JP2001140770A - Gear pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide a small high pressure liquid transmitting pump having a compact size, a simple structure, excellent transmitting performance, and excellent maintainability, allowing excellent layout in a factory. SOLUTION: The structure of this gear pump 1 has a feature that it is composed of a pair of gears 3 meshing with each other; two rotary gears 2A, 2B sequentially operable by a common driving shaft 5 are mounted side by side in a single pump casing 4 in parallel; the rotary gear 2A on the suction port S side of the pump casing 4 is structured as an initial stage pressurizing force feeding part, the rotary gear 2B on the discharge port D side of the pump casing 4 is structured as a final stage pressurizing force feeding part; fluid passages 11.12.13 reaching the suction side of the rotary gear 2B from the delivery side of the rotary gear 2A are provided, liquid L is pressurized in two stages by the initial and final pressurizing force feeding parts, to deliver the liquid having a high pressure of 30 kgf/cm2.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a gear pump used for pumping liquid, and more particularly to a gear pump used for pumping liquid at high pressure in a production line in a factory.

[0002]

2. Description of the Related Art A gear pump for liquid pressure feeding has a structure in which a rotary gear composed of a pair of gears meshing with each other is housed in a pump casing, and is usually used as a pump for medium-to-low pressure feeding such as 5 kgf per square centimeter or less. Widely used in On the other hand, when the liquid is pumped to a high pressure such as "15-60 kgf per square centimeter",
2. Description of the Related Art A plunger pump that reciprocates a plunger in a cylinder to perform high-pressure pumping is widely used.

[0003]

The above-mentioned conventional gear pump has the advantage of being small and compact and having an excellent liquid delivery amount, but has the drawback that high-pressure pumping cannot be performed. One plunger pump is suitable for high-pressure pumping. Since the liquid pressure feeding system is caused by the reciprocating operation of the plunger, a pulsation is generated. Therefore, it is necessary to prevent the pulsation and to improve the amount of the pulsation by using a multi-unit configuration such as four to six units. Since the crank mechanism is indispensable, the structure is complicated, the size is large, the cost is high, and the maintenance is complicated. In addition, the space occupied by the installation due to the large size increases the layout in the factory. There are difficulties such as chipping.

An object of the present invention is to provide a gear pump capable of high-pressure pumping, which solves the above-mentioned disadvantages of the prior art, is small, lightweight, and compact and has an excellent delivery amount.

[0005]

A gear pump according to the present invention for solving the above technical problem is a gear pump for liquid pressure feeding in which a rotary gear comprising a pair of gears meshing with each other is housed in a pump casing. Are mounted in a single pump casing by being connected in parallel so as to be interlocked by a single drive shaft, and the rotary gear on the liquid suction port side of the pump casing is a first-stage pressurized pumping unit, and a liquid discharge port of the pump casing. The rotary gear on the side is configured as a final-stage pressurizing and pumping unit, and further a pumping liquid flow path from the discharge side of the initial-stage pressurizing and pumping unit to the suction side of the final-stage pressurizing and pumping unit is provided. Has become.

That is, in the gear pump of the present invention, the liquid is transferred by 180 ° by rotation of the gear in which the liquid is put in the space surrounded by the inner circumference of the pump casing and the inter-dental space of the gear provided in the pump casing. In a gear pump composed of a pump mechanism that sequentially sends out liquids, each rotary gear of the parallel connection is driven by setting the liquid pressure difference between the liquid suction side and the liquid discharge side to `` about the medium pressure capable of liquid pressure feeding '',
It is characterized in that the pressurizing force of each of the serially mounted rotary gears is accumulated so that high-pressure liquid such as 30 to 60 kgf per square centimeter can be sequentially sent out from the final stage pressurizing and feeding unit.

[0007] The rotary gear is connected in parallel in two or three, and a separate flow path member for securing a liquid flow path of the pumping liquid between the rotary gears in the parallel connection is provided by a rotary gear. A mode of internally setting between the relative side portions is adopted.

[0008]

In the gear pump of the present invention having the above-described structure, the rotary gears connected in parallel function as a plurality of stages of pressurizing and pressure-feeding units, so that a high-pressure liquid can be sent in a forward direction by a small and compact single gear pump having an excellent pump delivery amount. .

