JP6253721B2 - Impeller and submersible pump - Google Patents

Description

  The present invention relates to an impeller for feeding sewage and the like and a submersible pump using the impeller.

  As a submersible pump used for water supply such as dirty water, a spiral pump in which an impeller is accommodated in a spiral casing is used. A submersible pump is known in which an impeller rotates to discharge dirty water sucked from a suction port provided on a lower surface of a casing from a discharge port provided on a side surface of the casing.

  Such submersible pumps used for water supply such as sewage reliably prevent filth contained in sewage in order to prevent malfunctions caused by foreign matter contained in sewage being caught in a rotating shaft or impeller. A configuration that can be discharged is required.

  For this reason, for example, a so-called semi-open blade in which a plurality of blades are provided on one shroud is used as an impeller. However, since such an impeller has poor pump efficiency, when high efficiency is required, an impeller called a so-called closed blade is used (see, for example, Patent Document 1). ).

An impeller using closed blades has a configuration in which blades are provided between two shrouds, and there is a higher risk of foreign matter being caught in the impeller than an impeller using semi-open blades.
For this reason, an impeller having a single blade between shrouds as a closed blade is also known in order to prevent foreign substances from being caught.

  As for the impeller of one blade, in order to improve pump efficiency, a technique for increasing the thickness of the blade is known. Specifically, the impeller of a single blade has a configuration in which the thickness of the blade is different at one end side, the central side, and the other end side, for example, gradually from one end side located at the center side of the impeller toward the central side. The thickness increases, and the thickness gradually decreases from the center side toward the other end side located on the outer peripheral side of the impeller.

  Such a single-blade impeller has a configuration in which only one blade is provided between the shrouds, and the thickness of the blade is different. Therefore, the mechanical balance such as arrangement and weight is poor, and vibration and noise are not generated. There is a risk of an increase.

  For this reason, when a submersible pump is arranged, a technology that improves the mechanical balance by providing a recess that hollows the inside of the blade from the shroud located on the upper side and reducing the difference in weight with other parts as much as possible It has been known.

  However, if the impeller is provided with a recess, foreign matter or the like in the sewage is accumulated in the recess, causing vibration and noise. In addition, the concave portion causes an increase in fluid resistance when the impeller rotates, and there is a problem that the shaft power of the submersible pump increases.

  Therefore, a technique is also known in which the upper surface of the shroud including the recess is covered with a lid and a discharge port for intruders in the recess is provided to prevent generation of vibration and noise (see, for example, Patent Document 2).

  A technique is also known in which an impeller is provided with a first depression and a second depression that are recessed in the axial direction so as to face each other (see, for example, Patent Document 3). On the other hand, the impeller has a configuration in which, for example, the second depression is recessed in the axial direction and upward in the direction of gravity, and therefore, an air pocket is generated in the second depression. In order to remove this air pocket, Patent Document 3 discloses a technique of providing a communication hole that communicates the first depression and the second depression.

JP 2002-202092 A JP 2006-90279 A JP 2011-137422 A

  The above-described impeller and submersible pump have the following problems. That is, in an impeller in which a single blade is provided with a concave portion and a concave portion is provided with a lid, a lid is necessary, which increases the manufacturing cost. In particular, as the outer diameter of the impeller increases, the outer diameter of the lid also increases, so that the manufacturing cost also increases. Moreover, since the cover which covers a recessed part is provided with the discharge port, there existed a problem that the stay of the foreign material in a recessed part could not be prevented.

  In addition, since the submersible pump is arranged so that the axial direction of the impeller is along the direction of gravity, the first depression is provided in the configuration in which the first depression and the second depression communicating with the impeller through the communication hole are provided. There is a risk of foreign matter accumulating on the surface. Moreover, if foreign matter accumulates in the first depression, the communication hole may be blocked by the foreign matter.

  SUMMARY OF THE INVENTION An object of the present invention is to provide an impeller and a submersible pump that can reduce manufacturing costs and can suppress vibrations and noises caused by foreign matter retention and air accumulation.

  In order to solve the problems and achieve the object, the impeller and the submersible pump of the present invention are configured as follows.

As one aspect of the present invention, an impeller that pumps fluid by rotating by a rotating shaft that is housed in a casing of a submersible pump and extends along the direction of gravity is an upper shroud that is fixed to the rotating shaft. A lower shroud provided opposite to the upper shroud and having a suction port at the center thereof, a hollow recess opening from the upper shroud or the lower shroud , and the recess and the outer surface thereof, and the upper shroud. A midway portion on the outer peripheral surface side between an end portion on the center side and an outer end portion of the shroud and the lower shroud, and is formed at the midway portion or the upper end portion in the opposing direction of the upper shroud and the lower shroud. pore portion has, integrally formed between the upper shroud and the lower shroud, a single blade which is continuous from the center side of the upper shroud and the lower shroud to the outer periphery , Comprising a.

