JPH0617752A - Pulsation reducing device - Google Patents

Abstract

PURPOSE:To provide a pulsation reducing device which saves the manpower and performs rapid and accurate regulation by a method wherein when a fluctuation in a liquid pressure exceeds a specified range during suppression of pulsation phenomenon of pump transfer liquid by a reciprocating pump, a gas-sealing pressure is automatically regulatable according to the situation. CONSTITUTION:When a diaphragm 14 is moved from a reference position S in a direction, in which a liquid chamber is expanded, owing to a fluctuation in a reduction pressure in a liquid chamber 15, when a stroke exceeds a set value A, a valve 25 is opened through a valve push rod 28 by means of the diaphragm 14, and automatic regulation is effected such that a gas pressure is further exerted on the interior of an air chamber 16 and a sealing pressure is increased. When the diaphragm 14 is moved from the reference position S in a direction in which the liquid chamber is reduced, when a stroke exceeds a set value B, automatic regulation is effected so that a valve 34 is moved to an opening position by means of a slider 33, a gas pressure in the air chamber 16 is released and a sealing pressure is decreased.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a pulsation reducing device which is disposed in a pump transfer liquid pipe line of a reciprocating pump and reduces undesirable pulsation generated in the pipe line.

[0002]

2. Description of the Related Art A pulsation reducing device of this kind is provided in a pump transfer liquid pipe line and has a liquid chamber for taking in and temporarily storing the pump transfer liquid, which is a so-called liquid reservoir. It is also referred to as a pulse damper or accumulator because it has the function of suppressing the pulsating flow caused by the fluctuation of the flow rate and pressure due to the reciprocating movement of the pump by sending it out of the chamber to the pipe line again.

The liquid chamber is isolated from the air chamber in which the gas is sealed by a reciprocating diaphragm such as a bellows, and the gas filling pressure in the gas chamber and the fluctuations in the flow rate and pressure of the pump transfer liquid flowing into the liquid chamber. The diaphragm moves due to the balance to suppress the pulsating flow. A constant liquid chamber volume is set in order to reduce pulsation more effectively, and gas pressure is sealed in the air chamber so that the diaphragm moves around the corresponding reference position. A diaphragm is used because it is often the case that chemicals for semiconductor processing, etc., in which it is necessary to avoid the pump transfer liquid from contacting with external gas, and other contaminants and air trapping in the transfer liquid are often avoided. And is commonly used in this type of pulsation reducing device.

The flow rate and pressure of the pump transfer liquid fluctuates due to the reciprocating motion of the reciprocating pump, and also fluctuates depending on the condition of the supply site and the flow path resistance of the filter provided in the middle of the pipeline. Need to be adjusted accordingly. As shown schematically in FIG. 1 of this type of conventional pulsation reducer and its piping system, a pump transfer liquid is transferred by a reciprocating pump 1 through a piping line 2 and supplied to a supply site (not shown) through a filter 3. To be done. A pulsation reducing device 4 is arranged in the pipe line 2 and a gas pressure supply source 5 is connected to the device 4.
The gas pressure is supplied from the gas pressure supply pipe line 6.
Then, the pressure of the transfer liquid is sequentially measured by the pressure gauge 7 arranged in the pipe line 2, the gas filling pressure of the pulsation reducing device 4 is obtained based on the measured value, and the pressure reducing valve 8 provided in the pipe line 6 is obtained.
Is adjusted to match the filling pressure, and the adjustment work is performed so that an appropriate gas filling pressure can always be obtained while checking this with a pressure gauge 9 arranged in the pipe line 6.

[0005]

In the above-mentioned conventional pulsation reducing device, it is necessary to perform all the adjusting work of the gas pressure filling pressure manually, for example, the clogging of the filter 3 in the transfer liquid pipe line 2 or the like. When the pressure reducing valve 8 is operated while the pressure gauge 7 monitors the fluctuations in the liquid delivery pressure generated in step 2, and the gas filling pressure is adjusted and followed, a great deal of labor is required for the performed work, and quick and accurate adjustment is difficult. there were.

Therefore, the present invention has been made in view of the above-mentioned problems of the prior art, and an object thereof is to improve the flow rate and pressure of the transfer liquid introduced into the liquid chamber beyond a predetermined range. (EN) A pulsation reducing device capable of automatically adjusting the gas filling pressure, contributing to labor saving of human labor, and enabling quick and accurate adjustment.

