JP3102545B2 - Pump device for weighing machine - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention comprises a pump in a casing and a gas-liquid separator provided on the outlet side of the pump.
The present invention relates to a pump device for a weighing machine that separates a liquid containing gas separated by a gas-liquid separator into a gas and a liquid in a float chamber, and returns the liquid to an inlet side of the pump when a float valve provided in the float chamber is opened.

[0002]

2. Description of the Related Art Various pump devices for a weighing machine are known, and the applicant of the present invention has also disclosed Japanese Patent Publication No. 5-50593.
JP, JP-B-4-15399, JP-A-4-60
No. 97, Japanese Unexamined Patent Publication No. 5-19397, and the like.

[0003] Further, there is known a fueling station in which a plurality of weighing machines are connected from one underground tank via one fueling pipe. In such a case, when one weighing machine is not used and another weighing machine is used, a water hammer is generated in the refueling pipe when refueling is stopped, and the check valve provided on the inlet side of the pump device is pushed and opened. As a result, the oil flows in, and the flow-in oil pushes up the float valve without flowing back due to the check valve, and flows into the float chamber. As a result, the float chamber is filled with oil, and the oil is ejected to the outside from the air vent. To solve such inconvenience,
Japanese Utility Model Publication No. 61-15265 discloses a technique of closing an air vent with a shielding plate.
Japanese Patent Publication No. -6097 discloses a technique in which a check valve is not provided and oil flows backward to an underground tank.

[0004] However, the oil that has flowed in is not discharged even if it is blocked by the shielding plate, and is stored in the casing. This is inconvenient. Since all the oil inside the spills out, the treatment is troublesome.

A technique for providing a float chamber is also disclosed in, for example, Japanese Patent Publication No. 51-27483.

[0006]

SUMMARY OF THE INVENTION Accordingly, an object of the present invention is to provide a strainer provided at an inlet of a casing without filling the float chamber with oil even if oil flows into the float chamber by a water hammer. An object of the present invention is to provide a pump device for a weighing machine which does not require the entire amount of oil in a casing to flow out during cleaning.

[0007]

According to the present invention, a pump is provided in a casing and a gas-liquid separator provided at an outlet side of the pump, and a liquid containing a gas separated by the gas-liquid separator is floated. In a pump device for a weighing machine in which gas is separated into liquid and liquid in the chamber and the liquid is returned to the inlet side of the pump when the float valve provided in the float chamber opens, the inlet of the casing communicates with the inside of the cylindrical strainer. The outer chamber of the strainer communicates with the chamber on the inlet side of the pump via a check valve, and the outlet passage of the float chamber communicates with the outer chamber of the strainer.

[0008]

[Explanation of operation and effect] Therefore, with the operation of the pump,
Oil in the underground tank is sucked up from the oil supply pipe and flows into the inlet of the casing. Then, the dust enters the inside of the strainer, the dust is removed by the strainer, flows into the outside chamber, and is sucked into the pump from the chamber on the inlet side of the pump via the check valve.

On the other hand, the oil pressurized by the pump is separated from the oil containing gas in the gas-liquid separation chamber, the oil containing no gas is supplied, and the oil containing gas flows into the float chamber. Gas and liquid are separated in the float chamber, and when a certain amount of separated oil is stored, the float valve opens and flows from the outlet flow path to the chamber outside the strainer.

In the present invention, since the outlet flow path from the float chamber is connected to the upstream side of the check valve, a pressure wave is generated at the inlet of the casing by the water hammer, and the float valve is pushed up to allow oil to flow therethrough. However, when a certain amount of oil accumulates in the float chamber, the float valve opens and flows out through the strainer, so that the float chamber is not filled with oil.

When cleaning the strainer, the flow path communicating with the chamber outside the strainer is closed by the check valve and the float valve, so that the outflow of oil can be minimized.

[0012]

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

In FIG. 1, a pump device for a weighing machine according to the present invention includes a box-shaped casing C, and an inlet I and an outlet O are formed in the casing C. The inflow port I communicates with the inner side 3 of the cylindrical strainer 2, and an outer chamber 4 is formed outside the strainer 2, and the outer chamber 4 is connected via a check valve 5 to a chamber on the inlet side of the pump 6. It communicates with 7. The chamber 8 on the outlet side of the pump 6 communicates with a gas-liquid separation device indicated generally by reference numeral 9.

In the illustrated example, the gas-liquid separation device 9 is described in Japanese Patent Application Laid-Open No. Hei 5-193699, which is assigned to the present applicant, and includes a spiral chamber 10, a cylindrical member 11, and a detent member 12. And a gas-liquid mixed flow passage 13 provided on the opposite side of the rotation preventing member 12 with respect to the cylindrical member 11. As described in the above-mentioned publication, the gas-liquid separation device 9 causes the swirling flow generated in the swirl chamber 10 to flow toward the rotation-stopping member 12 while swirling the cylindrical member 11. It gathers at the center of the spiral chamber 10 and the cylindrical member 11 and flows out from the gas-liquid mixed flow passage 13.

