitter 3 is set to a direction parallel to the central axis 3a. The transmitter 3 is held in a state in which the direction of the antenna faces diagonally upward, ensuring the required reception sensitivity. Also, unlike when the transmitter 3 is left at the bottom of the meter box 7, the transmitter and cable will not become buried in water, mud, etc. that has entered the meter box 7.

(Another example of a water meter transmitter)
5 is an external perspective view showing a transmitter equipped with a cable winding section having a structure different from that of the cable winding section 40 described above. The cable winding section 140 of the transmitter 3A shown in this figure has a circular outer peripheral surface of a disk-shaped transmitter case 141, on which a cable winding groove 142 having a rectangular cross section is formed over the entire circumference. The cable winding groove 142 opens radially outward on the circular outer peripheral surface. The cable winding section 140 also has a cable fixing section 143 that fixes the cable 2 wound in the cable winding groove 142 so that it does not come off the groove, and determines the position where the cable is pulled out from the cable winding groove 142. The cable fixing section 143 has a cable tie 144 and a pair of band passing holes 145, 146 formed above and below the cable winding groove 142 in the transmitter case 141.

The excess length of cable 2 is wound around cable winding groove 142, and the required length of cable 2 is pulled out from the area where band-passing hole 145 is located. In this state, cable ties 144 are passed through band-passing holes 145 and 146, and the portion of cable 2 wound up with cable ties 144 is bundled together. This fixes the length and position of the cable pull-out.

Figure 6(a) is a side view of a transmitter 3B with a cable winding section of yet another configuration, and Figure 6(b) is a bottom view of the same. The transmitter 3B has a disk-shaped transmitter case 241. A cable winding reel 243 is attached coaxially to the circular lower end surface 241c of the transmitter case 241. The cable winding reel 243 has a cylindrical winding core 244 attached coaxially to the lower end surface 241c, and an annular flange 245 attached coaxially to its lower edge. In addition, a cable passage groove 246 is formed on the outer peripheral edge side of the lower end surface 241c, into which the cable 2 can be inserted with a predetermined restraining force.

The excess length of cable 2 that is pulled out from the external connection terminal of transmitter 3B and connected to water meter 1 is wound up on cable winding reel 243. The portion of cable 2 that is pulled out from cable winding reel 243 is pulled outward through cable guide groove 246. This fixes the length of the cable pull-out and the position and direction of the cable pull-out.

Figure 7 is an explanatory diagram showing an example of transmitter installation different from the above. For example, the transmitter 3 shown in Figure 4 can be installed in a state of being suspended by the cable 2 on the side of the meter case 11 as shown in Figure 7 (a). In this case, the center of gravity of the transmitter 3 is located at its center O, and the direction of the directional antenna (not shown) is set to the diameter direction of the transmitter case 31 as shown by arrow A. In addition, the direction of the arrow A is set to extend at a predetermined angle, for example, 45°, diagonally upward with respect to the diameter line connecting the center of gravity position (O) and the cable extraction position B. In this way, if the center of gravity position (O), the cable extraction position B, and the direction of the direction (A) are set, the position and orientation (posture) of the transmitter 3 are determined so that the directional antenna faces the direction of the direction of the direction when the transmitter 3 is suspended by the cable 2.

For example, the transmitter 3 can be restrained using two of the four ribs 19a formed at 90 degree intervals on the circular outer periphery of the annular flange 19 attached to the upper edge of the cylindrical section 18 extending upward from the center of the meter case 11. As shown in the figure, the transmitter 3 is suspended so that it is sandwiched between the two ribs 19a that are spaced 90 degrees apart. The cable 2 pulls the transmitter 3 up so that it is pressed against the two ribs 19a from below. This allows the transmitter 3 to be suspended in a fixed position without swinging up, down, left or right.

Also, as shown in FIG. 7(b), the cable 2 can be hung from a wall or the like near the water meter 1 using metal fittings C, and the transmitter 3 can be installed in a suspended state. In this case, the position and orientation (posture) of the transmitter 3 are also determined. Therefore, the communication state of the installed transmitter 3 can be maintained in an appropriate state.

