JP2010008116A

JP2010008116A - Gas meter

Info

Publication number: JP2010008116A
Application number: JP2008165283A
Authority: JP
Inventors: Yasuhiro Matsumoto; 安浩松本; Takahiro Ogusu; 貴宏小楠; Kazuhiro Ushijima; 一博牛嶋
Original assignee: Yazaki Corp
Current assignee: Yazaki Corp
Priority date: 2008-06-25
Filing date: 2008-06-25
Publication date: 2010-01-14
Anticipated expiration: 2028-06-25
Also published as: JP5166989B2

Abstract

PROBLEM TO BE SOLVED: To provide a gas meter capable of measuring accurate flow velocity even in a high flow rate zone. SOLUTION: A U-shaped channel communicated with a gas outflow port is provided from a gas inflow port. The channel is constituted of an inlet channel part 3A along a vertical direction communicated with the gas inflow port, an outlet channel part along a vertical direction communicated with the gas outflow port, and a measuring channel part along a horizontal direction provided between the inlet channel part 3A and the outlet channel part. A flow velocity sensor is provided on the measuring channel part. A straightening vane 7 is provided in the horizontal direction on a connection part with the measuring channel part of the inlet channel part 3A. The straightening vane 7 is provided with a first projection part 7A projecting toward the gas outflow port side from the rearmost surface side of the end on the gas outflow port side. The straightening vane 7 is also provided with a second projection part 7B projecting toward the gas outflow port side from the foreground surface side of the end on the gas outflow port side. COPYRIGHT: (C)2010,JPO&INPIT

Description

本発明は、ガスメータに係り、特に、ガス流入口とガス流出口との間を連通する流路に流速センサが配置されたガスメータに関するものである。 The present invention relates to a gas meter, and more particularly to a gas meter in which a flow rate sensor is disposed in a flow path communicating between a gas inlet and a gas outlet.

従来から、図９（Ａ）に示すように、メータボディ（図示せず）に設けられたガス流入口２Ａとガス流出口２Ｂとの間を連通する流路３を通過するガスの流量を検出するガスメータ１が知られている（例えば特許文献１）。上記流路３は、入口流路部３Ａと、出口流路部３Ｂと、計測流路部３Ｃと、から構成されていて、Ｕ字状に折れ曲がっている。入口流路部３Ａは、ガス流入口２Ａと連通すると共に鉛直方向に沿うように設けられている。出口流路部３Ｂは、ガス流出口２Ｂと連通すると共に鉛直方向に沿うように設けられている。計測流路部３Ｃは、入口流路部３Ａ及び出口流路部３Ｂ間に水平に沿うように設けられている。この計測流路部３Ｃ内には、複数の整流板９が配置され、この整流板９の近傍にはガスの流速を検出するための流速センサ（図示せず）が配置されている。そして、流速センサとしての一対の超音波振動子の間の超音波の伝搬速度を利用して、流量計測が行われる。 Conventionally, as shown in FIG. 9A, the flow rate of gas passing through a flow path 3 communicating between a gas inlet 2A and a gas outlet 2B provided in a meter body (not shown) is detected. A gas meter 1 is known (for example, Patent Document 1). The flow path 3 includes an inlet flow path section 3A, an outlet flow path section 3B, and a measurement flow path section 3C, and is bent in a U shape. The inlet channel portion 3A communicates with the gas inlet 2A and is provided along the vertical direction. The outlet channel portion 3B communicates with the gas outlet 2B and is provided along the vertical direction. The measurement flow path portion 3C is provided so as to extend horizontally between the inlet flow path portion 3A and the outlet flow path portion 3B. A plurality of rectifying plates 9 are arranged in the measurement flow path portion 3C, and a flow velocity sensor (not shown) for detecting the gas flow velocity is arranged in the vicinity of the rectifying plates 9. And flow measurement is performed using the propagation speed of the ultrasonic wave between a pair of ultrasonic transducers as a flow velocity sensor.

この流量計測では、ガスの流れ(単にガス流とも呼ぶ)と超音波伝搬経路のなす角をθとし、一対の超音波振動子間のガス流れ方向の長さをＬとすると、上流方向への超音波の伝搬時間Ｔ１及び下流方向への超音波の伝搬時間Ｔ２に基づいて、流速Ｖ＝Ｌ／２ｃｏｓθ（１／Ｔ１−１／Ｔ２）を求めることができる。従って、流量＝ＫＶＳとして求めることができる。ここで、Ｓは計測流路部３Ｃの断面積であり、Ｋは流速Ｖを断面積Ｓにおける平均流速に変換するときの変換係数である。 In this flow measurement, if the angle between the gas flow (also simply referred to as the gas flow) and the ultrasonic propagation path is θ and the length in the gas flow direction between the pair of ultrasonic transducers is L, Based on the ultrasonic wave propagation time T1 and the ultrasonic wave propagation time T2 in the downstream direction, the flow velocity V = L / 2 cos θ (1 / T1-1 / T2) can be obtained. Therefore, it can obtain | require as flow volume = KVS. Here, S is a cross-sectional area of the measurement flow path portion 3C, and K is a conversion coefficient when the flow velocity V is converted into an average flow velocity in the cross-sectional area S.

上記構成のガスメータ１において、図９（Ａ）中、太矢印で示すように、ガス流入口２Ａに流入してきたガスは、細矢印で示すように、入口流路部３Ａを通過して計測流路部３Ｃに流入する。そして、ガスは、計測流路部３Ｃ内の整流板９にて整流され、上記計測方法を利用して流量計測され、出口流路部３Ｂを通過し、ガス流出口２Ｂから流出していく。 In the gas meter 1 having the above configuration, as shown by a thick arrow in FIG. 9A, the gas flowing into the gas inlet 2A passes through the inlet channel portion 3A as shown by the thin arrow, and the measured flow It flows into the road portion 3C. Then, the gas is rectified by the rectifying plate 9 in the measurement flow path portion 3C, the flow rate is measured using the measurement method, passes through the outlet flow path portion 3B, and flows out from the gas outlet 2B.

また、組立工数削減のために、図１０に示すように、遮断弁５をガスメータ１本体の正面から取り付ける構造が提案されている。このため、ガス流入口２Ａから流入したガスが、まっすぐ下方に降りて計測流路部３Ｃに入ることができない。なお、図１０中の矢印はガスの流れを示す。また、矢印の太さが太いほどガスの流れが速いことを示す。 In order to reduce assembly man-hours, as shown in FIG. 10, a structure in which the shut-off valve 5 is attached from the front of the gas meter 1 main body has been proposed. For this reason, the gas flowing in from the gas inlet 2A cannot go straight down and enter the measurement flow path portion 3C. In addition, the arrow in FIG. 10 shows the flow of gas. Also, the thicker the arrow, the faster the gas flow.

詳しく説明するとガス流入口２Ａから流入したガスは、遮断弁５の部分で一度ガスメータ１の背面へ流れ、ガスメータ１の背面をたどって下降し、ガスメータ１の背面から計測流路部３Ｃに流れるという複雑な流れとなった。よって、図中の太矢印に示すように計測流路部３Ｃにおいて背面側はガスの流れが速く、図中の細矢印に示すように正面側はガスの流れが遅い。即ち、計測流路部３Ｃ内においては、図１１（Ａ）に示すように、正面側と背面側とでガスの流量差がないのが理想的である。しかしながら、上述したように遮断弁５をガスメータ１本体の正面から取り付ける構造にすると、図１１（Ｂ）に示すように、計測流路部３Ｃ内においては、背面側のガス流量が正面側のガス流量より大きくなり、正面側と背面側とでガスの流量差が生じてしまう。このような計測流路部３Ｃ内でのガス流速（流量）の偏りは、ガスの流量が少ないときは問題がない。 More specifically, the gas flowing in from the gas inlet 2A once flows to the back surface of the gas meter 1 at the shut-off valve 5 portion, descends along the back surface of the gas meter 1, and flows from the back surface of the gas meter 1 to the measurement flow path portion 3C. It became a complicated flow. Therefore, as shown by the thick arrow in the figure, the gas flow is fast on the back side in the measurement flow path portion 3C, and the gas flow is slow on the front side as shown by the thin arrows in the figure. That is, in the measurement flow path section 3C, it is ideal that there is no gas flow rate difference between the front side and the back side, as shown in FIG. However, when the shut-off valve 5 is mounted from the front of the gas meter 1 body as described above, the back side gas flow rate is the front side gas flow rate in the measurement flow path section 3C as shown in FIG. It becomes larger than the flow rate, and a gas flow rate difference occurs between the front side and the back side. Such a deviation in the gas flow velocity (flow rate) in the measurement flow path portion 3C is not problematic when the gas flow rate is small.

