JP3051659B2 - Water pump priming device - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a priming device for a water supply pump for priming a water supply pump by driving a rotary vane pump using a self-lubricating vane.

[0002]

2. Description of the Related Art When using a water supply pump such as a centrifugal pump or a turbine pump used for a water pump or a fire pump, it is necessary to first use a priming device to perform so-called "priming".

[0003] The priming using a priming device is performed by evacuating the inside of a water supply pump by a suction action of a rotary vane pump and sucking up water. Therefore, water flows into the rotary vane pump, and there is a possibility that the vane of the rotary vane pump is destroyed by the compression of water due to the rotation of the rotary vane pump, a liquid hammer phenomenon, or the like.

[0004] This phenomenon will be described using a rotary vane pump 1 shown in FIGS. The rotary vane pump 1 has a structure in which a rotor 3 is eccentrically and rotatably provided in a pump case 2, and a vane 5 is slidably incorporated in each groove 4 radially provided in the rotor 3. . The rotary vane pump 1 has a suction side connected to a pipe 6 connected to the inside of a water supply pump, and a discharge side connected to a discharge pipe 7.

[0005] Such a rotary vane pump 1 comprises:
When the rotary vane pump 1 is driven by an engine (not shown), the inside of a water supply pump (not shown) is evacuated by a suction effect due to a volume change of a space surrounded by the vanes 5, the rotor 3 and the pump case 2 accompanying the rotation of the rotor 3, and Water will be drawn into the pump.

[0006] In such a rotary vane pump 1, water flows into the rotary vane pump 1 due to the resistance of a diaphragm type water stop valve, a check valve, a strainer and the like connected to a discharge passage from the water supply pump to the rotary vane pump 1. %, Vane 5 in FIG.
The expansion chamber 8 formed by the rotor 3 and the pump case 2 has a vacuum space. Therefore, as shown in FIG. 10B, at the moment when the rotor 3 rotates and the discharge port 9 communicates with the expansion chamber 8, the water in the discharge port 9 and the discharge pipe 7 instantaneously reversely flows, and the expansion chamber 8 , The impact of the vane 5 may be caused by the compression of water by the rotation of the rotor 3 or the liquid hammer phenomenon, and the vane 5 may be broken.

For this reason, the material constituting the rotary vane pump 1 requires strength including the vane 5 and is mainly a metal material. Therefore, lubricating oil was needed.

However, in the rotary vane pump 1 using lubricating oil, there is a problem of polluting the environment because water mixed with oil is discharged at the time of priming.

Accordingly, a priming device using a rotary vane pump 1 incorporating a self-lubricating vane 5 such as a carbon material has been proposed. Rotary vane pump 1 using such a self-lubricating vane 5
Since the vane 5 has a self-lubricating property, no lubricating oil is required.

However, in the priming device in which the vane 5 is made of a weak material such as a carbon material having self-lubricating properties, the rotary vane pump 1
If water enters the vane 5, the vane 5 may be destroyed due to the compression of water or the liquid hammer phenomenon or the like. Therefore, it is necessary to add protection means for the vane 5.

FIG. 11 shows the structure of a priming device of this type of conventional water supply pump to which a protection means for the self-lubricating vane 5 is added.

The water supply pump 10 discharges water supplied from a water suction port 11 through a discharge port 13 of a discharge valve 12.

A priming device 14 for priming the water supply pump 10 has a structure mainly including the rotary vane pump 1. The rotary vane pump 1 is connected to a discharge passage 15 of a water supply pump 10 by a pipe 6. A strainer 16 and a steam separator 17 having a float valve 30 that closes a passage on the discharge side when water flows in are connected in the middle of the pipe 6, and the pipe 6 is connected to the water supply pump 10 through a check valve 18. It is connected to the discharge passage 15. The drain passage 15 is opened by a negative pressure caused by suction of the rotary vane pump 1 during priming, closed when the rotary vane pump 1 is stopped, and flows into the rotary vane pump 1 when the suction port 11 becomes positive pressure. Is provided with a diaphragm-type water stop valve 19 for preventing the water leakage.

