Packing integrated check valve and packing attachment member used therefor

Abstract

To solve the following problem: with respect to a packing integrated type check valve set on a primary side of a water meter, a flange body fitted to a rear end of a cartridge cage is pinched and stored on a secondary side end surface of a storage space provided for a secondary side end of a telescopic pipe unit and a primary side end surface of the water meter, and cutoff / density of a telescopic pipe inner peripheral part and a cartridge cage outer periphery part is maintained by an O-ring, but exchanging check valves requires exchanging telescopic pipes, and crimping and using of the O-ring for a long term causes the O-ring to adhere to the telescopic pipe and makes it hard to remove it when exchanging water meters and the like.SOLUTION: A packing integrated type check valve is provided with a check valve body contact valve seat 5 with an end side formed into a tapered part. A cylindrical cartridge body 1 is assembled with a packing fitting member with a packing 7 attached at a rear end of a packing fitting member 4 that brings the check valve body 2 into contact with the valve seat 5 by a spring 3 whose center part has a check valve shaft inserted in and which is energized in a stretch direction.SELECTED DRAWING: Figure 1

Description

[Technical field]

[0001] The present invention relates to a gasket-integrated check valve that is installed via an expansion pipe on the primary side of a water meter, and a gasket mounting member used therefor. [Background technology]

[0002] With regard to a gasket-integrated check valve to be installed on the primary side of a water meter, Patent Document 1 proposes that a flange body attached to the rear end of a cartridge cage be clamped and fitted between the secondary end face of the fitting space provided at the secondary end of the telescopic pipe unit and the primary end face of the water meter, with the watertightness and tightness of the inner periphery of the telescopic pipe and the outer periphery of the cartridge cage being maintained by an O-ring.

[0003] In the description of Patent Document 2, a check valve is attached inside a cylinder integral with the flange portion, and similarly to Patent Document 1, the cylindrical inner circumference and an O-ring are responsible for preventing backflow. [Prior art documents] [Patent documents]

[0004] [Patent Document 1] Patent No. 6228429 [Patent Document 2] Design Registration No. 1092792 Summary of the Invention [Problem to be solved by the invention]

[0005] However, the packing flange body in Patent Documents 1 and 2 is attached to the rear end of the cartridge cage to strengthen the support force against the flow pressure from the primary side to the secondary side, and the cartridge cage is fitted into a fitting space provided at the secondary end of the telescopic pipe unit so that the flange body is snap-fitted to the rear end of the cartridge cage, which creates the problem that when the check valve is replaced, the telescopic pipe also needs to be replaced with one that is suitable for the check valve.

[0006] Regarding the continued use of existing expansion pipes, there are problems such as discoloration of the inner diameter due to the long-term flow of tap water, the adhesion of foreign matter and the occurrence of corroded areas such as verdigris due to the chlorine contained in tap water, and furthermore, continued use is not possible in cases where the inner diameters of the expansion pipe units are different, the casting surface is exposed because the inner diameter is formed from casting, and it is difficult to prevent backflow with O-rings, etc. However, there are still requests for continued use, such as covering the cost of replacing the expansion pipes and water-stopping measures such as O-rings on the inner surface of the expansion pipes.

[0007] In addition, since the cartridge cage is directly supported by the flange body, the length of the sliding support portion of the check valve shaft needs to be long. Furthermore, since the watertightness and tightness between the inner circumference of the telescopic pipe and the outer circumference of the cartridge cage are maintained by an O-ring, there is a problem that the O-ring becomes stuck to the telescopic pipe after long-term crimping use, such as when replacing the water meter, and becomes difficult to remove. [Means for solving the problem]

[0008] The present invention provides a check valve mechanism having a check valve body abutted against the check valve packing by a spring biased in the tensile direction with a check valve shaft inserted through the centre, the check valve mechanism being inserted, via a packing mounting member, into a cylindrical cartridge body having a check valve seat formed on a tapered section at the front end and a flange body section at the rear end on which a packing is attached, so that the combination of the telescopic pipe unit and the packing-integrated check valve is not limited, and an O-ring is not used to prevent backflow on the inner periphery of the telescopic pipe. The invention provides a check valve mechanism having a check valve seat formed on a tapered section at the front end and a flange body section on which a packing is attached at the rear end, the check valve mechanism being inserted, via a packing mounting member, so that a check valve mechanism for use upstream of a water meter is configured to stop water flow with the check valve body, spring, check valve packing, cartridge body and check valve seat inside the packing-integrated check valve. Effect of the Invention

[0009] This makes it easy to replace or install the check valve with integrated packing even if the inside diameter of the telescopic pipe is corroded, the inside diameter dimensions differ due to differences in manufacturers, the pipe is manufactured with a cast surface, etc. Furthermore, by eliminating the O-ring shown by reference number 17 in the invention described in Patent Document 1, which maintains watertightness and tightness between the inside circumference of the telescopic pipe and the outside circumference of the cartridge cage, the problem of the O-ring becoming stuck to the telescopic pipe and becoming difficult to remove due to long-term crimping use when replacing a water meter, etc., is also eliminated.

