JPH09203380A - Reciprocating pump with automatic degassing mechanism - Google Patents

Abstract

PROBLEM TO BE SOLVED: To simplify the structure of a degassing valve, carry out realize the miniaturization inexpensively. SOLUTION: A reciprocating pump with an automatic degassing mechanism leads liquid into a pump chamber 5 via suction valves 9 and 10, by the reciprocating movement of a diaphragm 3 facing a pump chamber 5, to discharge the liquid from the pump chamber 5 via discharge valves 15 and 16. A passage 23, direct behind the discharge valves 15 and 16 is branched to a discharge liquid passage 24 horizontally extended to the discharge outlet, and a degassing passage 25 extending directly upward, and a degassing valve 25 is arranged in the passage 25. A check valve mechanism 28, for producing back pressure at the time of discharge, is provided on the discharge liquid passage 24. A degassing valve 32 is constituted of one valve ball and valve heets arranged in the upper and lower parts of the valve ball. The valve ball and the lower side valve sheet prevent the leakage of liquid and gas from outside at the time of a suction stroke, and the valve ball and the upper side valve sheet constitute an incomplete seal, thereby making the liquid and the gas slightly exhausting outside at the time of a discharge stroke.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a reciprocating pump for introducing liquid into a pump chamber through a suction valve by reciprocating a diaphragm, a piston or the like and discharging the liquid from the pump chamber through a discharge valve, The present invention relates to a reciprocating pump with an automatic degassing mechanism that automatically removes air, volatile gas, etc. mixed in liquid.

[0002]

2. Description of the Related Art In an electromagnetic metering pump that utilizes the reciprocating movement of a diaphragm, air and volatile gas mixed in the pump chamber lowers the compression efficiency of the pump. Therefore, various automatic degassing mechanisms have been conventionally proposed. For example, in Japanese Patent Laid-Open No. 60-25657, an automatic gas vent valve, which is a mechanism different from the discharge valve, is provided directly above the pump chamber so that the gas contained in the pump chamber is automatically pumped to the outside. It is disclosed to be released into

However, in this reciprocating pump with an automatic degassing mechanism, since the gas vent valve directly faces the pump chamber, the body of the wetted part becomes unnecessarily large, which is uneconomical and the space of the discharge line is large. There is a problem that the capacity becomes large, the wasted capacity of the pump chamber increases, and the pump efficiency decreases. Further, since the gas vent valve is directly connected to the pump chamber, it is necessary to change the design of the pump head itself, which is not compatible with the conventional type pump.

Therefore, as shown in Japanese Patent Laid-Open No. 61-11473, immediately after the discharge valve connected to the pump head, the pipe is branched into a discharge liquid passage and a gas discharge passage, and a gas is introduced into a passage extending directly above. There is also proposed an automatic degassing device in which a vent valve is arranged and a throttle valve mechanism for generating a back pressure at the time of discharge is provided in a pipe communicating with a discharge liquid passage. In this device, the gas vent valve is composed of two corrugated cardboard valves, the valve ball having a smaller specific gravity than the liquid is arranged in the lower stage, and the valve ball having a larger specific gravity than the liquid is arranged in the upper stage, and the valve ball in the upper stage is arranged. The valve seat and the valve seat prevent the leakage of air from the outside at the time of the intake stroke as in the normal ball check mechanism, and the lower valve ball and the valve seat operate so as to suppress the leakage of the liquid at the discharge stroke. .

[0005]

However, in the above-described conventional automatic degassing device, the degassing valve is composed of the two-stage ball valve, so that the structure of the degassing valve is complicated, and the device is also complicated. Also has the drawback of being large. In addition, since the lower valve ball of this device is light, it adheres to the valve seat immediately above due to the liquid viscosity, which makes it difficult to smoothly remove gas.

