JPS6147317B2 - - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION [Field of Industrial Application] The present invention relates to an automatic air supply device for a pressure tank used in a water supply system.

[Prior art] Pressure tanks for water supply systems have built-in compressed air to pressurize the water supplied from the faucet, but this air is dissolved in water and flows out to the outside, so it must be replenished in a timely manner. There is a need to. Various means have been proposed or put into practical use for automatically replenishing air in conjunction with pump operation.

[Problems to be Solved by the Invention] However, conventional means have been unable to solve problems such as malfunction of valves due to dirt, etc., failure of pumps to pump water due to air intake, problems such as excessive or insufficient air supply, and valve malfunction. Water hammer and the like are likely to occur at times, and if these drawbacks are to be eliminated, the device will inevitably become more complicated and the cost will increase.

The present invention was made based on the above circumstances, and
The purpose is to provide an automatic air replenishment device for a pressure tank for water supply that has a simple structure, is highly reliable, can be applied to both suction and push operation modes, and is less likely to cause water hammer. There is a particular thing.

[Means for Solving the Problems] The present invention has a partition wall such as a piston or bellofram that is pressurized upward and can be freely displaced in the vertical direction, and a lower chamber partitioned by the partition wall is a part of the pump. A supply part casing connected to the suction side and an inlet opening tangentially to the peripheral wall of the volute chamber communicate with the pressure tank, and an outlet opening axially in the center of the volute chamber. A spiral fluid diode communicating with an upper chamber partitioned by a partition wall of the supply section casing, and an intake valve having one end connected to the other end of an intake pipe opening in the center of the spiral chamber. It is characterized by what it did.

[Function] According to the present invention, at the start of pump operation, the lower chamber of the casing becomes negative pressure and the piston is moved downward, which causes air to be sucked into the volute chamber through the intake valve, and when the pump is stopped, When the piston is returned upward, the air is forced out into the pressure tank, effectively providing automatic air replenishment.

[Embodiments of the Invention] The present invention will be described below with reference to illustrated embodiments. In the first embodiment shown in FIG. 1, a water tank 1 is connected to the suction side of a pump 4 via a suction pipe 3 having a suction check valve 2. In the first embodiment shown in FIG. The discharge side of the pump 4 is connected to a pressure tank 8 via a discharge pipe 7 having a discharge check valve 5 and a gate valve 6 . The water in the pressure tank 8 is pushed by the compressed air in the tank and is supplied through the faucet 9. In addition, pressure tank 8
is provided with a pressure switch or a level switch (not shown), and is configured to be able to control on-off of the pump 4 in response to the pressure in the tank 8, etc.

As shown in FIGS. 2 and 3, the automatic air supply device 10 has a lower end connected to the suction check valve 2 and the pump 4.
Replenishment part 11 connected to suction pipe 3 between
and the upper end of this supply section 11 and the pressure tank 8.
a eddy current fluidic diode 12 connected between
A check-type intake valve 13 is provided which communicates with the center of the vortex chamber 28 of the fluid diode 12. Incidentally, instead of providing the replenishing section 11 and the fluid diode 12 integrally as shown in the figure, they may be connected through a suitable conduit.

As shown in FIG. 2, the replenishment section 11 includes a cylindrical casing 14, and an upper lid 15 and a lower lid 16 that are fluid-tightly attached to both upper and lower ends of the casing 14, respectively. The casing 14 houses a piston 17 that is slidably slidable in the vertical direction, and a compression coil spring 18 that is interposed between the piston 17 and the lower lid 16 and biases the piston 17 upward. There is. The piston 17 is located opposite to the inner periphery of stoppers 17a and 17b extending in both upward and downward directions and a lower stopper 17b, and has a leg portion 1 extending downward from the lower end of the lower stopper 17b.
7c. The lower chamber 19 formed below the piston 17 communicates with the suction pipe 3 via the conduit 20 as described above. A narrow gap is provided between the inner peripheral wall of the casing and the outer peripheral wall of the piston 17. The upper lid 15 also includes a vertical through hole 22 opened approximately in the center, and an inverted funnel-shaped recess 23 formed on the lower surface in communication with the through hole 22. A splitter 24 facing the recess 23 is attached to the upper lid 15 via a support member 25.

One end of an intake pipe 26 freely passes through the through hole 22 and projects upward, and an intake port 27 is provided at the projecting end of the intake pipe 26. The other end of the intake pipe 26 liquid-tightly penetrates the side wall of the casing 14 and extends to the outside, and the intake valve 13 is connected to this outer end. Intake valve 1
3 is preferably one that opens with as little negative pressure as possible and closes with as little positive pressure as possible, but with something configured like this, the operation tends to become unstable depending on the posture, so
According to experiments conducted by the inventors, it is preferable to arrange the opening on the atmosphere side so as to point vertically downward, thereby stably increasing the amount of air replenishment.