しかしながら、ガスの流量が増加し、流速が早くなるに従って、上述した計測流路部３Ｃ内でのガス流速の偏りは大きくなる。そして、ある一定流量（例えば、６０００〜８０００Ｌ／ｈ）を越えると、計測流路部３Ｃ内で局所的に強い乱流（渦）が発生し、圧力損失が急に増加するという不具合が発生する。つまり、ある一定流量以上の領域では、図１２に示すように、流量係数（器差補正係数）を非常に大きくしないと、正しい流量が計測できなくなる。そればかりか、この一定流量以上の領域では、流量計測値のバラつきが大きく、流量誤差が大きくなってしまう、という問題があった。 However, as the gas flow rate increases and the flow velocity becomes faster, the above-described deviation of the gas flow velocity in the measurement flow path portion 3C increases. When a certain flow rate (for example, 6000 to 8000 L / h) is exceeded, a strong turbulent flow (vortex) is locally generated in the measurement flow path portion 3C, and a problem that the pressure loss suddenly increases occurs. . That is, in a region where a certain flow rate is higher than a certain flow rate, a correct flow rate cannot be measured unless the flow coefficient (instrument difference correction coefficient) is very large as shown in FIG. In addition, there is a problem in that the flow rate measurement value varies greatly and the flow rate error becomes large in the region where the flow rate exceeds a certain level.

そこで、図９（Ｂ）に示すように、ガス流入口２Ａ側、前面側、及び、背面側に端部が前記入口流路部３Ａの計測流路部３Ｃとの連結部の内壁と接するように水平に整流板７を設けるガスメータ１が提案されている（特許文献２）。このガスメータ１によれば、ガスが整流板７にぶつかることによって、ガスの偏った流れを乱し、かき混ぜ、均一にしてから計測流路部３Ｃ内に流入させて、精度の良い流速計測を行うことができる。しかしながら、図９(Ｂ)に示す従来のガスメータ１では、高流量域においては整流板７が全くない状態よりは、流量特性は改善されていたが完全に安定するまでは達成できていない、という問題があった。
特開平９−４３０１５号公報特開２００６−１１８８６４号公報 Therefore, as shown in FIG. 9B, the ends of the gas inlet 2A side, the front side, and the rear side are in contact with the inner wall of the connecting portion of the inlet channel portion 3A with the measurement channel portion 3C. A gas meter 1 in which a rectifying plate 7 is provided horizontally is proposed (Patent Document 2). According to the gas meter 1, when the gas collides with the rectifying plate 7, the uneven flow of the gas is disturbed, stirred, and made uniform, and then introduced into the measurement flow path section 3 C to perform accurate flow velocity measurement. be able to. However, in the conventional gas meter 1 shown in FIG. 9 (B), the flow rate characteristic is improved but not achieved until it is completely stabilized as compared with the state where there is no rectifying plate 7 in the high flow rate region. There was a problem.
Japanese Patent Laid-Open No. 9-43015 JP 2006-118864 A

そこで、本発明は、上記のような問題点に着目し、高流量域でも精度の良い流速計測を行うことができるガスメータを提供することを課題とする。 Therefore, the present invention focuses on the above-described problems, and an object thereof is to provide a gas meter that can perform accurate flow velocity measurement even in a high flow rate region.

上記課題を解決するためになされた請求項１記載の発明は、ガス流入口と連通すると共に鉛直方向に設けられた入口流路部と、前記入口流路部内に配置された前面から背面又は背面から前面に向かってガスが流れる開口が設けられた弁座部と、前記弁座部と当接して開口を塞いでガスの流れを遮断する遮断弁と、ガス流出口と連通すると共に鉛直方向に設けられた出口流路部と、流速センサが設けられた、前記入口流路部及び前記出口流路部間に水平方向に設けられた計測流路部と、前記入口流路部及び前記計測流路部の連結部の内壁と接するように水平に設けた整流板と、を備えたガスメータにおいて、前記整流板には、前記ガス流出口側の端部のうち最も前記弁座部の開口におけるガスの流れ方向下流側から前記ガス流出口側に向かって突起する第１の突起部が設けられていることを特徴とするガスメータに存する。 The invention according to claim 1, which has been made to solve the above-mentioned problems, includes an inlet channel portion that communicates with a gas inlet and is provided in a vertical direction, and a front surface to a rear surface or a rear surface disposed in the inlet channel portion. A valve seat provided with an opening through which gas flows from the front to the front, a shut-off valve that contacts the valve seat and closes the opening to block the gas flow, and communicates with the gas outlet and in the vertical direction An outlet channel provided; a measurement channel provided in a horizontal direction between the inlet channel and the outlet channel provided with a flow velocity sensor; the inlet channel and the measurement flow; A gas meter provided with a rectifying plate provided horizontally so as to be in contact with the inner wall of the connecting portion of the path portion, wherein the rectifying plate includes a gas at an opening of the valve seat portion most at an end portion on the gas outlet side. From the downstream side in the flow direction toward the gas outlet It consists in the gas meter, wherein the first protrusion to be raised are provided.

請求項２記載の発明は、前記入口流路部及び前記計測流路部の連結部が、前記弁座部の開口におけるガスの流れ方向上流側に向かって流路が広がるように設けられ、前記整流板には、前記ガス流出口側の端部のうち最も前記弁座部の開口におけるガスの流れ方向上流側から前記ガス流出口側に向かって突起する第２の突起部が設けられている
ことを特徴とする請求項１に記載のガスメータに存する。 The invention according to claim 2 is provided such that the connection portion of the inlet flow passage portion and the measurement flow passage portion is provided such that the flow passage extends toward the upstream side in the gas flow direction at the opening of the valve seat portion, The rectifying plate is provided with a second protruding portion that protrudes from the upstream side in the gas flow direction at the opening of the valve seat portion toward the gas outlet side among the ends on the gas outlet side. It exists in the gas meter of Claim 1 characterized by the above-mentioned.

請求項３記載の発明は、ガス流入口と連通すると共に鉛直方向に設けられた入口流路部と、ガス流出口と連通すると共に鉛直方向に設けられた出口流路部と、流速センサが設けられた、前記入口流路部及び前記出口流路部間に水平方向に設けられた、計測流路部と、前記入口流路部及び前記計測流路部の連結部内壁と接するように水平に設けた整流板と、を備えたガスメータにおいて、前記入口流路部及び前記計測流路部の連結部が、前面側又は背面側に向かって流路が広がるように設けられ、前記整流板には、前記ガス流出口側の端部のうち最も前記連結部において流路が広がる方向側から前記ガス流出口側に向かって突起する第２の突起部が設けられていることを特徴とするガスメータに存する。 According to a third aspect of the present invention, there is provided an inlet channel portion that communicates with the gas inlet and is provided in the vertical direction, an outlet channel portion that communicates with the gas outlet and is provided in the vertical direction, and a flow rate sensor. The measurement channel provided in the horizontal direction between the inlet channel and the outlet channel, and horizontally so as to contact the inner wall of the connection between the inlet channel and the measurement channel In the gas meter provided with the rectifying plate provided, the connection portion of the inlet flow channel portion and the measurement flow channel portion is provided so that the flow channel spreads toward the front side or the back side, The gas meter is provided with a second projecting portion that projects from the end of the gas outlet side toward the gas outlet side from the direction in which the flow path expands most at the connecting portion. Exist.