The present invention has been made to solve the above problems, and provides a reciprocating pump with an automatic degassing mechanism, which has a simple structure and can be made compact and inexpensive. With the goal. Another object of the present invention is to provide a reciprocating pump with a degassing mechanism, which has excellent compatibility and can be applied to a conventional pumping mechanism only by replacing the degassing unit.

[0007]

A reciprocating pump with a degassing mechanism according to the present invention introduces liquid into a pump chamber through a suction valve by reciprocating motion of a reciprocating member facing the pump chamber, and through a discharge valve. While discharging liquid from the pump chamber, a passage immediately after the discharge valve is branched into a discharge liquid passage that extends horizontally to the liquid discharge port and a gas vent passage that extends immediately above, and a gas vent valve is provided in the gas vent passage. In the arranged reciprocating pump with an automatic degassing mechanism, a check valve mechanism for generating a back pressure at the time of discharge is provided in the discharge liquid passage, and the degassing valve is arranged at one valve ball and above and below it. The valve ball and the lower valve seat prevent the liquid and gas from leaking from the outside during the suction stroke, and the valve ball and the upper valve seat. Characterized in that is a liquid and gas during the discharge stroke constitutes an incomplete seal those to be discharged slightly outside.

Another reciprocating pump with a degassing mechanism according to the present invention comprises a pump head having a pump chamber, a suction valve connected to the lower end of the pump head for introducing liquid to the pump chamber during a suction stroke. A discharge valve connected to the upper end of the pump head for discharging liquid from the pump chamber during a discharge stroke; and a degassing unit detachably mounted immediately above the discharge valve, wherein the degassing unit is A check valve for forming a discharge liquid passage extending horizontally from a passage immediately above the discharge valve to a liquid discharge port and a gas vent passage extending immediately above the discharge valve, for generating a back pressure at the time of discharge in the discharge liquid passage. A mechanism is provided, and a gas vent valve is provided in the gas vent passage. The gas vent valve is composed of one valve ball and valve seats above and below the valve ball. , Characterized in that said valve ball and the upper valve seat and forms an incomplete seal.

The gas venting unit fixes the gas venting valve from above, for example, and forms a gas venting passage between the gas venting valve and the gas venting valve for introducing the liquid and the gas exhausted through the gas venting valve. And a degassing passage communicating with the degassing passage formed by the fixing member and extending in the horizontal direction to the gas discharge port.

Further, the gas venting unit may be one in which the gas venting port is provided directly above the gas venting valve.

According to the first reciprocating pump with the automatic degassing mechanism of the present invention, the degassing valve is constituted by one valve ball and valve seats arranged above and below the valve ball, and the valve ball and the upper valve seat. Since the space between them is incompletely sealed, the valve ball and the lower valve seat prevent the liquid and gas from leaking from the outside during the suction stroke, just like a normal ball check valve, and only slightly during the discharge stroke. The gas mixed in the liquid is efficiently discharged to the outside through the incomplete seal between the valve ball and the upper valve seat. Moreover, since the check valve mechanism is provided in the discharge liquid passage to apply the back pressure to the liquid discharge port side, the degassing can be smoothly performed in a short time.

According to the present invention, since only one valve ball is required, the structure of the degassing valve is much simpler than the conventional one. Moreover, according to the present invention, it is possible to use a valve ball having a larger specific gravity than the liquid, and the adhesion between the upper valve seat and the valve ball is intentionally deteriorated to form an incomplete seal. That is, the valve ball is sucked to the lower valve seat side during the suction stroke, so that the valve ball does not adhere to the upper valve seat, and the degassing operation can be performed without trouble. .

According to the second reciprocating pump with a gas venting mechanism of the present invention, the gas venting unit incorporating the above-mentioned gas venting valve and check valve mechanism is attached to and detached from the upper end of the pump head via the discharge valve. Since it is configured so that it can be installed, the reciprocating pump with the automatic degassing function described above can be constructed at low cost simply by mounting the degassing unit on the discharge side of the conventional reciprocating pump that does not have a degassing mechanism. can do.

