JP2001073979A - Self-priming pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To suppress seizure of a sliding part caused at the time of an operation by priming, deterioration of a material, and generation of frictional noise and the like by forming a groove from a center to an outer periphery at an upper position from a center of a pump chamber on a pump chamber side wall so as to shut out flow of circulating water in water passage parts of an outer periphery and a back surface of the pump chamber and an impeller. SOLUTION: A groove 17 is formed on a pump chamber 7 side wall of a casing 3 from a center to an outer periphery at an upper position from a center of the chamber 7 so as to shut out flow of circulating water in water passage parts of an outer periphery and a back surface of the pump chamber 7 and an impeller. Even at the time of an operation by priming into a pump, flow of the circulating water in an outer peripheral part of the impeller 6 is changed, a part of circulating water is supplied to a sliding part of a rotation side mechanical seal and a fixing side mechanical seal by passing the groove 17. It is thus possible to suppress seizure of the sliding part, deterioration of a material, and generation of frictional noise and the like.

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a self-priming pump used in a hot water supply / heating apparatus or the like.

[0002]

2. Description of the Related Art Generally, a self-priming pump has a casing for accommodating an impeller and a casing cover for priming for filling the impeller accommodating portion of the casing with water.

[0003] In particular, as a pump of a type in which a casing and a casing cover are integrated, there is a pump configured as shown in FIG.

FIG. 6 is a sectional view of a conventional self-priming pump, and FIG.
Is a plan view of the self-priming pump in a state where the impeller is assembled into a casing, which will be described with reference to FIGS. 6 and 7. FIG.

As shown in FIG. 6, a motor 1 is provided with a bracket 2 made of a rust-prevented iron plate. The bracket 2 is made of a resin molded product for corrosion resistance, rust resistance and weight reduction. A casing 3 having an open end opposite to the motor 1 is attached.

A shaft 4 connected to the motor 1 and made by cutting a steel round material is inserted into the casing 3, and a screw is formed at the tip of the shaft 4.
Further, the casing 3 forms a pump chamber 7 and a water supply chamber 8 that house an open impeller 6 having a plurality of blades 5. The impeller 6 is made of a resin molded product in order to reduce corrosion resistance, rust resistance, and weight. Then, a threaded product of a brass round bar cutting material or a brass knurl material is inserted, and the threaded product is screwed to a screw of the shaft 4 to couple the impeller 6 to the shaft 4. Further, a rotary mechanical seal 9 made of carbon, spring and rubber packing is provided on the outer peripheral portion of the cylindrical rotary portion of the impeller 6, and this rotary mechanical seal 9 is attached to the pump chamber 7 of the casing 3. The shaft 4 is slid on a fixed mechanical seal 10 made of ceramic and rubber packing attached to a penetrating portion of the shaft 4 to prevent water leakage.

On the opening side of the casing 3, the opening side of the casing cover 13 is connected via a partition plate 11 having a water inlet at a predetermined position and a packing 12. The partition plate 11 is made of a pressed SUS plate in order to impart corrosion resistance and rust resistance and to reduce the weight. The casing cover 13 forms a priming tank 14 inside, and the suction port 15 It has an outlet 16 and is made of a resin molded product to reduce corrosion resistance, rust resistance, and weight.

Next, the operation of the self-priming pump configured as described above will be described.

First, priming water is injected into the casing cover 13 in advance. The water injected into the casing cover 13 fills the priming tank 14 and the pump chamber 7 and the water supply chamber 8 in the casing 3.

At the time of starting, the rotation of the motor 1 is transmitted to the impeller 6 by the shaft 4 and the pump chamber 7 in the casing 3 is rotated.
The impeller 6 housed in the container rotates. Then, the water in the pump chamber 7 is stirred by the impeller 6, and air is mixed into the water. As shown by the arrow a in FIG.
Only the air that is pushed out of the pump chamber 7 and the water supply chamber 8 along the outer periphery of the impeller 6 and flows into the priming tank 14 of the casing cover 13, and only the air that is pushed out together with the water is discharged from the discharge port 1.
Outflow from 6 If this state continues, the air pressure in the pump chamber 7 in the casing 3 gradually decreases, and the pressure difference between the pump chamber 7 and the outside causes the suction port 15
When water enters and a full-scale water delivery state is entered, the priming tank 14 of the casing cover 13 is filled with water, and overflowing water flows out of the discharge port 16 to the outside.

