JP2010112405A - Check valve - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a check valve which prevents an abrupt increase of the flow speed of a fluid when the fluid flows into a penetration hole of a valve plate, and reduces a pressure loss of the fluid. <P>SOLUTION: The check valve is characterized in that: a plurality of fluid lead-in holes 2b penetrating a valve seat are formed at the valve seat (sheet 2); a plurality of fluid lead-out holes 3c penetrating a valve guide are formed at the valve guide (guide 3); the fluid lead-in holes 2b and the fluid lead-out holes 3c are arranged in positions displaced from each other when viewed from the normal direction of the valve plate (plate 4); a plurality of penetration holes 4a penetrating the valve plate are formed in the valve plate in a position which is not overlapped with the fluid lead-in holes 2b, but overlapped with the fluid lead-out holes 3c when viewed from the normal direction of the valve plate; each of the fluid lead-in holes 2b has a valve-plate side passage (plate-side passage 22) formed at the valve-plate side, and an expanded passage 21 formed at an opposite side with respect to the valve plate; a cross section area parallel with the valve plate of the expanded passage 21 is expanded larger than a cross section area parallel with the valve plate of the valve-plate side passage; and the inner wall 21a of the expanded passage 21 is formed to be parallel with the normal direction of the valve plate. <P>COPYRIGHT: (C)2010,JPO&INPIT

Description

  The present invention relates to a check valve.

2. Description of the Related Art Conventionally, check valves are known that are provided at suction and discharge ports of a reciprocating compressor and are used as suction and discharge valves of the reciprocating compressor. This check valve is provided with a valve plate in the gap between the valve seat and the valve seat, allows the fluid flowing in from the valve seat side to pass, and blocks the fluid flowing in from the valve seat side by the valve plate ( For example, see Patent Document 1).
Japanese Patent Laid-Open No. 2002-81380

However, the above-described conventional check valve has a problem that the flow velocity of the fluid passing through the through hole formed in the valve plate increases rapidly and the pressure loss of the fluid increases.
5 and 6 are cross-sectional views along the normal direction of the valve plate of the conventional check valve, and are enlarged cross-sectional views in which the vicinity of the through hole of the valve plate is enlarged. In FIG. 6A, the flow velocity of the fluid is represented by a vector, and in FIG. 6B, the pressure in the vicinity of the inlet of the through hole is represented by an isobaric line. Moreover, in FIG.6 (b), a pressure is so low that it is a darker color inside an isobar.

  As shown in FIG. 5, in the conventional check valve 100, a plurality of fluid introduction holes 20 b are formed in the valve seat 20. The fluid introduction hole 20b is provided on the valve plate side flow path 220 formed on the valve plate 40 side and on the opposite side of the valve plate 40, and a cross-sectional area perpendicular to the normal line of the valve plate 40 has a valve plate side flow path 220. And an expanded flow path 210 that is larger than that. In the conventional check valve 100, the inner wall 210a of the expansion flow path 210 is formed in a taper shape for the purpose of preventing a rapid change in the cross-sectional area of the fluid introduction hole 20b and reducing pressure loss. Thereby, the cross-sectional area perpendicular to the normal line of the valve plate 40 of the expansion channel 210 gradually decreases as the valve plate side channel 220 is approached.

In the conventional check valve 100, the valve plate 40 is pushed down in the direction of the valve receiver 30 by the fluid F flowing from the opening end of the fluid introduction hole 20 b of the valve seat 20 on the expansion flow path 210 side. The fluid F that flows between the pressed valve plate 40 and the valve seat 20 flows into the through hole 40a of the valve plate 40 and flows out from the fluid outlet hole 30c of the valve receiver 30 to the outside.
At this time, there is almost no change in the velocity of the fluid F in the expansion flow path 210, but as shown in FIG. 6A, the cross-sectional area is smaller than that of the expansion flow path 210 and the fluid F is contracted. In the plate side flow path 220, the flow velocity of the fluid F increases rapidly. Thereby, as shown in FIG.6 (b), the big pressure loss will generate | occur | produce in the fluid F in the vicinity of the opening end 40f of the through-hole 40a.

  Accordingly, the present invention provides a check valve that can prevent the fluid flow velocity from rapidly increasing when the fluid flows into the through hole of the valve plate and reduce the pressure loss of the fluid. It is.

