JP2003003999A - Axial pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To effectively convert a swirl flow generated by an impeller into delivery pressure to improve pump performance. SOLUTION: In this axial pump 1 provided with a cylindrical housing 27 stored with a stator 26, an inlet side casing 4 arranged in one side of a hollow part of the housing to form an inlet side of a flow passage for a fluid, an outlet side casing 3 arragned in the other side of the hollow part of the housing to form an outlet side for the flow passage for the fluid, and an impeller 22 attached rotatably to a fixed shaft 2 provided inside the stator and arranged in the flow passage formed by the inlet side casing 4 and the outlet side casing 3, wherein a support part 6 for supporting the fixed shaft 2 on the pump center line is in the outlet side casing 3, and wherein radial ribs for supporting the support part 6 are provided in an outlet side casing wall 11, each of the radial rib is a spirally curved rib 5 extended toward an outer circumferential direction of the outlet casing, and its inclination is moderated in accompaniment to approaching to an outer circumference.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to an axial flow pump for improving pump performance, and more particularly to an axial flow pump suitable for being incorporated and used in devices such as a water heater and a vehicle-mounted radiator device.

[0002]

2. Description of the Related Art A conventional axial flow pump 50 has an impeller 52 mounted on a metal bearing 51 and a rotor magnet 53 connected to the impeller 52, as shown in a vertical sectional view of a pump of FIG.
Is housed in the pump casing about a fixed shaft 54 arranged on the pump center line.

The pump casing of the axial flow pump 50 includes an inlet side casing 55 on the suction port 56 side and a discharge port 58.
The outlet side casing 57 on the downstream side having an O-ring 59 is fastened to form a flow path 60 inside the casing, and the water sucked from the suction port 56 by the rotation of the impeller 52 becomes a swirling flow 61. While passing through the flow path 60 while being accelerated, it flows into the discharge pipe 62 of the outlet side casing 57 and is discharged from the discharge port 58.

As shown in the front view of the outlet side casing 57 of FIG. 7 and the sectional view of FIG. 8 (cross section taken along the line A--O--B of FIG. 7), the inner surface wall 63 of the outlet side casing 57 on the rear face of the impeller 52 is shown. Is fitted to one end of the fixed shaft 54, and
A support portion 64 having a concave portion for supporting 4 in the center of the pump casing is provided in the central portion, and the support portion 64 is supported in the central portion of the outlet side casing 57 and fixed radially to the outer peripheral direction of the casing. A plurality of linear ribs 65 extending with a gradually lower inclination (cross shape in FIG. 7)
Is provided.

However, the spiral swirl flow 61 generated by the impeller 52 toward the outer peripheral direction of the casing is, after passing through the impeller 52, a spiral swirl flow 67 in which the swirl flow 61 is directed toward the pump center. Therefore, the straight rib 65 collides with the straight rib 65 at a substantially right angle (marked by X in FIG. 7) and is decelerated, and the swirling flow 67 decelerated here causes a pressure loss while reaching the discharge pipe 62.

The discharge pressure of the axial flow pump is dominated by the speed of the swirl flow. Therefore, if pressure loss occurs due to deceleration of the swirl flow, the flow speed of the swirl flow is not effectively converted into the discharge pressure. However, there is a problem in that the performance of the axial flow pump is significantly deteriorated.

Therefore, in the water heater using the conventional pump, a large pump is actually used in order to secure the water supply capacity of the liquid and maintain the pump performance.

Further, the pump for circulating the coolant of the vehicle-mounted radiator has a problem that a large space is taken in the engine room because the pump and the electric motor are connected by a V-belt.

[0009]

SUMMARY OF THE INVENTION The present invention has been made to solve the above-mentioned problems, and the swirling flow generated by an impeller can be effectively converted into a discharge pressure to improve the pump performance. The purpose is to provide a pump.

[0010]

An axial flow pump according to a first aspect of the present invention is arranged in one of a cylindrical housing accommodating a stator and a hollow portion of the housing, and an inlet side of a fluid passage is provided. An inlet side casing to be formed, an outlet side casing which is arranged in the other hollow part of the housing and forms an outlet side of a fluid flow path, and an inside casing of the stator, the inlet side casing and the outlet side An impeller rotatably attached to a fixed shaft arranged in a flow path formed by a casing is provided, and a support portion for supporting the fixed shaft on a pump center line is provided in the outlet side casing, and further supports the support portion. In an axial flow pump in which radial ribs are provided on the outlet side casing wall, the radial ribs are spiral curved ribs extending in the outer peripheral direction of the outlet side casing,
In addition, it is characterized in that it is inclined so that it becomes lower toward the outer circumference.