In such a priming device 14, a steam separator 17 is provided in the middle of the pipe 6, and even if priming water enters the pipe 6, the priming water is separated by the steam separator 17 and supplied to the rotary vane pump 1. The water does not flow in, so that the vane 5 can be prevented from being destroyed due to the compression of water or the liquid hammer phenomenon.

[0015]

However, FIG.
In the priming device 14 of the water supply pump having the structure shown in FIG. 1, the steam-water separator 17 is required, so that the device becomes large-scale. In addition, there is a problem that the steam-water separator 17 and the like hinder the complete priming operation. there were.

An object of the present invention is to provide a priming device for a water supply pump that does not require a steam separator.

[0017]

SUMMARY OF THE INVENTION The present invention provides a priming device for a water supply pump that drives a rotary vane pump using a self-lubricating vane, discharges air in the water supply pump to the outside, and primes the water supply pump. Is targeted for improvement.

In the priming device for a water supply pump according to the present invention, an air assist portion for sucking outside air is provided at any part from a suction side of the rotary vane pump to a discharge port of the rotary vane pump. And

In the present invention, the suction side of the rotary vane pump means a portion from the outlet of the water supply pump to the inlet of the rotary vane pump.

As described above, when an air assist portion for sucking outside air is provided in any portion from the suction side of the rotary vane pump to the discharge port of the rotary vane pump, a certain amount of air is supplied from the air assist portion to the rotary vane pump. Therefore, when priming water enters the expansion chamber, the negative pressure of the expansion chamber drops. Therefore, when the discharge port of the rotary vane pump communicates with the expansion chamber, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. Further, since air is present in the expansion chamber, the impact force of water applied to the vane can be reduced due to the damper effect of the air, thereby preventing the self-lubricating vane from being broken.

Accordingly, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator is not required,
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized.

Further, the priming device for a water supply pump according to the present invention is characterized in that an air assist portion for sucking outside air is provided on the suction side of the rotary vane pump. In this way, when the air assist section for sucking outside air is provided on the suction side of the rotary vane pump, a certain amount of air enters the expansion chamber of the rotary vane pump from the air assist section, so that priming water enters the expansion chamber. At this time, the negative pressure in the expansion chamber drops. Therefore, when the discharge port of the rotary vane pump communicates with the expansion chamber, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. Further, since air is present in the expansion chamber, the impact force of water applied to the vane can be reduced due to the damper effect of the air, thereby preventing the self-lubricating vane from being broken.

Therefore, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator becomes unnecessary,
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized. Furthermore, providing an air assist portion on the suction side of the rotary vane pump has the advantage that the present invention can be implemented without processing the rotary vane pump.

In this case, the air assist section may have a structure provided with a small hole for outside air suction provided on the suction side of the rotary vane pump.

In particular, according to the air assist portion having the small holes for intake of outside air, the air assist portion can be easily provided at low cost.

The air assist section is provided with a small hole for outside air suction provided on the suction side of the rotary vane pump, and the small hole for outside air suction is closed at the time of exhaustion from the water supply pump. And a valve that opens a small hole.

As described above, by providing a valve that closes the small hole for outside air intake at the time of exhaustion from the water supply pump and opens the small hole for outside air suction with water at the completion of priming, the rotary vane pump is provided only when necessary. The outside air can be inhaled. Therefore, when only the air is sucked in by the rotary vane pump, the valve does not open and there is no air leakage, so that the degree of vacuum in the rotary vane pump can be prevented from lowering.

Further, the priming device for a water supply pump according to the present invention is characterized in that an air assist portion for sucking outside air is provided at a discharge port of the rotary vane pump.

By providing an air assist section for sucking outside air at the discharge port of the rotary vane pump, priming water enters the expansion chamber of the rotary vane pump, and when the discharge port communicates with the expansion chamber by rotation of the rotor, the air is released. Since a certain amount of air enters the expansion chamber from the assist portion, the negative pressure in the expansion chamber decreases. For this reason, when the discharge port of the rotary vane pump communicates with the expansion chamber, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. Further, since there is air in the expansion chamber, the impact force of water applied to the vane due to the damper effect of the air can be reduced. For this reason, breakage of the self-lubricating vane can be prevented.