The fluid diode 12 shown in detail in FIG. 3 is integrally formed at the upper end of the upper lid 15. As shown in FIG.
This fluidic diode 12 includes a swirl chamber 28 having a circular cross section substantially concentric with the through hole 22, and a tangential inlet 29 opening in the peripheral wall of the swirl chamber 28.
and a through hole 22 as the axial outlet, which has a large resistance to flow in the direction of the inlet 29 → swirl chamber 28 → through hole 22, and has a large resistance to flow in the opposite direction. is configured so that it is small. A supply pipe 30 is connected to the inlet 29, and the supply pipe 30 opens into the pressure tank 8 at a reference level Lo thereof.

Next, the operation of the apparatus configured as described above will be explained. When the pump 4 is in a stopped state, the pressure is in equilibrium through the narrow gap between the inner circumferential wall of the casing 14 and the outer circumferential wall of the piston 17. It is located at the upper position shown in FIG.

When the pump 4 is started in this state, water flows from the water tank 1 into the pressure tank 8 via the suction check valve 2, suction pipe 3, pump 4, discharge pipe 7, check valve 5, gate valve 6, etc. Press-fitted. In this case, since the internal pressure of the suction pipe 3 decreases, the internal pressure of the lower chamber 19 also decreases,
On the other hand, since the upper chamber 21 has a high pressure almost equal to the internal pressure of the pressure tank 8, the piston 17
It descends against the restoring force of the coil spring 18, thereby increasing the internal volume of the upper chamber 21. If the amount of air in the pressure tank 8 is insufficient, the water level has risen above the reference level Lo, and the water in the pressure tank 8 flows to the supply pipe 30, The fluid flows into the upper chamber 21 via the fluid diode 12, the through hole 22, and the like. In this case, water flows tangentially into the vortex chamber 28 from the inlet 29, creating a vortex within the vortex chamber 28,
As illustrated in FIG. 4, a negative pressure portion is generated near the center of the swirl chamber 28. Therefore, air is drawn into the swirl chamber 28 from the intake valve 13 through the intake pipe 26, and this air is drawn into the upper chamber 21 through the through hole 22 together with water. Note that the vortex flow as described above promotes the separation effect between water and intake air.

When the pump 4 shifts from the transient state immediately after startup to the steady operating state and the piston 17 reaches the lower limit position, the internal pressure drop in the upper chamber 21 is eliminated, and the vortex chamber 2
Since the amount of water passing through 8 is reduced and the pressure drop at the center is also reduced, air intake from intake valve 13 stops. In the swirl chamber 28 and the upper chamber 21, the water and air continue to swirl for a while due to inertia, but eventually stop, and the air in the upper chamber moves to the swirl chamber 28 through the through hole 22. At this time, the concave portion 23 effectively moves air bubbles into the swirl chamber 28.
guided by. The above-mentioned state is maintained while the pump 4 is in a steady operating state. In this case, the leg portion 17c of the piston 17 and the lower lid 16 are in a liquid-tight state between the conduit 20 side and the supply section 11 side.

When the internal pressure or water level of the pressure tank 8 reaches a predetermined value and the operation of the pump is stopped, the upper chamber 21 and the lower chamber 19 are pumped through the narrow gap between the casing 14 and the piston 17, as in the initial state.
The internal pressures on the outer peripheral side of the piston leg portion 17c are in equilibrium, and the piston 17 is raised by the restoring force of the coil spring 18. As a result, air bubbles staying above the upper chamber 21 are forced into the swirl chamber 28 through the through hole 22 and into the pressure tank 8 through the supply pipe 30. In this case, since the flow in the fluid diode 12 is in the direction of low resistance, the air bubbles move toward the pressure tank 8 in a relatively short time.

The compressed air in the pressure tank 8 will generally not increase even if it is consumed, but if the amount of air is too large, the water level will drop to the reference level Lo.
In the event that the water has dropped below 100 mL, when the pump 4 is started, air or a mixed fluid of air and water flows from the tank 8 through the supply pipe 30 to the fluid diode 12.
is flowing into the country. In this case, a gas or gas-liquid two-phase vortex is generated in the vortex chamber 28, but the energy of the vortex is small and the pressure drop at the center is small, so that no air is sucked in from the intake valve 13. Therefore, no additional air is supplied to the pressure tank 8.