請求項４記載の発明は、前記入口流路部及び前記計測流路部の連結部において前記整流板と接する内壁に上流側が流路中心に向かって突起するような段差部が設けられ、前記整流板が、前記段差部上に搭載されて設けられていることを特徴とする請求項１〜３何れか１項に記載のガスメータに存する。 According to a fourth aspect of the present invention, a step portion is provided on the inner wall contacting the rectifying plate at the connecting portion of the inlet flow passage portion and the measurement flow passage portion so that the upstream side protrudes toward the flow passage center. 4. The gas meter according to claim 1, wherein a plate is mounted on the step portion.

請求項５記載の発明は、前記入口流路部及び前記計測流路部の連結部において前記整流板と接する内壁と、前記整流板と、の間の隙間にシール剤を塗布したことを特徴とする請求項１〜３何れか１項に記載のガスメータに存する。 The invention according to claim 5 is characterized in that a sealant is applied to a gap between the inner wall in contact with the rectifying plate and the rectifying plate in the connecting portion of the inlet flow channel portion and the measurement flow channel portion. It exists in the gas meter of any one of Claims 1-3 to do.

請求項６記載の発明は、前記入口流路部及び前記計測流路部の連結部において前記整流板と接する内壁に前記整流板の前記ガス流入口側、前記前面側、及び、前記背面側、の端部が嵌められる溝が形成された弾性部材が、設けられたことを特徴とする請求項１〜３何れか１項に記載のガスメータに存する。 The invention according to claim 6 is the gas inlet side, the front side, and the back side of the rectifying plate on the inner wall in contact with the rectifying plate in the connection portion of the inlet channel portion and the measurement channel portion, The gas meter according to any one of claims 1 to 3, wherein an elastic member having a groove into which the end of the gas fitting is formed is provided.

請求項７記載の発明は、前記入口流路部及び前記計測流路部の連結部の内壁にガスの流れ方向に沿うようにボスが突設され、前記整流板が、前記ボスにビス止めされて設けられていることを特徴とする請求項１〜６何れか１項に記載のガスメータに存する。 According to a seventh aspect of the present invention, a boss protrudes from the inner wall of the connecting portion of the inlet flow channel portion and the measurement flow channel portion along the gas flow direction, and the rectifying plate is screwed to the boss. It exists in the gas meter of any one of Claims 1-6 characterized by the above-mentioned.

請求項８記載の発明は、前記ボスの側面をＲ形状に設けたことを特徴とする請求項７記載のガスメータに存する。 The invention according to claim 8 resides in the gas meter according to claim 7, wherein the side surface of the boss is provided in an R shape.

請求項９記載の発明は、前記整流板の端面をＲ形状に設けたことを特徴とする請求項１〜８何れか１項に記載のガスメータに存する。 The invention according to claim 9 is the gas meter according to any one of claims 1 to 8, wherein an end face of the current plate is provided in an R shape.

以上説明したように請求項１記載の発明によれば、弁座部の開口に前面から背面に向かってガスが流れる場合、ガス流入口から入ってきたガスは、弁座部で一度ガスメータ背面に流れ、ガスメータの背面をたどって下降してくるため、背面で特に流速が早くなっている。そこで、整流板にガス流出口側の端部のうち最も弁座部の開口におけるガスの流れ方向下流側である背面側からガス流出口に向かって突起する第１の突起部を設けることにより、背面側の速い流れを第１の突起部に意図的にぶつけて、ガスメータ背面側に偏ったガスの流れを乱し、かき混ぜ、均一にし、それを計測流路部に偏りなく流入させることができる。また、弁座部の開口に背面から前面に向かってガスが流れる場合、ガス流入口から入ってきたガスは、弁座部で一度ガスメータ前面に流れ、ガスメータの前面をたどって下降してくるため、前面で特に流速が速くなっている。そこで、整流板にガス流出口側の端部のうち最も弁座部の開口におけるガスの流れ方向下流側である前面側からガス流出口に向かって突起する第１の突起部を設けることにより、前面側の速い流れを第１の突起部に意図的にぶつけて、ガスメータ前面側に偏ったガスの流れを乱し、かき混ぜ、均一にし、それを計測流路部に偏りなく流入させることができる。これにより、計測流路部内でも偏りのない均一な流れとなり、高流量域でも偏りのない均一な流れとなり、計測流路部内で乱流(渦)が発生することを抑制できるため、高流量域でも流量計測値のばらつきが小さく、流量計測誤差を小さくして、流速計測精度の向上を図ることができる。 As described above, according to the first aspect of the present invention, when gas flows from the front surface to the back surface through the opening of the valve seat portion, the gas that has entered from the gas inlet once enters the back surface of the gas meter at the valve seat portion. Since it flows and descends following the back of the gas meter, the flow velocity is particularly fast on the back. Therefore, by providing a first protrusion that protrudes toward the gas outlet from the back side, which is the downstream side of the gas flow direction in the opening of the valve seat, among the ends on the gas outlet side of the rectifying plate, By deliberately hitting the fast flow on the back side against the first protrusion, the gas flow biased to the back side of the gas meter can be disturbed, stirred, and made uniform, and it can flow evenly into the measurement channel . In addition, when gas flows from the back to the front through the opening of the valve seat, the gas that has entered from the gas inlet once flows to the front of the gas meter at the valve seat and descends along the front of the gas meter. The flow velocity is particularly fast at the front. Therefore, by providing a first protrusion that protrudes toward the gas outlet from the front side that is the most downstream side of the gas flow direction in the opening of the valve seat portion among the ends on the gas outlet side of the rectifying plate, By deliberately hitting the fast flow on the front side against the first protrusion, the gas flow biased to the front side of the gas meter can be disturbed, stirred and made uniform, and it can flow evenly into the measurement channel . As a result, the flow is uniform even in the measurement flow path, and the flow is uniform even in the high flow area, and the occurrence of turbulence (vortices) in the measurement flow path can be suppressed. However, variations in flow rate measurement values are small, and flow rate measurement errors can be reduced to improve flow velocity measurement accuracy.

請求項２記載の発明によれば、流路が広がる方向側、つまり、第２の突起部へ流れこんだ流れを第２の突起部ではね返し、流路中央部へ流すことで、流路中央部を流れていた速い流れとぶつかり、かき混ざり、流れが均一になり、それを計測流路部に偏りなく流入させることができる。これにより、計測流路部内でも偏りのない均一な流れとなり、高流量域でも偏りのない均一な流れとなり、計測流路部内で乱流(渦)が発生することを抑制できるため、高流量域でも流量計測値のばらつきが小さく、流量計測誤差を小さくして、流速計測精度の向上を図ることができる。 According to the second aspect of the present invention, the flow direction that spreads the flow path, that is, the flow that has flowed into the second protrusion is rebounded by the second protrusion and is allowed to flow to the center of the flow path. It collides with the fast flow that has been flowing through the section, mixes, the flow becomes uniform, and it can flow into the measurement flow path section evenly. As a result, the flow is uniform even in the measurement flow path, and the flow is uniform even in the high flow area, and the occurrence of turbulence (vortices) in the measurement flow path can be suppressed. However, variations in flow rate measurement values are small, and flow rate measurement errors can be reduced to improve flow velocity measurement accuracy.

請求項４記載の発明によれば、整流板と入口流路部及び出口流路部の連結部内壁との隙間をなくすことができる。これにより、隙間を通過した速い流れが計測流路部内に入り込んでしまい、計測流路部内が偏った流れとなり、流量特性に悪影響を与えることがなくなり、より一層、流速計測精度の向上を図ることができる。また、整流板をビス止めする場合、整流板を段差部の上に載せてからビス止めできるため、組み立てが安定し、作業性が向上し、組み立て工数を削減することができる。 According to invention of Claim 4, the clearance gap between a baffle plate and the connection part inner wall of an inlet flow path part and an outlet flow path part can be eliminated. As a result, the fast flow that has passed through the gap enters the measurement flow path section, and the measurement flow path section becomes a biased flow, which does not adversely affect the flow rate characteristics and further improve the flow velocity measurement accuracy. Can do. Moreover, when screwing the current plate, the screw can be secured after the current plate is placed on the stepped portion, so that the assembly is stable, workability is improved, and the number of assembly steps can be reduced.

