JP7230725B2 - non-return valve - Google Patents

Description

The present invention relates to check valves.

Patent Literature 1 discloses an exhaust tool for a compression storage bag (hereinafter referred to as an exhaust tool). The exhaust device is provided with an outer member having an exhaust window and a valve chamber, and an inner member having a valve seat, only the valve seat protruding outside the compression storage bag. The valve seat portion is provided with a valve holding cylinder and an intake air introduction window. The valve chamber includes a shaft portion held in a hole of the valve holding cylinder (hereinafter referred to as a holding hole), and an umbrella-shaped valve body provided at one end of the shaft portion and positioned closer to the valve seat toward the outer peripheral side. A member is provided. By inserting the shaft portion of the valve member into the holding hole and assembling it to the valve seat, the intake air introduction window of the valve seat is covered with the valve body.

According to such an exhaust device, when the air in the compression storage bag is sucked with a vacuum cleaner or the like, the valve chamber first becomes negative pressure, and the valve body is lifted. , and an exhaust window are communicated. When the exhaust progresses and the suction is stopped when the compression storage bag is sufficiently compressed, the entire valve member descends due to the negative pressure inside the compression storage bag and the valve body sticks to the intake air introduction window, thereby introducing the intake air. close the window. At this time, the valve seat portion and the valve member function as a check valve that prevents the inflow of air from the valve chamber side to the intake air introduction window side, that is, the reverse flow.

Conventionally, a check valve 110 shown in FIGS. 8 and 9 is provided in an oil separator for blow-by gas of an internal combustion engine.
As shown in FIGS. 8 and 9, the oil separator includes an oil trap (not shown) for separating oil from blow-by gas, and an oil reservoir provided below the oil trap for storing the separated oil. 140 are provided. A bottom plate 120 of the oil reservoir chamber 140 is provided with a holding hole 121 and a plurality of oil holes 122 arranged in a circumferential direction around the holding hole 121 . A valve body 130 having a shaft portion 131 attached to the holding hole 121 and a head portion 132 for opening and closing each oil hole 122 is attached to the bottom plate 120 from below. Here, the valve body 130 is assembled by pushing the shaft portion 131 of the valve body 130 into the holding hole 121 .

The check valve 110 is composed of a bottom plate 120 and a valve body 130 . According to the check valve 110 , the umbrella portion 132 normally covers each oil hole 122 from below to prevent blow-by gas from flowing into the oil reservoir chamber 140 through the oil hole 122 , while the oil hole 122 passes through the oil hole 122 . The gravity of the oil acting on the portion 132 causes the umbrella portion 132 to elastically deform, thereby allowing the oil in the oil reservoir chamber 140 to be discharged.

JP 2017-109747 A

By the way, in the case of the conventional check valves shown in FIGS. 8 and 9, when assembling the valve body, an operator checks whether the shaft portion is pushed into the holding hole by a regular amount. It is difficult to determine whether Therefore, it is likely that the valve disc is assembled incorrectly by determining that the valve disc has been assembled even though the valve disc has not been completely assembled.

This problem is not limited to check valves provided in discharge passages for discharging oil, but similarly occurs in check valves provided in discharge passages for discharging other liquids.
SUMMARY OF THE INVENTION An object of the present invention is to provide a check valve capable of suppressing erroneous assembly.

A check valve for achieving the above object is provided in a discharge passage for discharging a liquid, and includes a valve seat having a circular holding hole and a plurality of discharge holes through which the liquid flows, and a shaft part inserted through the holding hole. and a head portion provided on the downstream side of the discharge passage in the shaft portion, the diameter of which is expanded around the shaft portion, and the head portion positioned closer to the valve seat toward the outer peripheral side, While the umbrella closes each of the discharge holes, the umbrella is elastically deformed by the gravity of the liquid acting on the umbrella through the discharge holes, thereby allowing the liquid to be discharged. When the base end side and the tip end side in the axial direction of the shaft portion are defined as the base end side and the tip end side, the inner peripheral edge portion of the base end side of the holding hole is provided with a guide surface whose inner diameter decreases toward the tip end side. A tapered surface extending toward the distal end from a maximum outer diameter portion having an outer diameter larger than the inner diameter of the retaining hole on the distal end side of the holding hole in the shaft portion and having an outer diameter that decreases toward the distal end. and the angle of inclination of the tapered surface with respect to the axis of the shaft is smaller than the angle of inclination of the guide surface with respect to the axis.

