JP2006234777A - Back flow preventing component having straightening effect of water meter - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a back flow preventing component having a straightening effect of stopping stream when a water meter is reversely attached and stabilizing the stream when the water meter is normally attached. <P>SOLUTION: The back flow preventing component comprises a ring 6 capable of being engaged with an inflow port of the water meter, a lower opening/closing lid 1 and upper opening/closing lid 2 having a semi-circular plate shape that tightly come into contact with the inner wall of the ring 6, and a spring 4 using a pivot 3 as a power point. When it is reversely attached, the stream is stopped by a back flow preventing function of the lower opening/closing lid 1 and upper opening/closing lid 2. When it is normally attached, the stream is straightened by the lower opening/closing lid 1 and upper opening/closing lid 2. <P>COPYRIGHT: (C)2006,JPO&NCIPI

Description

  The present invention is a reverse installation that can occur when the water meter is replaced, that is, when the inlet and outlet of the water meter are mounted reversely with respect to the inflow side and the outflow side of the pipe, The present invention relates to a backflow prevention component having a rectifying effect of a water meter that stabilizes the water flow.

  Water meters are under the control of local governments, and the expiration date is set at 8 years under the Measurement Law. Water meters are usually replaced by water works contractors designated by local governments on behalf of the municipal water bureaus, etc. The so-called reverse installation of a water meter in which the positional relationship is unclear or the water meter inlet is connected to the inflow side of the pipe and the water meter outlet is connected to the outflow side of the pipe due to carelessness of the water supplier. Accidents occur every year. If the water meter is reversed, the integrated value that is the basis for collecting water charges will be reversed, making it impossible to collect water charges appropriately.

  Regardless of single box type tangential flow impeller type water meter or double box type tangential flow type impeller type water meter, the water meter senses the movement of water flow in one direction and integrates the amount of water used. . An inlet and an outlet of the water meter pass through, and a pivot is fixed in the middle part, and an impeller is mounted so as to be rotatable in the horizontal direction with the pivot as a pivot. The tap water flowing in from the inlet has a structure that is tangential to the blades of the impeller and pushes in a fixed position. Normally, the impeller rotates counterclockwise. The rotational movement of the impeller is a non-contact type magnetic coupling between the magnet mounted at the upper center of the impeller and the magnet gear magnet that is part of the gear mechanism housed above the impeller. It is structured to be linked. In the gear mechanism, the rotational movement of the magnet gear is structured to be displayed in an integrated manner in conjunction with a plurality of gears having the calculated number of teeth so that the amount of water used is correctly displayed. Therefore, when the inlet and outlet of the water meter are mounted in the direction opposite to the water flow direction of the pipe, the impeller of the water meter is reversely rotated and cannot be correctly integrated.

The standard flow rate of a water meter is determined by the diameter, but depending on the influence of water pressure from the mains, the location of the water meter, and the open / close state of the inflow valve, the water flow through the pipe and the water meter is below the standard flow rate. In some cases, a water meter called a short having a total length of 100 mm may have a complicated water flow because the straight cylindrical portion constituting the inner wall on the inflow side is short. The water flow below this standard flow rate, that is, the minimum flow rate used or a water meter with a short straight cylindrical part is not in a state where the water flow through the pipe is full, so the water flow becomes irregular and tangential to the impeller blades of the water meter In addition, there is a case where the water meter is not pushed by being collided with a certain position, and the total of the water meter is not accurately displayed.

  As a conventional method for preventing the backflow of a water meter, for example, there is a method described in Japanese Patent Laid-Open No. 11-201785. According to this conventional method, in the vicinity of the outlet of the meter main body, the flow path is opened so that tap water flows out when water is supplied, and the tap water that flows backward from the house when water is shut off does not enter the meter main body. The check valve is equipped with a valve body that is pushed by water pressure and a valve frame body that slidably holds the valve body in the center. ing. The head of the valve body is urged to the left side by a coil spring so as to close a valve opening portion that becomes a tap water flow path formed on the upstream side of the valve frame body. One end of the coil spring is abutted against the head of the valve body, and the other end is abutted against the receiving frame and is elastically mounted. When the tap water is fed through the meter body, the valve body is pushed to the outflow side against the urging force of the coil spring by water pressure to open the valve opening and tap water to the outlet. It is designed to flow out.