請求項５及び６記載の発明によれば、整流板と入口流路部及び計測流路部の連結部内壁との隙間をなくすことができる。これにより、隙間を通過した速い流れが計測流路部内に入り込んでしまい、計測流路部内が偏った流れとなり、流量特性に悪影響を与えることがなくなり、より一層、流速計測精度の向上を図ることができる。 According to invention of Claim 5 and 6, the clearance gap between a baffle plate and the connection part inner wall of an inlet flow path part and a measurement flow path part can be eliminated. As a result, the fast flow that has passed through the gap enters the measurement flow path section, and the measurement flow path section becomes a biased flow, which does not adversely affect the flow rate characteristics and further improve the flow velocity measurement accuracy. Can do.

請求項７記載の発明によれば、整流板にぶつかって反射したガスがボスにまでぶつかって、乱反射し、いろいろな方向に流れ、ぶつかり合い、全体の流れを均一にミックスすることに寄与し、より一層、流量特性を改善して、流速計測精度の向上を図ることができる。また、整流板を接着剤で固定するよりも作業性がよく、作業工数が削減される。また、高流量域で整流板が吹き飛んでしまうという心配がなく、品質が安定する。 According to the invention of claim 7, the gas reflected from the baffle plate hits the boss, diffusely reflects, flows in various directions, collides, and contributes to uniformly mixing the entire flow, The flow rate characteristics can be further improved, and the flow rate measurement accuracy can be improved. Moreover, workability is better than fixing the current plate with an adhesive, and the number of work steps is reduced. Moreover, there is no worry that the rectifying plate blows off in a high flow rate region, and the quality is stabilized.

請求項８記載の発明によれば、ボスがＲ形状であるため、ガスがボスとぶつかってより一層いろいろな方向に反射して流れ、ぶつかり合い、全体の流れを均一にミックスする。これにより、より一層、流量特性を改善して、流量計測精度の向上を図ることができる。 According to the eighth aspect of the present invention, since the boss has an R shape, the gas collides with the boss and flows in various directions, collides, and mixes the entire flow uniformly. Thereby, the flow rate characteristics can be further improved and the flow rate measurement accuracy can be improved.

請求項９記載の発明によれば、整流板の端面にぶつかったガスを滑らかに下流側に送り込むことができる。この結果、流量特性と圧力損失との両方を測定した結果、両方とも改善することができる。 According to the ninth aspect of the present invention, the gas hitting the end face of the current plate can be smoothly fed downstream. As a result, as a result of measuring both the flow characteristics and the pressure loss, both can be improved.

以下、本発明のガスメータの実施形態を図面に基づいて説明する。図１に示すガスメータ１は、略箱型の外形を有し、マイクロコンピュータ(マイコン)を利用して流量計算処理や保安制御を行う電子式のガスメータである。ガスメータ１は、ガス供給源に接続されるガス流入口２Ａとガス消費源に接続されるガス流出口２Ｂとの間に連通する流路３を有している。ガス流入口２Ａ及びガス流出口２Ｂは、円筒状であり、側面にネジ山が形成され、やや上方に突出している。流路３は、アルミ製の入口流路部３Ａと、出口流路部３Ｂと、計測流路部３Ｃと、から構成され、Ｕ字状に設けられている。 Hereinafter, embodiments of a gas meter of the present invention will be described with reference to the drawings. A gas meter 1 shown in FIG. 1 is an electronic gas meter that has a substantially box-shaped outer shape and performs flow rate calculation processing and security control using a microcomputer. The gas meter 1 has a flow path 3 that communicates between a gas inlet 2A connected to a gas supply source and a gas outlet 2B connected to a gas consumption source. The gas inflow port 2A and the gas outflow port 2B are cylindrical, have threads formed on the side surfaces, and protrude slightly upward. The flow path 3 includes an aluminum inlet flow path section 3A, an outlet flow path section 3B, and a measurement flow path section 3C, and is provided in a U shape.

入口流路部３Ａは、ガス流入口２Ａと連通すると共に鉛直方向に沿うように設けられている。この入口流路部３Ａは、弁座部４と、遮断弁５（図２）と、が設けられている。弁座部４は、図２に示すように、背壁部６Ａ及び前壁部６Ｂ間に設けられた壁部であり、その中央に円形の開口（図１）が設けられている。背壁部６Ａは、入口流路部３Ａの背面から突出した壁部であり、前壁部６Ｂよりも上流側に設けられている。前壁部６Ｂは、入口流路部３Ａの前面から突出した壁部であり、背壁部６Ａよりも下流側に設けられている。これにより、弁座部４の開口には、図２中の矢印に示すように、前面から背面に向かってガスが流れる。上記遮断弁５は、その弁体５Ａを前面から背面に向かって突出させて弁座部４の開口縁を塞ぐことにより、入口流路部３Ａの途中でガスの流れを遮断するように設けられている。 The inlet channel portion 3A communicates with the gas inlet 2A and is provided along the vertical direction. The inlet channel 3A is provided with a valve seat 4 and a shut-off valve 5 (FIG. 2). As shown in FIG. 2, the valve seat part 4 is a wall part provided between the back wall part 6A and the front wall part 6B, and a circular opening (FIG. 1) is provided at the center thereof. The back wall portion 6A is a wall portion protruding from the back surface of the inlet flow passage portion 3A, and is provided on the upstream side of the front wall portion 6B. The front wall portion 6B is a wall portion that protrudes from the front surface of the inlet channel portion 3A, and is provided on the downstream side of the back wall portion 6A. Thereby, gas flows into the opening of the valve seat portion 4 from the front surface to the back surface as shown by the arrows in FIG. The shut-off valve 5 is provided so as to shut off the gas flow in the middle of the inlet flow passage portion 3A by projecting the valve body 5A from the front surface toward the back surface and closing the opening edge of the valve seat portion 4. ing.

上述した入口流路部３Ａは、図２に示すように、計測流路部３Ｃとの連結部の流路を前面側（＝弁座部４の開口におけるガスの流れ方向上流側）に向かって広げる上壁部３Ａ１が設けられている。そして、この上壁部３Ａ１よりも下流側の入口流路部３Ａに樹脂製の整流板７が設けられている。この整流板７は、図３及び図４に示すように、ガス流入口２Ａ側、前面側、及び、背面側の端部がそれぞれ入口流路部３Ａの内壁に接するように設けられ、ガス流出口２Ｂ側の端部が開放されて設けられている。また、整流板７には、第１の突起部７Ａと、第２の突起部７Ｂと、ビス穴７Ｃ（図７参照）と、が設けられている。第１の突起部７Ａは、図３及び図４に示すように、整流板７のガス流出口２Ｂ側の端部のうち最も背面側（＝弁座部４の開口におけるガスの流れ方向下流側）からガス流出口２Ｂ側に向かって突起するように設けられている。第２の突起部７Ｂは、ガス流出口２Ｂ側の端部のうち最も前面側（＝弁座部４の開口におけるガスの流れ方向上流側、入口流路部３Ａ及び計測流路部３Ｃとの連結部において流路が広がる方向）からガス流出口２Ｂ側に向かって突出するように設けられている。ビス穴７Ｃは、図７に示すように、整流板７の板厚方向に貫通するように２つ又は３つ設けられている。 As shown in FIG. 2, the inlet flow path portion 3 A described above is directed to the front surface side (= upstream side of the gas flow direction at the opening of the valve seat portion 4) at the connection portion with the measurement flow path portion 3 C. An upper wall portion 3A1 to be expanded is provided. And the resin-made rectification | straightening board 7 is provided in 3 A of inlet flow-path parts downstream from this upper wall part 3 A1. As shown in FIGS. 3 and 4, the rectifying plate 7 is provided such that the gas inlet 2A side, the front side, and the rear side end are in contact with the inner wall of the inlet channel 3A. The end on the outlet 2B side is provided open. Further, the rectifying plate 7 is provided with a first projection 7A, a second projection 7B, and a screw hole 7C (see FIG. 7). As shown in FIGS. 3 and 4, the first protrusion 7 A is the rearmost side (= the downstream side in the gas flow direction at the opening of the valve seat portion 4) among the end portions on the gas outlet 2 B side of the rectifying plate 7. ) To the gas outlet 2B side. The second protrusion 7B is located at the frontmost side of the end on the gas outlet 2B side (= the upstream side in the gas flow direction at the opening of the valve seat part 4, the inlet channel 3A and the measurement channel 3C. It is provided so as to protrude toward the gas outlet 2B side from the direction in which the flow path expands at the connecting portion. As shown in FIG. 7, two or three screw holes 7 C are provided so as to penetrate in the plate thickness direction of the rectifying plate 7.