[0009]

DETAILED DESCRIPTION OF THE PREFERRED EMBODIMENTS First, a gear pump according to a first embodiment of the present invention will be described in detail with reference to FIGS. That is,
In the gear pump 1 of this embodiment, a rotary gear 2 composed of a pair of gears 3 meshing with each other is housed and mounted in a pump casing 4, and a liquid L sucked from a suction port S of the pump casing 4 is discharged and fed from a discharge port D. In the gear pump, two rotary gears 2A and 2B of the same size and the same shape that are interlocked by a common drive shaft 5 are connected in parallel to a single pump casing 4 (hereinafter simply referred to as casing 4).

More specifically, the casing 4 is made up of a casing main body 7 in the form of a cylinder having both ends opened, and a case body closed on both sides by side wall lids 8A and 8B which are fixed by bolts to both side openings of the casing main part 7. The two rotary gears 2A and 2B mounted on the drive shaft 5 and the interlocking shaft 6 are stored and set in the hollow portion of the case body. The drive shaft 5 and the interlocking shaft 6 are supported by bearings 9 provided on the side wall lids 8A and 8B. One end of the drive shaft 5 projects from the casing 4, and the drive shaft 5 is rotated as an input shaft. The two rotary gears 2 </ b> A and 2 </ b> B work together in the casing 4 to operate as a liquid pump gear pump.

The casing 4 has a suction port S on the rotary gear 2A side and a discharge port D on the rotary gear 2B side (see FIG. 2). The flow path 11 and the discharge port D 180
° It has the liquid flow path 12 of the concave groove located on the opposite side.

Further, between the opposed sides of the two rotary gears 2A and 2B arranged in parallel, a separate flow path member 10 is provided.
Are inserted and set, and the rotary gear 2A
The liquid flow path 11 and the liquid flow path 12 whose positions are opposite to each other by 180 ° with respect to 2B form a liquid flow path that passes through the intermediate flow path 13 provided in the flow path member 10.

That is, the flow path member 10 (see FIG. 3) is an upper piece 16 of a short and small circular ring having a shaft hole 18 of the drive shaft 5.
And a lower piece 17 of a short and short circular ring having a shaft hole 18 of the interlocking shaft 6, a U-shaped concave groove 15 is annularly provided on the outer periphery of both the upper and lower pieces 16 and 17. The two upper and lower pieces 16 and 17 are vertically joined and set at a flat joint 19 where the upper half of the groove wall of the concave groove 15 is cut, and the outer periphery is inserted along the inner periphery of the hollow portion of the casing main portion 7. Is set.

When the flow path member 10 is inserted and set in the gap between the opposing side surfaces of the two rotary gears 2A and 2B, an upper intermediate flow path 13A formed by the concave groove 15 on the upper half outer periphery of the upper piece 16, A lower intermediate flow path 13C formed by the concave groove 15 on the lower half outer periphery of the lower piece 17 and a central intermediate flow path 13B formed by the concave groove 15 of the upper and lower pieces 16 and 17 at the upper and lower joining points are formed.・ 13B ・ 13C
The liquid flow paths 11 and 12 located on the opposite side of the casing main part 7 through 180 ° communicate with each other through the through hole, and the liquid L pumped by the rotation of the rotary gear 2A passes through the flow paths 11 and 12.
The path 13 is fed by pressure to the suction side of the rotary gear 2B. The flow path member 10
In order to facilitate the suction of the liquid L into the intermediate flow paths 13A, 13B, and 13C, a "liquid suction opening 20 that is formed by partially cutting the side wall of the concave groove 15 and opening" is set in the first flow path.

The above gear pump 1 is mounted on a liquid pressure feed line, and a bypass pipe provided with a pressure regulating valve is provided between the liquid feed pipe connected to the suction port S and the liquid flow path 11 (or 12) although not shown. Piping is configured. Then, when the drive shaft 5 is driven to rotate as an input shaft, the rotary gear 2A on the suction port S side sends the liquid L to the flow path 11 in a primary pressurized state such as 15 kgf per square centimeter. Then, the liquid L in the primary pressurized state is supplied to the flow path 11 in the pressurized state.
.Rotary gear 2 on the discharge port D side via 12.13
The liquid is sucked into B and subjected to secondary pressurization, and is pressurized and sent to a liquid feed pipe connected to the discharge port D in a high-pressure pressurized state of 30 kgf / cm 2.

Thus, the rotary gear 2A functions as a first-stage pressurizing and pressure-feeding unit and the rotary gear 2B functions as a final-stage pressurizing and pressure-feeding unit. The high-pressure liquid is sent out sequentially. Note that the clearance between the rotary gears 2A and 2B of this embodiment and the inner periphery of the casing 4 is approximately 0.10 to 0.1.
The clearance between the outer circumference of the flow path member 10 and the inner circumference of the casing 4 is approximately 1.0 to 1.5 abrasion (one side).

