JP6301286B2 - Check valve - Google Patents

Description

  The present invention relates to a check valve installed in the middle of a water supply pipe.

  Such a check valve is described in Patent Document 1. The check valve of Patent Document 1 includes a valve box having a liquid inlet and a liquid outlet, a valve body that is housed in the valve box and opens and closes the fluid inlet, and an annular shape that protrudes outward from the valve box. A flange is provided. The valve box includes an annular valve seat portion having a liquid inlet, a bottom portion facing the liquid inlet on the downstream side in the flowing water direction, and three ribs connecting the valve seat portion and the bottom portion on the outer peripheral side of the valve body. Prepare. A liquid outlet is provided between the three ribs in the circumferential direction. The valve body moves between a closed position where the valve body abuts on the valve seat portion and closes the liquid inlet, and an open position where the valve body portion is separated from the valve seat portion downstream in the flowing water direction. The three ribs guide the valve body moving between the closed position and the open position from the outer peripheral side.

  The check valve is installed in a state where a flange is sandwiched between a primary side pipe (upstream side pipe) and a secondary side pipe (downstream side pipe) constituting a water pipe, and a valve box is inserted into the pipe. The valve body moves from the closed position to the open position due to the pressure of the fluid flowing in through the liquid inlet. When the valve body moves to the open position, the fluid flowing in from the liquid inlet flows out from the liquid outlet. When the inflow of fluid stops, the valve body returns to the closed position by the biasing force of the coil spring and closes the liquid inlet. This prevents backflow of fluid.

Japanese Patent No. 11-67998

  At the time of construction of piping, very rarely, fine foreign matters such as chips and sand from the piping may enter the piping. Here, in the check valve in which the valve box is inserted into the pipe, the liquid inlet is smaller than the inner diameter of the pipe, so that the flow rate increases when the fluid passes through the liquid inlet. Therefore, when foreign matter that has entered the pipe flows into the valve box from the liquid inlet, the foreign matter enters between the outer peripheral surface of the valve body and the inner peripheral surface of the rib and is sandwiched between them ( The check valve may be in a state in which foreign matter is caught.

  When the check valve bites in a foreign object, the movement of the valve body is hindered. As a result, problems such as a decrease in the function of preventing the back flow of the fluid and a decrease in the water flow rate occur in the check valve.

  The subject of this invention is providing the check valve which can prevent or suppress that a foreign material is bitten in view of such a point.

In order to solve the above problems, a check valve according to the present invention includes a valve box including an annular valve seat having a liquid inlet, and a closed position in which the valve inlet is closed in contact with the valve seat. And a valve body movable between an open position separated from the valve seat portion , and a flange projecting outward from the valve seat portion, and the valve box has the valve body on the outer peripheral side. A plurality of ribs extending from the valve seat portion in the moving direction of the valve body to guide the valve body at positions surrounded by the valve seat portion, and provided between the ribs in the circumferential direction toward the radially outer side of the ribs A valve-side facing surface, which is a region facing the rib-side facing surface in the outer peripheral surface of the valve body, and a rib-side facing surface that faces the outer peripheral surface of the valve body in each rib. one opposed face of the direction perpendicular to the contact portion capable of contacting the other opposing surface, the moving direction of the valve body And a relief portion spaced from the other opposing surface, said contact portion, characterized in that it is extended in the moving direction.

According to the present invention, the rib-side facing surface of the rib for guiding the valve body and the valve-body facing surface of the valve body are such that a contact portion provided partially on one facing surface is in contact with the other facing surface. It becomes. Accordingly, the contact area between the rib and the valve element is smaller than when the entire valve element facing surface is in contact with the entire rib side facing surface and the rib guides the valve element. Therefore, it can suppress that a foreign material is inserted | pinched between a rib and a valve body. In addition, even when a foreign object is sandwiched between the rib and the valve body, the contact area between the rib and the valve body is small, and the contact portion extends in the moving direction of the valve body (fluid flow direction) Foreign matter is not stable between the rib and the valve body. Accordingly, the foreign material flows out from between the rib and the valve body to the outside in the radial direction of the rib through the escape portion and the liquid outlet, and flows out downstream of the check valve. Thereby, it can prevent or suppress that a non-return valve will be in the state which has bitten the foreign material. Furthermore, since the contact part is extended in the moving direction of the valve body, the valve body can be guided by the contact part. Therefore, the behavior of the valve body that moves between the closed position and the open position is stabilized.