  Moreover, as a method of rectifying the inflow side water flow in the water meter, for example, there is a method described in JP-A-2003-50143. According to this conventional method, the rectifying member is provided in the inflow side nozzle of the water meter. The rectifying member is, for example, a rectangular tube having a square cross section, and is formed by bending one end straight along the stepped portion and the other end along the inner peripheral surface of the measuring chamber. A pair of long latching pieces are cut and raised on the upper and lower sides of one end, and a pair of short latching pieces are similarly cut and raised on the upper and lower sides of the other side. This rectifying member is not limited to a rectangular tube having a square cross section, and may be formed in a rail shape having an H cross section, for example, by connecting plate members by welding or the like.

  In the conventional method for preventing the backflow of the water meter, since the check valve is built in the outflow side, the water flow entering from the inflow side of the water meter causes an increase in speed on the outflow side. As a result, Bernoulli's theorem A reduction in pressure will occur. Here, since the check valve is mounted in the vicinity of the impeller of the water meter, the water flow that should normally collide with the blade of the impeller of the water meter and push the blade is caused by the Venturi effect. It will be in the state attracted | sucked to the outflow side, and will influence the rotation of the said impeller. In addition, the check valve which is an embodiment of the conventional method has a structure in which a slidable valve body is pushed by water pressure and is opened and closed by a coil spring. Although the water flow in the meter is instantaneous, it is interrupted, resulting in a change in the rotation of the impeller. Furthermore, the above condition is an instrumental inspection item (difference between the displayed amount of the water meter and the amount of water actually flowed) and pressure loss (pressure difference between the inflow side and the outflow side), which are inspection items of the measurement method indispensable for practical use of water meters. It will also affect the test.

  Further, the conventional method relating to the rectification of the water meter is such that a rectangular tube having a square cross section or an H-shaped rail-shaped rectification member is mounted along the inflow side inner wall, so that the amount of water passing through the water meter is a standard flow rate. However, when the amount of water is the minimum flow rate, the water flow that passes through the water meter does not fill the inner wall of the inflow side. As a result, the impulsive water flow is dispersed and the impulsive force on the blades of the impeller is dispersed, which affects the rotation of the impeller.

  In order to solve the above-mentioned problem, in the present invention, the inner diameter of the water meter is a hollow ring having an outer diameter that can be fitted, and the ring thickness extension direction is located at a substantially central portion of the ring. There is a pair of holes in the peripheral wall on the ring diameter line, and a rod-shaped pivot can be fitted into the hole, and the shape can be rotated around the pivot in the ring after assembly. A semicircular plate-like upper opening / closing lid that is in close contact with the inner ring wall and a semicircular plate-like lower opening / closing lid that is rotatable about the pivot axis and whose shape is in close contact with the inner ring wall is a spring centered on the pivot Thus, the upper opening / closing lid is pushed and biased so that the upper opening / closing lid is rotated approximately 90 degrees upward from the horizontal position in the outlet direction, and the lower opening / closing lid is rotated approximately 90 degrees downward from the horizontal position in the outlet direction, On the inner wall of the ring, the upper open / close lid and the lower open / close lid Protruding stoppers that stop at a position on a substantially vertical line are provided at the top and bottom, and when the ring is fitted on the inflow side inner wall of the water meter and mounted on the outer wall of the ring, the pivot is horizontal and the upper part is A backflow prevention component having a rectifying effect, wherein the opening / closing lid has a shape that can be locked so that the opening / closing lid is in an upper position and the lower opening / closing lid is in a lower position.

