JP2012137057A - Impeller for drain pump and drain pump - Google Patents

Abstract

PROBLEM TO BE SOLVED: To provide an impeller for a drain pump capable of preventing decrease in pump efficiency and the drain pump.SOLUTION: In the drain pump 1 allowing a foreign substance of a spherical solid matter having a diameter the same as the bore of a discharge opening 50 of the drain pump to pass therethrough includes: a motor 10; a rotary shaft 24 rotated by the motor 10; an impeller 42 connected to the rotary shaft 24 and including a pair of shrouds 52 and 53, one vane 54 formed between the pair of shrouds 52 and 53 and continuous to the outer circumferential edges of the shrouds 52 and 53 from the center side of the shrouds 52 and 53 at different radiuses, a suction port 58 provided at the shroud 53 and formed at the center thereof, and a discharge port 63 having an opening width formed of the pair of shrouds 52 and 53 and the vane 54, allowing a foreign substance of a predetermined particle size to pass therethrough, and smaller than the suction port 58; and a casing 41 including a pump chamber 43 housing the impeller 42.

Description

  The present invention relates to a drainage pump impeller used for water supply such as sewage and a drainage pump.

  As a drainage pump used for water supply such as dirty water, a spiral pump in which an impeller is accommodated in a spiral casing is used. The drainage pump is configured such that a suction port is provided on the lower side of the casing and a discharge port is provided on the side of the casing, and sewage sucked from the suction port is discharged from the discharge port by rotating the impeller.

  Drainage pumps used for water supply such as sewage may contain foreign matter (dirt, etc.) in the sewage, and ensure that the sewage contained in the sewage is prevented in order to prevent failure due to stagnation. 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 a high efficiency is required, an impeller called a so-called closed blade is used (for example, see Patent Document 1). . Such an impeller has a configuration in which a blade is provided between two shrouds, and there is a higher risk of foreign matter being caught in the impeller than an impeller called a semi-open blade. In addition, there is also known one in which one blade is provided in order to prevent cloth-like foreign matters from getting entangled with the blade.

JP 2002-202092 A

  The drainage pump impeller and drainage pump described above have the following problems. In the drainage pump, not only can wastewater be surely drained, but also high pump efficiency is required. However, the drainage pump impeller used in the drainage pump described above has a larger outlet flow path width of the impeller to allow foreign matters to pass through. Further, the number of blades is set to one in order to improve the passage of foreign matters. By adopting these configurations, the internal flow path becomes large, so that the flow rate is excessively decelerated, which causes a decrease in pump efficiency.

  Then, this invention aims at providing the impeller for drainage pumps and drainage pump which can prevent the fall of pump efficiency.

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

  As one aspect of the present invention, it is a drainage pump impeller through which foreign matter of a spherical solid having the same diameter as the discharge diameter of the pump can pass, and is housed in the casing of the drainage pump, and rotated by a rotating shaft. An impeller for a drainage pump that pumps fluid, a pair of shrouds, a single blade that is formed between the pair of shrouds and that continues from the center side of the shroud to the outer periphery of the shroud with different diameters, A suction port formed at the center of one of the pair of shrouds and having a diameter larger than that of the foreign matter, and a discharge port formed by the pair of shrouds and the blades and having an opening width capable of passing the foreign matter. And an outlet.

  As one aspect of the present invention, a drainage pump capable of passing a foreign object of spherical solid material having the same diameter as the discharge diameter of the pump with respect to the discharge diameter, the motor being rotated by the motor A rotating shaft connected to the rotating shaft, a pair of shrouds, a pair of shrouds formed between the pair of shrouds, and continuous with different diameters from a center side of the shroud to an outer peripheral edge of the shroud, the pair of shrouds A suction port formed at one center of the shroud and having a diameter larger than that of the foreign matter, and a discharge port formed by the pair of shrouds and the blades and having an opening width capable of passing the foreign matter. An impeller provided, and a casing having a pump chamber for housing the impeller.

  ADVANTAGE OF THE INVENTION According to this invention, it becomes possible to provide the impeller for drainage pumps and drainage pumps which can prevent the fall of pump efficiency.

Explanatory drawing which shows the structure of the drainage pump which concerns on one embodiment of this invention in a cross section.

Hereinafter, a drainage pump 1 according to an embodiment of the present invention will be described with reference to FIG.
FIG. 1 is an explanatory view showing in cross section the configuration of a drainage 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 drainage pump 1 includes a motor 10, a shaft seal device 11, and a pump 12. Such a drainage pump 1 is a so-called submersible sewage pump that is installed in a sewage tank, a sewer, or the like and transfers sewage containing foreign matter (sewage or the like).

  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 in the direction of gravity on the motor casing 21.