According to this configuration, since the shaft is provided with the retaining portion, it is possible to prevent the shaft from falling out of the holding hole of the valve seat.
Further, according to the above configuration, when an operator inserts the tip of the shaft portion into the holding hole in order to assemble the valve body to the valve seat, the tip of the shaft portion is guided along the guide surface toward the center of the holding hole. It will be done. Therefore, the work of inserting the shaft portion into the holding hole can be easily performed. As the shaft portion is inserted into the holding hole, a frictional force acts between the inner peripheral surface of the holding hole and the outer peripheral surface of the shaft portion, thereby generating an insertion load on the valve body. As the shaft portion is further inserted into the holding hole, the retaining portion of the shaft portion enters the retaining hole and is elastically compressed. Therefore, the insertion load increases as the portion of the retaining portion that has entered the holding hole increases. When the maximum outer diameter portion of the retaining portion enters the holding hole, the insertion load becomes maximum. After that, when the retaining portion passes through the holding hole, that is, when the assembly of the valve body is completed, the insertion load is reduced. Therefore, the worker can grasp the completion of the assembly of the valve body by feeling the change in the insertion load through his or her fingers.

In particular, according to the above configuration, the inclination angle of the tapered surface with respect to the axis of the shaft portion is smaller than the inclination angle of the guide surface with respect to the coaxial line. As a result, the length of the retaining portion in the axial direction increases, and the rigidity of the retaining portion increases. Here, as the rigidity of the retaining portion is increased, the retaining portion is less likely to deform, so the amount of increase in the insertion load with respect to the amount of increase in the amount of insertion of the shaft increases, and the maximum value of the insertion load also increases. Become. As a result, when the retaining portion passes through the holding hole, that is, when the assembly of the valve body is completed, the insertion load is greatly reduced, so that the operator can easily feel a large change in the insertion load. You can feel it through your fingers. Therefore, erroneous assembly can be suppressed.

According to the present invention, erroneous assembly of the valve body can be suppressed.

Sectional drawing of the oil reservoir part in which a check valve is provided about one Embodiment of a check valve. Sectional drawing of the oil reservoir part which isolate|separates the valve seat and valve body of the same embodiment from each other. FIG. 4 is a cross-sectional view showing a state in the middle of assembling the valve body to the valve seat; FIG. 4 is a cross-sectional view showing a state in which the retaining portion of the valve body is inserted into the holding hole and compressed. FIG. 5 is a cross-sectional view showing a state in the middle of assembling a valve body to a valve seat of a check valve of a comparative example; FIG. 5 is a cross-sectional view showing a state in which a retaining portion of a valve body is inserted into a holding hole and compressed in a check valve of a comparative example; 4 is a graph showing the relationship between the insertion amount of the shaft portion and the insertion load acting on the valve body when the valve body is assembled to the valve seat. FIG. 4 is a cross-sectional view showing a state in the middle of assembling a valve body to a valve seat of a conventional check valve. FIG. 5 is a cross-sectional view of an oil reservoir provided with a conventional check valve.

An embodiment will be described below with reference to FIGS. 1 and 2. FIG. In this embodiment, the present invention is embodied as a check valve provided in an oil reservoir of an oil separation device that separates oil from blow-by gas of an internal combustion engine.

As shown in FIG. 1, the oil reservoir 40 stores oil separated by an oil trap (not shown) of the oil separation device, and discharges the stored oil to the outside when it reaches a predetermined amount or more. .

The oil reservoir 40 has a cylindrical peripheral wall 42 extending in the vertical direction, a disk-shaped valve seat 20 provided inside the peripheral wall 42 and partitioning the interior into upper and lower parts, and attached to the valve seat 20 from below. A valve body 30 is provided. The internal space of the oil reservoir 40 constitutes a discharge passage 41 through which the oil is discharged. The oil reservoir 40 is preferably integrally molded, for example, from a hard resin material.

As shown in FIGS. 1 and 2, a circular holding hole 21 is formed in the center of the valve seat 20 so as to pass through the valve seat 20 in the thickness direction (vertical direction in FIG. 2).
A plurality of discharge holes 22 are arranged in the valve seat 20 in a circumferential direction around the holding hole 21 . In this embodiment, four circular discharge holes 22 are arranged at regular intervals in the circumferential direction.

