TW201932713A - Check valve characterized by surely close a check valve to not allow water to flow into an air driving portion, when the supply of air to an air route is interrupted - Google Patents

Abstract

To surely close a check valve and not allow water to flow into an air driving portion, when the supply of air to an air route is interrupted. The check valve (5) of the present invention is installed in a mechanism (1) equipped with: a supplying portion (300) used to supply a mixture of air and water; a mixing portion (32) used to mix the air and water; a communicating route (31) used to communicate the mixing portion (32) with the supplying portion (300); an air route (41) used to communicate the mixing portion (32) with an air source (40); a water route (37) used to communicate the mixing portion (32) with a water source (38); and an air supplying route (46) communicating with an air driving portion (47) and installed in a branch portion (42) of the air route (41). Between the mixing portion (32) and the branch portion (42), the check valve can stop water flowing into the air driving portion (47) from the mixing portion (32) and is equipped with: a cylinder (50) which allows a lower end to communicate with the mixing portion (32), allows an upper end to communicate with the air source (40) and is vertically arranged; and a floating body (51) which floats on a water surface of the water flowing into the cylinder (50) from the lower end and moves up and down. If the floating body (51) is located at the upper end in the cylinder (50), it can block the air route (41). If the floating body (51) is away from the upper end in the cylinder (50), the air can be supplied to the mixing portion (32).

Description

Check valve

The present invention relates to a check valve for preventing water from flowing backward.

A processing apparatus for processing a semiconductor wafer or the like may mix water and air necessary for processing in the apparatus. For example, a grinding device for wafer grinding is a method in which a mixed fluid that mixes water and air is ejected from a holding surface when a wafer is detached from a chuck table that sucks and holds the wafer. In addition, when the wafer is cleaned, water and air are mixed and ejected from the nozzle toward the wafer.

As described above, in the processing apparatus, air and water are mixed in a mixing section in the apparatus.
In addition, the air path connecting the mixing section and the air supply source is divided in the device through a branching section, and the branched air path is connected to an air drive such as an air cylinder or an air mandrel that operates by air supply. unit.

Due to an accident at the air supply source, the supply of air to the air path is interrupted, the air pressure in the air path decreases, and water supplied by the water supply source may enter the air path due to the water pressure. Then, this water may reach the air drive part, and the air drive part may be damaged. In order to prevent damage as shown above, a spring-loaded check valve is installed closer to the mixing section side (more downstream side) than the branching portion where the air path diverges in the air-driven part, so that water does not flow to Air supply source side (see, for example, Patent Document 1).
[Prior technical literature]
[Patent Literature]

[Patent Document 1] Japanese Patent Laid-Open No. 2014-003186

(Problems to be solved by the invention)

However, when the supply of air to the air path is interrupted, there is a problem that the spring-type check valve is not properly closed.
Therefore, when the supply of air to the air path is interrupted, there is a problem that the check valve is reliably closed and water does not flow to the air drive unit.

(Means for solving problems)

The present invention for solving the above-mentioned problems is a check valve provided with a supply unit that supplies a mixed fluid that mixes air and water; a mixing unit that mixes air and water; and the mixing unit and the supply unit A communication path that communicates; an air path that communicates the mixing section with the air supply source; a water path that communicates the mixing section with the water supply source; and a branching section disposed on the air path A mechanism for supplying an air supply path that communicates with a driving air drive unit is disposed between the mixing unit and the branching unit, and a check valve that stops water from flowing from the mixing unit to the air drive unit, the check valve The valve system is provided with a cylinder standingly connected to the lower end to communicate with the mixing unit and an upper end to the air supply source, and a floating body that floats on the water surface of the water that enters the cylinder from the lower end and moves upward and downward. If the floating body is positioned at the upper end in the cylinder, the air path is blocked, and if the floating body is far from the upper end in the cylinder, air can be supplied to the mixing section.

It is preferable that the lower part inside the said cylinder is provided with the shielding part which suppresses the flow velocity of the water which entered the said cylinder from the said lower end.