[0014]

Preferred embodiments of the present invention will be described below with reference to the accompanying drawings. FIG. 1 is a sectional view showing a main part of an electromagnetic metering pump with an automatic degassing mechanism according to an embodiment of the present invention. At the tip of the drive shaft 1 that is reciprocally driven by the electromagnetic force of the pump body (not shown),
A flexible diaphragm 3 is attached via an insert bolt 2. The diaphragm 3 forms a pump chamber 5 between the diaphragm 3 and the pump head 4 at the center of the front surface, and the peripheral portion of the diaphragm 3 is held by the bracket 6 and the pump head 4. The pump head 4 is formed with an intake liquid passage 7 extending obliquely downward from the pump chamber 5 and a discharge liquid passage 8 extending obliquely upward from the pump chamber 5.

At the lower end of the pump head 4, a suction liquid passage 7 is provided.
The two-stage intake valves 9 and 10 communicating with are connected by an intake valve fixing screw 12 via an O-ring 11. A lower end of the suction valve fixing screw 12 is a suction liquid connection port 13, and a suction nut hose (not shown) is connected to the connection port 13 by a connection nut 14 so that a liquid to be handled from a tank (not shown) is introduced into the pump chamber 5. It is supposed to be introduced. On the other hand, two stages of discharge valves 15 and 16 communicating with the discharge liquid passage 8 are connected to the upper end of the pump head 4 via a O-ring 17 by a discharge valve fixing screw 18. A lock nut 19 is attached to the upper end of the discharge valve fixing screw 18, and a degassing unit 20 is detachably attached directly above the discharge valve 16 by the lock nut 19.

The degassing unit 20 is constructed as follows. That is, the upper end of the discharge valve fixing screw 18 is liquid-tightly connected to the lower end surface of the substantially cruciform degassing body 21 via the O-ring 22, and is joined by the lock nut 19. Inside the degassing body 21, the discharge valve 1
A passage 23 extending directly above 6 is formed. The passage 23 is branched into a discharge liquid passage 24 extending horizontally from the substantially central portion of the gas vent main body 21 in the right-hand direction in the drawing, and a gas vent passage 25 extending immediately above.

A connection member 29 containing a check valve mechanism 28 is connected to a connection port 26 extending to the discharge liquid passage 24 side of the gas vent main body 21 via a tubular joint 27.
In this example, the check valve mechanism 28 includes a valve ball 28.
a, a valve seat 28b on which the valve ball 28a is seated, a valve guide 28c for guiding the valve ball 28a, and the valve ball 28a for the valve seat 28b.
Spring 28d for pressing to the side to secure a predetermined back pressure
It is composed of A connection nut 31 is screwed into the connection port 30 at the tip of the connection member 29, and a discharge hose (not shown) can be connected via the connection nut 31.

On the other hand, the gas vent passage 2 of the gas vent body 21
Above the 5, the gas vent valve 32 is attached with the gas vent valve fixing screw 3
It is fixed by 3. A degassing passage 34 is formed between the degassing valve 32 and the degassing fixing screw 33, and this passage 34 serves as the discharge liquid passage 2 of the degassing main body 21.
4 communicates with a gas vent passage 35 that extends horizontally on the opposite side. The gas vent passage 35 is sealed from the outside by an O-ring 38 (see FIG. 2) between the gas vent main body 21 and the gas vent fixing screw 33. A connection nut 37 is screwed into the connection port 26 on the discharge side of the gas vent passage 35, and a recovery hose (not shown) for recovering the gas vent and the leak liquid in the tank is connected to the connection nut 37. ing.