As one aspect of the present invention, a submersible pump includes a motor, a rotating shaft connected to the motor, the impeller according to any one of claims 1 to 5, and a pump that houses the impeller. A casing.

  According to the present invention, it is possible to provide an impeller and a submersible pump that can reduce the manufacturing cost and can suppress vibrations and noise generated due to the retention of foreign matters and air accumulation.

Sectional drawing which shows the structure of the submersible pump which concerns on the 1st Embodiment of this invention. Sectional drawing which shows the structure of the submersible pump which concerns on the 2nd Embodiment of this invention. The side view which shows the structure of the impeller used for the submersible pump which concerns on the 3rd Embodiment of this invention. Sectional drawing which shows the structure of the impeller. Sectional drawing which shows the structure of the submersible pump which concerns on the 4th Embodiment of this invention.

(First embodiment)
Hereinafter, the submersible pump 1 which concerns on one embodiment of this invention is demonstrated using FIG.
FIG. 1 is an explanatory view showing, in section, the configuration of a submersible pump 1 according to an embodiment of the present invention. In FIG. 1, B represents a bolt, F represents a water flow, K represents a power cable, and L represents a liner ring.

  As shown in FIG. 1, the submersible pump 1 includes a motor 10, a shaft seal device 11, and a pump 12. Such a submersible pump 1 is a so-called submersible sewage pump that is installed in a sewage tank, a sewer, or the like and feeds sewage containing foreign matter (sewage etc.).

  The motor 10 includes a motor casing 21, a stator 22, a rotor 23, and a rotating shaft 24. The motor 10 also has a power cable K connected to an external power source or the like. The motor casing 21 is formed in a cylindrical shape in which both ends are closed, and one end surface is fixed to the shaft seal device 11 with a bolt B or the like.

The stator 22 is fixed to the inner surface of the motor casing 21. The stator 22 is formed so that the rotor 23 can be rotated by electric power supplied via the power cable K.
The rotor 23 is fixed to the rotating shaft 24 so as to be able to rotate the rotating shaft 24 following the rotation.

  The rotating shaft 24 protrudes from one end side of the motor casing 21 and is rotatably supported by the motor casing 21 via a bearing 25 such as a bearing. The rotating shaft 24 extends from the motor casing 21 in the direction of gravity.

The shaft seal device 11 includes a seal casing 30 and a mechanical seal 31.
The shaft seal device 11 liquid-tightly partitions the motor 10, the pump 12, and the rotary shaft 24.

The seal casing 30 is formed so that a mechanical seal 31 can be accommodated therein.
Such a seal casing 30 is formed in a cylindrical shape whose both ends are closed, and is provided with insertion holes 33 through which the rotary shaft 24 is inserted. Moreover, the seal casing 30 forms an oil chamber 34 in which the lubricating oil of the mechanical seal 31 can be filled.

  The mechanical seal 31 is formed so as to prevent infiltration of sewage from the pump 12 and ingress of lubricating oil into the motor 10 by sealing between the seal casing 30 and the rotary shaft 24. As described above, the shaft seal device 11 employs a so-called two-stage structure that prevents foreign matter from entering the motor 10 by providing the mechanical seal 31 in the seal casing 30 filled with lubricating oil.

  The pump 12 includes a casing 41 and an impeller 42. The casing 41 is a spiral casing that houses the impeller 42 therein, and forms a pump chamber 43 therein. The casing 41 has an upper member 44 and a lower member 45 that form a pump chamber 43 by being assembled, and is formed so as to be disassembleable with the impeller 42 fixed to the rotary shaft 24.

  In this embodiment, the upper member 44 is formed integrally with a part of the seal casing 30. The upper member 44 has a first support portion 47 that instructs the impeller 42 to be rotatable below the insertion hole 33 described above.

  The lower member 45 includes a plurality of legs 48 for installing the submersible pump 1 on the installation surface. The lower member 45 includes a suction opening 49 provided between the plurality of leg portions 48 on the bottom surface thereof, and a discharge opening 50 provided on the side surface thereof.