(Other embodiments)
(1) In each of the above examples, a cable winding section is used as the cable storage section. In some cases, the cable may be stored in a bundled state without being wound up in the cable storage section provided inside the transmitter case.
(2) The transmitter case may have various shapes instead of a disk shape. For example, the transmitter case may have a flat or cylindrical shape. For example, the transmitter case may have a cylindrical shape with a polygonal outline, such as a flat rectangular cylindrical shape, and the outer circumferential surface of the cylindrical shape may be used as a cable winding portion.
(3) The cable fixing section, which fixes the wound cable on the cable winding section so that it does not come off and determines the length, position or direction of the cable being pulled out from the cable winding section, can have a variety of structures.

1 Water meter 2 Cable 3 Water meter transmitter (transmitter)
Reference Signs List 3a Central axis 3A, 3B Transmitter 4 Communication line network 5 Management server 6 Communication terminal 7 Meter box 8 Water pipe 11 Meter case 12 Metering chamber 13 Measurement unit 14 Liquid crystal display unit 15 Meter cover 16 External output terminal 17 Terminal cover 18 Cylindrical portion 19 Flange 19a Rib 21, 22 End portion 31 Transmitter case 31a Circular outer peripheral surface 31b Upper end surface 31c Lower end surface 32 Communication control unit 33 Communication unit 34 Communication unit 35 Battery power source 36 External output terminal 37 Communication board 38 Directional antenna 40 Cable winding portion 41 Outer case 41a Circular inner peripheral surface 42 Cable winding space 43, 44 Cable through hole 140 Cable winding portion 141 Transmitter case 142 Cable winding groove 143 Cable fixing portion 144 Cable ties 145, 146 Cable passage hole 241 Transmitter case 241c Bottom end surface 243 Cable winding reel 244 Winding core 245 Flange 246 Cable passage groove A Arrow (pointing direction)
B Cable pull-out position C Metal fitting O Center (center of gravity)

Claims (9)

A wired communication unit that communicates with the water meter via a communication cable;
A wireless communication unit that performs wireless communication with an external device;
a transmitter case having the wired communication unit and the wireless communication unit built therein;
a cable storage section provided in the transmitter case for storing an excess portion of the cable;
It has
so that the position and orientation of the transmitter case while suspended by the cable are in a predetermined position and orientation,
A water meter transmitter in which the length of the cable pulled out from the cable storage section and the position or direction of the cable pulled out from the cable storage section relative to the center of gravity position of the water meter transmitter are determined . In claim 1,
The wireless communication unit includes a directional antenna,
A water meter transmitter in which the pull-out position or pull-out direction relative to the center of gravity position is determined so that the directional antenna faces the direction of its direction of orientation . In claim 1 ,
the transmitter case is a flat cylindrical case,
The cable storage section includes:
a cable winding section having a winding center line aligned with a central axis of the transmitter case;
A water meter transmitter comprising a cable fixing part which determines the length and the position or direction of the cable pulled out from the cable winding part . In claim 3 ,
The wireless communication unit includes a directional antenna,
A water meter transmitter , wherein the direction of the directional antenna is parallel to the central axis of the transmitter case . In claim 3 or 4,
the transmitter case is a disc-shaped case,
the cable winding portion includes an annular cable winding groove formed around the entire circumference of the outer circumferential surface of the transmitter case,
A water meter transmitter , wherein the cable winding groove opens radially outward from the outer circumferential surface of the transmitter case . In claim 3 or 4,
the transmitter case is a disc-shaped case,
the cable winding section includes a cylindrical outer case attached to the transmitter case so as to be rotatable about the central axis,
the outer case covers all or a part of an outer circumferential surface of the transmitter case,
an annular cable winding space is formed between an inner peripheral surface of the outer case and an outer peripheral surface of the transmitter case,
The outer case is formed with a cable passage hole that connects the cable winding space to the outside.
It has been
A water meter transmitter in which, when the outer case is rotated in one direction, the cable can be pulled into the cable winding space from the cable passing hole and wound around the outer circumferential surface of the transmitter case, and, when the outer case is rotated in the reverse direction, the cable can be pulled out to the outside through the cable passing hole . In claim 3 or 4,
the transmitter case is a disc-shaped case,
The cable winding section of the water meter transmitter is provided with a cable winding reel attached to the upper end surface or the lower end surface of the transmitter case. An electronic water meter,
A water meter transmitter;
a communication cable connecting the water meter and the water meter transmitter;
It is equipped with
8. A water meter system, wherein the water meter transmitter is the water meter transmitter according to claim 1 . 9. The water meter system according to claim 8,
A meter box is provided in which the water meter is housed,
A water meter system in which the water meter transmitter is disposed inside the meter box while being connected by the cable .

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