FIG. 2 is an enlarged view showing a portion of the gas vent valve 32 in FIG. The gas vent valve 32 is composed of one valve ball 41 and valve seats 42 and 43 arranged above and below the valve ball 41. As shown in a perspective view with a part cut away in FIG. 3, the two valve seats 42 and 43 form a cylindrical space for accommodating the valve ball 41 so that the valve ball 41 can be slightly moved vertically. The lower end of the cylindrical space communicates with the gas vent passage 25, and the upper end communicates with the gas vent passage 34. The valve ball 41 can be made of ceramics or metal, which has a larger specific gravity than the handled liquid. The valve seat 42 has titanium or PVC.
Etc. can be used. Further, rubber can be used for the valve seat 43. Between the lower surfaces of the valve seats 42 and 43 and the gas vent main body 21, the valve seat 4 of the gas vent main body 21 is provided.
An annular spacer 45 for preventing the bite from penetrating into 3 is arranged.

FIG. 3 (b) is a view taken along the line AA of FIG. 2 with the gas vent valve 32 removed. That is, the cross-shaped groove 4 is provided at the upper end of the internal space of the gas release valve fixing screw 33.
4a are formed, and four arcuate vertical grooves 44b are formed on the inner wall side surface so as to follow these grooves 44a. These vertical grooves 44b are further provided at the tip of the gas release valve fixing screw 33.
Following the one groove 44 c, it further communicates with the gas vent passage 35 through the outer peripheral portion of the valve seat 42. Therefore, the gas and the liquid leakage are discharged from the connection port 36 through the path shown by the dotted line in FIGS. 2 and 3B.

The valve ball 41 and the lower valve seat 4
A complete seal similar to that of a normal check valve is formed between the two. On the other hand, the portion of the upper valve seat 42 that contacts the valve ball 41 is processed by a method such as an eccentric press described later, and the valve ball 41 and the upper valve seat 4 are
It is constructed so that an incomplete seal is formed between the two.
FIG. 4 is a diagram for explaining an eccentric press for forming such an incomplete seal. That is, in a normal check valve, as shown in FIG. 3A, in order to improve the sealing performance, the valve ball 41 is seated on the valve seat 42, and the valve ball 41 is mounted straight on the pedestal 51 and copied by the press 52. It is pressed, but the gas vent valve 32 of the present invention
Then, as shown in FIG. 3B, the pedestal 51 is tilted by θ and pressed. As a result, the press mark 54 is eccentric to the hole 53 of the valve seat 42 as shown in FIG.

Next, the operation of the electromagnetic metering pump with the automatic degassing mechanism thus constructed will be described. In the suction stroke in which the diaphragm 3 retracts together with the drive shaft 1, the suction valves 9 and 10 open and the discharge valves 15 and 16 close.
The liquid is sucked into the pump chamber 5 through the suction passage 0 and the suction liquid passage 7. At this time, the gas discharge valve 32 has the valve ball 41.
Is in close contact with the lower valve seat 43, so the passage 2
No extra gas or liquid flows into the inside of 3, 24 or 25 from the outside.

Next, in the discharge stroke in which the diaphragm 3 advances together with the drive shaft 1, the suction valves 9 and 10 are closed and the discharge valves 15 and 16 are opened, so that the liquid in the pump chamber 5 passes through the discharge valves 15 and 16. Is discharged to the passage 23 side. At this time, the hydraulic pressure in the passages 23, 24, 25 is changed to the check valve mechanism 2
When the back pressure applied by 8 is overcome, the check valve mechanism 28 opens and the discharge liquid is discharged from the discharge side connection port 30 to the discharge side hose (not shown). Pole valve 41
Although a small amount of liquid leaks from the incomplete seal between the upper valve seat 42 and the upper valve seat 42 to the gas vent passage 34 side, the leaked liquid is recovered to the tank side via a recovery hose (not shown). If gas is mixed in the discharge liquid, the passage 2
Since the liquid pressure of 3, 24, 25 does not rise sufficiently, the check valve mechanism 28 remains closed, and the gas rising in the liquid is discharged between the valve ball 41 of the gas vent valve 32 and the upper valve seat 42. Is quickly discharged together with a slight amount of liquid to the gas vent passage 35 side through the incomplete seal. After degassing, the liquid pressure in the passages 23, 24, 25 increases, the check valve mechanism 28 opens, and the liquid is discharged.