As shown in FIGS. 1 and 2, the valve body 30 has a shaft portion 31 inserted and held in the holding hole 21, and the diameter of the valve body 30 is expanded around the shaft portion 31 and positioned closer to the valve seat 20 toward the outer peripheral side. It has an umbrella portion 32 . The valve body 30 is integrally molded with an elastic member. A rubber material, for example, is preferable as the elastic member. The valve body 30 is attached to the valve seat 20 by fitting the shaft portion 31 into the holding hole 21 .

Hereinafter, the proximal side (lower side in FIGS. 1 and 2) and the distal side (upper side in FIGS. 1 and 2) in the axial direction of the shaft portion 31 will be simply referred to as the proximal side and the distal side.
A guide surface 21a is provided on the inner peripheral edge portion of the holding hole 21 on the proximal side, the inner diameter of which decreases toward the distal end.

On the distal end side of the holding hole 21 in the shaft portion 31 , a tapered surface 33 b extends from a maximum outer diameter portion 33 a having an outer diameter larger than the inner diameter of the holding hole 21 toward the distal end side and has a smaller outer diameter toward the distal end side. is provided. A tip portion 33 c of the tapered surface 33 b of the shaft portion 31 has an outer diameter smaller than the inner diameter of the holding hole 21 . A portion 31a on the tip side of the tapered surface 33b of the shaft portion 31 has the same outer diameter as the tip portion 33c of the tapered surface 33b over the entire axial direction. The length of the tapered surface 33b in the axial direction is greater than the length of the holding hole 21 in the axial direction.

A facing portion 34 having a larger diameter than the maximum inner diameter of the guide surface 21 a and facing the base end surface 20 a of the valve seat 20 is provided at the base end portion of the shaft portion 31 . The valve seat 20 is held between the retaining portion 33 and the facing portion 34 in the axial direction.

Here, the inclination angle α of the tapered surface 33b with respect to the axis L of the shaft portion 31 is smaller than the inclination angle β of the guide surface 21a with respect to the axis L (see FIG. 2).
The check valve 10 is composed of the valve seat 20 and the valve body 30 described above.

In such a check valve 10 , each discharge hole 22 is always closed by the umbrella portion 32 . On the other hand, when the amount of oil separated from the blow-by gas and stored in the oil reservoir 40 exceeds a predetermined amount, the gravity of the oil acting on the head 32 through the discharge hole 22 causes the head 32 to elastically deform. Drainage of oil is allowed.

Next, the effects of this embodiment will be described.
As shown in FIG. 3, when an operator inserts the tip of the shaft portion 31 into the holding hole 21 to assemble the valve body 30 to the valve seat 20, the tip of the shaft portion 31 moves along the guide surface 21a. directed towards the center.

As the insertion of the shaft portion 31 into the holding hole 21 progresses, a frictional force acts between the inner peripheral surface of the holding hole 21 and the outer peripheral surface of the shaft portion 31, thereby generating an insertion load on the valve body 30. become.
As shown in FIG. 4 , when the shaft portion 31 is further inserted into the holding hole 21 , the retainer portion 33 of the shaft portion 31 enters the holding hole 21 while being elastically compressed. After that, when the retaining portion 33 passes through the holding hole 21, that is, when the assembly of the valve body 30 is completed, the insertion load is reduced. Therefore, the worker can grasp the completion of the assembly of the valve body by feeling the change in the insertion load through his or her fingers.

In particular, in this embodiment, the inclination angle α of the tapered surface 33b is smaller than the inclination angle β of the guide surface 21a. For this reason, compared to the check valve 210 of the comparative example shown in FIGS. As the length of the portion 33 in the axial direction increases, the rigidity of the retaining portion 33 increases. Note that, among the configurations of the check valve 210 of the comparative example, the configuration that is the same as or corresponds to the configuration of the check valve 10 of the present embodiment is added to each symbol "**" of the present embodiment by "200". Duplicate description is omitted by attaching the reference numerals "2**". Here, as the rigidity of the retaining portion 33 is increased, the retaining portion 33 is less likely to deform. Therefore, according to the check valve 10 of the present embodiment, as shown by the solid line in FIG. The maximum value of the insertion load increases as the amount of increase in the insertion load increases. Specifically, in the check valve 10 of the present embodiment, when the amount of insertion of the shaft portion 31 into the holding hole 21 reaches S1, which is larger than 0, the inner peripheral surface of the holding hole 21 and the outer peripheral surface of the retaining portion 33 In addition to the frictional force acting on the tapered surface 33b, the retaining portion 33 enters the holding hole 21 while being elastically compressed. Therefore, the insertion load increases substantially in proportion to the increase in the amount of insertion of the shaft portion 31 . Then, when the insertion amount of the shaft portion 31 reaches S3, which is larger than S1, the maximum outer diameter portion 33a enters the holding hole 21 while being elastically compressed, thereby maximizing the insertion load.