According to this axial flow pump, the swirling flow of the liquid generated by the impeller swirls from the outer peripheral side toward the central portion along the wall of the spiral curved rib radially extending in the outer peripheral direction. While flowing into the discharge pipe, the swirling flow is introduced into the discharge pipe without being decelerated. Further, since the rib height increases toward the central portion, the amount of liquid in the central portion of the casing increases and the water pressure can be increased.

The axial flow pump according to a second aspect of the present invention is the axial flow pump according to the first aspect, wherein the curved rib gradually widens in the outer peripheral direction of the casing.

According to this axial flow pump, not only can the deceleration of the swirl flow be prevented, but the radial rib area provided on the casing wall can be increased, so that the casing strength can be increased and the water resistance of the axial flow pump can be increased. Is improved.

The invention of claim 3 is the axial flow pump according to claim 1 or 2, which is used in a water heater.

According to a fourth aspect of the invention, there is provided the axial flow pump according to the first or second aspect, which is used for circulating a cooling fluid of a vehicle-mounted radiator device.

With the axial flow pump of the present invention, the water supply and circulation performance of the pump can be improved, and the hot water supply capacity of the water heater and the cooling water circulation performance of the vehicle-mounted radiator device can be improved. Therefore, even a small-sized pump has improved performance, and it is possible to reduce the size and weight of the water heater using the pump and reduce the space occupied by the vehicle-mounted radiator device.

[0017]

BEST MODE FOR CARRYING OUT THE INVENTION Embodiments of the present invention will be described with reference to the drawings.

(First Embodiment) FIG. 1 is a vertical sectional view of an axial flow pump 1 according to the first embodiment. The main structure of the pump is the same in the second embodiment described below.

As shown in the figure, an impeller 22 having a shroud 23 and a rotor magnet 24 is fixed to a metal bearing 21 and further rotatably attached to a fixed shaft 2 via a thrust washer 25. Further, outside the casing, a stator 26 is incorporated inside a housing 27 formed by resin molding, and the stator 26 is arranged on the outer peripheral portion so as to face the rotor magnet 24.

The fixed shaft 2 includes a support portion 7 of the inlet side casing 4 on the side of the suction port 28 forming a pump casing,
Both ends thereof are supported by the support portion 6 of the outlet side casing 3 on the downstream side having the discharge port 29, and are arranged on the center line of the axial flow pump 1.

The axial flow pump 1 is assembled by connecting the inlet side casing 4 and the outlet side casing 3 with screws sandwiching an O-ring 20 to form a flow passage 10 in the pump casing, and the liquid is impeller 22. The water is sucked from the suction port 28 by the rotation, is swirled in the flow path 10 in the casing and is flown downstream while being accelerated, and the water supply operation of the axial flow pump 1 is performed.

The outlet side casing 3 on the downstream side of the impeller 22
On the inner surface side of the above, a support portion 6 having a concave portion that fits with one end portion of the fixed shaft 2 and supports one end of the fixed shaft 2 on the center line of the pump casing is provided in the central portion, and the support portion 6 is further provided.
In order to support and fix the above to the central portion of the outlet side casing 3, the outlet side casing inner surface wall 11 is provided with a plurality of spiral curved ribs 5 radially extending in the casing outer peripheral direction.

As shown in FIG. 3, the curved rib 5 is inclined so that it becomes lower toward the outer peripheral portion, and the end of the inclined portion 8 is in contact with the end 11a of the inner wall 11 of the outlet side casing 3. ing.

Regarding the structure of the outlet side casing 3 and the liquid flow of the axial flow pump 1 of the first embodiment, a front view of the outlet side casing 3 of FIG. 2 and a sectional view of FIG. 3 (the upper half is the curved rib 5) Along the bottom, the lower half is a cross section that does not include the curved rib 5)
Will be described in more detail based on.

As shown in the figure, a support portion 6 having a recess for supporting one end of the fixed shaft 2 is disposed in the central portion of the outlet side casing 3, and the support portion 6 is provided in the center of the outlet side casing 3. The wall 11 of the outlet-side casing 3 is provided with a plurality of spiral curved ribs 5 (shaded in FIG. 2) radially extending in the outer peripheral direction in order to support and fix the same to the portion.

The swirling flow 9 generated by the impeller 22 flows downstream in the upstream region of the impeller 22 while exhibiting an outward spiral shape from the center of the axial flow pump 1 toward the outer peripheral side of the pump.