On the other hand, when the discharge side pipe pressure (not shown) increases, the check valve mechanism 28 is closed.
This prevents the liquid pressure in the passages 23, 24, 25 from increasing more than necessary and causing unnecessary liquid leakage from the gas vent valve 32. Further, the check valve mechanism 28 includes the passages 23, 24, 2
It is prevented that the hydraulic pressure in 5 increases and the valve ball 41 remains pressed against the valve seat 42, and the check function of the valve does not function and the air bleeding function deteriorates.

As described above, according to the pump of the above embodiment, the structure of the gas vent valve 32 is simplified and the number of parts can be reduced. Since the degassing unit 20 is only attached to the pump having the conventional structure, it has an advantage of high compatibility with the conventional pump. Further, in the pump of this embodiment, the gas vent valve fixing screw 33 for fixing the gas vent valve 32 and the connection port 36 which is a gas discharge port are separate members, so that a hose or the like is connected to the connection port 36. There is also an advantage that the gas vent main body 21 can be prevented from accidentally biting into the valve seat 43 when connecting. In addition, in this embodiment, the discharge liquid passage 24 and the degassing passage 35 are formed in a direction different from each other by 180 ° in the horizontal direction, but both are formed in the horizontal direction, for example, at 90 ° or another angle. Good.

FIG. 5 is a sectional view showing a main part of a pump according to another embodiment of the present invention. In the previous embodiment, the gas venting direction of the gas venting unit 20 was horizontal.
In this embodiment, the gas venting unit 60 is vented in the vertical direction. That is, the gas release valve fixing screw 6
1 is a gas vent valve 3 at its lower end through an O-ring 62.
2 is connected to the degassing body 63 in a liquid-tight manner. An upper end portion of the gas vent valve fixing screw 61 serves as a gas vent hose connection port 64, and a connection nut 65 is screwed therein. In this embodiment, since the gas vent passage 66 is formed upward, there is an advantage that the gas can escape more easily than the previous embodiments.

6 and 7 are views showing another example of the structure of the check valve mechanism. FIG. 6 shows an example of a rubber tube type check valve mechanism 70. Degassing body 21
The liquid that has passed through the discharge liquid passage 24 is introduced into the hole 73 inside the central protrusion 72 on the tip side of the joint 71 connected to the connection port 26, and connects the outer peripheral groove 74 of the central protrusion 72 and the hole 73. It is discharged to the outer peripheral groove 72 side through the hole 75. Since the rubber tube 76 is attached to the central protrusion 72,
When the liquid pressure overcomes the contact pressure between the rubber tube 76 and the central protrusion 72, the liquid is discharged from between the inner surface of the rubber tube 76 and the central protrusion 72 to the connection port 30 side via the connecting member 77.

FIG. 7 shows an example of a check valve mechanism 80 using a so-called umbrella valve. An umbrella-shaped sheet member 82 made of, for example, plastic is attached to the joint 81 connected to the connection port 26 on the liquid discharge side of the degassing main body 21 via a gasket 83. Sheet member 8
2, the front end side has a large diameter and the rear end side has a small diameter, and slits 84 extending in the vertical direction are formed at, for example, three locations in the circumferential direction of a cylindrical portion connecting the front end and the rear end. A rubber valve 85 is mounted between the front end and the rear end of the seat member 82 with a slight tension applied. The discharge liquid discharged from the connection port 26 of the discharge liquid passage 24 is discharged to the connection member 86 side by pushing the valve 85 upward through the slit 84 of the sheet member 82.

Depending on the type of liquid to be handled, it may not be possible to use a metal member from the viewpoint of corrosion resistance, but these check valve mechanisms 70, 80 do not use the metal spring 28d as in the previous embodiments. , Can be applied to these applications.