  In order to solve the above-described problems, the check valve of the present invention includes a valve plate in a gap between the valve seat and the valve receiver, and fluid that flows in the normal direction of the valve plate from the valve seat side. A non-return valve that allows the valve plate to block the fluid flowing in the normal direction from the valve receiving side, and the valve seat includes a plurality of valves that pass through the valve seat in the normal direction. A fluid introduction hole is formed, and the valve receiver has a plurality of fluid outlet holes penetrating the valve receiver in the normal direction, and the fluid introduction hole and the fluid outlet hole are formed from the normal direction. The valve plate is placed at a position that overlaps the fluid lead-out hole but not the fluid introduction hole when viewed from the normal direction. A plurality of through-holes are formed, and the fluid introduction hole includes a valve plate-side flow path provided on the valve plate side, An expansion channel provided on the opposite side of the plate, and a cross-sectional area of the expansion channel parallel to the valve plate is larger than a cross-sectional area of the valve plate side channel parallel to the valve plate And the inner wall of the said expansion flow path is provided in parallel with the said normal line direction, It is characterized by the above-mentioned.

  With this configuration, the fluid that has flowed into the fluid introduction hole of the valve seat from the upstream side of the valve flows down between the valve plate and the valve seat by pushing down the valve plate in the valve receiving direction. The fluid that has passed between the valve plate and the valve seat flows into the through hole of the valve plate. At this time, the inner wall of the expansion channel is provided in parallel to the normal direction of the valve plate, and the cross-sectional area in the direction parallel to the valve plate of the expansion channel is constant from the upstream side to the downstream side of the fluid. . Therefore, the cross-sectional area of the expansion channel can be increased as compared with the conventional case where the inner wall of the expansion channel is formed in a tapered shape. Therefore, it is possible to prevent an increase in the flow rate of the fluid flowing through the expansion channel. Thereby, when the fluid flows into the through hole of the valve plate, it is possible to prevent the fluid flow rate from rapidly increasing. Therefore, according to the check valve of the present invention, the pressure loss of the fluid flowing through the check valve can be reduced.

  Further, in the check valve according to the present invention, the valve seat is formed with a valve seat surface that contacts the periphery of the opening end of the valve plate on the valve seat side and blocks the fluid flow. The valve seat surface is provided so that the open end of the valve plate is in contact with the valve seat surface when the fluid is shut off.

  With this configuration, when the through hole of the valve plate and the fluid outlet hole of the valve receiver are formed with the same dimensions as the conventional one, the distance between the valve plate side flow paths of the fluid introduction hole of the valve seat is conventionally changed. The cross-sectional area in the direction parallel to the valve plate of the valve plate side flow path can be increased. Therefore, it is possible to prevent an increase in the flow rate of the fluid flowing through the valve plate side flow path. Thereby, when the fluid flows into the through hole of the valve plate, it is possible to more effectively prevent the fluid flow velocity from rapidly increasing.

  Further, in the check valve of the present invention, a step is formed in a direction parallel to the valve plate between the inner wall of the expansion channel and the inner wall of the valve plate side channel, and the height of the step is The sealing width is substantially equal to a sealing width which is a distance between the outer edge of the valve seat surface and the opening end of the valve plate in a direction parallel to the valve plate.

  By configuring in this way, the cross-sectional area of the expansion flow path of the fluid introduction hole of the valve seat is increased from the cross-sectional area of the valve plate side flow path while ensuring a sufficient sealing width for sealing the fluid. It becomes possible to make it. Moreover, the space | interval of the expansion flow paths of a some fluid introduction hole can be narrowed, and the cross-sectional area of an expansion flow path can be increased, ensuring the strength of a valve seat.

  The check valve according to the present invention is characterized in that an inner wall of the valve plate side channel is provided in parallel to the normal direction.

  By comprising in this way, the cross-sectional area of the direction parallel to a valve plate from the edge part on the opposite side of the valve plate of a valve plate side flow path to the edge part on the valve plate side can be made constant. Thereby, it can prevent that the flow velocity of the fluid which distribute | circulates the valve-plate side flow path increases.

  The check valve according to the present invention is characterized in that the dimension of the expansion channel in the normal direction is four times or more the dimension of the valve plate side channel in the normal direction.

  By configuring in this way, it is possible to sufficiently secure the dimension of the expansion flow path in the normal direction of the valve plate and prevent an increase in the flow velocity of the fluid flowing through the fluid introduction hole.

