JPS6125951B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention supplies liquid from a liquid supply source to a liquid tank, automatically stops the liquid supply when the liquid in the liquid tank reaches a preset liquid level, and further includes: A liquid with a liquid level maintenance function that automatically starts liquid supply from the liquid supply source when the device is removed from the liquid level or when the liquid level drops due to supply of liquid in the liquid tank to the outside. The surface control device is related.

Conventionally, this type of liquid level control device generally includes a liquid level detection device for detecting the liquid level, and a control for amplifying and output converting the liquid level detection fine input signal from the detection device. It is configured as a series of system devices by combining devices, control valves, etc. for switching the supply of liquid.

A typical example of a simple liquid level control device that combines the above functions is an opening/closing device equipped with a detection float mechanism and a mechanical mechanism for detecting the liquid level used in flush toilet equipment, aquarium tanks, etc. One option is to combine it with a valve, but in this case, the detection float mechanism is generally large and requires a relatively large installation space, which limits the places where the liquid level control device can be used. Since the installation of this device must also be fixed in relation to the liquid tank, there is a control to separate the liquid tank and the liquid level control device, and therefore, this liquid level control device cannot be used as a mobile device. It's inappropriate.

Furthermore, when a series of system devices are combined into a unit or a panel device for a liquid level control device, there is a drawback that the system as a whole not only becomes large-scale, but also complicated and expensive.

An object of the present invention is to provide a liquid level control device that has a simple structure, is compact, has low production costs, and can perform reliable and stable liquid level control, thereby eliminating the above-mentioned drawbacks of the conventional art. There is a particular thing.

Next, the configuration of an embodiment of the present invention is shown in FIGS. 1 to 3.
This will be explained using figures.

A liquid level control device 5 that combines four blocks 1 to 4 includes a liquid inlet 7 formed on the side surface of the main body 6 and a liquid outlet 10 formed on the bottom surface of the recess 9 of the cylindrical liquid level detection tube 8 on the lower surface of the main body 6. In the middle of the liquid flow path 11 formed between the The liquid flow path 11 is closed by the reverse operation of the diaphragm 14 (the state shown in FIG. 3), and the restoring operation of the diaphragm 14 is performed by the pressure reduction in the pilot chamber 15 (the state shown in FIG. 1).
The main on-off valve 12 that opens the liquid flow path 11 is formed by the state shown in FIG. 2).

A valve seat 17 is formed protruding in the valve chamber 16 of the main on-off valve 12 so as to come into contact with the center of the diaphragm 14 when the diaphragm 14 is reversed. Therefore, even if the pressure in the pilot chamber 15 is considerably lower than the liquid supply pressure when the valve is open and the liquid is flowing, the diaphragm 14 can operate in reverse.
The pilot passage 19 communicates with a gas pressure source 22 through a fixed orifice 23 through a gas pressure inlet 20 and a main stock 21.

On the other hand, this pilot passage 19 is connected to a pilot control valve 24, in this case a diaphragm chamber 25 which is partitioned into two chambers, a pressure receiving chamber 27, by a diaphragm 26, and when the pressure in the pressure receiving chamber 27 increases, the diaphragm 26 is reversed (the state shown in FIG. 3). Yotsute diaphragm 2
A valve seat 40 is formed at a position where it abuts the center part of 6.
The pilot passage 19 is closed by blocking the pressure receiving chamber 2.
When the diaphragm 26 is restored due to the decrease in pressure at step 7 (the state shown in FIGS. 1 and 2), the pilot passage 19 is opened via the pilot control valve 24 and the air bleed 29 which also serves as a drain, which communicates with the atmosphere. The pressure receiving chamber 27 of the pilot control valve 24 communicates with the pilot passage 19 via a fixed orifice 30, and also communicates with the recess 9 of the liquid level detection tube 8 via the pilot passage 31 at its bottom surface.

In addition, 32 and 33 are seal rings for holding down each diaphragm 14 and 26, 34 is a blind stopper, and 35 is connected to the liquid inlet 7 of the liquid level control device 5 via a main cock 36 for opening and closing the liquid flow passage 11, which is manually or remotely controlled. Indicates a liquid supply source, such as a connected water supply or hydraulic tank.

Next, the operation of this embodiment will be explained with reference to FIGS. 2 and 3.