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

  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 rotation 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 drainage pump 1 on the installation surface. The lower member 45 is a bottom surface of the suction opening 49 provided between the plurality of leg portions 48, a discharge opening 50 provided on the side surface, a strainer 51 provided in the suction opening 49, It has. The discharge opening 50 is formed such that its diameter (discharge diameter) can pass through the particle size of foreign matter that can pass through the impeller 42. 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 drainage 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 surface of the liner ring L.

  The strainer 51 is a restricting means for restricting suction when the foreign matter contained in the sewage sucked from the suction opening 49 is larger than a predetermined particle size. Such a strainer 51 is formed so as to allow passage of foreign matters having a diameter substantially equal to or smaller than the particle size of foreign matters that can pass through the discharge port 63 of the impeller 42.

  The impeller 42 is a non-clog closed impeller, and is formed so as to allow passage of foreign matters having a predetermined particle diameter. Such an impeller 42 includes, for example, a pair of shrouds 52 and 53 and a blade 54 provided integrally between the shrouds 52 and 53. The impeller 42 has a suction port 58 for sucking fluid and a discharge port 63 for discharging the sucked fluid.

  One of the pair of shrouds 52 and 53 (hereinafter referred to as shroud 52) is formed in a disk shape. The shroud 52 has a first supported portion 57 formed with an insertion hole 56 in which the rotary shaft 24 can be inserted and a keyway is formed.

  The other of the pair of shrouds 52 and 53 (hereinafter referred to as shroud 53) is formed in an annular shape. The shroud 53 has a second supported portion 59 in which a suction port 58 is formed at the center side thereof. The shroud 52 is located above the shroud 53 with respect to the direction of gravity when the impeller 42 is attached to the rotary shaft 24.

  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 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 blade 54 pumps the sewage sucked from the suction port 58 of the shroud 53 between the shrouds 52 and 53 and the end portions, and between the end portion and the middle portion located on the outer peripheral side of the shrouds 52 and 53. An opening 63 to be moved into the chamber 43 is formed.

  The opening 63 is a discharge port 63 that discharges 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 discharge port 63 is formed such that the width (opening width) between the shrouds 52 and 53 is smaller than the diameter of the suction port 58.

  In other words, the suction port 58 is formed so that its diameter is larger than the opening width of the discharge port 63, that is, larger than the particle size of foreign matter that can pass through the impeller 42. Specifically, the suction port 58 is formed such that the diameter of the suction port 58 can pass through 110% to 160% of the opening width of the discharge port 63.

  Here, the reason why the diameter of the suction port 58 is set to 110% with respect to the opening width of the discharge port 63 is that, on the secondary side of the suction port 58, the rapid expansion of the flow path of the impeller 42, that is, the flow path This is to eliminate a region where the area suddenly increases, and if the area of the flow path does not increase rapidly, it may not be 110%.

  The reason for the 160% is that when the diameter of the suction port 58 is increased so as to be larger than 160%, the diameter of the second supported portion 59 of the liner ring L and the shroud 53, that is, the outer peripheral surface is also large. Therefore, the gap between the liner ring L and the second supported portion 59 is also large, and leakage from the gap is increased.

  The drainage pump 1 configured as described above is driven by the motor 10 when electric power is supplied via the power cable K. The motor 10 rotates the rotating shaft 24 fixed to the rotor 23 by the stator 22. As the rotor 23 rotates, the impeller 42 rotates in the pump 12.

  As shown in the water flow F in FIG. 1, the pump 12 rotates the impeller 42 so that the dirty water sucked from the suction port 58 through the strainer 51 is discharged from the discharge port 63 of the impeller 42. 41 and impeller 42 are pumped. By this pumping, the pump 12 can transfer the pumped water to the secondary side of the drainage pump 1 through the discharge opening 50.

  According to the drainage pump 1 configured in this way, in the flow path of the impeller 42 from the suction port 58 to the discharge port 63, the diameter of the suction port 58 is larger than the foreign matter that can pass through the flow path, The opening width of the discharge port 63 is the same as the particle size of the foreign matter and is smaller than the suction port 58. For this reason, the flow passage area on the secondary side of the suction port 58 does not rapidly increase with respect to the suction port 58. For this reason, it becomes possible to prevent the flow velocity of the water sucked from the suction port 58 from rapidly decreasing. That is, it is possible to prevent a decrease in pump efficiency due to a rapid decrease in flow rate.

  In addition, although the diameter of the suction port 58 is formed to be larger than the particle size of foreign matter that can be discharged by the pump 12, the strainer 51 removes foreign matter having substantially the same diameter as the particle size of foreign matter that can pass through the impeller 42. It is formed so that it can pass through. For this reason, it can prevent sucking in a foreign material larger than the particle size of the said foreign material. Thereby, in order to prevent a reduction in pump efficiency, even if the suction port 58 is made larger than the particle size of foreign matter that can be discharged by the pump 12, foreign matter larger than the particle size of foreign matter that can be discharged is sucked. It becomes possible to prevent. For this reason, it becomes possible to prevent the drainage pump 1 from being damaged or broken, and to improve the reliability.