(Effect of the invention)

The check valve of the present invention is provided with: a supply section that supplies a mixed fluid that mixes air and water; a mixing section that mixes air and water; a communication path that communicates the mixing section and the supply section; and a mixing section and air An air path communicating with a supply source; a water path communicating a mixing section with a water supply source; and an air supply path communicating with a branching section of the air path and communicating with an air drive section driven by air supply The mechanism is a check valve arranged between the mixing section and the branching section to prevent water from flowing from the mixing section to the air drive section. The check valve is provided with a lower end communicating with the mixing section and an upper end communicating with The air supply source is connected to the tank and the tank is upright; and the floating body floats on the water surface that enters the tank from the lower end and moves up and down. Therefore, if air is supplied from the air supply source to the air path due to an accident, etc. When the pressure of the air in the air path is interrupted and the pressure of the water supplied from the water supply source is lower, the floating body floating on the water surface of the water entering the cylinder will block the air path and prevent the water from flowing more than the check valve. Pick up An air supply source side of the path of the air, the water does not enter the drive unit to the air. In addition, if the water pressure drops and the floating body moves away from the upper end of the cylinder, air can be supplied to the mixing section.

The lower part of the barrel is provided with a shielding portion that suppresses the flow rate of water entering the barrel from the lower end. When the check valve must be closed, it is possible to prevent the water flowing into the barrel from lowering the floating body. An event occurs in which a force and a flow path are formed in the check valve.

The mechanism 1 shown in FIG. 1 is, for example, a cutting processing device that is arranged to cut with a cutter (not shown) and cuts a workpiece that is attracted and held on the holding platform 30, or a grinding vermiculite (not shown) is attracted. A mechanism such as a grinding processing device that holds the workpiece to be held on the holding platform 30 to a desired thickness is provided with the check valve 5 of the present invention.

The holding platform 30 shown in FIG. 1 has, for example, a circular shape and includes a porous member or the like, which can absorb plate-shaped objects such as semiconductor wafers, and can supply a mixed fluid that mixes air and water. To the supply unit 300 on the holding platform 30; and the frame 301 supporting the supply unit 300.

The exposed surface of the supply unit 300 is capable of attracting the holding surface 300 a that holds the plate-shaped workpiece. As shown in FIG. 1, for example, one end 31 a of a communication path 31 formed of a metal pipe or a flexible resin pipe penetrates the bottom of the frame 301 holding the platform 30 and communicates with the supply unit 300. The other end 31b side of the communication path 31 is in communication with a mixing section 32 that mixes air and water.

A branching path 33 is branched from the communication path 31, and a suction source 39 formed by a vacuum generating device such as a vacuum pump or an ejector is connected to the branching path 33. The branch path 33 is provided with a vacuum valve 330 that can be switched between a state in which the branch path 33 communicates with the suction source 39 and a state in which it is opened to the atmosphere.
When the vacuum valve 330 is opened, the attraction force generated by the operation of the suction source 39 is transmitted to the holding surface 300a of the supply unit 300 through the branch path 33 and the communication path 31, whereby the holding platform 30 can hold the The workpiece 300 is attracted and held on the surface 300a.

The mixing section 32 is, for example, a room provided with three connection ports. One of the connection ports is connected to the other end 31b of the communication path 31 as described above, and the other one of the connection ports is connected to the water path 37 for supplying water. One end. A water supply source 38 composed of a pump or the like is connected to the other end of the water path 37. A water stop valve 371 that controls the opening and closing of the water passage 37 is provided on the water path 37 that connects the mixing unit 32 and the water supply source 38, and is connected to the water passage 37 further downstream than the water stop valve 371. There is a throttle valve 372 for adjusting the amount of water flowing into the mixing section 32.