[0010] Making the cartridge body cylindrical has the advantage that the length of the pillar supporting the sliding support part of the check valve shaft can be made shorter and parts can be manufactured more easily than when the flange body and cartridge cage are integrated as in the invention described in Patent Document 1. However, making the cartridge body cylindrical restricts the volume of the water passage (cross-sectional area for water flow), and an increase in pressure loss due to water flow becomes a problem.

[0011] Therefore, in the present invention, a configuration was considered that suppresses the increase in pressure loss while making the cartridge body cylindrical. If the increase in pressure loss can be suppressed, it will be possible to use it in places with low water supply pressure and to make the water supply facility smaller. The Japan Water Works Association standard JWWA B 129 water supply backflow check valve specifies the maximum pressure loss when used in a water supply system. The present invention is configured to comply with the above standard by forming the tip of the packing mounting member that receives the check valve body into a tapered section to suppress the increase in pressure loss. [Brief description of the drawings]

[0012] [Figure 1] 1 is a corresponding diagram showing a cross-sectional view of a check valve in a water-stopped state according to an embodiment of the gasket-integrated check valve of the present invention and a right side view thereof. FIG. [Diagram 2] FIG. 2 is a cross-sectional view of the check valve of FIG. 1 in a water-passing state. [Diagram 3] FIG. 2 is an exploded view showing the components of the packing-integrated check valve according to the present invention, showing a cross-sectional view of a packing mounting member and an external view of its outer surface. [Figure 4]FIG. 2 is an exploded view showing the components of the integral packing check valve according to the present invention, in which a front view, a right-side cross-sectional view, and an external view and a rear view of the packing mounting member are correspondingly shown. [Diagram 5] FIG. 2 is an exploded view showing the components of the integral packing check valve according to the present invention, in which a front view, a vertical sectional view, and a rear view of the cartridge body are corresponding to each other. [Figure 6] FIG. 2 is an exploded side view showing a state in which the packing-integrated check valve according to the present invention is inserted into a stop valve via an expandable pipe. [Figure 7] FIG. 2 is an overall side view showing the gasket-integrated check valve according to the present invention with the essential parts cut away, omitting other piping to which a stop valve, an expansion pipe, and a water meter are sequentially connected. [Figure 8] FIG. 2 is a cross-sectional view of a gasket-integrated check valve showing a basic structure capable of ensuring the maximum value of pressure loss based on the regulations of the Japan Water Works Association standard, and a corresponding right side view of the same structure. [Figure 9] 9 is a design value table showing main design values ​​for each nominal diameter of an embodiment of the packing-integrated check valve having the cross-sectional structure of FIG. 8. DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS

[0013] FIG. 8 shows the cross-sectional structure of a check valve with integrated packing, which exhibits regulated structural values ​​that ensure that pressure loss is below the maximum value based on the Japan Water Works Association standard JWWA B 129. A column body 41 is formed in the packing mounting member 4, and there are two columns with a nominal diameter of 13 to 40. The tip that receives the check valve body 2 is formed into a tapered section 46 to prevent an increase in pressure loss.

[0014] As a result, for a nominal diameter of 20, the standard flow rate of the Japan Water Works Association standard JWWA B 129 is 38 [L / min] and the standard pressure loss value under the same standard is 20 [kPa] or less. It was confirmed that the above standard value was secured at 12 [kPa] when the structure of Patent Document 1 was used, and at 14 [kPa] when the cylindrical cartridge body of this invention was used.

[0015] An embodiment of the present invention will be described in detail below with reference to the drawings. Reference numeral 1 denotes a cartridge body forming the outer shell of the check valve cartridge. A check valve seat 5 that receives a check valve element 2 having a tapered tip is attached to the primary side. A packing mounting member 4 is attached to support the check valve element 2, which comes into contact with the check valve seat 5 and check valve packing 6 to open and close, by being biased toward the primary side by a spring 3.

[0016] The tip of the outer diameter side of the check valve seat 5 is formed into a tapered surface, but by providing a two-face width portion, it is possible to easily assemble the cartridge body 1 and the packing mounting member 4 by screwing them together.

