JPH0849685A - Magnetic coupling pump - Google Patents

Abstract

PURPOSE:To hardly apply a thrust load on a bearing for supporting an impeller, to improve pump efficiency through reduction of rotation resistance, to improve durability, and to suppress the increase of size. CONSTITUTION:A bearing 14 is located in a pump chamber 11 having a suction port 12a and a delivery port 12b. An impeller 13 on the obverse side of which an impeller plate 13a is disposed and on the reverse side of which a magnet 13b is fixed is rotatably supported. The impeller 13 is rotated by means of a magnetic force exerted from the reverse side of the impeller 13 at the periphery of the pump chamber 11 and attracting a magnet 13b to feed cooling water L. A back pressure space 20 is formed between the reverse side of the impeller 13 and the inner peripheral surface of the pump chamber 11. An introduction flow passage 21 through which a part of the cooling water L on the delivery port 12b side is guided is connected to the back pressure space 20.

Description

Detailed Description of the Invention

[0001]

BACKGROUND OF THE INVENTION 1. Field of the Invention The present invention relates to a magnetic coupling pump used for a water pump or the like arranged in a cooling circuit of an automobile.

[0002]

2. Description of the Related Art Conventionally, as magnetic coupling pumps of this type, Japanese Utility Model Laid-Open No. 56-88989 and Japanese Utility Model Publication No. 5 have been used.
As shown in FIG. 4, the pump chamber 1 and the motor chamber 6 are provided, and the housing 2 of the pump chamber 1 has a suction port 2a through which the fluid L flows in, as shown in FIG.
A discharge port 2b for discharging the fluid L is formed, and a plurality of bearings 5 made of bushes and a shaft 4 fixed to the housing 7 of the motor chamber 6 are used in the pump chamber 1 to form a plurality of surfaces on the surface side. The impeller 3 having the vane plate 3a and the annular magnet 3b fixed to the back side is rotatably supported. The annular magnet 3b has an NS pole magnetized in its circumferential direction, and a bearing 5 made of a bush is fixed to the vane plate 3.

Further, the motor chamber 6 is constructed by winding a stator coil 9 around a plurality of cores 8 in a housing 7. The motor configured in the motor chamber 6 is an axial air gap type brushless DC.
It is a motor.

By energizing each stator coil 9, the stator coil 9 is excited so as to generate a magnetic force for attracting the magnet 3b, and the impeller 3 rotates,
The fluid L was to be delivered.

However, in this magnetic coupling pump P0, when the fluid L is fed, the magnet 3b fixed to the impeller 3 is used.
Is subjected to the action of being attracted to the motor chamber 6 side by the magnetic force of the stator coil 9, and the impeller 3 rotates, so that the bearing 5 supporting the impeller 3 has the impeller 3
A thrust load acts in the axial direction of.

Therefore, the bearing 5 supporting the impeller 3
When the thrust load is applied, the rotational resistance of the impeller 3 is increased, and the pump efficiency and durability are reduced.

To address this, Japanese Patent Laid-Open No. 59-21646
As described in Japanese Patent No. 0, Japanese Utility Model Laid-Open No. 56-90496, etc., it is conceivable to dispose a magnetic body that attracts in the opposite direction around the magnet of the impeller.

However, as shown in FIG. 4, in the case of the pump P0 in which a plurality of vane plates 3a are formed on the surface side of the impeller 3, when a magnetic body for attracting the magnet 3b is arranged, It is necessary to dispose the magnetic body so that it does not interfere with the blade plate 3a, and the magnetic body is arranged away from the magnet 3b. Then, in order to ensure a predetermined attracting force, the magnetic body must be made large, and the volume of the pump chamber 1 must be made large, so that the pump P0 becomes large in size and the space is limited. Not desirable when placed in a car.

The present invention is intended to solve the above-mentioned problems, and it is difficult for a thrust load to be applied to the bearings supporting the impeller, the rotation resistance can be reduced to improve pump efficiency, and the durability can be improved. Can improve the
Moreover, it aims at providing the magnetic coupling pump which can suppress enlargement.

