JPH0317194U

JPH0317194U -

Info

Publication number: JPH0317194U
Application number: JP7521189U
Authority: JP
Priority date: 1989-06-27
Filing date: 1989-06-27
Publication date: 1991-02-20

Description

[Brief explanation of drawings]

第１図は本考案の第１実施例を示す側面図、第
２図は一方の切換弁の切換状態を示す説明図、第
３図は他方の切換弁の切換状態を示す説明図、第
４図は第２実施例を示す側面図である。１……羽根車、１Ａ……羽根車の吸込部、３…
…吸込ベルマウス、８……貫通孔、９……空気流
入管、１０……一方の切換弁、１０ａ……受圧ポ
ート、１１……圧力検知管、１１ｘ……開閉始端
、１１ｙ……開放終端、１２……他方の切換弁、
１２ａ……受圧ポート、１４……高圧空気供給源
、３０……空気流入・遮断装置、ＬＷＬ……最低
水位レベル。 Fig. 1 is a side view showing the first embodiment of the present invention, Fig. 2 is an explanatory diagram showing the switching state of one switching valve, Fig. 3 is an explanatory diagram showing the switching state of the other switching valve, and Fig. 4 is an explanatory diagram showing the switching state of the other switching valve. The figure is a side view showing the second embodiment. 1... Impeller, 1A... Suction part of impeller, 3...
...Suction bell mouth, 8...Through hole, 9...Air inflow pipe, 10...One switching valve, 10a...Pressure receiving port, 11...Pressure detection tube, 11x...Opening/closing start end, 11y...Opening end , 12...the other switching valve,
12a...Pressure receiving port, 14...High pressure air supply source, 30...Air inflow/blocking device, LWL...Lowest water level.

Claims

[Scope of Claim for Utility Model Registration] (1) In a vertical shaft pump in which an impeller is disposed above the lowest water level below which air will be sucked in if the water level of the suction bell mouth is submerged, the suction portion of the impeller is A through hole leading to the outside is formed, and an air inflow pipe with a switching valve that can be switched between two positions, an air inflow position and a blocking position, is connected to this through hole, and the opening start end is at the minimum water level or A pressure detection tube is located near the pressure detection tube, and the open end is connected to the pressure receiving port of the other switching valve. a first switching position in which the one switching valve is switched to an air cutoff position by communicating with a high-pressure air supply source; and a first switching position in which the pressure receiving port of the one switching valve is communicated with the atmosphere and the one switching valve is switched to an air inflow position. A vertical shaft pump characterized in that it is provided with an air inflow/blocking device configured to be switched to a second switching position. (2) In a vertical shaft pump in which an impeller is arranged below the lowest water level below which air will be sucked in if the water level of the suction bell mouth is submerged, the suction part of the impeller forms a through hole that communicates with the outside. An air inflow pipe with a switching valve that can be switched between two positions, an air inflow position and a blocking position, is connected to this through hole, and the opening start end is located at or near the lowest water level level, and the opening A pressure detection tube is provided whose terminal end is connected to the pressure receiving port of the other switching valve, and the other switching valve connects the pressure receiving port of one switching valve to a high-pressure air supply source in response to pressure changes in the pressure detection tube. , a first switching position in which one switching valve is switched to an air cutoff position, and a second switching position in which the pressure receiving port of the one switching valve is communicated with the atmosphere and one switching valve is switched to an air inflow position. A vertical shaft pump characterized by being equipped with an air inflow/blocking device configured as follows.