After that, when the insertion amount of the shaft portion 31 reaches S4, which is larger than S3, the retaining portion 33 passes through the holding hole 21, so the insertion load is reduced. Then, when the amount of insertion of the shaft portion 31 reaches S5, which is larger than S4, the assembly of the shaft portion 31 is completed.

On the other hand, in the check valve 210 of the comparative example, when the amount of insertion of the shaft portion 231 reaches S2 or more, which is larger than S1, the insertion load increases substantially in proportion to the increase in the amount of insertion of the shaft portion 231 . However, the amount of increase in the insertion load with respect to the amount of increase in the amount of insertion of the shaft portion 231 at this time, that is, the inclination of the insertion load, is due to the lower rigidity of the retaining portion 233 than in the check valve 10 of the present embodiment. small.

As a result, in the check valve 10 of the present embodiment, when the retaining portion 33 passes through the holding hole 21, that is, the insertion amount of the shaft portion 31 reaches S4, which is larger than S3, and the retaining portion 33 is retained. When passing through the hole 21, the insertion load is reduced more than the check valve 210 of the comparative example. Therefore, the operator can feel a large change in the insertion load through his or her fingers.

In addition, in the conventional check valve 110 shown in FIGS. 8 and 9, the shaft portion 131 of the valve body 130 has an outer diameter slightly larger than the inner diameter of the holding hole 121 . Therefore, as indicated by the dashed line in FIG. 7, when the amount of insertion of the shaft portion 131 becomes greater than 0, the insertion load increases substantially in proportion to the increase in the amount of insertion of the shaft portion 131 . Further, when the amount of insertion of the shaft portion 131 is further increased, the entire inner peripheral surface of the holding hole 121 comes into pressure contact with the outer peripheral surface of the shaft portion 131, and the insertion load becomes maximum. After that, even if the amount of insertion of the shaft portion 131 is further increased, since the contact area between the inner peripheral surface of the holding hole 121 and the outer peripheral surface of the shaft portion 131 remains constant, the insertion load remains constant at the maximum value. Become.

Next, the effects of this embodiment will be described.
(1) The inclination angle α of the tapered surface 33b with respect to the axis L of the shaft portion 31 is smaller than the inclination angle β of the guide surface 21a with respect to the axis L.

According to such a configuration, the operator can feel a large change in the insertion load acting on the valve body 30 when the retaining portion 33 passes through the holding hole 21, that is, when the assembly of the valve body 30 is completed. You can feel it through your fingers. Therefore, erroneous assembly of the valve body 30 to the valve seat 20 can be suppressed.

(2) The length of the tapered surface 33b in the axial direction is greater than the length of the holding hole 21 in the axial direction.
As described above, when the maximum outer diameter portion 33a of the retaining portion 33 enters the holding hole 21 and the insertion load becomes maximum, the maximum outer diameter portion 33a passes through the holding hole 21. The insertion load becomes constant. Here, if the insertion load continues to be constant while the shaft portion 31 is being inserted into the holding hole 21, the worker may be required to assemble the valve body 30 even though the assembling is not completed. It is easy to erroneously conclude that is complete.

In this respect, according to the above configuration, since the length of the holding hole 21 in the axial direction can be shortened, the maximum outer diameter portion 33a of the retaining portion 33 enters the holding hole 21, thereby maximizing the insertion load. It is possible to shorten the period from when the maximum outer diameter portion 33a passes through the holding hole 21, that is, when the insertion load is constant. Therefore, it is possible to prevent the operator from erroneously judging that the assembly of the valve body 30 has been completed even though the assembly of the valve body 30 has not been completed.

(3) A tip portion 33 c of the tapered surface 33 b of the shaft portion 31 has an outer diameter smaller than the inner diameter of the holding hole 21 . A portion 31a on the tip side of the tapered surface 33b in the shaft portion 31 has the same outer diameter as the tip portion 33c of the tapered surface 33b.