また、図５及び図６に示すように、上記上壁部３Ａ１からは、ボス８がガス流れ方向に沿って突出して設けられている。ボス８には、ビス穴８Ａ（図５参照）が設けられている。整流板７は、ビスＢ（図３及び図４）によってこのボス８に固定される。また、整流板７の端部が接する入口流路部３Ａの内壁には、図５及び図６に示すように、上流側が流路中心に向かって突起するような段差部３Ａ２が設けられている。この段差部３Ａ２と上記ボス８とを一体に設けるために、上記ボス８は入口流路部３Ａ内壁に沿って突出して設けられている。本実施形態では、ボス８は、入口流路部３Ａの前面側の内壁に沿って２つ立設されていて、入口流路部３Ａのガス流入口２Ａ側の内壁に沿って１つ立設されている。なお、この入口流路部３Ａのガス流入口２Ａ側の内壁に沿って立設されたボス８は、図５及び図６に示すように、上壁部３Ａ１の背面側の端部から距離Ｌだけ離間して配置されている。 Further, as shown in FIGS. 5 and 6, a boss 8 is provided so as to protrude from the upper wall portion 3A1 along the gas flow direction. The boss 8 is provided with a screw hole 8A (see FIG. 5). The current plate 7 is fixed to the boss 8 by screws B (FIGS. 3 and 4). Further, as shown in FIGS. 5 and 6, a step portion 3 A 2 is provided on the inner wall of the inlet flow passage portion 3 A with which the end of the rectifying plate 7 is in contact, so that the upstream side protrudes toward the flow passage center. . In order to provide the step portion 3A2 and the boss 8 integrally, the boss 8 protrudes along the inner wall of the inlet flow passage portion 3A. In the present embodiment, two bosses 8 are erected along the inner wall on the front surface side of the inlet channel portion 3A, and one boss 8 is erected along the inner wall on the gas inlet 2A side of the inlet channel portion 3A. Has been. The boss 8 erected along the inner wall of the inlet channel 3A on the gas inlet 2A side is a distance L from the end on the back side of the upper wall 3A1, as shown in FIGS. Are spaced apart.

また、ボス８と段差部３Ａ２とは同一の高さで設けられている。整流板７は、この段差部３Ａ２及びボス８に搭載された状態でボス８にビス止めされている。また、図５に示すように、上記ボス８の側面、ボス８と段差部３Ａ２との連結面は、Ｒ形状に設けられている。さらに、上記整流板７の入口流路部３Ａの内壁と接していない端面は、図７に示すようにＲ形状に設けられている。 The boss 8 and the stepped portion 3A2 are provided at the same height. The current plate 7 is screwed to the boss 8 while being mounted on the stepped portion 3A2 and the boss 8. Moreover, as shown in FIG. 5, the side surface of the boss 8 and the connecting surface between the boss 8 and the stepped portion 3A2 are provided in an R shape. Further, the end face of the rectifying plate 7 not in contact with the inner wall of the inlet flow passage portion 3A is provided in an R shape as shown in FIG.

出口流路部３Ｂは、図１に示すように、ガス流出口２Ｂと連通すると共に鉛直方向に沿うように設けられている。計測流路部３Ｃは、入口流路部３Ａ及び出口流路部３Ｂ間に水平方向に沿うように設けられている。上記計測流路部３Ｃには、流速センサとしての一対の超音波センサ（図示せず）が設けられている。また、計測流路部３Ｃは、一対の超音波センサ間を流れるガスを整流する複数の整流板９を含む整流器１０が配置されている。整流器１０は、図１に示すように、それぞれが平行になるようにして配置された複数の整流板９及びこれを支持する筒状の外枠部１１から基本構成されている。また、外枠部１１は、上述した整流板７と距離Ａだけ重なるように設けられている。 As shown in FIG. 1, the outlet channel portion 3 B communicates with the gas outlet 2 B and is provided along the vertical direction. The measurement flow path portion 3C is provided along the horizontal direction between the inlet flow path portion 3A and the outlet flow path portion 3B. The measurement flow path section 3C is provided with a pair of ultrasonic sensors (not shown) as flow velocity sensors. In addition, the rectifier 10 including a plurality of rectifying plates 9 that rectifies the gas flowing between the pair of ultrasonic sensors is disposed in the measurement flow path portion 3C. As shown in FIG. 1, the rectifier 10 is basically composed of a plurality of rectifying plates 9 arranged in parallel with each other and a cylindrical outer frame portion 11 that supports the rectifying plates 9. Further, the outer frame portion 11 is provided so as to overlap the rectifying plate 7 described above by a distance A.

上述した構成のガスメータ１のガスの流れについて説明する。ガス流入口２Ａから流入したガスは、入口流路部３Ａに沿って鉛直下向きに進む。その後、弁座部４の開口部を通ると、図２の矢印に示すように、ガスメータ１の背面側に向かって流れガスメータ１の背面をたどって鉛直下向きに下降する。その後、ガスは、距離Ａだけ重なるように鉛直方向に離間して配置された整流板７と外枠部１１とによって、図１の矢印に示すように、一旦ガス流入口２Ａ側に曲がった後にガス流出口２Ｂに曲がって迂回した後に整流器１０に流入される。 The gas flow of the gas meter 1 having the above-described configuration will be described. The gas flowing in from the gas inlet 2A proceeds vertically downward along the inlet flow path portion 3A. Thereafter, when passing through the opening of the valve seat portion 4, as shown by the arrow in FIG. 2, it flows toward the back side of the gas meter 1, follows the back surface of the gas meter 1, and descends vertically downward. After that, after the gas is once bent to the gas inlet 2A side by the rectifying plate 7 and the outer frame portion 11 which are arranged apart from each other in the vertical direction so as to overlap by the distance A, as shown by the arrow in FIG. After being bent around the gas outlet 2B, the gas flows into the rectifier 10.

整流器１０に流入したガスは、整流板９にて整流され、この整流板９の近傍に配置された、ガスの流量を検出するための一対の超音波センサにて流量が計測される。即ち、この流量計測では、上述したように、上流方向への超音波の伝搬時間Ｔ１及び下流方向への超音波の伝搬時間Ｔ２に基づいて流速Ｖ＝Ｌ／２ｃｏｓ（１／Ｔ１−１／Ｔ２）を求めることができるので、流量＝ＫＶＳとして求めることができる。この流量計測は、図示しないマイコンにて処理される。整流器１０から流出したガスは、図１中の細矢印で示すように、出口流路部３Ｂに沿って鉛直上向きに流れガス流出口２Ｂから流出していく。 The gas flowing into the rectifier 10 is rectified by the rectifying plate 9 and the flow rate is measured by a pair of ultrasonic sensors arranged in the vicinity of the rectifying plate 9 for detecting the gas flow rate. That is, in this flow rate measurement, as described above, the flow velocity V = L / 2 cos (1 / T1-1 / T2) based on the ultrasonic wave propagation time T1 in the upstream direction and the ultrasonic wave propagation time T2 in the downstream direction. ) Can be obtained, and can be obtained as flow rate = KVS. This flow rate measurement is processed by a microcomputer (not shown). The gas flowing out of the rectifier 10 flows vertically upward along the outlet flow path portion 3B and flows out of the gas outlet 2B, as indicated by the thin arrows in FIG.