  The check valve according to the present invention is characterized in that a concave curved surface portion is formed between an inner wall of the expansion channel and an inner wall of the valve plate side channel.

  By comprising in this way, the expansion flow path and valve-plate side flow path from which cross-sectional areas differ can be connected smoothly, and the pressure loss of the fluid which distribute | circulates a fluid introduction hole can be reduced.

  The check valve of the present invention is characterized in that the opening end of the fluid introduction hole on the valve plate side is chamfered.

  By comprising in this way, the flow of the fluid which flows into the through-hole of a valve plate from the fluid introduction hole of a valve seat can be made more linear, and the pressure loss of a fluid can be reduced.

  In the check valve of the present invention, the inner wall of the fluid lead-out hole of the valve receiver extends in the normal direction so that a cross-sectional area perpendicular to the normal direction increases as the distance from the valve plate increases. It is provided with an inclination with respect to it.

  With this configuration, the cross-sectional area of the fluid outlet hole in the direction parallel to the valve plate can be increased, and the pressure loss of the fluid flowing through the fluid outlet hole can be reduced.

  According to the check valve of the present invention, when the fluid flows into the through hole of the valve plate, the flow velocity of the fluid can be prevented from increasing rapidly, and the pressure loss of the fluid can be reduced.

  Hereinafter, embodiments of the present invention will be described with reference to the drawings. In the following drawings, the scale is appropriately changed for each member so that each member has a size that can be recognized on the drawing.

FIG. 1 is a perspective view of the check valve 1 of the present embodiment, and FIG. 2 is a partial cross-sectional view of the check valve 1 shown in FIG. The check valve 1 of the present embodiment is provided, for example, at a suction port and a discharge port of a reciprocating compressor that compresses BOG (Boil Off Gas) generated by heat input to LNG (Liquefied Natural Gas). It is used as a valve and a discharge valve.
As shown in FIGS. 1 and 2, the check valve 1 includes a seat (valve seat) 2 disposed on the upstream side of the fluid F and a guide (valve receiver) 3 disposed on the downstream side of the fluid F. I have. The sheet 2 and the guide 3 are formed in a substantially cylindrical shape having substantially the same diameter, and are arranged so as to overlap with the inflow direction of the fluid F (the arrow direction in the figure).

  As shown in FIG. 2, the outer peripheral portion 2 a of the surface of the sheet 2 on the guide 3 side is in close contact with the outer peripheral portion 3 a of the surface of the guide 3 on the sheet 2 side. A recess 3 b is formed on the surface of the guide 3 on the sheet 2 side, and a gap S is formed between the sheet 2 and the guide 3. A disc-shaped plate (valve plate) 4 is accommodated in the recess 3 b, and the plate 4 is disposed in the gap S between the seat 2 and the guide 3.

  As shown in FIGS. 1 and 2, a plurality of fluid introduction holes 2 b that penetrate the sheet 2 in the normal H direction of the plate 4 are formed in the sheet 2. The fluid introduction holes 2b have a circular arrangement in which a plurality of fluid introduction holes 2b are arranged on the same circumference when viewed from the normal H direction of the plate 4, and a plurality of circular arrangements having different diameters are concentric. Is arranged. Further, the fluid introduction hole 2b has a long hole shape extending in the circumferential direction of each circular arrangement.

  As shown in FIG. 2, a plurality of fluid outlet holes 3 c are formed in the guide 3. The fluid outlet hole 3 c is provided so as to penetrate the guide 3 in the normal H direction of the plate 4. The fluid lead-out holes 3 c of the guide 3 and the fluid introduction holes 2 b of the sheet 2 are alternately formed in the surface direction of the plate 4, and are arranged at positions shifted from the normal line H direction of the plate 4. That is, the fluid outlet hole 3 c of the guide 3 and the fluid inlet hole 2 b of the sheet 2 do not overlap each other when viewed from the normal line H direction of the plate 4.

  The fluid outlet hole 3c of the guide 3 is a circle in which a plurality of fluid outlet holes 3c are arranged on the same circumference as seen from the normal line H direction of the plate 4 in the same manner as the fluid inlet hole 2b of the sheet 2 shown in FIG. A plurality of circular arrays having different diameters are arranged concentrically. Further, the fluid outlet hole 3c of the guide 3 has a long hole-like shape extending in the circumferential direction of each circular arrangement, like the fluid introduction hole 2b of the sheet 2 shown in FIG.

