JPH08159016A - Pulsation width suppress device for pump - Google Patents

Abstract

PURPOSE: To reduce a pulsation width regardless of fluctuation of discharging pressure in a pump as well as suppressing pulsation by discharging pressure of transfer liquid, and improve maintaining performance such as assembly and repairing by simplifying a constitution. CONSTITUTION: One intake/exhaust switching valve mechanism 7 in which intake/exhaust action is carried out for an air chamber, is provided on the outside of a device main body 1 which is formed in such a way that a liquid chamber 3 for reserving transfer liquid Q temporary and the air chamber 4 are isolated through an diaphragm 5 which is expandable, contractible, and deformable. When discharging pressure in a pump is fluctuated, the capacity of the liquid chamber 3 is controlled by switching operation of the intake/exhaust switching valve mechanism 7 so as to suppress that the capacity exceeds a prescribed range and increase/decrease in the capacity.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a flow rate / pressure resulting from the reciprocating motion of a pump, which is interposed in the middle of a transfer liquid pipe for feeding a transfer liquid such as a semiconductor processing chemical liquid to each part by a reciprocating pump. The present invention relates to a pulsation width suppressing device for a pump that suppresses a pulsating flow that occurs with fluctuations in

[0002]

2. Description of the Related Art As a pulsation width suppressing device of this type,
A structure as disclosed in Japanese Patent Laid-Open No. 6-17752 is known. As shown in FIG. 3, the pulsation width suppressing device disclosed in the publication has a closed container-shaped device body 101 and a transfer liquid Q provided by a reciprocating pump (not shown) provided in the device body 101. And a liquid chamber 102 for temporarily taking in the liquid to perform a liquid collecting action and flowing out, and a gas a which is provided in the apparatus main body 101 and is isolated from the liquid chamber 102 via a stretchable and deformable diaphragm 103.
Is provided, and the diaphragm 103 is expanded and contracted by the pulsation due to the discharge pressure, and the pulsation width is suppressed by the change in the capacity of the liquid chamber 102.

When the discharge pressure of the reciprocating pump fluctuates, it is necessary to limit the expansion and contraction deformation amount of the diaphragm 103 within a predetermined range in order to balance the liquid pressure and the gas pressure. Therefore, in the device shown in FIG. 3, the device main body 101 is provided with the first valve mechanism 105 for air supply and the second valve mechanism 106 for exhaust air, and the diaphragm is changed by the pressure reduction fluctuation in the liquid chamber 102. When 103 is stretched and deformed in the direction of increasing the liquid chamber volume from the reference value S and exceeds the predetermined range A, the diaphragm 103 causes the push rod 10 of the first valve mechanism 105 to move.
The valve 108 is opened via 7 to adjust the gas filling pressure of the air chamber 104 to be high, and the diaphragm 103 is set to the reference value S.
In the case of stretching deformation in the direction of further reducing the volume of the liquid chamber, when the predetermined range B is exceeded, the slider 1 connected to the closed end 103a of the diaphragm 103 causes the valve 1 of the second valve mechanism 106
A configuration has been adopted in which 10 is opened and the gas in the air chamber 104 is discharged to adjust the filling pressure.

[0004]

However, in the conventional pulsation width suppressing device for a pump as described above, the supply and exhaust of air to and from the air chamber 104 are controlled by the first and second valve mechanisms 105, 105.
Since the structure is performed by 106, the structure inside the apparatus main body 101 becomes complicated, and the assembling property becomes extremely poor, and there are many places where failures are expected to occur. if,
When the valve mechanism 105, 106 fails, the device body 10
Although it is necessary to disassemble 1 for repair, etc., a great deal of labor is required for the work for that. Further, when handling a strongly acidic or strongly alkaline transfer liquid Q, the decomposition / repair itself is dangerous.

The present invention has been made in view of the above situation, and simplifies the structure for supplying / exhausting air to / from the air chamber to improve the assemblability, and the number of failure occurrence prediction points is extremely reduced. In addition, it is an object of the present invention to provide a pulsation width suppressing device for a pump, which enables easy and safe disassembly / repair work.