[0007]

In order to achieve the above object, the present invention provides a device body in the form of a hermetically sealed container, a liquid chamber provided in the device body for circulating a pumped liquid, and for reducing pulsation. Separating the air chamber in which the gas pressure is sealed and reciprocating a diaphragm in accordance with the balance between the fluctuation of the flow rate and pressure of the pump transfer liquid flowing into the liquid chamber and the gas sealing pressure in the air chamber; Gas pressure introduction for introducing the gas pressure from the gas pressure supply means into the air chamber when increasing the enclosed pressure in the air chamber, on the premise of a configuration including a gas pressure supply means for supplying the gas pressure to the air chamber A passage and a gas pressure lead-out passage for leading out gas pressure from the air chamber to the outside when the enclosed pressure in the air chamber is reduced, and the introduction passage is normally closed in the gas pressure introduction passage. A first valve for A first interlocking member that is provided with a second valve that is closed at the time, and is operable to open the first valve when the diaphragm moves beyond a predetermined stroke in the direction of expanding the liquid chamber. Is provided between the first valve and the diaphragm, and is operable to open the second valve when the diaphragm moves beyond a predetermined stroke in the direction of contracting the liquid chamber. The pulsation reducing device is characterized in that an interlocking member is provided between the second valve and the diaphragm.

[0008]

In the above pulsation reducing device of the present invention,
When the hydraulic pressure of the pumped liquid in the liquid chamber rises due to the progress of the clogging of the filter in the conduit and is excessively pushed in the direction in which the diaphragm expands and exceeds a certain stroke, Since the diaphragm opens the first valve via the first interlocking member, the gas pressure is introduced from the gas pressure supply means into the air chamber through the gas pressure introduction passage to increase the enclosed pressure, and the diaphragm is Further movement beyond the stroke is prevented. On the other hand, when the fluctuation of the hydraulic pressure of the pumped liquid that has flowed in with a pulsating flow decreases beyond the normal range, the gas sealing pressure overcomes and the diaphragm is excessively pushed in the direction of contraction. When the stroke exceeds a certain stroke, the diaphragm opens the second valve through the second interlocking member, so that the gas pressure is discharged from the air chamber to the outside through the gas pressure discharge passage. The encapsulation pressure of the is reduced, preventing further movement of the diaphragm beyond the stroke.

Thus, even if the diaphragm fluctuates according to the pressure difference between the fluctuation pressure of the pump transfer liquid flowing into the liquid chamber with a pulsating flow and the sealed pressure in the air chamber, the fluctuation range of the diaphragm is the same. It is automatically adjusted to be within a certain range in both the expanding direction and the contracting direction, and the volume of the liquid chamber is always maintained at a predetermined size desired to reduce pulsation.

[0010]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS An embodiment of the pulsation reducing device of the present invention will be described below with reference to FIGS.

FIG. 2 shows a pulsation reducing device and a piping system of the present invention by giving the same reference numerals to corresponding parts, in comparison with FIG. 1 showing a conventional example. The pulsation reducing device 4 is
It is arranged in the pump transfer liquid pipe line 2 of the reciprocating pump 1,
The pulsation caused by the reciprocating motion of the reciprocating pump 1 accompanied by fluctuations in the flow rate and pressure of the transfer liquid in the pipe line 2 is caused by the device 4
And is transferred to a supply site (not shown) through the filter 3. Gas pressure is supplied to the pulsation reducing device 4 from a gas pressure supply source 5 as a gas filling pressure through a gas pressure supply pipe line 6. Reference numeral 6a is a gas pressure derivation pipe line for deriving the gas pressure when the gas pressure is adjusted to be lowered.

As can be seen from the above structure, in the structure using the pulsation reducing device 4 of the present invention, the pressure gauges 7 and 9 arranged in both pipe lines 2 and 6 are different from the conventional structure shown in FIG. The pressure reducing valve 8 is not necessary at all, and the gas filling pressure can be automatically adjusted when the fluctuation of the hydraulic pressure of the pump transfer liquid flowing through the pump transfer liquid pipe line 2 exceeds a predetermined range as described in detail in FIG. It is like this.