Therefore, even in the priming device of the water supply pump having such a structure, the steam-water separator becomes unnecessary even if a rotary vane pump using a self-lubricating vane is used.

In particular, if an air assist portion is provided at the discharge port of the rotary vane pump, air enters the rotary vane pump only when the discharge port communicates with the expansion chamber. There is an advantage that the decrease of the amount is small.

In this case, the air assist section may have a structure provided with a small hole for intake of outside air provided at the discharge port of the rotary vane pump.

In particular, according to the air assist portion having the small hole for sucking outside air, the air assist portion can be easily provided at low cost.

The air assist section is provided with a small hole for intake of outside air provided at a discharge port of the rotary vane pump, and the outside air suction port is configured to prevent discharge of water from the small hole for outside air suction and to perform only suction of outside air. And a check valve for controlling the small hole.

As described above, when the check valve for controlling the small hole for outside air suction is provided so as to prevent the discharge of water from the small hole for outside air suction and to perform only the suction of outside air, the small hole for outside air suction during priming is provided. Water can be prevented from being discharged from the holes.

In the priming device for a water supply pump according to the present invention, an air assist portion for sucking outside air is provided in a pump casing before a discharge port of the rotary vane pump.

When the air assist section is provided in the pump casing before the discharge port of the rotary vane pump, a certain amount of air from the air assist section enters the expansion chamber of the rotary vane pump. When entering, the negative pressure in the expansion chamber drops. Therefore, when the discharge port of the rotary vane pump communicates with the expansion chamber, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. Further, since air is present in the expansion chamber, the impact force of water applied to the vane can be reduced due to the damper effect of the air, thereby preventing the self-lubricating vane from being broken.

Therefore, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator becomes unnecessary, and
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized. Furthermore, providing the air assist section in the pump casing before the discharge port of the rotary vane pump has the advantage that the present invention can be implemented by processing a single rotary vane pump.

In this case, the air assist section may have a structure provided with a small hole for external air suction provided in the pump casing before the discharge port of the rotary vane pump.

In particular, according to the air assist portion including the small holes for intake of outside air, the air assist portion can be formed by processing the rotary vane pump alone, and the air assist portion can be easily provided at low cost.

[0041]

FIG. 1 shows a first embodiment of a priming device 14 for a water supply pump according to the present invention. In addition, the part corresponding to FIG.
The same reference numerals are given.

The priming device 14 of this embodiment is characterized in that an air assist section 20 for sucking outside air is provided on the suction side of the rotary vane pump 1 using a self-lubricating vane 5 made of carbon or the like. In this case, the air assist unit 20 is formed by a small hole 21 for outside air suction provided in the pipe 6 on the suction side of the rotary vane pump 1.

Next, the operation of the priming device 14 will be described in detail with reference to FIGS.

When the rotary vane pump 1 is driven to perform a priming operation, initially only air is sucked and discharged from the water supply pump 10, but eventually the water 22 is also sucked as shown in FIG. become. At this time, the outside air 2 is supplied from the outside air intake small hole 21 provided in the pipe 6.
3 also enters the expansion chamber 8 in the rotary vane pump 1 by a predetermined amount. For this reason, the negative pressure in the expansion chamber 8 decreases.

Therefore, as shown in FIG.
Rotates to discharge port 9 of the rotary vane pump 1.
When water communicates with the expansion chamber 8, water 2
The amount and speed of the back flow of the fluid 2 into the expansion chamber 8 can be suppressed. Further, since the air 23 is present in the expansion chamber 8, the impact force of water applied to the self-lubricating vane 5 by the damper effect of the air 23 can be reduced. Therefore, breakage of the self-lubricating vane 5 can be prevented.

Therefore, in the priming device 14 of the water supply pump having such a structure, even if the rotary vane pump 1 using the self-lubricating vane 5 is used, the steam-water separator is not required.

In particular, according to the air assist unit 20 including the small holes 21 for sucking outside air as in this embodiment, the air assist unit 20 can be easily provided at low cost.