  In addition, the discharge opening 50 is formed so that the diameter (discharge diameter) can pass the foreign material of the particle size which can pass the impeller 42. FIG. Specifically, the diameter of the discharge opening 50 is formed to be substantially the same diameter as a foreign substance having a predetermined particle diameter that can pass through the impeller 42. Here, the foreign substance having a predetermined particle diameter that can pass through the impeller 42 is a spherical solid having the same diameter (predetermined particle diameter) as the diameter (discharge diameter) of the discharge opening 50 of the submersible pump 1.

The suction opening 49 is formed to have substantially the same diameter as a suction port 58 described later of the impeller 42.
The suction opening 49 has the 2nd support part 49a which supports the impeller 42 so that rotation is possible. The insertion hole 33, the first support portion 47, and the second support portion 49a are provided with a liner ring L that can slide with the rotary shaft 24 and the impeller 42. The first support portion 47 and the second support portion 49a are formed by the inner surfaces of these liner rings L.

  The impeller 42 is a non-clog closed impeller, and is formed so as to allow passage of a foreign substance having a predetermined particle diameter. Such an impeller 42 includes an upper shroud (first shroud) 52 disposed on the shaft seal device 11 side, a lower shroud (second shroud) 53 disposed on the suction opening 49 side, and the shrouds 52, 53. And a blade 54 provided therebetween.

  The impeller 42 has a suction port 58 for sucking fluid provided in the lower shroud 53, and a discharge port 63 formed by the upper shroud 52, the lower shroud 53, and the blades 54 for discharging the sucked fluid. . In such an impeller 42, the upper shroud 52, the lower shroud 53, and the blades 54 are integrally formed by casting or the like.

  The upper shroud 52 is formed in a disk shape. The upper shroud 52 is formed with a first supported portion 57 in which the rotation shaft 24 can be inserted and an insertion hole 56 having a key groove 56a is formed. The upper shroud 52 is located above the lower shroud 53 with respect to the direction of gravity when the impeller 42 is fixed to the rotating shaft 24.

  The lower shroud 53 is formed in an annular shape. The lower shroud 53 has a suction port 58 formed in the center thereof. Moreover, the center side of the lower shroud 53 protrudes in an annular shape, and a second supported portion 59 is formed on the outer peripheral side of the protrusion.

  The first supported portion 57 is supported by the first support portion 47 via the liner ring L so as to be rotatable and slidable. The second supported portion 59 is supported by the second support portion 49a via the liner ring L so as to be rotatable and slidable.

  One blade 54 is provided between the upper and lower shrouds 52 and 53. One end of the blade 54 is disposed on the center side of the shrouds 52 and 53, and the other end is disposed on the outer peripheral edge of the shrouds 52 and 53. The blade 54 is formed in a shape in which the diameter from the center of the shrouds 52 and 53 (the rotation center of the impeller 54) is different at each position, for example, a spiral shape or an involute shape. The detailed shape can be set as appropriate as long as the impeller 42 is capable of pumping (transferring) sewage with a predetermined pump efficiency.

  The blades 54 are thin at the end portions on the outer peripheral edges of the upper and lower shrouds 52 and 53 and gradually become thicker toward the center. The blade 54 forms a discharge port 63 that moves the sewage sucked from the suction port 58 of the lower shroud 53 into the pump chamber 43 by the shrouds 52 and 53 and between the ends thereof.

  The blade 54 is formed with a hollow inside, and a recess 55 whose lower end opens into the lower shroud 53 and a hole 55 a that communicates the outer surface with the recess 55 are formed. The wing | blade 54 has the recessed part 55 which a downward opening opens, and the inside meat | flesh is comprised.

  Specifically, the recess 55 is provided from the lower shroud 53 along the outer shape of the blade 54 to a part of the lower shroud 53 and the blade 54, and the lower shroud 53 and the blade 54 are formed along the outer shape of the blade 54. The lower shroud 53 and the blades 54 are hollow portions from which the lower ends are recessed.

  One or a plurality of hole portions 55 a are provided in the midway portion of the blade 54 in the axial direction. The hole 55a is formed so that air accumulated in the recess 55 is guided from the inside of the recess 55 to the outside so that the air pool can be removed.

The discharge port 63 is an opening for discharging the sewage sucked from the suction port 58 to the pump chamber 43.
The discharge port 63 is formed so as to be able to discharge a foreign particle having a predetermined particle size, that is, a maximum particle size of foreign particles that can pass through the impeller 42.

  The submersible pump 1 configured as described above is supplied with electric power through the power cable K, whereby the motor 10 is driven, and the rotor 23 is rotated by the stator 22, whereby the rotary shaft 24 rotates. As the rotor 23 rotates, the impeller 42 also rotates.