[0010]

A magnetic coupling pump according to the present invention includes a bearing in a pump chamber having an intake port and a discharge port, a vane plate disposed on the front surface side, and a vane plate disposed on the rear surface side. An impeller having a magnet fixed thereto is rotatably supported, and the impeller is rotated by a magnetic force that acts from the back surface side of the impeller around the pump chamber to attract the magnet, thereby rotating the fluid. A magnetic coupling pump for feeding, wherein a back pressure space is provided between a surface on the back surface side of the impeller and an inner circumferential surface of the pump chamber, and a part of the fluid on the discharge port side is It is characterized in that it has an introduction flow path leading to the back pressure space.

It is desirable that the bearing has an annular shape and is disposed around the back pressure space between the vicinity of the outer peripheral edge on the back surface side of the impeller and the inner peripheral surface of the pump chamber.
Further, it is desirable to form a concave portion that constitutes a part of the introduction flow path in the bearing.

[0012]

In the magnetic coupling pump according to the present invention, when the magnetic force for adsorbing the magnet provided in the impeller acts, the impeller rotates and the fluid flowing from the suction port of the pump chamber is delivered from the discharge port. Becomes

The discharge port is provided with an introduction flow passage for introducing the fluid into the back pressure space between the back surface of the impeller and the inner peripheral surface of the pump chamber. , The discharge pressure acts on the back side of the impeller as back pressure. This back pressure acts from the back surface side to the front surface side of the impeller so as to oppose the thrust load acting on the bearing, so that the thrust load acting on the bearing is reduced.

Further, as the structure of the pump, there is simply a back pressure space arranged between the back surface side of the impeller and the inner peripheral surface of the pump chamber, and an introduction flow passage for causing the discharge pressure to act on the back pressure space. Unlike the case where the magnetic body is separately provided so as not to interfere with the blade plate of the impeller, it is possible to suppress the increase in size of the pump chamber as much as possible.

When the bearing is annularly arranged around the back pressure space between the vicinity of the outer peripheral edge on the back surface side of the impeller and the inner peripheral surface of the pump chamber, a conventional shaft is arranged. Since it is not necessary to do so, it is possible to secure a large back pressure space while suppressing an increase in the size of the pump chamber.

Further, in the case where the concave portion which constitutes a part of the introduction flow passage is formed in the annular bearing itself, the space for the introduction flow passage can be small, and hence the size of the pump chamber can be further suppressed. It will be possible.

[0017]

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

The magnetic coupling pump P1 of the embodiment of the present invention is
As shown in FIG. 1, the water pump is provided in a cooling circuit of an automobile, and includes a pump chamber 11 and a motor chamber 16 as in the conventional case.

The housing 12 of the pump chamber 11 is formed with a suction port 12a through which the cooling water L flows in and a discharge port 12b through which the cooling water L is discharged.

Further, a substantially disk-shaped impeller 13 is arranged in the pump chamber 11. The impeller 13 is provided with a plurality of impeller plates 13a on its front surface side and has an annular shape on its rear surface side. Magnet 13b
Has been fixed. The magnet 13b has an NS pole magnetized in its circumferential direction.

This impeller 13 has an annular bearing 14 on the outer peripheral side of the magnet 13b at the outer peripheral edge on the back side.
It is rotatably supported in the pump chamber 11. Bearing 14
In the case of the embodiment, the bush is made of a bush made of phosphor bronze, carbon, or the like, and is fixed to the partition wall 17b of the housing 17 on the motor chamber 16 side that constitutes the inner peripheral surface of the pump chamber 11.

In the case of the embodiment, the magnet 13 between the back surface of the impeller 13 and the inner peripheral surface of the pump chamber 11 is used.
The inside of b is the back pressure space 20, and as shown in FIGS.
On the lower surface of the bearing 14 on the side of the discharge port 12b, the groove 14a
Is formed, and the concave groove 14a constitutes a part of the introduction flow path 21.

