JP2010043902A - Gas meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To ground an electronic board without spoiling design flexibility, while performing cost reduction with a simple structure. <P>SOLUTION: A gas meter includes an electronic board 41, a case 42, and a metering portion body 21, and has a structure for making the grounding portion of the electronic board 41 conductive electrically with the body 21 to ground the electronic board 41. To acquire the conductive structure on this occasion, a grounding plate 6 for making the grounding portion of the electronic board 41 conductive electrically with the body 21, and screws 5 being fixing members for fixing the electronic board 41 and the case 42 to the body 21, are used. The screws 5 fix the electronic board 41 and one end of the grounding plate 6 in a state that the electronic board 41 is arranged at a predetermined position of the case 42, and the case 42 and the electronic board 41 are fixed to the body 21 in a state that the other end of the grounding plate 6 is in contact with the body 21. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a gas meter, and more specifically, to an electronic gas meter having a function of monitoring an integrated value of gas usage, abnormality information during use, and the like.

  As gas meters, electronic gas meters (microcomputer meters) that monitor the accumulated value of gas usage and abnormal information during use are widespread, and the amount of gas usage is communicated from the gas meter to the gas company using a communication line. Centralized monitoring systems that transmit automatic meter reading data related to integrated values and abnormal information when using gas are also widespread. In such a gas meter, the mechanical movement of the diaphragm is electrically detected by a sensor or the like, and an abnormality such as long-term use of the gas is monitored based on the detection signal.

In the main body of the gas meter, the integrated value is displayed by a numerical wheel linked to the mechanical movement of the diaphragm, and the monitoring information is displayed by a liquid crystal display device.
In addition, as a function to ensure the safety of the gas meter, when the built-in microcomputer determines that gas usage is abnormal during flow rate pulse calculation, or when more signals are input from devices connected to external devices, The microcomputer sends a signal to the shut-off valve drive circuit to drive the shut-off valve, thereby shutting off the gas and displaying abnormal information on the liquid crystal display device. Further, it can be connected to a communication line or a reader to communicate meter reading data and abnormality information.

  Such an electronic gas meter is provided with a main body including a flow rate measuring means for measuring a gas flow rate, a shutoff valve, and the like, and an electronic circuit and a liquid crystal display device for performing various controls and processes of the gas meter such as a shutoff control of the gas. It has an electronic substrate and a case for accommodating the electronic substrate. And the case which accommodated the electronic substrate is being fixed and used for the main body. At this time, the electronic substrate is grounded by connecting the ground portion of the electronic substrate and the main body made of aluminum die casting to form a ground path via the gas pipe.

As an earth structure relating to a gas meter, for example, Patent Document 1 discloses an earth structure of a gas control device built in a gas meter. Here, the circuit board constituting the gas control device is attached to the bracket, and the other end of the ground plate, one end of which can be attached to the fixing part of the bracket to the gas meter main body, is fixed to the grounding part of the circuit board. Later, by coating the circuit board, the ground path from the circuit board of the gas control device is surely formed to the ground through the ground plate, gas meter, and gas pipe regardless of the coating process of the circuit board. I have to.
JP 2000-146659 A

In a conventional electronic gas meter, a sheet metal part is used to connect an electronic board and an aluminum die-cast body, and the grounding part of the electronic board and the sheet metal part are connected using a conductive wire, and the sheet metal part and aluminum The main body made of die-casting is fixed with a fixing member to make them conductive, thereby grounding.
However, in such a conventional configuration, the number of parts is increased by using the conducting wire, and the number of steps for assembling the conducting wire is increased, resulting in high cost. Furthermore, there is a problem in that the components around the portion where the conductive wire is arranged must be in the shape of a component in consideration of the winding of the conductive wire, and the degree of freedom in design is low. Patent Document 1 does not disclose a configuration related to the grounding of the electronic board of such an electronic gas meter.

  The present invention has been made in view of the above circumstances, and an object of the present invention is to provide a gas meter capable of reducing the cost with a simple structure and grounding an electronic board without impairing the degree of freedom of design. Is.