  As shown in the water flow F in FIG. 1, due to the rotation of the impeller 42, the sewage sucked from the suction port 58 is increased in pressure by the casing 41 and the impeller 42 and discharged from the discharge port 63.

  According to the submersible pump 1 configured as described above, by providing the blades 54 with the concave portions 55 that are hollow portions whose lower ends are open, it is possible to reduce the uneven weight balance due to the blades 54 as much as possible. This makes it possible to improve the mechanical balance such as arrangement and weight, and to prevent vibration and noise during rotation as much as possible.

  Further, the recess 55 is partly opened in the lower shroud 53, and the opening (the lower end of the recess 55) communicates with the lower portion of the casing 41, so that even if sewage enters the recess 55, it is included in the sewage. Foreign matter does not stay in the recess 55.

  Furthermore, since the rotation center of the impeller 42 is disposed substantially along the direction of gravity, and the lower shroud 53 is provided below the impeller 42, the submersible pump 1 has the recess 55 in the direction of gravity. The lower part will open. For this reason, even if sewage containing foreign matter enters the recess 55 when the submersible pump 1 is driven, the foreign matter does not fall due to gravity and stay in the recess 55 when the submersible pump 1 is stopped.

  In addition, when the submersible pump 1 is installed, the concave portion 55 is arranged along the direction of gravity, the lower portion is opened from the lower shroud 53, the ceiling surface is positioned above the concave portion 55, and the concave portion 55 is formed. The inner space 55 communicates with the outside of the blade 54 through the hole 55a. For this reason, even if an air pocket occurs in the recess 55, the air is removed from the hole 55a. As a result, it is possible to prevent the accumulation of air in the recess 55.

  In particular, when air accumulates in the recess 55, buoyancy is applied to a part of the impeller 42 due to the air, and there is a possibility that an imbalance in weight balance occurs. However, the impeller 42 can prevent an uneven weight balance by providing the hole 55a.

  Even if the impeller 42 is provided with the concave portion 55, foreign matter and air do not stay in the concave portion 55. Therefore, vibration due to an increase in weight due to accumulation of the foreign matter in the concave portion 55 or air buoyancy. Generation of noise and noise, and an increase in shaft power due to an increase in fluid resistance can be prevented, and a reduction in pump efficiency can be prevented.

  In addition, since foreign matter and air do not stay in the concave portion 55, it is not necessary to close the concave portion 55 with a separate component such as a lid, and therefore, the manufacturing process and the number of parts can be reduced. As a result, the manufacturing cost of the impeller 42 can be reduced.

  Further, since the hole 55a is disposed on the side surface of the blade 54, that is, the blade 54 along the axial direction of the impeller 42 so as to open in a direction perpendicular to the axial direction, the foreign matter is the hole. There is no deposition on 55a. For this reason, the hole 55a is not blocked by foreign matter, and the air in the recess 55 can be reliably removed.

  As described above, according to the submersible pump 1 according to the present embodiment, the blades 54 are provided with the concave portion 55 that opens downward and the hole portion 55a that communicates the concave portion 55 with the outside. Even if vibration and noise can be suppressed by improving the balance of the balance and preventing foreign matter and air from staying in the recess 55, the manufacturing cost can be reduced.

(Second Embodiment)
Next, the structure of the impeller 42A used for the submersible pump 1 according to the second embodiment of the present invention will be described with reference to FIG.

  FIG. 2 is a cross-sectional view showing a configuration of the submersible pump 1 using the impeller 42A used according to the second embodiment of the present invention. In addition, the same code | symbol is attached | subjected to the structure similar to the submersible pump 1 which concerns on 1st Embodiment mentioned above among the structures of the submersible pump 1 which concerns on 2nd Embodiment, and the detailed description is abbreviate | omitted. Moreover, since the submersible pump 1 which concerns on 2nd Embodiment is the structure equivalent to the submersible pump 1 which concerns on 1st Embodiment mentioned above except the structure of the impeller 42, the detailed description is abbreviate | omitted.

  As shown in FIG. 2, the submersible pump 1 includes a motor 10, a shaft seal device 11, and a pump 12A. Such a submersible pump 1 is a so-called submersible sewage pump that is installed in a sewage tank, a sewer, or the like and feeds sewage containing foreign matter (sewage etc.). The pump 12A includes a casing 41 and an impeller 42A.

  The impeller 42 </ b> A is a non-clog closed impeller, and is formed so as to allow passage of foreign matters having a predetermined particle diameter. The impeller 42 </ b> A includes an upper shroud 52, a lower shroud 53, and a blade 54 </ b> A provided between the shrouds 52 and 53.