The introduction flow passage 21 includes a recess 12c around the bearing 14 on the discharge port 12b side of the housing 12, a recess 14a of the bearing 14, a magnet 13b, and a housing 17 on the inner peripheral surface of the pump chamber 11 (a partition wall described later). 17b) and a gap.

The motor chamber 16 is constructed by winding a stator coil 19 around a plurality of cores 18 in a housing 17. The motor configured in the motor chamber 16 is an axial air gap type brushless DC motor similar to the conventional one.

The honing 17 includes a main body 17a which covers the periphery of the stator coil 19, and a partition wall 17b which constitutes the inner peripheral surface of the pump chamber 11 and covers the stator coil 19 and which is made of a non-magnetic material and a non-conductive material. ,,. The housing 12 is a predetermined number of bolts 1
It is integrated by 5.

In the pump P1 of this embodiment, by energizing each stator coil 19,
Are excited to generate a magnetic force that attracts the magnet 13b, the impeller 13 rotates, and the suction port 12 of the pump chamber 11
The cooling water L that has flowed in from a is supplied from the discharge port 12b.

At this time, the impeller 13 is provided on the discharge port 12b side.
Space 20 between the back side of the pump and the inner peripheral surface of the pump chamber 11
Since the recess 12c forming a part of the introduction flow path 21 for introducing the cooling water L is opened, the discharge pressure of the cooling water L is
The discharge pressure is guided to the back pressure space 20 and acts on the back surface side of the impeller 13 as back pressure. This back pressure acts from the back surface side to the front surface side of the impeller 13 so as to oppose the thrust load acting on the bearing 14, so that the thrust load acting on the bearing 14 is reduced. The back pressure acting at this time is back pressure = (discharge pressure−suction pressure) × area of the back pressure space 20 (area surrounded by the magnet 13b on the back surface of the impeller 13).

The bearing 1 supporting the impeller 13
Since it becomes difficult to apply a thrust load to 4, the impeller 1
The rotation resistance of 3 can be reduced, the pump efficiency can be improved, and the durability of the pump P1 can be improved.

Further, as the structure of the pump P1, the back pressure space 20 arranged between the back surface of the impeller 13 and the inner peripheral surface of the pump chamber 11 and the discharge pressure are applied to the back pressure space 20. Introductory flow path 21 (the discharge port 12b of the housing 12
(A concave portion 12c around the bearing 14 on the side, a concave portion 14a of the bearing 14 and a gap between the magnet 13b and the housing partition wall 17b on the inner peripheral surface of the pump chamber 11) are provided. Unlike the case where the magnetic body is provided so as not to interfere with, the increase in size of the pump chamber 11 can be suppressed as much as possible.

Furthermore, as in the embodiment, the bearing 14
Is arranged around the back pressure space 20 between the vicinity of the outer peripheral edge on the back surface side of the impeller 13 and the inner peripheral surface of the pump chamber 11 as an annular shape, the shaft 4 like the conventional pump P0. Since it is not necessary to arrange the pump chamber 11, it is possible to secure a large back pressure space 20 while suppressing an increase in the size of the pump chamber 11.

Further, when the concave portion 14a forming a part of the introduction flow passage 21 is formed in the annular bearing 14 itself, the space for the introduction flow passage 21 can be made small, so that the pump chamber 11 can be further improved. Therefore, it is possible to suppress the increase in size.

It should be noted that although it is slightly larger than the pump P1 of the embodiment, it may be configured as the pump P2 shown in FIG.

The pump P2 has the same structure as the conventional pump P0 (the same members are designated by the same reference numerals), but an annular magnet 3b fixed to the back surface of the blade plate 3 is used.
Between the rear surface of the vane plate 3 and the bearing 5 and the pump chamber 1
A back pressure space 30 is formed between the back pressure space 30 and the inner peripheral surface of, and an introduction flow path 31 extending from the discharge port 2b and penetrating the housing 7 is formed in the back pressure space 30.

