JP2005090478A - Pump device - Google Patents

Abstract

<P>PROBLEM TO BE SOLVED: To provide a pump device with a mechanism using a rotating magnetic field generator for indirectly driving a cylindrical rotor to rotate the rotor and an impeller being held in a non-contact state in a casing, preventing a trouble resulting from contact and sliding motion between the rotor and a can and between the impeller and the casing. <P>SOLUTION: The pump device comprises the mechanism using an outer magnet 33 and an inner magnet 34, which are spaced from an outer can 31 and an inner can 32, respectively, and rotated by a driving motor 37, for indirectly driving the rotor 30 mounted on the drive side face of the impeller 20 to rotate the rotor 30 and the impeller 20 being held in non-contact in the casing 21. In the casing 21 at an outer periphery region beyond the impeller 20, a circular partition wall 23-1 is provided for partitioning the outer peripheral region into an outer periphery side and an inner periphery side. One end portion 23-1a of the partition wall 23-1 is arranged facing the inside opening of a discharge port 27 and the other end portion 23-1b of the partition wall 23-1 is arranged opposite to the discharge port 27. <P>COPYRIGHT: (C)2005,JPO&NCIPI

Description

  The present invention relates to a pump device having a non-seal structure and no bearings in the liquid. Specifically, the rotor and the impeller are driven by a rotating magnetic field generator indirectly driving a metal cylindrical rotor fixed to one side of a closed impeller. The present invention relates to a pump device provided with a mechanism for holding and rotating the impeller casing in a non-contact state.

  Various types of pump devices having a non-seal structure and a mechanism for rotating the impeller in a state where the impeller is floated in the liquid have been filed. A typical cause of failure occurring in these pump devices is that caused by contact between the rotor and the can (a partition wall separating the rotor and the rotating magnetic field generator).

  It was considered that such a failure could be prevented by the repulsive force that the rotor receives from the rotating magnetic field device. Further, it has been considered that the same failure in the vertical pump can be prevented by balancing the pressure applied to the top and bottom surfaces of the impeller and ensuring a clearance between the impeller bottom plate and the casing by a repulsive flow applied to the impeller bottom plate. Since taking such preventive measures had a certain effect, research was made on means to increase these repulsive forces, and various improvements were made, but the rotor and can were completely contactless and non-sliding. I could not do it.

  On the other hand, in order to avoid contact between the rotor and the can, ring-shaped magnets are attached to both side surfaces of the impeller, and the same-shaped ring-shaped magnet is opposed to the ring-shaped magnet on the inner surface of the casing of the pump. There is a pump device attached with a gap (see, for example, Patent Document 1).

JP-A-9-268994 (page 2-5)

  In the pump device described in Patent Document 1, contact between the rotor and the can and contact between the rotor and the can and the impeller and impeller casing by attaching ring-shaped magnets on both side surfaces of the impeller and the inner surface of the pump casing so that the same poles face each other Although the contact with the substrate could be reduced, these contacts have not been completely eliminated. For this reason, it is the actual condition that failure due to contact and sliding between the rotor and the can and between the impeller and the impeller casing cannot be eliminated.

  Therefore, the problem to be solved by the present invention is to provide a pump device in which failure due to contact and sliding between the rotor and impeller and the casing surrounding them does not occur.

  As a result of various studies as described above, it was concluded that the reason why contact and sliding between the impeller and the rotor could not be completely eliminated was not simply due to lack of repulsive force but was due to other causes. It was. For this reason, in order to balance and stabilize the behavior of the rotating parts (impeller and rotor) during operation, a pump apparatus having a structure as shown in FIG.

  In FIG. 1, the impeller 1 is a double suction system, and the suction flow from the suction port 15 to the discharge port 16 and the moving direction of the discharge flow are set as indicated by arrows (→). The outer magnet 7 and the inner magnet 8 constituting the rotating magnetic field generator that drives these rotors 9 are also arranged symmetrically. Further, the outer magnet 7 and the inner magnet 8 are driven simultaneously from the left and right via the two timing belts 12 by the timing pulleys 11 fixed to the output shafts 13a protruding from both ends of the drive motor 13, respectively. That is, it is made symmetrical with respect to the impeller 1 as a center.

  However, even with this pump device, contact and sliding between the impeller and the rotor could not be completely eliminated. Therefore, these contact and sliding are not necessarily solved even if the rotating part is bilaterally symmetric, and as a result of further research based on the judgment that there are other causes, the present invention is formed. It has come.

  In the pump device of the present invention, a metal cylindrical rotor mounted coaxially with the rotational axis on the drive side surface of a closed type impeller is indirectly driven by a rotating magnetic field generator disposed with a partition wall therebetween. And a single-sided suction / upward discharge / one-side drive side-pump device having a mechanism for rotating the impeller in a non-contact state in the casing, the outer peripheral region is located closer to the outer peripheral region than the impeller in the impeller casing. An arc-shaped partition parallel to the rotation trajectory of the impeller is provided in order to partition the outer peripheral side and the inner peripheral side, and one end of the partition is disposed facing the inner opening of the discharge port opened in the impeller casing. The other end of this is disposed at a position facing the discharge port.