A strainer 14 is provided radially outward of the cylindrical member 11. The strainer 14 is positioned by a lid 15 attached to the outside of the casing C via a spring 16 and the detent member 12.

The upper part of the chamber 17 on the radially outer side of the strainer 14 communicates with the outlet O via a control valve 18, and the lower part of the chamber 17 on the inlet side of the pump 6 via a bypass valve 19. Is in communication with

The gas-liquid mixed flow passage 13 communicates with a float chamber 21 through a passage 20.
Is provided with a float valve 22. The float valve 22 is opened when oil accumulates in the float chamber 21 up to the level L. Therefore, the air vent V is provided above the level L. The outlet passage 23 of the float chamber 21 communicates with the outer chamber 4 outside the strainer 2.

In the illustrated example, the check valve 5 is of a gravity type.
An opening 24 is formed in the opening 24, and the opening 24 is always closed by a cover 25.

Next, the operation will be described mainly with reference to FIG.

Oil from an underground tank (not shown) flows into an inlet port I through an oil supply pipe (not shown), and dust and the like are removed by a strainer 2. It flows into the chamber 7 and is sucked by the pump 6. The oil pressurized by the pump 6 flows from the outlet side chamber 8 into the swirl chamber 10 of the gas-liquid separation device 9 to generate a swirling flow, and the relatively light gas-liquid mixed flow passes through the gas-liquid mixed flow passage 13 It flows into the float chamber 21 via 20.

The oil containing no gas passes through the strainer 14, pushes the cotton roll valve 18 open, flows to the outlet O, and is supplied from an oil supply nozzle (not shown).

When the pump 6 is operating but not supplied, the oil from the pump 6 returns to the inlet side chamber 7 through the bypass valve 19 and circulates.

The gas-liquid mixture flowing into the float chamber 21 is separated into gas and liquid, and the gas, that is, the vapor is discharged from the air vent V to the atmosphere. When a certain amount of oil is accumulated in the float chamber 21, the float valve 22 is opened, and the oil in the float chamber is returned from the passage 23 through the strainer 2 to the underground tank through the inlet I. If the pump 6 is operating, it is sucked into the pump 6.

As described above, in the present invention, when the float valve 22 is opened, the oil in the float chamber 21 can flow out to the underground tank through the strainer 2, so that the oil is floated into the float chamber 21 by the water hammer when the weighing machine is not used. The float chamber 21 will not be filled with oil even when flowing from the valve 22.

When the strainer 2 is replaced, the outer chamber 4 outside the strainer 2 is closed by the check valve 5 and the float valve 22, so that the amount of outflowing oil is small and the processing is easy.

[0026]

As described above, according to the present invention, the following excellent effects can be obtained. (1) Since the passage from the float chamber communicates with the inflow port on the upstream side of the check valve, when the float valve is opened, the oil in the float chamber can reliably flow out to the underground tank side, and the float chamber is filled with oil. It is full and does not blow out from the air vent. (2) Since the outer chamber of the strainer is closed by the check valve and the float valve, when cleaning or replacing the strainer, the amount of spilled oil is minimized and processing is easy.

[Brief description of the drawings]

FIG. 1 is a sectional view showing an embodiment of the present invention.

FIG. 2 is a schematic diagram showing a flow of a pump device for a weighing machine embodying the present invention.

[Explanation of symbols]

 I ... Inlet O ... Outlet C ... Casing V ... Air vent 2 ... Strainer 3 ... Inside strainer 4 ... Outside chamber 5 ... Check valve 6 ... Pump 7: Chamber on the inlet side 8: Chamber on the outlet side 9 ... Gas-liquid separator 14 ... Strainer 17 ... Chamber 18 ... Control valve 19 ... Bypass valve 20 ...・ Passage 21 ・ ・ ・ Float chamber 22 ・ ・ ・ Float valve 23 ・ ・ ・ Path

Continuation of the front page (56) References JP-A-5-193697 (JP, A) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04B 53/20 B67D 5/06

Claims (1)

(57) [Claims] 1. A pump having a pump and a gas-liquid separator provided on an outlet side of the pump in a casing, wherein a liquid containing a gas separated by the gas-liquid separator is separated into a gas and a liquid in a float chamber. In a pump device for a measuring device in which liquid is returned to the inlet side of a pump when a float valve provided in a float chamber is opened, an inlet of a casing communicates with an inside of a cylindrical strainer, and a chamber outside the strainer is A pump device for a weighing machine, wherein the pump device communicates with a chamber on the inlet side of a pump via a check valve, and an outlet passage of the float chamber communicates with a chamber outside the strainer.