According to the backflow prevention component having a rectifying effect of the present invention, when the water meter is intentionally or accidentally attached to the inflow side and the outflow side, the tap water flowing from the outlet of the water meter is impeller chamber of the water meter. To reach the inflow side. At this time, the upper opening / closing lid and the lower opening / closing lid of the present invention fitted and attached to the inflow side are swelled by the spring to close the inner wall of the inflow side and are further pushed by the water pressure flowing in from the outflow side. However, since the rotation is stopped by the stopper, the inlet is closed. As a result, since the water flow is stopped, the water meter installation installer easily understands the reverse state of the water meter, and since the water flow is stopped, the user cannot use the water. There is no subtraction.
The impeller rotates in the reverse direction until the tap water flowing in from the outflow side in the reversely attached state of the water meter passes through the impeller chamber and stops at the backflow prevention component having the rectifying effect of the present invention. Since it is the amount of water, it is within the tolerance range of +/- 2% defined by the metering method of water meters.
Further, when the water meter equipped with the present invention is normally attached, the tap water flowing in from the inflow port is swelled by the spring of the present invention to close the inflow side inner wall and the upper opening / closing lid and the lower opening / closing Although colliding with the lid, the upper open / close lid is rotated from the upper vertical position to the outflow side by the water pressure of tap water, and the lower open / close lid is rotated from the lower vertical position to the outflow side, so that the inner wall on the inflow side is opened. Tap water flows into the impeller chamber of the water meter. In this state, the obstacle to the water flow is the thickness of the pivot of the present invention, the upper opening / closing lid, and the lower opening / closing lid, but since the cross section is slight, the water flow is not affected. Furthermore, since the amount of water that has passed through the parts of the present invention on the inflow side pushes the impeller of the water meter, the integrated value of the water meter is not affected.

  Further, according to the backflow prevention component having a rectifying effect of the present invention, when the amount of water flowing from the inflow side of the water meter is a minimum usage flow rate, for example, less than half of the cross-sectional shape, or a straight cylinder constituting the inflow side of the water meter Even if the water flow is complicated because the part is short, the upper opening and closing lid and the lower opening and closing lid that are urged so as to close the inflow side inner wall according to the present invention according to the amount of water. The water flow is stable. As a result, the water meter always impinges on the blade of the impeller of the water meter in a tangential direction and is pushed and pushed, so that the total of the water meter is accurately displayed.

  Water meters are managed by local governments, and their shapes and specifications are unified by local governments from the viewpoint of recycling and using water meter parts, except for worn parts. The backflow prevention component having a rectifying effect of the present invention has an advantage that it can be used simply by fitting into the inflow side inner wall of a water meter without changing the shape and specification standardized by each local government.

  Hereinafter, specific examples of the present invention will be described with reference to the drawings. However, the following examples are merely examples and do not limit the scope of the present invention.

FIG. 1 is a sectional view of a water meter. An inflow port 18 having a circular cross section and an outflow port 19 having a circular cross section are provided at the lower portion of the lower case 7. The outer periphery of the end portions of the inlet 18 and the outlet 19 are screwed and connected by piping parts so that tap water from the main pipe flows consistently. Since this example is a single box type tangential flow impeller type water meter, the cross section of the inlet 18 in the cross section of the inner wall of the inflow side has a larger diameter for the purpose of fitting and fixing the strainer 12 than the cross section of the outlet 19 direction. However, the backflow prevention component having the rectifying effect of the present invention may be fitted and fixed in front of the strainer 12. 6 is a ring body of the present invention, 2 is an upper opening / closing lid, and 1 is a lower opening / closing lid. In this figure, the spring, pivot, and stopper, which are other components of the present invention, are not shown. A pivot 15 is provided at the center of the inner bottom surface of the lower case 7 and is fixed vertically to the inner bottom surface of the lower case 7. The pivot 15 is supported and the impeller 11 having the magnet 16 is rotatably accommodated in the upper center portion, and the register box 8 is assembled to the upper portion in a state of being close to the magnet 16.
A gear having a magnet 17 is rotatably mounted inside the register box 8 with the bottom wall of the register box 8 interposed therebetween, and the rotational movement of the impeller 11 is transferred to the gear in the register box 8 via the magnet 16 and the magnet 17. It is a structure that is transmitted in the state of magnet coupling. The gear in the register box 8 is composed of a plurality of gears whose number of gear teeth is calculated so that the flow rate of tap water passing through the inlet 18 is correctly displayed. An upper portion of the register box 8 has a counting display unit 13 for displaying the amount of water, and a glass plate 14 is attached to the upper surface so that the counting display unit 13 can be visually seen. The upper case 9 is screwed to the lower case 7 with a gasket (not shown) interposed therebetween, and the register box 8 is fastened and fixed. A lid 10 having a pivot is provided on the upper surface of the upper case 9 so as to be openable and closable, and constitutes a water meter equipped with a backflow prevention component having a rectifying effect of the present invention. Since FIG. 1 is a single box type tangential flow impeller water meter, it has a step on the inner wall on the inlet 18 side, and the step is used to insert and fix the backflow prevention component having the rectifying effect of the present invention. However, in the case of a multi-box type tangential flow impeller type water meter without a step, a plurality of convex elastic locking parts are provided on the outer wall of the backflow prevention part having the rectifying effect of the present invention and are fitted into the inflow side inner wall. It may be fixed.

