JP4292060B2 - Normally closed float auto drain - Google Patents

Description

The present invention relates to a normally closed float auto drain, and more particularly to a normally closed float auto drain that can be changed from a normally closed type to a normally open type.

  A pneumatic actuator such as a pneumatic cylinder is connected to a compressed air supply source such as a compressor by a pneumatic pipe. In general, air discharged from a compressor contains liquid components such as moisture and oil. In order to supply clean air from which these have been removed to pneumatic equipment, the pneumatic piping that makes up the pneumatic system automatically discharges liquid to the outside when a predetermined amount of liquid has accumulated in the container. Drain is used.

  The auto drain has a container in which an inlet and an outlet for compressed air are provided at the top and a drain hole is provided at the bottom, and the liquid separated from the compressed air flowing from the inlet to the outlet is stored in the container. Later, it is an automatic drain valve that automatically discharges, and is used in places where it is difficult to manually open and close, or where liquid is to be discharged at an appropriate timing. This auto drain has a float type that opens and closes the drain drain valve by the buoyancy of the float floating in the liquid.When the liquid is stored above the set water level, the drain drain valve is automatically opened and the liquid drain valve is opened. Drain.

  In addition to the above buoyancy, there is a type that uses the air pressure of compressed air or the biasing force of a spring as the opening / closing force of a drain drain valve. And normally closed auto drain.

  Normally open auto drains open the drain drain valve under the condition that compressed air is not supplied to the pneumatic system from the pneumatic source, and when compressed air enters the container when compressed air is supplied to the pneumatic system The drain drain valve is closed by pressure, and when the liquid accumulates in the container above the set water level, the drain drain valve is opened by the float. On the other hand, a normally closed auto drain keeps the drain drain valve closed even when compressed air is not supplied to the pneumatic system, and when the liquid accumulates above the set water level in the container, the drain drain valve Will be opened.

  The normally open auto drain is in a state where liquid is discharged from the container because the drain drain valve is always open when the pneumatic system is in a rest state without supplying compressed air. However, when the pneumatic system is started, the normally open auto drain cannot be closed unless compressed air is supplied until the inside of the container reaches a predetermined pressure. Therefore, a part of the compressed air leaks from the drain drain valve that is open in the initial state, and there is a problem that the pressure inside the container is difficult to increase depending on the flow rate of the compressed air.

  As an example of a float type auto drain classified into a normally open type and a normally closed type, Patent Documents 1 and 2 disclose that a drain drain valve opening / closing operation is determined by a resultant force of an urging force acting on a piston and an air pressure. Auto drains are disclosed. This technology is controlled by a pilot valve body that drives the flow of compressed air supplied into the bowl with the buoyancy of the float, using a piston that is urged in one direction with a compression coil spring as the valve body of the drain drain valve. Thus, the drain drain valve is opened and closed.

In this way, in the float type auto drain that uses the biasing force of the coil spring as the opening / closing force of the drain drain valve, it is known that the model can be changed to the normally open type or the normally closed type by changing the biasing direction. It has been. For example, in the above-mentioned Patent Documents 1 and 2, a normally closed spring that applies an upward biasing force to a piston and a normally open spring that applies a downward biasing force are prepared, and a normally closed type is obtained by selectively exchanging them. It can be changed to a normally open type.
Japanese Patent No. 3389319 Japanese Patent No. 3389304

  When changing the model from the normally open type to the normally closed type, or from the normally closed type to the normally open type, according to the method disclosed in the above-mentioned patent document, the operation of removing the installed coil spring and newly installing the coil spring Two steps of work are required and workability is inferior. In addition, the force acting in the valve closing direction when closing the normally open drain drain valve is only air pressure, and the force acting in the valve opening direction when opening the normally closed drain drain valve is only air pressure. is there. Therefore, it is necessary to secure the opening / closing force of the drain drain valve by supplying compressed air of a predetermined pressure or higher into the bowl or increasing the effective pressure receiving area of the piston, and it is mounted on an air compressor with a small capacity. It has become difficult.

An object of the present invention is to provide a normally-closed float type auto drain which can be changed to a normally-open type based on a normally-closed type.

Another object of the present invention is to provide a normally closed float type auto drain capable of switching to a normally open type with a small number of parts.