  In order to solve the above-mentioned problem, the invention of claim 1 includes an electronic board, a case to which the electronic board is attached, and a weighing unit main body to which the case is attached together with the electronic board, and grounds the electronic board. In the gas meter having a structure for electrically connecting the grounding part of the electronic substrate and the weighing unit main body, a ground plate for conducting the grounding part of the electronic substrate and the weighing unit main body, and the electronic substrate, A fixing member for fixing the case to the main body of the measuring unit, and the fixing member integrates the electronic substrate, the case, and the ground plate in a state where the electronic substrate is disposed at a predetermined position of the case. And the case, the electronic substrate, and the measuring unit main body are fixed in a state where the other end of the ground plate is in contact with the measuring unit main body. A.

  According to a second aspect of the invention, in the first aspect of the invention, the fixing member is a screw, and a screw hole is provided at one end of the ground plate, and the screw is screwed into the screw hole. The electronic substrate, the case, and the ground plate are integrally fixed, and the case, the electronic substrate, and the measuring unit main body are fixed by screwing the screw into the measuring unit main body. It is characterized by being.

  According to the present invention, it is possible to provide a gas meter capable of reducing the cost with a simple structure and grounding the electronic board without impairing the degree of freedom of design.

  FIG. 1 is a perspective view showing an external configuration example of a gas meter according to the present invention, in which 1 is a gas meter, 2 is a main body, 3 is an upper cover, and 4 is a lower cover. The main body 2 is formed of aluminum die casting, and houses a diaphragm type flow rate measuring means, a shut-off valve, and the like. Further, a mechanical counter is housed in the upper cover 3, and the gas flow rate measured by the flow rate measuring means is displayed. Further, inside the lower cover 4 is housed an electronic board equipped with an electronic circuit and a liquid crystal display device for performing various controls and processes of the gas meter such as gas cutoff control. The mechanical counter in the upper cover 3 displays the integrated value by a numeral wheel linked to the mechanical movement of the diaphragm, and the liquid crystal display device in the lower cover 4 displays the monitoring information output from the security unit on the electronic board. Display and display alarms.

FIG. 2 is an exploded perspective view of the inside of the lower cover of the gas meter. In the figure, reference numeral 41 denotes an electronic circuit board equipped with an electronic circuit and a liquid crystal display device for performing various controls and processes of the gas meter, and 42 holds the electronic circuit board 41. It is a case.
The electronic board 41 is attached to the measuring unit main body which is a lower structure of the main body 2 in FIG. 1 while being fixed to the case 42. The lower cover 4 is attached to the case 42 so as to protect the case 42 and the electronic substrate 41.

FIG. 3 is a diagram for explaining a structure for fixing the electronic substrate and the case to the measuring unit main body. In the figure, 5 is a screw, 6 is a ground plate, 61 is a screw hole provided in the ground plate, and 21 is a weighing unit. The main body 411 is a through hole provided in the electronic substrate, the reference numeral 421 is a through hole provided in the case, and the reference numeral 422 is a protrusion provided in the case.
The measuring unit main body 21 is a lower structure of the main body 2 in FIG. 1 and includes a flow rate measuring means using a diaphragm. The weighing unit main body 21 is made of aluminum die casting, and an electronic substrate 41 and a case 42 are attached to the weighing unit main body 21. The circuit components on the electronic board 41 are not shown.

  In the configuration according to the present embodiment, the screw 5 is used as a fixing member for fixing the electronic substrate 41 to the case 42, and the electronic substrate 41 and the case 42 are fixed to the measuring unit main body 21 with the same screw 5. At this time, the screw 5 is fixed so that one end of the ground plate 6 is electrically connected to the ground portion of the electronic substrate 41, and the other end of the ground plate 6 is in contact with the measuring unit main body 21. Thereby, the electronic board 41 and the measuring unit main body 21 are electrically connected by the ground plate 6, and the electronic substrate 41 is grounded via the gas pipe connected to the measuring unit main body 21.