In the case of this embodiment, since the small holes 21 for sucking outside air are provided on the suction side of the rotary vane pump 1, the degree of vacuum in the rotary vane pump 1 is reduced due to air leakage. For this reason, the outside air intake small holes 21 have a diameter that minimizes the reduction in the degree of vacuum. The diameter of the small hole 21 for intake of outside air depends on the displacement of the rotary vane pump 1.
When the exhaust capacity is large, the value is appropriately set larger, and when the exhaust capacity is small, the value is set smaller. The adjustment of the amount of air sucked into the small hole 21 for intake of outside air can be performed by adjusting the diameter of the small hole 21 and the length of the small hole 21.

Next, in the case of the conventional example in which the air assist section 20 for sucking outside air is not provided on the suction side of the rotary vane pump 1, the air assist section 20 is provided as in the present embodiment, and water is supplied into the rotary vane pump 1. A comparison test result of the pressure at the discharge port 9 when the gas flows in will be described.

FIGS. 3A and 3B show the pressure of the discharge port 9 in the conventional example without the air assist unit 20 when the rotation speed of the rotary vane pump 1 is 1000 rpm and in the present example with the air assist unit 20. 3 shows the results of a comparative experiment.

FIG. 3A shows the pressure at the discharge port 9 of the rotary vane pump 1 in the conventional example without the air assist unit 20, and FIG. 3B shows the discharge of the rotary vane pump 1 in the present example with the air assist unit 20. The pressure at port 9 is shown.

As is clear from the drawing, according to the present embodiment having the air assist section 20, the pressure at the discharge port 9 is clearly lower than in the conventional example without the air assist section 20.

FIGS. 4A and 4B show the pressure of the discharge port 9 in the conventional example without the air assist unit 20 when the rotation speed of the rotary vane pump 1 is 2800 rpm, and in the present example with the air assist unit 20. 3 shows the results of a comparative experiment.

FIG. 4A shows the pressure at the discharge port 9 of the rotary vane pump 1 in the conventional example without the air assist unit 20, and FIG. 4B shows the discharge of the rotary vane pump 1 in the present example with the air assist unit 20. The pressure at port 9 is shown.

Also in this case, as is clear from the drawing, according to the present embodiment having the air assist unit 20, the pressure at the discharge port 9 is clearly lower than in the conventional example without the air assist unit 20.

FIGS. 5A and 5B show a second embodiment of the priming device 14 of the water supply pump according to the present invention. Note that parts corresponding to those in FIG. 1 described above are denoted by the same reference numerals.

In the priming device 14 of this embodiment, the air assist unit 20 for sucking outside air is provided on the suction side of the rotary vane pump 1 using the self-lubricating vane 5 made of carbon or the like. It is similar to one example. The air assist unit 20 of the present embodiment is provided with a small hole 21 for external air suction provided on the suction side of the rotary vane pump 1.
And a reed valve 24 that closes the small air intake hole 21 when the water supply pump 10 is evacuated and opens the small air intake hole 21 by the flow of the water 22 when the priming is completed.

In such a priming device 14, FIG.
(A) As shown in FIG.
When the air is being sucked, the reed valve 24 closes the small hole 21 for sucking outside air and does not suck air. Therefore, when the rotary vane pump 1 exhausts the water from the water supply pump 10, the reed valve 24 does not open and there is no air leakage, so that the degree of vacuum in the rotary vane pump 1 can be prevented from lowering.

When the priming is completed, as shown in FIG. 5 (B), the flow of water 22 causes the reed valve 24 to fall to open the small hole 21 for intake of outside air, and the air 23 as outside air enters the rotary vane pump 1. Be inspired. For this reason, the negative pressure in the expansion chamber 8 decreases. Therefore, when the rotor 3 rotates and the discharge port 9 of the rotary vane pump 1 communicates with the expansion chamber 8, the amount and speed of the water 22 flowing backward from the discharge port 9 to the expansion chamber 8 can be suppressed. Further, since the air 23 is present in the expansion chamber 8, the impact force of water applied to the self-lubricating vane 5 by the damper effect of the air 23 can be reduced. Therefore, breakage of the self-lubricating vane 5 can be prevented.