  In the present invention, in the cross section obtained by cutting the rib and the valve body in a direction orthogonal to the moving direction, it is desirable that the contact portion of the one facing surface is in contact with the other facing surface at a point. If it does in this way, the contact area of a rib and a valve body can be made very slight. Therefore, it is possible to further suppress the check valve from biting foreign matter. Moreover, it can suppress more that a non-return valve will be in the state which has bitten the foreign material.

  In the present invention, the one opposing surface may include a protrusion extending in the moving direction at the center in the circumferential direction, and the contact portion may be a tip of the protrusion. In this way, it is easy to provide relief portions on both sides of the contact portion in the circumferential direction.

In the present invention, each of the one opposing surfaces may include a plurality of the contact portions. In this way, since the valve body can be guided by the plurality of contact portions, the behavior of the valve body is easily stabilized. In this case, a groove extending in the moving direction is provided on the one opposing surface, and the contact portion may be edges on both sides in the circumferential direction of the groove. Alternatively, the one opposing surface may be provided with a ridge extending in the moving direction, and the contact portion may be a tip of the ridge.

  In this invention, the said contact part and the said escape part shall be provided in the said rib side opposing surface. In this way, even when the valve body that moves between the closed position and the open position rotates in the circumferential direction, the contact area between the valve body and the rib can be kept small.

  Moreover, in this invention, the said contact part and the said escape part may be provided in the said valve body side opposing surface. In this case, since it is not necessary to perform a process such as providing a relief portion on the rib, the rigidity of the rib can be maintained.

  ADVANTAGE OF THE INVENTION According to this invention, it can prevent or suppress that a non-return valve bites the foreign material which flows in the inside of piping.

It is a perspective view of the check valve of the present invention. It is sectional drawing of the perspective view of a non-return valve. It is a disassembled perspective view of a check valve. It is sectional drawing which cut | disconnected the check valve in the plane orthogonal to an axis line. It is explanatory drawing of the experimental equipment of the verification experiment which verifies the biting of the foreign material of a check valve, and sectional drawing of the check valve of a reference example. It is a table | surface of the experimental result of the verification experiment shown in FIG. It is sectional drawing of the check valve of the modification 1, 2, and the table | surface of the experimental result of verification experiment. It is sectional drawing of the non-return valve of the modifications 3, 4, and 5.

  Hereinafter, a check valve according to an embodiment of the present invention will be described with reference to the drawings.

  FIG. 1 is a perspective view of a check valve to which the present invention is applied. FIG. 2 is a cross-sectional view of the check valve installed in the middle of the water pipe. 2A shows a state where the valve body is in the closed position, and FIG. 2B shows a state where the valve body is in the open position. FIG. 3 is an exploded perspective view of the check valve.

  The check valve of this example is installed in the middle of the water pipe. As shown in FIG. 1, the check valve 1 includes a valve box 2, a valve body 3 housed inside the valve box 2, and a coil spring 4. The check valve 1 also has an annular flange 5 protruding from the valve box 2 to the outer peripheral side, and an annular rubber packing 8. The rubber packing 8 includes an annular recess 8a (see FIG. 2) that is recessed in the radial direction on the inner peripheral surface. The rubber packing 8 is in a state in which the flange 5 is inserted into the annular recess 8a, and is attached to the flange 5 from the outer peripheral side. In the following description, the direction of the axis L of the check valve 1 is the front-rear direction X, the side opposite to the side where the flange 5 is located is the front X1 (front side) of the check valve 1, and the side where the flange 5 is located Let it be the rear X2 (rear side) of the valve 1.

  As shown in FIGS. 1 and 2, the valve box 2 includes an annular valve seat portion 12 having an inflow port (liquid inflow port) 11 and a space between the valve seat portion 12 and a front X1 of the valve seat portion 12. The bottom part 13 arrange | positioned coaxially and the three ribs 14 which connect the valve seat part 12 and the bottom part 13 are provided. The three ribs 14 are provided around the axis L at equal angular intervals. Between each rib 14 in the circumferential direction, there is an outlet (liquid outlet) 15.

  As shown in FIG. 2, the valve seat portion 12 includes a tubular portion 17 and an annular valve seat packing 18 fixed to the inner peripheral side of the tubular portion 17. The valve seat packing 18 is a valve seat with which the valve body 3 abuts, and defines an opening edge on the front side of the inlet 11 in the valve seat portion 12. The three ribs 14 extend in the direction of the axis L from the front end edge of the cylindrical portion 17. The flange 5 protrudes radially outward from the rear portion of the cylindrical portion 17.