  As described above, according to the drainage pump 1 according to the present embodiment, the diameter of the suction port 58 is made larger than the particle size of the foreign matter that the blades 42 can pass, so that the flow path of the impeller 42 is achieved. In particular, on the secondary side of the suction port 58, it is possible to prevent a rapid increase in the flow path area and to prevent a rapid decrease in the flow velocity. Thereby, it becomes possible to prevent the pump efficiency of the pump 12 from decreasing.

  Further, by allowing the strainer 51 to pass only foreign matter having a particle size substantially equal to or smaller than the particle size of the foreign matter that can be discharged from the discharge port 63 to the primary side of the suction port 58, foreign matter is blocked in the pump 12. And the reliability of the drainage pump 1 can be improved.

  The present invention is not limited to the above embodiment. For example, in the above-described example, when the particle size of the foreign matter to be sucked is larger than a predetermined particle size, the strainer 51 is provided as a restricting means for restricting the suction, and the particle size of the foreign matter that can be discharged from the discharge port 63 is approximately Although the configuration in which only foreign substances having the same or smaller particle diameter are allowed to pass is not limited to this. For example, without providing the strainer 51, the width between the leg portions 48 is substantially the same as the particle size of the foreign matter, and the foreign matter that can pass through the discharge port 63 by the leg portion 48 and the bottom surface of the water tank by being placed on the bottom surface of the water tank. It is also possible to allow a foreign substance having a diameter substantially the same as that of the particle to pass therethrough. In addition, various modifications can be made without departing from the scope of the present invention.

  DESCRIPTION OF SYMBOLS 1 ... Drain pump, 10 ... Motor, 11 ... Shaft seal device, 12 ... Pump, 13 ... Rotating shaft, 21 ... Motor casing, 22 ... Stator, 23 ... Rotor, 24 ... Rotating shaft, 25 ... Bearing, 30 ... Seal casing, 31 ... mechanical seal, 33 ... insertion hole, 34 ... oil chamber, 41 ... casing, 42 ... impeller (impeller for drainage pump), 43 ... pump chamber, 44 ... upper member, 45 ... lower member, 47 ... 1st support part, 48 ... Leg part, 49 ... Suction opening, 49a ... 2nd support part, 50 ... Discharge opening, 51 ... Strainer, 52, 53 ... Shroud, 54 ... Blade, 56 ... Insertion hole, 57 ... 1st DESCRIPTION OF SYMBOLS 1 Supported part, 58 ... Suction port, 59 ... 2nd supported part, 63 ... Discharge port, B ... Bolt, F ... Flow of sewage, K ... Power cable, L ... Liner ring.

Claims (6)

A drainage pump impeller through which foreign matter of a spherical solid having the same diameter as the pump discharge diameter can pass,
A drainage pump impeller that is housed in a drainage pump casing and rotates by a rotating shaft to pump fluid.
A pair of shrouds;
A single blade formed between the pair of shrouds and continuous with different diameters from the center side of the shroud to the outer periphery of the shroud;
A suction port formed at the center of one of the pair of shrouds and having a larger diameter than the foreign matter;
A discharge port formed by the pair of shrouds and the blades and having an opening width capable of passing the foreign matter;
An impeller for a drainage pump, comprising:   2. The drainage pump impeller according to claim 1, wherein the discharge port is formed to allow passage of a spherical solid foreign matter having a diameter equal to or less than the discharge diameter of the pump. A drainage pump capable of passing foreign matter through which spherical solid matter having the same diameter as the discharge diameter can pass,
A motor,
A rotating shaft that rotates from the motor;
One blade connected to the rotating shaft, formed between the pair of shrouds, the pair of shrouds, and continuing from the center side of the shroud to the outer peripheral edge of the shroud with different diameters, one center of the pair of shrouds And an impeller provided with a discharge port having an opening width that is formed by the pair of shrouds and the blades and is capable of passing the foreign matter, ,
A casing having a pump chamber for housing the impeller;
A drainage pump comprising:   The drainage pump according to claim 3, further comprising a restricting unit that is provided on a primary side of the suction opening and restricts suction of a foreign substance having a diameter larger than that of the foreign substance.   The drainage pump according to claim 4, wherein the restricting means is a strainer capable of passing only the foreign matter having a diameter equal to or less than the discharge diameter of the pump.   The drainage pump according to any one of claims 3 to 5, wherein the discharge port is formed to be able to pass a spherical solid foreign matter having a diameter equal to or less than the discharge diameter.

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