JPS5835300A - Forced feed pump apraratus - Google Patents

Abstract

PURPOSE:To enable remaining air in a siphon pipe to be ejected for a short time by providing a discharge valve and a exhaust branch in the siphon pipe without necessitating other auxiliaries. CONSTITUTION:When a discharge valve 7 is fully closed and a pump 2B is activated, remaining air in a siphon pipe 3 is compressed by cut-off pressure of pump. Thus, the remaining air is purged to the atmosphere through an exhaust branch 8 mounted on the top 3c of the pipe 3 so that the siphon pipe 3 is filled up with water by the pump. Since thereafter the discharge valve 7 is fully opened to carry out forced feed by pump the remining air in the siphon pipe can be ejected for a short time without any disadvantageous increase of pump capacity and output of a drive.

Description

DETAILED DESCRIPTION OF THE INVENTION The present invention relates to a pump pressure feeding device having siphon pipes disposed at positions higher than the water level on the suction side and the discharge side.

As shown in FIG. 1, in a conventional pumping device of this kind, for example, one using a horizontal pump, the suction port 3a and the discharge port 3b of the siphon pipe 3 are at the suction side water level 4 and the bottom level 5 of the discharge water tank 6, respectively. At the lower level, the top portions 3C are located at positions 4.5 υ higher than both water levels. A horizontal pump 2 driven by a motor 12 is installed in the top portion 3C.
A person and a discharge valve 7 are provided, and a vacuum pump 1 is connected. In the pumping device having this structure, the two pumps are started after the vacuum pump 1 removes the air in the vacuum pump 3 and fills the siphon pipe 3 with water.

On the other hand, in a pump pressure feeding device in which an axle pump 2B is provided in the suction port 3a of the siphon pipe 3 as shown in FIG.
The discharge head H2 of the axle pump 2B is used to overflow the top 3c of the siphon pipe 30. Said axle pump 2
The pump characteristics of B are shown in FIG.

That is, since the overflow flow rate Q is controlled by the discharge head H8, it is small, and the flow velocity in the siphon pipe 3 is also slow, so that the effect of removing residual air is reduced. Therefore, siphon formation is delayed, and there are disadvantages such as increased loss in the siphon pipe due to the influence of residual air when the pump is started, vibration of the siphon pipe, and instability of pump operation. ' Therefore, in order to speed up sign-on formation, a method of increasing the pump discharge amount (Q, -H, curve) shown in FIG. 3 may be adopted. In this case, there is a disadvantage that the capacity of the pump and the output of the driver are increased, and the pump head becomes LH3 after the siphon is formed in FIG. 3, so the power consumption becomes P. Since this P is larger than Pl, the running cost may become high.

In view of the above, the present invention aims to quickly remove the residual air in the siphon pipe when the pump is started, without increasing the pump capacity and drive machine, and without using auxiliary equipment such as a vacuum pump. A discharge valve is provided at the siphon pipe discharge section located below the lowest water level on the side, and an exhaust branch is provided at the top of the siphon pipe.

An embodiment of the present invention will be described below with reference to the drawings.

In FIG. 4, reference numeral 2B denotes an axle pump installed in the suction port 3a of the siphon pipe 3 located below the suction water level 4, and this axle pump 2B is driven by a drive machine 12. 6 is a discharge water tank; 7 is a discharge valve provided in the discharge port 3b of the siphon pipe 3 which is located below the lowest ice level 5 of the discharge water tank 6 and is always submerged; 8 is a siphon pipe 30 is attached to the top part 3C with nine exhaust branches, and this exhaust branch 8 is provided with a safety check valve 9 and a shutoff valve 10. These valves9. .

Reference numeral 10 is provided to prevent negative pressure inside the siphon pipe 3 after the siphon is formed and to prevent air from being taken in from the exhaust branch 8.

This embodiment does not have the above configuration, but when the discharge valve 7 is fully closed and the pump 2B is started, the pump cut-off pressure (Hl)
As a result, the residual air within the pipe 3 is compressed.

Therefore, the residual air is discharged into the atmosphere by the exhaust branch 8 attached to the top 3C of the vibrator 30, so that the inside of the siphon pipe 3 is filled with water (by pumping water). After this filling, the discharge valve 7 is fully opened and the pump is operated under pressure.

As mentioned above, this embodiment takes advantage of the characteristic that the pump discharge pressure increases when the pump is closed, and eliminates the air in the siphon pipe, so it is only necessary to satisfy the condition Hl>Hl, and the pump discharge pressure increases. Since it is not related to the discharge amount, it is possible to eliminate the disadvantage of increasing the pump capacity and drive output.

As explained above, according to the present invention, the residual air in the siphon pipe can be eliminated in a short time without increasing the pump capacity and drive output and without using auxiliary equipment such as a vacuum pump. It is possible to easily form a self-supporting siphon even at a pressure pump station, and the reliability of pump alignment can be improved.

Furthermore, according to the present invention, the power consumption P1 after forming the siphon is smaller than the power consumption P1 of the conventional example (see FIG. 3), so running costs can be reduced.

[Brief explanation of the drawing]

Fig. 1 is a sectional view of a siphon-type pumping device equipped with a conventional horizontal pump, and Fig. 2 is a sectional view of a siphon-type pumping device equipped with a conventional chamber-shaft pump.
This figure is a pump characteristic diagram of the pump pressure feeding device of FIG. 2, and FIG. 4 is a sectional view showing an embodiment of the siphon type pump pressure feeding device of the present invention. 3...Siphon tube, 3b...Discharge part, 3C
...Top, 7...Discharge valve, 8...Exhaust branch.

Claims (1)

[Claims] In a pump pressure feeding device having a size 7-on pipe disposed at a position higher than the water level on each of the suction side and the discharge side, a discharge valve is provided at the size 7-on pipe discharge part located below the lowest water level on the discharge side, and A pump pressure feeding device characterized by having an exhaust branch attached to the top of the on-pipe.