  With such a configuration, the rotating liquid sucked into the impeller casing by the rotation of the impeller is diverted to the outer peripheral region and the inner peripheral region at one end of the arc-shaped partition wall, and the inside of each region is divided. After flowing, it merges again at the other end of the partition wall and flows out from the discharge port. Thereby, the hydraulic pressure in the position facing the inner opening of the discharge port of the pump casing and the hydraulic pressure in the position facing the discharge port in the pump casing can be made almost equal. For this reason, the phenomenon in which the rotating impeller is attracted toward the discharge port does not occur, and the impeller can be stably held and rotated on the shaft center. For this reason, contact and sliding between the rotor and the can and between the impeller and the impeller casing are eliminated, and failure due to these contact and sliding can be prevented.

  Here, on the suction side surface located on the opposite side to the drive side surface of the impeller, a balancing cylinder projecting to the opposite side of the rotor is provided coaxially with the rotation axis of the impeller, and the impeller casing facing this balancing cylinder body It is desirable to provide a circular concave groove in which the tip of the balance cylinder is accommodated on the inner surface. If such a balance cylinder and a concave groove are provided, a radial wedge effect is produced by the liquid present in the gap between the rotating balance cylinder and the concave groove. Without being in contact with the groove, it is rotated while being stably held in the groove.

  Therefore, the wedge effect generated in the gap between the rotor and the can and the wedge effect generated in the gap between the balance cylinder and the concave groove combine to improve the stability of the rotating impeller and the rotor. Further improve. For this reason, contact and sliding between the impeller and the impeller casing and the rotor and the can are eliminated, and a failure due to these contact and sliding can be prevented. In this case, it is desirable that the inner diameter and the outer diameter of the balancing cylinder are equal to the inner diameter and the outer diameter of the rotor.

  Further, on the inner side surface of the impeller casing facing the drive side surface and suction side surface of the impeller, a plurality of concave grooves formed radially around the rotation axis of the impeller, and a plurality of regions partitioned by these concave grooves It is desirable to provide a wedge-shaped inclined surface formed so as to form an upward gradient along the impeller rotation direction.

  By providing such a wedge-shaped inclined surface, the wedge effect generated in the gap between the rotating impeller and the casing inner surface is further increased by the liquid flowing into the gap between the impeller and the wedge-shaped inclined surface via the concave groove. Will be enhanced. Therefore, the movement of the rotating impeller in the thrust direction can be reliably avoided by the wedge effect, and contact and sliding between the impeller and the impeller casing can be prevented.

  Further, a suction hole is formed in the impeller so as to pass coaxially with the rotation axis, and the suction hole is formed in the peripheral portion of the fluid suction port that is provided coaxially with the suction hole in the impeller casing facing the suction side surface of the impeller. It is desirable to provide an auxiliary suction cylinder protruding inward. Providing such an auxiliary suction cylinder can alleviate the movement of the impeller in the thrust direction caused by the fluid sucked into the impeller when the impeller starts rotating or during rotation. For this reason, it is possible to prevent contact and sliding between the impeller at the start of rotation and the rotating impeller and the impeller casing.

  On the other hand, it is desirable to provide an inflowing liquid adjustment boss protruding into the suction hole on a part of the inner surface of the impeller casing facing the drive side surface of the impeller. Providing such an inflowing liquid adjustment boss can reduce the movement of the impeller in the thrust direction generated by the fluid sucked into the impeller when the impeller starts rotating or during the rotation, as described above. For this reason, it is possible to prevent contact and sliding between the impeller at the start of rotation and the rotating impeller and the impeller casing.

  In addition, it is desirable to provide a conical-shaped projecting portion in which the apex portion is located on the rotation axis of the impeller and the base portion of the inflowing liquid adjustment boss is smoothly spread. If such a protrusion is provided, the liquid flowing into the suction hole along the rotation axis of the impeller can be uniformly distributed and guided in the radial direction along the outer peripheral surface of the protrusion. For this reason, the movement of the impeller in the thrust direction is relieved, and the stability of the impeller at the start of rotation and during rotation is further improved.

  An extension side plate that extends the drive side surface and the suction side surface in the outer peripheral direction can be provided on the outer periphery of the drive side surface and the suction side surface of the impeller. If such an extended side plate is provided, the contact between the impeller and the impeller casing and the sliding of the impeller are also small even in a pump device in which the outer diameter of the impeller is relatively small and the area of both sides of the impeller facing the wedge-shaped inclined surface may be insufficient. Movement can be avoided.

  Furthermore, a liquid sensor that detects the presence or absence of liquid in the impeller casing and a controller that uses a liquid detection signal from the liquid sensor as a starting condition for the pump device may be provided. With such a configuration, it is possible to prevent an operation in a state where no liquid is present in the pump casing, that is, a so-called idling operation, and thus it is possible to eliminate a failure caused by the idling operation.

  According to the present invention, the following effects can be obtained.