In the pulsation reducing device 4 of the present invention shown in FIG. 3, reference numeral 10 denotes upper and lower disc-shaped end members 10a in the main body of the device.
10b and a cylindrical tubular portion 10c disposed between both ends 10a, 10b, and these three members are fixed to each other in the axis X-X direction by tightening members such as bolts (not shown) to form a hermetically sealed container. Has been done. The upper end member 10a includes a pump transfer liquid inlet 11 and outlet 12.
Is formed, and the pipe line 2 is connected to each of the ports 11 and 12. Transfer liquid passages 13a and 13b are formed in communication with the inlet 11 and the outlet 12, respectively.
13b communicates with a liquid chamber 15 defined by a diaphragm 14 constituted by a bellows in the present embodiment.
It forms part of 5. In this embodiment, the pump transfer liquid inlet 11 and the pump outlet 12 are individually provided so that the entire amount of the transfer liquid passes through the liquid chamber 15. However, unlike this, a single inlet and outlet It is also possible to provide a single passage to the liquid chamber 15 and cause a part of the transfer liquid to flow into the liquid chamber via this inlet / outlet to increase / decrease the storage amount of the liquid chamber, thereby enhancing the pulsation reducing effect.

The base 14a of the diaphragm 14 is clamped and fixed in a liquid-tight state between the end member 10a of the apparatus main body 10 and the cylindrical portion 10c, and the bellows-shaped expansion / contraction portion 14b has an axis X- of the apparatus main body 10.
It can be expanded and contracted in the X direction, and due to this expansion and contraction, the diaphragm 1
The closed end plate 14c of No. 4 translates in the direction of the axis XX.

By forming the diaphragm 14 and at least the upper end member 10a of the apparatus main body 10 from a highly corrosion-resistant plastic, it is suitable for handling a chemical solution or the like as a pump transfer liquid.

An air chamber 16 which is isolated from the liquid chamber 15 and encloses the adjusted gas pressure is defined in the apparatus main body 10 by the diaphragm 14. The lower end member 10b has a gas pressure inlet 17 to which the gas pressure supply pipe line 6 is connected, a gas pressure outlet 18 to which the gas pressure derivation pipe line 6a is connected, an air chamber 16 and an inlet 1.
Gas pressure introducing passage 19 through which 7 and outlet 18 communicate, respectively
And a gas pressure lead-out path 20 is formed.

The gas pressure introduction passage 19 and the discharge passage 20 are provided with first and second valve mechanisms 21 and 22, respectively, and these valve mechanisms 21 and 22 are always used to introduce these introduction passages 1 and 2.
9, the lead-out path 20 is closed. First valve mechanism 21
Is a valve chamber 24 communicating with the introduction passage 19, a valve 25 formed of a ball valve, a valve spring 26 for urging the valve 25 to a closed position, and an inner end portion of the valve 25 serving as a valve seat and the introduction passage 19 And a guide member 27 screwed and fixed to the lower end member 10b. A valve push rod 28 forming a first interlocking member is slidably movable in the axis XX direction in the shaft hole 27a of the guide member 27, and the gas freely flows around the push rod 28. Insertion is guided with a gap of. This valve push rod 28
Although the lower end of the valve is in contact with the valve 25, the weight of the push rod 28 does not move the valve 25 from the closed position shown in FIG. The upper end of the push rod 28 has a shaft hole 27a.
It is positioned further away from the closed end plate 14c of the diaphragm 14 at the reference position S in the state of the average pressure of the liquid pressure in the liquid chamber 15 by a stroke A.

The second valve mechanism 22 has a lower end screwed into and fixed to the lower end member 10b and has a tubular guide member 31 having a valve chamber 30 formed therein, and is slidably fitted to the guide member 31. A second interlocking member which is urged upward by a valve spring 32 in the valve chamber 30 and whose upper end is always kept in contact with the central portion of the lower surface of the closing end plate 14c of the diaphragm 14 by the urging. Slider 33
And a rod-shaped valve 34 that has an enlarged engagement portion 34a that can be engaged with the lower end bent portion 33a of the slider 33 and that can relatively move in the axis XX direction through the lower end opening of the slider 33. In the illustrated state in which the diaphragm 14 is in the reference position S, the expansion engagement portion 34a is not attached to the slider 33.
It is positioned away from the lower end bent portion 33a by a stroke B. A through hole 35 is formed in a side portion of the guide member 31 to connect the air chamber 16 and the valve chamber 30.
The gas also slightly communicates with the clearance between the fitting portion between the slider 33 and the tubular guide member 31. The valve 34 is normally held in the closed position shown in the figure which blocks the outlet passage 20.