At this time, the rotation of the impeller 6 gives a centrifugal force to the water, and acts to increase the pressure of the water flow introduced into the impeller 6. In addition, the pump chamber 7 and the water supply chamber 8 have a function of discharging the water flow flowing out of the impeller 6 to the priming tank 14 of the casing cover 13. Also, the casing cover 1
3, water is introduced from the suction port 15 to the pump chamber 7 of the casing 3 and discharged from the water supply chamber 8 of the casing 3 to the priming tank 14 of the casing cover 13 and the discharge port 1.
6 to discharge to the outside. Further, the partition plate 11 having the water inlet performs a pressure increasing action on the water flow of the impeller 6.

[0012]

However, in the self-priming pump having the above-described structure, it takes several tens of seconds from the start to a full-scale water delivery state. During this time, the pump chamber 7 contains water and air. As shown in FIG. 7, this mixed water circulates only at the outer peripheral portion of the impeller 6 due to the action of centrifugal force, and water does not flow to the back surface of the impeller 6, so that the mixed water is fixed to the rotating side mechanical seal 9. The sliding portion of the side mechanical seal 10 is in an idle operation state (a state in which no fluid film is formed).

Since the mechanical seal seals while rotating at a high speed, a fluid film is formed on the sliding portion of the rotating mechanical seal 9 and the fixed mechanical seal 10 to improve the lubricating state, and the long-lasting state is obtained. Although it is configured to maintain the sealing function, as described above, when the sliding part is in an idle running state, seizure of the sliding part, water leakage due to deterioration of the material, frictional noise (mechanical noise and This causes the quality of the self-priming pump to deteriorate, such as the occurrence of abnormal noise due to the so-called sound).

An object of the present invention is to solve the above problems and to provide a self-priming pump having excellent mechanical seal quality.

[0015]

In order to solve the above-mentioned problems, a self-priming pump according to the present invention interrupts the flow of circulating water in a pump chamber of a casing and a water passage portion on the outer periphery and the back surface of an impeller. A groove is formed on the side wall of the pump chamber of the casing at a position above the center of the pump chamber of the casing and from the center to the outer periphery so as to guide the circulating water of the outer peripheral portion of the impeller to the sliding portion of the mechanical seal. It was done.

According to the present invention, a part of the circulating water on the outer peripheral portion of the impeller is supplied to the sliding portion of the mechanical seal even during the operation with the priming water into the pump due to the groove of the pump chamber of the casing. In addition, the occurrence of seizure of the sliding portion, deterioration of the material, and generation of frictional noise can be suppressed.

[0017]

The invention according to claim 1 of the present invention comprises a motor, an impeller fixed to a rotating shaft of the motor, and a casing for accommodating the impeller and forming a pump chamber. A self-priming pump comprising a casing cover coupled to the casing via a partition plate having a water inlet and packing, and forming a priming tank therein, wherein the pump chamber of the casing and the impeller A groove is formed in the side wall of the pump chamber of the casing at a position above the center of the pump chamber of the casing and from the center to the outer periphery so as to block the flow of circulating water in the water passage portion on the outer periphery and the back surface portion. Self-priming pump that can supply a part of the circulating water on the outer periphery of the impeller to the sliding part of the mechanical seal even during operation with priming water into the pump. Degradation, has an effect of suppressing the generation of frictional noise, and the like.

According to a second aspect of the present invention, in the self-priming pump according to the first aspect, the groove is formed at an arbitrary position on a side wall of the pump chamber of the casing, and has a width, a depth, and a length. Are set arbitrarily, and the end on the center side is positioned directly above the sliding portion of the rotating mechanical seal and the fixed mechanical seal, and has the same effect as the first aspect.

Hereinafter, embodiments of the present invention will be described with reference to the drawings.

(Embodiment 1) FIG. 1 is a sectional view of a self-priming pump according to Embodiment 1 of the present invention, FIG. 2 is a plan view of a casing of the self-priming pump, and FIG. It is AA sectional drawing in. The same components as those of the conventional self-priming pump described above are denoted by the same reference numerals, and the description of the configuration and operation is omitted.