  As shown in FIG. 2, the plate 4 has a plurality of positions that do not overlap with the fluid introduction hole 2 b of the sheet 2 but overlap with the fluid outlet hole 3 c of the guide 3 when viewed from the normal H direction of the plate 4. A through hole 4a is formed. The through hole 4 a is provided so as to penetrate the plate 4 in the normal H direction of the plate 4. In addition, a round bar-shaped spindle 5 is provided so as to pass through the central portion of the sheet 2, the guide 3, and the plate 4 in the normal line H direction of the plate 4, and the plate 4 is fixed to the spindle 5.

  A male screw portion 5 a is formed at the proximal end portion of the spindle 5 on the guide 3 side. A male screw part 5 a at the base end of the spindle 5 is screwed into a female screw part 3 d provided at the center of the guide 3 and fixed to the guide 3. The spindle 5 is provided such that a tip portion opposite to the base end portion where the male screw portion 5a is formed protrudes to the upstream side of the fluid F.

  A male screw portion 5 b is formed on the upstream side of the fluid F with respect to the sheet 2 at the center of the spindle 5. A nut 6 is screwed into the male screw portion 5 b at the center of the spindle 5, and a washer 7 is inserted between the nut 6 and the seat 2. Thereby, the sheet 2 and the guide 3 are integrally fixed, and a pressing force is applied between the outer peripheral portion 2a of the surface of the sheet 2 on the guide 3 side and the outer peripheral portion 3a of the surface of the guide 3 on the sheet 2 side. Has been.

  A spring portion (not shown) is provided around the central portion of the plate 4 fixed to the spindle 5. The spring part is formed in an arcuate band shape by forming arcuate cutouts on the outside and inside of the spring part. Thereby, the spring part connects a part of center part of the plate 4 and a part of outer peripheral part. The spring portion is elastically deformed when a predetermined force is applied in the normal line H direction of the plate 4 so that the outer peripheral portion of the plate 4 in which the through hole 4 a is formed moves in the normal line H direction of the plate 4. Further, a predetermined elastic modulus is set.

  Similar to the fluid introduction hole 2b of the sheet 2 shown in FIG. 1, the through-hole 4a of the plate 4 is a circular shape in which a plurality of through-holes 4a are arranged on the same circumference when viewed from the normal line H direction of the plate 4. A plurality of circular arrays having different diameters are arranged concentrically. Further, the through holes 4 a of the plate 4 have a long hole shape extending in the circumferential direction of a circular arrangement, like the fluid introduction holes 2 b of the sheet 2 and the fluid outlet holes 3 c of the guide 3.

FIG. 3 is an enlarged cross-sectional view of a main part of the check valve 1 shown in FIGS. 1 and 2.
As shown in FIG. 3, the fluid introduction hole 2 b of the sheet 2 is provided on the side opposite to the plate 4 on the upstream side of the fluid F and on the plate 4 side on the downstream side of the fluid F. Plate-side flow path (valve plate-side flow path) 22. The inner wall 21a of the expansion channel 21 and the inner wall 22a of the plate-side channel 22 are provided substantially parallel to the normal line H along the normal line H direction of the plate 4 (see FIG. 2). The cross-sectional area of the extension flow path 21 in the direction parallel to the plate 4 is larger than the cross-sectional area of the plate-side flow path 22 in the direction parallel to the plate 4. As a result, a step G is formed between the inner wall 21 a of the expansion channel 21 and the inner wall 22 a of the plate-side channel 22 in a direction parallel to the plate 4.

A concave curved surface portion 23 is formed in the step G between the inner wall 21a of the expansion flow path 21 and the inner wall 22a of the plate side flow path 22, and the inner wall 21a of the expansion flow path 21 and the inner wall 22a of the plate side flow path 22 are Are smoothly connected in the flow direction of the fluid F (arrow direction in the figure).
Further, in the vicinity of the inlet of the fluid F of the expansion channel 21, that is, in the vicinity of the opening end of the fluid introduction hole 2b opposite to the plate 4, a substantially arc-shaped fluid introduction surface 21r is formed in a sectional view shown in FIG. The open end is larger than the expansion flow path 21.
The dimension L1 of the expansion channel 21 in the normal H direction of the plate 4 is formed to be larger than the dimension L2 of the plate-side channel 22 in the same direction. The dimension L1 of the expansion channel 21 is, for example, about four times or more the dimension L2 of the plate-side channel 22.