  The impeller 42A includes a suction port 58 for sucking fluid provided in the lower shroud 53, and a discharge port 63 for discharging the sucked fluid, which is formed by the upper shroud 52, the lower shroud 53, and the blade 54A. ing. In such an impeller 42A, the upper shroud 52, the lower shroud 53, and the blades 54A are integrally formed by casting or the like.

  One blade 54 </ b> A is provided between the upper and lower shrouds 52 and 53. One end of the blade 54 </ b> A is disposed on the center side of the shrouds 52 and 53, and the other end is disposed on the outer peripheral edge of the shrouds 52 and 53. The blade 54A is formed in a shape in which the diameter from the center of the shrouds 52 and 53 is different at each position, for example, a spiral shape or an involute shape. The detailed shape of the impeller 42A can be set as appropriate as long as the impeller 42A is capable of pumping (transferring) sewage with a predetermined pump efficiency.

  The blades 54A are thin at the outer peripheral edge of the upper and lower shrouds 52, 53, and gradually increase in thickness toward the center.

The blade 54 </ b> A has a hollow inside, and a recess 55 whose lower end opens into the lower shroud 53, and a hole 55 b that communicates the outer surface with the recess 55.
The blade 54 </ b> A has a recess 55 that opens downward, so that the inside of the blade 54 </ b> A is thinned.

  The recess 55 is formed such that the ceiling surface is inclined upward from the center side of the impeller 42 </ b> A toward the outer peripheral side. The ceiling surface of the recess 55 is inclined upward toward the hole 55b. One or more holes 55b are provided at the upper end of the blade 54A in the axial direction, in other words, at the end of the blade 54A adjacent to the upper shroud 52. The hole 55b is formed so that the air accumulated in the recess 55 is guided from the inside of the recess 55 to the outside so that the air reservoir can be removed.

  The submersible pump 1 configured as described above is supplied with electric power through the power cable K, whereby the motor 10 is driven, and the rotor 23 is rotated by the stator 22, whereby the rotary shaft 24 rotates. As the rotor 23 rotates, the impeller 42A also rotates.

  As shown in the water flow F in FIG. 1, due to the rotation of the impeller 42 </ b> A, the sewage sucked from the suction port 58 is increased in pressure by the casing 41 and the impeller 42 </ b> A and discharged from the discharge port 63.

  According to the submersible pump 1 using the impeller 42 </ b> A configured as described above, the hole 55 b has the same effect as the submersible pump 1 using the impeller 42 described above, and the hole 55 b is an end portion above the blade 54 </ b> A. Therefore, it is possible to remove air staying at the upper end side of the recess 55. In addition, by configuring the ceiling surface of the recess 55 to be inclined upward toward the hole 55b, air staying above the recess 55 during the stop of the impeller 42A is guided to the hole 55b side. The air in the recess 55 can be effectively removed not only during the rotation of the impeller 42A but also during the stop.

(Third embodiment)
Next, the structure of the impeller 42B used for the submersible pump 1 which concerns on the 3rd Embodiment of this invention is demonstrated using FIG.3 and FIG.4.

  FIG. 3 is a side view showing the configuration of an impeller 42B used according to the third embodiment of the present invention, and FIG. 4 is a cross-sectional view showing the configuration of the impeller 43B in the IV-IV section in FIG. is there. In addition, the structure same as the impeller 42 of the submersible pump 1 which concerns on 1st Embodiment mentioned above among the structures of the impeller 42B of the submersible pump 1 which concerns on 3rd Embodiment attaches | subjects the same code | symbol, Detailed description is omitted. Moreover, since the submersible pump 1 which concerns on 3rd Embodiment is an equivalent structure except the structure of the submersible pump 1 which concerns on 1st Embodiment mentioned above, and the impeller 42, the detailed description is abbreviate | omitted.

  As shown in FIGS. 3 and 4, the impeller 42 </ b> B used in the submersible pump 1 is a non-clog closed impeller, and is formed so as to allow passage of foreign matters having a predetermined particle diameter. The impeller 42 </ b> B includes an upper shroud 52, a lower shroud 53, and a blade 54 </ b> B provided between the shrouds 52 and 53.

  The impeller 42B has a suction port 58 for sucking fluid provided in the lower shroud 53, and a discharge port 63 that is formed by the upper shroud 52, the lower shroud 53, and the blades 54B and discharges the sucked fluid. ing. In such an impeller 42B, the upper shroud 52, the lower shroud 53, and the blade 54B are integrally formed by casting or the like.