When supplying the liquid from the liquid supply source 35 to the liquid tank 37 and maintaining the liquid in the liquid tank 37 at a preset liquid level, the liquid level detection tube 8 of the liquid level control device 5
The liquid level control device 5 is attached to the liquid tank 37 in a state where the liquid level is adjusted to the preset liquid level position in the liquid tank 37.

When the main cock 21 for the gas pressure source 22 is opened in this installed state, the pressure receiving chamber 27 of the pilot control valve 24 is open to the atmosphere because the recess 9 of the liquid level detection tube 8 is open to the atmosphere. Since the pilot passage 19 is also opened through the air vent 29 of the valve chamber 28 of the pilot control valve 24, the main on-off valve 12 is also in an open state.

Therefore, when the main cock 36 for the liquid supply source 35 is opened with each of the valves 12 and 24 open, the liquid from the liquid supply source 35 flows into the liquid flow path 1 as shown in FIG.
1 is supplied to the liquid tank 37 through the main on-off valve 12, where the outflow path 38 of the main on-off valve 12 is connected to the inflow path 3.
9, the effective cross-sectional area of the passage is increased to reduce the liquid pressure in the outflow passage 38 to near atmospheric pressure, so the liquid pressure acts on the diaphragm 14 only near the valve hole 18 at the center of the diaphragm 14, and the liquid Liquid from supply source 35 flows through main on-off valve 12 to liquid tank 37 .

As the liquid is supplied to the liquid tank 37 in this way, the liquid level in the liquid tank 37 gradually rises, and when the liquid level reaches the lower surface of the liquid level detection tube 8, it further rises and the pilot The air pressure inside the pressure receiving chamber 27 of the control valve 24 increases while being balanced with the liquid pressure, and the diaphragm 26 is reversed due to the difference in pressure received by the diaphragm 26 from the pressure receiving chamber 27 and the valve chamber 28, and pilot control is performed. As the valve 24 closes and the pressure inside the pilot chamber 15 of the main opening/closing valve 12 increases, the diaphragm 14 operates in reverse due to the difference in pressure receiving area between the effective sealing area of the valve hole 18 and the effective area of the diaphragm 14. When the main on-off valve 12 closes, the supply of liquid from the liquid supply source 35 to the liquid tank 37 is stopped.

Next, while this liquid level is maintained and the liquid supply is stopped, the liquid in the liquid tank 37 is supplied to the outside, and when the liquid level in the liquid tank 37 falls below a preset liquid level, the pressure received by the pilot control valve 24 is reduced. When the air pressure in the chamber 27 drops to a constant pressure, the diaphragm 26 operates to restore and the pilot control valve 24 opens, and the pressure in the pilot chamber 15 of the main opening/closing valve 12 is also released, so the diaphragm 14 operates to restore and the pilot control valve 24 opens. Open/close valve 1
2 opens.

As a result, liquid is supplied to the liquid tank 37 again from the liquid supply source 35, and when the liquid level in the liquid tank 37 reaches the preset liquid level, the main on-off valve 12 closes as described above. The above operation is repeated again in a state where the supply of liquid is stopped and the liquid level has fallen below a predetermined position taking into consideration the hysteresis characteristics, and the liquid level of the liquid in the liquid tank 37 is reduced to the level of the liquid in the liquid tank 37. It can be maintained almost constant regardless of whether it is supplied to the outside.

In addition, the diaphragms 14 and 26 of each valve 12 and 24
As shown in Fig. 3, during pressure receiving operation, the valve chamber 1
The diaphragms 14, 26 are hollowly supported in local contact with the valve seats 17, 40 that protrude inside the valve seats 6, 28, and the material of the diaphragms 14, 26 has the flexibility to bend in response to minute pressure, and also suppresses the elongation along the surface to below a certain value. By combining thin film materials, it is possible to secure a sufficient effective pressure receiving area for force conversion without a pressure receiving plate, and
The valve seats 17 and 40 face inclination and eccentricity can be adequately sealed. Furthermore, the diaphragms 14, 2
Since the bending and wrinkles of the material 6 are absorbed by the hollow portion, the seals of the valve seats 17 and 40 are always maintained reliably when the diaphragms 14 and 26 are reversed. The material for the diaphragms 14, 26 is selected depending on the conditions of use, and examples thereof include thin rubber plates or leather containing fibers or thin resin threads in a mesh or radial pattern, resin films (thin plates), and the like.