上述したガスメータ１によれば、整流板７には、ガス流出口２Ｂ側の端部のうち最も背面側からガス流出口２Ｂに向かって突起する第１の突起部７Ａが設けられている。上述したようにガス流入口２Ａから入ってきたガスは、弁座部４で一度ガスメータ１背面に流れ、ガスメータ１の背面をたどって下降してくるため、背面側で特に流速が早くなっている。そこで、整流板７にガス流出口２Ｂ側の端部のうち最も背面側からガス流出口２Ｂに向かって突起する第１の突起部７Ａを設けることにより、背面側の速い流れを第１の突起部７Ａに意図的にぶつけて、ガスメータ１背面側に偏ったガスの流れを乱し、かき混ぜ、均一にし、それを計測流路部３Ｃの整流器１０に偏りなく流入させることができる。これにより、計測流路部３Ｃの整流器１０内でも偏りのない均一な流れとなり、高流量域でも偏りのない均一な流れとなり、計測流路部３Ｃの整流器１０内で乱流(渦)が発生することを抑制できるため、高流量域でも流量計測値のばらつきが小さく、流量計測誤差を小さくして、流速計測精度の向上を図ることができる。 According to the gas meter 1 described above, the rectifying plate 7 is provided with the first protruding portion 7A that protrudes from the back side toward the gas outlet 2B among the end portions on the gas outlet 2B side. As described above, the gas that has entered from the gas inlet 2A once flows to the back surface of the gas meter 1 at the valve seat portion 4 and descends along the back surface of the gas meter 1, so that the flow velocity is particularly fast on the back surface side. . Therefore, by providing the rectifying plate 7 with the first protrusion 7A that protrudes from the rearmost side toward the gas outlet 2B among the end portions on the gas outlet 2B side, the first protrusion can cause the fast flow on the rear side. By intentionally hitting the part 7A, the gas flow biased toward the back side of the gas meter 1 is disturbed, stirred, and made uniform, and it can be made to flow evenly into the rectifier 10 of the measurement flow path part 3C. As a result, the flow is uniform in the rectifier 10 of the measurement flow path section 3C, and the flow is uniform even in the high flow rate range, and turbulence (vortex) is generated in the rectifier 10 of the measurement flow path section 3C. Therefore, even in a high flow rate range, the variation in the flow rate measurement value is small, the flow rate measurement error can be reduced, and the flow velocity measurement accuracy can be improved.

また、上述したガスメータ１によれば、整流板７には、ガス流出口２Ｂ側の端部のうち最も前面側からガス流出口２Ｂに向かって突起する第２の突起部７Ｂが設けられている。第２の突起部７Ｂは、流路３が広げる上壁部３Ａ１の前面側（奥）の部分であり、流速は遅いため、ここに第２の突起部７Ｂを設けても効果のないように思われた。しかしながら、流路が広がった前面側、つまり、第２の突起部７Ｂへ流れこんだ遅い流れを第２の突起部７Ｂではね返し、流路中央部へ流すことで、流路中央部を流れていた速い流れと遅い流れとがぶつかり、かき混ざり、流れが均一になり、それを計測流路部３Ｃ内の整流器１０に偏りなく流入させることができる。これにより、計測流路部３Ｃの整流器１０内でも偏りのない均一な流れとなり、高流量域でも偏りのない均一な流れとなり、計測流路部３Ｃ内で乱流(渦)が発生することを抑制できるため、高流量域でも流量計測値のばらつきが小さく、流量計測誤差を小さくして、流速計測精度の向上を図ることができる。 Further, according to the gas meter 1 described above, the rectifying plate 7 is provided with the second projecting portion 7B that projects from the front side toward the gas outlet 2B among the end portions on the gas outlet 2B side. . The second protrusion 7B is a part on the front side (back) of the upper wall 3A1 that the flow path 3 widens, and the flow velocity is slow. Therefore, even if the second protrusion 7B is provided here, there is no effect. It seemed. However, the slow flow that has flowed into the front surface side where the flow path has spread, that is, the second protrusion 7B is rebounded by the second protrusion 7B and flows to the center of the flow path. The fast flow and the slow flow collide with each other, and the flow becomes uniform, and the flow becomes uniform, and it can be uniformly introduced into the rectifier 10 in the measurement flow path section 3C. As a result, the flow is uniform in the rectifier 10 of the measurement flow path section 3C, and the flow is uniform even in the high flow rate range, and turbulence (vortex) is generated in the measurement flow path section 3C. Since it can be suppressed, the variation in the flow rate measurement value is small even in the high flow rate range, the flow rate measurement error can be reduced, and the flow velocity measurement accuracy can be improved.

また、上述したガスメータ１は、アルミ製の入口流路部３Ａに樹脂製の整流板７をビスＢで固定するため、どうしても入口流路部３Ａの内壁と整流板７の端部との間に隙間Ｓ（図４参照）が生じてしまう。隙間Ｓは、入口流路部３Ａと整流板７との接触面すべてに生じるが、最悪条件においては最大０．５ｍｍ程度の隙間Ｓが生じる場合がある。ここで、最悪条件とは、バラつく要因（入口流路部３Ａの寸法、整流板７の寸法、ボス８のビス穴８Ａの寸法、整流板７のビス穴７Ｃの寸法、組み付け時の寸法等）全てが、隙間Ｓを大きくする方向に重なったときのことである。特に、第１の突起部７Ａの隙間は、悪影響が大きい。 Moreover, since the gas meter 1 mentioned above fixes the resin rectifying plate 7 to the aluminum inlet flow passage portion 3A with the screw B, the gap between the inner wall of the inlet flow passage portion 3A and the end portion of the rectifying plate 7 is inevitably increased. A gap S (see FIG. 4) is generated. The gap S occurs on all the contact surfaces between the inlet flow path portion 3A and the rectifying plate 7, but a gap S of about 0.5 mm at maximum may occur in the worst condition. Here, the worst conditions are factors that vary (dimensions of the inlet flow passage portion 3A, dimensions of the rectifying plate 7, dimensions of the screw holes 8A of the boss 8, dimensions of the screw holes 7C of the rectifying plate 7, dimensions at the time of assembly, etc. ) When all overlap in the direction of increasing the gap S. In particular, the gap between the first protrusions 7A has a large adverse effect.

そこで、上述したガスメータ１によれば、整流板７と接する入口流路部３Ａの内壁に上流側が流路中心に向かって突起するような段差部３Ａ２が設けられ、整流板７が段差部３Ａ２上に搭載されている。このように段差部３Ａ２を設けることにより、図６に示すように、整流板７と入口流路部３Ａの内壁との間に隙間Ｓが生じても段差部３Ａ２により塞いで隙間Ｓをなくすことができる。これにより、隙間Ｓを通過した速い流れが計測流路部３Ｃの整流器１０内に入り込んでしまい、計測流路部３Ｃの整流器１０内が偏った流れとなり、流量特性に悪影響を与えることがなくなり、より一層、流速計測精度の向上を図ることができる。また、組み立て時、整流板７をこの段差部３Ａ２の上に載せてからビス止めできるため、組み立てが安定し、作業性が向上し、組み立て工数を削減することもできる。 Therefore, according to the gas meter 1 described above, the step portion 3A2 is provided on the inner wall of the inlet flow passage portion 3A in contact with the rectifying plate 7 so that the upstream side protrudes toward the flow passage center, and the rectifying plate 7 is located on the step portion 3A2. It is mounted on. By providing the step portion 3A2 in this way, as shown in FIG. 6, even if a gap S is generated between the rectifying plate 7 and the inner wall of the inlet flow passage portion 3A, the step portion 3A2 closes and eliminates the gap S. Can do. As a result, the fast flow that has passed through the gap S enters the rectifier 10 of the measurement flow path portion 3C, and the flow inside the rectifier 10 of the measurement flow path portion 3C becomes a biased flow, so that the flow characteristics are not adversely affected. Further improvement in flow rate measurement accuracy can be achieved. Moreover, since the baffle plate 7 can be screwed after being placed on the stepped portion 3A2 during assembly, the assembly is stable, workability is improved, and the number of assembly steps can be reduced.

また、上述したガスメータ１によれば、入口流路部３Ａに設けたボス８上に整流板７を搭載してビスＢにより整流板７をボス８に固定して設けた。これによれば、整流板７にぶつかって反射したガスがボス８にまでぶつかって、乱反射し、いろいろな方向に流れ、ぶつかり合い、全体の流れを均一にミックスすることに寄与し、より一層、流量特性を改善して、流速計測精度の向上を図ることができる。また、整流板７を接着剤により固定するよりも作業性がよく、作業工数が削減される。また、高流量域で整流板７が吹き飛んでしまうという心配がなく、品質が安定する。 Further, according to the gas meter 1 described above, the rectifying plate 7 is mounted on the boss 8 provided in the inlet channel portion 3A, and the rectifying plate 7 is fixed to the boss 8 with the screw B. According to this, the gas reflected on the rectifying plate 7 hits the boss 8 and is diffusely reflected, flowing in various directions, colliding, contributing to the uniform mixing of the entire flow, and more, It is possible to improve flow rate characteristics and improve flow velocity measurement accuracy. Moreover, workability is better than fixing the current plate 7 with an adhesive, and the number of work steps is reduced. Moreover, there is no worry that the rectifying plate 7 is blown off in a high flow rate region, and the quality is stabilized.