(1) In order to divide the outer peripheral region into an outer peripheral side and an inner peripheral side in the outer peripheral region of the impeller in the impeller casing, an arc-shaped partition parallel to the rotation trajectory of the impeller is provided, and one end of the partition is provided at the impeller casing The other end of the partition wall is disposed at a position facing the discharge port, so that the liquid pressure at the position facing the discharge port and the position at the opposite position of the discharge port are set. Since the hydraulic pressure is almost equal, the rotating impeller is not attracted toward the discharge port, and the impeller can be stably held on the shaft and rotated. For this reason, the contact and sliding between the rotor and the can and between the impeller and the casing are eliminated, and a failure caused by these contact and sliding can be prevented.

(2) If a balance cylinder is provided on the suction side of the impeller, and a circular concave groove that accommodates the tip of the balance cylinder is provided on the inner surface of the impeller casing facing the balance cylinder, the balance The wedge effect generated in the gap between the cylinder and the concave groove and the wedge effect generated in the gap between the rotor and the can combine to further improve the stability of the impeller and the rotor, and the casing and the can Contact and sliding can be prevented.

(3) On the inner surface of the impeller casing, a plurality of concave grooves formed radially around the rotation axis of the impeller, and a plurality of regions partitioned by these concave grooves are respectively provided with an ascending gradient along the impeller rotation direction. If the wedge-shaped inclined surface formed as described above is provided, the wedge effect generated in the gap between the rotating impeller and the inner surface of the casing is further enhanced, so that the impeller is reliably prevented from moving in the thrust direction. And sliding between the impeller casing and the impeller casing can be prevented.

(4) Open a suction hole coaxially with the rotation axis of the impeller, and provide an auxiliary suction cylinder projecting into the suction hole at the peripheral edge of the impeller side of the fluid suction opening provided in the impeller casing. For example, since the movement of the impeller in the thrust direction generated by the fluid sucked into the impeller can be relaxed, contact and sliding between the impeller and the impeller casing can be prevented.

(5) If an inflow liquid adjustment boss protruding into the suction hole is provided on a part of the inner side surface of the impeller casing that faces the drive side surface of the impeller, the movement of the impeller in the thrust direction can be reduced as described above. Therefore, contact and sliding between the impeller and the impeller casing can be prevented.

(6) If an extension side plate that extends the driving side surface and the suction side surface in the outer peripheral direction is provided on the outer periphery of the driving side surface and the suction side surface of the impeller, the outer surface of the impeller is relatively small and both side surfaces of the impeller facing the wedge-shaped inclined surface Even in a pump device that may be insufficient in area, contact and sliding between the impeller and the impeller casing can be reliably avoided.

(7) By providing a liquid sensor that detects the presence or absence of liquid in the impeller casing and a controller that uses a liquid detection signal from the liquid sensor as a starting condition for the pump device, it is possible to prevent idling. Therefore, it is possible to eliminate failures caused by idling.

  Hereinafter, a pump device according to an embodiment of the present invention will be described with reference to the drawings. 2 is a sectional view of a pump device according to an embodiment of the present invention, FIG. 3 is a partially cutaway exploded view of the pump device shown in FIG. 2, and FIG. 4 is a sectional view taken along line X1-Y1 in FIG. is there. 5 is a diagram showing the behavior of the liquid in the casing in the pump device without a partition in the casing, and FIG. 6 shows the contact state of the impeller, rotor, casing, and can in the pump device shown in FIG. FIG. 7 is a view showing the behavior of the liquid in the casing in the pump device shown in FIG.

  The specifications of the pump device shown in FIG. 2 are as follows. The diameter of the suction pipe from the outside (the diameter of the suction opening 26) is 32 mm, and the diameter of the discharge pipe (the diameter of the discharge opening 27) is 20 mm. The material of the impeller 20 is PVC, its outer diameter is 80 mm, the diameter of the suction hole 20a is 32 mm, and the number of impeller blades is five. The rotor 30 is formed of an Al cylinder having a thickness of 3 mm, and its exposed surface is coated with Teflon (registered trademark) having a thickness of 200 μm.

  The can 38 has a double cylindrical structure with a thickness of 2 mm, and includes an inner can 31 and an outer can 32. The clearances between the inner can 31 and the outer can 32 and the rotor 30 are 2 mm. The main casing 21 has a double wall structure and a liquid passage width of 10 mm.

  The number of the outer magnets 33 and the inner magnets 34 constituting the rotating magnetic field generator is 4P, and the material thereof is a neodymium magnet. The drive motor 37 is a 3φ, 200V type, and its output is 0.4 kW. A total of eight wedge-shaped inclined surfaces B1 to B8 are formed alternately with the concave grooves 25-3 for taking in the wedge liquid, and the inclination angle θ of each wedge-shaped inclined surface B1 to B8 is 2 degrees. The pump device has a discharge amount of 50 l / min, a lift of 8 m, and a pump efficiency of 24%.