Another object of the present invention is to provide a normally closed float type auto drain which can be mounted on a pneumatic system with a low flow rate.

Normally-closed float type auto drain of the present invention, a container with inlet and outlet of the compressed air and the joint portion provided on the top, joint drainage holes are formed is attached to the joint portion Re et provided at the bottom A normally-closed float type auto drain that automatically discharges liquid separated from the compressed air flowing from the inlet to the outlet, and has an air inlet hole at the upper end, and the drain hole a support cylindrical body which is attached to the joint made to communicate with a cradle provided on the support tube inside passage is formed for communicating the drain hole and the float chamber in the container, sliding on the inner surface of the support cylinder A piston that detachably attaches a pressure chamber that communicates with the air inflow hole in the support cylinder, and a seal member that is provided integrally with the piston and provided at the position of the drain hole of the joint. A piston member having a closing portion for opening and closing said drain hole while touching, vertically movable disposed in the float chamber of the container, the air inflow hole opened by upward movement by accumulated liquid into the container A float that guides compressed air into the pressure chamber, and is mounted in the piston member so as to be positioned in the pressure chamber, and the opening / closing portion is normally biased to the piston member in a direction to open the drainage hole. Mounted in a normally closed spring accommodating portion formed between the piston member and the support cylinder, between the opening spring and a spring receiving member provided projecting outward of the piston member and the cradle. A normally closed spring that biases a biasing force larger than a biasing force of the normally open spring in a direction to close the drain hole with respect to the opening and closing portion, and the normally open spring and the normally closed spring Above When the normally closed spring is removed from the normally closed spring housing portion from the normally closed shape that urges the drain hole in the closing direction with respect to the closed portion, the open / close portion is drained when compressed air is not supplied into the float chamber. It is characterized in that it can be switched to a normally open type that opens a hole .

  The present invention can be configured as a normally open float type auto drain under the condition that the normally closed spring is not attached to the normally closed spring accommodating portion.

  In this invention, it can comprise as a normally closed type float type auto drain by mounting | wearing a normally closed spring accommodation part with a normally closed spring. If the attached normally closed spring is removed, it can be reconfigured as a normally open float auto drain.

  In the present invention, a normally open type or normally closed type auto drain can be configured by mounting or removing a normally closed spring, so that parts can be shared between the normally open type and the normally closed type. In addition to facilitating the management of parts, the manufacturing cost can be reduced.

  In the present invention, when changing from the normally open type to the normally closed type, or from the normally closed type to the normally open type, the model is changed with fewer man-hours than the prior art, which required two steps of removal work and assembly work. be able to.

  In the present invention, by using the air pressure and the biasing force of the spring as the operating force of the piston that opens and closes the drain hole, the piston diameter can be reduced and the piston can be mounted on a pneumatic system with a small flow rate. Compared to a float type auto drain that uses only the float buoyancy as the opening / closing force of the drain drain valve, it is possible to reduce the size of the piston and hence the size of the float, and it can also be mounted on a filter with a small capacity. .

Hereinafter, embodiments of the present invention will be described in detail with reference to the drawings. FIG. 1 is a partially cutaway front view showing the entire normally closed float type auto drain as an embodiment of the present invention, FIG. 2 is a cross-sectional view showing the main part of FIG. 1, and FIG. FIG. 4 is an explanatory view showing a state in which liquid is discharged from the normally closed float type auto drain shown in FIG. 1 and FIG. 2, and FIG. 4 is an explanatory view showing an enlarged state where a normally closed spring is not mounted.

As shown in FIG. 1, this normally closed float type auto drain 10 has a container 11 including a cylindrical case 1 with a bottom and a joint portion 2 fixed to an opening end portion on the upper end side thereof. The joint portion 2 is provided with an inlet 3 and an outlet 4 for compressed air. Pipes constituting a pneumatic system are connected to the inlet 3 and the outlet 4, respectively, and compressed air flowing into the container 11 from the inlet 3 is turned downward while turning by the louver 5. While flowing, it passes through the filter 6 provided in the joint portion 2 and flows out from the outlet 4 to the outside.

  The liquid swirled by the louver 5 and separated from the compressed air by the cyclone effect falls along the inner peripheral wall of the container 11 toward the float chamber 7 below the container 11. In order to prevent the separated drain from being rolled up, a baffle 8 is provided in the joint portion 2. A bowl guard 13 is attached to the outside of the container 11 for safety.