  FIG. 2 is a front view of the F part of FIG. 1 as viewed from the impeller 11 side. The outer periphery of the ring body 6 is formed in close contact with the inner wall on the inlet side (not shown), the wall of the ring body 6 on the horizontal diameter line has a pair of holes, and the pivot 3 is fitted into the hole. . A semicircular plate-like upper opening / closing lid 2 is pivotably mounted above the pivot 3 and a semicircular plate-shaped lower opening / closing lid 1 is pivotally mounted below. Both the upper opening / closing lid 2 and the lower opening / closing lid 1 have outer shapes that are in close contact with the inner wall of the ring body 6. Further, a spring 4 is attached by applying a force to the pivot 3 to push the upper opening / closing lid 2 upward and the lower opening / closing lid 1 downward to be locked by stoppers 5. A convex elastic locking part may be provided on the outer wall of the ring body 6 in order to fix the pivot 3 in a horizontal state.

  FIG. 3 is a three-dimensional view of the main body of the present invention. The ring main body 6 has a pair of holes on the horizontal diameter line at a substantially central portion in the thickness extension direction, and the pivot 3 is fitted. The upper opening / closing lid 2 is mounted so as to be capable of rotating 90 degrees upward from the horizontal position about the pivot 3, and the lower opening / closing lid 1 is mounted so as to be capable of rotating 90 degrees downward from the horizontal position. The spring 4 is urged so as to spread the upper opening / closing lid 2 and the lower opening / closing lid 1 with the pivot 3 as a power point. FIG. 3 shows a state in which the backflow prevention component having the rectifying effect of the present invention is fitted and installed from the inlet of a water meter (not shown) and the tap water is appropriately flowing from the left-hand direction on the center axis extension of the ring body. The upper opening / closing lid 2 and the lower opening / closing lid 1 which are biased by the spring 4 by the water pressure of the flowing water and block the inside of the ring body 6 are rotated and opened in the direction of the central axis, respectively. Yes.

  FIG. 4 is a water flow state diagram at the time of the minimum flow rate in FIG. 1F. Since the water flow (arrow A) flowing in from the inflow port 18 does not satisfy the inner diameter of the inflow port 18, it flows through the lower portion of the inner diameter (arrow B) and passes through the lower opening / closing lid 1 (arrow C). Although the water flow at the minimum flow rate is irregular, the lower opening / closing lid 1 adjusts the opening state according to the amount of water passing therethrough, so that the water flow after passing through the lower opening / closing lid 1 is stabilized and the flowing water is rectified. Here, 7 is a lower case, 18 is an inlet, 12 is a strainer, and 11 is an impeller. FIG. 4 is an example of the single box tangential flow impeller water meter of FIG. 1 and therefore has a step on the inner wall on the inlet 18 side, and can be closely fitted to the inner wall of the step. 4 is an embodiment in which the strainer 12 is fitted and mounted after fitting and mounting the backflow prevention component having the rectifying effect of the present invention.

  FIG. 5 is a water flow state diagram at the maximum flow rate in FIG. 1F. Since the amount of water (arrow A) is large and the water pressure is high, the upper opening / closing lid 2 and the lower opening / closing lid 1 both push the spring 4 and push the spring 4 in the center axis extending direction of the ring body 6, that is, the inlet 18. It is in a state where there is no obstacle to the flowing water which is located horizontally with respect to the direction of extension of the central axis and flows from the inlet 18. The strength of the spring 4 that urges the upper opening / closing lid 2 and the lower opening / closing lid 1 to rotate is not particularly specified, but when the amount of water is zero, the upper opening / closing lid 2 urges the pivot 3 by the urging of the spring 4. The shaft pivots upward as an axis and stops at an upper stopper 5 which is a locking part (not shown) so that the inside of the inflow port 18 can be closed above the pivot 3, and the lower opening / closing lid 1 is lowered with the pivot 3 as an axis. The tap water is stopped at a lower stopper 5 which is a locking part not shown in the drawing, and is strong enough to close the inside below the pivot 3 of the inlet 18, and the pressure in the normal water pipe is usually 1 Mpa. A strength of 0.2 kg inside / outside that can start turning at the minimum flow rate is appropriate.

