JP3203542B2 - Bearing structure of magnetic coupling pump - Google Patents

Description

DETAILED DESCRIPTION OF THE INVENTION

[0001]

The present invention relates to a magnetic coupling pump,
More specifically, the present invention relates to a magnetic coupling pump used as a water pump disposed in a cooling circuit of an automobile.

[0002]

2. Description of the Related Art FIG. 3 is a sectional view of a conventional magnetic coupling pump.

In this conventional magnetic coupling pump, an impeller 2, a stator 3 for rotating the impeller 2, and a partition 4 for separating the impeller 2 from the stator 3 are provided in a pump housing 1.
And a bearing 5 provided on the partition wall 4 to rotatably support the impeller 2.

The impeller 2 has a substantially disk-shaped main body 21 made of brass or resin such as PPS (polyphenylene sulfide resin) having a plurality of blades 21 a, and a main body 2.
1 has a rotating shaft portion 24 made of stainless steel protruding from the center of the back surface, and a magnetic plate 22 for strengthening magnetic force and a permanent magnet portion 23 provided in a concave portion 21 b of the main body portion 21. In addition, the concave portion 21b is formed in a circumferential direction around the rotation shaft portion 24.

[0005] The stator 3 is disposed around the rotating shaft 24 and is configured to rotate the impeller 2 by applying a magnetic attraction to the permanent magnet 23. Specifically, each end face 3 of the stator 3 is opposed to the permanent magnet portion 23.
A plurality of stator cores 31 in which 1a are arranged in a circumferential direction;
Stator coil 3 wound around each stator core 31
And an excitation current is supplied to each of the stator coils 32 to generate a rotating magnetic field on the end faces 31 a of the plurality of stator cores 31. Reference numeral 33 denotes a coil terminal, 34 denotes a control board having a circuit for controlling the exciting current, and 35 denotes a magnetic plate for enhancing magnetic force.

The partition 4 is made of a resin material such as PPS,
It is arranged close to the main body 21 to reduce the size of the pump.

The bearing 5 includes a first bearing member 51 disposed on the main body 21 side of the impeller 2 and a second bearing member 52 disposed on the tip side of the rotating shaft 24. The first and second bearing members 51 and 52 are each made of a resin material or a copper-based sintered alloy material and have a hollow cylindrical shape.
The shafts 24 are press-fitted at intervals in the axial direction into the bottomed cylindrical rotating shaft housing 4a, and the rotating shaft 24 is rotatably supported by the inner peripheral surfaces 51a and 52a. Further, the first bearing member 51
Is formed with an annular sliding contact surface 51b slidingly contacting the stainless flat washer 6 mounted on the rotating shaft portion 24.

[0008]

However, in the conventional magnetic coupling pump, the component of the magnetic attraction force acting on the impeller 2 in the direction from the permanent magnet portion 23 of the impeller 2 toward the stator core 31 (thrust direction). Because of the large size, the impeller 2 is formed in the annular sliding contact surface 5 of the first bearing member 51.
Sliding surface 51 resulting from rotation while pressing on 1b
b, the back surface of the main body 21 of the impeller 2 is
And the discharge rate of the pump decreases early.

SUMMARY OF THE INVENTION In view of the above problems, it is an object of the present invention to extend the life of a bearing in the thrust direction and suppress a decrease in pump discharge.

[0010]

In order to solve the above-mentioned problems, a bearing structure of a magnetic coupling pump according to the present invention includes an impeller, a stator for rotating the impeller, and an impeller in a pump housing. A magnetic coupling pump comprising a partition separating the stator and a bearing provided on the partition and rotatably supporting the impeller, wherein the impeller includes:
A substantially disk-shaped main body, a rotating shaft protruding from the center of the back surface of the main body, and a permanent body disposed on the main body so as to be located on a circumference centered on the rotating shaft. And a magnet portion, wherein the stator is disposed around the rotation shaft portion,
A magnetic coupling pump configured to rotate the impeller by applying a magnetic attractive force to the permanent magnet portion, wherein the bearing has an annular sliding contact surface that is in sliding contact with the back surface side of the main body portion; The part and the bearing are provided with a pair of annular sliding contact spare surfaces which start sliding contact with each other when the annular sliding contact surface is worn by a predetermined amount.