Based on the above characteristics, the diaphragm 26 of the pilot control valve 24 for liquid level detection has its surface oriented perpendicular to the horizontal plane of gravity, thereby preventing the influence of the own weight of the diaphragm 26 itself. .

Next, FIG. 4 shows a liquid level control device 5' according to another embodiment of the present invention, in which a diaphragm-operated pilot control valve for controlling opening and closing of communication with the atmosphere is provided in the upper part of the liquid level detection tube 8'. In this case, when there is no liquid in the liquid tank 37, the pilot control valve 24 is open because its pressure receiving chamber 27 is open to the atmosphere, and the main on-off valve 12 is also open. Even if liquid is supplied to the liquid tank 37 through the main on-off valve 12, the liquid pressure in the valve chamber 16 of the main on-off valve 12 is low, so the pilot control valve 41 remains open and the liquid level in the liquid tank 37 is at the lowest level. Even beyond the L1 position in Fig. 4, the liquid level rises further because the recess 9' of the liquid level detection tube 8' communicates with the atmosphere through the air bleed 42 of the pilot control valve 41, and the liquid level rises further. When reaching the L2 position in Figure 4, where communication between 9' and the atmosphere is blocked,
The main on-off valve 12 closes together with the pilot control valve 24 to stop the supply of liquid, and the pilot control valve 41 also closes due to the increased hydraulic pressure caused by this stop.

As a result, even if the liquid in the liquid tank 37 is supplied to the outside and the liquid level in the liquid tank 37 becomes below L2 in FIG. The on-off valve 12 is also kept closed, and the main on-off valve 12 is opened together with the pilot control valve 24 when the liquid level falls below L1 in FIG. The liquid is supplied to the liquid tank 37, and the pilot control valve 41 is opened due to the drop in liquid pressure caused by this liquid supply, and the same operation as described above is repeated again, and the liquid level reaches the L2 position in Fig. 4. At this point, the liquid supply is stopped.

As described above, the present invention allows the level position of the liquid supplied from the liquid supply source to the liquid tank to be easily maintained constant by a liquid level control device independent from the liquid tank, and furthermore, This has the advantage that the entire liquid level control device can be made smaller, and the space required for installing the device can be significantly reduced compared to conventional mechanical control.

[Brief explanation of the drawing]

FIG. 1 is a cutaway front view of one embodiment of the present invention, and FIG.
3 and 3 are explanatory diagrams showing the state of use thereof, and FIG. 4 is a sectional front view of another embodiment of the present invention. 5...Liquid level control device, 8...Liquid level detection tube, 11
...Liquid flow path, 12...Main on-off valve, 19, 31
... Pilot passage, 24 ... Pilot control valve, 35 ... Liquid supply source, 37 ... Liquid tank.

Claims (1)

[Claims] 1. A diaphragm partitions the diaphragm chamber into a pilot chamber and a valve chamber, and a valve hole is formed at a position facing the center of the diaphragm of the valve chamber, in the middle of a liquid flow path that supplies liquid from a liquid supply source to a liquid tank. A pilot passage which connects a gas pressure source to the atmosphere is provided with a main opening/closing valve that forms a valve seat and closes the valve by contact between the diaphragm and the valve seat due to the reversal action of the diaphragm as the pressure in the pilot chamber increases. On the way, the diaphragm divides the diaphragm chamber into a pressure receiving chamber and a valve chamber, and a valve seat with a valve hole is formed at a position facing the center of the diaphragm in the valve chamber, and the pressure in the pressure receiving chamber increases. A pilot control valve is provided which closes the valve by the contact between the diaphragm and the valve seat due to the reversal action of the pilot control valve, and the inflow side pilot passage of the pilot control valve is communicated with the pressure receiving chamber of the pilot control valve and the pilot chamber of the main opening/closing valve. Furthermore, when the liquid level detection cylinder communicating with the pressure receiving chamber of the pilot control valve contacts the liquid level in the liquid tank or is immersed in the liquid, the pressure increases in accordance with the height of the liquid level in the liquid tank in the pressure receiving chamber. Therefore, the diaphragm of the pilot control valve is actuated in reverse to close the pilot passage, and the diaphragm of the main opening/closing valve is opened by increasing the pressure corresponding to the gas pressure source in the pilot chamber of the main opening/closing valve due to the closing of the pilot passage. A liquid level control device characterized in that the liquid flow path is closed by reverse operation.