  As shown in FIGS. 2 and 3, in the pump device, the impeller casing 21 includes a partition wall 23-1 and a casing main plate 23 sandwiched between a suction side casing side plate 21-1 and a can side casing side plate 21-2. Formed and fixed by fastening these members with fastening bolts 28.

  An impeller 20 is disposed in the impeller casing 21, and an Al rotor 30 is fixed to one side (drive side surface) of the impeller 20 coaxially with the rotation axis. Therefore, if the tightening bolt 28 is loosened and removed, the impeller 20 and the rotor 30 can be easily taken out or placed in their original locations. The rotor 30 is an aluminum hollow cylindrical body that is a non-magnetic good electrical conductor, and the exposed surface thereof is coated with Teflon (registered trademark) resin.

  The impeller 20 and the rotor 30 (hereinafter referred to as “rotating portion”) are arranged so as to freely rotate in the casing 21 and the can 38 (the inner can 31 and the outer can 32). The can 38 (the inner can 31 and the outer can 32) has a double cylindrical structure made of a non-magnetic high electrical resistance material, and the bottom of the inner can 31 (the portion near the impeller 20) is closed and the other portion ( The portion near the drive motor 37 has a closed shape in which the inner can 3 and the outer can 32 are joined together.

  A plurality of sets of outer magnets 33 and inner magnets 34 are arranged on the inner side of the inner can 31 and the outer side of the outer can 32 with a gap therebetween. The outer magnet 33 and the inner magnet 34 are attached to a double cylindrical magnet holder 35 including an outer magnet yoke 33-1 and an inner magnet yoke 34-1 respectively. And the axial center part of this magnet holder 35 is connected with the output shaft (not shown) of the drive motor 37 via the holder connecting shaft 36.

  Here, with reference to FIG. 4, the arrangement | positioning state of the inner magnet 34 and the outer magnet 33 is demonstrated. As shown in FIG. 4, the opposing surfaces of the inner magnet 34 attached to the inner magnet yoke 34-1 and the outer magnet 33 attached to the outer magnet yoke 33-1 are different from each other, The magnets on the adjacent surfaces of the inner magnet 34 and the outer magnet 33 are arranged so as to be different from each other. The inner magnet 34 and the outer magnet 33 are simultaneously rotationally driven by a single drive motor 37 via a holder connecting shaft 36 fixed to the axis of the magnet holder 35.

  Thus, by rotating the inner magnet 34 and the outer magnet 33 together with the magnet holder 35, a rotating magnetic field is generated between the inner magnet 34 and the outer magnet 33, and between the inner magnet 34 and the outer magnet 33. The magnetic flux intersects with the rotor 30 to generate an induced current in the rotor 30 and to generate a rotational force and a repulsive force in the rotor 30. These rotational force and repulsive force become the rotational driving force of the impeller 20.

  Since the rotor 30 is attached only to one side (drive side surface) of the impeller 20, the center of gravity of the rotating portion including the impeller 20 and the rotor 30 is located in a portion near the rotor 30 of the impeller 20, and the impeller 20 is left and right. There is a risk of shaking. In order to prevent this, a cylindrical balance projecting to the opposite side of the rotor 30 on the impeller side plate 20-1 constituting the suction side surface located on the opposite side of the drive surface of the impeller 20 (the surface on which the rotor 30 is attached). A cylinder 20-3 is provided. The balance cylinder 20-3 is provided coaxially with the rotation axis of the impeller 20, and the balance cylinder 20-3 is formed on the inner surface of the suction side casing side plate 21-1 facing the balance cylinder 20-3. A circular concave groove 21a is formed in which the tip side is accommodated.

  By providing such a balancing cylinder 20-3 and the concave groove 21a, the liquid present in the gap between the rotating balancing cylinder 20-3 and the concave groove 21a causes a radial wedge effect. The balance cylinder 20-3 rotates in a state of being stably held in the concave groove 21a without contacting the inner wall of the concave groove 21a.

  Therefore, the wedge effect generated in the gap between the rotor 30 and the can 38 and the wedge effect generated in the gap 30 between the balance cylinder 20-3 and the concave groove 21a and the gap 30 are combined to rotate the impeller during rotation. 20 and the stability of the rotor 30 are further improved. For this reason, the contact and sliding between the impeller 20 and the impeller casing 21 and the rotor 30 and the can 38 are eliminated, and failure due to these contact and sliding can be prevented. In this embodiment, when the inner diameter and the outer diameter of the balancing cylinder 20-3 are equal to the inner diameter and the outer diameter of the rotor 30, the stability of the impeller 20 and the rotor 30 is excellent.

  Further, as shown in FIG. 3 and FIG. 7 to be described later, a suction hole 20a is formed in the impeller 20 so as to pass coaxially with the rotation axis, and suction is performed on the inner surface of the casing side plate 21-1 facing the suction side surface of the impeller 20. An auxiliary suction cylinder 21-1-1 that protrudes into the suction hole 20a is provided at the peripheral edge of the fluid suction port 26 that is opened coaxially with the hole 20a.