  The bottom portion 13 includes a circular end plate portion 21 that faces the inflow port 11, an annular tapered wall portion 22 that extends from the outer periphery of the end plate portion 21 toward the rear X 2 toward the outer periphery, and a central portion of the end plate portion 21. A support shaft 23 that protrudes from the shaft and extends coaxially with the tapered wall portion 22 is provided. The distal end of the support shaft 23 is located closer to the valve seat portion 12 than the rear end edge of the tapered wall portion 22. The three ribs 14 are continuous with the outer peripheral surface of the tapered wall portion 22. A step portion is provided at an intermediate position in the front-rear direction X of the inner peripheral surface of the tapered wall portion 22. The step is provided with an annular rearward surface 25.

  The valve body 3 includes a valve portion 27 that contacts the valve seat (valve seat packing 18) and seals the inflow port 11, and a shaft portion 28 that protrudes forward X1 from the valve portion 27. The valve portion 27 includes a circular plate portion 29 that is smaller than the inner diameter of the inflow port 11, an annular tapered plate portion 30 that expands from the outer peripheral edge of the circular plate portion 29 toward the outer periphery toward the front X 1, and the tapered plate portion 30. The cylindrical plate part 31 of the fixed width | variety extended from the outer peripheral edge part to the front X1 is provided. The shaft portion 28 protrudes from the central portion of the circular plate portion 29 and extends in the direction of the axis L forward X1. The end plate portion 21, the tapered plate portion 30, the cylindrical plate portion 31, and the shaft portion 28 are coaxial. The shaft portion 28 includes a center hole 28a. The center hole 28a extends from the front end surface of the shaft portion 28 along the axis L to the rear X2.

The valve body 3 is accommodated in the valve box 2 in a state where the support shaft 23 of the valve box 2 is inserted into the center hole 28 a of the shaft portion 28. The support shaft 23 supports the valve body 3 so as to be movable in the direction of the axis L. In the valve box 2, the valve body 3 moves in the direction of the axis L between a closed position 3 </ b> A that blocks the inlet 11 and an open position 3 </ b> B that is separated from the inlet 11 forward X <b> 1. 2A, the closed position 3A is a position where the circular plate portion 29 of the valve portion 27 is inserted into the inflow port 11 and the tapered plate portion 30 is in contact with the valve seat packing 18 of the valve seat portion 12. As shown in FIG. is there. In the open position 3B, as shown in FIG. 2B, the valve portion 27 is separated from the valve seat packing 18, and the front end edge of the cylindrical plate portion 31 is at the rear end edge of the tapered wall portion 22 of the bottom portion 13. It is the position where it abuts.

  Here, in a state where the valve body 3 is inserted into the valve box 2, the three ribs 14 can contact the outer peripheral surface 3 a of the valve body 3. More specifically, the three ribs 14 can come into contact with the outer peripheral surface 3 a of the cylindrical plate portion 31 of the valve portion 27. The three ribs 14 guide the valve body 3 moving between the closed position 3 </ b> A and the open position 3 </ b> B from the outer peripheral side of the valve body 3.

  The coil spring 4 is located on the outer peripheral side of the shaft portion 28 of the valve body 3. The rear end portion of the coil spring 4 contacts the valve portion 27 from the front X1. The front end portion of the coil spring 4 abuts the rearward surface 25 of the tapered wall portion 22 of the valve box 2 from the rear X2. Thereby, the coil spring 4 biases the valve body 3 to the closed position 3A. Here, since the coil spring 4 contacts the valve body 3, the valve body 3 does not rotate around the axis L while the valve body 3 moves between the closed position 3A and the open position 3B.

(Check valve assembly method)
As shown in FIG. 3, the valve box 2 and the flange 5 are composed of two members, a valve box main body 41 and an inlet defining member 42. The valve box body 41 is made of POM (polyacetal resin). The inlet defining member 42 is made of POM (polyacetal resin) or bronze alloy. The valve box body 41 includes a cylindrical plate portion 43 having a constant width, three ribs 14, and a bottom portion 13. The three ribs 14 extend from the front edge of the cylindrical plate portion 43 to the front X1. The bottom portion 13 connects the front end portions of the three ribs 14. Further, the valve box main body 41 includes a valve box main body side annular plate portion 44 that protrudes radially outward from the rear end of the cylindrical plate portion 43.