[0006]

In order to achieve the above object, a pump pulsation width suppressing device according to the present invention is a liquid chamber capable of temporarily storing a transfer liquid by a reciprocating pump in a sealed container-like device body. And an air chamber that is isolated from the liquid chamber via a stretchable / deformable diaphragm and in which a gas for pulsation suppression is enclosed, and absorbs pulsation due to the discharge pressure of the transfer liquid due to a change in the volume of the liquid chamber. A pulsation width suppressing device for a pump configured to operate, the operating rod being inserted into the air chamber and capable of responding to the displacement of the diaphragm on the closed end side, and the operating rod being operated by the operating rod. A supply / exhaust switching valve mechanism having a valve body that selectively communicates the supply / exhaust passage communicating with the air supply port and the exhaust port is mounted on the outside of the device body, and the capacity of the liquid chamber is within a predetermined range. When it increases beyond, let the air supply port communicate with the air supply / exhaust passage, One, when the capacity of the liquid chamber is reduced beyond a predetermined range is intended to exhaust ports and configured to communicate with the supply and exhaust passages.

In the pulsation width suppressing device for a pump having the above structure, the supply / exhaust switching valve mechanism has a cylindrical casing having an air supply / exhaust passage communicating with an air supply port, an exhaust port, and an air chamber, and is coaxial with the operating rod. It is preferable to use a slide valve body that is slidably displaceably fitted in a cylinder housed in the cylindrical casing and connected to the above.

[0008]

According to the present invention, when the reciprocating pump causes the transfer liquid to flow out through the liquid chamber in the main body of the apparatus, the liquid chamber capacity increases at the pulsation peak of the discharge pressure of the transfer liquid, and the diaphragm is separated. Expands and deforms to absorb the pressure, and the liquid chamber volume decreases at the valley of the pulsation, and the diaphragm contracts and deforms to increase the pressure of the transfer liquid and absorb the pulsation. In such an operation, when the increase in the liquid chamber capacity exceeds a predetermined range due to the fluctuation of the discharge pressure of the pump, the air supply / exhaust valve mechanism supplies air into the air chamber to increase the enclosed pressure and expand the diaphragm. Deformation is constrained. Also, when the decrease of the liquid chamber capacity exceeds a predetermined range,
The air supply / exhaust valve mechanism evacuates the air chamber to lower the enclosed pressure and restrict the contraction and deformation of the diaphragm. As a result, the expansion and contraction deformation of the diaphragm is restricted within a certain range regardless of the fluctuation of the discharge pressure of the pump, and the pulsation width can be suppressed to be small.

In the pulsation width suppressing device which operates as described above, since the supply and exhaust of the air chamber is performed by the single supply and exhaust switching valve mechanism, the structure is simplified and the assembling property is improved. Moreover, the number of places where failures are expected to occur is reduced. Furthermore, since this supply / exhaust switching valve mechanism is equipped outside the main body of the device, even if a failure occurs, it is not necessary to disassemble the main body of the device and only the supply / exhaust switching valve mechanism is removed for repair. It is possible to easily and safely replace the fluid, regardless of the properties of the transfer liquid.

[0010]

Embodiments of the present invention will be described below with reference to the drawings. FIG. 1 is an overall vertical sectional front view of a pump pulsation width suppressing device according to an embodiment of the present invention. In FIG. 1, reference numeral 1 denotes a closed container-shaped device main body, and a pump is provided at a lower side of the device main body 1. A liquid chamber 3 is formed in which the transfer liquid Q is taken in from the inflow port 2a, temporarily stored, and discharged from the outflow port 2b.

Reference numeral 4 denotes an air chamber formed on the upper side in the apparatus main body 1. The air chamber 4 is separated from the liquid chamber 3 by a diaphragm which can be expanded and contracted, for example, a bellows 5.
The central portion 5a constitutes a part of the liquid chamber 3. The closed end 5b of the bellows 5 is pressed by the elastic force of the spring 18 by the elastic force of the spring 18, which is located in the central portion of the bellows 5 and is oriented in the direction of increasing the capacity of the liquid chamber 3, that is, in the extending direction of the bellows 5. There is.

Reference numeral 7 is an upper wall 1a of the apparatus body 1 on the side of the air chamber 4.
Is a supply / exhaust switching valve mechanism mounted on the outer surface of the supply / exhaust valve. The supply / exhaust switching valve mechanism 7 is configured as shown in FIG. In FIG. 2, reference numeral 8 denotes a bottomed tubular casing, and a slide valve body 10 is fitted in a cylinder portion 9 housed in the casing 8 so as to be slidably displaced along the axial direction (vertical direction) thereof. Has been done. Reference numeral 11 denotes an operating rod which is inserted into the air chamber 4 through a hole 1b formed in the upper wall 1a of the apparatus body 1, and the upper end portion of which is the slide valve body 10
Is connected to the lower end of the shaft coaxially, and the operating rod 1
The connecting flange portion 11a on the lower end side of 1 is connected to the reference position in the tubular connecting member 6.