  By providing the auxiliary suction cylinder 21-1-1, the movement of the impeller 20 in the thrust direction, which is generated by the fluid sucked into the impeller 20 at the start or during the rotation of the impeller 20, can be reduced. For this reason, it is possible to prevent contact and sliding between the impeller 20 and the impeller casing 21 when the impeller 20 starts to rotate.

  Further, an inflow liquid adjusting boss 31-1 protruding into the suction hole 20a is provided at a central portion of the inner surface of the casing side plate 21 facing the drive side surface of the impeller 20 (bottom of the inner can 31). By providing such an inflowing liquid adjustment boss 31-1, the movement in the thrust direction of the impeller 20 generated by the fluid sucked into the impeller 20 at the start of the rotation of the impeller 20 or during the rotation is reduced as described above. can do. For this reason, it is possible to prevent contact and sliding between the impeller 20 and the impeller casing 21 when the impeller 20 starts to rotate.

  Further, a conical protrusion 31-1a having a vertex portion located on the rotational axis of the impeller 20 and a smoothly extending base portion is provided on the front end surface of the influent adjustment boss 31-1. By providing such a protrusion 31-1a, the liquid flowing into the suction hole 20a along the rotation axis of the impeller 20 is uniformly distributed in the radial direction along the outer peripheral surface of the protrusion 31-1a. It becomes possible to do. For this reason, the movement of the impeller 20 in the thrust direction is alleviated, and the stability of the impeller 20 at the start of rotation and during rotation can be further improved.

Here, FIG. 5 is a diagram showing the relationship between the pump impeller 20 and the impeller casing 23 when the discharge port 27 is located upward in the conventional pump device. In FIG. 5, when the center point of the impeller 20 is φ ₁ , the impeller 20 rotates, and when the liquid discharge from the projecting port 27 starts, the hydraulic pressure P _{1 at the} position facing the discharge port 27 in the impeller casing 23 is It becomes lower than the pressure P ₂ at the symmetrical position across the suction port 26.

At this time, the impeller 20 which is in a non-contact state in the impeller casing 23 is pushed upward by the pressure difference between the hydraulic pressure P ₁ and the pressure P ₂ as shown in FIG. When impinging on the outer can 32, the impeller 20 and the rotor 30 rotate while being tilted. At this time, the rotor 30 is in contact with the inner can 31 and the outer can 32 at Q ₁ and Q ₂ , and the impeller 20, the suction side casing side plate 21-1 and the can side casing side plate 21-2 are Q ₃ , Q Contact at ₄ part.

  If the sliding caused by such contact is simply due to insufficient repulsive force, the rotor 30, the inner can 31 and the outer can 32 should slide entirely. However, considering that such contact and sliding occur only partially, it cannot be said that the repulsive force is insufficient.

  In order to solve such contact and sliding phenomenon, the pump device of this embodiment employs a structure as shown in FIG. As shown in FIG. 7, an arc-shaped partition wall 23-1 that is parallel to the rotation trajectory of the impeller 20 is provided in the outer peripheral region of the impeller 20 in the casing 21 in order to partition the outer peripheral region into the outer peripheral side and the inner peripheral side. The one end 23-1a of the partition wall 23-1 is disposed facing the inner opening of the discharge port 27 provided at the upper end of the casing 21, and the other end 23-1b of the partition wall 23-1 is connected to the discharge port 27. It is arranged at the opposite position.

  Thus, an arc-shaped double wall is formed by the partition wall 23-1 and the outer wall 23-2, and an arc-shaped closing wall 23-5 is arranged at a position facing these double walls. And between the one end part 23-1a and the other end part 23-1b of the partition 23-1, and the closing wall 23-5, the discharge holes 23-3 and 23-4 respectively connected with the outer peripheral area | region of the impeller 20 are provided. Established and its size is almost the same. The liquid flow that has passed through the lower discharge hole 23-4 flows through the discharge liquid passage 24 between the partition wall 23-1 and the outer wall 23-2, and passes through the upper discharge hole 23-3 at a position facing the discharge port 27. It merges with the liquid flow that has passed.

As described above, the arc-shaped partition wall 23-1 is provided in the outer peripheral region of the impeller 20 in the casing 21, the one end portion 23-1 a is arranged facing the inner opening of the discharge port 27, and the other end portion 23- When 1b is disposed at a position facing the discharge port 27, the hydraulic pressure P _{1 at the} discharge hole 23-3 is approximately equal to the hydraulic pressure P _{2 at the} discharge hole 23-4. Therefore, the impeller 20 rotates at a normal position without deviating from the rotation axis, and the rotation portion does not incline, and the rotor 20 and the inner can which are generated in the conventional pump device shown in FIGS. 31, contact with the outer can 32, sliding phenomenon, contact with the casing 21 due to the inclination of the impeller 20, and sliding phenomenon could be eliminated.

  On the other hand, in the pump device of the present embodiment, a thrust force (force in the direction of the rotational axis = force in the axial direction of the holder connecting shaft 36) is generated in the impeller 20, and this magnitude depends on the pump head and the discharge amount. Change. Due to such a thrust force, the impeller 20 tilts to the left and right, so that it slides with the casing 21 as it is.