FIG. 6 shows a third embodiment of the priming device 14 of the water supply pump according to the present invention. Note that parts corresponding to those in FIG. 1 described above are denoted by the same reference numerals.

The priming device 14 of this embodiment is characterized in that an air assist section 20 for sucking outside air is provided at the discharge port 9 of the rotary vane pump 1 using a self-lubricating vane 5 made of carbon or the like. I do.
In this case, the air assist unit 20 is provided with the small hole 2 for outside air suction provided in the discharge port 9 of the rotary vane pump 1.
1.

As described above, the air assist unit 21 for sucking outside air into the discharge port 9 of the rotary vane pump 1
Is provided, the priming water 22 is supplied to the rotary vane pump 1
When the discharge port 9 communicates with the expansion chamber 8 by the rotation of the rotor 3 as shown in FIG. 7, a certain amount of air 23 flows from the small air intake hole 21 of the air assist unit 20.
Enters the expansion chamber 8, the negative pressure in the expansion chamber 8 decreases.
Therefore, when the discharge port 9 of the rotary vane pump 1 communicates with the expansion chamber 8, water 22
The amount and speed of the backflow into the expansion chamber 8 can be suppressed. Also,
Since air is present in the expansion chamber 8, the impact force of water applied to the self-lubricating vane 5 can be reduced by the damper effect of the air 23. Therefore, breakage of the self-lubricating vane 5 can be prevented.

Accordingly, even in the priming device 14 of the water supply pump having such a structure, even if the rotary vane pump 1 using the self-lubricating vane 5 is used, the steam-water separator becomes unnecessary.

According to the air assist unit 20 including the small holes 21 for intake of outside air as in this embodiment, the air assist unit 20 can be easily provided at low cost.

In particular, when the air assist section 20 is provided in the discharge port 9 of the rotary vane pump 1, air 23 enters the rotary vane pump 1 only when the discharge port 9 communicates with the expansion chamber 8. There is an advantage that the degree of vacuum of the rotary vane pump 1 is less reduced.

FIG. 8 shows a fourth embodiment of the priming device 14 of the water supply pump according to the present invention. Note that parts corresponding to those in FIG. 1 described above are denoted by the same reference numerals.

In the priming device 14 of this embodiment, the point that the air assist section 20 for sucking outside air is provided at the discharge port 9 of the rotary vane pump 1 using the self-lubricating vane 5 made of carbon or the like is described above. This is the same as the third example. The air assist unit 20 of the present occasion is provided with a small hole 21 for external air suction provided in the discharge port 9 of the rotary vane pump 1 and prevents only water 22 from being discharged from the small hole 21 for external air suction and performs only air suction. And the check valve 25 for controlling the small hole 21 for intake of outside air. The check valve 25 includes a valve box 26 surrounding the small hole 21 for sucking outside air, a valve hole 27 opened at an end of the valve box 26,
It comprises a ball valve body 28 that closes the valve hole 27 in the valve box 26, and a spring 29 that urges the ball valve body 28 against the valve hole 27.

In such a priming device 14, when the priming water 22 enters the expansion chamber 8 of the rotary vane pump 1 and the discharge port 9 communicates with the expansion chamber 8 by the rotation of the rotor 3 as shown in FIG. Due to the negative pressure in the chamber 8, the ball valve body 28 of the air assist unit 20
Is pulled away from the valve hole 27 to open the check valve 25, a certain amount of air 23 enters the expansion chamber 8 from the outside air suction small hole 21, and the negative pressure of the expansion chamber 8 decreases. . Therefore, when the discharge port 9 of the rotary vane pump 1 communicates with the expansion chamber 8, the amount and speed of the water 22 flowing backward from the discharge port 9 to the expansion chamber 8 can be suppressed. Further, since air is present in the expansion chamber 8, the impact force of water applied to the self-lubricating vane 5 by the damper effect of the air 23 can be reduced. Therefore, breakage of the self-lubricating vane 5 can be prevented.

According to the check valve 25, it is possible to prevent the water 22 from being discharged from the small hole 21 for sucking outside air during priming.