  The seat 2 is formed with a valve seat surface 2s that contacts the periphery of the opening end 4f on the seat 2 side of the through hole 4a of the plate 4 and blocks the flow of the fluid F. The valve seat surface 2s is provided such that when the fluid F is shut off, the opening end 4f of the plate 4 on the seat 2 side comes into contact with the valve seat surface 2s. The outer periphery of the valve seat surface 2s, that is, the opening end of the fluid introduction hole 2b on the plate 4 side is chamfered, and a tapered surface 2t inclined by about 45 ° with respect to the normal line H direction of the plate 4 is formed. When the valve seat surface 2s comes into contact with the plate 4, the width in the direction parallel to the plate 4 where the valve seat surface 2s contacts the plate 4 is a so-called sealing width (sealing) for sealing the fluid F. Stop) W.

  The sealing width W is equal to the distance between the outer edge 2 e of the valve seat surface 2 s and the edge of the opening end 4 f of the seat 2 in the direction parallel to the plate 4. Further, the sealing width W is substantially equal to the height h in the direction parallel to the plate 4 of the step G between the inner wall 21 a of the expansion flow channel 21 and the inner wall 22 a of the plate-side flow channel 22. The height h of the step G is determined by the dimension of the through hole 4a of the plate 4, the pressure of the fluid F, etc., in addition to the sealing width W.

  Further, the inner wall 3 e of the fluid outlet hole 3 c of the valve receiver 3 is provided in a tapered shape so as to be inclined with respect to the normal line H direction of the plate 4. Thereby, the cross-sectional area perpendicular to the normal line H direction of the plate 4 of the fluid outlet hole 3 c increases as the distance from the plate 4 increases. Further, in the vicinity of the outlet of the fluid F in the fluid outlet hole 3c, that is, in the vicinity of the opening end on the side opposite to the plate 4, the cross section shown in FIG. A substantially arc-shaped fluid outlet surface 3r is formed as viewed, and the opening end is enlarged.

Next, the operation of this embodiment will be described with reference to FIG.
4 is an enlarged cross-sectional view of the main part of the check valve, where (a) shows the flow of the fluid F from the seat 2 side to the guide 3 side, and (b) shows the through hole 4a of the plate 4 on the seat 2 side. The pressure distribution of the fluid F in the vicinity of the inlet of the open end 4f is shown. In FIG. 4A, the flow velocity of the fluid F is schematically represented by a vector. Moreover, in FIG.4 (b), the pressure of the vicinity of the opening end 4f of the through-hole 4a is represented by the isobaric line. Moreover, in FIG.4 (b), a pressure is so low that it is a darker color inside an isobar.

  For example, when the check valve 1 of the present embodiment is used as a discharge valve by being attached to a discharge port pipe of a reciprocating compressor (not shown), the seat 2 side of the check valve 1 shown in FIGS. It arrange | positions so that it may become a discharge outlet side (upstream side of the fluid F). Further, when used as a suction valve by being attached to a pipe of the suction port, the check valve 1 is arranged so that the guide 3 side is on the suction port side (downstream side of the fluid F).

  When the reciprocating compressor sucks the fluid F from the suction port, in the check valve 1 provided at the suction port of the reciprocating compressor, the fluid F on the guide 3 side connected to the suction port via a pipe. Becomes a lower pressure than the fluid F on the seat 2 side. Due to the pressure difference of the fluid F, a force in the direction of the guide 3 in the normal H direction of the plate 4 acts on the plate 4 of the check valve 1. Due to this force, the spring portion connecting the central portion and the peripheral portion of the plate 4 fixed to the spindle 5 is elastically deformed, and the outer peripheral portion of the plate 4 moves to the guide 3 side. Thereby, as shown in FIG. 3, the plate 4 moves to the guide 3 side. 4A, the fluid F that has flowed into the fluid introduction hole 2b of the sheet 2 passes through a flow path formed between the sheet 2 and the plate 4, and the guide 3 illustrated in FIG. Flows into the fluid outlet hole 3c. The fluid F flowing into the fluid outlet hole 3c of the guide 3 is discharged from the guide 3 side to the outside of the check valve 1 and flows into the suction port of the reciprocating compressor.