FIG. 6 is a water flow state diagram when the part of FIG. 1F is reversed. Although not shown, the water flow that flows in from the outflow side passes through the impeller 11 and becomes a water flow indicated by an arrow E. Here, the upper opening / closing lid 2 and the lower opening / closing lid 1 close the inner wall of the inflow port 18 in a state where the inner wall on the inflow port 18 side is sealed substantially vertically by the force of the spring 4 spreading, and the water pressure of the arrow E Further, the upper opening / closing lid 2 and the lower opening / closing lid 1 are pushed, but the upper opening / closing lid 2 and the lower opening / closing lid 1 are also locked by a stopper (not shown) to block the inner wall. Accordingly, the water flow indicated by the arrow E does not flow into the inflow port 18 and the water flow is stopped. Here, the plate thickness of the upper opening / closing lid 2 and the lower opening / closing lid 1 is such that when the water meter is properly mounted and tap water flows in the direction of the impeller 11 from the inflow port 18, it does not obstruct the water flow as much as possible. Although the thickness should be reduced, since the test pressure resistance load of the water supply is 1.75 MPa, the bending strength of the upper opening / closing lid 2 and the lower opening / closing lid 1 is suitably 20 kgf / cm ² or more. When the water meter is reversed as shown in the example of FIG. 6, the water flow (arrow E) is reversed by the upper open / close lid 2 and the lower open / close lid 1 that are energized by the spring 4 and seal the inner wall on the inlet 18 side. In order to further block the inside of the inlet 18 with the water pressure of), the water flow that has flowed back stops. As a result, the water meter installer can easily recognize the reverse of the water meter, and since the water flow stops and the tap water cannot be used, the user can easily recognize the failure. .

Cross section of water meter Body front view Body 3D view Water flow diagram at minimum flow rate Water flow diagram at maximum flow rate Water flow diagram during reverse installation

Explanation of symbols

1 .... lower opening / closing lid 2 .... upper opening / closing lid 3 .... pivot 4 ... spring 5 .... stopper 6 ... ring body 7 ... lower case 8 ... ... Register box 9 ... Upper case 10 ... Lid 11 ... Impeller 12 ... Strainer 13 ... Count display 14 ... Glass 15 ... Pivot 16 ... Magnet 17 ... Magnet 18 ... Inlet 19 ... Outlet

Claims (3)

  A ring with a hollow inside that has an inside diameter that can be fitted with the inside diameter of the inflow side of the water meter, and has a pair of holes on the peripheral wall on the ring diameter line that is located at the approximate center of the ring in the ring thickness extension direction. The hole has a structure in which a rod-like pivot can be fitted, and can be rotated around the pivot in the ring after assembly, and the shape of the semi-circular plate is in close contact with the inner wall of the ring. The upper open / close lid and the semi-circular plate-shaped lower open / close lid, which is rotatable about the pivot axis and is in close contact with the inner wall of the ring, are springs with the pivot as a force point, and the upper open / close lid from the horizontal position in the outlet direction The lower opening / closing lid is pushed and biased so as to rotate upward by approximately 90 degrees and from the horizontal position in the outflow direction to rotate downward by approximately 90 degrees. Protruding strikes that cause the lid to stop at a position on a substantially vertical line When the ring is fitted on the inflow side inner wall of the water meter and mounted on the outer wall of the water meter, the pivot is horizontal, the upper opening / closing lid is upward, and the lower opening / closing lid is A backflow prevention component having a rectifying effect, characterized by having a convex elastic portion that can be locked at a lower position.   2. The backflow preventing part having a rectifying effect according to claim 1, wherein the structure according to claim 1 is built in an inflow side inner wall of a water meter.   The backflow prevention part having a rectifying effect according to claim 1 is characterized in that the structure according to claim 1 is integrally incorporated without providing a hollow ring on the inflow side inner wall of the water meter. Backflow prevention component with rectifying effect.

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