FIG. 9 shows a fifth embodiment of the priming device 14 of the water supply pump according to the present invention. Note that parts corresponding to those in FIG. 1 described above are denoted by the same reference numerals.

In the priming device 14 of this embodiment, an air assist unit 20 for sucking outside air is provided in the pump casing 2 in front of the discharge port 9 of the rotary vane pump 1 using a self-lubricating vane 5 made of carbon or the like. It is characterized by the following. In this case, the air assist unit 20
Is formed by an outside air intake small hole 21 provided in the pump casing 2 before the discharge port 9 of the rotary vane pump 1.

Next, the operation of the priming device 14 will be described in detail.

When the rotary vane pump 1 is driven to perform a priming operation, initially only air is sucked and discharged from the water supply pump 10, but eventually water 22 is also sucked up. At this time, a certain amount of air 23, which is the outside air, also enters the expansion chamber 8 in the rotary vane pump 1 through the small outside air intake hole 21 provided in the pump casing 2 before the discharge port 9. For this reason, the negative pressure in the expansion chamber 8 decreases.

Therefore, when the rotor 3 rotates and the discharge port 9 of the rotary vane pump 1 communicates with the expansion chamber 8, the amount and speed of the water 22 flowing backward from the discharge port 9 to the expansion chamber 8 can be suppressed. . Further, air 2 is contained in the expansion chamber 8.
3, the impact force of water applied to the self-lubricating vane 5 by the damper effect of the air 23 can be reduced. Therefore, breakage of the self-lubricating vane 5 can be prevented.

Therefore, in the priming device 14 of the water supply pump having such a structure, even if the rotary vane pump 1 using the self-lubricating vane 5 is used, the steam-water separator is not required, and the size of the device can be reduced. And cost can be reduced. In addition, if the self-lubricating vane 5 can be prevented from being broken, the thickness of the vane 5 can be reduced, so that the rotary vane pump 1 can be downsized. Further, when the air assist unit 20 is provided in the pump casing 2 before the discharge port 9 of the rotary vane pump 1, there is an advantage that the present invention can be implemented by processing a single rotary vane pump.

In particular, according to the air assist unit 20 including the small holes 21 for sucking outside air as in this embodiment, the air assist unit 20 can be formed by processing a rotary vane pump alone, and the air assist unit 20 can be easily formed at low cost. Can be provided.

The self-lubricating vane 5 is not limited to carbon, but may be a resin such as a polyimide resin.

[0078]

In the priming device for a water supply pump according to the present invention, an air assist portion for sucking outside air is provided in any portion from the suction side of the rotary vane pump to the discharge port of the rotary vane pump.
Since a certain amount of air from the air assist section enters the expansion chamber of the rotary vane pump, the negative pressure of the expansion chamber drops when priming water enters the expansion chamber, and thus the discharge port of the rotary vane pump is connected to the expansion chamber. When communicating with the water, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. In addition, since there is air in the expansion chamber, the impact force of water applied to the vane can be reduced by the damper effect of the air, so that the self-lubricating vane can be prevented from being broken.

Therefore, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator becomes unnecessary,
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized.

Further, in the priming device for a water supply pump according to the present invention, an air assist portion for sucking outside air is provided on the suction side of the rotary vane pump, so that when priming water enters the expansion chamber of the rotary vane pump, Since a certain amount of air enters the expansion chamber from the air assist unit, the negative pressure of the expansion chamber drops, and when the discharge port of the rotary vane pump communicates with the expansion chamber, water flows from the discharge port to the expansion chamber. The amount and speed of the backflow to the air can be suppressed. Further, according to this priming device, since air is present in the expansion chamber, the impact force of water applied to the vane due to the damper effect of the air can be reduced, thereby preventing the self-lubricating vane from being broken.

Therefore, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator is not required.
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized.

In this case, if the air assist portion is formed by small holes for outside air suction provided on the suction side of the rotary vane pump, the air assist portion can be easily provided at low cost.