さらに、本発明者らは、ボス８の設ける位置を検討した結果、上壁部３Ａ１の背面側端部では高流量域において流量特性が改善されないことが分かった。これは、ボス８を上壁部３Ａ１の背面側端部に設けると上壁部３Ａ１に達したガスが、ボス８を伝わって流れた後に整流板７とぶつかるため、ガスの逃げ場がなく、全体の流れを均等にミックスすることに寄与度がたりなくなるからである。そこで、上述したようにボス８を上壁部３Ａ１の背面側の端部から距離Ｌ（例えば５ｍｍ程度）だけ離間して配置した(図５及び図６参照)。これにより、上壁部３Ａ１に達したガスが、整流板７とぶつかった後にボス８とぶつかって、いろんな方向に反射して流れ、ぶつかりあい、全体の流れを均等にミックスするため、流量特性をより一層改善することができた。 Furthermore, as a result of studying the position where the boss 8 is provided, the present inventors have found that the flow rate characteristics are not improved in the high flow rate region at the rear side end of the upper wall 3A1. This is because when the boss 8 is provided at the rear side end of the upper wall portion 3A1, the gas reaching the upper wall portion 3A1 collides with the rectifying plate 7 after flowing through the boss 8, so there is no escape space for the gas. This is because there is no contribution to evenly mixing the flows. Therefore, as described above, the boss 8 is arranged at a distance L (for example, about 5 mm) away from the rear end of the upper wall 3A1 (see FIGS. 5 and 6). As a result, the gas that has reached the upper wall portion 3A1 collides with the rectifying plate 7 and then collides with the boss 8, flows in various directions, collides, and mixes the entire flow evenly. It was possible to improve further.

また、上述したガスメータ１によれば、ボス８の側面と、ボス８及び段差部３Ａ２の連結面とが、Ｒ形状であるため、ガスが、ボス８の側面とボス８及び段差部３Ａ２の連結面とにぶつかってより一層いろいろな方向に反射して流れ、ぶつかり合い、全体の流れを均一にミックスする。これにより、より一層、流量特性を改善して、流量計測精度の向上を図ることができる。 Moreover, according to the gas meter 1 mentioned above, since the side surface of the boss 8 and the connecting surface of the boss 8 and the stepped portion 3A2 are R-shaped, the gas is connected to the side surface of the boss 8 and the boss 8 and the stepped portion 3A2. It collides with the surface and reflects in various directions, collides, and mixes the entire flow uniformly. Thereby, the flow rate characteristics can be further improved and the flow rate measurement accuracy can be improved.

また、上記整流板７を備えると、高流量域の流量特性は改善されるが、整流板７の面積を大きくすると、今度は圧力損失が大きくなり、ガスメータ１として問題が生じてくる。ガスメータ１内部の圧力損失が大きくなると、下流側のガス機器に供給するガス圧が低くなり、燃焼不良などの問題が生じてしまう可能性がある。よって、整流板７の面積は、流路３の面積、流量に応じて最適値に設計しなければならない。高流領域の流量特性と圧力損失とは、まさに相反した要因である。そこで、上述したようにガスメータ１の入口流路部３Ａの内壁と接していない部分の整流板７の端面をＲ形状に設けることにより（図７参照）、整流板７の端面にぶつかったガス流をなめらかに下流側に送り込む効果を得ることができた。この結果、流量特性と圧力損失との両方を測定した結果、両方とも改善することができた。特に、高流量域において、整流板７には予想以上の速いガス流がぶつかる。整流板７の端面をＲ形状とするという簡単な構成で圧力損失を小さく改善する効果を得ることができた。 In addition, when the rectifying plate 7 is provided, the flow characteristics in the high flow rate region are improved. However, when the area of the rectifying plate 7 is increased, the pressure loss is increased and the gas meter 1 has a problem. When the pressure loss inside the gas meter 1 increases, the gas pressure supplied to the downstream gas equipment decreases, and problems such as poor combustion may occur. Therefore, the area of the rectifying plate 7 must be designed to an optimum value according to the area and flow rate of the flow path 3. The flow characteristics and pressure loss in the high flow region are just contradictory factors. Therefore, as described above, the end face of the rectifying plate 7 that is not in contact with the inner wall of the inlet flow passage portion 3A of the gas meter 1 is provided in an R shape (see FIG. 7), so that the gas flow hit the end face of the rectifying plate 7 It was possible to obtain the effect of smoothly feeding the water downstream. As a result, as a result of measuring both flow characteristics and pressure loss, both were improved. In particular, in the high flow rate region, the rectifying plate 7 hits a gas flow that is faster than expected. An effect of reducing pressure loss with a simple configuration in which the end face of the rectifying plate 7 has an R shape can be obtained.

なお、上述した実施形態では、段差部３Ａ２を設けて入口流路部３Ａと整流板７との隙間Ｓを塞いでいたが、本発明はこれに限ったものではない。例えば、段差部３Ａ２を設けていなくても上記隙間Ｓにシール剤を塗布して隙間Ｓを塞ぐことも考えられる。 In the above-described embodiment, the step portion 3A2 is provided to close the gap S between the inlet flow passage portion 3A and the rectifying plate 7, but the present invention is not limited to this. For example, it is also conceivable to seal the gap S by applying a sealant to the gap S without providing the stepped portion 3A2.

また、図８に示すように、整流板７と接する内壁に整流板７のガス流入口２Ａ、前面側、及び、背面側、の端部が嵌められる溝１２Ａが形成された弾性部材としてのゴムブッシュ１２を設けて隙間Ｓを塞ぐようにしてもよい。 Further, as shown in FIG. 8, rubber as an elastic member in which grooves 12 A into which end portions of the gas inlet 2 A of the rectifying plate 7, the front side, and the back side are fitted are formed on the inner wall in contact with the rectifying plate 7. A bush 12 may be provided to close the gap S.

また、上述した実施形態では、整流板７に第１の突起部７Ａと第２の突起部７Ｂとの両方が設けられていたが、本発明はこれに限ったものではない。例えば、第１の突起部７Ａ及び第２の突起部７Ｂのうち何れか一方のみを設けるようにしてもよい。このようしても、整流板７に第１の突起部７Ａ及び第２の突起部７Ｂの両方を設けない場合に比べて、流量特性を改善することができる。 In the above-described embodiment, both the first protrusion 7A and the second protrusion 7B are provided on the current plate 7, but the present invention is not limited to this. For example, only one of the first protrusion 7A and the second protrusion 7B may be provided. Even if it does in this way, compared with the case where both the 1st projection part 7A and the 2nd projection part 7B are not provided in the baffle plate 7, a flow characteristic can be improved.

また、上述した実施形態では、弁座部４の開口に前面から背面に向かってガスが流れるように遮断弁５を正面から取り付けたガスメータ１に本発明を適用していたが、本発明はこれに限ったものではない。例えば、実施形態とは逆に、弁座部４の開口に背面から前面に向かってガスが流れるように、遮断弁５を背面から取り付けるように設けられたガスメータ１に本発明を適用してもよい。この場合、第１の突起部７Ａは、整流板７のガス流出口２Ｂ側の端部のうち最も前面側からガス流出口２Ｂ側に向かって突出するように設ければよい。また、このとき、入口流路部３Ａ及び計測流路部３Ｃの連結部の流路が背面側に向かって広がるようにガスメータ１が構成されていれば、第２の突起部７Ｂは、整流板７のガス流出口２Ｂ側の端部のうち最も背面側からガス流出口２Ｂ側に向かって突出するように設ければよい。 In the above-described embodiment, the present invention is applied to the gas meter 1 in which the shutoff valve 5 is attached from the front so that the gas flows from the front to the back of the opening of the valve seat portion 4. It is not limited to. For example, contrary to the embodiment, even if the present invention is applied to the gas meter 1 provided so that the shutoff valve 5 is attached from the back so that the gas flows from the back to the front through the opening of the valve seat portion 4. Good. In this case, the first protrusion 7A may be provided so as to protrude from the front side toward the gas outlet 2B side of the end of the rectifying plate 7 on the gas outlet 2B side. At this time, if the gas meter 1 is configured such that the flow path of the connection portion between the inlet flow path portion 3A and the measurement flow path portion 3C is widened toward the back side, the second protrusion 7B 7 may be provided so as to protrude from the rearmost side toward the gas outlet 2B side among the end portions on the gas outlet 2B side.