One end 41 a of the air path 41 that connects the mixing section 32 and the air supply source 40 is connected to still another connection port of the mixing section 32. The air supply source 40 formed by a compressor, an air storage tank, and the like and connected to the other end 41 b side of the air path 41 allows the compressed air to flow into the air path 41. On the upstream side (the other end 41b side) of the air path 41, a branching portion 42 such as a tripartite pipe is arranged. The branching portion 42 is connected to the other end of the air supply path 46 which communicates with the air driving portion 47 at one end. The air drive unit 47 is, for example, an air cylinder or an air mandrel (operated by a pressure of an air layer formed in a gap between the housing and the rotating shaft to support the rotating shaft in a non-contact manner), which operates by air supply.

(1) Embodiment 1 of a check valve
The check valve 5 of the present invention (hereinafter referred to as the check valve 5 of the first embodiment) is arranged on the downstream side of the air path 41 from the branch portion 42, that is, between the branch portion 42 and the mixing portion 32. The check valve 5 having a specific structure shown in FIG. 2 (A) includes, for example, a cylinder 50 made of metal or plastic and having a substantially cylindrical space inside and standing upright; and a housing 50 accommodated in the cylinder 50. The floating body 51 functions to prevent water from flowing from the mixing unit 32 to the air driving unit 47.

The upper end 50a of the cylinder 50 is in communication with the air supply source 40 through the branch portion 42 through a pipe constituting the air path 41, and the lower end 50b of the cylinder 50 is in communication with the mixing portion 32 through a pipe constituting the air path 41. For example, as shown in FIG. 1, between the check valve 5 in the air path 41 and the mixing section 32, a state switchable to communicate the air path 41 and the air supply source 40 is provided, and is opened to the atmosphere. State of the air valve 44. A throttle valve 45 is provided on the downstream side of the air valve 44 to adjust the flow rate of the air flowing into the mixing section 32.
2 (A), (B), 3 (A), (B), and 6 (A), (B), the water supply source 38 to the lower end 50b of the check valve 5 are omitted. Part of the composition.

As shown in FIG. 2 (A), the floating body 51 has, for example, a spherical shape and is made of metal or plastic having a specific gravity smaller than that of water. As shown in FIG. 2 (A), although the inside of the cylinder 50 is formed as a cylindrical space in this embodiment, it may be formed as a corner cylindrical space. As shown in this embodiment, if the inside of the cylinder 50 is formed into a cylindrical space, the inner diameter of the cylinder 50 is greater than the diameter of the floating body 51. When the inside of the cylinder 50 is formed into a corner columnar space, the length of one side of the corner column ≧ the diameter of the floating body 51.

For example, on the side of the upper end 50a inside the cylinder 50, a tapered abutment surface with which the inner diameter decreases as the diameter of the floating body 51 decreases toward the upper end 50a, and the floating body 51 abuts when the valve is closed. 50c. An opening of the water inlet 50d is formed at a position substantially at the center of the lower end 50b side of the inside of the cylinder 50.

For example, the lower part inside the cartridge 50 is provided with a shielding part 52 which suppresses the flow velocity of the water which enters into the cartridge 50 from the water inlet 50d. The shielding portion 52 shown in FIG. 2 (A) is, for example, inside the tube 50, from the inner peripheral surface of the -X direction side (the inner side of the paper surface) to the + X direction side (the paper surface and the front side) based on the inner center of the tube 50. The inner peripheral surface of the plate extends over the existing water inlet 50d. The width in the Y-axis direction of the shielding portion 52 is smaller than the inner diameter of the tube 50, and a gap is formed between the shielding portion 52 and the inner peripheral surface of the tube 50. The shielding portion 52 is located below the floating body 51 in the cylinder 50, for example, and also plays a role in regulating the movement of the floating body 51. Therefore, the floating body 51 does not move below the shielding portion 52 when the air is supplied. A case where the water inlet 50d of the lower end 50b is closed to the side and the air path 41 is closed.
However, the shape of the plate-shaped shielding portion 52 is not limited to the example shown in FIG. 2 (A), and may extend in a semicircular shape so as to cover the upper end of the water inlet 50d of the lower end 50b in the cylinder 50.