The amount of air replenishment is determined by the internal volume of the replenishment part 11 related to the stroke of the piston 17 and the fluid diode 12.
It is adjusted by appropriately setting the inflow amount or inflow pressure of water.

Note that by providing the splitter 24, air is efficiently carried as bubbles on the vortex flow of water flowing into the upper chamber 21 from the through hole 22, and is caused to flow around the outer periphery of the upper chamber 21, and air bubbles are formed in the center. Since water containing no water is continuously supplied, flow inhibition such as the so-called aerodynamic phenomenon can be eliminated, and a strong negative pressure can be continuously generated to improve the effectiveness of the pumping action. Further, by providing the splitter 24, when the flow of water in the upper chamber 21 weakens and eventually stops, the funnel-shaped recess 23
This effectively directs the air bubbles into the swirl chamber 28.

FIG. 5 illustrates the state of pressure fluctuation in each part, and FIG. 5A shows the inlet 29 of the fluid diode 12,
B is the actual pressure measurement value at the intake port 27, and C is the actual pressure measurement value at the through hole 22. T ₀ on the common time axis,
T ₂ indicates the time when the power to the pump 4 is turned on, T indicates the start point of steady operation of the pump, and T ₁ indicates the time when the same is shut off.

Note that although the case of pushing operation has been described above, substantially the same operation as described above is performed also in the case of suction operation.

According to the above configuration, an appropriate amount of air is fully automatically supplied depending on whether the pump 4 is turned on or off. In addition, since it is sufficient to provide the replenishment section 11, fluid diode 12, intake valve 13, etc., each of which has a simple structure and high durability, the replenishment device 10 as a whole has a simple structure, can be manufactured at low cost, and has excellent reliability. There is no need for maintenance. Furthermore, as shown in FIG. 5, there are few abnormal pressure fluctuations when the pump 4 starts and stops.
No water hammer phenomenon occurs.

In the second embodiment of the present invention shown in FIG. 6, a bellofram 31 is provided in place of the piston 17, and a bypass is provided in place of the discharge check valve 5 to allow a slight flow of water at all times. A discharge check valve 32 is provided. The rest of the structure is substantially the same as that of the first embodiment, so corresponding parts are denoted by the same symbols and the explanation thereof will be omitted. It goes without saying that this second embodiment also provides substantially the same effects as the first embodiment.

[Effects of the Invention] As described above, the present invention includes a replenishment part casing which is displaceable in the vertical direction and has a partition wall which is pressed upward, and whose lower chamber is connected to the suction side of the pump, and an inlet. a vortex type fluid diode whose outlet is communicated with a pressure tank and whose outlet is communicated with an upper chamber of the casing, and an intake valve which communicates with the center of the vortex chamber; and fluid diode both have simple structures and excellent reliability.
Further, it can be applied to both suction and push operation modes, and does not cause the water hammer phenomenon.

[Brief explanation of the drawing]

Figure 1 is a system diagram showing one embodiment of the present invention, Figure 2 is a system diagram showing an embodiment of the present invention.
The figure is a cross-sectional view of the main part, Figure 3 is a cross-sectional view taken along the - line in Figure 2, Figure 4 is an explanatory diagram showing the pressure distribution along the - line in Figure 2, and Figure 5 is A, B, C and D are diagrams illustrating pressure fluctuations in each part, and FIG. 6 is a system diagram showing another embodiment of the present invention. 3...Suction pipe, 4...Pump, 7...Discharge pipe,
8...Pressure tank, 10...Automatic air supply device,
11... Supply unit, 12... Fluid diode, 13
... Intake valve, 14 ... Casing, 17 ... Piston, 18 ... Coil spring, 19 ... Lower chamber, 2
1...Upper chamber, 22...Through hole (outlet), 23...
...Recess, 26...Intake pipe, 27...Intake port, 28
... Vortex chamber, 29 ... Inlet, 31 ... Verofram.

Claims (1)

[Claims] 1 A device that automatically replenishes air into a pressure tank that contains water and compressed air and is connected to the discharge side of a pump, which has a partition wall such as a piston or bellofram that can be vertically displaced by upward pressure. The lower chamber partitioned by the partition wall is connected to the supply part casing to the suction side of the pump, and the inlet opening tangentially to the peripheral wall of the volute chamber is communicated with the pressure tank. , a vortex type fluid diode having an outlet opening in the axial direction at the center of the volute chamber and communicating with an upper chamber partitioned by a partition wall of the supply section casing; and one end opening at the center of the vortex chamber. and an intake valve connected to the other end of the intake pipe.