Next, another embodiment of the gear pump 1 of the present invention will be described with reference to FIG. That is, in the case where the rotary gears 2 are arranged in a row in the casing 4, the rotary gear 2 shown in FIG. 4 is formed in a triple arrangement in which three rotary gears 2A, 2B, and 2C are arranged in a row.
The flow path member 10 is inserted between 2B and between 2B and 2C, and the rotary gear 2A on the suction port S side is a first-stage pressurizing and pressure-feeding unit, the intermediate rotary gear 2B is a middle-stage pressurizing and pressure-feeding unit, and a discharge port D. The rotary gear 2C on the side is a three-stage pressurizing system that functions as a final-stage pressurizing and feeding unit.

In the embodiment shown in FIG. 4, the liquid L is pressurized to about 20 kgf per square centimeter in the first-stage pressurizing and pumping section, and is increased and pressurized to about 40 kgf per square centimeter in the middle-stage pressurizing and pumping section. About 60 in part
It can be delivered at a high pressure of kgf per square centimeter.

The gear pump 1 according to the above-described embodiment has the above-described operation, and rotates a group of rotary gears connected in parallel in a single casing by a single drive shaft 5 so as to rotate.
High-pressure liquid can be delivered smoothly. And since it is a rotary pump system by a gear, it is small and compact compared with the conventional plunger pump, the structure is simple, and a high-quality high-pressure liquid free of liquid discharge pulsation can be delivered and supplied at a high delivery rate. Since the structure is simple, the installation space is small and sufficient, and the pump is easily maintained and can be effectively used as a high-capacity high-pressure pump in various fields.

The gear pump according to the present invention is not limited to the above-described embodiment.
In place of 0, the dayberry side of the rotary gear 2A and the suction side of the rotary gear 2B are made into a liquid flow path connected by a liquid feed pipe straddling the casing 4, or the rotary gears 2A and 2B, etc., connected to each other have the same pitch circle diameter. Gear 3 whose tooth profile becomes smaller gradually from 2A to 2B ・ 2C
And so on.

[0021]

As described above, the gear pump according to the present invention is a compact, compact, simple, inexpensive, high-pressure liquid pump with excellent delivery performance, and has good maintainability and factory layout. This has the effect of improving convenience in the field.

[Brief description of the drawings]

FIG. 1 shows a gear pump according to a first embodiment of the present invention, and (A)
Is a front sectional view, and (B) is a plan sectional view.

FIG. 2 is a sectional view of the gear pump according to the embodiment shown in FIG. 1;
1A is a cross-sectional view taken along the line DD in FIG. 1A, and FIG.
FIG. 1C is an EE cross-sectional view, and FIG. 1C is a FF cross-sectional view of FIG.

FIG. 3 shows a flow path member of the gear pump of FIG. 1 embodiment,
(A) is a side view thereof, and (B) is a GG sectional view of (A).

FIG. 4 is a front sectional view of a gear pump according to another embodiment of the present invention.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Gear pump 2A ・ 2B ・ 2C Rotary gear 3 Gear 4 Pump casing 5 Drive shaft 6 Interlocking shaft 7 Casing main part 8A ・ 8B Side wall cover 10 Flow path member 11 ・ 12 Liquid flow path 13 Intermediate flow path 15 Recessed groove 16 Upper piece 17 Lower piece S Inlet D Outlet L Liquid

Claims (3)

[Claims] 1. A gear pump for liquid pressure feeding in which a rotary gear composed of a pair of gears meshing with each other is housed in a pump casing. The rotary gear on the liquid suction port side of the pump casing is configured as a first stage pressurized pumping unit, and the rotary gear on the liquid discharge port side of the pump casing is configured as a final stage pressurized pumping unit. A gear pump having a structure in which a pumping liquid flow path is provided from a discharge side of the first-stage pressurizing and pumping section to a suction side of the final-stage pressurizing and pumping section. 2. The gear pump according to claim 1, wherein the rotary gears are arranged in three parallel arrangements, and an intermediate rotary gear of the three arrangements is formed as a middle-stage pressurizing and feeding section located in the middle of the liquid flow path for pumping. 3. A separate liquid flow path member having a ring-shaped groove formed around the outer periphery of a liquid-feeding liquid flow path is provided between the opposed side portions of the rotary gear pump of the parallel connection. Gear pump.