As shown in FIG. 2 (A), in a state where air is supplied to the air path 41 from the air supply source 40, the floating body 51 is formed to ride on the upper surface of the shielding portion 52 without closing the upper end 50 a side of the inside of the cylinder 50. status. The air supplied to the air path 41 from the air supply source 40 flows into the cylinder 50 from the upper end 50a side, and flows through the gaps on both sides of the shielding portion 52 from the water inlet 50d at the lower end 50b to the pipes constituting the air path 41. And it reaches the mixing part 32 by the air valve 44 (refer FIG. 1) of an open state.
In addition, water is supplied from the water supply source 38 to the water path 37, whereby the water system reaches the mixing section 32 through the open water stop valve 371, and air and water are mixed in the mixing section 32. Next, the mixed flow system in the mixing section 32 passes through the communication path 31 and reaches the supply section 300 shown in FIG. 1, so that the mixed fluid can be ejected from the holding surface 300 a. However, since the vacuum valve 330 is closed, there is no case where the mixed fluid passes through the branch path 33 and flows into the suction source 39.

In the state shown in FIG. 2 (A), for example, if an accident occurs in the air supply source 40 and the supply of air to the air path 41 is interrupted, the air pressure in the air path 41 decreases, as shown in the state shown in FIG. 2 (B). The water supplied from the water supply source 38 flows into the air path 41 from the mixing section 32 and passes through the air valve 44 (see FIG. 1) in an opened state to enter the cartridge 50 from the water inlet 50 d on the lower end 50 b side.

Here, when the water system collides with the lower surface of the shielding portion 52, the water flow rate rises in the cylinder 50 while entering the inside of the cylinder 50 while decreasing the flow velocity. With this, the floating body 51 floats on the water surface of the water entering the cylinder 50 and rises together with the water surface, and abuts against the abutment surface 50c in the cylinder 50 and is positioned at the upper end 50a, whereby the check valve 5 is closed. status. Therefore, since the air path 41 is blocked, the water flowing into the air path 41 from the mixing section 32 can be prevented from flowing into the air driving section 47.

In addition, by providing a shielding portion 52 at the lower portion of the inside of the cylinder 50 to suppress the flow rate of water entering the cylinder 50 from the lower end 50b, it is possible to prevent the water entering the cylinder 50 from lowering and forming the floating body 51. Events in the flow path occurred. That is, if the shielding portion 52 is not provided, the water entering the cylinder 50 directly collides with the floating body 51 strongly, so turbulent flow occurs in the cylinder 50, and the floating body 51 does not float to the water surface in the cylinder 50. On the other hand, when being pulled into the water, the water surface in the cylinder 50 may rise while being irregularly moved or submerged in the water. At this time, before the floating body 51 abuts the abutting surface 50c, the water surface reaches the upper end 50a, and a state in which the air path 41 is not closed by the check valve 5 may occur. However, as shown in this embodiment, since the check valve 5 is provided with the shielding portion 52, the water flow entering the cylinder 50 will not directly collide with the floating body 51 with a strong momentum. Therefore, the floating body 51 floats to the cylinder 50. The inner water surface does not move irregularly and rises. Therefore, the check valve 5 is in a state where the check valve 5 is surely closed.
However, depending on the amount of water supplied from the water supply source 38, the check valve 5 may be formed without a shielding portion 52.

For example, the operator solves the accident of the air supply source 40, so that if the air is again supplied to the air path 41 from the air supply source 40, the air flows into the cylinder 50 from the upper end 50a side, and the air pressure in the cylinder 50 Increasing, relatively, the water pressure in the cylinder 50 is lowered, whereby the water surface in the cylinder 50 is lowered and the floating body 51 is separated from the abutment surface 50c of the upper end 50a of the cylinder 50. The state in which the return valve 5 is opened is formed as described above, whereby the air passing through the air path 41 is supplied to the mixing section 32 in the same manner as described above.