  One blade 54 </ b> B is provided between the upper and lower shrouds 52 and 53. One end of the blade 54 </ b> B is disposed on the center side of the shrouds 52 and 53, and the other end is disposed on the outer peripheral edge of the shrouds 52 and 53. The blade 54B is formed in a shape in which the diameter from the center of the shrouds 52 and 53 is different at each position, for example, a spiral shape or an involute shape. The detailed shape of the impeller 42B can be appropriately set as long as the impeller 42B is capable of pumping (transferring) sewage with a predetermined pump efficiency.

  The thickness of the blade 54B is thin at the end portions on the outer peripheral edge side of the upper and lower shrouds 52, 53, and gradually becomes thicker toward the center side.

The blade 54 </ b> B forms a hollow inside, and is formed with a recess 55 whose lower end opens into the lower shroud 53, and a hole 55 c that communicates the outer surface with the recess 55.
The blade 54 </ b> B has a concave portion 55 that opens downward, so that the inside of the blade 54 </ b> B is thinned.

  The recess 55 is formed such that the ceiling surface is inclined upward from the center side of the impeller 42B toward the outer peripheral side. The ceiling surface of the recess 55 is inclined upward toward the hole 55c. The hole 55c is formed in a slit shape in the blade 54B so as to pass between the upper and lower shrouds 52 and 53 along the axial direction of the impeller 42B (rotating shaft 24). The hole 55c is formed at a position where the inner surface of the recess 54B and the outer surface of the other end of the blade 54B (ends on the outer peripheral side of the upper and lower shrouds 52, 53) of the blade 54B are continuous.

  The width of the hole 55c is such that the air accumulated in the recess 55 and the foreign matter in the recess 55 are guided from the inside of the recess 55 to the outside by centrifugal force so that the air pool and the foreign matter can be removed. Is formed.

  According to the impeller 42B of the submersible pump 1 configured as described above, the same effect as the impeller 42 of the submersible pump 1 described above is obtained, the hole 55c is slit-shaped, and the upper and lower shrouds 52, The blades 54B are provided along the vertical direction (axial direction) so as to pass between 53. For this reason, the hole 55c can remove the air staying in the recess 55, and the foreign matter located in the recess 55 is removed from the recess 55 by the centrifugal force during the rotation of the impeller 42B. It becomes possible.

  Further, the ceiling surface of the recess 55 is inclined upward toward the hole 55c, so that air staying above the recess 55 during the stop of the impeller 42B is guided to the hole 55c side, and the impeller Even when 42B is stopped, the air in the recess 55 can be effectively removed.

  Moreover, since the hole part 55c is arrange | positioned by opening in the slit shape along the side surface of the blade | wing 54, a foreign material does not accumulate on the hole part 55a. For this reason, the hole 55c is not blocked by foreign matter, and the air in the recess 55 can be reliably removed.

(Fourth embodiment)
Next, the structure of the impeller 42C used for the submersible pump 1 which concerns on the 4th Embodiment of this invention is demonstrated using FIG.

  FIG. 5 is a cross-sectional view showing a configuration of an impeller 42C used according to the fourth embodiment of the present invention. In addition, the structure same as the impeller 42 of the submersible pump 1 which concerns on 1st Embodiment mentioned above among the structures of the impeller 42C of the submersible pump 1 which concerns on 5th Embodiment attaches | subjects the same code | symbol, Detailed description is omitted. Moreover, since the submersible pump 1 which concerns on 5th Embodiment is the structure equivalent to the submersible pump 1 which concerns on 1st Embodiment mentioned above except the structure of the impeller 42, the detailed description is abbreviate | omitted.

  As shown in FIG. 5, the submersible pump 1 includes a motor 10, a shaft seal device 11, and a pump 12C. Such a submersible pump 1 is a so-called submersible sewage pump that is installed in a sewage tank, a sewer, or the like and feeds sewage containing foreign matter (sewage etc.). The pump 12C includes a casing 41 and an impeller 42C.

  The impeller 42 </ b> C is a non-clog closed impeller, and is formed so as to allow passage of foreign matters having a predetermined particle diameter. The impeller 42C includes an upper shroud 52 disposed on the shaft seal device 11 side, a lower shroud 53 disposed on the suction opening 49 side, and a blade 54C provided between the shrouds 52 and 53. I have.

  The impeller 42C has a suction port 58 for sucking fluid provided in the lower shroud 53, and a discharge port 63 for discharging the sucked fluid, which is formed by the upper shroud 52, the lower shroud 53 and the blades 54. . In such an impeller 42C, the upper shroud 52, the lower shroud 53, and the blades 54C are integrally formed by casting or the like.