However, the swirling flow 9 flowing downstream in the flow path 10
When passing through the impeller 22 and flowing into the outlet side casing 3, the gas flows over the curved rib 5 and swirls and flows in the outer peripheral portion of the outlet side casing 3, but there are a plurality of spirals provided on the casing wall 11. With the curved rib 5 of, the direction of flow gradually begins to change toward the pump center,
The swirl flow 12 has an inward spiral shape.

The swirling flow 10 that has started to flow toward the center of the pump does not collide with the curved ribs 5 and flows smoothly along the rib walls, so that it does not decelerate, and furthermore, the curved ribs 5 become closer to the center of the pump. Is high, the amount of the swirling flow 10 collected in the central portion of the outlet side casing 3 is large, and the water pressure in the central portion of the outlet side casing 3 can be increased.

Therefore, the swirling flow 9 generated by the impeller 22
Can be introduced into the discharge pipe 14 as a swirl flow 12 flowing along the curved rib 5 of the outlet side casing 3, so that the water flow is not decelerated and pressure loss is prevented,
It can be effectively converted to discharge pressure to improve axial pump performance.

The tubular housing 27 accommodating the stator 26 may be a steel plate, an aluminum die cast, or a resin material to form the outer shell of the pump.

Further, the shroud 23 and the rotor magnet 24 connected to the impeller 22 may be constructed by bonding the shroud 23 and the magnet 24 as separate parts (sintered magnet), but the shroud 23 and the rotor magnet 24 may be connected. Can be integrally molded with a magnetic resin material. Examples of the magnetic resin material include magnetic powder and polyphenylene sulfide (PPS), polyamide resin (nylon), or tetrafluoroethylene resin (registered trademark). Mixtures with plastic resins such as "Teflon") can be used.

(Second Embodiment) Regarding the structure of the outlet side casing 13 and the liquid flow of the axial flow pump 1 of the second embodiment, a front view of the outlet side casing 13 of FIG. 4 and a sectional view of FIG. 5 ( The upper half will be described along the curved rib 18 and the lower half will be described by a cross section not including the curved rib 18).

As shown in the drawing, a support portion 6 having a recess for supporting one end of the fixed shaft 2 is arranged in the center of the outlet side casing 13, and the support portion 6 is provided in the outlet side casing 13.
Outlet side casing 1 for supporting and fixing in the center part inside
The wall 17 of FIG. 3 is provided with a plurality of curvilinear ribs 18 (shown with diagonal lines in FIG. 4) that radially extend in the outer peripheral direction and gradually widen in the outer peripheral direction of the casing.

Also in this embodiment, as in the first embodiment, the swirling flow 15 generated by the impeller 22 is generated.
In the upstream of the impeller 22, the gas flows downstream while showing an outward spiral shape from the central portion of the axial flow pump 1 toward the pump outer peripheral side.

When the swirling flow 15 passes through the impeller 22 and flows into the outlet side casing 13, the swirling flow 15 flows over the curved rib 18 at the outer peripheral portion of the outlet side casing 13. The spiral curving rib 18 gradually starts to change the flow direction toward the center of the pump, and the swirl flow 1 having an inward spiral shape.
It becomes 6.

The swirling flow 16 that has started to flow toward the center of the pump does not collide with the curved rib 18 and flows smoothly along the rib wall so that it does not decelerate, and the curved rib 18 becomes closer to the center of the pump. The swirling flow 1 gathers at the center of the outlet side casing 13 because
The liquid amount of 6 increases, and the flow velocity and water pressure in the central portion of the outlet side casing 13 can be further increased.

Therefore, the swirling flow 1 generated by the impeller 22
5 can be introduced into the discharge pipe 14 as a swirl flow 16 flowing along the curved rib 18 of the outlet side casing 13, so that the water flow is not decelerated, pressure loss is prevented, and the discharge pressure is effectively reduced. It can be converted to improve axial pump performance.

Further, in the curved rib 18 of this embodiment,
Since it has a structure in which the width gradually widens toward the outer peripheral direction, the radial rib area provided on the casing wall 17 can be increased, and the casing strength can be increased to improve the water resistance of the axial flow pump. it can.

Therefore, in the axial flow pump according to the second embodiment, it is possible to obtain an axial flow pump having improved pump performance and improved strength of the pump casing and having excellent durability.