An adjusting operation by the pulsation reducing device 4 configured as described above will be described below. In accordance with the pump operation of the reciprocating pump 1, the transfer liquid in the pipe line 2 enters the liquid chamber 15 through the inlet 11 and the transfer liquid passage 13a as shown by the arrow, and further the transfer liquid passage 13b and the outlet 12 are provided. Is again sent to the pipe line 2 through the filter, and is transferred to a supply site (not shown) via the filter 3. During this period, the pump transfer liquid in the pipeline 2 flows as a pulsating flow accompanied by fluctuations in the flow rate and pressure due to the reciprocating motion of the reciprocating pump, but from the inlet 11 to the liquid chamber 15 of the pulsation reducing device 4. Transfer liquid passage 13a
And enters the liquid chamber 15. When the pressure of the transfer liquid rises, the volume of the liquid chamber 15 resists the filling pressure in the air chamber 16 and the diaphragm 14 expands to increase the storage amount of the transfer liquid.
3b, the pressure rise of the transfer liquid sent out to the pipe line 2 through the delivery port 12 is reduced. Further, when the pressure of the transfer liquid in the liquid chamber 15 drops, the diaphragm 14 is contracted by the sealing pressure in the air chamber 16 and the volume of the liquid chamber 15 is narrowed, and the storage amount of the transfer liquid is reduced. As a result, the pressure drop of the transfer liquid sent out to the pipeline 2 through the transfer liquid passage 13b and the outlet 12 is reduced. In this way, the pressure fluctuation of the transfer liquid is suppressed by passing through the device 4, so that the pulsation phenomenon accompanying this fluctuation is reduced.

The gas filling pressure is set so that the diaphragm 14 is located at the reference position S at the varying average pressure of the liquid pressure against the liquid pressure of the pump transfer liquid, and the preset filling pressure is set in the air chamber 16. Granted. In this case, since the biasing force of the valve spring 32 also opposes the hydraulic pressure, this biasing force is also taken into consideration when setting. The diaphragm 14 has a range in which the diaphragm moves in a direction in which the liquid chamber expands, that is, a stroke A in the downward direction, and a direction in which the liquid chamber contracts, that is, a range in which the diaphragm 14 moves in the upward direction by a stroke B, with respect to the reference position S. Within the range of A + B as a whole, it is set in advance as a moving range in which the effect of suppressing pulsation is sufficiently obtained. In this set state, the hydraulic pressure of the transfer liquid in the pump transfer pipe line 2 rises due to, for example, the progress of clogging of the filter 3, and as a result, the diaphragm 14 strokes in the direction to overcome the gas filling pressure 16 and expand the liquid chamber. When the situation of moving beyond A is reached, the closing end plate 14c of the diaphragm comes into contact with the valve push rod 28 and pushes down the rod 28. As a result, the rod 28 opens the valve 25 against the valve spring 26, and a gas pressure is applied from the gas pressure supply pipe line 6 through the gas pressure introducing passage 19 as shown by an arrow so that the sealed pressure in the air chamber 16 is increased. Is automatically adjusted to raise. Therefore,
The diaphragm 14 is prevented from moving beyond the stroke A. Then, since the diaphragm 14 moves toward the reference position S as the filling pressure rises, the closed end plate 14c separates from the valve push rod 28, the valve 25 returns to the closing position again, and the gas filling pressure is adjusted. Fixed.

Further, when the pressure of the pumped liquid is lowered and the diaphragm 14 is pushed by the gas filling pressure to move beyond the stroke B in the direction of contracting the liquid chamber, the diaphragm 14 is moved. The slider 33 rises due to the bias of the valve spring 32 as the closing end plate 14c of the valve 3 rises, and the lower end bent portion 33a moves to the valve 3
4 is engaged with the enlarged portion 34a. As a result, the valve 34 is pushed up to open the outlet passage 20, so that the gas in the air chamber 16 is discharged to the gas pressure outlet pipe passage 6a via the outlet passage 20 and the outlet 18 so that the filling pressure is automatically lowered. Adjusted. As a result, the diaphragm 14 is prevented from moving beyond the stroke B, and the reference position S is adjusted according to the adjustment of the reduction of the enclosed pressure.
Since it moves toward, the slider 33 also descends and the lower end bent portion 33a moves away from the enlarged portion 34a of the valve 34.
As a result, the valve 34 returns to the closed position again, and the gas filling pressure is fixed in the adjusted state.