  As shown in FIG. 2, a joint 15 is fixed to a bottom portion of the container 11 with a retaining ring 14, and a drain hole 12 communicating with the float chamber 7 is formed in the joint 15. A drain tube is connected to the joint 15.

  A support cylinder 16 is attached to the inner bottom portion of the container 11 so as to communicate with the drain hole 12. The support cylinder 16 has a lower large-diameter portion 16a and an upper small-diameter portion 16c integrated with the large-diameter portion 16a via a flange portion 16b, and a partition wall portion 16d is provided at the upper end. It has been. A part of the large-diameter portion 16a is formed with a screen-like screen 17 that communicates the inside and the outside, and an air inflow hole 18 is formed in the partition wall portion 16d. A disk-shaped plate 19 is slidably contacted with the support cylinder 16 on the small diameter portion 16c so as to be movable up and down, and a hollow float 20 is mounted on the plate 19 so as to surround the support cylinder 16. . The float 20 moves up and down in conjunction with the water level of the liquid accumulated in the float chamber 7. In order to prevent the float 20 from detaching from the support cylinder 16 or colliding with the baffle 8 or the like, the partition wall portion 16d has a larger diameter than the small diameter portion 16c, and the plate 19 collides with the float 19 so as to float. 20 upper limit positions are regulated.

  A piston member 21 and a cradle 22 are accommodated in the support cylinder 16. The piston member 21 is slidably mounted inside the support cylinder 16 and divides the inside of the support cylinder 16 into an upper pressure chamber 23 and a lower drainage chamber 24, and the piston 21a is integrated with the piston 21a. An opening / closing portion 21b that opens and closes the drain hole 12, and a spring receiving portion 21c that protrudes from the lower side of the piston 21a. A piston packing 25 is incorporated in the piston 21 a, and the piston packing 25 seals between the piston 21 a and the inner surface of the support cylinder 16. An O-ring 26 is incorporated at a position where the drainage hole 12 of the joint 15 is formed. When the piston member 21 is at the upper limit position, the drainage hole 12 is sealed together with the opening / closing part 21b so that the liquid is not discharged. ing. The piston member 21 is formed with a small-diameter bleed hole 34, and the pressure chamber 23 communicates with the outside through the bleed hole 34. When the compressed air flowing into the pressure chamber 23 contains some water or oil, a filter 35 is accommodated inside the piston member 21 to collect these.

  The cradle 22 is formed with a passage 27 that opens to the screen 17 and communicates the float chamber 7 and the drainage chamber 24. When compressed air is supplied into the container 11, the compressed air flows from the screen 17 into the drainage chamber 24 and acts as a force that pushes the piston member 21 upward. On the other hand, the pressure chamber 23 communicates with the float chamber 7 through the air inflow hole 18. When compressed air flows into the pressure chamber 23 through the air inflow hole 18, the pressure chamber 23 has a force to push the piston member 21 downward. Will work. Further, a spring receiving portion 22a is provided at a position facing the spring receiving portion 21c of the receiving base 22, and a normally closed spring accommodating portion 28 is formed between the spring receiving portion 21c and the spring receiving portion 22a.

  An upper lid 29 is incorporated in the upper part of the float 20 so as to cover the support cylinder 16. The upper lid 29 is assembled between the plate 19 and the retaining ring 30 using a retaining ring 30 and moves up and down integrally with the float 20. A support portion 29b protrudes from the ceiling portion 29a of the upper lid 29 toward the air inflow hole 18, and an annular pressing plate 31 is fixed to the side surface portion 29c. A plate-like vane 32 having a connecting portion 32a sandwiched between the presser plates 31 and an opening / closing portion 32b extending in continuity with the connecting portion 32a is provided inside the upper lid 29. A vane valve that opens and closes 18 is formed. Therefore, as shown in FIG. 3, when a liquid having a predetermined water level or more accumulates in the container 11, the float 20 moves upward, and the vane 32 elastically deforms accordingly, opens the air inflow hole 18 and opens the pressure chamber 23. The compressed air is guided inside.