(2) Embodiment 2 of a check valve
A check valve 5A of the second embodiment shown in Figs. 3 (A) and (B) described below may be provided on the downstream side of the branching portion 42 of the air path 41 instead of Figs. 2 (A) and 2 (A). (B) The check valve 5 of the first embodiment shown.
The check valve 5A of the second embodiment is the same as that of the check valve 5 of the first embodiment in that the shielding portion 52 and the water inlet 50d of the check valve 5 of the first embodiment are changed.
On the lower end 50b side of the check valve 5A, a water inlet 50e through which water from the water supply source 38 flows is extended upward inside the side wall of the cylinder 50, and then curved inward in the radial direction to form an opening in the lower portion of the inner peripheral surface of the cylinder 50. . Next, the above-mentioned meandering portion of the water inlet 50e functions as a shielding portion 54 that suppresses the flow velocity of the water entering the tube 50 from the lower end 50b, and the water system enters the tube 50 from the lateral side.
Between the opening at the lower part of the inner peripheral surface of the cylinder 50 of the water inlet 50e and the floating body 51 located at the lower end 50b, a gap through which air directed toward the mixing section 32 can pass is constantly formed. Among them, for example, protrusions (not shown) may be arranged around the opening at the lower portion of the inner peripheral surface of the cylinder 50 of the water inlet 50e, and the floating body 51 will not block the water inlet 50e by a plurality of intervals. The case where the lower part of the inner peripheral surface of the cylinder 50 is opened.

As shown in FIG. 3 (A), in a state where air is supplied to the air path 41 from the air supply source 40, the floating body 51 is positioned at the lower end 50b in the cylinder 50, and the check valve 5A is opened. Therefore, air flows into the cylinder 50 from the upper end 50a side, flows from the water inlet 50e on the lower end 50b side to the piping constituting the air path 41, and reaches the mixing section 32 through the open air valve 44 (see FIG. 1). In addition, water is supplied into the mixing section 32 from the water supply source 38 through the water path 37 in an opened state, and air and water are mixed. Then, the mixed flow system is ejected from the holding surface 300 a of the supply unit 300 through the communication path 31.

In the state shown in FIG. 3 (A), for example, if the supply of air to the air path 41 is interrupted due to an accident with the air supply source 40 and the air pressure in the air path 41 decreases, as shown in FIG. 3 (B), the water The water supplied from the supply source 38 flows into the air path 41 from the mixing section 32 and enters the tube 50 through the water inlet 50e on the lower end 50b side. When this water system collides with the shielding part 54 in the water inlet 50e, the flow velocity when it enters the inside of the cylinder 50 will fall. Next, the floating body 51 floats on the water surface of the water entering into the cylinder 50 from the lateral side and rises together with the water surface, and abuts against the abutment surface 50c in the cylinder 50 and is positioned at the upper end 50a, whereby the check valve 5A Since the air path 41 is closed and the air path 41 is closed, the water flowing into the air path 41 from the mixing section 32 can be prevented from flowing into the air driving section 47.

In addition, by including a shielding portion 54 in the lower portion of the cylinder 50 to suppress the flow velocity of water entering the cylinder 50 from the lower end 50b, it is possible to prevent the water flowing into the cylinder 50 from lowering the force of the floating body 51 and forming a flow. Things happened on the road.

For example, if the operator solves the accident of the air supply source 40, if the air is again supplied to the air path 41 from the air supply source 40, the air flows into the cylinder 50 from the upper end 50a side and the water pressure in the cylinder 50 decreases. The water surface in the cylinder 50 is lowered and the floating body 51 is away from the abutting surface 50 c of the cylinder 50. Since the check valve 5A is opened, air passing through the air path 41 is supplied to the mixing section 32.

(3) Embodiment 3 of a check valve
A check valve 5B according to the third embodiment shown in Figs. 4 (A) and (B) described below may be provided on the downstream side of the branch portion 42 of the air path 41 instead of Figs. 2 (A) and 2 (A). (B) The check valve 5 of the first embodiment shown.
The check valve 5B shown in FIGS. 4 (A) and 4 (B) is the same as the check valve 5 of the first embodiment, and includes an upright tube 50 having a cylindrical space inside, and a tube 50 accommodated therein. Within the floating body 51. A second sleeve 56 having a short cylindrical shape is attached to the opening at the upper end 50a side of the cylinder 50, and a first sleeve 55 having a substantially cylindrical shape is attached to the opening at the lower end 50b side.