On the other hand, in the check valve 1 provided at the discharge port of the reciprocating compressor, the fluid F on the seat 2 side connected to the discharge port via a pipe has a lower pressure than the fluid F on the guide 3 side. Due to the pressure difference of the fluid F, a force in the direction of the seat 2 in the normal H direction of the plate 4 acts on the plate 4 of the check valve 1. By this force, the spring portion connecting the central portion and the peripheral portion of the plate 4 fixed to the spindle 5 is elastically deformed, and the outer peripheral portion of the plate 4 moves to the seat 2 side. As a result, the plate 4 moves to the sheet 2 side as shown in FIG. The surface of the plate 4 on the seat 2 side comes into contact with the valve seat surface 2 s of the seat 2. As a result, the fluid introduction hole 2b of the sheet 2 is closed, and the flow of the fluid F from the fluid outlet hole 3c of the guide 3 to the fluid introduction hole 2b of the sheet 2 is blocked.
In this way, by using the check valve 1 of the present embodiment for the suction port and the discharge port of the reciprocating compressor, when the fluid F is sucked by the reciprocating compressor, the fluid F flows into the discharge port. The fluid F can be sucked from the suction port by blocking.

  Further, when the fluid F compressed by the reciprocating compressor is discharged from the discharge port, the check valve 1 provided at the discharge port of the reciprocating compressor has a seat 2 connected to the discharge port via a pipe. The fluid F on the side becomes a higher pressure than the fluid F on the guide 3 side. Due to the pressure difference of the fluid F, a force in the direction of the guide 3 in the normal H direction of the plate 4 acts on the plate 4 of the check valve 1. Due to this force, the spring portion connecting the central portion and the peripheral portion of the plate 4 fixed to the spindle 5 is elastically deformed, and the outer peripheral portion of the plate 4 moves to the guide 3 side. Thereby, as shown in FIG. 3, the plate 4 moves to the guide 3 side. And the fluid F which flowed into the fluid introduction hole 2b of the sheet | seat 2 shows the guide 3 shown in FIG. 3 through the flow path formed between the sheet | seat 2 and the plate 4, as shown to Fig.4 (a). Flows into the fluid outlet hole 3c. The fluid F that has flowed into the fluid outlet hole 3 c of the guide 3 is discharged from the guide 3 side to the outside of the check valve 1.

On the other hand, in the check valve 1 provided at the suction port of the reciprocating compressor, the fluid F on the guide 3 side connected to the suction port via a pipe has a higher pressure than the fluid F on the seat 2 side. Due to the pressure difference of the fluid F, a force in the direction of the seat 2 in the normal H direction of the plate 4 acts on the plate 4 of the check valve 1. By this force, the spring portion connecting the central portion and the peripheral portion of the plate 4 fixed to the spindle 5 is elastically deformed, and the outer peripheral portion of the plate 4 moves to the seat 2 side. As a result, as shown in FIG. 4A, the plate 4 moves to the sheet 2 side. The surface of the plate 4 on the seat 2 side comes into contact with the valve seat surface 2 s of the seat 2. As a result, the fluid introduction hole 2b of the sheet 2 is closed, and the flow of the fluid F from the fluid outlet hole 3c of the guide 3 to the fluid introduction hole 2b of the sheet 2 is blocked.
Thus, by using the check valve 1 of the present embodiment for the suction port and the discharge port of the reciprocating compressor, when the fluid F is discharged by the reciprocating compressor, the fluid F flows out from the suction port. The fluid F can be discharged from the discharge port by blocking.

  Here, in the check valve 1 of the present embodiment, as shown in FIG. 3, the inner wall 21 a of the expansion channel 21 is provided in parallel to the normal H direction of the plate 4. The cross-sectional area of the expansion channel 21 in the direction parallel to the plate 4 is constant from the upstream side to the downstream side of the fluid F. Therefore, compared with the case where the inner wall 210a of the expansion flow path 210 is formed in a tapered shape as in the conventional check valve 100 shown in FIG. 5, the plate 4 side of the expansion flow path 21 is expanded to the plate 4 side. The cross-sectional area of increases.

  Thereby, in the conventional check valve 100, as shown in FIG. 6A, the flow rate of the fluid F has increased when flowing through the expansion flow path 210, but in the check valve 1 of the present embodiment, As shown in FIG. 4A, an increase in the flow rate of the fluid F flowing through the expansion channel 21 is prevented. Therefore, when the fluid F flows into the through hole 4a of the plate 4, it is possible to prevent the flow rate of the fluid F from rapidly increasing.