  In order to prevent this, in the pump device of this embodiment, as shown in FIG. 2, the wedge side portions 25-1 and 25 are respectively provided on the casing side plates 21-1 and 21-2 facing the impeller side plates 20-1 and 20-2. -2 is provided. As shown in FIG. 9, which will be described later, the wedge surface portions 25-1 and 25-2 include eight concave grooves 25-3 formed radially around the rotation axis of the impeller 20, and these concave grooves 25-. The wedge-shaped inclined surfaces B <b> 1 to B <b> 8 are formed in the eight regions partitioned by 3 so as to form an upward gradient along the impeller rotation direction R.

  If the wedge surface portions 25-1 and 25-2 are provided, when the impeller 20 approaches the casing side plates 21-1 and 21-2 by the thrust force, the impeller 20 and the wedge surface portions 25-1, Since the wedge effect is generated by the liquid flowing into the gap with 25-2, contact between the two can be prevented.

  Here, the wedge effect will be described in detail with reference to FIGS. FIG. 8 is a partial cross-sectional view showing a pump device according to another embodiment, FIG. 9 is a view taken in the direction of arrows X2-Y2 in FIG. 8, and FIG. 10 shows an impeller side plate 20-1 (20-2). It is a figure which shows the relationship with the wedge surface part 25-1 (25-2).

As shown in FIG. 9, the wedge surface portion 25-2 of the casing side plate 21-2 is partitioned by a plurality of concave grooves 25-3 into a plurality of wedge-shaped inclined surfaces B1 to B8. In FIG. 9, an arcuate arrow 39 with a plurality of branch lines represents the upward gradient of the wedge-shaped inclined surfaces B1 to B8, R represents the rotational direction of the impeller 20, and W entered the wedge-shaped inclined surfaces B1 to B8. This represents the flow direction of the liquid. In FIG. 10, θ represents the inclination angle of the wedge-shaped inclined surfaces B1 to B8, and g ₁ and g ₂ represent the wedge surface portion 25-1 (25-2) of the casing side plate 21-2 and the impeller side plate 20-1 (20− 2).

The repulsive force FA generated by the wedge surface portion 25-1 (25-2) is roughly expressed as follows. If the viscosity of the liquid and the inflow speed of the liquid into the wedge surface portion 25-1 (25-2) (in this embodiment, it is assumed to be proportional to the rotational speed of the impeller 20) are constant,
FA∝ (b ² × L × n) / g ₁ ²
(B: width of wedge-shaped inclined surface, L: length of wedge-shaped inclined surface, n: number of wedge-shaped inclined surfaces)
It can be expressed as.

Here, g ₂ is a gap on the inlet side to the wedge-shaped inclined surfaces B1 to B8, g ₁ is a gap on the outflow side, and a value of g ₂ / g ₁ = 2 to 4 is normal. , L and θ are determined. From the above, when the outer diameter of the impeller 20 is small, the area (b × L) that can be opposed to the wedge surface portion 25-1 (25-2) is narrowed and the wedge effect is reduced. There is a tendency to greatly decrease as the value becomes narrower.

  As a countermeasure against the reduction of the wedge effect, when the outer diameter of the impeller 20 is small, the blades of the impeller 20 are left as they are, and only the side plates of the impeller 20 are enlarged, and the facing casing side plates 21-1, 21-2 are opposed. It is desirable to expand the wedge surface portions 25-1 and 25-2. That is, as shown in FIG. 8, while providing the extension part 20-1-1 and 20-2-1 in the outer periphery of the impeller side board 20-1 and 20-2 which comprises the impeller 20, the casing side board 21 facing this is provided. The necessary wedge effect can be secured by enlarging the wedge surface portions 25-1 and 25-2 of -1 and 21-2.

  In the pump device of this embodiment, only the rotor 30 has to use metal in the liquid. In order to prevent corrosion (electric corrosion), the exposed surface (contact surface with the liquid) needs to be sufficiently coated or lined with resin or the like, but the rotor 30 with coating or the like is applied to the impeller 20. When attaching, it is dangerous to attach directly with screws, screws, etc., and should be attached indirectly.

  That is, as shown in FIG. 11, it is desirable that the rotor 30 is not directly attached to the impeller 20 with screws 30-2 but attached via an auxiliary mounting plate 30-1 made of resin. This is because, when a screw hole is made in the rotor 30, it is difficult to completely coat the inside of the screw hole, and if there is a poorly coated part inside the screw hole, this causes electric corrosion. .

  Between the start-up and full-speed operation of the pump device of this embodiment, the rotor 30 receives a rotational force, a repulsive force, and a wedge effect received from the rotating magnetic field device (the outer magnet 33, the inner magnet 34, and the magnet holder 35). FIG. 12 shows the characteristics of the repulsive force caused by the liquid flow between the rotor 38 and the rotor 30. In the graph shown in FIG. 12, the speed (slip S) of the rotor 30 is taken on the horizontal axis, the rotational force T received by the rotor 30 on the vertical axis, the repulsive force Fm received by the rotor 30 from the magnetic field, and the repulsive force FA caused by the wedge effect. The characteristics are shown when taken.

