JPS6235913Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to an air extraction device for a pump that does not have self-priming capability.

As is well known, in a pump that does not have self-priming capability, it is not possible to pump the transport liquid unless it is placed in the transport liquid or pushed into a state where the transport liquid reaches the pump's suction port. Conventionally, in such pumps, a vacuum pump or an ejector has been used to suck the liquid to be transported to the suction port.

However, when a vacuum pump is used, not only does the cost increase accordingly, but also failures due to abrasion of moving parts have been observed, and maintenance and inspection thereof have been troublesome.

In addition, if the conventional ejector-type air bleed system requires an explosion-protected area (for example, the pump room of an oil transport ship), safety regulations require explosion-proofing using electrical control parts such as pressure switches and solenoid valves. structure is required, which increases costs accordingly,
In addition, it was considered to be particularly unsuitable for installation in places where space is limited, such as on ships. Furthermore, if non-explosion-proof electrical control components are used, these components must be installed in a non-explosion-proof area separate from the pump body, which may complicate the installation work. This was inevitable due to the rising cost of equipment.

SUMMARY OF THE INVENTION The present invention has been made to eliminate the above-mentioned disadvantages, and the object of the present invention is to provide a pump bleed system which is capable of functioning without the use of electrical control members as described above and which facilitates installation. Another object of the present invention is to provide a pump bleed device that can reduce initial costs and running costs.

Next, an embodiment of the present invention that can achieve the above object will be described in detail with reference to the attached flowchart.

1 is a driving air supply valve, 2 is a hydraulically operated valve, 3 is an ejector, 4 is a pneumatically operated valve, 5 is a strainer, 6
7 is a pump and 7 is a liquid tank.

A discharge pipe 1a of the driving air supply valve 1 is connected to a hydraulically operated valve 2, and an ejector 3 having an exhaust pipe 3a via its discharge pipe 2a, and an intake pipe 3b of the ejector 3 is connected to a pneumatically operated valve 4 and a strainer 5. and is connected to the bleed pipe 6a of the pump 6. The discharge pipe 2a of the hydraulically operated valve 2 is connected to the pilot valve 4a of the pneumatically operated valve via a branch pipe 8, and the branch pipe 9 is connected to the discharge pipe 6b of the pump 6. Its end is connected to the pilot valve 2b of the hydraulically operated valve 2. Note that reference numeral 10 indicates a liquid suction pipe connecting the pump 6 and the liquid tank 7.

In the above configuration, pressurized air (usually 4 to 7 Kgf/cm ² G
When the valve 1 is opened, the pressurized air flows into the ejector 3 via the hydraulically operated valve 2, and the pressurized air from the branch pipe 8 closes the pneumatically operated valve 4.
The pilot valve 4a is opened. Pneumatically operated valve 4
The intake pipe 3b of the ejector 3 and the pump 6 are opened.
The air bleed pipe 6a is communicated via the strainer 5,
The air existing in the pump 6 and the liquid suction pipe 10 is bled through the air bleed pipe 6a and exhausted from the exhaust pipe 3a.

Pump 6 at the same time as the start of air extraction or after a desired time has elapsed.
Start. Then, the discharge pressure of the pump and the hydraulic pressure to the branch pipe 9 increase, and when this reaches the set pressure of the pilot valve 2b of the hydraulically operated valve 2, the hydraulically operated valve 2 is closed, and at the same time, the pneumatically operated valve 4 is also closed. Air extraction by the ejector 3 is completed.

When the pump 6 takes in air and its discharge pressure falls below the set pressure of the pilot valve 2b, the hydraulically operated valve 2 is opened again to resume air extraction.

Since the present invention is constructed as described above, it can function without the use of electrical control members as in the conventional type, and the installation work is easy. Therefore, the initial cost and running cost are lower than that of the conventional type. This has the effect of reducing the

[Brief explanation of the drawing]

The drawing is a flowchart showing one embodiment of the device of the present invention. 1... Drive air supply valve, 2... Water pressure operated valve, 2
b...Pilot valve, 3...Ejector, 3b...
...Intake pipe, 4...Pneumatically operated valve, 4a...Pilot valve, 6...Pump, 6a...Bleed pipe, 6b...
Discharge pipe, 8, 9...branch pipe.

Claims (1)

[Claims for Utility Model Registration] A hydraulically operated valve having a pilot valve connected to a discharge pipe of a drive air supply valve, an ejector connected to the discharge pipe of the hydraulically operated valve, and an ejector connected to the intake pipe of the ejector. a pneumatically operated valve having a pilot valve, and a pump connected to the pneumatically operated valve via a bleed pipe, the pilot valve of the hydraulically operated valve being connected to a branch pipe connected to a discharge pipe of the pump. An air extraction device for a pump characterized in that the pilot valve of the pneumatically operated valve is connected to a branch pipe connected to a discharge pipe of the hydraulically operated valve.