  One blade 54 </ b> C is provided between the upper and lower shrouds 52 and 53. One end of the blade 54 is disposed on the center side of the shrouds 52 and 53, and the other end is disposed on the outer peripheral edge of the shrouds 52 and 53. The blade 54 is formed in a shape in which the diameter from the center of the shrouds 52 and 53 (the rotation center of the impeller 54) is different at each position, for example, a spiral shape or an involute shape.

  The blade 54 </ b> C forms a hollow inside, and is formed with a recess 55 </ b> C whose upper end opens into the upper shroud 52, and a hole 55 d that communicates the outer surface with the recess 55 </ b> C. In addition, in the recess 55C of the blade 54C, the opening of the upper shroud 52 is closed by a hole body 55b and a lid body 60 whose lower surface is arranged substantially at the same position. It should be noted that the closing by the lid 60 does not have to be liquid-tightly closed unless foreign matter enters the recess 55c.

The recess 55C is formed such that the ceiling surface is inclined upward from the center side of the impeller 42C toward the outer peripheral side. That is, the ceiling surface of the recess 55 is inclined upward toward the hole 55d.
One or more holes 55d are provided at the upper end of the blade 54C in the axial direction, in other words, at the end of the blade 54C adjacent to the upper shroud 52 and flush with the lower surface of the lid 60. Yes.
The hole 55s is formed so that air accumulated in the recess 55C is guided from the inside of the recess 55C to the outside, and the air pool can be removed.

  According to the impeller 42 </ b> C configured as described above, the concave portion 55, which is a hollow portion in which the opening hole 60 is formed in the upper shroud 52, is provided in the blade 54, thereby reducing the weight balance deviation due to the blade 54 </ b> C as much as possible. Is possible. This makes it possible to improve the mechanical balance such as arrangement and weight, and to prevent vibration and noise during rotation as much as possible.

  Further, the blade 54C has a hole 55d, and the lower surface of the blade 54C is closed by the lid body 60, which is substantially flush with the hole 55d, so that the blade 54C stays on the upper end side of the recess 55C as in the case of 54A described above. It is possible to remove air. In addition, by adopting a configuration in which the lid body 60 of the recessed portion 55C is inclined upward toward the hole portion 55d, air staying above the recessed portion 55C while the impeller 42C is stopped is guided to the hole portion 55d side. The air in the recess 55C can be effectively removed not only during the rotation of the impeller 42C but also during the stop.

  The hole 55d is disposed on the side surface of the blade 54C, that is, on the blade 54C along the axial direction of the impeller 42C so as to open in a direction perpendicular to the axial direction, so that foreign matter is contained in the hole 55d. There is no deposit on it. For this reason, the hole 55d is not blocked by foreign matter, and the air in the recess 55C can be reliably removed.

  The present invention is not limited to the above embodiment. For example, in the above-described example, the configuration in which the upper shroud 52, the lower shroud 53, and the blades 54 are integrally manufactured by casting has been described. However, the configuration is not limited thereto. For example, the upper shroud 52 may be manufactured separately from the lower shroud 53 and the blades 54, and the upper shroud 52 and the blades 54 may be joined by welding or the like. The upper shroud 52, the lower shroud 53, and the blades 54 may be joined. May be manufactured separately and joined to each other. In other words, any configuration can be used as long as the lower end of the recess 55 of the blade 54 is continuous with the opening of the lower shroud 53.

  In the above-described example, the impeller 42C opens the recess 55C of the blade 54C with the upper shroud 52, closes it with the lid 60, and forms the hole 55d at a position flush with the lower surface of the lid 60. Although the structure to provide was demonstrated, it is not limited to this. For example, the hole may be configured to be arranged in the midway portion in the axial direction of the blade 54C, similarly to the hole 55a of the impeller 42 described above.