Further, the air assist section closes the small hole for external air suction provided on the suction side of the rotary vane pump and the small hole for external air suction when exhausting water from the water supply pump, and uses the water when the priming is completed. And a valve for opening a small hole, the presence of the valve allows the outside air to be sucked into the rotary vane pump only when necessary. Therefore, when only the air is sucked by the rotary vane pump, the valve does not open and there is no air leakage, so that it is possible to prevent a decrease in the degree of vacuum in the rotary vane pump.

In the priming device for a water supply pump according to the present invention, an air assist portion for sucking outside air is provided at the discharge port of the rotary vane pump. When the discharge port communicates with the expansion chamber due to the rotation, a certain amount of air enters the expansion chamber from the air assist unit, so that the negative pressure of the expansion chamber is reduced. Therefore, the discharge port of the rotary vane pump communicates with the expansion chamber. When this is done, the amount and speed of water flowing backward from the discharge port to the expansion chamber can be suppressed. Further, according to this priming device, since air is present in the expansion chamber, the impact force of water applied to the vane due to the damper effect of the air can be reduced, thereby preventing the self-lubricating vane from being broken.

Therefore, even in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator becomes unnecessary,
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced.

In particular, if an air assist section is provided at the discharge port of the rotary vane pump, air enters the rotary vane pump only when the discharge port communicates with the expansion chamber. There is an advantage that the degree of vacuum is hardly reduced.

In this case, if the air assist portion is formed by a small hole for outside air suction provided in the discharge port of the rotary vane pump, the air assist portion can be easily provided at low cost.

Further, an air assist unit is provided with a small hole for intake of outside air provided at a discharge port of the rotary vane pump, and the outside air is restricted so as to prevent discharge of water from the small hole for intake of outside air and to only suck outside air. When the check valve is formed by the check valve for controlling the suction hole, the presence of the check valve can prevent water from being discharged from the outside air suction hole at the time of priming.

In the priming device for a water supply pump according to the present invention, the pump casing provided before the discharge port of the rotary vane pump is provided with an air assist section for sucking outside air, so that a certain amount of air is supplied from the air assist section. Enters the expansion chamber of the rotary vane pump, so that when the priming water enters the expansion chamber, the negative pressure of the expansion chamber drops, and when the discharge port of the rotary vane pump communicates with the expansion chamber, the discharge port The amount and speed at which water flows back into the expansion chamber can be suppressed. In addition, since there is air in the expansion chamber, the impact force of water applied to the vane can be reduced by the damper effect of the air, so that the self-lubricating vane can be prevented from being broken.

Therefore, in the priming device for a water supply pump having such a structure, even if a rotary vane pump using a self-lubricating vane is used, a steam-water separator is not required, and
Complete priming operation can be performed, the size of the device can be reduced, and cost can be reduced. Further, when the self-lubricating vane can be prevented from being broken, the thickness of the vane can be reduced, and therefore, the rotary vane pump can be downsized. Furthermore, providing the air assist section in the pump casing before the discharge port of the rotary vane pump has the advantage that the present invention can be implemented by processing a single rotary vane pump.

In particular, according to the air assist portion having the small holes for sucking outside air, the air assist portion can be formed by processing the rotary vane pump alone, and the air assist portion can be easily provided at low cost.

[Brief description of the drawings]

FIG. 1 is a longitudinal sectional view showing a first example of an embodiment of a priming device for a water supply pump according to the present invention.

FIGS. 2A and 2B are explanatory diagrams illustrating the operation of the priming device shown in FIG. 1;

3 (A) and 3 (B) show the results of a comparative experiment of the pressure at the discharge port in the conventional example without the air assist part when the rotation speed of the rotary vane pump is 1000 rpm and in the present example with the air assist part. FIG.

4 (A) and 4 (B) show the results of a comparison experiment of the pressure at the discharge port between the conventional example without the air assist portion and the present example with the air assist portion when the rotation speed of the rotary vane pump is 2800 rpm. FIG.

FIGS. 5A and 5B are longitudinal sectional views showing the operation of a second example of the embodiment of the priming device of the water supply pump according to the present invention.

FIG. 6 is a longitudinal sectional view showing a third example of an embodiment of a priming device for a water supply pump according to the present invention.