  In FIG. 12, a curve C1 shows a rotational force T, a curve C2 shows a repulsive force Fm caused by a magnetic field, and a curve C3 shows a repulsive force FA caused by a wedge effect. Here, the slip S is S = (no−n) / no when the rotational speed no of the outer magnet 33 and the inner magnet 34 and the rotational speed n of the rotor 30 are set. The rotational force T received by the rotor 30 by the rotating magnetic field approximates the rotational force-speed characteristic of a general-purpose drive motor having an extremely large gap, and thus is approximately C1.

  The repulsive force Fm received by the rotor 30 from the rotating magnetic field is a repulsive force when S · Rm> 1, and is attracted when S · Rm <1. Here, Rm is a numerical value determined by a magnetic gap between the magnets 33 and 34 and the rotor 30, a thickness of the rotor 30, a material, and the like, and is called a magnetic Reynolds number.

  As can be seen from the graph shown in FIG. 12, the point at which S is maximized, that is, S = 1 at the time of activation, the repulsive force is maximum at this time. That is, since the rotor 30 receives the maximum repulsive force at the time of activation, the rotor 30 first floats and then starts to rotate. Thereby, the sliding between the rotor 30 and the can 38 does not occur at the time of starting, which is convenient.

  On the other hand, when the rotational speed of the rotor 30 increases, that is, when the rotational speed of the impeller 20 increases, the repulsive force becomes 0 at S = 0. However, the repulsive force generated by the wedge effect generated between the can 38 and the rotor 30 increases proportionally as the rotational speed of the rotor 30 increases as long as liquid exists. Assuming that the slip S1 is obtained when the rotor 30, that is, the impeller 20 is rotated normally, the repulsive force received by the rotor 30 is FmS1 + FAS1, and the rotor 30 is lifted and stabilized. However, if no liquid is present, FA = 0, the rotational speed of the rotor 30 further increases, Fm becomes extremely small, and the repulsive force is almost eliminated.

  This indicates that the repulsive force becomes extremely small when no liquid is present, and the rotor 30 and the can 38 slide. Therefore, it is necessary to take measures to prevent idling in the pump device, and at least when the casing 21 is empty, it is necessary to prevent the drive motor 37 from starting.

  Therefore, in the pump device of this embodiment, as shown in FIG. 2 described above, a liquid sensor 29 for detecting the presence or absence of liquid is attached in the vicinity of the discharge port 27, and a liquid detection signal from the liquid sensor 29 is used to start the pump device. As a condition. That is, when there is no liquid detection signal from the liquid sensor 29, the drive motor 37 is not activated. This can prevent idling of the pump device. As a means for preventing the idling of the pump device, there is a method of filling the pump casing with liquid even when the pump is stopped.

  In the pump device according to the present embodiment, the rotating part (the rotor 30 and the impeller 20) and the peripheral wall (the casing 21 and the can 38) are not only during the start, stop, and operation, but also in the fully opened and fully closed state of the discharge valve. No sliding trace was observed. Inspecting the rotating part with inspection coating and operating, then inspecting the presence or absence of sliding according to the presence or absence of peeling of the inspection coating, there is no problem even in testing with fine slurry or limestone liquid There wasn't. In addition, it was confirmed that a reactivation can always be performed by attaching a check valve (not shown) to the suction pipe (not shown) connected to the suction port 26.

  As described above, the pump device according to the present embodiment has a non-seal structure, does not have a bearing in the liquid, and the rotating portion (the rotor 30 and the impeller 20) floats without contacting the peripheral wall (the casing 21 and the can 38). Because it can be operated in a very stable state, there is no contamination caused by sliding. In addition, since all the portions that come into contact with the liquid can be made of a synthetic resin material, a resin coating material, a ceramic material, or the like, it is not necessary to use a metal material for the liquid contact surface. This indicates that elution of metal ions into the liquid fed by the pump device can be eliminated. In addition, the absence of a sliding part during operation realizes a drastic reduction in failure, prolongation of service life, and can be maintenance-free.

  The pump device of the present invention can be used for pure liquids and corrosive liquids, and can be widely used in various technical fields for pumping and transferring various liquids such as a fine slurry mixed liquid.

It is a longitudinal cross-sectional view which shows the pump apparatus which is trial manufacture. It is sectional drawing of the pump apparatus which is embodiment of this invention. FIG. 3 is a partially cutaway exploded view of the pump device shown in FIG. 2. It is the X1-Y1 sectional view taken on the line in FIG. It is a figure which shows the behavior of the liquid in a casing in the pump apparatus without a partition in a casing. It is a figure which shows the contact state of the impeller in the pump apparatus shown in FIG. 5, a rotor, a casing, and a can. It is a figure which shows the behavior of the liquid in the casing in the pump apparatus shown in FIG. It is a fragmentary sectional view of the pump device which is other embodiments. FIG. 9 is a view taken along line X2-Y2 in FIG. It is a figure which shows the positional relationship of the wedge surface and impeller which comprise the pump apparatus shown in FIG. It is sectional drawing which shows other embodiment regarding the attachment structure of a rotor. FIG. 3 is an operational characteristic diagram of a rotor constituting the pump device shown in FIG. 2.