Further, like the hole portion 55c of the impeller 42B described above, the hole portion is slit-like in the blade 54C so as to pass between the upper and lower shrouds 52, 53 along the axial direction of the impeller 42C (rotary shaft 24). The structure formed in this may be sufficient. Moreover, you may form such a hole in the position where the outer surface of the recessed part 55C inner surface of the blade | wing 54C and the other edge part (end part of the outer peripheral side of the upper and lower shrouds 52 and 53) of the blade | wing 54C continues. By setting the width of the hole having such a configuration to a width that can guide the foreign matter in the recess 55C, the foreign matter and air in the recess 55C can be moved to the outside. For this reason, when it is set as a slit-shaped hole part, 42 C of impellers do not need to provide the cover body 60. FIG. In addition, various modifications can be made without departing from the scope of the present invention.
Hereinafter, the invention described in the scope of claims of the present application will be appended.
[1] An impeller that is housed in a casing of a submersible pump and rotates by a rotating shaft that extends along the direction of gravity to pump fluid.
An upper shroud fixed to the rotating shaft;
A lower shroud provided facing the upper shroud and having a suction port at the center thereof;
A hollow recess that is integrally formed between the upper shroud and the lower shroud and is continuous from the center side to the outer peripheral side of the upper shroud and the lower shroud, the hollow recess opening from the upper shroud or the lower shroud, and the outer surface thereof. A single blade formed with a continuous hole,
An impeller comprising:
[2] The impeller according to [1], wherein the hole is formed in an upper end portion of the blade.
[3] The impeller according to [1], wherein the hole is formed in a slit shape along an axial direction of the rotation shaft.
[4] The impeller according to [3], wherein the hole portion continues an outer surface of an outer peripheral end portion of the upper shroud and the lower shroud of the blade and an inner surface of the concave portion.
[5] The impeller according to any one of [1] to [4], wherein a ceiling surface of the concave portion is inclined upward toward the hole portion.
[6] a motor;
A rotating shaft connected to the motor;
An upper shroud fixed to the rotating shaft, a lower shroud provided opposite to the upper shroud and having a suction port at the center thereof, and integrally formed between the upper shroud and the lower shroud, the upper shroud and A blade comprising a single blade that is formed from the upper shroud or a hollow recess that opens from the lower shroud, and a hole that continues from the recess to its outer surface. Car,
A pump casing that houses the impeller;
A submersible pump characterized by comprising:
[7] The submersible pump according to [6], wherein the hole is formed in an upper end portion of the blade.
[8] The submersible pump according to [6], wherein the hole is formed in a slit shape along an axial direction of the rotating shaft.
[9] The submersible pump according to [8], wherein the hole continues the outer surface of the outer end of the upper shroud and the lower shroud of the blade and the inner surface of the recess.
[10] The submersible pump according to any one of [6] to [9], wherein a ceiling surface of the recess is inclined upward toward the hole.

  DESCRIPTION OF SYMBOLS 1 ... Submersible pump, 10 ... Motor, 11 ... Shaft seal device, 12 ... Pump, 21 ... Motor casing, 22 ... Stator, 23 ... Rotor, 24 ... Rotary shaft, 25 ... Bearing, 30 ... Seal casing, 31 ... Mechanical seal, 33 ... insertion hole, 34 ... oil chamber, 41 ... casing, 42 ... impeller, 43 ... pump chamber, 44 ... upper member, 45 ... lower member, 47 ... support part, 48 ... leg part, 49 ... suction Opening, 49a ... supporting part, 50 ... discharge opening, 52 ... upper shroud, 53 ... lower shroud, 54 ... blade, 55 ... recess, 55a ... hole, 56 ... insertion hole, 56a ... key groove, 57 ... supported part 58 ... Suction port, 59 ... Supported portion, 63 ... Discharge port, B ... Bolt, K ... Power cable, L ... Liner ring.

Claims (6)

An impeller that is housed in a casing of a submersible pump and rotates by a rotating shaft that extends along the direction of gravity, and pumps fluid,
An upper shroud fixed to the rotating shaft;
A lower shroud provided facing the upper shroud and having a suction port at the center thereof;
A hollow recess opening from the upper shroud or the lower shroud , and the recess and the outer surface thereof are continuous, and an outer peripheral surface side between the center end and the outer end of the upper shroud and the lower shroud . a middle portion, and it has the on shroud and a hole formed in a middle portion or the upper portion in the opposing direction of the lower shroud, is formed integrally between the upper shroud and the lower shroud, the upper One blade continuous from the center side to the outer peripheral side of the shroud and the lower shroud;
An impeller comprising: 2. The impeller according to claim 1, wherein the hole is formed in the upper end portion in a direction opposite to the upper shroud and the lower shroud of the blade.   2. The impeller according to claim 1, wherein the hole portion is formed in the midway portion in a facing direction of the upper shroud and the lower shroud of the blade. The said hole part continues the outer surface of the said blade | wing and the inner surface of the said outer peripheral side edge part of the said upper shroud and the said lower shroud of the said recessed part, The any one of Claim 1 thru | or 3 characterized by the above-mentioned. The impeller described in the paragraph .   The recess opens from the upper shroud;
  The impeller according to claim 2, further comprising a lid that closes the opening of the recess. A motor,
A rotating shaft connected to the motor;
An impeller according to any one of claims 1 to 5 ,
A pump casing that houses the impeller;
A submersible pump characterized by comprising: