JPH0135547Y2 - - Google Patents

Description

[Detailed Description of the Invention] The present invention relates to a liquid-sealed underwater motor equipped with an expansion absorption device using a conical coil spring and a diaphragm.

A sealed liquid submersible motor is filled with a sealed liquid, and as the motor generates heat during operation, the sealed liquid and a small amount of gas contained therein are heated and expand. In order to absorb this expansion and balance the internal and external pressures of the motor, for example, a diaphragm is used as a partition, and in order to take a sufficient amount of deformation of the diaphragm and keep the diaphragm in a reasonable shape, the edge of the container-shaped diaphragm is attached to the motor body. A conical coil spring with strong lateral rigidity is inserted between the presser plate and the bottom of the diaphragm.

A submersible motor equipped with such an expansion/absorption device for sealed liquid will be explained with reference to the drawings. FIG. 1 is a longitudinal sectional view of a conventional example. However, the figure is shown rotated 90 degrees, and the right side of the figure is the top. A stator 2 is fixed in a middle cylindrical frame 1 made of sheet metal, and ring-shaped upper frame side plates 3 and lower frame side plates 4 are press-fitted and fixed on both sides. An upper bracket 6 is fitted into the upper frame side plate 3 via a sealing ring 5, and an upper radial metal 7 is fitted into the upper bracket 6 via a detent pin (not shown). A lower bracket 9 is fitted into the lower frame side plate 4 via a sealing ring 8 and fixed with bolts 19, and a lower radial metal 10 is fitted into the lower bracket 9 via a locking pin (not shown). A motor shaft 12 is slid into the upper radial metal 7 and the lower radial metal 10 via the stator 2 and the stator can 27, to which a rotor 11 is press-fitted and fixed with a slight gap from the stator can. . A balance ring 13 is press-fitted onto the motor shaft 12 and is used to adjust dynamic balance.

The lower end of the motor shaft 12 is press-fitted with a rotating disk at the upper end of a self-aligning thrust bearing 14 via a key 15 . The self-aligning thrust bearing 14 can swing freely because the sliding member supported by the leveling disk 14a is supported by the hemispherical surface at the upper end of the adjusting screw 16 so that the leveling disk 14a can swing freely. The submersible motor is supported by the thrust caused by the operation of the pump connected to the submersible motor, and the weight of the shaft joint at the end of the motor shaft 12 (not shown), the rotor 11, the motor shaft 12, etc. as loads. Asian Screw 1
6, the motor shaft 12 is screwed to the thrust housing 17 of the motor outer frame after adjusting the position thereof, and fixed by a lock nut 18. Thrust housing 1
7 is screwed into the lower bracket 9 using a sealant to fix the female thread at the end thereof, and is prevented from rotating with a dowel pin 20. A shaft sealing device such as an oil seal 21 is fitted into the upper bracket 6 to seal the motor shaft 12. Following the oil seal 21, a cylindrical seal cover 22 is press-fitted into the upper bracket 6.
The motor shaft 12 is mounted on the cylindrical outer periphery of the seal cover 22.
The sand slinger 23 press-fitted into the seal cover 22 comes into contact with the outer periphery of the seal cover 22 at a small distance, and also acts as a drainer due to centrifugal force. The coil 24 of the stator 2 is connected to a three-core flat cable connector 25 , and the three-core flat cable connector 25 penetrates a circular hole provided in the axial direction of the upper frame side plate 3 to ensure watertightness with a sealing means, and the cable 26 It is connected to and receives three-phase AC power from the outside. Both sides of a cylindrical stator can 27 made of sheet metal are welded to the upper frame side plate 3 and the lower frame side plate 4 so as to be in contact with the inner circumference of the stator 2 .
The hexagonal hole plug 28 is screwed into the filled water inlet 29 of the upper bracket 6, which is disposed obliquely upward so as to be located at the highest position in the motor interior space.

A diaphragm 30 is fitted into the lower part of the thrust housing 17, and a holding plate 32 with a hole 31 formed in a cylindrical hole at the lower end of the thrust housing 17 is press-fitted so as to press the outer flange of the diaphragm 30. is fixed in a watertight manner. A conical coil spring 34 is inserted in a compressed state between the holding plate 32 and the spring receiving plate 33 that is in contact with the bottom surface of the diaphragm 30. A boss 30a provided at the center of the diaphragm 30 is positioned and fitted into the center hole of the spring receiving plate 33. The above diaphragm 30,
The conical coil spring 34 and the presser plate 32 constitute an expansion absorbing device that absorbs the internal pressure of the motor.

The conical coil spring 34 has a small contact length when compressed, has strong lateral rigidity, and has almost the same shape as the diaphragm 3.
0 in the direction of the central axis.If the conical coil spring 34 has a large number of turns, the spiral shape of the coil deforms approximately symmetrically around the center, but if the number of turns is small and the coil contracts close to its limit, it will deform into a conical shape. The conical coil spring 34 is deformed so as to shift laterally, and therefore the top surface of the conical coil spring 34 may not be horizontal and may not come into full contact with the diaphragm 30. When the return is repeated, or when the diaphragm 30 and the conical coil spring 34 move rapidly, the cylindrical portion 33a may be in contact with the conical coil spring 34 and the spring receiving plate 33. is provided to prevent the conical coil spring 34 from coming off the spring receiving plate 33,
Since the height of the cylindrical portion 33a is low and there is a gap between the outer diameter of the large end of the conical coil spring and the cylindrical portion 33a,
The conical coil spring 34 may come off the spring receiving plate 33, or because the center hole of the spring receiving plate 33 is inserted into the boss 30a of the diaphragm 30 with a gap, it may come off the boss 30a. There was a drawback that the diaphragm 30 would not work or would be damaged thereafter.

As mentioned above, the present invention eliminates the drawbacks caused by the disengagement of the contact parts between the diaphragm and the spring receiving plate, and between the spring receiving plate and the conical coil spring, and is equipped with an expansion absorption device that allows the diaphragm to move while maintaining its correct posture. The purpose is to obtain an underwater motor.

In order to achieve the above object, the present invention includes a diaphragm, a spring receiving plate, a holding plate, and a conical coil spring. The diaphragm is dish-shaped and has a center hole, and a spring positioning part is provided at the center of the holding plate.The diaphragm is watertightly attached to the lower part of the outer frame of the underwater motor so as to partition the inside and outside of the motor, and the center hole is fitted into the boss on the bottom of the diaphragm. A spring receiving plate is held in contact with the bottom of the diaphragm, a large end of the conical coil spring is brought into contact with the spring receiving plate, and a small end is engaged with a spring positioning portion of the holding plate, In a liquid-sealed submersible motor in which the conical coil spring is compressed and the holding plate is fixed to the lower part of the outer frame of the underwater motor, the large end of the conical coil spring is pushed outward at multiple points on the outer periphery of the spring receiving plate. This is a liquid-sealed submersible motor that is more involved.

Embodiments of the present invention will be described below with reference to the drawings. Fig. 2 is a longitudinal sectional view of the diaphragm, Fig. 3 is a longitudinal sectional view of the spring receiving plate, Fig. 4 is a longitudinal sectional view of the conical coil spring, Fig. 5 is a longitudinal sectional view of the holding plate, and Fig. 6 is a longitudinal sectional view of the conical coil spring. FIG. 4 is a plan view of FIG. 3;

The spring receiving plate 33 forms part of a spherical surface along with the bottom surface of the diaphragm 30 except for the outer periphery.
The outer cylindrical portion 33a is cut in the axial direction at a plurality of places to provide a plurality of cut pieces 37, and after the large end 34a of the conical coil spring shown in FIG. 4 is brought into contact with the spring receiving plate 33, the large end 34a Cut piece 37 in Figure 3
The conical coil spring 34 and the spring receiving plate 33 are fixed by being rolled in from the outside so that they are not separated from each other while being assembled.

A circumferential groove 35 is provided at the base of the boss 30a shown in FIG. 2, and a center hole 36 of the spring receiving plate 33 shown in FIG. 3 is press-fitted therein. For this reason, the width of the circumferential groove 35 and the diameter of the groove bottom are slightly tightened by the thickness of the spring receiving plate 33 and the diameter of the center hole, respectively, so that the center hole 36 of the spring receiving plate 33 is Circumferential groove 3
5, the diaphragm 30 and the conical coil spring 34 shown in FIG. 4 are prevented from coming off when deformed.

A convex portion 3 is provided on the presser plate 32 as a spring positioning portion for the small end portion 34b of the conical coil spring 34.
8 is fitted with the small end 34b, which is the end turn of the small end of the conical coil spring, and the diaphragm 30 is fixed by the holding plate 32, as in the conventional example, when the holding plate 32 is attached to the thrust housing 17. However, in this embodiment, bolt holes 32c and 30c are provided near the edge of the holding plate 32 and the mounting flange 30b of the diaphragm, respectively.
2c, 30c and bolt (not shown) to the flange 3 of the diaphragm of the thrust housing 17.
It is screwed into a female screw (not shown) carved at the contact position of 0b to be fixed.