Explanation of symbols

DESCRIPTION OF SYMBOLS 1 Impeller 2 Impeller and rotor connecting shaft 3 Impeller main casing 4 Impeller casing inner plate 5 Can 6 Inner / outer magnet holder 7 Outer magnet 8 Inner magnet 9 Rotor 10 Pump casing 11 Timing pulley 12 Timing belt 13 Drive motor 13a Output shaft 14 Tightening bolt 15 Suction port 16 Discharge port 20 Impeller 20a Suction hole 20-1, 20-2 Impeller side plate 20-1-1, 20-2-1 Extension side plate 20-3 Balancing cylinder 21 Impeller casing 21a, 25-3 Concave groove 21 -1,21-2 Casing side plate 21-1-1 Auxiliary suction cylinder 22 Drive unit casing body 23 Casing main plate 23-1 Bulkhead 23-2 Outer wall 23-1a One end 23-1b Other end 23-3 Upper discharge hole 23 -4 Lower discharge hole 23-5 Closed wall 24 Discharge liquid passage Paths 25-1, 25-2 Wedge surface portion 26 Suction port 27 Discharge port 28 Tightening bolt 29 Liquid detection sensor 30 Rotor 30-1 Auxiliary plate for mounting 30-2 Screw 31 Inner can 31-1 Inflow liquid adjustment boss 31-1a Projection Part 32 Outer can 33 Outer magnet 33-1 Outer magnet yoke 34 Inner magnet 34-1 Inner magnet yoke 35 Magnet holder 36 Holder connecting shaft 37 Drive motor 38 Can 39 Arrow line P ₁ , P ₂ hydraulic pressure φ ₁ impeller center Q ₁ rotor and the can of the contact point Q ₂ rotor and the can of the contact point Q ₃ impeller and the contact point Q ₄ impeller and the inflow direction θ wedge in the rotational direction W liquid contact point B1~B8 wedge inclined surface R impeller casing of the casing inclination angle g _1, g ₂ wedge inclined surface and the gap b wedge inclined surface width L wedge-shaped inclined surface length S slip T rotational force of the impeller side plates of the inclined surface Attractive force Fm repulsive force FA wedge effect due to repulsion C1 T-S characteristic curve C2 Fm-S characteristic curve C3 FA-S characteristic curve S1 slip during normal operation

Claims (7)

A metal cylindrical rotor fixed coaxially with the rotation axis of the closed impeller is indirectly driven by a rotating magnetic field generator arranged with a partition wall therebetween, so that the rotor and impeller are not moved in the casing. In the horizontal type pump device with single suction, upper discharge, single side drive, equipped with a mechanism to rotate while holding it in contact,
An arc-shaped partition parallel to the rotation trajectory of the impeller is provided in the outer peripheral region of the impeller casing in the outer peripheral region to divide the outer peripheral region into an outer peripheral side and an inner peripheral side, and one end portion of the partition is A pump device, wherein the pump device is disposed facing an inner opening of a discharge port provided in a part of an impeller casing, and the other end of the partition wall is disposed at a position facing the discharge port.   On the suction side surface located on the opposite side of the drive side surface of the impeller, a balancing cylinder projecting to the opposite side of the rotor is provided coaxially with the rotation axis of the impeller, and the impeller faces the balancing cylinder. The pump device according to claim 1, wherein a circular concave groove in which the tip end side of the balance cylinder is accommodated is provided on an inner surface of the casing.   A plurality of concave grooves formed radially around the rotation axis of the impeller and a plurality of regions partitioned by the concave grooves on the inner side surface of the impeller casing facing the driving side surface and the suction side surface of the impeller, respectively. The pump device according to claim 1 or 2, further comprising a wedge-shaped inclined surface formed so as to form an upward gradient along the rotation direction of the impeller.   The impeller has a suction hole that extends coaxially with the rotational axis thereof, and the impeller side peripheral edge of the fluid suction port that is provided coaxially with the suction hole in the impeller casing facing the suction side surface of the impeller The pump device according to any one of claims 1 to 3, wherein an auxiliary suction cylinder protruding into the liquid inflow port is provided at a portion.   The pump device according to any one of claims 1 to 4, wherein an inflow adjusting boss protruding into the suction hole is provided on a part of the inner side surface of the impeller casing facing the driving side surface of the impeller.   The pump device according to any one of claims 1 to 5, wherein an extended side plate that extends the drive side surface and the suction side surface in the outer peripheral direction is provided on the outer periphery of the drive side surface and the suction side surface of the impeller.   The pump according to any one of claims 1 to 6, further comprising: a liquid sensor that detects the presence or absence of liquid in the impeller casing; and a controller that uses a liquid detection signal from the liquid sensor as a starting condition of the pump device. apparatus.

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