[0011]

In the bearing structure of the magnetic coupling pump according to the present invention, the pair of annular sliding contact spare surfaces rotate while the impeller presses the annular sliding contact surface by the thrust direction component of the magnetic attraction force. When the sliding surfaces are worn by a predetermined amount due to this, sliding starts with each other. After the start of the sliding contact, the preliminary sliding contact surface of the bearing receives the pressing force of the impeller due to the thrust direction component of the magnetic attraction force in a shared manner with the worn sliding contact surface. For this reason, the wear of the worn sliding contact surface is suppressed, the life of the bearing in the thrust direction is extended, and a decrease in the pump discharge amount can be suppressed.

[0012]

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

FIG. 1 is a sectional view of a magnetic coupling pump according to an embodiment of the present invention. The magnetic coupling pump according to this embodiment is configured similarly to the above-described conventional magnetic coupling pump shown in FIG. 3 except that a bearing structure including a rotating shaft portion of an impeller and a bearing is different.

That is, the magnetic coupling pump of this embodiment is
Within a pump housing 1, an impeller 2, a stator 3 for rotating the impeller 2, a partition 4 separating the impeller 2 from the stator 3, and a bearing provided on the partition 4 to rotatably support the impeller 2. 5 is provided.

The impeller 2 has a substantially disc-shaped main body 21 made of brass or resin such as PPS (polyphenylene sulfide resin) having a plurality of blades 21a;
1 has a rotating shaft portion 24 made of stainless steel protruding from the center of the back surface, and a magnetic plate 22 for strengthening magnetic force and a permanent magnet portion 23 provided in a concave portion 21 b of the main body portion 21. In addition, the concave portion 21b is formed in a circumferential direction around the rotation shaft portion 24.

Here, the rotating shaft portion 24 has the same diameter as that of the conventional rotating shaft portion 24 from the main body portion 21 side to the distal end, whereas, as shown in FIG. 2
One side is a large diameter part 24a, and the tip side is a small diameter part 24b.

The stator 3 is disposed around the rotating shaft 24 and is configured to apply a magnetic attraction to the permanent magnet 23 to rotate the impeller 2. Specifically, each end face 3 of the stator 3 is opposed to the permanent magnet portion 23.
A plurality of stator cores 31 in which 1a are arranged in a circumferential direction;
Stator coil 3 wound around each stator core 31
And an excitation current is supplied to each of the stator coils 32 to generate a rotating magnetic field on the end faces 31 a of the plurality of stator cores 31. Reference numeral 33 denotes a coil terminal, 34 denotes a control board having a circuit for controlling the exciting current, and 35 denotes a magnetic plate for enhancing magnetic force.

The partition 4 is made of a resin material such as PPS,
It is arranged close to the main body 21 to reduce the size of the pump.

The bearing 5 comprises a first bearing member 51 provided on the main body 21 side of the impeller 2 and a second bearing member 52 provided on the tip end side of the rotating shaft 24. The first and second bearing members 51 and 52 each have a hollow cylindrical shape and are made of a resin material or a copper-based sintered alloy material.
The shafts 24 are press-fitted at intervals in the axial direction into the bottomed cylindrical rotating shaft housing 4a, and the rotating shaft 24 is rotatably supported by the inner peripheral surfaces 51a and 52a.

Here, the first bearing member 51 rotatably supports the large-diameter portion 24a of the rotary shaft portion 24, while the second bearing member 52 supports the small-diameter portion 24b of the rotary shaft portion 24. Support rotatably. Further, the first bearing member 51 has, like the first bearing member 51 of the above-mentioned conventional example, an annular sliding contact surface 51b which slides on the stainless flat washer 6 mounted on the rotating shaft portion 24. Is formed. On the other hand, the second bearing member 52 is configured to rotatably support the rotating shaft portion 24 only on the inner peripheral surface 52a, whereas the second bearing member 52 of the above-described conventional example is configured as shown in FIG. As shown in FIG.
The annular end surface 52b is arranged to face the annular step surface 24c formed between the large diameter portion 24a and the small diameter portion 24b with a slight gap 7 (for example, about 200 μm). The pair of step surfaces 24c and the end surface 52
When the impeller 2 rotates while pressing the sliding contact surface 51b with the thrust component of the magnetic attraction force, the sliding contact surfaces 51b start sliding contact with each other when the sliding contact surface 51b is worn by the size of the gap 7. It is configured as a pair of sliding contact spare surfaces.
When the pair of preliminary sliding surfaces 24c and 52b starts sliding contact, the preliminary sliding surface 52 of the second bearing member 52 will be described.
b receives the pressing force of the impeller 2 due to the thrust component of the magnetic attraction in a shared manner with the sliding contact surface 51b, and the abrasion of the sliding contact surface 51b is suppressed. That is, as shown in FIG. 2, a change in the amount of wear of the sliding contact surface 51b with respect to time is suppressed when the amount of wear reaches the dimension of the gap 7 as an inflection point. The life of the pump 51 in the thrust direction is extended, and a decrease in the pump discharge amount can be suppressed.

As described above, according to the bearing structure of the magnetic coupling pump according to the present embodiment, when the annular sliding contact surface 51b is worn by a predetermined amount due to the thrust component of the magnetic attraction force, a pair of annular sliding contacts is formed. Since the preliminary surfaces 24c and 52b start slidingly contacting each other, the preliminary sliding surface 52b of the bearing 5 thereafter reduces the thrust direction component of the magnetic attraction force to the worn sliding surface 5b.
1b. Therefore, the abrasion of the worn sliding contact surface 51b is suppressed, the life of the bearing 5 in the thrust direction is extended, and a decrease in the pump discharge amount can be suppressed.

[Brief description of the drawings]

FIG. 1 is a cross-sectional view of a magnetic coupling pump according to one embodiment.

FIG. 2 is a graph for explaining the operation and effect;

FIG. 3 is a sectional view of a conventional magnetic coupling pump.

[Explanation of symbols]

 DESCRIPTION OF SYMBOLS 1 Pump housing 2 Impeller 21 Main body part 23 Permanent magnet part 24 Rotating magnet part 24c Step surface (preliminary sliding contact surface) 3 Stator 4 Partition wall 5 Bearing 51b Sliding contact surface 52b End surface (preliminary sliding contact surface)

──────────────────────────────────────────────────続 き Continuation of the front page (56) References JP-A-5-21197 (JP, A) JP-A-59-591 (JP, A) JP-A-51-52502 (JP, A) JP-A 48-197 9401 (JP, A) JP-A-61-25990 (JP, A) JP-A-59-586 (JP, U) (58) Fields investigated (Int. Cl. ⁷ , DB name) F04D 13/02 F04D 29 / 04

Claims (2)

(57) [Claims] 1. An impeller, a stator for rotating the impeller, a partition separating the impeller and the stator, and a rotor provided in the partition for rotatably supporting the impeller in a pump housing. And a bearing, wherein the impeller has a substantially disk-shaped main body, a rotating shaft protruding from the center of the rear surface of the main body, and a center of the rotating shaft. And a permanent magnet portion disposed on the main body portion so as to be positioned in a circumferential direction. The stator is disposed around the rotation shaft portion, and acts on the permanent magnet portion by applying a magnetic attractive force. A magnetic coupling pump having an annular sliding contact surface that slides on a back side of the main body, wherein the annular sliding contact is provided on the rotating shaft portion and the bearing. When the contact surfaces are worn by a predetermined amount, sliding contact starts. Bearing structure of a magnetic coupling pump, characterized in that a sliding contact preliminary surface of the annular. 2. The bearing structure for a magnetically coupled pump according to claim 1, wherein the partition wall and the impeller are arranged close to each other.