また、上述した実施形態では、入口流路部３Ａに整流板７を設けていたが、本発明はこれに限ったものではない。例えば、計測流路部３Ｃの入口流路部３Ａとの連結部、即ち計測流路部３Ｃの整流器１０より上流側に整流板７を設けることも考えられる。 In the above-described embodiment, the rectifying plate 7 is provided in the inlet channel portion 3A, but the present invention is not limited to this. For example, it is also conceivable to provide the rectifying plate 7 on the upstream side of the rectifier 10 of the measurement flow path part 3C, that is, the connection part of the measurement flow path part 3C with the inlet flow path part 3A.

また、前述した実施形態は本発明の代表的な形態を示したに過ぎず、本発明は、実施形態に限定されるものではない。即ち、本発明の骨子を逸脱しない範囲で種々変形して実施することができる。 Further, the above-described embodiments are merely representative forms of the present invention, and the present invention is not limited to the embodiments. That is, various modifications can be made without departing from the scope of the present invention.

本発明のガスメータの一実施形態を示す概略断面図である。It is a schematic sectional drawing which shows one Embodiment of the gas meter of this invention. 図１のＩ−Ｉ線概略断面図である。It is the II sectional schematic sectional drawing of FIG. 計測流路部を外した状態での図１のＩＩ−ＩＩ線断面図である。It is the II-II sectional view taken on the line of Drawing 1 in the state where a measurement channel part was removed. 計測流路部を外した状態での図１のＩＩ−ＩＩ線部分断面図である。It is the II-II line | wire partial sectional view of FIG. 1 in the state which removed the measurement flow-path part. 整流板を外した状態での図３に示す断面図である。It is sectional drawing shown in FIG. 3 in the state which removed the baffle plate. 図４のＩＩＩ−ＩＩＩ線部分断面図である。FIG. 5 is a partial cross-sectional view taken along line III-III in FIG. 4. （Ａ）は整流板の正面図であり、（Ｂ）は（Ａ）に示す整流板のＰ１矢視図であり、（Ｃ）は（Ａ）に示す整流板のＰ２矢視図であり、（Ｄ）は（Ａ）に示す整流板のＰ３矢視図であり、（Ｅ）は（Ａ）に示す整流板のＩＶ−ＩＶ線断面図である。(A) is a front view of the current plate, (B) is a P1 arrow view of the current plate shown in (A), (C) is a P2 arrow view of the current plate shown in (A), (D) is a P3 arrow view of the current plate shown in (A), and (E) is a sectional view taken along line IV-IV of the current plate shown in (A). 他の実施形態におけるガスメータの部分断面図である。It is a fragmentary sectional view of the gas meter in other embodiments. 従来のガスメータの概略構造及び作用を説明するための説明図である。It is explanatory drawing for demonstrating the schematic structure and effect | action of the conventional gas meter. 図９に示すガスメータの斜視図である。It is a perspective view of the gas meter shown in FIG. （Ａ）は理想的な計測流路部内の流量分布を示す説明図であり、（Ｂ）は遮断弁を正面から取り付けたガスメータにおける計測流路部内の流量分布を示す説明図である。(A) is explanatory drawing which shows the flow volume distribution in an ideal measurement flow path part, (B) is explanatory drawing which shows the flow volume distribution in the measurement flow path part in the gas meter which attached the cutoff valve from the front. 流量に対する図１０に示すガスメータによる流量計測に用いられる流量係数を示す流量性能グラフである。11 is a flow rate performance graph showing a flow coefficient used for flow rate measurement by the gas meter shown in FIG. 10 with respect to the flow rate.

Explanation of symbols

１ガスメータ
２Ａガス流入口
２Ｂガス流出口
３Ａ入口流路部
３Ａ２段差部
３Ｂ出口流路部
３Ｃ計測流路部
４弁座部
５遮断弁
７整流板
７Ａ第１の突起部
７Ｂ第２の突起部
８ボス
１２ゴムブッシュ（弾性部材）
１２Ａ溝 DESCRIPTION OF SYMBOLS 1 Gas meter 2A Gas inflow port 2B Gas outflow port 3A Inlet flow path part 3A2 Step part 3B Outlet flow path part 3C Measurement flow path part 4 Valve seat part 5 Shut-off valve 7 Current plate 7A 1st projection part 7B 2nd projection part 8 Boss 12 Rubber bush (elastic member)
12A groove

Claims

An inlet channel portion that communicates with the gas inlet and is provided in the vertical direction; and a valve seat portion that is provided in the inlet channel portion and has an opening through which gas flows from the front surface to the back surface or from the back surface to the front surface. A shut-off valve that abuts the valve seat portion and closes the opening to shut off the gas flow; an outlet passage portion that communicates with the gas outlet and is provided in a vertical direction; and a flow velocity sensor, A measurement channel provided horizontally between the inlet channel and the outlet channel, and a rectifying plate provided horizontally so as to be in contact with the inner wall of the connection between the inlet channel and the measurement channel And a gas meter comprising:
The rectifying plate is provided with a first protruding portion that protrudes from the downstream side in the gas flow direction at the opening of the valve seat portion toward the gas outlet side of the end portion on the gas outlet side. A gas meter characterized by

The connection part of the inlet channel part and the measurement channel part is provided so that the channel spreads toward the upstream side in the gas flow direction at the opening of the valve seat part,
The rectifying plate is provided with a second protruding portion that protrudes from the upstream side in the gas flow direction at the opening of the valve seat portion toward the gas outlet side among the ends on the gas outlet side. The gas meter according to claim 1, wherein:

The inlet channel portion provided in the vertical direction in communication with the gas inlet, the outlet channel portion provided in the vertical direction in communication with the gas outlet, and the inlet channel portion provided with a flow velocity sensor And a measurement flow path portion provided in a horizontal direction between the outlet flow path portions, and a rectifying plate provided horizontally so as to be in contact with an inner wall of a connection portion of the inlet flow path portion and the measurement flow path portion. Gas meter
The connection part of the inlet channel part and the measurement channel part is provided so that the channel spreads toward the front side or the back side,
The rectifying plate is provided with a second protruding portion that protrudes from the end of the gas outlet side toward the gas outlet side from the side in which the flow path expands most at the connecting portion. A characteristic gas meter.

A stepped portion is provided on the inner wall in contact with the rectifying plate at the connecting portion of the inlet flow channel portion and the measurement flow channel portion so that the upstream side protrudes toward the flow channel center.
The gas meter according to any one of claims 1 to 3, wherein the rectifying plate is mounted on the stepped portion.

The sealing agent is applied to a gap between the inner wall that is in contact with the rectifying plate and the rectifying plate at a connection portion between the inlet channel portion and the measurement channel portion. The gas meter according to item 1.

A groove in which an end portion of the gas inlet side, the front surface side, and the back surface side of the rectifying plate is fitted to an inner wall in contact with the rectifying plate at a connection portion of the inlet channel portion and the measurement channel portion. The formed elastic member is provided. The gas meter according to any one of claims 1 to 3, wherein the formed elastic member is provided.

A boss protrudes along the gas flow direction on the inner wall of the connection portion of the inlet channel portion and the measurement channel portion,
The gas meter according to any one of claims 1 to 6, wherein the rectifying plate is screwed to the boss.

The gas meter according to claim 7, wherein a side surface of the boss is provided in an R shape.

The gas meter according to any one of claims 1 to 8, wherein an end face of the current plate is provided in an R shape.