The second sleeve 56 on which the flow path 560 having a diameter less than the diameter of the floating body 51 is formed is provided with a flange-shaped catching portion 561 extending outward in the radial direction on the upper end side. For example, the lower end side of the flow path 560 is formed with a tapered abutment surface 560c to which the floating body 51 abuts when the check valve 5B is closed. As shown in FIG. 4 (B), the second sleeve 56 is, for example, fitted into an opening on the upper end 50a side of the cylinder 50, and the catching portion 561 abuts on the upper end surface of the cylinder 50 without being deviated in the vertical direction. It is situationally mounted on the cartridge 50.

The first sleeve 55 is provided with a fitting portion 550 having an outer diameter slightly smaller than the inner diameter of the barrel 50 and fitted into the barrel 50; the fitting portion 550 is formed to have a smaller diameter than the fitting portion 550 and is fitted by the fitting portion 550 A shielding portion 551 protruding upward and suppressing the flow rate of water entering the tube 50 from the lower end 50b; and a flange-shaped catching portion 552 extending outwardly in the radial direction from the lower end side of the fitting portion 550. A flow path 553 is formed from the lower end side of the fitting part 550 to the shielding part 551, and the upper end side of the flow path 553 is divided in the shielding part 551 at equal intervals in the circumferential direction and extends outward in the radial direction. An opening is formed in the outer peripheral surface of the shielding portion 551.

As shown in FIG. 4 (B), the first sleeve 55 is inserted into the opening on the lower end 50b side of the cylinder 50, and the catching portion 552 abuts on the lower end surface of the cylinder 50 without being deviated in the vertical direction. The ground is mounted on the canister 50. Next, the floating body 51 is formed on the upper surface of the shielding portion 551, and a gap is formed between the inner peripheral surface of the tube 50 and the outer peripheral surface of the shielding portion 551.
On the upper and lower end sides of the check valve 5B assembled as shown in FIG. 4 (B), and as shown in FIG. 5, one-touch joints 58A and B, which can be installed with one-touch, are installed, respectively. The joints 58A and B are connected to a pipe constituting the air path 41. The check valve 5B configured as described above can be assembled or disassembled without using tools or using simple tools, for example, and can be easily packed in the cartridge 50 after use.

As shown in FIG. 6 (A), in a state where air is supplied to the air path 41 from the air supply source 40, the floating body 51 is located at the lower end 50b in the cylinder 50 and the check valve 5B of the third embodiment is opened. . Therefore, the air flows into the cylinder 50 from the upper end 50a side through the flow path 560 of the one-touch joint 58A and the second sleeve 56 and flows through the flow path 553 of the first sleeve 55 and the one-touch joint 58B. It reaches the pipe which comprises the air path 41, and reaches the mixing part 32. In addition, water is supplied into the mixing section 32 from the water supply source 38 through the water path 37 and the air and water are mixed. Next, the mixed flow system is ejected from the holding surface 300 a (see FIG. 1) of the supply unit 300 through the communication path 31.

In the state shown in FIG. 6 (A), for example, if the supply of air to the air path 41 is interrupted due to an accident with the air supply source 40 and the air pressure in the air path 41 decreases, as shown in FIG. 6 (B), the water The water supplied from the supply source 38 flows into the air path 41 from the mixing section 32. This water system passes through the shielding portion 551 of the first sleeve 55 and enters the tube 50 from the lower end 50b side after the flow velocity is suppressed. Next, there is no case where the water flow directly hits the floating body 51. The floating body 51 floats on the water surface of the water entering the cylinder 50 and rises together with the water surface, and abuts against the abutment surface 560c of the second sleeve 56 and is positioned At the upper end 50 a of the cartridge 50, the check valve 5B is closed and the air path 41 is blocked, thereby preventing the water flowing into the air path 41 from the mixing section 32 from flowing into the air driving section 47.