  As a result, as shown in FIG. 4B, the pressure distribution in the vicinity of the opening end 4f of the through hole 4a is generally lighter than the pressure distribution of the conventional check valve 100 shown in FIG. 6B. , Pressure drop is suppressed. Therefore, according to the check valve 1 of the present embodiment, it is possible to prevent pressure loss from occurring in the fluid F by providing the inner wall 21 a of the expansion flow path 21 in parallel with the normal line H direction of the plate 4.

  Further, the inner wall 22 a of the plate-side flow path 22 is provided in parallel with the normal H direction of the plate 4, similarly to the inner wall 21 a of the expansion flow path 21. Therefore, the cross-sectional area of the plate-side flow path 22 in the direction parallel to the plate 4 can be made constant from the end portion on the opposite side to the plate 4 to the end portion on the plate 4 side. Thereby, it can prevent that the flow velocity of the fluid F which distribute | circulates the plate side flow path 22 increases. Therefore, when the fluid F flows into the through-hole 4a of the plate 4, it can prevent more effectively that the flow velocity of the fluid F increases.

  As shown in FIG. 3, the dimension L1 of the expansion flow path 21 in the normal H direction of the plate 4 is four times or more than the dimension L2 of the plate-side flow path 22 in the same direction. Therefore, the dimension L1 of the expansion flow path 21 in the normal line H direction of the plate 4 can be sufficiently secured, and the increase in the flow rate of the fluid F flowing through the fluid introduction hole 2b can be more reliably prevented.

Further, by forming the concave curved surface portion 23 between the inner wall 21a of the expansion flow path 21 and the inner wall 22a of the plate side flow path 22, the expansion flow path 21 and the plate side flow path 22 having different cross-sectional areas can be smoothly smoothed. , The pressure loss of the fluid F flowing through the fluid introduction hole 2b can be reduced.
Further, since the opening end of the fluid introduction hole 2b on the plate 4 side is chamfered to form a tapered surface 2t, the flow of the fluid F flowing into the through hole 4a of the plate 4 from the fluid introduction hole 2b of the sheet 2 is further increased. The pressure loss of the fluid F can be reduced by making it linear. Further, by chamfering the periphery of the valve seat surface 2s that contacts the plate 4, it is possible to prevent the seat 2 from biting the plate 4.

  Further, the valve seat surface 2s of the seat 2 is provided so that the edge of the opening end 4f of the plate 4 abuts the valve seat surface 2s when the fluid F is shut off. Thereby, when the through hole 4a of the plate 4 and the fluid outlet hole 3c of the guide 3 are formed to have the same dimensions as those of the conventional check valve 100, the plate-side flow paths 22 of the fluid introduction hole 2b of the seat 2 are connected to each other. The interval can be made narrower than the conventional check valve 100 shown in FIG. And the cross-sectional area of the plate side flow path 22 in the direction parallel to the plate 4 can be increased as compared with the conventional check valve 100. Therefore, it can prevent more effectively that the flow velocity of the fluid F which distribute | circulates the plate side flow path 22 increases. Thereby, when the fluid F flows into the through-hole 4a of the plate 4, it can prevent more effectively that the flow velocity of the fluid F increases.

  Further, the height h of the step G between the inner wall 21a of the expansion channel 21 of the fluid introduction hole 2b of the sheet 2 and the inner wall 22a of the plate-side channel 22 is substantially equal to the sealing width W. Thereby, the cross-sectional area of the expansion flow path 21 of the fluid introduction hole 2b of the sheet 2 is made larger than the cross-sectional area of the plate-side flow path 22 while ensuring a sufficient sealing width W for sealing the fluid F. It becomes possible. Moreover, the space | interval of the expansion flow paths 21 of the some fluid introduction hole 2b can be narrowed, ensuring the intensity | strength of the sheet | seat 2, and the cross-sectional area of the expansion flow path 21 can be made larger than the cross-sectional area of the plate side flow path 22. .

  Further, the inner wall 3e of the fluid outlet hole 3c of the guide 3 is inclined and tapered with respect to the normal line H direction of the plate 4, and a cross-sectional area perpendicular to the normal line H direction of the plate 4 is It forms so that it may expand as it leaves | separates. Thereby, the cross-sectional area of the fluid outlet hole 3c in the direction parallel to the plate 4 can be increased, and the pressure loss of the fluid F flowing through the fluid outlet hole 3c can be reduced.