[0030]

As described above, according to the present invention, only one valve ball is required, the structure of the gas vent valve is much simpler than that of the conventional one, and the gas venting operation is surely performed. It has the effect of being performed.

[Brief description of drawings]

FIG. 1 is a sectional view of a main part of an electromagnetic metering pump with an automatic degassing mechanism according to an embodiment of the present invention.

FIG. 2 is an enlarged view showing a gas vent valve portion of the pump.

FIG. 3 is a partially cutaway perspective view of the gas vent valve and a view taken along the line AA in FIG. 2 with the gas vent valve removed.

FIG. 4 is a view for explaining the manufacturing method of the gas vent valve.

FIG. 5 is a sectional view of an essential part of an electromagnetic metering pump with an automatic degassing mechanism according to another embodiment of the present invention.

FIG. 6 is a cross-sectional view showing the periphery of a check valve mechanism of still another embodiment of the present invention.

FIG. 7 is a cross-sectional view showing the periphery of a check valve mechanism of still another embodiment of the present invention.

[Explanation of symbols]

1 ... Drive shaft, 3 ... Diaphragm, 4 ... Pump head, 5
... pump chamber, 7 ... suction liquid passage, 8, 24 ... discharge liquid passage,
9, 10 ... Suction valve, 15, 16 ... Discharge valve, 20, 60 ...
Degassing unit 21, 63 ... Degassing body, 25,
34, 35, 66 ... Gas vent passages, 28, 70, 80 ...
Check valve mechanism, 32 ... Gas vent valve, 41 ... Valve ball, 42, 43 ... Valve seat.

Claims (4)

[Claims] 1. A liquid is introduced into the pump chamber through a suction valve by the reciprocating motion of a reciprocating member facing the pump chamber, the liquid is discharged from the pump chamber through a discharge valve, and a passage immediately after the discharge valve is provided. In a reciprocating pump with an automatic degassing mechanism, which branches into a discharge liquid passage that extends horizontally to the liquid discharge port and a gas vent passage that extends immediately above, and a gas vent valve is disposed in the gas vent passage. A check valve mechanism for generating a back pressure at the time of discharge is provided, and the gas vent valve is composed of one valve ball and valve seats arranged above and below the valve ball, and the valve ball and the lower valve seat. Means that the liquid and gas are prevented from leaking from the outside during the suction stroke, and the valve ball and the upper valve seat constitute an incomplete seal to prevent the liquid and gas from leaking during the discharge stroke. Automatic venting mechanism with the reciprocating pump, characterized in that is obtained by allowing the discharge to the outside. 2. A pump head having a pump chamber, a suction valve connected to a lower end of the pump head to introduce liquid to the pump chamber during a suction stroke, and a suction valve connected to an upper end of the pump head during a discharge stroke. A discharge valve for discharging the liquid from the pump chamber and a degassing unit detachably mounted directly above the discharge valve are provided, and the degassing unit is arranged horizontally from a passage immediately above the discharge valve to a liquid discharge port. An extended discharge liquid passage and a gas vent passage extending directly above the discharge valve are formed, and a check valve mechanism for generating a back pressure at the time of discharge is provided in the discharge liquid passage, and the gas vent passage is provided with the check valve mechanism. A degassing valve is provided, and the degassing valve includes one valve ball and valve seats above and below the valve ball, and the valve ball and the upper valve seat. Automatic venting mechanism with the reciprocating pump, characterized in that to form an incomplete seal. 3. The gas venting unit fixes the gas venting valve from above and forms a gas venting passage between the gas venting valve and the gas venting valve for introducing liquid and gas exhausted through the gas venting valve. 3. The automatic degassing device according to claim 2, further comprising: a fixing member that is provided with the fixing member; Reciprocating pump with mechanism. 4. The reciprocating pump with an automatic degassing mechanism according to claim 2, wherein the degassing unit is provided with a gas discharge port directly above the degassing valve.