  Here, when attaching the case 42 and the electronic substrate 41 to the measuring unit main body 21, first, the screw 5 is passed through one of the through holes 411 provided in the electronic substrate 41, and further the through hole 421 of the case 42. The electronic board 41 is arranged at a predetermined position in the case 42 through the screw 5. Further, the other through-hole 411 of the electronic substrate 41 is fitted into a protrusion 422 provided in the case 42, whereby the electronic substrate 41 is positioned.

  At this time, the ground plate 6 having the screw hole 61 at one end is disposed on the back side of the case 42 (on the weighing unit main body 21 side), and the screw 5 is screwed into the screw hole 61 of the ground plate 61. Thereby, the electronic substrate 41, the case 42, and the ground plate 6 are fixed integrally. At this time, the ground portion of the electronic substrate 41 and the ground plate 6 are electrically connected by configuring the one end portion of the ground plate and the ground portion of the electronic substrate 41 to contact each other.

  Furthermore, the case 42 is attached and fixed to the measuring unit main body 21 using the same screw 5. The measuring unit main body 21 can be fixed with the screw 5 by providing a screw hole into which the screw 5 is screwed. At this time, the case 42 and the electronic substrate 41 are fixed to the measuring unit main body 21 with the other end of the ground plate 6 in contact with the measuring unit main body 21. Thereby, the grounding part of the electronic substrate 41 and the measuring part main body 21 are electrically connected via the grounding plate 6. Then, the ground path of the electronic substrate 41 reaches the ground via the gas pipe connected to the measuring unit main body 21, and the grounding of the electronic substrate 41 is established.

  In the above embodiment, the screw 5 is used as the fixing member. However, as the fixing member for fixing the electronic board 41 and the case 42 to the measuring unit main body 21 together with the ground plate 6, a known member other than the screw is appropriately used. May be. For example, rivets or pins can be used. Or the structure using a volt | bolt and a nut may be sufficient.

  According to the configuration as described above, since the ground plate 6 is in direct contact with the ground portion of the electronic substrate 41 and the measuring unit main body 21, the number of parts for making the electronic substrate 41 and the main body 21 conductive is reduced. As a result, the cost can be reduced. Further, the ground plate 6 may have any shape as long as a conductive structure between the electronic substrate 41 and the measuring unit main body 21 can be realized, and an allowable range such as a fixing method and a fixing place of the ground plate 6 is widened. The degree of freedom in designing the parts can be improved.

It is a perspective view which shows the example of an external appearance structure of the gas meter of this invention. It is a disassembled perspective view of the inside of the lower cover of a gas meter. It is a figure for demonstrating the structure which fixes an electronic substrate and a case to a measurement part main body.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 ... Gas meter, 2 ... Main body, 3 ... Upper cover, 4 ... Lower cover, 5 ... Screw, 6 ... Ground plate, 21 ... Measuring body, 41 ... Electronic board, 42 ... Case, 61 ... Screw hole, 411 ... Through Hole, 421 ... through hole, 422 ... projection.

Claims (2)

An electronic substrate; a case to which the electronic substrate is attached; and a weighing unit body to which the case is attached together with the electronic substrate; and a grounding unit of the electronic substrate and the weighing unit body for grounding the electronic substrate. In a gas meter with a structure for conducting
A grounding plate for conducting the grounding part of the electronic substrate and the weighing unit body;
A fixing member for fixing the electronic substrate and the case to the measuring unit main body;
The fixing member integrally fixes the electronic substrate, the case, and the ground plate in a state where the electronic substrate is disposed at a predetermined position of the case, and the other end portion of the ground plate is the weighing unit. The gas meter, wherein the case, the electronic substrate, and the measuring unit main body are fixed in contact with the main body.   2. The gas meter according to claim 1, wherein the fixing member is a screw, and a screw hole is provided in one end portion of the ground plate, and the screw is inserted into the screw hole, whereby the electronic board is provided. The case, the grounding plate are fixed integrally, and the case, the electronic substrate, and the measuring unit main body are fixed by screwing the screw into the measuring unit main body unit. A characteristic gas meter.

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