An air supply port 12 is formed on the lower side of the peripheral wall of the casing 8 and an exhaust port 13 is formed on the upper side thereof. The air supply port 12 has the transfer liquid Q.
The air having a pressure equal to or higher than the maximum pressure value is supplied, and the exhaust port 13 is open to the atmosphere. Ports 14 and 15 are formed on the peripheral wall of the cylinder portion 9 so as to correspond to the air supply port 12 and the exhaust port 13. 1
Reference numeral 6a denotes an air supply / exhaust passage formed in the peripheral wall of the casing 8 for communicating the air chamber 4 with the inside of the cylinder portion 9. 16b is the air chamber 4 through the air supply / exhaust passage 16a.
It is a passage that connects the region surrounded by the collar portion 10a, the cylinder portion 9, and the casing 8. The passage 16b can cancel the influence of the air pressure in the air chamber 4 acting on the slide valve body 10, and the pressure of the transfer liquid Q can be accurately transmitted to the slide valve body 10.

The sliding valve body 10 has three sliding flange portions 10a, 10b, at predetermined intervals in the axial direction thereof.
10c is formed, the space between the central collar portion 10b and the lower collar portion 10c is configured as an air supply space S1, and the space between the central collar portion 10b and the upper collar portion 10a is configured as an exhaust space S2. There is. When the capacity increase of the liquid chamber 3 exceeds the predetermined range A due to the fluctuation of the pump discharge pressure, the slide valve body 10 is displaced upward so that the supply / exhaust passage 16a communicates with the space S1 and the capacity of the liquid chamber 3 is increased. When the decrease exceeds the predetermined range B, the exhaust passage 16a is configured to communicate with the space S2. Reference numeral 17 denotes a spring member that is installed in the casing 8 and that biases the slide valve body 10 with an upward spring force to hold the slide valve body 10 at the reference position.

Next, the operation of the pulsation width suppressing device for a pump having the above structure will be described. When the transfer liquid Q is fed toward a predetermined portion by the operation of the reciprocating pump, the pump discharge pressure causes pulsation due to repetition of the peak portion and the valley portion.

The transfer liquid Q is taken in through the inflow port 2a, temporarily stored in the liquid chamber 3, and then flows out through the outflow port 2a. At this time, when the discharge pressure of the transfer liquid Q is at the peak of the discharge pressure curve, the transfer liquid Q expands and deforms the bellows 5 so as to increase the capacity of the liquid chamber 3, so that the pressure is absorbed. At this time, the flow rate of the transfer liquid Q flowing out from the liquid chamber 3 becomes smaller than the flow rate sent from the pump.

When the discharge pressure of the transfer liquid Q reaches the valley of the discharge pressure curve, the pressure of the transfer liquid Q becomes lower than the enclosed pressure in the compressed air chamber 4 due to the expansion deformation of the bellows 5. Therefore, the bellows 5 contracts and deforms. At this time, the flow rate flowing out of the liquid chamber 3 is larger than the flow rate of the transfer liquid Q flowing into the liquid chamber 3 from the pump. The pulsation is absorbed and suppressed by this repeated operation, that is, the change in the capacity of the liquid chamber 3.

By the way, during the above operation,
When the discharge pressure of the pump fluctuates upward, the capacity of the liquid chamber 3 is increased by the transfer liquid Q, and the bellows 5 is greatly expanded and deformed. The amount of extensional deformation of the bellows 5 is within a predetermined range A
When the temperature exceeds, the slide valve body 10 is slid and displaced upward through the operating rod 11, and the air supply / exhaust passage 16a is communicated with the air supply port 12 through the space S1. Therefore, a high air pressure is supplied from the air supply port 12 to the air chamber 4 through the space S1 and the passage 16a, and the enclosed pressure of the air chamber 4 is increased, whereby the extension deformation amount of the bellows 5 is increased. It is possible to prevent the capacity of the liquid chamber 3 from being restricted and excessively increasing.

On the other hand, when the discharge pressure of the pump fluctuates downward,
The transfer liquid Q reduces the capacity of the liquid chamber 3, and the bellows 5 is greatly contracted and deformed. When the amount of contraction and deformation of the bellows 5 exceeds the predetermined range B, the slide valve body 10 is slidably displaced downward via the operating rod 11, and the supply / exhaust passage 16 is provided.
a communicates with the exhaust port 13 through the space S2. Therefore, the enclosed air a in the air chamber 4 is discharged to the atmosphere from the exhaust port 13 through the air supply / exhaust passage 16a and the space S2, and the enclosed pressure of the air chamber 4 is lowered.
It is possible to prevent the volume of the liquid chamber 3 from being excessively reduced by restricting the amount of shrinkage and deformation of the bellows 5. As a result, the pulsation can be efficiently absorbed and the pulsation width can be suppressed to be small regardless of the fluctuation of the discharge pressure of the pump.