(Third Embodiment) In the third embodiment, the axial flow pump 1 described above is used as a hot water supply pump for a water heater, and a circulating water heater, for example, a hot water supply system for a bath. It can be used for a large amount of hot water and can circulate efficiently in a short time.

(Fourth Embodiment) In the fourth embodiment, the above axial flow pump 1 is used in a vehicle-mounted radiator device and is used for circulating a cooling liquid of a water-cooled engine such as an automobile. It is a thing.

In this embodiment, the cooling water that has exchanged the heat generated in the engine is circulated in the engine section and the radiator section by the axial flow pump, and the heat can be dissipated from the radiator section. To keep the
It is possible to prevent problems such as piston burning and abnormal fuel combustion due to overheating of the engine.

Further, in this axial flow pump 1, since the motor part for driving the pump is integrated in the pump,
A conventional motor for driving a pump and a transmission belt are no longer required, and it is possible to further reduce the space and weight in the engine room.

As described above, in the axial flow pump of the present invention and the apparatus using the same, liquid transportation and circulation performance are significantly improved, reliable operation of each apparatus is possible, and further, the apparatus is small, It can also be made lighter.

Of course, the axial flow pump can be used for various devices other than the water heater and the vehicle-mounted radiator device described in the above embodiment.

[0046]

As described above, in the axial flow pump of the present invention, the tubular housing accommodating the stator and one of the hollow portions of the housing are arranged to form the inlet side of the fluid passage. An inlet side casing that is disposed in the other of the hollow portions of the housing and that forms an outlet side of a fluid flow path; and an inlet side casing and an outlet side casing that are inside the stator. A vane wheel rotatably attached to a fixed shaft arranged in the flow path formed by the above, a support portion for supporting the fixed shaft on the pump center line is provided in the outlet side casing, and a radial shape for supporting the support portion is provided. In the axial flow pump in which the rib is provided on the outlet side casing wall, the radial rib is a spiral curved rib extending in the outer peripheral direction of the outlet side casing,
In addition, since the curved rib is an axial flow pump that gradually decreases in width toward the outer circumference of the casing, the swirling flow by the impeller is effectively converted into discharge pressure. (EN) Provided is an axial flow pump which has an excellent effect of improving pump performance and further improving durability, and which is suitable for circulating a cooling water of a water heater of a water heater or a radiator device mounted on a vehicle. it can.

[Brief description of drawings]

FIG. 1 is a vertical sectional view of an axial flow pump according to an embodiment of the present invention.

FIG. 2 is a front view of an outlet side casing of the first embodiment.

FIG. 3 is a cross-sectional view taken along the curved rib of the same.

FIG. 4 is a front view of an outlet side casing of the second embodiment.

FIG. 5 is a sectional view taken along the curved rib of the above.

FIG. 6 is a vertical cross-sectional view of a conventional axial flow pump.

FIG. 7 is a front view of an outlet side casing of a conventional example.

FIG. 8 is a sectional view taken along the line A-O-B of the same.

[Explanation of symbols] 1 ... Axial flow pump 2 ... Fixed axis 3, 13 ... Outlet side casing 4 ... Inlet side casing 5,18 ... Curved rib 6, 7 ... Fixed shaft support of casing 8: Curved rib inclination 9, 12, 15, 16 ... Swirl flow 10 ... Channel 11, 17 ... Inner wall of outlet casing 14 ... Discharge pipe 22 ... Impeller 27 ... Housing 28 ... Inhalation port 29 ... Discharge port

Claims (4)

[Claims] 1. A tubular housing that houses a stator, an inlet-side casing that is arranged in one of the hollow portions of the housing and forms an inlet side of a fluid flow path, and the other of the hollow portions of the housing. An outlet-side casing that is arranged and forms the outlet side of the fluid flow path; and a fixed shaft that is inside the stator and that is arranged in the flow path formed by the inlet-side casing and the outlet-side casing. An axial flow pump provided with an impeller freely attached, a support portion for supporting the fixed shaft on a pump center line provided in the outlet side casing, and radial ribs for supporting the support portion provided in the outlet side casing wall. In the axial flow, the radial rib is a spiral curvilinear rib extending in the outer peripheral direction of the outlet side casing, and is inclined so that it becomes lower toward the outer periphery. pump. 2. The axial flow pump according to claim 1, wherein the curved rib gradually widens in the outer peripheral direction of the casing. 3. The axial flow pump according to claim 1, which is used in a water heater. 4. The axial flow pump according to claim 1 or 2, which is used for circulating a cooling fluid of a vehicle-mounted radiator device.