  The inflow port defining member 42 includes an inflow port defining member-side annular plate portion 46 in which the inflow port 11 is formed at the center, and a cylinder projecting forward X1 from the opening edge of the inflow port 11 in the inflow port defining member-side annular plate portion 46. A cylindrical packing support 47 is provided. The packing support part 47 supports the valve seat packing 18 on the outer peripheral side thereof. In a state where the valve seat packing 18 is supported by the packing support portion 47, as shown in FIG. 2, the valve seat packing 18 protrudes forward X 1 from the front end edge of the packing support portion 47.

  When assembling the check valve 1, first, the valve body 3 and the coil spring 4 are housed inside the valve box body 41. More specifically, the coil spring 4 is arranged on the outer peripheral side of the shaft portion 28 of the valve body 3, and the support shaft 23 is inserted into the center hole 28 a of the shaft portion 28 of the valve body 3 in this state. In parallel with this, the valve seat packing 18 is supported by the inlet defining member 42.

  Next, the valve seat packing 18 and the packing support portion 47 are inserted into the cylindrical plate portion 43 from the rear X2 of the valve box main body 41, and the inlet port defining member side annular plate portion 46 is inserted into the valve box main body side annular plate portion. 44. As a result, as shown in FIG. 2, the packing support portion 47 of the inlet defining member 42 and the cylindrical plate portion 43 of the valve box body 41 constitute a cylindrical portion 17 of the valve seat portion 12. The valve seat packing 18 is fixed to the inside of the cylindrical portion 17 while being sandwiched from both sides in the radial direction by the packing support portion 47 of the inlet defining member 42 and the cylindrical plate portion 43 of the valve box body 41. The inflow defining member-side annular plate portion 46 and the valve box body-side annular plate portion 44 constitute a flange 5 that protrudes from the valve seat portion 12 to the outer peripheral side. Here, the rubber packing 8 is fitted into the flange 5 from the outer peripheral side of the flange 5 and covers the front end face and the rear end face of the flange 5.

(Shape of rib side facing surface)
Next, the shape of each rib 14 will be described with reference to FIG. FIG. 4 is a cross-sectional view when the check valve 1 is cut by a plane orthogonal to the axis L and passing through the rib 14 and the cylindrical plate portion 31 of the valve body 3. In FIG. 4, the check valve 1 is viewed from the front X1. As shown in FIG. 4, each rib 14 includes a rib-side facing surface 51 that faces the outer peripheral surface 3 a of the valve body 3 (the outer peripheral surface 3 a of the cylindrical plate portion 31 of the valve portion 27). Further, the valve body 3 includes a valve body-side facing surface 52 which is a region facing the rib-side facing surface 51 on the annular outer peripheral surface 3 a of the cylindrical plate portion 31 of the valve portion 27.

  The rib side facing surface 51 includes a ridge 54 extending in the direction of the axis L in the central portion in the circumferential direction. The protrusion 54 is provided in the entire range in the axis L direction on the rib side facing surface 51. The cross section of the protrusion 54 has a semicircular shape protruding toward the inside in the radial direction. On the rib-side facing surface 51, arc surfaces 55 and 56 that are defined around the axis L are provided on both sides of the protrusion 54 in the circumferential direction.

  The valve-body-side facing surface 52 is a region facing the rib-side facing surface 51 on the outer peripheral surface 3a of the valve body 3 (cylindrical plate portion 31 of the valve portion 27). The valve-body-side facing surface 52 is an arc surface that is defined with the axis L as the center. Therefore, the arcuate surfaces 55 and 56 of the valve element side facing surface 52 and the rib side facing surface 51 face each other with a certain gap therebetween.

  Here, the tip of the protrusion 54 on the rib side facing surface 51 is a contact portion 54 a that can contact the valve body facing surface 52. As shown in FIG. 4, in the cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the contact portion 54 a contacts the valve body side facing surface 52 at a point. The portion of the rib side facing surface 51 excluding the contact portion 54a is a relief portion that retreats from the contact portion 54a to the outer peripheral side. The escape portion is separated from the valve body side facing surface 52. That is, a gap is formed between the escape portion and the valve body side facing surface 52.

(Installation of check valve in water pipe)
As shown in FIG. 2, the check valve 1 includes a flange 5 between a primary side pipe 60 (upstream side pipe) and a secondary side pipe 61 (downstream side pipe) constituting a water pipe, and a valve box 2 Installed in the pipes 60 and 61. In the installation posture in which the check valve 1 is installed in the pipes 60 and 61, the axis L is coaxial with the primary side pipe and the secondary side pipe 61, and is along the flowing water direction S. Further, the bottom portion 13 of the valve box 2 is located downstream of the valve seat portion 12 in the flowing water direction S.