According to such a configuration, the distal end side portion of the shaft portion 31 can be quickly inserted into the holding hole 21 . Therefore, the operation of inserting the shaft portion 31 into the holding hole 21 is further facilitated.
(4) A facing portion 34 having a diameter larger than the maximum inner diameter of the guide surface 21a and facing the lower surface of the valve seat 20 in the thickness direction is provided at the base end portion of the shaft portion 31. . The valve seat 20 is sandwiched between the retaining portion 33 and the facing portion 34 .

With such a configuration, the valve seat 20 is sandwiched between the retaining portion 33 and the facing portion 34 , so that the valve body 30 is stably held against the valve seat 20 . As a result, the function of the check valve 10 can be exhibited more stably.

(5) Since the shaft portion 31 is provided with the retaining portion 33 , the shaft portion 31 can be prevented from falling out of the holding hole 21 of the valve seat 20 .
(6) When an operator inserts the tip of the shaft portion 31 into the holding hole 21 to assemble the valve body 30 to the valve seat 20, the tip of the shaft portion 31 is directed toward the center of the holding hole 21 along the guide surface 21a. be guided. Therefore, the operation of inserting the shaft portion 31 into the holding hole 21 can be easily performed.

<Change example>
This embodiment can be implemented with the following modifications. This embodiment and the following modified examples can be implemented in combination with each other within a technically consistent range.

- The facing portion 34 can be omitted. That is, the base end side portion of the shaft portion 31 does not have to be expanded beyond the maximum inner diameter of the guide surface 21a. Further, the valve seat 20 may not be sandwiched between the retaining portion 33 and the facing portion 34 .

A tip portion 33c of the tapered surface 33b of the shaft portion 31 may have an outer diameter equal to or larger than the inner diameter of the holding hole 21. - 特許庁
A portion 31a on the tip side of the tapered surface 33b of the shaft portion 31 may be tapered toward the tip. Also, the portion 31a on the tip side can be omitted.

- The length of the tapered surface 33b in the axial direction may be equal to or less than the length of the holding hole 21 in the axial direction.

DESCRIPTION OF SYMBOLS 10, 110... Check valve 20... Valve seat 20a... Surface 21, 121... Holding hole 21a... Guide surface 22, 122... Discharge hole 30, 130... Valve body 31, 131... Shaft part, Reference numerals 32, 132: Head portion 33: Retaining portion 33b: Tapered surface 34: Opposing portion 40, 140: Oil reservoir 41: Discharge passage 42: Peripheral wall 120: Bottom plate

Claims (4)

A valve seat provided in a discharge passage for discharging a liquid and having a circular holding hole and a plurality of discharge holes through which the liquid flows, a shaft inserted through the holding hole, and a downstream side of the discharge passage in the shaft. and a valve body having a head portion which expands in diameter around the shaft portion and is positioned closer to the valve seat toward the outer peripheral side, wherein the head portion always closes each of the discharge holes. On the other hand, in the check valve that allows the liquid to be discharged by elastically deforming the head portion due to the gravity of the liquid acting on the head portion through the discharge hole,
When the proximal side and the distal side in the axial direction of the shaft portion are defined as the proximal side and the distal side,
A guide surface having an inner diameter that decreases toward the distal end is provided on the inner peripheral edge of the holding hole on the proximal side,
A tapered surface extending toward the distal end from a maximum outer diameter portion having an outer diameter larger than the inner diameter of the retaining hole is provided on the distal end side of the holding hole in the shaft portion, and the outer diameter decreases toward the distal end. A retaining part is provided,
an inclination angle of the tapered surface with respect to the axis of the shaft portion is smaller than an inclination angle of the guide surface with respect to the axis;
non-return valve. the length of the tapered surface in the axial direction is greater than the length of the holding hole in the axial direction;
The check valve according to claim 1. A tip portion of the tapered surface of the shaft portion has an outer diameter smaller than an inner diameter of the holding hole,
A portion of the shaft portion closer to the distal end than the distal end of the tapered surface has an outer diameter equal to or smaller than that of the distal end portion of the tapered surface.
The check valve according to claim 1 or 2. The base end portion of the shaft portion is provided with a facing portion having a larger diameter than the maximum inner diameter of the guide surface and facing the base end surface of the valve seat,
The valve seat is sandwiched between the retaining portion and the facing portion.
The check valve according to any one of claims 1 to 3.

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