FIG. 7 is a longitudinal sectional view showing the operation of the priming device shown in FIG.

FIG. 8 is a longitudinal sectional view showing a fourth example of an embodiment of a priming device for a water supply pump according to the present invention.

FIG. 9 is a longitudinal sectional view showing a fifth example of an embodiment of a priming device for a water supply pump according to the present invention.

FIGS. 10A and 10B are explanatory diagrams of the operation of a rotary vane pump in a conventional priming device.

FIG. 11 is a vertical sectional side view of a main part of a priming device of a conventional water supply pump.

[Explanation of symbols]

 Reference Signs List 1 rotary vane pump 2 pump case 3 rotor 4 groove 5 vane 6 pipe 7 discharge pipe 8 expansion chamber 9 discharge port 10 water supply pump 11 water inlet 12 discharge valve 13 discharge port 14 priming device 15 discharge passage 16 strainer 17 gas-water separator 18 reverse Stop valve 19 Diaphragm type water stop valve 20 Air assist unit 21 Small hole for outside air intake 22 Water 23 Air 24 Reed valve 25 Check valve 26 Valve box 27 Valve hole 28 Ball valve element 29 Spring 30 Float valve

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-61-171894 (JP, A) JP-A-54-24307 (JP, A) JP-A-8-135586 (JP, A) JP-A-2- 294593 (JP, A) Japanese Utility Model 1987-197786 (JP, U) Japanese Utility Model 1987-156180 (JP, U) Japanese Utility Model 48-41683 (JP, Y1) Japanese Utility Model Utility Model 39-15764 (JP, Y1) (58) Field surveyed (Int.Cl. ⁷ , DB name) F04D 9/04 F04C 2/344 F04C 25/02 F04C 18/344

Claims (9)

(57) [Claims] 1. A priming device for a water supply pump that drives a rotary vane pump using a self-lubricating vane, discharges air in the water supply pump to the outside, and primes the water supply pump, wherein a suction side of the rotary vane pump is provided. A priming device for a water supply pump, wherein an air assist portion for sucking outside air is provided in any portion from the outlet to the discharge port of the rotary vane pump. 2. A priming device for a water supply pump that drives a rotary vane pump using a self-lubricating vane, discharges air in the water supply pump to the outside, and primes the water supply pump, wherein a suction side of the rotary vane pump is provided. A priming device for a water supply pump, further comprising an air assist unit for sucking outside air. 3. The priming device for a water supply pump according to claim 2, wherein the air assist section has a structure provided with a small hole for outside air suction provided on a suction side of the rotary vane pump. . 4. The air assist section closes the small hole for outside air suction provided on the suction side of the rotary vane pump, and closes the small hole for outside air suction at the time of exhaustion from the water supply pump, so that the water at the completion of priming is used. 3. A valve for opening said small hole for intake of outside air.
A priming device for a water supply pump according to item 1. 5. A priming device for a water supply pump that drives a rotary vane pump using a self-lubricating vane, discharges air in the water supply pump to the outside, and primes the water supply pump, wherein a discharge port of the rotary vane pump is provided. A priming device for a water supply pump, further comprising an air assist unit for sucking outside air. 6. The air assist section has a structure provided with a small hole for intake of outside air provided at a discharge port of the rotary vane pump.
A priming device for a water supply pump according to item 1. 7. The air assist unit according to claim 1, further comprising: a small hole for external air suction provided in a discharge port of the rotary vane pump; and a device for preventing discharge of water from the small hole for external air suction and performing only air suction. The priming device for a water supply pump according to claim 5, wherein the priming device is formed by a check valve that controls the small hole for intake of outside air. 8. A priming device for a water supply pump that drives a rotary vane pump using a self-lubricating vane, discharges air in the water supply pump to the outside, and primes the water supply pump, wherein a discharge port of the rotary vane pump is provided. A priming device for a water supply pump, wherein an air assist portion for sucking outside air is provided in an earlier pump casing. 9. The priming device for a water supply pump according to claim 2, wherein the air assist portion has a structure provided with a small hole for outside air suction provided in the pump casing.