In the above-described operation, since the supply / exhaust of the air chamber 4 is performed by the single supply / exhaust switching valve mechanism 7, the internal structure of the apparatus main body 1 is particularly simplified and the assembly is performed. It is possible to improve reliability and reduce the number of expected failure occurrence points. Further, since the supply / exhaust switching valve mechanism 7 is provided outside the apparatus main body 1, even if the supply / exhaust switching valve mechanism 7 fails, the apparatus main body 1 does not need to be disassembled, and the supply / exhaust switching valve mechanism 7 can be supplied. It is possible to easily repair or replace only the exhaust switching valve mechanism 7. In particular, even if the transfer liquid Q is a chemical liquid such as strongly acidic or strongly alkaline, without touching them,
It is possible to safely repair the supply / exhaust switching valve mechanism 7.

As the supply / exhaust switching valve mechanism 7,
When the tubular valve mechanism using the slide valve body 10 is used as in the above-described embodiment, there is an advantage that the size can be reduced and the communication structure with the air chamber 4 can be simplified. However, other than this, a rotary valve body or the like may be used.

[0022]

As described above, according to the present invention, the pulsation due to the discharge pressure of the pumped liquid can be absorbed by the change in the volume of the liquid chamber, and the liquid when the discharge pressure fluctuates occurs. A supply / exhaust function for the air chamber that is installed outside the main unit to maintain the increase / decrease in the chamber volume within a predetermined range by keeping the pressure balance between liquid pressure and gas pressure to keep the pulsation width small. Since the switching valve mechanism is used, the structure can be remarkably simplified and the assemblability can be improved as compared with the conventional case where two valve mechanisms dedicated to supply and exhaust are incorporated into the main body of the apparatus.
In addition, it is possible to reduce the number of expected failure occurrence points. Moreover, even if this supply / exhaust switching valve mechanism fails, only one supply / exhaust switching valve mechanism needs to be removed without disassembling the main body of the apparatus, so that repair or replacement can be performed very easily. In particular, the present invention has an effect that it is possible to safely perform maintenance such as repair and maintenance even when a transfer liquid having a property that is not preferable for the human body is targeted.

[Brief description of drawings]

FIG. 1 is an overall vertical front view of a pump pulsation width suppressing device according to the present invention.

FIG. 2 is an enlarged vertical cross-sectional front view of a main part of the embodiment.

FIG. 3 is an overall vertical sectional front view of a conventional pulsation width suppressing device.

[Explanation of symbols]

 1 Device Main Body 3 Liquid Chamber 4 Air Chamber 5 Diaphragm 6 Connecting Member 7 Supply / Exhaust Switching Valve Mechanism 10 Slide Valve Body 11 Operating Rod 12 Air Supply Port 13 Exhaust Port 16a Supply / Exhaust Passage Q Transfer Liquid

Front Page Continuation (72) Inventor Ryo Imanishi 1 at 541, Shimuchi Shinjyaku-bata, Sanda City, Hyogo Prefecture Inside the Mita Factory of Nippon Pillar Industry Co., Ltd.

Claims (2)

[Claims] 1. A pulsation suppressing gas is isolated from a liquid chamber capable of temporarily storing a transfer liquid by a reciprocating pump in a sealed container-like apparatus main body, and a diametrically deformable diaphragm with respect to the liquid chamber. A pulsation width suppressing device for a pump that is provided with an enclosed air chamber and is configured to absorb the pulsation due to the discharge pressure of the transfer liquid due to a change in the volume of the liquid chamber, the device being inserted into the air chamber. An operating rod that is responsive to the displacement of the diaphragm on the closed end side, and a valve body that is operated by the operating rod to selectively connect the air supply / exhaust passage communicating with the air chamber to the air supply port and the exhaust port. The supply / exhaust switching valve mechanism is attached to the outside of the apparatus main body, and when the capacity of the liquid chamber increases beyond a predetermined range, the supply port communicates with the supply / exhaust passage, and When the capacity decreases below the specified range, the exhaust port communicates with the supply / exhaust passage. A pulsation width suppressing device for a pump, characterized in that 2. The supply / exhaust gas switching valve mechanism is connected to a cylindrical casing having an air supply / exhaust passage communicating with an air supply port, an exhaust port, and an air chamber, and is coaxially connected to the operating rod so that the cylindrical casing is provided. The pulsation width suppressing device for a pump according to claim 1, wherein the pulsating width suppressing device comprises a slide valve body that is slidably fitted in a cylinder housed in.