As described above, when the fluctuation of the hydraulic pressure of the pump transfer liquid becomes large and the diaphragm 14 exceeds the set range suitable for enhancing the pulsation reducing effect, as described above, the first and second The valve mechanisms 21 and 22 are selectively operated according to the moving direction of the diaphragm, and the gas filling pressure is automatically adjusted.

In the embodiment, the slider 33 is attached to the diaphragm 1.
Although it is configured to contact the closed end plate 14c of No. 4,
A configuration in which these are integrally fixed and the valve spring 32 is omitted is also possible. Further, it is also possible to fix the upper end portion of the valve push rod 28 to the closed end plate 14c of the diaphragm and to provide a gap corresponding to the stroke A between the valve push rod 28 and the valve 25. In addition, the valve mechanism 2
The valves 25 and 34 of 1 and 22 may be configured by other valves such as cocks, and the cocks and the like may be opened and closed when the diaphragm 14 exceeds the set stroke, and the structure is not limited to this embodiment. Furthermore, the diaphragm is not limited to the bellows structure of the embodiment, but the present invention can be applied to a diaphragm structure and is not limited to the embodiment.

[0024]

As described above, according to the pulsation reducing device of the present invention, the pressure fluctuation of the transfer liquid is reduced during the operation of reducing the pulsation accompanying the fluctuation of the flow rate / pressure of the pump transfer liquid by the reciprocating motion of the diaphragm. When the diaphragm becomes larger and exceeds the set range, the first and second valves are selectively operated according to the moving direction of the diaphragm in conjunction with the movement of the diaphragm to quickly and quickly increase the gas filling pressure. Accurate automatic adjustment does not require any human labor for adjustment work, can contribute to labor saving of labor, and does not require a pressure gauge or pressure reducing valve for adjustment, thus simplifying the piping system and reducing costs. Various effects such as down can be achieved.

[Brief description of drawings]

FIG. 1 is a schematic diagram showing a conventional pulsation reducing device and its piping system.

FIG. 2 is a schematic view of a pulsation reducing device according to the present invention and a piping system thereof, which is shown in comparison with FIG.

FIG. 3 is an enlarged vertical sectional view showing the pulsation reducing device of FIG. 2 taken out.

[Explanation of symbols]

 4 Pulsation reducer 10 Device body 14 Diaphragm 15 Liquid chamber 16 Air chamber 21 First valve mechanism 22 Second valve mechanism 28 Valve push rod (first interlocking member) 33 Slider (second interlocking member)

Claims (1)

[Claims] 1. A pulsation reducing device which is disposed in a pump transfer liquid pipe line of a reciprocating pump and reduces a pulsation of a pump transfer liquid, the device main body being in the form of a sealed container, and provided in the device main body. The liquid chamber in which the pumped liquid is circulated and the air chamber in which the gas pressure for reducing pulsation is sealed are separated from each other, and fluctuations in the flow rate and pressure of the pumped liquid flowing into the liquid chamber and the gas filling pressure in the gas chamber Of a diaphragm that can reciprocate depending on the balance of the gas pressure, and a gas pressure supply means for supplying a gas pressure to the air chamber. The apparatus main body is provided with a gas pressure introduction path for introducing gas pressure into the air chamber, and a gas pressure derivation path for deriving gas pressure from the air chamber to the outside when the enclosed pressure in the air chamber is reduced. A first valve that normally closes the introduction passage is provided in the introduction passage. In addition, the gas pressure outlet passage is provided with a second valve that normally closes the outlet passage, and the first valve is opened when the diaphragm moves in a direction of expanding the liquid chamber beyond a predetermined stroke. First operable to open
Is provided between the first valve and the diaphragm, and is operable to open the second valve when the diaphragm moves in a direction of reducing the liquid chamber over a predetermined stroke. A pulsation reducing device comprising a second interlocking member provided between the second valve and the diaphragm.