Since the back pressure space 30 is provided around the shaft 4 and the bearing 5 in the pump P2, the pump P2 is slightly larger than the pump P1. However, the pump P2 is separately magnetized so as not to interfere with the impeller vane plate. Unlike the case where the body is provided, the size of the pump chamber 1 can be suppressed as much as possible, and the thrust load is less likely to be applied to the bearing 5 that supports the impeller 3. The dynamic resistance is reduced, the pump efficiency can be improved, and the durability of the pump P2 can be improved.

In the pumps P1 and P2, the blade plate 3
The case where an axial air gap type brushless DC motor is used as a drive device for rotating 13 has been described, but the magnets 3b and 13b are operated by acting from the back side of the impeller 3 and 13 around the pump chamber 1 and 11. As long as the impellers 3 and 13 can be rotated by the magnetic force to be attracted, as described in Japanese Utility Model Laid-Open No. 56-88989, a prime mover for rotating a magnet is separately provided as a driving device. The present invention can also be applied to such a pump.

In the pump P1 of the embodiment, the housing 12 and the bearing 14 are not provided with the recesses 12c and 14a, but the introduction passage 31 like the pump P2 is provided so that the discharge pressure acts on the back pressure space 20. May be.

[0037]

According to the magnetic coupling pump of the present invention, the back pressure space disposed between the back side of the impeller and the inner peripheral surface of the pump chamber, and the introduction passage for allowing the discharge pressure to act on the back pressure space. Unlike the case where a magnetic body is separately provided so as not to interfere with the blade plate of the impeller, it is possible to suppress the enlargement of the pump chamber as much as possible.

Then, the discharge pressure of the fluid is introduced into the back pressure space, and the discharge pressure acts as a back pressure on the back surface side of the impeller. This back pressure counters the thrust load acting on the bearing, Since it acts from the back side to the front side of the impeller, the thrust load acting on the bearing is reduced, the rotation resistance can be reduced, the pump efficiency can be improved, and the durability can be improved. As a result, it is possible to prevent the pump from increasing in size.

Furthermore, when the bearing is formed in an annular shape and is arranged around the back pressure space between the vicinity of the outer peripheral edge on the back surface side of the impeller and the inner peripheral surface of the pump chamber, a conventional shaft is arranged. Since it does not need to be installed, it is possible to secure a large back pressure space while suppressing an increase in the size of the pump chamber.

Further, in the case where the concave portion which constitutes a part of the introduction flow passage is formed in the annular bearing itself, the space for the introduction flow passage can be made small, so that the size of the pump chamber can be further suppressed. It will be possible.

[Brief description of drawings]

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

FIG. 2 is a perspective view of a bearing used in the embodiment.

FIG. 3 is a sectional view showing another embodiment.

FIG. 4 is a cross-sectional view showing a conventional example.

[Explanation of symbols]

 1.11 ... Pump chamber, 2a / 12a ... Suction port, 2b / 12b ... Discharge port, 3.13 ... Impeller, 3a / 13a ... Blade plate, 3b / 13b ... Magnet, 514 ... Bearing, 14a ... Recessed portion , 20/30 ... Back pressure space, 21/31 ... Introducing channel, L ... (Fluid) cooling water, P0 / P1 / P2 ... Magnetically coupled pump.

Claims (3)

[Claims] 1. An impeller in which a bearing is interposed, a vane plate is disposed on the front surface side, and a magnet is fixed on the rear surface side in a pump chamber having an intake port and a discharge port, is rotatable. A magnetically coupled pump that is supported and that rotates the impeller by a magnetic force that acts from the back side of the impeller around the pump chamber and attracts the magnet, and that supplies fluid. A back pressure space is provided between the surface on the back surface side and the inner peripheral surface of the pump chamber, and an introduction flow path for guiding a part of the fluid on the discharge port side to the back pressure space is provided. A magnetic coupling pump characterized by the above. 2. The bearing is arranged in an annular shape around the back pressure space between the vicinity of the outer peripheral edge on the back surface side of the impeller and the inner peripheral surface of the pump chamber. The magnetic coupling pump according to claim 1. 3. The magnetic coupling pump according to claim 2, wherein the bearing is provided with a recess that forms a part of the introduction flow path.