  A normally open spring 33 is mounted in the pressure chamber 23 in a slightly compressed state from its natural length. By this normally open spring 33, the piston member 21 is pushed downward, that is, the opening / closing portion 21b is It is urged to open the drain hole 12. Therefore, when the normally closed spring 36 is not attached to the normally closed spring accommodating portion 28 and the compressed air is not supplied into the float chamber 7, the opening / closing portion 21b opens the drain hole 12, that is, normally opened. It can be configured as a floating auto drain 10 of the shape.

  The normally open float type auto drain 10 is provided with a normally closed spring 36 in a compressed state in the normally closed spring accommodating portion 28 so that the open / close portion 21b is drained when compressed air is not supplied into the float chamber 7. The hole 12 can be closed, that is, it can be configured as a normally closed float type auto drain 10. At this time, the spring constant of the normally closed spring 36 and the amount of deformation at the time of incorporation are set so that the normally open spring 33 applies an upward biasing force larger than the biasing force for lowering the piston member 21.

  The effective pressure receiving area of the piston member 21 on the drainage chamber 24 side is such that the operating force for raising the piston member 21 of the compressed air flowing into the drainage chamber 24 is larger than the actuation force for the normally open spring 33 to lower the piston. Is set. Further, the effective pressure receiving area of the piston member 21 on the pressure chamber 23 side is determined by the resultant force of the air pressure of the compressed air flowing into the drainage chamber 24 and the biasing force of the normally open spring 33 and the normally closed spring 36. The operating force for lowering the piston member 21 of the compressed air that has flowed into the pressure chamber 23 is set to be larger than the operating force for increasing the pressure. Thus, by using the air pressure and the biasing force of the spring as the operating force of the piston member 21 that opens and closes the drainage hole 12, the piston diameter can be reduced and the piston can be used for an air compressor having a small capacity. Compared to a float type auto drain that uses only the float buoyancy as the opening and closing force of the drain discharge valve, it is possible to reduce the size of the piston and hence the size of the float. Can do.

Next, the operation of the normally closed float type auto drain 10 having the above configuration will be described. First, in the state where the normally closed spring 36 is not mounted as shown in FIG. 4, if compressed air is not supplied into the container 11, the pressure in the pressure chamber 23 is external to the container 11 through the bleed hole 34. The pressure is the same as the pressure. At this time, since no pressure is applied to the drainage chamber 24, the piston member 21 is moved downward by the downward biasing force of the normally open spring 33, and the opening / closing part 21 b opens the drainage hole 12. In the case shown in FIG. 4, in order to express the movement of the piston member 21 in an easy-to-understand manner, the piston member 21 is moved downward larger than the actual movement amount.

  On the other hand, when the compressed air is supplied into the container 11 and the liquid accumulated in the container 11 is below a predetermined water level, the compressed air that has flowed into the drainage chamber 24 causes the piston member 21 to flow. When the piston member 21 is pushed upward and the piston member 21 is raised, the opening / closing part 21b closes the drain hole 12. Under this state, when the liquid accumulated in the float chamber 7 in the container 11 reaches a predetermined water level or higher, the float 20 rises to open the air inflow hole 18 and guide the compressed air into the pressure chamber 23. . The compressed air that has flowed into the pressure chamber 23 presses the piston member 21 downward, and when the piston descends, the opening / closing portion 21b opens the drain hole 12. That is, the float type auto drain 10 operates as a normally open type auto drain.

  Next, the operation when the normally closed spring 36 is attached to the float type auto drain 10 will be described. First, as shown in FIG. 2, when compressed air is not supplied into the container 11, the piston member 21 is pushed up to a position where the drain hole 12 is closed by the resultant force of the normally open spring 33 and the normally closed spring 36. . Thereby, the drain hole 12 is sealed by the opening / closing part 21b of the piston member 21 and the O-ring 26 engaged therewith, and the compressed air in the container 11 is prevented from flowing out of the joint 15 to the outside.

  On the other hand, when the compressed air is supplied into the container 11 and the liquid accumulated in the container 11 is below a predetermined water level, the compressed air flows into the drainage chamber 24 via the passage 27. Then, the piston member 21 is pressed upward. That is, in addition to the biasing force of the normally open spring 33 and the normally closed spring 36, the air pressure of the compressed air that has flowed into the drain chamber 24 acts on the piston member 21 as a force in the direction of closing the drain hole 12.