FIG. 7 is a plan view of a spring receiving plate showing another embodiment of this invention, and FIG. 8 is a plan view of FIG. 7. In the figure, the spring receiving plate 33 has a cylindrical portion 33a on the edge, but without cutting the cylindrical portion 33a, the large end 34a of the conical coil spring is partially rolled in from the outside at multiple locations to form a mounting portion 37a.
A conical coil spring 34 and a spring receiving plate 33 are fixed.

When the submersible motor pump is immersed in a deep well, the sealed liquid is pressed by the external pressure through the diaphragm 30, and the pressure is balanced. The heat generated by the operation of a submersible motor pump is due to the thermal expansion of the filled liquid, the air that got mixed in when the filled liquid was put into the pump, or the air that did not escape, and the hydrogen gas generated when the air reacts with the metal parts. The pressure is increased to pressurize the diaphragm 30. At this time, even if the conical coil spring 34 is compressed into a short and irregular shape, the spring receiving plate 33 moves together with the large end of the conical coil spring 34 and moves together with the conical coil spring 34. Conversely, when the submersible motor pump is stopped, the sealed liquid and the contained gas are cooled and the internal pressure of the submersible motor pump decreases, causing the conical coil spring 34 to push the diaphragm 30 and move together. When the diaphragm 30 expands and contracts, the spring receiving plate 33 moves as the bottom of the diaphragm 30 moves because it is fixed to the boss 30a.

As explained above, since the large diameter side coil of the conical coil spring is wound and fixed from the outside with a part of the outer cylindrical part of the spring receiving plate of the expansion absorption device of the liquid-sealed submersible motor, the conical coil spring and the spring receiving plate are fixed. Since the center hole of the spring receiving plate is press-fitted into the boss of the diaphragm, the spring receiving plate and the diaphragm become one piece, so the conical coil spring and the diaphragm always operate as one, preventing abnormal deformation of the diaphragm. By eliminating this problem, we were able to extend the life of the diaphragm and improve the reliability of liquid-sealed submersible motors.

[Brief explanation of the drawing]

Figure 1 is a vertical cross-sectional view of a sealed liquid submersible motor, Figure 2
Fig. 3 is a longitudinal sectional view showing an embodiment of the present invention, Fig. 4 is a longitudinal sectional view of a conical coil spring, Fig. 5 is a longitudinal sectional view of a presser plate, and Fig. 6 is a plan view of Fig. 3. Figure, 7th
The figure is a side view of another embodiment of this invention, and FIG. 8 is a plan view of FIG. 7. 1...Frame, 2...Stator, 3...Upper frame side plate, 4...Lower frame side plate, 5...Sealing ring, 6...Upper bracket, 7...Upper radial metal, 8...Sealing ring, 9...Lower bracket, 10...Lower radial metal, 11...Rotor, 12...Motor shaft, 13...Balance ring, 14...Thrust bearing, 15...Key, 16
... Adjustment screw, 17 ... Thrust housing, 18 ... Lock nut, 19 ... Bolt, 20 ... Knock pin, 21 ... Oil seal, 22 ... Seal cover, 23 ... Sand slinger, 24 ... Coil , 25... Cable connector, 26... Cable, 27... Stator can, 28... Plug, 29... Inlet, 30...
Diaphragm, 30a... Boss, 30b... Flange, 30c... Bolt hole, 31... Hole, 32...
...Press plate, 32c...Bolt hole, 33...Spring receiving plate, 33a...Cylindrical portion, 34...Conical coil spring, 34a...Large end, 34b...End turn portion on small diameter side, 35 ... Circumferential groove, 36 ... Center hole,
37... Cut piece, 38... Convex portion.

Claims (1)

[Scope of utility model registration request] A diaphragm 30, a spring receiving plate 33,
It includes a presser plate 32 and a conical coil spring 34,
The diaphragm 30 is container-shaped and has a boss 30a at the center inside the bottom surface, the spring receiving plate 33 is dish-shaped and has a center hole 36, and the holding plate 32 has a spring positioning part 38 at the center. It is watertightly attached to the lower part 17 of the underwater motor outer frame so as to partition the inside and outside of the motor, and the center hole 36 is fitted into the boss 30a on the bottom surface of the diaphragm 30, so that the spring receiving plate 33 is accommodated in contact with the bottom of the diaphragm 30. The large end 34a of the conical coil spring 34 is in contact with the spring receiving plate 33, and the small end 34a is in contact with the spring receiving plate 33.
b is engaged with the spring positioning part 38 of the presser plate, and the conical coil spring 34 is in a compressed state.
2 is a sealed liquid submersible motor fixed to the lower part 17 of the submersible motor outer frame. motor.