  As described above, according to the check valve 1 of the present embodiment, when the fluid F flows into the through holes 4a of the plate 4, the flow rate of the fluid F is prevented from increasing rapidly, and the fluid F The pressure loss can be reduced.

  The present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the spirit of the present invention. For example, the fluid introduction hole of the sheet, the through hole of the plate, and the fluid outlet hole of the guide may have a circular shape, an elliptical shape, a polygonal shape, or the like instead of the long hole shape.

It is a perspective view of a check valve in an embodiment of the present invention. It is a fragmentary sectional view of the check valve shown in FIG. It is an expanded sectional view of the principal part of the non-return valve shown in FIG. It is an expanded sectional view of the principal part of the non-return valve shown in FIG. 1, (a) is a figure which shows the flow of a fluid, (b) is a figure which shows the pressure distribution of a fluid. It is an expanded sectional view of the principal part of the conventional check valve. It is an expanded sectional view of the principal part of the conventional check valve, (a) is a figure which shows the flow of the fluid, (b) is a figure which shows the pressure distribution of the fluid in the principal part.

Explanation of symbols

1 check valve, 2 seat (valve seat), 2a outer periphery, 2b fluid introduction hole, 2s valve seat surface, 2t taper surface (chamfering), 21 expansion channel, 21a inner wall, 22 plate side channel (valve plate side) Flow path), 22a inner wall, 23 curved surface, 3 guide (valve holder), 3c fluid outlet hole, 3e inner wall, 4 plate (valve plate), 4a through hole, 4f open end, F fluid, G step, H normal , H Height, L1 dimension, L2 dimension, S gap, W Sealing width

Claims (8)

The fluid is provided with a valve plate in a gap between the valve seat and the valve receiver, allows the fluid flowing in the normal direction of the valve plate from the valve seat side to pass therethrough, and flows in the normal direction from the valve seat side A check valve that shuts off by the valve plate,
The valve seat is formed with a plurality of fluid introduction holes penetrating the valve seat in the normal direction,
The valve receiver is formed with a plurality of fluid outlet holes penetrating the valve receiver in the normal direction,
The fluid introduction hole and the fluid outlet hole are disposed at positions shifted from the normal direction,
The valve plate is formed with a plurality of through holes penetrating the valve plate in the normal direction at positions that do not overlap the fluid introduction hole as viewed from the normal direction but overlap the fluid outlet hole. ,
The fluid introduction hole has a valve plate side channel provided on the valve plate side, and an expansion channel provided on the opposite side of the valve plate,
The cross-sectional area of the expansion channel parallel to the valve plate is larger than the cross-sectional area of the valve plate side channel parallel to the valve plate,
The check valve according to claim 1, wherein an inner wall of the expansion channel is provided in parallel with the normal direction. The valve seat is formed with a valve seat surface that abuts around the opening end of the valve plate on the valve seat side of the through hole of the valve plate and blocks the flow of the fluid,
The check valve according to claim 1, wherein the valve seat surface is provided so that the opening end of the valve plate abuts on the valve seat surface when the fluid is shut off. A step is formed in a direction parallel to the valve plate between the inner wall of the expansion channel and the inner wall of the valve plate side channel,
The height of the step is substantially equal to a sealing width that is an interval between an outer edge of the valve seat surface and the opening end of the valve plate in a direction parallel to the valve plate. Check valve.   The check valve according to any one of claims 1 to 3, wherein an inner wall of the valve plate side flow path is provided in parallel to the normal line direction.   The dimension in the normal direction of the expansion channel is at least four times the dimension in the normal direction of the valve plate side channel. The check valve described.   The check according to any one of claims 1 to 5, wherein a concave curved surface portion is formed between an inner wall of the expansion channel and an inner wall of the valve plate side channel. valve.   The check valve according to any one of claims 1 to 6, wherein an opening end of the fluid introduction hole on the valve plate side is chamfered.   The inner wall of the fluid outlet hole of the valve receiver is provided so as to be inclined with respect to the normal direction so that a cross-sectional area perpendicular to the normal direction increases as the distance from the valve plate increases. The check valve according to any one of claims 1 to 7, wherein:

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