In addition, by providing a shielding portion 551 at the lower portion of the inside of the cylinder 50 to suppress the flow velocity of water entering the cylinder 50 from the lower end 50b, it is possible to prevent the water flowing into the cylinder 50 from lowering the force of the floating body 51 and forming a flow. Things happened on the road.

By the operator, the accident of the air supply source 40 is cancelled. When air is supplied to the air path 41 from the air supply source 40 again, air flows into the cylinder 50 from the upper end 50a side and the water pressure in the cylinder 50 decreases. The water surface in the cylinder 50 is lowered and the floating body 51 is separated from the abutting surface 560c. Since the check valve 5B is opened, the air that has passed through the air path 41 is supplied to the mixing section 32.

1‧‧‧ agency

30‧‧‧ keep the platform

300‧‧‧ Supply Department

300a‧‧‧ holding surface

301‧‧‧Frame

31‧‧‧ Link Road

32‧‧‧ Mixing Department

33‧‧‧ divergence

330‧‧‧Vacuum valve

39‧‧‧ Attraction Source

38‧‧‧ Water supply source

37‧‧‧Water path

371‧‧‧Water stop valve

372‧‧‧throttle valve

40‧‧‧Air supply source

41‧‧‧air path

41a‧‧‧One end of air path 41

41b‧‧‧ the other end of air path 41

42‧‧‧ Division

44‧‧‧Air valve

45‧‧‧throttle valve

46‧‧‧Air Supply Road

47‧‧‧Air Drive Department

5‧‧‧ Check valve of Embodiment 1

50‧‧‧ tube

The upper end of 50a‧‧‧ tube 50

50b‧‧‧ the lower end of the tube 50

50c‧‧‧ abutment

50d‧‧‧Water inlet

51‧‧‧ floating body

52‧‧‧ shelter

5A‧‧‧ Check valve of Embodiment 2

50e‧‧‧Water inlet

54‧‧‧ shelter

5B‧‧‧ Check valve of Embodiment 3

55‧‧‧1st sleeve

551‧‧‧ shelter

56‧‧‧Second sleeve

58A, B‧‧‧One-touch connector

FIG. 1 is a sectional view schematically showing an example of a mechanism provided with a check valve.

Fig. 2 (A) is a sectional view showing the check valve of the first embodiment formed in an open state. Fig. 2 (B) is a sectional view showing the check valve of the first embodiment formed in a closed state.

Fig. 3 (A) is a cross-sectional view showing a check valve of Embodiment 2 formed in an open state. Fig. 3 (B) is a cross-sectional view showing a check valve of the second embodiment formed in a closed state.

Fig. 4 (A) is an exploded perspective view showing a check valve according to the third embodiment. Fig. 4 (B) is a perspective view showing a check valve according to the third embodiment.

Fig. 5 is a perspective view showing a check valve of a third embodiment in a state where a one-touch joint is mounted.

Fig. 6 (A) is a cross-sectional view showing a check valve of Embodiment 3 formed in an open state. Fig. 6 (B) is a sectional view showing a check valve of a third embodiment formed in a closed state.

Claims (2)

A non-return valve is provided with a supply section that supplies a mixed fluid that mixes air and water; a mixing section that mixes air and water; a communication path that communicates the mixing section and the supply section; An air path that communicates with the air supply source; a water path that communicates the mixing part with the water supply source; and a branching portion arranged in the air path and communicates with an air drive unit that is driven by the air supply In the mechanism of the air supply path, a check valve is arranged between the mixing section and the branching section, and prevents water from flowing from the mixing section to the air driving section. The non-return valve is provided with a cylinder that stands vertically so as to communicate the lower end with the mixing portion and communicate the upper end with the air supply source; and a water surface floating on the water that enters the cylinder from the lower end and moves upward and downward. If the floating body is positioned at the upper end of the cylinder, the air path is blocked, and if the floating body is far from the upper end of the cylinder, air can be supplied to the mixing section. The non-return valve according to item 1 of the patent application, wherein the lower portion of the inside of the barrel is provided with a shielding portion that suppresses a flow rate of water entering the barrel from the lower end.