JP2854764B2 - Self-priming pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION The present invention relates to a self-priming pump.
In particular, the present invention relates to a self-priming pump in which, for example, water discharged from an outlet of a pump chamber into a gas-water separation chamber is returned to a pump chamber through a return hole, thereby having a self-priming function.

[0002]

2. Description of the Related Art An example of this type of self-priming pump is disclosed in, for example, JP-A-59-103879. According to this conventional technique, the plunger is opened during the self-priming operation, and the water discharged from the outlet of the pump chamber to the air separation chamber (water-water separation chamber) is returned to the pump chamber at the same time as the air in the water passage is discharged. During operation, the pressure loss is reduced by closing the plunger.

[0003]

In this type of self-priming pump, it is necessary to discharge the air accumulated in the water passage during the self-priming operation. However, when the capacity of the discharge-side piping system becomes large, the amount of discharged air becomes large. Therefore, there is a problem that the self-priming operation time becomes long. Therefore, a main object of the present invention is to provide a self-priming pump that can reduce the self-priming operation time.

[0004]

According to the present invention, there is provided a pump chamber having an inlet and an outlet, in which an impeller is housed, an inlet for taking in water discharged from the outlet, and a water pipe.
A steam / water separation chamber having a discharge port connected to a passage, a return hole communicating the pump chamber and the steam / water separation chamber, provided in the steam / water separation chamber
And a fixed water level sensor for detecting the water level in the air / water separation chamber , and a water level sensor
The self-priming pump includes an exhaust valve that is closed when a water level equal to or higher than a predetermined level is detected .

[0005]

When the switch of the pump is turned on, the self-priming operation is started, and the air accumulated in the water passage is discharged from the exhaust valve. When the water level in the steam-water separation chamber rises and the water level sensor detects a predetermined water level, the exhaust valve is closed in response to the output of the water level sensor, and leakage from the exhaust valve during the pumping operation is prevented.

[0006]

According to the present invention, since it is only necessary to discharge the air accumulated in the water passage to the exhaust valve, the amount of exhaust air can be reduced and the self-priming operation time can be shortened. Also movable
Since a fixed type water level sensor with no
There is also concern that reliability may be reduced due to the provision of a position sensor
Absent. The above and other objects, features and advantages of the present invention will become more apparent from the following detailed description of embodiments with reference to the drawings.

[0007]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS Referring to FIG. 1, a self-priming pump 10 of this embodiment has a first casing 12, a second casing 14, and a separation plate interposed between the first casing 12 and the second casing 14. 16 inclusive. A pump chamber 18 is formed inside the first casing 12, and an impeller 20 connected to a rotating shaft of a motor (not shown) is housed in the pump chamber 18. A pump chamber inlet 22 is formed at the center of the upper surface of the pump chamber 18 (the center of the separation plate 16).
A pump chamber outlet 24 is formed at the periphery of the pump 8.

A pump chamber outlet 24 is provided at a peripheral portion of the separation plate 16.
An inlet 26 communicating with the nozzle 26 is formed, and rises upward from the inlet 26 to form a substantially cylindrical ejection nozzle 28. At least one return hole 32 that connects the pump chamber 18 to a steam-water separation chamber 30 described later is formed in the peripheral portion of the separation plate 16. Inside the second casing 14, a steam-water separation chamber 30 is formed. A suction port 34 and a discharge port 36 are formed on the upper surface of the steam separation chamber 30. The suction port 34 and the pump chamber inlet 22 communicate with each other through a cylindrical portion 38. Is connected. The electrodes 44 a and 44 b of the water level sensor 42 are provided inside the steam-water separation chamber 30, and an exhaust valve 46 is provided near the discharge port 36 of the drain pipe 38. Electrode 44a
And 44b and the exhaust valve 46 are each connected to a sensor circuit 48, and a voltage is applied to the electrodes 44a and 44b by the sensor circuit 48.

In operation, when a switch (not shown) of the self-priming pump 10 is turned on, the exhaust valve 46 is opened, the impeller 20 is rotated by a motor (not shown), and the self-priming operation is started. . That is, the pump chamber 1
Water and air are mixed in 8, and the mixed water and air are discharged from the pump chamber outlet 24 through the ejection nozzle 28 into the steam-water separation chamber 30. The air discharged into the steam separation chamber 30 is directly sent out from the discharge port 36 and discharged through the exhaust valve 46. On the other hand, the water discharged into the steam separation chamber 30 is returned to the pump chamber 18 through the return hole 32.
The water returned to the pump chamber 18 is mixed with the air again, and is discharged from the pump chamber outlet 24 through the jet nozzle 28 into the steam-water separation chamber 30. While repeating such an operation, water starts to be sucked in from the suction port 34, and the water level in the steam-water separation chamber 30 rises. The water level in the steam-water separation chamber 30 is
When the voltage reaches a and 44b, a closed circuit is formed between the electrodes 44a and 44b, and a current flows through the closed circuit.
The sensor circuit 48 detects the current flowing in the closed circuit and closes the exhaust valve 46 at the same time. When the inside of the steam separator 30 becomes full, the self-priming operation ends and the pumping operation starts.

According to this embodiment, the air collected in the water passage during the self-priming operation is supplied to the exhaust valve 4 provided in the middle of the drain pipe 38.
6 so that the drainage line 38
The amount of exhaust air can be reduced as compared with the prior art that is discharged from the tip of the vehicle, and the self-priming operation time can be reduced. In addition, fixed
Since the fixed water level sensor 42 is used, it is practically sufficient.
Reliability can be obtained.

[Brief description of the drawings]

FIG. 1 is an illustrative view showing one embodiment of the present invention;

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 10 ... Self-priming pump 20 ... Impeller 16 ... Separation plate 18 ... Pump chamber 22 ... Pump chamber inlet 24 ... Pump chamber outlet 28 ... Squirting nozzle 30 ... Gas-water separation chamber 32 ... Reflux hole 38 ... Drain pipe 42 ... Water level Sensors 44a, 44b ... electrodes 46 ... exhaust valves

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-48-85201 (JP, U) (58) Fields investigated (Int. Cl. ⁶ , DB name) F04D 9/02 102 F04D 9/02 101

Claims (1)

(57) [Claims] A pump chamber having an inlet and an outlet, and an impeller housed therein; an inlet for taking in water discharged from the outlet; and a water pipe.
A steam / water separation chamber having a discharge port connected to a passageway, a return hole communicating the pump chamber and the steam / water separation chamber, a water level provided in the steam / water separation chamber, and detecting a water level in the steam / water separation chamber. A fixed water level sensor, and a water level sensor provided in the water distribution pipe,
Self-priming pump with an exhaust valve that closes when the water level is detected .