  Here, when the check valve 1 is installed, the primary side pipe 60 and the secondary side pipe 61 are fastened by a cap nut 62 that is screwed to the outer peripheral side of these connecting portions. When the cap nut 62 is tightened and the primary side pipe 60 and the secondary side pipe 61 approach each other, the rubber packing 8 is elastically deformed, and between the check valve 1 and the primary side pipe 60 and the check valve 1. And the secondary pipe 61 are sealed in a liquid-tight manner.

  The valve body 3 of the check valve 1 moves from the closed position 3 </ b> A to the open position 3 </ b> B against the urging force of the coil spring 4 due to the pressure of water flowing in through the inlet 11. As shown in FIG. 2B, when the valve body 3 moves to the open position 3 </ b> B, the water flowing in from the inflow port 11 flows out from the outflow port 15. When the inflow of water stops, as shown in FIG. 2A, the valve body 3 returns to the closed position 3 </ b> A by the biasing force of the coil spring 4 and closes the liquid inlet 11. Therefore, back flow of water is prevented.

  In very rare cases, foreign matter such as chips and sand from the pipe may enter the pipe. Here, as in this example, in the check valve 1 in which the valve box 2 is inserted into the pipe, the inlet 11 is smaller than the inner diameter of the pipes 60 and 61, so that water passes through the inlet 11. When doing so, the flow rate increases. Therefore, when the foreign matter that has entered the pipe 60 flows into the valve box 2 from the inlet 11, the foreign matter is formed on the outer peripheral surface 3a of the valve body 3 and the inner peripheral surface of the valve box 2 (the inner peripheral surface of the rib 14). There is a case where it enters between them and is sandwiched between them (a state where the check valve 1 bites foreign matter). When the check valve 1 bites foreign matter, the movement of the valve body 3 is inhibited. As a result, the check valve 1 has problems such as a decrease in the function of preventing the back flow of water and a decrease in the water flow rate.

On the other hand, in this example, the valve body side facing surface 52 of the valve body 3 and the rib side facing surface 51 of the rib 14 for guiding the valve body 3 are partly provided on the rib side facing surface 51. 54a contacts the valve body side facing surface 52. Therefore, the contact area between the valve body 3 and the rib 14 is smaller than when the entire valve body facing surface 52 and the entire rib side facing surface 51 are in contact with each other and the rib 14 guides the valve body 3. Therefore, it can suppress that a foreign material is pinched | interposed between the valve body 3 and the rib 14. FIG.

  Even when foreign matter is sandwiched between the valve body 3 and the rib 14, the contact area between the valve body 3 and the rib 14 is small and the contact portion 54a extends in the moving direction of the valve body 3. It is not stable between the valve body 3 and the rib 14. Accordingly, the foreign matter flows out between the valve body 3 and the rib 14 to the downstream side of the check valve 1 through the escape portion and the outlet 15. Therefore, it can prevent or suppress that check valve 1 will be in the state where a foreign object has been bitten. Furthermore, since the contact part 54a is extended in the moving direction of the valve body 3, the valve body 3 can be guided by the contact part 54a. Therefore, the behavior of the valve body 3 that moves between the closed position 3A and the open position 3B is stabilized.

  In this example, in the cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the contact portion 54a of the rib side facing surface 51 contacts the valve body facing surface 52 at a point. Thereby, since the contact area of the valve body 3 and the rib 14 becomes very small, it can suppress more that the non-return valve 1 bites in a foreign material. Moreover, it can suppress more that the non-return valve 1 will be in the state which has bitten the foreign material.

  Further, in this example, the contact portion 54 a and the relief portion are provided on the rib side facing surface 51. Therefore, even when the valve body 3 that moves between the closed position 3A and the open position 3B rotates in the circumferential direction, the contact area between the valve body 3 and the rib 14 can be kept small.

(Verification experiment)
Here, the present inventors conducted a verification experiment for verifying biting of foreign matter in the check valve 1. FIG. 5A is an explanatory diagram of an experimental apparatus for a verification experiment, and FIG. 5B is a cross-sectional view of a check valve of a reference example as a comparison target of the check valve 1 of this example. FIG. 6 is a table showing experimental results of the verification experiment.

  As shown in FIG. 5 (a), the experimental apparatus 100 includes a pressure source 102, a flow meter 103, a shut-off valve 104, a foreign material input port 105, and a pressure gauge 106 from an upstream side in the flowing water direction S to the experimental pipe 101. The specimens (check valve 1, check valve 1 ′), flow rate adjustment valve 107, and stop valve 108 are arranged in this order.