The feature of the self-priming pump of the first embodiment resides in the casing, that is, as shown in FIGS.
A groove 17 is formed in a side wall of the pump chamber 7 so as to block the flow of circulating water in the water passage portion on the outer peripheral portion and the back surface portion of the pump chamber 7 and the impeller 6 of the casing 3. That is, the groove 17 is located above the center of the pump chamber 7 of the casing 3 and is formed so as to extend from the center to the outer periphery.

As described above, the groove 17 on the side wall of the pump chamber 7 in the self-priming pump according to the first embodiment can maintain the impeller 6 as shown by the arrow b in FIG. The flow of the circulating water in the outer peripheral portion is changed, and a part of the circulating water is supplied to the sliding portion of the rotating mechanical seal 9 and the fixed mechanical seal 10 through the groove 17,
Seizure of the sliding portion, deterioration of the material, generation of friction noise, and the like can be suppressed.

(Embodiment 2) FIG. 4 is a plan view of a casing of a self-priming pump according to Embodiment 2 of the present invention, and FIG. 5 is a sectional view taken along line AA in FIG.

The feature of the second embodiment is that, in the pump chamber 7 of the casing 3 of the first embodiment, as shown in FIG. A groove 17a formed so as to block the flow of circulating water in the portion is formed at an arbitrary position on the side wall of the pump chamber 7, and its width, depth, and length are arbitrarily set, and toward the center. The extended end is located directly above the sliding portion of the rotating mechanical seal 9 and the fixed mechanical seal 10.

According to this configuration, the groove 17a in the side wall of the pump chamber 7 allows the flow of the circulating water on the outer peripheral portion of the impeller 6 even during the operation with the priming water into the pump, as shown by the arrow c in FIG. And a part of the circulating water is supplied to the sliding portion of the rotating side mechanical seal 9 and the stationary side mechanical seal 10 through the groove 17a. Can be suppressed.

[0026]

As is apparent from the above description, the self-priming pump of the present invention has a casing for accommodating an impeller so that the side wall of the pump chamber blocks the flow of circulating water around the outer periphery of the impeller. Since the groove is formed, the flow of circulating water on the outer periphery of the impeller is changed even during operation with priming water into the pump, and the sliding of the rotating mechanical seal and the fixed mechanical seal is performed along the groove. Part can be supplied with part of the circulating water, thus seizing the sliding parts,
The quality of the self-priming pump can be improved by suppressing the deterioration of the material and the generation of friction noise, etc., and the effect is large.

[Brief description of the drawings]

FIG. 1 is a sectional view of a self-priming pump according to a first embodiment of the present invention.

FIG. 2 is a plan view of a casing in the self-priming pump.

FIG. 3 is a sectional view taken along line AA in FIG. 2;

FIG. 4 is a plan view of a casing in a self-priming pump according to Embodiment 2 of the present invention.

FIG. 5 is a sectional view taken along line AA in FIG.

FIG. 6 is a sectional view of a conventional self-priming pump.

FIG. 7 is a plan view of the self-priming pump in a state where the impeller is assembled into a casing.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Motor 2 Bracket 3 Casing 4 Shaft 5 Blade 6 Impeller 7 Pump room 8 Water supply chamber 9 Rotary side mechanical seal 10 Fixed side mechanical seal 11 Partition plate 12 Packing 13 Casing cover 14 Priming tank 15 Suction port 16 Discharge port 17 Groove 17a groove

Claims (2)

[Claims] 1. A casing comprising a motor, an impeller fixed to a rotating shaft of the motor, and a casing for accommodating the impeller and forming a pump chamber, wherein the casing is provided via a partition plate having a water passage and packing. And a self-priming pump including a casing cover that forms a priming tank inside, and controls a flow of circulating water in a pump chamber of the casing and a water passage portion on an outer periphery and a back surface portion of the impeller. To block, on the side wall of the pump chamber of the casing, at a position above the center of the pump chamber of the casing,
A self-priming pump characterized by forming a groove extending from the center to the outer periphery. 2. The groove is formed at an arbitrary position on the side wall of the pump chamber of the casing, and the width, the depth and the length are arbitrarily set.
2. The self-priming pump according to claim 1, wherein an end on the center side is located directly above a sliding portion between the rotating mechanical seal and the fixed mechanical seal.