[0017] A flange portion is formed at the secondary end of the packing-integrated check valve, which is composed of a flange body 13 and a flange body 44 formed at the secondary end of the packing attachment member 4. A packing 7 made of an elastic material such as rubber is attached to the flange body. The flange portion may be formed only by the packing attachment member 4 or the flange body of the cartridge body 1.

[0018] The packing mounting member 4 is attached to the cartridge body 1, and its primary side end portion has a sliding support 42 formed in the center, and a valve shaft insertion hole 43 passes through the center of the sliding support 42, through which the valve shaft 21 of the check valve body is inserted and guided. Thus, the check valve shaft 21 is inserted into the valve shaft insertion hole 43, allowing the check valve body 2 to be opened and closed by the spring 3.

[0019] The number of support columns 41 of the packing mounting member 4 is preferably as small as possible since it restricts the cross section of water passage inside the check valve cartridge, and is about two for nominal diameters of 13 to 40, and at most about four. A male thread 45 is provided on the secondary side of the packing mounting member 4, which screws into the female thread 12 provided on the secondary side of the cartridge body 1 to form a packing-integrated check valve.

[0020] By setting the gap between the outer diameter of the column 41 of the gasket mounting member 4 and the inner diameter of the cartridge body 1 to 0.01 to 0.3 mm, the check valve body is positioned at the center of the water flow diameter, improving backflow prevention performance and preventing wear on the check valve body.

[0021] By setting the gap between the check valve shaft insertion hole 43 of the gasket mounting member 4 and the check valve shaft 21 of the check valve body 2 to 0.01 to 0.3 mm, the check valve body is positioned at the center of the water flow diameter, improving backflow prevention performance and preventing wear on the check valve body.

[0022] In the present invention, the structure of the packing-integrated check valve is such that a check valve seat 5 and the like are set at the primary end of the cartridge body 1 as shown in Fig. 8. If the inner diameter of the telescopic pipe and ΦB are the dimensional values ​​in Fig. 9, the diameter ΦA of the inlet part is set to 1.05 to 1.5 times ΦB, and the inner diameter part near where the check valve element is fully open is expanded by an angle of 15 to 90° with the central axis of the cartridge body 1 as the base axis to increase the diameter, so that ΦC is set to 1.3 to 1.8 times ΦB and ΦD is set to 0.7 to 0.95 times ΦC, thereby solving the problem of pressure loss.

[0023] The gasket-integrated check valve constructed as described above is installed by closing the existing stop valve P connected to the water meter M, removing the water meter M, and attaching it to the existing telescopic pipe S. After installation, the cap nut N attached to the telescopic pipe S is joined to the water meter M, and the stop valve P is opened. [Industrial Applicability]

[0024] The integral packing check valve and the packing mounting member used therein according to the present invention can be used extremely effectively in the water equipment industry, since, as described above, the integral packing check valve can be easily replaced or installed even in new installations or during piping in cases where the inner diameter of the telescopic pipe has been corroded, there are differences in the inner diameter dimensions due to differences in manufacturers, or the pipe is manufactured with a cast surface. [Explanation of symbols]

[0025] 1 Cartridge body 11 Cartridge body flange body 12 Female thread that mates with the male thread of the packing mounting member 13 Female thread that mates with the male thread of the check valve seat 14 Inner diameter part near the check valve body when it is fully open 2. Check valve 21 Check valve shaft 22 Tapered portion of check valve tip 3. Spring 4 Packing mounting material 41 Support column for packing mounting member 42 Sliding support for guiding the check valve shaft 43 Check valve shaft insertion hole 44 Flange body of packing mounting member 45 Male thread that mates with the female thread of the cartridge body 46 Tapered portion of packing mounting member 5 Check valve seat 6. Check valve packing 7 Packing M Water Meter N Cap nut P Stopcock S telescopic tube

Claims

1. A check valve with an integrated packing is formed by inserting a check valve mechanism into a cylindrical cartridge body having a check valve seat formed in a tapered section that narrows in diameter in the water flow direction at the tip side and a flange body section at the rear end where a packing is attached, the check valve mechanism having a check valve body abutted against the check valve packing by a spring that is biased in the tensile direction and a check valve shaft inserted through the center, via a packing mounting member formed in a tapered section at the tip that widens in diameter in the water flow direction.

2. A packing mounting member that is configured by supporting a sliding support part with an insertion hole in the center for slidingly supporting the check valve shaft on a flange body that covers the peripheral end surface with a packing, by a support column formed with a tapered part at the tip that expands in diameter in the water flow direction.

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