  As shown in FIG. 5B, the check valve 1 ′ of the reference example has a configuration in which the entire valve body side facing surface 52 and the entire rib side facing surface 51 can contact each other. More specifically, the check valve 1 ′ does not include the protrusion 54 on the rib side facing surface 51, and the entire surface is an arc surface defined with the axis L as the center. The check valve 1 ′ of the reference example is the same as the above example except for the shape of the rib-side facing surface 51, and thus the description of the other structure is omitted.

  In the verification experiment, 0.1 g of sand is put through the foreign material inlet 105 and water is passed for 2 minutes. In the meantime, the closing valve 108 is opened and closed every 30 seconds to check the sand bite in the check valves 1 and 1 ′. In the verification experiment, the hydrostatic pressure was set to 0.2 MPa. The flow rate was 8 L / min and 16 L / min. The size of the sand particles was 0.25 mm and 0.5 mm. As the check valve 1 and the check valve 1 ′, five pieces were used as specimens, respectively.

  As shown in FIG. 6, in the check valve 1 of this example, the check valve 1 did not bite sand. On the other hand, in the check valve 1 ′ of the reference example, sand was bitten with a probability of 40% to 100%. Therefore, according to the check valve 1 of this example, it is possible to prevent the foreign matter from being caught. Here, the pressure loss when the check valve 1 of this example was used was 15.7 kPa, which was the same as the pressure loss of 15.7 kPa when the check valve 1 ′ of the reference example was used.

(Modification 1)
Next, a check valve according to a modification will be described with reference to FIGS. FIGS. 7A and 7B are explanatory diagrams of check valves of modified examples 1 and 2 in which the shape of the rib-side facing surface 51 is different from the above example. 7A and 7B are cross-sectional views of the check valves of the first and second modified examples, and the lower diagram is an experiment of a verification experiment by the experimental apparatus 100 shown in FIG. 5A. It is a table | surface which shows a result. The check valves of the first and second modifications are the same as those in the above example except for the shape of the rib-side facing surface 51. Therefore, the rib-side facing surface 51 is described, and the description of the other configurations is omitted. To do.

  As shown to Fig.7 (a), the rib side opposing surface 51 of 1 A of check valves of the modification 1 is the V shape which the cross-sectional shape protrudes to an inner peripheral side. Specifically, the rib-side facing surface 51 includes a first inclined surface 71 that is inclined inwardly (in a direction approaching the valve body 3) from one circumferential edge toward the center, and the other circumferential edge. A second inclined surface 72 that is inclined inwardly (in a direction approaching the valve body 3) from the edge toward the center is provided. Therefore, the rib side facing surface 51 includes a ridge line extending in the direction of the axis L at the center in the circumferential direction. Here, the ridge line of the rib side facing surface 51 is a contact portion 73 that can contact the valve body facing surface 52. In the cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the contact portion 73 contacts the valve body side facing surface 52 at a point. A portion of the rib side facing surface 51 excluding the contact portion 73 is an escape portion that retreats from the contact portion 73 and is separated from the valve element side facing surface 52. That is, a gap is formed between the escape portion and the valve body side facing surface 52.

  In the check valve 1A of the first modification, the probability of biting sand decreased when the flow rate was 8 L / mm and the size of the sand particles was 0.25 mm, as compared with the check valve 1 'of the reference example. Further, in the check valve 1 </ b> A of this example, it is possible to suppress wear of the rib side facing surface 51 as compared with the check valve 1 described above.

(Modification 2)
As illustrated in FIG. 7B, the check valve 1 </ b> B of the second modification includes a groove 75 extending in the axis L direction at the center portion in the circumferential direction of the rib side facing surface 51. In this example, the cross-sectional shape of the groove 75 is V-shaped. More specifically, the rib-side facing surface 51 includes a first inclined surface 76 that is inclined outward (in a direction away from the valve body 3) from one circumferential edge to the center, and the other circumferential edge. And a second inclined surface 77 that is inclined outward (in a direction away from the valve body 3) from the end edge toward the center.

  Here, the edge part of the both sides of the circumferential direction of the rib side opposing surface 51 is the contact parts 78 and 79 which can contact the valve body opposing surface 52. FIG. In the cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the two contact portions 78 and 79 are in contact with the valve body-side facing surface 52 at points. A portion of the rib side facing surface 51 excluding the contact portions 78 and 79 is an escape portion that retreats from the contact portion 73 and is separated from the valve element side facing surface 52. That is, a gap is formed between the escape portion and the valve body side facing surface 52.

  In the check valve 1B of the modified example 2, compared to the check valve 1 ′ of the reference example, when the sand particle size is 0.25 mm at a flow rate of 8 L / mm, and the sand particles at a flow rate of 16 L / mm In the case of a size of 0.25 mm, the probability of biting sand decreased. In this example, since the valve body 3 is guided by the plurality of contact portions 78 and 79, the behavior of the valve body 3 that moves between the closed position 3A and the open position 3B is likely to be stable.

  In the above example, the contact portion provided on the rib-side facing surface 51 is in contact with the valve-body facing surface 52 at a point in the cross section obtained by cutting the rib 14 and the valve body 3 in the direction orthogonal to the axis L. However, contact may be made on the surface.

(Modification 3)
In the above example, the rib 54 and the groove 75 are provided on the rib side facing surface 51, but the valve body side facing surface 5
You may provide a protrusion and a groove | channel on the 2 side. FIGS. 8A, 8B, and 8C are explanatory views of check valves of modified examples 3, 4, and 5 in which the shapes of the rib side facing surface 51 and the valve body facing surface 52 are different from the above examples, respectively. It is. In FIG. 8, sectional drawing of the check valve of each modification 3, 4, and 5 is shown. In the third, fourth, and fifth modifications, the rib side facing surface 51 and the valve body side facing surface are the same as the check valve 1 except for the configuration of the rib side facing surface 51 and the shape of the valve body facing surface 52. 52 will be described, and description of other components will be omitted.

  As shown in FIG. 8A, the check valve 1 </ b> C of the third modification includes an arc surface defined around the axis L as the rib side facing surface 51. The valve-body-side facing surface 52 includes a protrusion 81 that extends in the axis L direction at a central portion in the circumferential direction. The cross section of the protrusion 81 has a semicircular shape protruding in the radial direction toward the outer peripheral side. On the valve-body-side facing surface 52, arc surfaces 82 and 83 defined with the axis L as the center are provided on both sides of the protrusion 81 in the circumferential direction.

  Here, the tip of the protrusion 81 of the valve element facing surface 52 is a contact portion 81 a that can contact the rib facing surface 51. The contact portion 81a contacts the rib side facing surface 51 at a point in a cross section obtained by cutting the rib 14 and the valve body 3 along a plane orthogonal to the axis L. A portion excluding the contact portion 81 a in the valve body side facing surface 52 is an escape portion that retreats from the contact portion 81 a and is separated from the rib side facing surface 51. That is, a gap is formed between the escape portion and the rib side facing surface 51.

  Also in the check valve 1 </ b> C of this example, it is possible to prevent foreign matter from being sandwiched between the valve body 3 and the rib 14, as in the above example. Moreover, it can prevent or suppress that the non-return valve 1 will be in the state which has bitten the foreign material. Furthermore, since the valve body 3 can be guided by the contact portion 81a, the behavior of the valve body 3 moving between the closed position 3A and the open position 3B is stabilized. Note that the contact portion 81a and the rib-side facing surface 51 may come into contact with each other in a cross section obtained by cutting the rib 14 and the valve body 3 in a direction orthogonal to the axis L.

(Modification 4)
As shown in FIG. 8B, the check valve 1 </ b> D of the fourth modification includes an arc surface defined around the axis L as the rib side facing surface 51. The valve-body-side facing surface 52 includes a single groove 85 that extends in the axis L direction at the central portion in the circumferential direction. In this example, the cross-sectional shape of the groove 85 is V-shaped. More specifically, the valve-body-side facing surface 52 includes a first inclined surface 86 that is inclined inward (a direction away from the ribs 14) from one circumferential edge toward the center, and the other circumferential edge. A second inclined surface 87 is provided that is inclined inwardly (in a direction away from the ribs 14) from the edge toward the center.

  Here, edge portions on both sides in the circumferential direction of the valve-body-side facing surface 52 are contact portions 88 and 89 that can contact the rib-side facing surface 51. In the cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the two contact portions 88 and 89 are in contact with the rib-side facing surface 51 at a point or a slight surface, respectively. A portion excluding the contact portions 88 and 89 in the valve body side facing surface 52 is a relief portion that retreats from the contact portions 88 and 89 and is separated from the valve body side facing surface 52. That is, a gap is formed between the escape portion and the rib side facing surface 51.

  Also in the check valve 1D of this example, it is possible to suppress foreign matter from being sandwiched between the valve body 3 and the rib 14 as in the above example. Moreover, it can prevent or suppress that the non-return valve 1 will be in the state which has bitten the foreign material. Furthermore, since the valve body 3 can be guided by the contact portion 81a, the behavior of the valve body 3 moving between the closed position 3A and the open position 3B is stabilized. Moreover, in this example, since the valve body 3 is guided by the plurality of contact portions 88 and 89, the behavior of the valve body 3 is easily stabilized.

(Modification 5)
As shown in FIG. 8C, the check valve 1 </ b> E according to the modified example 5 includes a circular arc surface defined around the axis L as the rib side facing surface 51. The valve-body-side facing surface 52 includes three grooves 91 extending in parallel with the axis L direction. The cross-sectional shape of each groove 91 is semicircular.

  Here, between the grooves 91 in the circumferential direction of the valve-body-side facing surface 52, contact portions 92 and 93 that can contact the rib-side facing surface 51. In a cross section in which the rib 14 and the valve body 3 are cut in a direction orthogonal to the axis L, the contact portions 92 and 93 between the grooves 91 are in contact with the rib-side facing surface 51 at points. Moreover, the edge part of the both sides of the circumferential direction of the valve body side opposing surface 52 is the contact parts 94 and 95 which can contact the rib side opposing surface 51. As shown in FIG. The contact portions 92 and 93 are in contact with the rib-side facing surface 51 at a point or a slight surface. A portion excluding the contact portions 92 to 95 in the valve body side facing surface 52 is a relief portion that retreats from the contact portions 92 and 93 and is separated from the valve body side facing surface 52. That is, a gap is formed between the escape portion and the rib side facing surface 51.

  Also in the check valve 1E of this example, it is possible to prevent foreign matter from being sandwiched between the valve body 3 and the rib 14 as in the above example. Moreover, it can prevent or suppress that the non-return valve 1 will be in the state which has bitten the foreign material. Furthermore, since the valve body 3 can be guided by the contact portions 92 to 95, the behavior of the valve body 3 that moves between the closed position 3A and the open position 3B is stabilized. Moreover, in this example, since the valve body 3 is guided by the some contact parts 92-95, the behavior of the valve body 3 is easy to be stabilized.

1 · 1A to 1E ··· Check valve 3 ··· Valve element 3A ··· Closed position 3B ··· Open position 11 ··· Inlet (liquid inlet)
12 ... valve seat part 14 ... rib 15 ... outlet (liquid outlet)
51 ... Rib-side facing surface 52 ... Valve-side facing surface 54a, 73, 78, 79, 81a, 88, 89, 92 to 95 ... Contact portion L ... Axial direction (moving direction)

Claims (8)

A valve box with an annular valve seat with a liquid inlet;
A valve body movable between a closed position in contact with the valve seat portion to close the liquid inlet, and an open position separated from the valve seat portion;
A flange projecting outward from the valve seat portion,
The valve box is
A plurality of ribs extending in the moving direction of the valve body from the valve seat portion to guide the valve body at a position surrounding the valve body from the outer peripheral side;
A liquid outlet provided between the ribs in the circumferential direction and opening radially outward of the ribs ;
One opposing surface of the rib-side facing surface that is a region facing the rib-side facing surface in the outer peripheral surface of the valve body and the surface facing the rib-side facing surface in each rib is the other facing surface A contact portion that can be contacted, and a relief portion that is spaced from the other facing surface in a direction orthogonal to the moving direction of the valve body ,
The check portion is characterized in that the contact portion extends in the moving direction. In claim 1,
In the cross section obtained by cutting the rib and the valve body in a direction orthogonal to the moving direction, the check portion of the one facing surface is in contact with the other facing surface at a point. In claim 1 or 2,
The check valve according to claim 1, wherein the one opposing surface includes the contact portion at a center in the circumferential direction. In claim 1 or 2,
Each of said one opposing surfaces is equipped with the said some contact part, The check valve characterized by the above-mentioned . In claim 4 ,
The one facing surface is provided with a groove extending in the moving direction,
The check valve according to claim 1, wherein the contact portion is an edge on both sides in the circumferential direction of the one facing surface . In any one of claims 1 to 3 ,
The one opposing surface is provided with a ridge extending in the moving direction,
The check valve is characterized in that the contact portion is a tip of the protrusion . In any one of claims 1 to 6,
The check valve, wherein the contact portion and the relief portion are provided on the rib side facing surface. In any one of claims 1 to 3,
The check valve according to claim 1, wherein the contact portion and the escape portion are provided on the valve body side facing surface.

Images