  Under this state, when the liquid accumulated in the float chamber 7 in the container 11 reaches a predetermined water level or more, as shown in FIG. 3, the float 20 rises by buoyancy, and the vane 32 enters the air inflow hole 18. It is elastically deformed in the opening direction, and the compressed air in the container 11 flows into the pressure chamber 23 through the air inflow hole 18. The compressed air flowing into the pressure chamber 23 presses the piston member 21 downward. At this time, the air pressure of the compressed air that has flowed into the drainage chamber 24 and the normally open spring 33 and the normally closed spring 36 are added. Since the resultant force is greater than the resultant force, the piston member 21 operates downward, that is, in the direction of opening the drain hole 12, and the liquid in the drain chamber 24 is discharged through the drain hole 12.

  When the liquid is discharged to a predetermined water level and the float 20 descends, the vane 32 closes the air inflow hole 18 and compressed air is not supplied to the pressure chamber 23. When the compressed air in the pressure chamber 23 is discharged to the outside through the bleed hole 34, the pressure in the pressure chamber 23 decreases, and the drain hole 12 is closed by the piston member 21 moving up again. . That is, by mounting the normally closed spring 36, the float type auto drain 10 can be operated as a normally closed type auto drain.

  It is also possible to operate as a normally open float type auto drain 10 by removing the attached normally closed spring 36 again. In this way, when changing the model from the normally open type to the normally closed type, it is only necessary to perform the work of mounting the normally closed spring 36, and when changing the model from the normally closed type to the normally open type, the normally closed spring 36 is removed. Since it is only necessary to perform the work, the number of work steps can be reduced as compared with the conventional technique that always requires two steps of removal work and attachment work when changing the model.

  It goes without saying that the present invention is not limited to the above-described embodiment, and various modifications can be made without departing from the scope of the invention.

BRIEF DESCRIPTION OF THE DRAWINGS FIG. 1 is a partially cutaway front view showing an entire normally closed float type auto drain according to an embodiment of the present invention. It is sectional drawing which shows the principal part of FIG. It is explanatory drawing which shows the state from which the liquid is discharged | emitted from the normally closed type float type auto drain shown in FIG. 1 and FIG. It is explanatory drawing which expands and shows the state which is not mounting | wearing with a normally closed spring.

Explanation of symbols

7 Float chamber 10 Float type auto drain 11 Container 12 Drain hole 16 Support cylinder 17 Screen 18 Air inflow hole 20 Float 21 Piston member 21a Piston 21b Open / close part 23 Pressure chamber 24 Drain chamber 32 Vane 33 Normally open spring 34 Bleed hole 36 Normal Closing spring

Claims (1)

With inlet compressed air and the outlet port and the joint portion provided on the top, joint drainage hole is formed and a container attached to the provided et Re the joint portion in the bottom portion, the outlet from the inlet A normally closed float type auto drain that automatically discharges the liquid separated from the compressed air flowing through
An air inflow hole is formed at the upper end, and a support cylinder that is attached to the joint in communication with the drain hole;
A cradle provided in the support cylinder in which a passage communicating the float chamber in the container and the drain hole is formed;
A piston slidably mounted on the inner surface of the support cylinder and defining a pressure chamber communicating with the air inflow hole in the support cylinder, and provided at the position of the drain hole of the joint provided integrally with the piston A piston member that has an opening and closing portion that contacts the sealed member and opens and closes the drain hole;
A float for guiding the is vertically movable disposed in the float chamber, the compressed air to the pressure chamber by opening the air inlet hole by the rising movement by accumulated liquid into the container of the container,
A normally open spring that is mounted inside the piston member so as to be positioned in the pressure chamber, and that biases the opening / closing portion in a direction to open the drain hole with respect to the piston member;
Mounted in a normally closed spring accommodating portion formed between the piston receiving member and the support cylinder, between the spring receiving member provided projecting outward from the piston member and the receiving base. A normally closed spring that biases a biasing force larger than a biasing force of the opening spring in a direction to close the drain hole with respect to the opening and closing part;
The normally closed spring is removed from the normally closed spring housing portion and compressed into the float chamber from a normally closed type in which the normally open spring and the normally closed spring urge the opening / closing portion in a direction to close the drain hole. A normally closed float type auto drain characterized in that the open / close portion can be switched to a normally open type that opens the drainage hole when air is not supplied .

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